I've been playing with laser diodes for a short while use the info on this forum alot so i thought i'd join up so i can share the knowledge i've accumilated (hopefully it'll be useful
Currently i've got numerous <5mw red lasers and 2 green laser pointers which i bought new off ebay. The first is a <50mw from a guy in Thailand for about £15 and with the second is a <240mw from another guy in Thailand (probably the same guy but i'm awful with names) for £25. The <50mw is very bright but the <240mw is certainly not 5 times brighter, so i suspect it's closer to 100-150mw, still... Can't complain for only £25
Just made my first homemade laser using a diode gracefully donated by a 4x dvd writer, although i don't have a collomating lens for it so it's still a very led, theres a <1mw red sitting crying out to be butchered for parts. What makes mine slightly different from other peoples laser projects i've seen on here is that the driver circuitry i have was made from components that i ripped off the dvd writer circuit board!
Some parts such as a 47uf cap and some veriable resisters i got from elsewhere as they were convinient but both parts were on the dvd board which means that, with a bit of extra work, i could of made the whole laser setup with no external components ;D
Once i get access to a digital camera i'll take some photos and make a write up on how i did it for other people who are intrested. Given the parts are fairly common it should be possible to make driver circuits from any dvd writer board.
Incase i don't manage to extract a collomating lens intact, does anyone know of a place that sells just the lens units very cheaply? I'm assuming that for dvd writer lasers they will need to be of a higher quality then your £1, 1mw, plastic red laser jobs, but all i can find are very high quality units with very high prices to match.