One of my challenges at Pacific Biosciences was understanding other technical disciplines. I interfaced with chemists, biologists, optics, software, bioinformatics, firmware, electrical engineers. I didn't need to interface with the chemists and biologists all that much, because I was in the "engineering wing" of the R&D. I can write SW to some extent, and can read schematics, but I found optics very difficult. I mistakenly expected to understand optics with just some common sense and basic math and physics. But still, it did not "jell". At that time, I did not understand why the optics engineers gave me that condescending "you just don't understand" look when I asked for explanations. Apparently, the chasm between optics and other branches of engineering has been noticed by others; my work colleague told me that the optics people and photography people don't mix either. I don't know why the chasm is so deep and wide; I have seen optics people try: for example, Richard Szeliski maps (one of the many) mathematical derivations to photography concepts in his book (
Computer Vision: Algorithms and Applications)--and then goes right back to more math. In all the optics books, the math is chastizingly boring; maybe this is what separates the optics professionals from the pretenders/aspirants--like me?
I now realize that I have to understand optics better if I am to continue in the biotech industry. Rather than launch into hard core lens design, I thought I would ease into it by playing around with active light control using DLP. So I got a TI DLP EVM 3010, and wondered how to get a collimated image, and hit a roadblock right away: I don't really understand how the basic projector works; I expected the LED collimators to actually collimate the LEDs, and the focusing module to expand the image downstream of the DLP. Consider this picture of the EVM 3010's optics module, made by eProtech:
The light source is a lone LED sitting on a copper board, drawing a lot of current, as you can see here:
Note that all those pins are positive; the ground is the whole copper board (which has been painted non-reflective), as you can see here:
The copper backplane also has to conduct heat away from the LEDs, so the thermal pad between the back of the copper and the heatsink makes sense.
How much do the 2 convex lenses in front of each LED focus the light? I thought that after the "collimator" above, the RGB sources would be roughly collimated, because the prism/wedge assembly in front of the DMD does NOT seem to magnify, as you can see below (the smaller rectangle on the side facing the DMD just cleans up the light being thrown at the DMD):
My next step will be to really collimate the RGB LEDs at the source, with a parabolic reflectors.
