Night-vision device

A US Navy aviator uses a pair of helmet-mounted AN/AVS-6 vision goggles. The effect on the natural night vision of the eye is evident
A standard telescopic sight augmented with a night-vision device in front on the M110. Note that in addition to the image intensifier, the NVD gathers much more light by its much larger aperture
A 1PN51-2 night-vision reticle with markings for range estimation
First-person view through night-vision goggles of the FBI Hostage Rescue Team using an airboat.

A night-vision device (NVD), also known as a night optical/observation device (NOD) or night-vision goggle (NVG), is an optoelectronic device that allows visualization of images in low levels of light, improving the user's night vision.

The device enhances ambient visible light and converts near-infrared light into visible light which can then be seen by humans; this is known as I2 (image intensification). By comparison, viewing of infrared thermal radiation is referred to as thermal imaging and operates in a different section of the infrared spectrum.

A night vision device usually consists of an image intensifier tube, a protective housing, and an optional mounting system. Many NVDs also include a protective sacrificial lens, mounted over the front/objective lens to prevent damage by environmental hazards,[1] while some incorporate telescopic lenses. An NVD image is typically monochrome green, as green was considered to be the easiest color to see for prolonged periods in the dark.[2] Night vision devices may be passive, relying solely on ambient light, or may be active, using an IR (infrared) illuminator.

Night vision devices may be handheld or attach to helmets. When used with firearms, an IR laser sight is often mounted to the weapon. The laser sight produces an infrared beam that is visible only through an NVD and aids with aiming.[3] Some night vision devices are made to be mounted to firearms. These can be used in conjunction with weapon sights or standalone; some thermal weapon sights have been designed to provide similar capabilities.[4]

These devices were first used for night combat in World War II and came into wide use during the Vietnam War.[5] The technology has evolved since then, involving "generations"[6] of night-vision equipment with performance increases and price reductions. Consequently, though they are commonly used by military and law enforcement agencies, night vision devices are available to civilian users for applications including aviation, driving, and demining.[7]

  1. ^ P, Will (10 August 2021). "Night Vision Devices Releases Lightweight Sacrificial Windows". The Firearm Blog. Archived from the original on 10 August 2021.
  2. ^ Liszewski, Andrew (30 April 2021). "The Army's New Night-Vision Goggles Look Like Technology Stolen From Aliens". Gizmodo. Archived from the original on 30 April 2021. Retrieved 23 May 2021.
  3. ^ Utley, Sean (2020-06-11). "Selecting An IR Laser And Illuminator". Firearms News. Archived from the original on 2020-07-27. Retrieved 2021-01-22.
  4. ^ Lynch, Kyle (15 January 2019). "Why You Should Consider Adding a Clip On Night Vision Device". Tactical Life. Archived from the original on 18 September 2021. Retrieved 23 August 2022.
  5. ^ Tyson, Jeff (27 April 2001). "How Night Vision Works". HowStuffWorks. Archived from the original on 9 June 2022. Retrieved 1 March 2011.
  6. ^ as defined by the US Army Night Vision and Electronic Sensors Directorate (NVESD)
  7. ^ "NVESD About Us". Fort Belvoir, VA: Night Vision & Electronic Sensors Directorate. Archived from the original on 1 February 2010.