Quote from nitro:
I saw this on a science channel.
The idea is, there are two type of sleep disorders, getting up too early, and not being able to go to sleep.
The idea is very very simple, we all have an internal clock, and that clock can get out of sync. It can also be fooled. The internal clock is regulated by light. What you do depends on your condition:
a) If you have trouble going to sleep, what you do is put on sunglasses in the early afternoon. This tricks the internal clock into thinking that it has been night longer, and the brain will do it's job of getting you to sleep "earlier".
b) on the other hand, if you are a person that wakes up to early, you put on the sunglasses on in the morning, and then take them off in the afternoon. This will cause you to fall asleep a little later and therefore waking should also occur later.
Then there are things that have been known for a while, like don't drink caffeine after 5:00 PM, etc.
I don't have sleep disorders, but I decided to experiment on myself and tried a) to see what would happen. It worked!!