Updated on 2026/08/07

写真a

 
nagai takehiro
 
Organization
School of Engineering Associate Professor
Title
Associate Professor
Homepage
https://sites.google.com/view/tokyotech-ice-nagailab/
External link

Degree

  • Doctor of Engineering ( Tokyo Institute of Technology )

Research Interests

  • Material perception

  • Affective Engineering

  • Visual information processing

  • Color vision

  • Psychophysics

Research Areas

  • Humanities & Social Sciences / Cognitive science

  • Humanities & Social Sciences / Experimental psychology

  • Informatics / Kansei informatics

Research History

  • Institute of Science Tokyo   Department of Information and Communications Engineering   Associate Professor

    2024.10

    　 More details

  • Tokyo Institute of Technology   Associate Professor

    2018.4 - 2024.9

    　 More details

  • Yamagata University   Associate Professor

    2013.4 - 2018.3

    　 More details

Professional Memberships

▼display all

Committee Memberships

  • The Color Science Association of Japan   Vice Chair of the Journal Editorial Committee  

    2026.6   

    　 More details

    Committee type：Academic society

    researchmap

  • Vision Society of Japan   organizing member  

    2025.9   

    　 More details

    Committee type：Academic society

    researchmap

  • The Color Science Association of Japan   Board Member  

    2025.6   

    　 More details

    Committee type：Academic society

    researchmap

  • 日本色彩学会   視覚情報基礎研究会 幹事  

    2023.4   

    　 More details

    Committee type：Academic society

    researchmap

  • Japan Lighting Manufacturers Association   Member, CIE Division 1 National Subcommittee  

    2022.4   

    　 More details

    Committee type：Academic society

    researchmap

  • 日本照明学会   質感と照明に関する研究調査委員会 幹事  

    2020.4 - 2023.3   

    　 More details

    Committee type：Academic society

    researchmap

  • 日本色彩学会   関東支部 代議員  

    2020.4 - 2022.3   

    　 More details

    Committee type：Academic society

    researchmap

  •   映像情報メディア学会 ヒューマンインフォメーション研究委員会 委員長  

    2019.4 - 2023.3   

    　 More details

  • 日本視覚学会 若手の会   代表  

    2018.4 - 2020.3   

    　 More details

    Committee type：Academic society

    researchmap

  • 日本視覚学会 若手の会   運営メンバー  

    2016.4 - 2018.3   

    　 More details

    Committee type：Academic society

    researchmap

  • 日本色彩学会   日本色彩学会誌 編集委員  

    2014.6 - 2018.5   

    　 More details

    Committee type：Academic society

    researchmap

  • 映像情報メディア学会 ヒューマンインフォメーション研究委員会   幹事  

    2013.4 - 2019.3   

    　 More details

    Committee type：Academic society

    researchmap

  • The Vision Science & Technology Consortium   Secretary  

    2012.4   

    　 More details

    Committee type：Academic society

    researchmap

▼display all

Papers

  • The perception of realism is correlated with physical gamuts Reviewed International journal

    Killian Duay, Takehiro Nagai

    Scientific Reports   2026.8

    　More details

    Authorship：Last author   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    DOI： 10.1038/s41598-026-65139-7

    researchmap

  • Effects of “temporal preparation” on neural processing of physical and affective material attributes Reviewed International journal

    Kenta Nakajima, Takehiro Nagai

    Journal of Vision   26 ( 7 )   12 - 12   2026.7

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Association for Research in Vision and Ophthalmology (ARVO)  

    DOI： 10.1167/jov.26.7.12

    researchmap

  • Comparison of simple reaction times across colour and luminance conditions under an abrupt decrease in background luminance Reviewed International journal

    Minwoo Son, Takehiro Nagai

    Lighting Research & Technology   14771535261442940 - 14771535261442940   2026.5

    　More details

    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：SAGE Publications  

    In daily life, we frequently encounter an abrupt decrease in background luminance. Although most real-world objects exhibit compound colours containing both luminance and chromaticity information, visual performance for such stimuli remains insufficiently explored. Can chromaticity compensate for decreased luminance sensitivity and support visual performance under such conditions? This study quantified reaction times (RTs) to luminance (achromatic), chromaticity (isoluminant) and compound colour (combined luminance and chromaticity) stimuli following an abrupt decrease in background luminance, to clarify whether chromatic information is necessary for shortening RTs. The main findings are as follows. First, the effect of the abrupt luminance decrease was similar across all colours. This was suggested by a modified version of Piéron’s Law incorporating the sensitivity efficiency parameter, showing no statistically significant difference between luminance and chromaticity. Second, luminance consistently produced shorter RTs both immediately after the decrease and some time thereafter, suggesting that adding chromaticity does not necessarily confer an advantage. Interestingly, RTs for compound colours, though containing both luminance and chromaticity components, resembled either luminance or chromaticity alone, with high contrast producing luminance-like RTs and low contrast producing chromaticity-like RTs, indicating a dynamic, contrast-dependent shift in processing pathways.

    DOI： 10.1177/14771535261442940

    researchmap

    Other Link： https://journals.sagepub.com/doi/full-xml/10.1177/14771535261442940

  • Optimal colors can predict luminosity thresholds in natural scenes Reviewed International journal

    Killian Duay, Takehiro Nagai

    PLOS One   21 ( 3 )   e0343984   2026.3

    　More details

    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Public Library of Science (PLoS)  

    Luminosity thresholds define the luminance boundary at which a surface color shifts in appearance from being perceived as an illuminated surface to appearing self-luminous. Previous research suggests that the human visual system infers these thresholds based on internal references of physically realizable surface colors under a given illumination, referred to as the physical gamut. A surface is perceived as self-luminous when its luminance exceeds the upper limit of this empirically internalized gamut. However, the precise structure and boundaries of these gamuts remain uncertain. Optimal colors, which represent theoretical surface reflectances under specific illuminants, have been shown to provide an effective model for visualizing and computing the physical gamuts. In prior studies, optimal colors have successfully predicted luminosity thresholds; however, these findings were limited to highly simplified, abstract stimuli. Whether this framework generalizes to more naturalistic viewing conditions has remained an open question. In the present study, we demonstrate that the theory of an internal reference in the form of an empirically constructed physical gamut, visualized through optimal colors, remains valid under more natural conditions. Our results confirm that optimal colors can still accurately predict luminosity thresholds in such settings. Moreover, our findings suggest that the luminosity thresholds encompass both self-luminosity and naturalness concepts. Consequently, this may imply that the notion of physical gamut could encompass both concepts as well and could be defined as “all physically possible colors in a scene for an object that does not emit light.” These insights have profound potential implications for applied fields (e.g., XR or projection mapping). For example, they provide a theoretical framework that specifies the luminance and color boundaries virtual objects should not exceed to remain realistically integrated into AR/MR scenes. In fundamental science, these findings can improve our understanding of the perception of naturalness in images.

    DOI： 10.1371/journal.pone.0343984

    researchmap

  • Time course of color appearance under the abrupt decrease in background luminance Reviewed International journal

    Minwoo Son, Takehiro Nagai

    Color Research & Application   51 ( 1 )   e70042 - e70042   2026.1

    　More details

    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

    ABSTRACT

    In daily life, we often encounter an abrupt decrease in background luminance—such as stage lighting changes or display scene transitions. While many studies have explored discrimination sensitivity under such conditions, especially considering adaptation, the effects on color appearance remain less understood. The time course of color appearance across a range from low to high contrast, the abrupt decrease in background luminance, remains insufficiently understood. This study examined the time course of hue and saturation judgments for the chromatic stimuli of 16 hue angles each with four contrast levels following the abrupt decrease in background luminance from 100 to 1 cd/m 2 . Color stimuli were shown at various stimulus onset asynchronies (SOAs). Results showed that hue judgment remained stable regardless of stimulus contrast. Furthermore, additional analyses revealed that hue judgment did not vary substantially across stimulus contrasts. This means that hue judgment is unaffected by the abrupt decrease in background luminance. In contrast, saturation judgment was significantly influenced: it appeared lower right after the luminance decrease, then gradually increased over time, especially for stimuli with higher contrasts. In summary, the abrupt decrease in background luminance has a substantial impact on saturation.

    DOI： 10.1002/col.70042

    researchmap

  • Impact of field of view on color constancy in virtual reality Reviewed International journal

    Killian Duay, Takehiro Nagai

    Journal of the Optical Society of America A   42 ( 5 )   B199 - B213   2025.5

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1364/JOSAA.544170

    researchmap

  • Attention plays a greater role in judging large color differences than small ones Reviewed International journal

    Kashi Li, Takehiro Nagai

    Journal of the Optical Society of America A   42 ( 5 )   B353 - B364   2025.5

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1364/JOSAA.543658

    researchmap

  • VR HMD color calibration and accurate control of emitted light using Three.js Reviewed International journal

    Killian Duay, Yoko Mizokami, Takehiro Nagai

    Journal of Vision   25 ( 2 )   4 - 4   2025.2

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Association for Research in Vision and Ophthalmology (ARVO)  

    DOI： 10.1167/jov.25.2.4

    researchmap

  • Top-down effects on translucency perception in relation to shape cues Reviewed International coauthorship International journal

    Takehiro Nagai, Hiroaki Kiyokawa, Juno Kim

    PLOS ONE   20 ( 2 )   e0314439   2024.11

    　More details

    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1101/2024.11.13.623357

    researchmap

  • Luminance and chromaticity discrimination sensitivities right after an abrupt decrease in background luminance Reviewed

    Minwoo Son, Takehiro Nagai

    Color Research and Application   50 ( 1 )   25 - 35   2024.7

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

    Abstract

    When we enter a dark place, such as a tunnel, from a bright exterior, our visual sensitivities take some time to adapt to lower light levels. However, there have been few reports on how quickly luminance and chromaticity discrimination sensitivities recover in this situation. This study aims to quantify the time course of discrimination sensitivity for luminance and chromaticity directions after an abrupt decrease in background luminance. In each trial, the background luminance was decreased from 100 to 1 cd/m2. Subsequently, one target and three reference stimuli of different colors were presented under four stimulus‐onset asynchrony (SOA) conditions. The participants discriminated the target stimulus from reference stimuli. The results showed that discrimination sensitivity was the lowest right after the background luminance changed and gradually improved with SOAs. The sensitivity decreases differed across color directions, with the greatest decrease in luminance, a moderate decrease in S−(L + M), and a negligible change in L−M. However, statistically significant differences were observed only between luminance and L−M, suggesting that the sensitivity decrease after the abrupt decrease in background luminance did not significantly differ between the chromaticity directions. We speculate that these results stem from the interaction between chromatic perception and luminance adaptation, and possibly from rod intrusions.

    DOI： 10.1002/col.22950

    researchmap

  • Increasing magnitude of color differences amplifies category effects Reviewed International journal

    Kashi Li, Takehiro Nagai

    Scientific Reports   14 ( 1 )   13665 - 13665   2024.6

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    Abstract

    Previous studies have identified differences in sensitivity characteristics between color discrimination and perception of suprathreshold color differences. However, it remains highly unclear how color difference sensitivity changes with increasing magnitudes of color difference along various color hues. This study aimed to quantify the sensitivity transition across various magnitudes of color differences and uncover the underlying mechanisms. Color discrimination sensitivities were measured using an adaptive staircase method for 32 isoluminant pedestal colors in the u'v' chromaticity diagram. For suprathreshold color differences, we employed the Maximum Likelihood Difference Scaling (MLDS) method to measure sensitivity to various color difference levels for the same 32 colors. Our findings confirmed the differences in sensitivity characteristics between discrimination and suprathreshold color difference perception. Furthermore, we observed increased sensitivities at many color category boundaries in suprathreshold color difference perception. By investigating the relation between the category effects and the color difference size levels through a model simulation, our findings suggest that the influence of color categories on the perception of color differences may become more pronounced as the magnitude of color differences increases.

    DOI： 10.1038/s41598-024-64215-0

    researchmap

    Other Link： https://www.nature.com/articles/s41598-024-64215-0.pdf

  • Color discrimination repetition distorts color representations Reviewed International journal

    Suzuha Horiuchi, Takehiro Nagai

    Scientific Reports   14 ( 1 )   9615 - 9615   2024.4

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

    Abstract

    Perceptual learning is the improvement of perceptual performance after repeated practice on a perceptual task. Studies on perceptual learning in color vision are limited. In this study, we measured the impact of color discrimination repetitions at a specific base color on color perception for entire hues. Participants performed five sessions of color discrimination training (200 or 300 trials per session) over five days, at colors on either the negative or positive direction of the L-M color axis, based on group assignment. We administered three color perception assessments (unique hues, color category boundaries, and color appearance) before and after the sessions to evaluate perceptual changes after training. The results showed declines in color discrimination thresholds after training, as expected. Additionally, the training influenced outcomes across all three assessment types. After the training, the perceived color appearance changed near the trained color along the stimulus hue, and some of the unique hues and the color category boundaries moved significantly toward the trained color. These findings indicate that short-term repetitions of color discrimination training can alter color representations in the visual system, distorting color perception around the trained color.

    DOI： 10.1038/s41598-024-60283-4

    researchmap

    Other Link： https://www.nature.com/articles/s41598-024-60283-4.pdf

  • Towards a Psychophysically Plausible Simulation of Translucent Appearance

    Takehiro Nagai, Hiroaki Kiyokawa, Stephen Palmisano, Juno Kim

    SIGGRAPH Asia 2023 Posters   1 - 3   2023.11

    　More details

    Publishing type：Research paper (international conference proceedings)   Publisher：ACM  

    DOI： 10.1145/3610542.3626145

    researchmap

    Other Link： https://dl.acm.org/doi/pdf/10.1145/3610542.3626145

  • The perception of translucency from surface gloss Reviewed International coauthorship International journal

    Hiroaki Kiyokawa, Takehiro Nagai, Yasuki Yamauchi, Juno Kim

    Vision Research   205   108140 - 108140   2023.4

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

    DOI： 10.1016/j.visres.2022.108140

    PubMed

    researchmap

  • Effects of specular roughness on the perception of colour and opacity Reviewed International coauthorship International journal

    Yuyang Cai, Hiroaki Kiyokawa, Takehiro Nagai, Leyla Haghzare, Matthew Arnison, Juno Kim

    Journal of the Optical Society of America A   40 ( 3 )   A220 - A229   2023.3

    　More details

    Language：English   Publishing type：Research paper (scientific journal)  

    Previous studies have shown that information concerning object shape is important for the perception of translucency. This study aims to explore how the perception of semi-opaque objects is influenced by surface gloss. We varied specular roughness, specular amplitude, and the simulated direction of a light source used to illuminate a globally convex bumpy object. We found that perceived lightness and roughness increased as specular roughness was increased. Declines in perceived saturation were observed but were far smaller in magnitude with these increases in specular roughness. There were inverse correlations found between perceived gloss and perceived lightness, perceived transmittance and perceived saturation, and between perceived roughness and perceived gloss. Positive correlations were found between perceived transmittance and glossiness, and between perceived roughness and perceived lightness. These findings suggest that specular reflections influence the perception of transmittance and color attributes, and not just perceived gloss. We also performed follow-up modeling of image data to find that perceived saturation and lightness could be explained by the reliance on different image regions with greater chroma and lower lightness, respectively. We also found systematic effects of lighting direction on perceived transmittance that indicate there are complex perceptual interactions that require further consideration.

    DOI： 10.1364/JOSAA.479972

    PubMed

    researchmap

  • Texture statistics involved in specular highlight exclusion for object lightness perception Reviewed International journal

    Hiroki Nohira, Takehiro Nagai

    Journal of Vision   23 ( 3:1 )   1 - 23   2023.3

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1167/jov.23.3.1

    researchmap

  • The dominating impacts of Helmholtz-Kohlrausch effect on color-induced glossiness enhancement Reviewed

    Kazuto Koizumi, Takehiro Nagai

    Journal of Vision   23 ( 1:11 )   1 - 19   2023.1

    　More details

    Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    researchmap

  • Impact of local luminance contrast on facial skin lightness perception: A psychophysical reverse correlation study using sub-band contrast modulation noise. Reviewed International journal

    Takehiro Nagai, Takuya Okada, Ken Nishino, Natsuko Okiyama

    Vision Research   196 ( 108028 )   1 - 23   2022.7

    　More details

    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    In conventional psychophysical reverse correlation methods using white or pink noise, the luminance noise is added to every pixel. Thus, the image features correlated with perception are often biased toward local mean luminance. Furthermore, spatial frequencies and orientations are represented in the primary visual cortex, which forms the basis of various visual perception. In this study, we proposed a new reverse correlation method using noise that modulated the spatial frequency sub-band contrast and examined its properties in psychophysical experiments on facial skin lightness perception. In the experiment, we asked the observers to compare the perceived skin lightness in a paired comparison manner on face stimuli with increased or decreased spatial frequency sub-band contrasts at random spatial locations. The results showed that the contrasts in the eyes or irises were strongly and positively correlated with the perceived skin lightness in most sub-bands, demonstrating that the proposed method reiterated the findings of previous studies that the sparkle of the irises makes the skin appear lighter. Contrarily, the conventional reverse correlation method using pink noise images was applied to the skin lightness perception. The results indicated that only the local mean luminance in some skin regions, such as the forehead, was correlated with skin lightness perception. In summary, with the proposed method, we found some image features in the facial parts other than the skin mean luminance relevant to skin lightness perception, which are difficult to detect using the conventional method. They are considered complementary given that the proposed method and the conventional method extracted considerably different image features. It depends on the psychophysical tasks and stimuli which one is more appropriate.

    DOI： 10.1016/j.visres.2022.108028

    PubMed

    researchmap

  • Luminance dependency of perceived color shift after color contrast adaptation caused by higher-order color channels. Reviewed International journal

    Takehiro Nagai, Kana Kakuta, Yasuki Yamauchi

    Journal of Vision   22 ( 7:8 )   1 - 17   2022.6

    　More details

    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    Color adaptation is a phenomenon in which, after prolonged exposure to a specific color (i.e. adaptation color), the perceived color shifts to approximately the opposite color direction of the adaptation color. Color adaptation is strongly related to sensitivity changes in photoreceptors, such as von Kries adaptation and cone-opponent mechanisms. On the other hand, the perceptual contrast of colors (e.g. perceptual saturation of the red-green direction) decreases after adaptation to a stimulus with spatial and/or temporal color modulation along the color direction. This phenomenon is referred to as color contrast adaptation. Color contrast adaptation has been used to investigate the representation of colors in the visual system. In the present study, we measured color perception after color contrast adaptation to stimuli with temporal color modulations along complicated color loci in a luminance-chromaticity plane. We found that, after the observers adapted to color modulations with different chromaticities at higher, medium, and lower luminance (e.g. temporal alternations among red, green, and red, each at a different luminance level), the chromaticity corresponding to perceptual achromaticity (the achromatic point) shifted to the same color direction as the adaptation chromaticity in each test stimulus luminance. In contrast, this luminance dependence of the achromatic point shift was not observed after adaptation to color modulations with more complex luminance-chromaticity correspondences (e.g. alternating red, green, red, green, and red, at five luminance levels, respectively). In addition, the occurrence or nonoccurrence of the luminance-dependent achromatic point shift was qualitatively predicted using a noncardinal model composed of channels preferring intermediate color directions between the cardinal chromaticity and luminance axes. These results suggest that the noncardinal channels are involved in the luminance-dependent perceived color shift after adaptation.

    DOI： 10.1167/jov.22.7.8

    PubMed

    researchmap

  • 視覚光学研究がもたらす未来 Invited

    水科晴樹, 坂野雄一, 櫻井将人, 永井岳大, 棚橋重仁, 藤井芳孝, 根岸一平, 前川亮, 松田勇祐, 金成慧, 門野泰長, 森本拓馬, 森本拓馬, 宮西雄太

    光学   51 ( 4 )   169 - 170   2022.4

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    J-GLOBAL

    researchmap

  • Luminance contrast detection is optimized for the large‐scale luminance texture of the surround Reviewed

    Misaki Hayasaka, Takehiro Nagai, Yasuki Yamauchi, Tomoharu Sato, Ichiro Kuriki

    Color Research & Application   47 ( 2 )   271 - 287   2021.8

    　More details

    Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

    Abstract

    Contrast sensitivity functions (CSFs) have been typically measured under persistent adaptation to a uniform background. However, this is an unusual situation, considering that visual scenes in our daily lives are typically filled by objects of various luminance levels in a wide dynamic range. We investigated the interactions between the luminance range of textured adapting background and test luminance (luminance of an immediate surround) to see how the contrast sensitivities adapt to background luminance distributions. The background was a random array of one‐dimensional lines, which had a maximum luminance range of approximately 1:520 000, and the test stimulus was a Gabor patch presented on an immediate uniform surround with various luminance levels. The carrier orientation of the Gabor patch was orthogonal to that of the background lines. In the results, the sensitivity was highest near the mean of background luminance, and the luminance range with the highest sensitivity became wider (i.e., the selectivity of sensitivity optimization weakened) as the background luminance range became larger. This sensitivity optimization was significant mainly in the lower spatial frequency. These results indicate that the overall contrast sensitivity is adjusted to the luminance range of the visual scene and the sensitivity optimization is more flexible in relatively lower spatial frequency.

    DOI： 10.1002/col.22723

    researchmap

    Other Link： https://onlinelibrary.wiley.com/doi/pdf/10.1002/col.22723

  • 質感認識の心理・脳神経機構 Invited

    永井 岳大

    光学   50 ( 8 )   314 - 320   2021.8

    　More details

    Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：東京 : 日本光学会  

    CiNii Books

    CiNii Research

    researchmap

    Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I031702703

  • Spatial frequency effective for increasing perceived glossiness by contrast enhancement Reviewed International journal

    Hiroaki Kiyokawa, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    Frontiers in Psychology   12 ( 625135 )   1 - 14   2021.2

    　More details

    Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

    It has been suggested that luminance edges in retinal images are potential cues for glossiness perception, particularly when the perception relies on low-luminance specular regions. However, a previous study has shown only statistical correlations between luminance edges and perceived glossiness, not their causal relations. Additionally, although specular components should be embedded at various spatial frequencies depending on the micro-roughness on the object surface, it is not well understood what spatial frequencies are essential for glossiness perception on objects with different micro-roughness. To address these issues, we examined the impact of a sub-band contrast enhancement on the perceived glossiness in the two conditions of stimuli: the Full condition where the stimulus had natural specular components and the Dark condition where it had specular components only in dark regions. Object images with various degrees of surface roughness were generated as stimuli, and their contrast was increased in various spatial-frequency sub-bands. The results indicate that the enhancement of the sub-band contrast can significantly increase perceived glossiness as expected. Furthermore, the effectiveness of each spatial frequency band depends on the surface roughness in the Full condition. However, effective spatial frequencies are constant at a middle spatial frequency regardless of the stimulus surface roughness in the Dark condition. These results suggest that, for glossiness perception, our visual system depends on specular-related information embedded in high spatial frequency components but may change the dependency on spatial frequency based on the surface luminance to be judged.

    DOI： 10.3389/fpsyg.2021.625135

    PubMed

    researchmap

  • Hue selectivity of collinear facilitation Reviewed

    Tomoharu Sato, Takehiro Nagai, Ichiro Kuriki

    Journal of the Optical Society of America A   37 ( 4 )   A154 - A162   2020.3

    　More details

    Language：English   Publishing type：Research paper (scientific journal)  

    researchmap

  • Luminance edge is a cue for glossiness perception based on low-luminance specular components Reviewed

    Hiroaki Kiyokawa, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    Journal of Vision   19 ( 12:5 )   1 - 22   2019.12

    　More details

    Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    researchmap

  • Contrast sensitivity functions measured on luminance-variegated background Reviewed

    Misaki Hayasaka, Takehiro Nagai, Tomoharu Sato, Tomonori Tashiro, Yasuki Yamauchi, Ichiro Kuriki

    Journal of Vision   19 ( 8 )   100 - 100   2019.7

    　More details

    Publishing type：Research paper (scientific journal)   Publisher：Association for Research in Vision and Ophthalmology (ARVO)  

    DOI： 10.1167/19.8.100

    researchmap

  • 質感研究の最前線「質感の視覚心理物理学」 Invited

    永井岳大

    映像情報メデイア学会誌   73 ( 3 )   418 - 421   2019.5

    　More details

    Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • Relative contributions of low- and high-luminance components to material perception Reviewed

    Takehiro Nagai, Yuta Hosaka, Tomoharu Sato, Ichiro Kuriki

    Journal of Vision   18 ( 13:6 )   1 - 19   2018.12

    　More details

    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    researchmap

  • Task-relevant Perceptual Learning for Judgments of Visual Material Features Reviewed

    KIYOKAWA Hiroaki, KAWASHIMA Yuki, YAMAUCHI Yasuki, NAGAI Takehiro

    Transactions of Japan Society of Kansei Engineering   17 ( 2 )   309 - 319   2018.1

    　More details

    Authorship：Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Kansei Engineering  

    There have been growing interests in clarifying perceptual mechanisms for different material features such as glossiness and transparency in recent years. In this study, we examined whether perceptual learning effects can be observed for material perceptions, and whether active conduct of material judgment tasks is important for the learning effects. The observers were divided into two groups; the glossiness group and the transparency group. The former observers repeated a glossiness discrimination task, while the latter observers repeated a transparency discrimination task for 10 days. We measured changes in correct response ratios and reaction times for discriminations of learned and unlearned material features between before and after the learning. In the results, in both learning groups, the reaction times for the learned material features were significantly shortened after the learning. These results suggest that the human visual system can increase glossiness and transparency discrimination performances by actively repeating material discrimination tasks.

    DOI： 10.5057/jjske.tjske-d-18-00019

    CiNii Research

    researchmap

    Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17H01809/

  • 日本視覚学会 若手の会主催 視覚実験プログラムワークショップ開催報告

    天野薫, 澤山正貴, 山本健太郎, 永井岳大

    VISION   29 ( 2 )   67 - 70   2017.9

    　More details

    Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • Trained visual art experts make more stable judgments of glossiness Reviewed

    Yusuke Tani, Ryo Nishijima, Kowa Koida, Takehiro Nagai, Michiteru Kitazaki, Shigeki Nakauchi

    The Japanese Journal of Psychonomic Science   36 ( 3 )   17 - 29   2017.9

    　More details

    Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Japanese Psychonomic Society  

    <p>We investigated what visual artists learn during sketch training by comparing 3 groups (Experts, Trainees, and Novices). In 2 tasks (congruence detection and glossiness judgment), we manipulated the specular reflection component of bumpy glossy surface images by angular rotation and asked participants to compare original and modified versions. Effects of task order and type were not significant for Experts, while congruence detection improved the glossiness judgment of Novices and reduced that of Trainees. However, congruence detection did not differ by task order or group. Thus, although sketch training did not affect visual discrimination in figural congruence and gloss, it influenced the relationship between glossiness and highlight–shading congruence.</p>

    DOI： 10.14947/psychono.36.3

    researchmap

  • ヒューマンインフォメーションの研究動向「2.1 質感認知」「2.2 色覚」 Invited

    永井岳大

    映像情報メデイア学会誌   71 ( 6 )   839 - 840   2017.6

    　More details

    Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)  

    researchmap

  • Do specular highlights and the daylight locus act as cues for estimating illumination color from a single object? Reviewed

    Takehiro Nagai, Shigeyuki Kaneko, Yuki Kawashima, Yasuki Yamauchi

    Optical Review   24 ( 1 )   47 - 61   2017.2

    　More details

    Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

    DOI： 10.1007/s10043-016-0295-6

    Web of Science

    researchmap

▼display all

Books

  • 人間インタラクション計測ハンドブック

    産業技術総合研究所情報・人間工学領域人間情報インタラクション研究部門（ Role： Joint author2.2.26 質感）

    朝倉書店  2025.11  （ ISBN:9784254201840 ）

    　More details

    Total pages：xvii, 561p   Language：Japanese   Book type：Scholarly book

    CiNii Books

    researchmap

  • 感覚・知覚心理学ハンドブック

    和気, 典二, 重野, 純, 村上, 郁也（ Role： Joint author第Ⅱ部視覚 第６章色覚）

    誠信書房  2025.3  （ ISBN:9784414305050 ）

    　More details

    Total pages：xxxi, 1756p   Language：Japanese   Book type：Scholarly book

    CiNii Books

    researchmap

  • 質感科学ハンドブック

    小松英彦, 富永昌治, 西田眞也（ Role： Joint author1-3節 質感認識の心理）

    東京大学出版会  2025.1  （ ISBN:9784130603256 ）

    　More details

    Language：Japanese   Book type：Scholarly book

    researchmap

  • 感覚知覚の心理学

    吉澤達也（ Role： Joint author12.2節 視覚的質感知覚）

    朝倉書店  2023.4  （ ISBN:9784254520347 ）

    　More details

    Language：Japanese   Book type：Scholarly book

    researchmap

  • 図説視覚の事典

    日本視覚学会（ Role： Joint author2.6節 色覚機能と色の見え）

    朝倉書店  2022.11  （ ISBN:9784254102949 ）

    　More details

    Total pages：vi, 357p   Language：Japanese   Book type：Scholarly book

    CiNii Books

    researchmap

  • 有斐閣現代心理学辞典

    （ Role： Joint author）

    有斐閣  2021.2  （ ISBN:9784641002661 ）

    　More details

    Total pages：996p, 図版 [18] p   Language：Japanese   Book type：Scholarly book

    researchmap

▼display all

Presentations

  • HMD color calibration and color constancy in VR

    DUAY Killian, 溝上陽子, 永井岳大

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Event date： 2025.1

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • 照明分光分布による色恒常性の変化の要因

    岡本夕奈, 永井岳大

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Event date： 2025.1

    Language：Japanese   Presentation type：Poster presentation  

    researchmap

  • 半透明感に対する形状認識のトップダウン効果 International coauthorship

    永井岳大, 清川宏暁, Juno Kim

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Event date： 2025.1

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 半透明感知覚における知覚次元

    渡辺琉翔, 中島健太, 永井岳大

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Event date： 2025

    Language：Japanese   Presentation type：Poster presentation  

    researchmap

  • 脳波デコーディングに基づく視覚野の色選択性の解析

    JIANG Weihang, 永井岳大, 栗木一郎

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Event date： 2025

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 脳波からの質感判別に対する時間的態度の影響

    中島健太, 永井岳大

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Event date： 2025

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • 注意による色差判断への干渉-色差の大きさ間での比較-

    李夏渓, 永井岳大

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Event date： 2025

    Language：Japanese   Presentation type：Poster presentation  

    researchmap

  • The impact of temporal attitudes on physical and affective material impressions – an analysis using EEG International conference

    Kenta Nakajima, Takehiro Nagai

    The 16th Asia-Pacific Conference on Vision (APCV 2024)  2024.7 

    　More details

    Event date： 2024.7

    Language：English   Presentation type：Poster presentation  

    researchmap

  • ipRGCの明るさ知覚への寄与における色相依存性

    木下凪, 鈴木雅洋, 増田修, 内川惠二, 永井岳大

    日本色彩学会第55回全国大会[福岡]’24  2024.6 

    　More details

    Event date： 2024

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • 色の世界は変わる:色弁別の経験に起因する知覚色の変容

    永井岳大, 堀内涼葉

    日本色彩学会第55回全国大会[福岡]’24  2024.6 

    　More details

    Event date： 2024

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • 目・唇の局所的輝度・色成分による肌の明るさ感の変化

    三好健太, 永井岳大

    映像情報メディア学会ヒューマンインフォメーション研究会  2024.11 

    　More details

    Event date： 2024

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • 照明分光分布の違いによる背景色変化が色恒常性に与える影響

    岡本夕奈, 永井岳大

    日本色彩学会第55回全国大会[福岡]’24  2024.6 

    　More details

    Event date： 2024

    Language：Japanese   Presentation type：Oral presentation (general)  

    researchmap

  • 抽象画の色彩選好に関わる色彩特徴~機械学習モデルによる解析~

    花田郁斗, 永井岳大

    日本色彩学会第55回全国大会[福岡]’24  2024.6 

    　More details

    Event date： 2024

    Language：Japanese   Presentation type：Poster presentation  

    researchmap

  • 光沢感知覚に対する輝度ダイナミックレンジの影響

    佐藤美晴, 永井岳大

    日本視覚学会2024年夏季大会  2024.9 

    　More details

    Event date： 2024

    Language：Japanese   Presentation type：Poster presentation  

    researchmap

  • 色弁別の知覚学習による色表象の歪み

    堀内涼葉, 永井岳大

    Vision  2024 

    　More details

    Event date： 2024

    researchmap

  • 肌印象判断におけるヒトと深層学習の方略の差異

    道具優花, 西野顕, 渡辺直樹, 櫻井航洋, 沖山夏子, 永井岳大

    Vision  2024 

    　More details

    Event date： 2024

    researchmap

  • Classification Images法によるCollinear Facilitationの知覚的テンプレートの解析

    佐藤智治, 永井岳大

    Vision  2024 

    　More details

    Event date： 2024

    researchmap

  • 照明環境の演光沢感性における物体条件依存性

    井上大暉, 永井岳大

    Vision  2024 

    　More details

    Event date： 2024

    researchmap

  • まぶしさに対する虹彩透過光の影響

    鈴木雅洋, 永井岳大, 増田修, 内川惠二

    Vision  2024 

    　More details

    Event date： 2024

    researchmap

  • 色度情報による半透明感増加効果に対する物体の厚みの影響

    高梨瑞希, 永井岳大

    Vision  2024 

    　More details

    Event date： 2024

    researchmap

  • 色刺激に対する定常状態視覚誘発電位と心理物理的誘目性の定量的比較

    森下佳徳, 栗木一郎, 永井岳大

    Vision  2024 

    　More details

    Event date： 2024

    researchmap

  • Towards a psychophysically plausible simulation of translucent appearance International coauthorship International conference

    Takehiro Nagai, Hiroaki Kiyokawa, Stephen Palmisano, Juno Kim

    SIGGRAPH Asia 2023  2023.12 

    　More details

    Event date： 2023.12

    Language：English   Presentation type：Poster presentation  

    Country：Australia  

    researchmap

  • Image features involved in translucency enhancement by chromaticity information International conference

    Mizuki Takanashi, Takehiro Nagai

    2023 OSA Fall Vision Meeting  2023.10 

    　More details

    Event date： 2023.12

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Luminance and chromaticity discrimination sensitivities following a sudden decrease in background luminance International conference

    Minwoo Son, Takehiro Nagai

    2023 OSA Fall Vision Meeting  2023.10 

    　More details

    Event date： 2023.12

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Poster Session II: Spillover effects of color discrimination training on color category boundaries and color appearance International conference

    Suzuha Horiuchi, Takehiro Nagai

    2023 OSA Fall Vision Meeting  2023.10 

    　More details

    Event date： 2023.12

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Image Features and Perception of Object Surface Qualities Invited International conference

    Nagai Takehiro

    The 29th International Display Workshops  2022.12  International Display Workshops General Incorporated Association

    　More details

    Event date： 2022.12

    Language：English   Presentation type：Symposium, workshop panel (nominated)  

    researchmap

  • Perceived Glossiness Based on Low-Luminance Specular Components Can Be Increased by Enhancing Luminance Edge Contrasts

    Hiroaki Kiyokawa, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    I-PERCEPTION  2019.9 

    　More details

    Event date： 2019.9

    Language：English  

    researchmap

  • Effects of specular highlight on color constancy are not entirely caused by low-level image features

    Takehiro Nagai, Tomokazu Ishikawa, Tomonori Tashiro, Yasuki Yamauchi

    Journal of Vision  2019.7  Association for Research in Vision and Ophthalmology (ARVO)

    　More details

    Event date： 2019.7

    researchmap

  • Contrast sensitivity functions measured on luminance-variegated background

    Misaki Hayasaka, Takehiro Nagai, Tomoharu Sato, Tomonori Tashiro, Yasuki Yamauchi, Ichiro Kuriki

    Journal of Vision  2019.7  Association for Research in Vision and Ophthalmology (ARVO)

    　More details

    Event date： 2019.7

    researchmap

  • Contributions of luminance and S-cone signals to color discrimination and supra-threshold color difference in color-deficient observers

    Takehiro Nagai, Kyohei Hayashi, Yuki Kawashima, Yasuki Yamauchi, Shoji Sunaga

    Journal of Vision  2017.12  Association for Research in Vision and Ophthalmology (ARVO)

    　More details

    Event date： 2017.12

    researchmap

  • Glossiness Perception not Depending on Specular Highlights-Impacts of Luminance Edges

    Hiroaki Kiyokawa, Tomonori Tashiro, Yuki Kawashima, Yasuki Yamauchi, Takehiro Nagai

    I-PERCEPTION  2017.10 

    　More details

    Event date： 2017.10

    Language：English  

    researchmap

  • A novel method to evaluate the closeness of two colors

    Yasuki Yamauchi, Yusuke Iida, Yuki Kawashima, Takehiro Nagai

    Journal of Vision  2017.6  Association for Research in Vision and Ophthalmology (ARVO)

    　More details

    Event date： 2017.6

    researchmap

  • Effects of luminance levels and chromaticities on perception of continuous color shift

    Kazutoshi Takahashi, Yuki Kawashima, Takehiro Nagai, Yasuki Yamauchi

    Journal of Vision  2017.6  Association for Research in Vision and Ophthalmology (ARVO)

    　More details

    Event date： 2017.6

    researchmap

  • Color appearance influenced by color experiences Invited International conference

    Takehiro Nagai

    Symposium on color vision and facial skin color  2024.7 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    researchmap

  • Comparison of physiological response between led and OLED during task execution International conference

    Takumi Otsuka, Tomonori Tashiro, Yuki Kawashima, Takehiro Nagai, Yasuki Yamauchi

    CIE 2018 Conference on Smart Lighting  2018.4 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Impacts of lower- and higher-luminance components on the material perception. International conference

    Yuta Hosaka, Takehiro Nagai, Tomoharu Sato, Ichiro Kuriki

    2017 OSA Fall Vision Meeting  2017.10 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Simulation of total luminous flux measurement for panel light source using integrating sphere International conference

    Tomonori Tashiro, Taka-aki Suzuki, Yuki Kawashima, Takehiro Nagai, Yasuki Yamauchi

    CIE Midterm Meeting 2017  2017.10 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    researchmap

  • Chromatic selectivity of collinear facilitation International conference

    Tomoharu Sato, Takehiro Nagai, Ichiro Kuriki

    OSA Fall Vision Meeting 2018  2018.9 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Influences of L/M cone number ratio on luminance detection characteristics International conference

    Ryusuke Saito, Takehiro Nagai, Tomonori Tashiro, Yasuki Yamauchi, Keiji Uchikawa

    The 14th Asia-Pacific Conference on VISION (APCV 2018)  2018.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Image cues for glossiness perception obtained from low luminance specular reflection components International conference

    Hiroaki Kiyokawa, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    41st European Conference on Visual Perception  2018.8 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Effects of specular highlight on color constancy are not entirely caused by low-level image features International conference

    Takehiro Nagai, Tomakazu Ishikawa, Tomonori Tashiro, Yasuki Yamauchi

    OSA Fall Vision Meeting 2018  2018.9 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Contrast sensitivity functions measured on luminance-variegated background International conference

    Misaki Hayasaka, Takehiro Nagai, Tomoharu Sato, Tomonori Tashiro, Yasuki Yamauchi, Ichiro Kuriki

    OSA Fall Vision Meeting 2018  2018.9 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Uniformity evaluation metrics for OLED lighting International conference

    Yasuki Yamauchi, Yuki Kawashima, Takehiro Nagai

    The 8th Lux Pacifica  2018.3 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • What factors mediate individual differences in color matching? International conference

    Atsushi Konno, Kunihiro Hatakeyama, Yuki Kawashima, Tomonori Tashiro, Takehiro Nagai, Yasuki Yamauchi

    13th AIC International Congress  2017.10 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Contributions of luminance and S-cone signals to color discrimination and supra-threshold color difference in color-deficient observers International conference

    Takehiro Nagai, Kyohei Hayashi, Yuki Kawashima, Yasuki Yamauchi, Shoji Sunaga

    2017 OSA Fall Vision Meeting  2017.10 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Glossiness perception not depending on specular highlights −impacts of luminance edges−. International conference

    Hiroaki Kiyokawa, Tomonori Tashiro, Yuki Kawashima, Yasuki Yamauchi, Takehiro Nagai

    The 13th Asia-Pacific Conference on Vision (APCV 2017)  2017.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    researchmap

  • Removing attention deteriorates the judgment of large color differences International conference

    Li Kashi, Takehiro Nagai

    The 16th Asia-Pacific Conference on Vision (APCV 2024)  2024.7 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Country：Singapore  

    researchmap

  • Enhancement of perceived skin lightness through facial feature modifications in a brief glance at a face

    Takehiro Nagai, Kana Koizumi, Kenta Miyoshi

    The 56th Annual Meeting of the Color Science Association of Japan  2025.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • The role of color distribution rarity in color preferences for abstract paintings: a machine learning analysis International conference

    Ikuto Hanada, Takehiro Nagai

    The 17th Asia-Pacific Conference on Vision (APCV 2025)  2025.6 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Sydney   Country：Australia  

    researchmap

  • 輝度検出とそのノイズ効果に対するL/M錐体数比の影響

    齋藤隆介, Takehiro Nagai, 田代知範, yasuki yamauchi, KEIJI UCHIKAWA

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Distortion of Color Representations in Working Memory Induced by Two-Color Configurations

    Tomoharu Sato, Takehiro Nagai, Ichiro Kuriki

    2025 Summer Meeting of the Vision Society of Japan  2025.9 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 質感知覚における低／高輝度成分の重要性を決定づける画像特徴

    保坂侑汰, Takehiro Nagai, 佐藤智治, 栗木一郎

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Understanding Visual Psychophysics Invited

    Takehiro Nagai

    The 61st Annual Meeting of the Japanese Society of Ophthalmological Optics  2025.8 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • HDR背景上におけるコントラスト感度特性

    早坂美咲, Takehiro Nagai, 佐藤智治, 栗木一郎

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • HMD color calibration and a color constancy study in VR Invited International conference

    Killian Duay, Yoko Mizokami, Takehiro Nagai

    Symposium “HMD color calibration and a color constancy study in VR”, The 17th Asia-Pacific Conference on Vision (APCV 2025)  2025.6 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    Venue：Sydney   Country：Australia  

    researchmap

  • 透明感と光沢感の知覚学習により低次画像特徴への感度は変化するか？

    小松柊斗, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Comparison of color directions in simple reaction time following an abrupt decrease in background luminance International conference

    Minwoo Son, Takehiro Nagai

    The 17th Asia-Pacific Conference on Vision (APCV 2025)  2025.6 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Sydney   Country：Australia  

    researchmap

  • Psychophysical approach for evaluation of OLED panel performance Invited International conference

    Yasuki Yamauchi, Yuki Kawashima, Tomonori Tashiro, Takehiro Nagai

    CIE 2018 Conference on Smart Lighting  2018.4 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    Venue：Tainan   Country：Taiwan, Province of China  

    researchmap

  • Changes in Strategies for Color-Difference Judgment Depending on the Magnitude of Stimulus Color Differences

    Takehiro Nagai, Kashi Li

    Human Information Research Group, The Institute of Image Information and Television Engineers  2025.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 質感知覚における画像サンプル群依存性

    三澤隆太, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Are Head-Mounted Displays Effective for Investigating the Relationship Between Gloss Perception and Lighting Environments?

    Ryosuke Kawahara, Takehiro Nagai

    2025 Summer Meeting of the Vision Society of Japan  2025.9 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 1型／2型色覚の閾上色差知覚におけるS錐体情報の過小評価

    Takehiro Nagai, 林恭平, yuki kawashima, yasuki yamauchi, 須長正治

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • How Fixated Regions Contribute to the Skin Brightness Illusion

    Kenta Miyoshi, Takehiro Nagai

    2025 Summer Meeting of the Vision Society of Japan  2025.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 輝度知覚に対する微弱コントラスト刺激による順応効果

    鈴木利佳, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Image Features Underlying the Enhancement of Translucency Perception by Chromaticity Information

    Rintaro Oda, Takehiro Nagai

    2025 Summer Meeting of the Vision Society of Japan  2025.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Relationship between the brightness perception and macular pigment density

    Tomonori Tashiro, Ryosuke Sato, Takehiro Nagai, Yasuki Yamauchi

    日本色彩学会第49回全国大会[大阪]'18  2018.6 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Influence of L/M cone ratio on luminance detection characteristics

    Ryusuke Saito, Takehiro Nagai, Yasuki Yamauchi, Tomonori Tashiro, Keiji Uchikawa

    日本色彩学会第49回全国大会[大阪]'18  2018.6 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Time course of color perception after an abrupt decrease in background luminance

    Minwoo Son, Takehiro Nagai

    Human Information Research Group, The Institute of Image Information and Television Engineers  2025.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 視覚の心理物理学 Invited

    Takehiro Nagai

    放送大学面接授業  2017.12 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • 有彩色色度が光沢感知覚に与える影響?自然な色分布を持つ物体表面における検討?

    Kazuto Koizumi, Takehiro Nagai

    日本視覚学会2023年冬季大会  2023.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 色弁別の知覚学習による様々な色知覚課題への波及効果

    Suzuha Horiuchi, Takehiro Nagai

    日本視覚学会2023年冬季大会  2023.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 異常3色覚における輝度弁別とS色弁別の相対感度

    林恭平, Takehiro Nagai, yuki kawashima, yasuki yamauchi, 須長正治

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 連続的色度変化検出特性と色弁別特性の非等価性の検証

    高橋和敏, yuki kawashima, Takehiro Nagai, yasuki yamauchi

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 自然画像における色彩の稀有性と抽象画の色彩選好の関係

    Ikuto Hanada, Takehiro Nagai

    日本色彩学会第54回全国大会  2023.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 条件等色の不成立と黄斑色素濃度の関係

    畠山邦広, 今野敦司, yuki kawashima, Takehiro Nagai, yasuki yamauchi

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 白目の色が顔印象に及ぼす影響についての検討

    渡辺直樹, 西野顕, Natsuko Okiyama, Takehiro Nagai

    第18回日本感性工学会春季大会  2023.3 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 低次画像特徴に依存する質感属性 ?刺激呈示時間と画像特徴欠落の影響?

    山田尚純, yuki kawashima, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 色弁別の知覚学習による色カテゴリーの変化

    Takehiro Nagai, Suzuha Horiuchi

    映像情報メディア学会ヒューマンインフォメーション研究会  2023.2 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 半透明感知覚に対する色度情報の寄与

    Mizuki Takanashi, Takehiro Nagai

    日本視覚学会2023年冬季大会  2023.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 輝度検出におけるL/Mノイズ効果量比とL/M錐体信号寄与比の関連

    齋藤隆介, Takehiro Nagai, yuki kawashima, yasuki yamauchi, KEIJI UCHIKAWA

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 背景輝度急低下時の輝度・色度弁別特性

    Minwoo Son, Takehiro Nagai

    日本視覚学会2023年夏季大会  2023.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 光沢ハイライトによる色恒常性への寄与は低次画像特徴に起因するのか？

    道上隼人, yuki kawashima, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 物体画像から生じる質感・感性の脳波による判別の試み

    Kenta Nakajima, Takehiro Nagai

    日本視覚学会2023年夏季大会  2023.9 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 素材カテゴリプライミングにより質感判断は変化するか？

    桑村将大, yuki kawashima, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 定常状態視覚誘発電位に反映される色覚特性の検討

    Yoshinori Morishita, 栗木一郎, Takehiro Nagai

    日本視覚学会2023年夏季大会  2023.9 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 低輝度領域に起因する光沢感?周辺環境の映り込みの効果?

    清川宏暁, yuki kawashima, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • ディスプレイの低輝度表示特性に適した観察条件と画像条件

    Takemichi Aso, 國枝未夢, Takehiro Nagai

    映像情報メディア学会 2023年年次大会  2023.8 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 異なる色域を考慮した色再現における色の近さ評価法の検討

    浅間崇晃, yuki kawashima, Takehiro Nagai, yasuki yamauchi

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Spillover effects of color discrimination training on color category boundaries and color appearance International conference

    Suzuha Horiuchi, Takehiro Nagai

    2023 OSA Fall Vision Meeting  2023.10 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Seattle   Country：United States  

    researchmap

  • 様々な素材サンプルの質感判断における低／高輝度成分依存性

    保坂侑汰, Takehiro Nagai, 佐藤智治, 栗木一郎

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 視環境における色分布の稀有性と抽象画色選好の関係

    Takehiro Nagai, Ikuto Hanada

    日本視覚学会2023年夏季大会  2023.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 多様な大きさの色差知覚に対する色カテゴリーの影響

    Kashi Li, Takehiro Nagai

    日本視覚学会2023年夏季大会  2023.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 視覚による質感判断における低次画像特徴への依存性 －暖かさ判断は色に基づく？－

    Takehiro Nagai, 山田尚純, yuki kawashima, yasuki yamauchi

    日本色彩学会第48回全国大会[東京]'17  2017.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 抽象画の色彩選好に関わる色彩特徴 ～機械学習モデルによる解析～

    Ikuto Hanada, Takehiro Nagai

    日本色彩学会第55回全国大会  2024.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 画像から質感や素材を推理する ?画像特徴と素材認知? Invited

    Takehiro Nagai

    視覚科学技術コンソーシアム（VSAT）10周年記念イベント講演会  2017.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • Color appearance influenced by color experiences Invited International conference

    Takehiro Nagai

    Symposium on color vision and facial skin color  2024.6 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    Venue：Chiba   Country：Japan  

    researchmap

  • 様々な「大きな色の違い」の見え方 ?多型色覚者の色覚２? Invited

    Takehiro Nagai

    視覚科学技術コンソーシアム（VSAT）10周年記念イベント講演会  2017.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • Classification Images法によるCollinear Facilitation の知覚的テンプレートの解析

    Tomoharu Sato, Takehiro Nagai

    日本視覚学会2024年冬季大会  2024.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 照明空間の印象に対する有機EL照明の影響

    坂野要輔, yuki kawashima, Takehiro Nagai, yasuki yamauchi

    日本視覚学会2017年冬季大会  2017.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Towards a psychophysically plausible simulation of translucent appearance International conference

    Takehiro Nagai, Hiroaki Kiyokawa, Stephen Palmisano, Juno Kim

    SIGGRAPH Asia 2023  2023.12 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Sydney   Country：Australia  

    researchmap

  • 積分球を用いたパネル光源の全光束測定手法の検討

    田代知範, 鈴木敬明, yuki kawashima, Takehiro Nagai, yasuki yamauchi

    平成29年度照明学会全国大会  2017.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 低次画像特徴に基づいて知覚される質感属性とは何か Invited

    Takehiro Nagai

    生理学研究所研究会「視知覚の総合的理解を目指して ～生理学、心理物理学、計算論～」  2017.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • 光沢感知覚に対する輝度ダイナミックレンジの影響

    Miharu Sato, Takehiro Nagai

    日本視覚学会2024年夏季大会  2024.9 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 色の個人差と個人差を生み出す要因に関する研究

    今野敦司, 畠山邦広, yuki kawashima, 田代知範, Takehiro Nagai, yasuki yamauchi

    日本色彩学会第48回全国大会[東京]'17  2017.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Removing attention deteriorates the judgment of large color differences International conference

    Kashi Li, Takehiro Nagai

    The 16th Asia-Pacific Conference on Vision  2024.7 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

    researchmap

  • 照明光色の黒体軌跡からの色差が快適性・作業性に与える影響

    田代知範, 三浦佑樹, Takehiro Nagai, yasuki yamauchi

    日本色彩学会第48回全国大会[東京]'17  2017.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • The impact of temporal attitudes on physical and affective material impressions ? an analysis using EEG International conference

    Kenta Nakajima, Takehiro Nagai

    The 16th Asia-Pacific Conference on Vision  2024.7 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Singapore   Country：Singapore  

    researchmap

  • 視覚心理物理学的応答時間から見る質感知覚と感性生起の階層構造

    Takehiro Nagai, Fuminori Totsuka

    映像情報メディア学会ヒューマンインフォメーション研究会  2022.2 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 色弁別の知覚学習による色カテゴリー境界の変化

    Suzuha Horiuchi, Takehiro Nagai

    日本視覚学会2022年冬季大会  2022.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 光沢知覚に適する照明環境要因の探索的検討

    Kenya Makihira, Takehiro Nagai

    日本視覚学会2022年冬季大会  2022.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 半透明感を生起させる画像情報の解明 －光沢成分と陰影成分を用いたモデル化－

    清川宏暁, yasuki yamauchi, Takehiro Nagai, Juno Kim

    日本色彩学会令和３年度秋の研究会旬間（研究会大会）  2021.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • サブバンド変調逆相関法による光沢感知覚方略の検討

    Akifumi Saeki, Takehiro Nagai

    映像情報メディア学会ヒューマンインフォメーション研究会  2021.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • ディスプレイ上での高コントラスト化と動作情報の付与による金属光沢感の知覚精度向上

    田崎海渡, 佐々木信, Takehiro Nagai

    第23回日本感性工学会大会  2021.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 明度知覚におけるハイライト除去に関わる画像特徴?PS統計量に基づく解析?

    Hiroki Nohira, Takehiro Nagai

    日本視覚学会2022年冬季大会  2022.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 有彩色付与による明るさ感の増加が光沢感増大に与える影響

    Kazuto Koizumi, Takehiro Nagai

    日本視覚学会2022年冬季大会  2022.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 視覚情報処理における質感と感性の階層構造?応答時間による推定?

    Fuminori Totsuka, Takehiro Nagai

    日本視覚学会2022年冬季大会  2022.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • PS統計量ノイズを用いた顔肌の明るさ感と関連する輝度統計量の逆相関解析

    Chiho Kosone, Takehiro Nagai, Hirohiko Kaneko, 西野顕, Natsuko Okiyama

    日本視覚学会2022年冬季大会  2022.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • ディスプレイの低輝度階調表現と色域が画像感性評価に与える影響の検討

    Takemichi Aso, Takehiro Nagai, 張鳴暁

    映像情報メディア学会ヒューマンインフォメーション研究会  2022.3 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Image features and perception of object surface qualities Invited International conference

    Takehiro Nagai

    The 29th International Display Workshops  2022.12 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    Venue：Fukuoka   Country：Japan  

    researchmap

  • 視覚に基づく質感知覚の特性 Invited

    Takehiro Nagai

    2022年度照明学会  2022.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • 色弁別の知覚学習がカテゴリカル色知覚を変化させる

    Suzuha Horiuchi, Takehiro Nagai

    日本色彩学会第53回全国大会[名古屋]'22  2022.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • "演光沢感性"に関わる照明環境特性の探索

    Takehiro Nagai, Kenya Makihira

    日本色彩学会第53回全国大会[名古屋]'22  2022.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 1型・2型色覚の色知覚へのS錐体情報の寄与

    Masaharu Taniguchi, Takehiro Nagai

    日本色彩学会色覚研究会  2022.3 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Interactions in the material appearance of colored semi-opaque 3D objects simulated on generic computer displays International conference

    Yuyang Cai, Hiroaki Kiyokawa, Takehiro Nagai, Leyla Haghzare, Matthew Arnison, Juno Kim

    The 29th International Display Workshops  2022.12 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Fukuoka   Country：Japan  

    researchmap

  • ハイライト領域のHelmholtz-Kohlrausch効果が有彩色表面における光沢感を上昇させる

    Kazuto Koizumi, Takehiro Nagai

    映像情報メディア学会ヒューマンインフォメーション研究会  2022.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • PS統計量ノイズを用いた顔肌の明るさ感と関連する画像統計量の解析

    Chiho Kosone, Takehiro Nagai, Hirohiko Kaneko, 渡辺直樹, 西野顕, Natsuko Okiyama

    映像情報メディア学会ヒューマンインフォメーション研究会  2022.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 明度知覚戦略とCAMによって可視化したVAEの明度推定戦略の比較

    Hiroki Nohira, Takehiro Nagai

    日本視覚学会2022年夏季大会  2022.10 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 視対象の色差の大きさによる色差知覚の感度特性の変化

    伊藤雄謙, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 1型・2型色覚の色知覚における輝度信号と色信号の役割について

    長澤一翔, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 明度知覚におけるハイライト分離の周波数限界

    Hiroki Nohira, Takehiro Nagai

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 色方向と空間周波数の組み合わせに対する随伴性色順応はあるか？

    角田佳菜, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • サブバンドコントラスト変調ノイズによる逆相関法～顔の明るさ評価を例に～

    Takuya Okada, Ken Nishino, Natsuko Okiyama, Takehiro Nagai

    日本視覚学会2020年夏季大会  2020.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 照明環境による質感知覚変化に関する予備検討～質感属性、形状、運動による違い～

    Kenya Makihira, Takehiro Nagai

    日本視覚学会2020年夏季大会  2020.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 刺激呈示時間の短縮に伴う質感知覚方略の変容

    瀬野了斗, 細川研知, 田代知範, yasuki yamauchi, Takehiro Nagai

    映像情報メディア学会ヒューマンインフォメーション研究会  2020.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 色相変化に対する弁別感度と閾上色差知覚感度の違い

    伊藤雄謙, 田代知範, yasuki yamauchi, Takehiro Nagai

    映像情報メディア学会ヒューマンインフォメーション研究会  2020.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Manipulation of glossiness perception by contrast enhancement of high spatial frequency components International conference

    Hiroaki Kiyokawa, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    Vision Sciences Society 2020 Annual Meeting  2020.10 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：United States  

    researchmap

  • サブバンドコントラスト強調による光沢感の上昇ー暗い光沢物体画像での特異な空間周波数特性ー

    Hiroaki Kiyokawa, Tomonori Tashiro, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2020年夏季大会  2020.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 色度情報付与による光沢感増大効果はなぜ生じるのか？

    Kazuto Koizumi, Yuma Watanabe, Takehiro Nagai

    日本色彩学会第52回全国大会'21  2021.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 顔の肌明るさ感に関わる画像特徴を見出す心理物理学的逆相関法 －ノイズの種類の影響に着目して－

    Takehiro Nagai, Takuya Okada, Chiho Kosone, 西野顕, Natsuko Okiyama

    日本色彩学会第52回全国大会'21  2021.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • What factors determine the effects of color on perceived gloss? -Helmholtz-Kohlrausch effect vs highlight-shading color contrast- International conference

    Kazuto Koizumi, Yuma Watanabe, Takehiro Nagai

    Vision Sciences Society 2021 Annual Meeting  2021.5 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Online   Country：United States  

    researchmap

  • 光沢と陰影の3次元形状の違いから生まれる半透明感?2次元画像情報を用いた知覚モデル化?

    清川宏暁, yasuki yamauchi, Takehiro Nagai, Juno Kim

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 有彩色付与による光沢感増大効果を生み出す知覚的・画像的要因

    Kazuto Koizumi, Yuma Watanabe, Takehiro Nagai

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 光沢感知覚と三次元形状知覚の時間特性の比較

    槙遼太郎, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Effects of the surface-undulation spatial frequency on perceptual highlight removal for lightness perception International conference

    Hiroki Nohira, Takehiro Nagai

    Vision Sciences Society 2021 Annual Meeting  2021.5 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Online   Country：United States  

    researchmap

  • PS 統計量ノイズを用いた逆相関法による顔の明るさ感を生む画像要因の抽出

    Chiho Kosone, Ken Nishino, Natsuko Okiyama, Takehiro Nagai

    映像情報メディア学会ヒューマンインフォメーション研究会  2021.3 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 様々な質感知覚の画像特徴依存性の刺激呈示時間による変化

    瀬野了斗, 細川研知, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Color space distortion induced by perceptual learning on color discrimination

    Yilin Zhong, Takehiro Nagai

    日本視覚学会2021年冬季大会  2021.1 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Perceptual dynamics for diffuse-specular spatial congruence in gloss perception International conference

    Ryotaro Maki, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    The 15th Asia-Pacific Conference on Vision (APCV 2019)  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Relationship between image statistics and psychophysical dynamics of perception of various surface qualities International conference

    Ryoto Seno, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    The 15th Asia-Pacific Conference on Vision (APCV 2019)  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Color adaptation to temporal color modulations along complicated loci in the chromaticity-luminance plane International conference

    Kana Kakuta, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    The 15th Asia-Pacific Conference on Vision (APCV 2019)  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Sensitivity to different levels of supra-threshold color difference International conference

    Yuken Ito, Sato Tomoharu, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    The 15th Asia-Pacific Conference on Vision (APCV 2019)  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Estimation of difference in unified material-appearance yielded by color and gloss of a surface International conference

    Kenji Kagitani, Takehiro Nagai, Tomohisa Matsumoto, Keiji Uchikawa

    The 15th Asia-Pacific Conference on Vision (APCV 2019)  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Perceived glossiness based on low-luminance specular components can be increased by enhancing luminance edge contrasts International conference

    Hiroaki Kiyokawa, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    The 15th Asia-Pacific Conference on Vision (APCV 2019)  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Contrast sensitivity functions measured under different dynamic range widths International conference

    Misaki Hayasaka, Takehiro Nagai, Tomoharu Sato, Tomonori Tashiro, Yasuki Yamauchi, Ichiro Kuriki

    The 15th Asia-Pacific Conference on Vision (APCV 2019)  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Effects of specular reflection components on color constancy Invited International conference

    Takehiro Nagai

    The 15th Asia-Pacific Conference on Vision  2019.7 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    Venue：Osaka   Country：Japan  

    researchmap

  • Color contrast adaptation to temporal variations on complex luminance-chromaticity loci International conference

    Takehiro Nagai, Kana Kakuta, Tomonori Tashiro, Yasuki Yamauchi

    The 25th symposium of the International Colour Vision Society  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Latvia  

    researchmap

  • Hue selectivity of collinear facilitation with and without luminance noise International conference

    Tomoharu Sato, Takehiro Nagai, Ichiro Kuriki

    The 25th symposium of the International Colour Vision Society  2019.7 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Latvia  

    researchmap

  • 色順応の輝度依存性 ?脳内色表現の多チャンネル性と色の見え?

    Takehiro Nagai, Kana Kakuta, Tomonori Tashiro, Yasuki Yamauchi

    日本色彩学会第51回全国大会[京都]'20  2020.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 背景の輝度分布がコントラスト感度関数に与える影響

    早坂美咲, Takehiro Nagai, Tomoharu Sato, 田代知範, yasuki yamauchi, 栗木一郎

    映像情報メディア学会ヒューマンインフォメーション研究会  2020.2 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 色と光沢の知覚が統合質感に与える影響

    鎰谷賢治, Takehiro Nagai, KEIJI UCHIKAWA

    日本視覚学会2020年冬季大会  2020.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 輝度エッジ強調による光沢感操作が有効となる物理的・画像的条件

    Hiroaki Kiyokawa, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    日本視覚学会2020年冬季大会  2020.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 視覚感性?色知覚と質感のメカニズムを探る? Invited

    Takehiro Nagai

    第56回日本眼光学学会総会  2020.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • 照明色度と作業依存による空間印象の変化

    渡邊直人, 田代知範, Takehiro Nagai, yasuki yamauchi

    照明色度と作業依存による空間印象の変化  2019.9 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 確率的誤差補償法による画質への影響

    佐藤一輝, 佐藤智治, 小林健一, Takehiro Nagai, 栗木一郎

    Optics & Photonics Japan 2019  2019.12 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Towards consistent color appearance - evaluation of closeness of color images with a trendline International conference

    Tomonori Tashiro, Yuto Nakamura, Yuta Terashima, Syori Yamada, Takehiro Nagai, Yasuki Yamauchi

    The 5th Asia Color Association Conference  2019.11 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Aichi   Country：Japan  

    researchmap

  • Do color matching functions explain individual differences in color appearance? International conference

    Yasuki Yamauchi, Tomonori Tashiro, Yuki Kawashima, Atsushi Konno, Kunihiro Hatakeyama, Takehiro Nagai

    AIC 2019 Midterm Meeting: Color and Landscape  2019.10 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Country：Argentina  

    researchmap

  • 錐体数比と輝度・色知覚 Invited

    Takehiro Nagai

    第21回日本感性工学会大会 企画セッション「視覚感性を支える初期視覚」  2019.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • Cultural Differences in Similarity Judgments of Translucent Objects

    Ruka Watanabe, Juno Kim, Takehiro Nagai

    2026 Winter Meeting of the Vision Society of Japan  2026.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Effects of Experimental Tasks on Measured Brightness in Psychophysical Experiments: The Case of the Facial Parts Illusion

    Nanako Miura, Takehiro Nagai

    2026 Winter Meeting of the Vision Society of Japan  2026.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Stimulus Shape Dependence of EEG-Based Color Decoding

    Keimei Onodera, Takehiro Nagai

    2026 Winter Meeting of the Vision Society of Japan  2026.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Hue-Dependent Effects of Melanopsin on Brightness Perception

    Nagi Kinoshita, Takehiro Nagai, Osamu Masuda

    2026 Winter Meeting of the Vision Society of Japan  2026.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 0 Changes in glossiness perception due to lighting conditions -interaction with head movement, binocular disparity, and wide field of view-

    Ryosuke Kawahara, Takehiro Nagai

    Human Information Research Group, The Institute of Image Information and Television Engineers  2026.2 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Relationship between the contribution of the melanopsin signal to brightness and the stimulus hue

    Nagi Kinoshita, Takehiro Nagai, Osamu Masuda

    Human Information Research Group, The Institute of Image Information and Television Engineers  2026.2 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Visual Features Contributing to Chromaticity-Induced Translucency Enhancement

    Rintaro Oda, Takehiro Nagai

    Human Information Research Group, The Institute of Image Information and Television Engineers  2026.2 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Task-Dependent Color Constancy Measurements in a VR Environment

    Keishi Tomoeda, Takehiro Nagai

    2026 Winter Meeting of the Vision Society of Japan  2026.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Color Calibration for Head-Mounted Displays Invited International conference

    Duay Killian, Yoko Mizokami, Takehiro Nagai

    The 32nd International Display Workshops  2025.12 

    　More details

    Language：English   Presentation type：Oral presentation (invited, special)  

    Venue：Hiroshima   Country：Japan  

    researchmap

  • The role of color distribution rarity in color preferences for abstract paintings-A machine learning analysis-

    Ikuto Hanada, Takehiro Nagai

    Human Information Research Group, The Institute of Image Information and Television Engineers  2025.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 色弁別学習の課題間転移における視野位置依存性の検討

    Kimitaka Ishiguro, Takehiro Nagai

    日本色彩学会第57回全国大会  2026.6 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • Task Dependency in Perceptual Lightness Experiments of Facial Skin: Manifestation and Suppression of Illusion Effects

    Nanako Miura, Kenta Miyoshi, Takehiro Nagai

    The 57th Annual Meeting of the Color Science Association of Japan  2026.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 言語圏による「質感」の捉え方の違い -半透明性物体の場合-

    Takehiro Nagai, Ruka Watanabe, Juno Kim

    日本色彩学会第57回全国大会  2026.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • The impact of temporal attitudes on physical and affective material impressions International conference

    Kenta Nakajima, Takehiro Nagai

    Vision Sciences Society 2026 Annual Meeting  2026.5 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Florida   Country：United States  

    researchmap

  • The possible role of real-world color distribution rarity in aesthetic preference for abstract paintings: A machine-learning approach International conference

    Ikuto Hanada, Takehiro Nagai

    Vision Sciences Society 2026 Annual Meeting  2026.5 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Florida   Country：United States  

    researchmap

  • Material perceptual space for translucent objects: a comparison between Australian and Japanese observers International conference

    Takehiro Nagai, Ruka Watanabe, Juno Kim

    Vision Sciences Society 2026 Annual Meeting  2026.5 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Florida   Country：United States  

    researchmap

  • The Influence of Holistic Processing and Gaze Location on the Perception of Facial Skin Brightness

    Kenta Miyoshi, Takehiro Nagai

    Human Information Research Group, The Institute of Image Information and Television Engineers  2026.2 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Image cues for glossiness perception obtained from low luminance specular reflection components International conference

    Hiroaki Kiyokawa, Tomonori Tashiro, Yasuki Yamauchi, Takehiro Nagai

    41st European Conference on Visual Perception  2018.8 

    　More details

    Language：English   Presentation type：Poster presentation  

    Venue：Trieste   Country：Italy  

    researchmap

  • Influence of chromaticity of illumination on impression of a living room International conference

    Naoto Watanabe, Tomonori Tashiro, Takehiro Nagai, Yasuki Yamauchi

    The 4th Asia Color Association Conference  2018.12 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Thailand  

    researchmap

  • Effects of the wavelength of the primary for the metameric color matching International conference

    Atsushi Konno, Tomonori Tashiro, Takehiro Nagai, Yasuki Yamauchi

    The 4th Asia Color Association Conference  2018.12 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Thailand  

    researchmap

  • Chromatic selectivity of colinear facilitation International conference

    Tomoharu Sato, Takehiro Nagai, Ichiro Kuriki

    2018 OSA Fall Vision Meeting  2018.9 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Nevada   Country：United States  

    researchmap

  • プライマリ波長の変更による条件等色への影響

    今野敦司, 田代知範, Takehiro Nagai, yasuki yamauchi

    日本視覚学会2018年夏季大会  2018.8 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 黄斑色素濃度の個人差が明るさ知覚に与える影響

    ?橋絵里, 田代知範, Takehiro Nagai, yasuki yamauchi

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 質感知覚における課題依存的な知覚学習

    Takehiro Nagai, 小松柊斗, 清川宏暁, 田代知範, yasuki yamauchi

    映像情報メディア学会ヒューマンインフォメーション研究会  2018.12 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Effect of macular pigment density on brightness perception of colored light International conference

    Tomonori Tashiro, Takehiro Nagai, Yasuki Yamauchi

    The 4th Asia Color Association Conference  2018.12 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Country：Thailand  

    researchmap

  • Whiteness enhancement using the watercolor effect International conference

    Shoko Isawa, Tomonori Tashiro, Takehiro Nagai, Yasuki Yamauchi

    The 4th Asia Color Association Conference  2018.12 

    　More details

    Language：English   Presentation type：Poster presentation  

    Country：Thailand  

    researchmap

  • 光反応性の検出に有効な生理的指標の検討

    赤沼里奈, 大塚拓海, 田代知範, Takehiro Nagai, yasuki yamauchi

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 1 型・2 型色覚の閾上色差知覚における輝度信号と S 錐体信号の足し合わせ特性

    長澤一翔, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 短時間呈示刺激に対する色の見えとL/M錐体数比の関係性

    齋藤隆介, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 光沢感知覚におけるハイライト位置整合性処理の時間特性

    槙遼太郎, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 複雑な色輝度時間変動に対する順応特性

    角田佳菜, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 素材認知に対する高/低輝度成分の寄与の非対称性

    保坂侑汰, Takehiro Nagai, 田代知範, yasuki yamauchi, Tomoharu Sato, 栗木一郎

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 背景の輝度分布がコントラスト感度関数に与える影響

    早坂美咲, Takehiro Nagai, Tomoharu Sato, 田代知範, yasuki yamauchi, 栗木一郎

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 色と光沢が同時に異なる物体の統合質感の差の定量化と対象依存性

    鎰谷賢治, Takehiro Nagai, Tomohisa Matsumoto, KEIJI UCHIKAWA

    第123回日本画像学会年次大会  2019.7 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 実物体の色・光沢統合質感の差の定量化

    鎰谷賢治, Tomohisa Matsumoto, Takehiro Nagai, KEIJI UCHIKAWA

    日本色彩学会色覚研究会  2019.3 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 心理物理実験から得られる質感知覚特性における刺激サンプル数依存性

    瀬野了斗, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 色差量の変化に伴う色感度特性の推移

    伊藤雄謙, Tomoharu Sato, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2019年冬季大会  2019.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 「色差のあれこれ」「質感と低次画像特徴」 Invited

    Takehiro Nagai

    視覚科学技術コンソーシアム（VSAT）平成29年度第一回メンバーイベント  2017.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • 脳波からの質感判別に対する時間的態度の影響

    Kenta Nakajima, Takehiro Nagai

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Simulation of total luminous flux measurement for panel light source using integrating sphere International conference

    Tomonori Tashiro, Taka-aki Suzuki, Yuki Kawashima, Takehiro Nagai, Yasuki Yamauchi

    CIE Midterm Meeting 2017  2017.10 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Venue：Jeju   Country：Korea, Republic of  

    researchmap

  • 半透明感に対する形状認識のトップダウン効果

    Takehiro Nagai, 清川宏暁, Juno Kim

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 有機ＥＬを用いた照明空間の印象に関する研究

    坂野要輔, yuki kawashima, 田代知範, Takehiro Nagai, yasuki yamauchi

    平成29年度照明学会全国大会  2017.9 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • HMD color calibration and color constancy in VR

    Killian Duay, 溝上陽子, Takehiro Nagai

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Language：English   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 目・唇の局所的輝度・色成分による肌の明るさ感の変化

    Kenta Miyoshi, Takehiro Nagai

    映像情報メディア学会ヒューマンインフォメーション研究会  2024.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 脳に学ぶ情報処理 Invited

    Takehiro Nagai

    出前講義（大館国際情報学院高校）  2017.12 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • Color Vision Research in Australia: Research Frameworks and Case Studies Invited

    Takehiro Nagai

    ICD（International Colour Day）2025  2025.3 

    　More details

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

    Country：Japan  

    researchmap

  • 生理的応答を用いた作業に及ぼす光源の影響

    大塚拓海, 田代知範, yuki kawashima, Takehiro Nagai, yasuki yamauchi

    平成29年度照明学会全国大会  2017.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 注意による色差判断への干渉 ?色差の大きさ間での比較?

    Kashi Li, Takehiro Nagai

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 確率的誤差補償法による高ダイナミックレンジ画像表示システムの開発

    佐藤智治, Takehiro Nagai, 栗木一郎

    映像情報メディア学会ヒューマンインフォメーション研究会  2017.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 半透明感の知覚次元

    Ruka Watanabe, Takehiro Nagai

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 輝度検出におけるL/M錐体比の効果 ?ノイズ効果と寄与比?

    齋藤隆介, Takehiro Nagai, 田代知範, yasuki yamauchi, KEIJI UCHIKAWA

    映像情報メディア学会ヒューマンインフォメーション研究会  2017.11 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 背景輝度急低下時の色に対する単純反応時間

    Minwoo Son, Takehiro Nagai

    日本視覚学会2025年冬季大会  2025.1 

    　More details

    Language：Japanese   Presentation type：Poster presentation  

    Country：Japan  

    researchmap

  • 色恒常性に対する光沢感と低次画像統計量の影響の比較

    石川智和, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • 光沢感知覚における鏡面ハイライト以外の画像手掛かり?映り込みの明瞭さと輝度エッジの関係?

    清川宏暁, 田代知範, yasuki yamauchi, Takehiro Nagai

    日本視覚学会2018年冬季大会  2018.1 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

  • Comparison of simple reaction times among color directions under an abrupt decrease in background luminance

    Minwoo Son, Takehiro Nagai

    The 56th Annual Meeting of the Color Science Association of Japan  2025.6 

    　More details

    Language：Japanese   Presentation type：Oral presentation (general)  

    Country：Japan  

    researchmap

▼display all

Awards

  • Paper Award

    2026.6   The Color Science Association of Japan   Luminance and chromaticity discrimination sensitivities right after an abrupt decrease in background luminance

    Minwoo Son, Takehiro Nagai

    　More details

    Award type：Honored in official journal of a scientific society, scientific journal  Country：Japan

    researchmap

  • 2025 JOSA A Emerging Researcher Best Paper Prize

    2026.6   Optica   Impact of field of view on color constancy in virtual reality

    Killian Duay

    　More details

    Award type：Honored in official journal of a scientific society, scientific journal  Country：United States

    researchmap

  • Presentation Encouragement Award, 57th Annual Meeting

    2026.6   The Color Science Association of Japan  

    Kimitaka Ishiguro

    　More details

    Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

    researchmap

  • Journal of Vision Exceptional Review

    2026.2   Journal of Vision  

    Takehiro Nagai

    　More details

    Award type：Honored in official journal of a scientific society, scientific journal  Country：United States

    researchmap

  • Best Presentation Award

    2026.2   Human Information Research Group, The Institute of Image Information and Television Engineers  

    Nagi Kinoshita

    　More details

    Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

    researchmap

  • Best Presentation Award, 2026 Winter Meeting

    2026.1   Vision Society of Japan  

    Ruka Watanabe

    　More details

    Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

    researchmap

  • Best Presentation Award, 2025 Winter Meeting

    2025.1   Vision Society of Japan  

    Kenta Nakajima

    　More details

    Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

    researchmap

  • 2023年夏季大会 ベストプレゼンテーション賞

    2023.9   日本視覚学会  

    孫旻佑

    　More details

  • Journal of Vision Exceptional Review

    2023.7   Journal of Vision  

    　More details

  • 第54回全国大会発表奨励賞

    2023.6   日本色彩学会  

    花田郁斗

    　More details

  • ベストプレゼンテーション賞

    2022.11   映像情報メディア学会ヒューマンインフォメーション研究会  

    小泉和人

    　More details

  • 第53回全国大会発表奨励賞

    2022.6   日本色彩学会  

    堀内涼葉

    　More details

  • 2022年冬季大会ベストプレゼンテーション賞

    2022.1   日本視覚学会  

    野平博希

    　More details

  • 色彩科学系5研究会合同研究発表会 優秀発表奨励賞

    2021.11   日本色彩学会  

    清川宏暁

    　More details

  • 第52回全国大会発表奨励賞

    2021.6   日本色彩学会  

    小泉和人

    　More details

  • ベストプレゼンテーション賞

    2021.3   映像情報メディア学会ヒューマンインフォメーション研究会  

    小曽根千穂

    　More details

  • 2021年冬季大会 ベストプレゼンテーション賞

    2021.1   日本視覚学会  

    瀬野了斗

    　More details

  • 優秀研究発表賞

    2018.12   映像情報メディア学会  

    齋藤隆介

    　More details

  • 2017年度優秀論文賞

    2018.11   日本基礎心理学会  

    谿雄祐, 西島遼, 鯉田孝和, 永井岳大, 北崎充晃, 中内茂樹

    　More details

    Country：Japan

    researchmap

  • 2018年冬季大会 ベストプレゼンテーション賞

    2018.1   日本視覚学会  

    清川宏暁

    　More details

    Country：Japan

    researchmap

▼display all

Research Projects

  • なぜ一瞬で心を奪われるのか？魅力印象の時間的うつろいと刹那的魅力操作

    Grant number：25K22816  2025.6 - 2028.3

    日本学術振興会  科学研究費助成事業  挑戦的研究(萌芽)

    永井 岳大

    　 More details

    Grant amount：\6240000 （ Direct Cost: \4800000 、 Indirect Cost：\1440000 ）

    researchmap

  • Study on color representation in human cortex based on individual differences in perception and brain activity

    Grant number：24H00702  2024.4 - 2028.3

    JSPS  Grant-in-aid for Scientific Research  Class A

    Ichiro Kuriki, Masami K Yamaguchi, So Kanazawa, Sae Kaneko, Takehiro Nagai, Jiale Yang, Kenichi Ueno, Hiroaki Kiyokawa

    　 More details

    Grant amount：\47710000 （ Direct Cost: \36700000 、 Indirect Cost：\11010000 ）

    researchmap

  • 照明の「演質感性」指標の確立 －感性再現に至適な照明設計技術へ向けて－

    Grant number：23H03484  2023.4 - 2027.3

    日本学術振興会  科学研究費助成事業 基盤研究(B)  基盤研究(B)

    永井 岳大

    　 More details

    Grant amount：\18590000 （ Direct Cost: \14300000 、 Indirect Cost：\4290000 ）

    researchmap

  • 照明の「演質感性」指標の確立 －感性再現に至適な照明設計技術へ向けて－

    Grant number：23K28174  2023.4 - 2027.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    永井 岳大, 吉澤 望

    　 More details

    Grant amount：\18590000 （ Direct Cost: \14300000 、 Indirect Cost：\4290000 ）

    光沢感知覚は、物体表面の光反射特性だけでなく、その三次元形状や照明環境によっても影響を受ける。しかし、照明環境が光沢感知覚に及ぼす影響を定量的に評価する手法は存在しない。この問題に対処するため、2023年度には、多様な照明環境下での光沢感知覚に適した照明環境の要因を明らかにするための方法論を確立することを目指した。
    この目的のために、ヒトが光沢感判断の手がかりとして利用するとされる物体画像の特徴量に基づくモデル（物体モデル）を初めに構築し、このモデルを用いて様々な照明環境下での光沢感知覚量を推定できるようにした。次に、物体モデルによる光沢感推定値を活用することで、多様な照明環境における光沢感を心理実験なしに推定できるようにした上で、その推定値に基づき、照明環境の特徴量から光沢感知覚への照明の影響の強さを説明するモデル（照明モデル）を開発した。最終的に、この照明モデルを用いて、光沢感知覚に適した照明環境の特性を特定した。この方法の利点は、時間とコストを抑えつつ、様々な照明環境下での光沢感を効率的に推定できる点にある。このアプローチにより、広範な応用可能性を持つモデルが作成された。
    最後に、照明モデルの分析により、光沢感知覚に影響を与える照明環境の画像特徴量が検討された。その結果、従来研究で提案された「Brilliance」という特徴量が、先行研究と同様に光沢感との相関を示すことが確認された。さらに、本研究では、より多くの照明環境を用いたことで、これらの示唆が多様な環境に適用可能であることが示された。また、球面調和関数における中程度の周波数成分が、Brilliance以上に照明による光沢感知覚の変化をよく説明することが示された。これにより、光沢感性をより良く説明する新しい照明環境の特徴量が見出される可能性が高まった。

    researchmap

  • 変角光学的要因に基づく「本物らしさ」の質感知覚への能動性の寄与の脳神経機序の解明

    Grant number：23K11290  2023.4 - 2026.3

    日本学術振興会  科学研究費助成事業  基盤研究(C)

    増田 修, 永井 岳大, 児玉 直樹, 栗木 一郎, 長谷川 誠

    　 More details

    Grant amount：\4680000 （ Direct Cost: \3600000 、 Indirect Cost：\1080000 ）

    先行課題と装置を共有しているため、先行課題に連動した遅れが本課題においても生じている。本課題においても、外付けディスプレイ装置を実際にMRI装置内に持ち込んで動作テストを行った。映像自体は特に不具合なく表示されたものの、様々な課題が明らかとなったため、再度、新たな材料を購入して、試作を繰り返しているところである。このディスプレイ装置は、先行課題にも使用されているもので、共同研究者から借用しているものであるが、共同研究者の別の研究プロジェクトで使用していた同じ型のディスプレイ装置が故障して修理に出されることとなり、それに伴って、ディスプレイ装置を一時返却する必要が生じた。ディスプレイ装置の一時返却中、被験者に呈示するための刺激映像の制作を進めた。先行する心理物理実験で使用したのと同じ商品券試料を、電動ゴニオーメータ上に設置して、ディジタルカメラで撮影し、動画ファイルを作成した。この動画ファイルをディスプレイ上に正確な時間タイミングで表示するための自作プログラムを Matlab および Psychtoolbox を用いて作成している。本課題においては、被験者に自分自身で映像の動きを制御させる必要があるため、そのための試作プログラムを作成している。本課題で使用可能な応答キーパッドには、ボタン数の少ないモデルと、ボタン数の多いモデルの2種があり、被験者が混乱することなく正確に応答できる方法や、複数のボタンを同時に押した場合に実際にプログラムから取得可能な応答等を模索して実験プログラムの試作を繰り返している。その後、一時返却していたディスプレイ装置を再び借用できることとなったため、新たな試作スタンドで再びディスプレイ装置の設置を試し、作成した刺激映像を用いて、実際に MRI撮像をしながらの予備実験を早急に開始する予定である。

    researchmap

  • 深層学習と脳波から見る感性的質感生起における物質的質感の役割

    Grant number：23H04337  2023.4 - 2025.3

    日本学術振興会  科学研究費助成事業 学術変革領域研究(A)  学術変革領域研究(A)

    永井 岳大

    　 More details

    Grant amount：\7800000 （ Direct Cost: \6000000 、 Indirect Cost：\1800000 ）

    researchmap

  • 高次質感認知への色の寄与：色覚異常の感性に調和する色デザイン手法の開発

    Grant number：21KK0203  2022.10 - 2024.3

    日本学術振興会  科学研究費助成事業 国際共同研究加速基金(国際共同研究強化(A))  国際共同研究加速基金(国際共同研究強化(A))

    永井 岳大

    　 More details

    Grant amount：\13910000 （ Direct Cost: \10700000 、 Indirect Cost：\3210000 ）

    researchmap

  • 心理物理学・生理学的時間特性に基づく物質的/感性的質感間の階層構造モデリング

    Grant number：21H05810  2021.9 - 2023.3

    日本学術振興会  科学研究費助成事業 学術変革領域研究(A)  学術変革領域研究(A)

    永井 岳大

    　 More details

    Grant amount：\7670000 （ Direct Cost: \5900000 、 Indirect Cost：\1770000 ）

    本研究の目的は、光沢感などの物質的質感と美しさなどの感性的質感の脳内情報処理における関連性を明らかにすることである。具体的には、しばしば仮定される物質的質感と感性的質感の処理間の階層構造が本当に正しいのかを検証する。2021年度は様々な質感を判断する際の応答時間を心理物理学的により計測し、それらの質感の因果関係の手がかりを得ることを目標とした。
    そのため2つの心理物理実験を行った。第1の実験では、様々な物質的質感と感性的質感の心理量の相関関係を明らかにするために、多数の物体画像から構成された刺激群に対し、様々な質感の心理量をサーストンの一対比較法によって計測した。測定した質感は、光沢感、透明感、ざらざら間、しっとり感、温かさ、硬さ、綺麗さ、好き、触りたい、高級感、新しさであった。その結果、多くの物質的質感・感性的質感の心理量の間に相関関係があることを改めて確認することができた。さらに、計測した心理量をもとに、様々な質感の間で回答難易度が統制された刺激対セットを作成することができた。これは、質感の種類間で応答時間を測定するための重要な準備となった。
    実験２では、実験１で作成された刺激対セットを用い、サーストンの一対比較法による心理物理実験において全質感・感性項目の応答時間を計測した。その結果、平均応答時間について質感の種類によって違いがあり、例えば光沢感、ざらざら感、好きといった項目で応答時間が短い傾向にあった。しかし、物質的質感と感性的質感の間に応答時間に有意な違いはなかった。一方、質感の種類の組合せごとに、応答時間の大小により刺激群を分類すると、その間で相関の強さに違いがあった。この情報に基づくことて、脳内情報処理の様々な質感の間の因果関係に関する手がかりを提供できる可能性が示唆された。

    researchmap

  • 色弱者の色知覚と感性認知の多面的研究：視覚的印象を考慮する画像強調技術の開拓

    Grant number：21H03534  2021.4 - 2024.3

    日本学術振興会  科学研究費助成事業 基盤研究(B)  基盤研究(B)

    坂本 隆, 市原 恭代, 永井 岳大, 高橋 直己

    　 More details

    Grant amount：\17030000 （ Direct Cost: \13100000 、 Indirect Cost：\3930000 ）

    researchmap

  • 変角光学的要因に基づく「本物らしさ」の質感知覚における脳神経メカニズムの解明

    Grant number：20K12036  2020.4 - 2023.3

    日本学術振興会  科学研究費助成事業 基盤研究(C)  基盤研究(C)

    増田 修, 永井 岳大, 児玉 直樹, 古川 貴雄, 栗木 一郎, 長谷川 誠

    　 More details

    Grant amount：\4290000 （ Direct Cost: \3300000 、 Indirect Cost：\990000 ）

    実験を開始する準備として必要な装置の購入、設計、試作などを行った。屈折異常のある被験者でも視覚刺激を観察できるようにするため、MRI装置内で使用可能な屈折矯正眼鏡 (MediGlasses Research)を購入したが、この眼鏡は、乱視矯正には対応していないため、別途、プラスチック製の検眼レンズセット、チタン製およびプラスチック製の検眼枠を購入して実際の材質や作りなどを確認した。
    MRI装置に付属の視覚刺激呈示機構 (MR-Theater) を確認したところ、実験に必要な解像度が得られないことが判明したため、別途、視覚刺激呈示装置を外部に付加するよう計画を変更した。これに伴い、MRI対応のディスプレイを共同研究者から借用することにし、このディスプレイと視覚刺激生成用パーソナルコンピュータとをつなぐケーブルの敷設工事を行った。また、このディスプレイをMRI装置内に安定して設置するためのスタンド等の設計を数種類検討した。MRI装置に備え付けのミラーはこの新しく付加したディスプレイには対応していないため、新たにミラーも設置する必要があり、このためにアクリル製のミラーを購入して材質がMRI装置内で安全に使用できるか確認した。このミラーを保持するためのスタンドも新たに作る必要があり、2種類のヘッドコイルのいずれにも対応できるように、何度か試作を繰り返した。
    視覚刺激として呈示する動画を製作するための準備として、電動ゴニオメーターを調整し、その運転プログラムを試作した。実験刺激となる試料を照明するための照明装置を購入し、効果的な照明光の当て方を検討した。

    researchmap

  • 色覚異常における未知の色差知覚特性に立脚した色変換技術の開発

    Grant number：19H04197  2019.4 - 2023.3

    日本学術振興会  科学研究費助成事業 基盤研究(B)  基盤研究(B)

    永井 岳大, 須長 正治, 山内 泰樹, 増田 修

    　 More details

    Grant amount：\17160000 （ Direct Cost: \13200000 、 Indirect Cost：\3960000 ）

    本研究の目的の一つは、1型/2型色覚における、大きなS色差（S錐体の応答により作り出される色差。およそ黄-紫方向）に対する色差知覚特性を明らかにすることである。そこで、R2年度は、なるべく多くの研究協力者の色差知覚特性を測定する計画であった。しかしながら、新型コロナウイルス感染拡大のため、特に学外の実験協力者について心理物理実験の実施が困難となってしまった。そこで、今後の心理物理実験の準備を万全にする，R3年度に実施予定であった実験準備を前倒しで行うなど、当初計画とは大幅に異なる項目を実施した。具体的には以下の通りである。
    【1 心理物理実験の準備】実験協力者を多く確保する準備として、外部機関の研究者の協力を得て、１型/2型色覚の方々が集まるコミュニティとのコネクションを確立した。これにより、今後より多くの実験協力者にご協力いただきやすい環境が構築できた。
    【2 視覚探索実験の準備】本研究課題で着目する閾上色差知覚の特性は、日常生活においては、ターゲットの検出や探索、認識に大きな影響を及ぼすと考えらえる。そこで、日常の課題に対する閾上色差知覚の影響を明らかにするため、色探索の応答時間を計測する実験内容を確定し、また実験環境を整えた。
    【3 三色覚者を対象とした閾上色差知覚メカニズムの検討】閾上色差知覚には色弁別とは異なるメカニズムが関与することを示唆する結果は、本研究課題でもすでに得られていたが、そのメカニズムの詳細はほとんど分かっていなかった。そこで、三色覚者が対象ではあるが、色弁別感度と閾上色差知覚を様々な色に対し詳細に計測した。この実験では、知覚対象とする色差が大きくなるにつれ、その知覚が色カテゴリーにより修飾されていくことを示唆する結果が得られた。この結果から、１型/2型の色差知覚特性においても色カテゴリーの影響を考慮すべきであるという研究上の留意点を見出すことができた。

    researchmap

  • 「脳ならでは」の質感知覚方略：機械学習との画像特徴依存性の類似性と相違性

    Grant number：18H04996  2018.4 - 2020.3

    日本学術振興会  科学研究費助成事業 新学術領域研究(研究領域提案型)  新学術領域研究(研究領域提案型)

    永井 岳大

    　 More details

    Grant amount：\8320000 （ Direct Cost: \6400000 、 Indirect Cost：\1920000 ）

    本研究の目的は、1. 多種多様な質感の中で、ヒトが低次画像特徴に基づいて知覚する質感とは何なのか、2. その低次画像特徴と機械学習が用いる画像特徴の類似性・相似性はどこにあるのか、を明らかにすることであった。
    本研究では、質感知覚に関する心理物理実験と、そのデータと機械学習の対応性解析を行った。まず、心理物理実験では、多数の実サンプルの写真を刺激として用いた。短時間（33.3~150.0 ms）だけ呈示される刺激に対し光沢感、透明感、温度感、重さ感を被験者に判断してもらい、その精度を計測した。その結果、呈示時間が33.3 msのように短くなると、いずれの質感でも判断精度が低下したが、その中でも重さ感だけが精度低下が顕著に大きかった。呈示時間が短いと視覚系が取得できる情報がかなり制限されることから、重さ感以外の質感では、呈示時間が短いときでも単純な画像特徴に基づく判断ができる可能性が示された。
    続いて、この心理物理実験の結果と機械学習の対応関係を解析した。画像認識用のConvolutional Neural NetworkであるAlexNetを解析対象とし、特に単純な画像特徴を取り扱う初期層に着目した。実験刺激に対する初期層の応答を説明変数として、被験者の質感知覚量を説明する回帰モデルを作成した。その結果、光沢感、透明感、温度感では、呈示時間が短い場合でもモデルの決定係数が十分高く維持された一方で、重さ感では呈示時間が短くなるにつれ顕著に決定係数が低下した。この結果から、重さ感以外の質感においては、その知覚における多様な手がかりが画像に含まれ、ヒトは入手可能な画像特徴に応じて戦略を臨機応変に変化させながら質感を知覚していると考えられる。
    最後に、研究テーマから得られた知見の一般化を目指し、刺激サンプル数と質感の数を大幅に増やすため、JavaScript に基づくweb実験環境の構築も行った。

    researchmap

  • Quantification of integrated material perception for real object appearance and constructing its perceptual model based on optical features

    Grant number：17H01809  2017.4 - 2020.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)  Grant-in-Aid for Scientific Research (B)

    Uchikawa Keiji

    　 More details

    Grant amount：\17810000 （ Direct Cost: \13700000 、 Indirect Cost：\4110000 ）

    Appearance of materials is determined by the integration of their surface attributions, such as color, gloss, and texture (integrated material perception). The integrated material perception is essential to determine surface appearance of objects in the real world although the integrated material perception has not been extensively studied. Observers estimated differences in the integrated material perception for real object images which differed in color and gloss. Our prediction model, using lower-order image statistics, showed a high correlation with the subjective estimation of the differences. Furthermore, we measured estimation in appearance differences in color only and gloss only for the same object images. As results, we obtained that the integrated material perception is simply expressed as linear summation of color and gloss difference estimations.

    researchmap

  • Relationship between material image features and color recognition: effect of specular highlight color

    Grant number：15K00372  2015.4 - 2018.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

    Nagai Takehiro

    　 More details

    Grant amount：\4680000 （ Direct Cost: \3600000 、 Indirect Cost：\1080000 ）

    Specular highlights on typical objects reflect illumination colors directly, and thus is a potential cue for color constancy. In this study, we aim to elucidate the relationship between specular highlights and color perception using psychophysical experiments. First, we found no evidence that temporal color changes of specular highlights are recognized as illumination color changes. However, secondly, we showed that color constancy is stronger in scenes containing many glossy objects with specular highlights than in scenes containing only matte objects. Also, this superiority of glossy objects over matte objects disappeared in noise images whose low-level image statistics were the same as glossy objects. These results suggest that there is a mechanism in the human brain that adjusts color appearance according to specular highlight color so that the influences of illumination colors are removed from color appearance.

    researchmap

▼display all