What To Do With A 1mW Red Diode

[lamborgini8]

Ok, I have my 75mW green laser now and its incredible. I have taken apart my old cheapy 1mW red laser now and have the diode.

Any ideas on what I can do with it? Or is it just fit for the bin?

While I am posting, my 75mW seams to flicker a little when its on. As soon as its on its very bright but then suddenly dims, the beam and everything is still visible and can instantly burn but it dims. On fresh batteries it doesn't do that, instant burning and solid beam and dot but after about 10 mins of using them it just dims like said above. That 10 mins not being constant of course.

 

[benthegeek]

Batteries drop their voltage with increasing use and show that pulse effect when they are starting to run low. Happens with ordinary torches as well, just a property of batteries. Green lasers use a nonlinear crystal to double the frequency of an IR laser to make it green. To achieve this effect requires migh powers of IR light, so while your laser is outputting 75mW of green, there is most likely 100+mW of IR being generated. Someone with a little more experience with pointers should be able to give you a better figure. Basicly it means green chews thrugh batteries, which is why you see that effect.

As for the red diode, do a little research on AM modulaton of a laser. Can be as simple as adding the ouput of your mp3 player to the battery pumping the diode. The varying music signals cause the intensity of the laser to vary proportionally. Pick it up with a phototransistor, capacitor, resistor and 9v battery and you can get the music signal back. Amplify it an you have music being transmitted on a laser beam.

The attached pic is of my low power basic setup, with the laser missing.