Powering the Laser Diode
Laser diodes need a regulated current. If you just hook one up to a 9V battery, It’s going to suck out as much current as it can. This will cause it to heat up and burn out. One of the components that seems to be used with lasers is the LM317 regulator. It looks like a transistor.
I tried putting together a LM317 Constant Current Circuit on a piece of perf-board, but something went wonky with my schematic or a component I was using. So instead of going to Radio Shack again, (god, I hate that company!) I decided to order a pre-assembled current regulator that would theoretically fit inside the laser enclosure I just bought. It’s called the RkcStr Micro-driver.
It turned out not to fit into my enclosure, but I don’t mind. I think it will just make it easier to heatsink. If not, I can file it down later.