The third optical layout had every component mounted in a fixed structure, but we could adjust the beams to meet because we had a hierarchy of adjustments: Each laser diode merely had to be within the corrected field of the first lens, a glass aspheric CD reading lens, and then the 8x magnified image of it could be adjusted more conveniently. We had thermal problems with steel and aluminum, and a lot of weight was starting to hang from the backs of the lasers. By this time we had added the fourth laser, pointed down from above. 012