Psychological Effects of Ambient Illumination Control and Illumination Layout While Viewing Various Video Images

Recently enhancing the visual experience of the user has been a new trend for TV displays. This trend comes from the fact that changes of ambient illuminations while viewing a Liquid Crystal Display (LCD) significantly affect human impressions. However, psychological effects caused by the combination of displayed video image and ambient illuminations have not been investigated. In the present research, we clarify the relationship between ambient illuminations and psychological effects while viewing video image displayed on the LCD by using a questionnaire based semantic differential (SD) method and a factor analysis method. Six kinds of video images were displayed under different colors and layouts of illumination conditions and rated by 15 observers. According to the analysis, it became clear that the illumination control around the LCD with displayed video image, the feeling of „activity‟ and „evaluating‟ were rated higher than the feeling of fluorescent ceiling condition. In particular, simultaneous illumination control around the display and the ceiling enhanced the feeling of „activity,‟ and „evaluating‟ with keeping „comfort.‟ Moreover, the feeling of „activity‟ under the illumination control around the LCD and the ceiling condition while viewing music video image was rated clearly higher than that with natural scene video image. key words: display device, illumination, subjective evaluation, semantic differential (SD) method, factor analysis