The lighting that affects human biological rhythms which was mentioned briefly in the previous post is generally referred to as “circadian lighting.” The word “circadian” originating from the Latin words “circa” meaning “approximately” and “diem” meaning “a day.”

Many people have experienced feeling refreshed by the morning sun, whereas feeling sleepy in a darkened room. The biological function of adjusting circadian rhythms through exposure to sunlight continues to occur in the human body today, even after milli…