Early Attempts at Night Vision Technology
Historically, military tacticians have benefitted from the ability to maneuver under the cover of darkness. However, military maneuvers were rarely conducted at night because it was so risky.
During WWII, the United States, Britain, and Germany developed a rudimentary infrared sniper scope that used near-infrared cathodes coupled to visible phosphors to provide a near-infrared image converter to begin night fighting efforts. Though approximately 300 of these Sniperscopes were shipped across the Pacific in 1945, few were used. With a range of less than 100 yards, they could only provide perimeter defense. These limited range, rifle-mounted scopes ran off of cumbersome batteries and required active IR searchlights so large that they had to be mounted on flatbed trucks. This searchlight could readily be detected by enemy soldiers with similar equipment.
Despite its inadequacies, this infrared Sniperscope initiated investigation into advanced night vision technology. Military leaders saw many uses for such technology beyond sniping under the cover of darkness. There was potential for night vision goggles, helmets, and weapon sights to equip armies to operate 24 hours a day. The next challenge in night vision technology would be developing passive systems without IR searchlights, that would no longer betray a soldier’s position to the enemy.
Establishing the Night Vision and Electronic Sensors Directorate (NVESD)
The Night Vision and Electronic Sensors Directorate (Night Vision) dates back to 1954 with the founding of the Research and Photometric Section of the Corps of Engineers Engineering Research and Development Laboratories (ERDL). ERDL began with minimal funding and without laboratory facilities. The Research and Photometric Section began developing personalized night vision equipment intended for use by individual soldiers in the field, which carved a unique niche for ERDL: many similar organizations were developing large weapons systems.
The initial mission of Night Vision was “the Conquest of Darkness so that the individual can observe, move fight, and work at night by using an image that he can interpret without specialist training and to which he can immediately respond”. As Night Vision expanded into new areas and across Army platforms, this objective expanded to discover new applications for its sensor technology.
Early Areas of Night Vision Research and Accompanying Challenges
The 1940s and 1950s
Through the 1940s and 1950s, Night Vision focused on improving the cascade image tube, developed in Germany during WWII. Night Vision contracted scientists from the Radio Corporation of America (RCA) to research and develop a near-infrared, two-stage cascading image tube. This new cascade image tube, which used a multi-alkali photocathode, exceeded expectations. The Image Intensification (I2) system collected and intensified ambient light from the night sky. Night Vision began improving the system, which, while innovative, presented challenges limited light gain and inverted images. To remedy these issues, a third electrostatic stage was added to enhance light gain and to re-invert the image. With this, however, the tube grew to 17inches in length and 3.5inches in diameter; too large for practical applications.
From 1957-1958, John Johnson, a Night Vision scientist, worked to develop methods of predicting target detection, orientation, recognition, and identification. Johnson worked with volunteer observers to test each individual's ability to identify targets through image intensifier equipment under various conditions. Thus, the 1950s also marked a noted development in the performance modeling of night vision imaging systems.
In October of 1958, at the first Night Vision Image Intensifier Symposium, Johnson presented his findings in a paper entitled, “Analysis of Image Forming Systems”. The paper described image and frequency domain approaches to analyzing the ability of observers to perform visual tasks using I2. The findings presented became known as the Johnson Criteria and proved to be hugely important in understanding the performance of and guiding further development of night vision devices and systems.
Examples of night vision technology fielded in the 1940's and 1950's include:
1940s - Sniperscope
1940s - Metascope
1955 - First NIR Mapper
1958 - First IR Linescanner
During the mid-1960s, Night Vision scientists and engineers fielded the first generation of passive night vision devices for U.S. troops, including a Small Starlight Scope. These systems were referred to as the First Generation Image Intensifiers. Second and third generations have since evolved.
Also during this decade, to pursue Research and Development (R&D) objectives, Night Vision worked and contracted with scientists and engineers from other organizations. Night Vision advanced beyond acting solely as a research institution to coordinating and managing further shared research initiatives in many fields including astronomy, nuclear physics, and radiology and continued to work with research personnel from leading commercial organizations. This collaboration with private industry became one of Night Vision’s fundamental strategies in technology development.
The First Generation Small Starlight Scope was soon used in the field. As the United States became increasingly involved in the Vietnam War, U.S. soldiers recognized that the enemy relied on the cover of darkness to conceal its offensive operations. In 1964, the U.S. Army issued night vision equipment to its deployed troops: The War became a driving force in further technology development.
Personnel from Night Vision traveled to Vietnam to evaluate fielded equipment and interviewed U.S. soldiers and Vietnam veterans to collect user feedback. Gaining real-time, first-hand knowledge from Warfighters became a hallmark of Night Vision’s R&D technique and was later especially useful in assessing soldiers’ needs during Operation Desert Storm. Regarding this approach, Dr. Robert Wiseman, former head of Night Vision noted soldier reports that, “You don’t know how many lives you’ve saved.”
On November 2, 1965, the Night Vision Laboratory (NVL), the precursor of Night Vision and Electronic Sensors Directorate (NVESD), was established to consolidate the several areas of night vision research under a single organizational director, Dr. Robert S. Wiseman. The areas of research for which NVESD was then officially responsible were Visionics & Image Intensification, Far-Infrared, Light Source, Thin Film, Advanced Developments, Systems Development, and Systems Evaluation.
Subsequent to this unification, there was an R&D organization on Fort Belvoir dedicated to studying night vision technology. NVL expanded its R&D efforts and began to make new discoveries in various fields, including lasers and battlefield sensors. It took on the ‘official’ name of Night Vision and Electronic Sensors Directorate (NVESD) to better encompass all areas of research.
Night vision equipment fielded in the 1960s included:
1964 – Starlight Scope
1965 – TVS-4 Night Observation Device
1967 – Low Light Level Television; Pulse Gated I2-TVS-2 Crew Served Weapon Night Sight
1969 – First Laser Rangefinder (Ruby); PSS-11 Handheld Metallic Mine Detector
Thermal imaging, based on the far infrared spectrum, forms an image of objects by sensing the differences between heat radiated by an object or target and its surrounding environment. Before the 1970s, prototypes using this technology were very expensive.
While Night Vision R&D focused much of its effort on developing practical night vision equipment based on near-infrared technology, scientists also worked toward technological advancements that would pave the way to far-infrared night vision equipment. The advent of linear scanning imagers, consisting of multiple-element detector arrays, led Night Vision to develop thermal imaging systems in the 1970s. Multiple-element arrays provided a high-performance, real-time framing imager that could be practically applied to military use. This technology led to targeting and navigation systems known as Forward Looking Infrared Systems (FLIR). FLIR Systems provide the advantage of ‘seeing’ at night as well as through smoke, fog, and other obscuring conditions.
FLIR imaging was in high demand for all weapons system platforms, which spurred a proliferation of designs and prototypes for multiple platforms. To satisfy this demand, a group of experts from Night Vision designed a Universal Viewer for Far Infrared in 1973 that led to the family of Common Modules fielded by thousands across multiple platforms. The Common Module-based FLIR systems were less expensive to purchase and produce than previous designs.
In 1978, the Optical Radiation Technical Area, a group of laser scientists and engineers moved from Fort Monmouth, NJ to the Night Vision Laboratory in Fort Belvoir, VA. At Fort Belvoir, they designed and fabricated some of the first monolithic linear laser diode arrays for operation at room temperature for high peak power laser illuminators. They developed a complete pulsed laser system that operated at 500 watts per pulse at 15 KHz. This compact laser imaged targets up to 3 km away.
Night Vision’s laser efforts expanded to include solid state laser R&D, gas lasers, laser radar, chemical detection, lager rangefinder systems, light aiming systems, and laser designator systems. Later, the laser team began working on diode pumped lasers for Army applications. Considerable effort was devoted to tunable lasers for optical countermeasures using various solid state laser materials and nonlinear frequency conversion techniques.
Night vision accomplishments in the 1970's include:
1971 - Handheld Thermal Viewer; FLIR Production; PRS-7 Handheld Non-Metallic Mine Detector
1975 - PVS-4 Individual Weapon Sight; Night Vision Thermal Model Publication
1976 - Common Module FLIR Production
1977 - PVS-5 Night Vision Goggles
In the 1980s Night Vision began improving its Image Intensification systems. The third generation of night vision based on image intensification technology, composed of the AN/AVS-6 Aviators Night Vision Imaging System (ANVIS) and the AN/PVS-7 Night Vision Goggles, was fielded.
In 1980, NVESD developed the AN/GVS-5 Laser Infrared Observation Set, which significantly increased the probability of hitting stationary or airborne targets with the first round fired. Fielded in 1988, the AN/AAS-32 Airborne Laser Tracker greatly improved the offensive capability of Army helicopters.
Night Vision also developed Generation II FLIR by improving its thermal imaging technology. Improved sensor resolution and sensitivity coupled with reduced exposure time through signal processing for aided target detection and recognition led to Generation II FLIR with greater stand-off range.
Also in the 1980s, Night Vision pioneered the revolution in aided target recognition. While U.S. forces now had the ability to see in the dark, improvements were still necessary to help soldiers distinguish between friend and enemy. By uniting with private industry scientists, Night Vision helped develop algorithms that were more effective at detecting targets and minimized false alarm confusion.
Accomplishments during the 1980s:
1981 - VGS-2 Tank Thermal Sight
1982 - TAS-6 Night Observation Device, Long Range
1984 - AVS-6 ANVIS Goggles, 3rd Gen I2
1986 - GVS-5 Laser Rangefinder
1987 - PVS-7 Night Vision Goggles
1988 - AAS-32 Airborne Laser Tracker
In the 1990s, Night Vision developed an eyesafe laser rangefinder, the AN/PVS-6 Mini Eyesafe Laser Infrared Observation Set (MELIOS). The 1990s also saw the next generation of Aviators Night Vision Imaging System with Heads-Up Display (AN/AVS-7) and an improved group of lightweight thermal weapon sights for ground troops.
During the 1990s, Night Vision pioneered the concept for Horizontal Technology Integration (HTI), a new method of developing and acquiring equipment for the U.S. Army. This system focused on developing equipment that integrates FLIR subsystems from a single Project Manager across several weapon systems. This use of common hardware reduced equipment procurement costs.
The major test of Night Vision’s technological efforts came in late 1990/early 1991 when Iraqi armed forces invaded Kuwait. The United States and its allies immediately mobilized to force Saddam Hussein’s troops out of Kuwait during Operation Desert Storm. Night Vision systems proved vital to operating in the desert environment. As General Barry McCaffrey, then commander of the 24th Infantry Division, testified: “Our night vision capability provided the single greatest mismatch of the war.”
Night Vision systems using I2 and FLIR technologies were used by ground troops on major weapons systems including tanks, helicopters, missile systems, and infantry fighting vehicles. Targeting systems equipped with FLIR technology that could ‘see through’ dense smoke, dust, fog, and haze at great distances were crucial to the major weapon systems as in Vietnam, Operation Desert Storm showed Night Vision scientists and engineers a way to improve technology by integrating I2 and FLIR capabilities.
Laser Research in the 1990s
In the 1990s, work continued on compact solid state lasers, multifunction lasers, chemical and biological agent detection, and laser radar. Laser system development was also pursued with Night Vision on rangefinders, designators, and laser radar for target identification and obstacle avoidance.
Uncooled IR Sensors for Military Applications
Continuing in its tradition of cooperative R&D, Night Vision works with nongovernment companies to develop uncooled IR sensors and uncooled focal plane arrays sufficient for rifle sights, crew served weapons, driving aids and missile seekers have been demonstrated. This technology has also been transitioned to engineering development and production programs. Looking to the future, uncooled technology should lead to exciting new concepts, to include IR goggles and low cost missile seekers. Networked arrays of miniature, low-cost, light-weight, low-power IR sensors provide exciting new possibilities for sensors to support the Army’s vision by providing situational awareness. Larger arrays of uncooled imaging systems offer affordable integration of sensors on robotic, air, and ground platforms.
By the end of the 20th century, NVESD had provided the Army the legacy to “Own the Night”. NVESD has transitioned the unique sensor technologies that have resulted in fielding over 400,000 Image Intensifier Systems; 60,000 Thermal Systems; 40,000 Laser Systems; and 15,000 Countermine systems.
RDECOM CERDEC NVESD is strongly focused on the Army Vision for the Transformation of the Current to the Future Force. In order to provide the technology transition resulting in superior tactical sensors for tomorrow’s Warfighter, Night Vision’s mission is to:
- Conduct Research and Development to Provide US Land Forces with Advanced Sensor Technology to dominate the 21st Century Digital Battlefield;
- Acquire and Target Enemy Forces in Battlefield Environments;
- Detect and Neutralize Mines, Minefields, and Unexploded Ordnance; Develop Humanitarian Demining Technology;
- Deny Enemy Surveillance & Acquisition through Electro-Optic, Camouflage, Concealment, and Deception Techniques;
- Provide for Night Driving and Pilotage; and
- Protect Forward Troops, Fixed Installations and Rear Echelons from Enemy Intrusion.