The purpose of this study is to investigate the lighting condition for the qualitative lighting design of schoolroom in case of seeing blackboard as visual object. The author tries to measure reflected light on the specimen (blackboard and chalk) surface by every 10° incidental angle and incidental azimuth angle. The luminance of reflected light was measured. But, the luminance of the characters on blackboard is irregular according to adhesion of chalk powder. Therfore, the author tries to measure the area ratio of chalk's and blackboard's part, and the contrast of visual object is obtained from this area ratio. The author reveals the reflection characteristics of the position of the light source(Θi, Φ) and the luminance contrast by the area ratio.
