Not only that, try to switch it on and off a couple of times. You'll see that when the blue light is ON after having used the blue filter for like a couple of s

Not only that, try to switch it on and off a couple of times. You'll see that when the blue light is ON after having used the blue filter for like a couple of seconds, you'll feel like someone punching your eyes! It's almost like having a lamp in your face all the time in the night - of course you can't sleep! We just got used to it. Now thankfully someone has implemented such filters.