I use the lens assembly ( the focusing one ) from an old projector to focus my laser beam down, it burns like hell when I do, focuses it to a tiny point , only works if I shine it in the right end though
yeah, was an old philips, was a nightmare to open, didnt have the proper screw drivers you see :-[ Theres loads of cool optics in them, theres 3 diffraction gratings, a huge beam splitter type thing, loads of polarized glass slides, some block green laser light really well, others block red, theres also loads of other lenses, and a few other cool things
;D The projector still worked, it was just slightly 'wonky' at the edges, it was just one my dad had lying around his work so he brought it home for me, and I used it for a while for gaming, then thought what the hell lets take it apart