[Laser] IR laser from laserjet3

[F1AVYopto at aol.com]

Paul
You can use this laser for laser com  experiments but...
After to have separated the laser with its focusing lens  assy from the 
printer you have to identify the direct bias wires and the sensor  outputs wires on 
the laser diode.
If you have a 1,5V max powered tester (if  more you will kill the laser 
diode) you can try to identify the 3 wires from the  diode.
You will find two diodes effects.
Theses diodes are full isolate in  reverse, the laser diode have the highest 
direct resistor, the PIN photodiode  sensor the lowest direct resistor.
The output voltage tester polarity, when  the highest direct resistor is 
found, identifies the correct laser diode  polarity for the current to drive it. 
You have to build a modulated driver  match to the diode characteristics.
The threshold current is the current that  begin the laser diode to give a 
laser beam.
For a classical printer laser  diode 3 mA more than the threshold current and 
no more is sufficient to get a  few mW. 
To check the output you need an infrared camera and to be very  careful.
May be the link (sorry for the bad  translation).
http://pageperso.aol.fr/YvesF1AVY/UK2.html
could help  you
73 Yves.