Infrared Laser Gun Sight

It's possible to replace the standard red laser on your gun sight with an invisible, infrared one.  This will allow you to use common off-the-shelf image-intensifying night vision googles while firing your weapon.

Complete infrared laser diode modules are available from Digi-Key for under $100.  They can be used as a drop in replacement for your current visible light laser diode.

Infrared Laser Diode Modules - Complete Assembly

Voltage: 2.7 to 3 Volts
Power Output: 5 mW
Class: IIIa

Module Size		Wave-		Current		Digi-Key
(mm)			length (nm)	(mA)		Part #		Price
17.02 x 10.44		780		45-70		38-1018-ND	$56.00
17.02 x 10.44		808		60-70		38-1005-ND	$64.00
17.02 x 10.44		850		45-65		38-1019-ND	$68.00
17.25 x 6.4		780		45-70		38-1024-ND	$76.00
17.25 x 6.4		808		60-70		38-1025-ND	$80.00
17.25 x 6.4		850		45-65		38-1026-ND	$88.00

Digi-Key laser diode catalog page in PDF format.

The shorter wavelength modules (780 & 808 nanometers) are cheaper, but can be visible to some people, but should be viewable in all image-intensifying night vision and CCD imaging devices.  The longer wavelength module (850 nanometers) is the best choice, but may be filtered (i.e. not viewable) on some image-intensifying night vision and color CCD imaging devices.

For a really quick hack, you can use the infrared laser diode module from an old laser printer, CD writer or laser fax machine.  These will be non-collimated (i.e. not focused) without their special lens assembly.  They will be effective at shorter ranges though.  Power them as if they where a standard laser module, but be aware some infrared laser diodes are case NEGATIVE (visible laser diodes are case POSITIVE).

K3PGP's list of various laser diode specifications.

Hewlett-Packard (HP) LaserJet IIP Laser Diode Driver Board

It's possible to salvage the IR laser diode and driver board from an old HP LaserJet-type printer.  The IR laser diode comes connected to the driver PC board via a large heatsink, which makes for easy mounting.

Picture of the LaserJet IIP Laser Diode Driver Board  Component side.

Picture of the LaserJet IIP Laser Diode Driver Board  Backside, showing heatsink and collimating assembly.

The pinout to the driver board (the white plastic connector) is as follows:

To power the laser driver board, connect +5 VDC and +8 VDC to Pins 1 & 7, respectively.  Connect Pins 3 & 4 together.  Toggle (via a small switch or push button) Pin 5 to GROUND to turn the laser diode ON.  Current draw is around 50 mA, with an IR laser output of 5 mW (780 nm) or so.


Return to Homebrew Military & Espionage Electronics Page