Safe line IR laser which will be seen from 15 meters by camera module
I'm going to put this as an answer, it feels more like a comment. (they are getting too long)

If I was designing a laser system for outdoor use with public access, then I'd have to assume a worse case scenario.  In this case that would be some idiot sticking a screw driver into the spinning mechanism, stopping it, and then looking in to see how it works.  In which case 5mW is too much.  25 uW sound's like a safe number.