A laser sight is a device attached or integral to a firearm to aid target acquisition. Unlike optical and iron sights where the user looks through the device to aim at the target, laser sights project a beam onto the target, providing a visual reference point.
Although lasers in the visible part of the spectrum are most common, invisible infrared (IR) lasers may be used in conjunction with a night vision device.[1][2] As they are offset from the barrel, laser sights need to be zeroed in, much like a conventional sight, so that the beam intercepts the point of impact at a chosen distance.[3] Devices may include one or both types of laser, with some models also incorporating a rangefinder, flashlight, or IR illuminator.[4] Laser sights may be attached to the existing sighting mechanism, the trigger guard, via a rail system, or can be integrated into replacement components such as the guide rod or grip plates.[5][6][7] Some variants are also incorporated into other attachments such as foregrips.[8]
Laser sights are primarily used by military and law enforcement, although have some civilian use for hunting and self defense. They are also found on some less-lethal weapons, such as Taser electroshock weapons.[9]
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