Special forces operators use infrared laser sights with night vision goggles to target the enemy. There are several reasons why you should use this combination. One, to provide target acquisition at night. Two, to designate the target for your teammates. In either case, the infrared laser sight prevents the enemies from knowing that they are being targeted, unless the enemies are using nightvison scopes as well.
It would be really cool to use infrared laser sight and nightvision in airsoft games at night. It would certainly provide an unfair advantage. The military infrared laser sights are extremely expensive and is not available to civilians. The civilian versions are still quite costly. But there is actually a way to use standard red laser sights in the same manner. In this article, we will explain how to use a standard red laser sight to achieve similar results to an infrared laser sight.
Laser sights are extremely bright in the dark. The intense and concentrated beam will stand out from a distance. The following photo shows a laser sight that is full-bright.
Honestly, you can't make your red laser sight completely invisible. But you can get really close for this purpose. In this article, we are going to re-define the condition where enemies cannot see your red laser sight dot as "invisible". This "invisibility" provides you the same capability as having an infrared laser.
You can make your red dot sight "invisible" by using batteries that are low on power (almost dead). The batteries should be sufficiently low on power that it turns on the red laser, but not enough to create a bright red dot. In this condition, you can see that the red laser has a glow at the pointer tip (don't point it at your eye), but do not see a bright red dot on the wall. Photo below shows the red tip glow.
Discharging your batteries to the power level described above is the hardest part of this task. The easiest approach is to use battery cells from garage door opener batteries (see the "Eight LR932 Button Cells Inside One A23 Battery" and "Using LR932 Button Cells Inside Laser Sights" articles). The lower power battery cells will power the laser sight at full brightness for a while. But soon after, the energy will be spent and the laser sight will produce the "invisible" effect.
The photo below shows what the naked eye will see when the lasers are aimed at the wall. The full bright laser dot is extremely visible as you'd expect. The dimmed laser dot is barely visible.[placeholder for photo of red laser dot and dimmed red laser dot on the wall with naked eye]
The following photo shows the fully bright red laser dot, shining on the wall, in night vision. As you can see, it is so bright, it causes glare and haze in the gen 1 nightvision. This glare prevents you from seeing anything else in the scene. In fact, I'm suspecting that prolong exposure will damage the intensifier. As you can see, so fully functional red laser is not usable with gen 1 night vision scope.
The following photo shows the dimmed red laser, using low power battery cells. The dimmed red laser dot shows up in the night vision brightly, but doesn't not cause the scene to wash out. The MOA is about the same as that of a red dot sight. Once the laser has been sighted in, you can use this combination as a nightvision aiming scope.[placeholder for photo of dimmed red laser dot in night vision]
The following photo demonstrates what the enemy will see through nightvision when a full-bright red laser is used. As you can see, the full bright laser provides a straight line trace, in outdoor environment that is clearly visible with nightvision goggles.
With night vision goggles, the enemy can follow the red laser trace back to your location, when the see the red laser source (see photo below).
The dimmed red laser on the other hand, does not produce this trace. Instead, the nightvision monocular sees a bright spot in the distance.[placeholder for photo of dimmed red laser]