The point I was trying to get at was, if the primary intent is to paint a target, a blue laser diode already has a beam distance of some 6.2 miles without a beam expander. My thought was to just use optics to decrease the rectangular shape (using cylindrical lenses) then widen the beam with further optics. Which would be far easier, and have a lot less losses, than exciting some phosphor. It just won’t be white.
I had always wanted a pocket light that could throw a long distance, just because…. And have some ideas of my own how to do it. But when I get to try these out is a while out as I have other projects.