When is a pixel cooler than millions?

While on vacation we went to see a laser show - an old school variety that combines several different lasers of different colors into a single beam, modulates them to create different colors and sends it bouncing off the galvos towards the roof of a planetarium. On a musical score, of course.

When I was a kid, I had no idea how they worked, but the laser shows were awesome. As a young adult hacker, and after friends introduced me to dark magic, I built my own setup. I now know how they work from the deepest guts, and they're no less awesome. These days you can get a capable set of galvos and pilots for a hundred bucks from the Far East, it's fair to say there's no magic left, but the awesomeness still remains. /p>

"laser show" by Ilmicrofono Oggiono

At the same time, lasers and laser shows are extremely retro. The most stunning example of this struck me when tearing apart a Casio projector long ago to extract the brand new, otherwise unobtainable 455nm blue laser diodes. There I was removing a diode from a 24 array from inside the projector and throwing away the incredibly powerful DSP processor, hacking the precision optical path and removing the MEMS DLP mirror array with nearly a million< /em>small mirrors, to replace it with two mirrors, driven by big old wire coil electromagnets. Like a caveman.

But there's still something about a laser show that I've never seen replicated: the insane range of colors they can produce. It is, or may be, much more than the RGB you get from your monitor. Some of the colors you can get from a laser (or prism) are just beautiful in ways I can't explain. I can tell you that you can get them by combining red, blue, green, cyan, and maybe even a dark violet laser.

What you get with a laser show is nothing compared to multi-megapixel projectors, even in a normal movie theater. Heck, you really have one pixel. But if you move it fast enough and accompany it with a decent soundtrack, you still have an experience worth having while you still can.

[Banner image of a very old RGB laser hack. We need more! Send us yours!]