The general wisdom and some studies seem to point to blue light being really bad before sleep. Some serious scientists even wear blue-blocking visors the last few hours of the day, or use red lightbulbs. And of course there are all the redshift like apps and now built in to the OS stuff to red shift computer screens at night.

So I was surprised that the sleep programs all seem to have a lot of bright blue light.

Is there competing research I am unaware of?

Has anyone made programs that just use red light, or at least avoid blue light?