There are sites on the web about light use, that can be manipulated to change your circadian rhythms by changing the time of day to move bedtime hours to a more convenient time.

Also using melatonin on a schedule, one can push back or bring up a sleep time. They use this for pilots and others who cross time zones.

I think light therapy however, is difficult for bipolar patients.
Very tricky. I know one year I was doing seedlings with 4 grow lights, and monitoring them, watering them is intensive for a while until they get sturdy. I inadvertently exposed myself to too much light and became very hyper, and couldn't sleep. I did a series of bird's nest drawings in that state! So it wasn't wasted, but it was pretty zoomy! (This spring I am planning a similar large batch of seedlings for myself, the new garden and my son's house, and his new neighbor. So I might just go into that state again! Who knows? ) I will turn off the lights when attending to the babies this time to protect myself.

This drawing (pastel) won a prize even!