사진으로 표현된 산업용 광원으로써 PLS광원의 특성 연구

Abstract

Since human visual recognition systems have compensation function to the light intensity and light quality, people can perceive the lightness and color of objects quite accurately regardless of environment. To analyze better expression of color, in this research, followings are covered : 1) relationship among a spectrum, color temperature, and color rendering, 2) causes of different results after between light adaptation and color adaptation, 3) color adaptation time of PLS reference light source, and 4) color interpretation mechanism of visual recognition system of a human. For this research, we used photographic verification to express the color status reproduced by picture image and the reaction for the color after the human system is adapted to the spectrum of light sources under mesopic vision and scotopic vision condition. From our observations, compared with PLS light source which is placed at very off-the-contour to 1 o'clock direction from contour of ideal black object, the HPI light source shows very good results, very close to contour of ideal black object. However, after the histogram adjustment of photo imagery with both PLS and HPI light source (using Adobe Photoshop program), the PLS light source expresses better color rendering indices distribution. As a result, we found out that the source with better color rendering indices distribution leads to better spectrum characteristics, and leads to more accurate color expression. Additionally, from the color adjustment experiments, in case of pupil expression caused by mesopic vision, we observed that since the stimulus information of Rod is mixed with color information of Cone, color adjustment take place simultaneously. Consequently, the color temperature does not present all the color information, and the spectrum of light source has an affect on the color regeneration. In addition, since PLS light source has a linear spectrum, it shows better color expression than discontinuous spectrum light source. The color temperature can give us accurate information only in case that contour shows the characteristics of ideal black object, but the spectrum can provide much more color reconstruction information than color temperature and so color continuity becomes a measure of possibility of accurate description of color. Consequently, all the three information, color temperature, spectrum of light source, color continuity, must be considered in case of accurate expression of color.