Evaluation of the perception of visual comfort, reading ability, color appearance, and global preference with respect to the CCT and the illuminance, of a university audience

With the aim of knowing the perception of a university audience of four aspects of lighting: visual comfort, reading ability, color appearance and global preference, 40 volunteers were surveyed, sitting in front of a cubicle, which was illuminated by 12 different states of lighting. The lighting was a combination of illuminances of 100 lx, 200 lx, 400 lx or 600 lx, and a CCT of 3500 K, 5000 K, or 6500 K. The different states of lighting were presented one after another randomly. The results indicate that the CCT does not have a significant influence on visual comfort, reading ability, and global preference and that these aspects depend only on the illuminance: observers prefer illuminances of 400 lx and 600 lx, with no significant difference between them. The color appearance aspect is influenced by illuminance and CCT: observers prefer illuminance values of 400 lx or 600 lx combined with CCTs of 5000 K or 6500 K.