Buliding burning laser circuit

I took from a friend's burner the laser diodes(standard one, if that is necessary I can check its label). As I understand- one is supposed to be the RED one, and the other IR. I have a multimeter with diode mode. Last time I've connected it to the diode- it went crazy... can it cause any damage to the diode? will I be able to see light from the red one as with LED?(not looking straight).
After I'll figure out which is the correct diode, What is the simple way to make it work(and burn things)? I know I can't use directly a battery, but I also don't want to buy things for it, just create a simple circuit. also, please don't just give me a sketch, explain it- cause I want to understand what I do.

you can use DMM set to diode test
if you want an inexpensive DIY driver, you can make the DDL driver (with LM317 IC) - use the [SERACH] button
but let us know the type and speed of your DVD RW

Do you mean By DMM -Digital MultiMeter, or different abbreviation?
Just to make sure...

You cannot test laser diodes with a DMM reliably. If you hook up the laser diode in reverse, the voltage can damage the diode, unlike normal diodes laser diodes die pretty easy with a reverse voltage.

Diodes without a lens diverge pretty fast, diodes of a few 10mW (visible, no IR diodes) spread out soon enough that you can test them safety at low powers. Higher power diodes need a bit more caution, don't look into them but point them at a diffuse reflecting object at a small distance.

witch_king said:

Do you mean By DMM -Digital MultiMeter, or different abbreviation?
Just to make sure...

Click to expand...

right

Some DMMs have too high of a voltage on their probes in diode test mode to be safe for LDs.

You need to build yourself the quick and cheap linear current regulator called the DDL or Daedal driver, which is based on the LM317. Lots of info on this here in LPF. Search and read up on it. This limits the current the diode can draw to a safe level. Without this regulator, the LD behaves as a dead short on the power source, instantly draws excessive current, and dies. When soldering an LD to this regulator, always discharge the output capacitor prior to soldering the LD. How fast is your DVD burner that the diode came from? Use search to find the info about drive current for different DVD burner diodes.

If you absolutely need a quick go/no go test for the LD, you can do a quick test with a small lithium battery like CR2 or CR123 and a 33 ohm resistor. Put the resistor in series with the LD and briefly connect the battery. Get the polarity right, LDs don't like being hooked up backwards. If the diode is good, this test will make it lase, but not very strongly. This is a rudimentary test and will not allow burning. If the diode is good, build or buy a driver for it.

To use your diode, it needs to be in an aixiz housing so that it is heatsinked and has a lens to focus the output for burning, etc. If the diode is high-power (like 20x LOC), the aixiz housing will need another heatsink around it, unless you only run for short bursts with cooldown time in between.

Laser diodes require a driver, housing with heatsink, and lens in order to be used. Those who skip anything usually post back about how their diode has now died ...
There are lots of old threads on this forum about "I hooked my LD up to a car battery and now its dead - WHY?" Give your diode what it needs, don't make it become another statistic ...