About Night Vision Device Equipment

Once limited to military and governmental applications, first-generation night vision equipment is now available for civilian use at a price affordable to many. Night vision devices find practical applications in boating safety, wildlife observation and night photography as well as by forming an unobtrusive part of home security systems. Top quality state-of-the-art versions remain beyond the economic reach of most civilian users.

History

William Edward Spicer developed the first night vision system for the U.S. military in World War II. The infrared-detecting sniper scope fielded during that conflict required target illumination from an external source. The illuminating beam was not detectable by the human eye, but required a searchlight sized emitter mounted on a flatbed truck. Night vision glasses of that era were large aperture binoculars--soldiers used atropine drops to dilate their pupils during use, and the glasses lacked light amplification.

Starlight Scopes

Generation One devices were the first to use electronic amplification of both the visible and infrared spectrum. Converting the photons of natural light images to electron flows, the Starlight devices paint an electronic image on a phosphorus-coated screen. The image seen by the eye is two-dimensional and lacks both color variation and detail. Police and military personnel require special training to be able to use night vision devices effectively in tactical situations.

Microchannel Plates

The introduction of micro-channel plate (MCP) technology in the 1970s greatly improved the resolution of Generation Two devices. Best amplification was increased from 1000x- the optimal for Generation One--to 20000x. In an MCP device, a photo-cathode converts photons of available light to electrons, and the millions of sensor tubes in the MCP amplify the electron flow. Generation Two devices are now commonly used by many police departments.

Thermal Imagery

While devices based on amplification of ambient light are limited in range and do not penetrate fog, rain or smoke, Forward Looking Infrared (FLIR) systems have much greater range and do see through particle barriers. Sensitive to infrared rather than visible light, FLIR has been successfully used for navigation by low-flying aircraft and as targeting technology under difficult battlefield conditions.

Innovations

Gallium arsenide photo-cathodes have improved the amplification of night vision systems to from 30000x to 50000x the ambient light level. Fourth generation devices combining this advancement with gated power systems and film-less image intensifier tubes substantially increase both range and image detail. Active computer enhancement now promises to add normal color patterns to the monochromatic night vision display by comparing the image to a database of daytime scenes.

Resources

• Technical Data from ATN
• Expert Q&A at NightVision Forum