Quote Originally Posted by Aztecphoenix View Post
what about using a series of varying aperatures, with the largest nearest the diode? wouldn't this work similarly but reduce the problem of alignment?
Well, the problem is that as light passes the edge of the aperture, it gets scattered just slightly. So what you want is it have apertures that only interact with the scattered light. The first aperture reduces the beam width, but the edge scatters some of the light right at the edge of the beam. The next aperture is to block the scattered light, but you want it to not touch the rest of the beam. Of course, some of the scattered light does hit the edge of that aperture and scatters again instead, necessitating a third aperture and so forth...

Of couse, two should be enough for the Peachy, since the first one only scatters about 10% of the light at even at a small scale. The next one of course only scatters 10% of that and so on. Two apertures and you've filtered 99% of the scatter.