123Splat:
Doc,
What is the optical power output of your 405nm (lowercase, not NM) module, and what driver are you planning to use? If you lower the drive current to just above the lasing threshold, you will get a much lower optical power output (safer to observe target, not direct out of the module, and you still need to watch out for blue light syndrome affects, limit observation time and watch for ghosting).
That is a good question. When I bought the 405nm laser diode over 6 months ago from the cheapest vendor on eBay, I just wanted to see what it could do. After I saw that it could burn black spay paint off a copper sheet, then I knew exactly what I wanted to do with it. There are no certifications or paperwork, I have just a diode in a square black housing, with a fan on the back and the board the came with it.
The cheap kit looks like this:
There are lots of eBay listings for the same kit, and they claim 20mw, 100mw, 200mw - is anyone's guess. I think they are blue-ray laser diodes ? I read alot of threads people use them until they burn out, and then just replace like a consumable. They are probably over-driven, or maybe the heat sink is too small. Nobody wants to make a huge liquid cooled thing with nitrogen, for a $10.00 diode to swap out.
123Splat:
To substitute a 'red dot' for testing/calibration, you will probably need to replace the 405nm setup with a low power red LASER diode(10mW or less, any higher and you should use laser goggles), in a press fit module with a collimating lense, and a suitable current limiting driver (easy to make with a LM317 in current limiting configuration).
lots of help and sources available on Laserpointerforum.com
Ok thanks for the help. I will check out the laserPointerForum, and try to find some of those colum lenses.
For the red diode driver, I just have a 100-ohm 1/4watt resistor, through a 2n2222 transistor. I will need to do my homework for the 405nm diode, since obviously speed is an issue, and charging capacitors with any delay to activating that beam could set off the timing to the spinning mirrors.