Bright light therapy, or just light therapy, can help some people change when they sleep. It can be useful for people who have an irregular sleep-wake cycle. This cycle is also called the circadian rhythm.
Light therapy can be useful for people who have trouble falling asleep or those who wake up earlier than they want to. However, it may be less useful for people who have trouble staying asleep.
Published on Insomnia, a Sleep-Disorders.net community, November 22, 2021