Preferred illuminance and color temperature in creative works

The improvement of the lighting environment in offices leads to the improvement of intellectual productivity. We constructed a system that provides individual illuminance and color temprature preferred by workers, and we carried an experiment to clarify the favorite illuminance and color temperature in the office. From this experiment, it is found that each person's favorite lighting environment was different each other and it changed by health condition and time in a day. We consider that creative works are improved when workers are provided the their preferred lighting environment.