Blue light doesn't focus quite the same as red/yellow so you get two different focal planes for the two images. Our eyes are incredible and they accommodate this difference through software and working harder. If you filter out the blue with yellow or orange lenses then you eye doesn't have to work so hard. This is good for old eyes and for tired eyes as it reduces stress on the muscles. You will get less eye fatigue with these lenses over a long session. Less of in impact for young eyes or folks with very sharp vision.
BTW the prisoner with orange will stand out, the one in blue will look like he is wearing black as the blue is absorbed.
One effect is that when you take them off after a long day, your eyes will bloom like a camera with all the blue light they are suddenly receiving. Everything will have a slightly blue cast for a few minutes. I believe this is due to the chemical imbalance in your retina cells, the blue sensors have not worked all day and have stored up extra chemical sensor for blue. It takes a few minutes for my eyes to adjust to having to focus full spectrum again.
Eliminating blue also cuts glare as there is a lot of uv in reflected glare from the sun. Probably more than you wanted to know but physics is cool.
