This doesn't break the glass, but the collision could eventually hurt the birds.
Birds fly into windows for two reasons.
First, they see the reflection of the sky and think it is safe. Second, a male sees his own reflection and thinks the bird he sees is a new male trying to enter his territory, so he tries to fight it. Bird window collisions are traumatic for birds and people alike. There's no easy solution to the problem. Bird scare devices do not work.