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Appendix 7 - Definitions

Term Definition


The ability of the I2 power source to pulse the voltage in the presence of a bright light source so that vision is not impaired or the I2 tube damaged.

Countermeasures and counter-countermeasures (CM/CCM):

Methods of preventing detection by the enemy or damage to the sensor. In the case of infrared detectors, lasers and protection from lasers are the main form of countermeasures and counter-countermeasures, respectively. Electro-optical (EO) CM/CCM may not be exported under standard FMS cases or DCS export licenses.

Dual-use/commercial systems

Items on the U.S. Commerce Control List (CCL) by the Department of State Commodity Jurisdiction or Government Jurisdiction process. As a general rule, these items are specifically designed or configured as consumer-ready products for use in specific civil applications that have no significant military applicability.

Exception to Policy (ETP)

DTSA approval required when an NVD request is for the first introduction of NVD capability to the country and end-user, capability higher than NVEPIG guidelines, end-users not specified in Section C1.4.7.1., or end-users not meeting the requirements listed in Section C1.4.7.4. The ETP requires a CTA/CCMD concurrence.

Figure of Merit (FoM)

A performance metric of I2 tubes that is calculated by multiplying the signal-to-noise ratio by the resolution as measured in line-pairs per millimeter (lp/mm). Increased FoM roughly corresponds to increased tactical range performance.


Measured in millimeters (mm), it is the limiting diameter of light bloom caused by surrounding bright point sources. Halo is most commonly observed in I2 NVDs when used in an urban warfare environment with city street lights. The light bloom obscures scene content and affects the clarity of image. Smaller halo provides for truer representation of image detail in the presence of bright point sources.

Image fusion

The general category of technology, including, but not limited to software, algorithms, sensors, optical components and other enabling technologies, capable of automatically combining multi-sensor inputs in a manner that results in an output with more information or enhanced quality or task relevance than any individual sensor. Image fusion generally optimizes image quality and militarily relevant scene content without the need for user intervention. Image blending or mixing techniques, which include fixed combinations of intensities independent of scene content, are generally not considered to be image fusion.

Image Intensifier (I2)

Electro-optic systems, equipment, or components capable of detecting and amplifying optical signals or images via electron magnification in the ultraviolet, visible, infrared, x-ray, or gamma ray portions of the electromagnetic spectrum. These low light sensors may be categorized by generational descriptors based on the photocathode material and other characteristics, and may take the form of tube, solid state device, or hybrid.

Infrared (IR)

The part of the invisible electromagnetic spectrum adjacent to the red end of the visible spectrum in the range between 0.7 and 12 microns. Near IR (NIR) is the 0.7 -1.8 micron range, mid wavelength IR (MWIR) the 3-5 micron range, long wavelength IR (LWIR) the 8 -12 micron range, and very long wavelength infrared to 30 microns.


Military applications include pointers seen by NVDs, illuminators to enhance thermal view, range finders to determine distance, and designators to track or illuminate a target. Lasers devices do not require man-portable NVD processing as addressed in this handbook.

Man-portable NVD

For purposes of this handbook, man-portable NVDs refer to devices, both I2 and IR/thermal, which may be worn or small arms weapon mounted, e.g., goggles, weapon sights.

Military Night Vision Device/System

I2, thermal, low light, or other electro optical (EO)/IR systems designed, developed, adapted, modified, or configured for military application and have significant military applicability. These systems enable acquisition, tracking, or monitoring of military scenes or targets at tactically or strategically significant ranges under militarily relevant conditions.

Night Vision

Encompasses thermal imaging, I2, and any other technology that provides vision, imaging, or scene information in any portion of the infrared spectrum.

Night Vision Advisory

A process for NVD approval that ensures responsibility for the release, accountability for the NVD, proper use, and safeguarding of NVD technology when the country has previously received NVDs, and the capabilities are equal to or lower than listed in the NVEPIG. The Advisory requires an SCO endorsement. An Advisory does not require the CTA/CCMD concurrence unless requested. Release approval for advisories is granted unless objections are raised within 10 working days.

Platform-mounted NVD

For purposes of this handbook, platform-mounted NVDs are not man-portable, require an external power supply, or require integration into another system.


Capability of the EO/IR system to orient and point in relation to a target, mitigate platform vibration, and achieve image quality under tactical conditions. Stabilization for military targeting systems establishes the ultimate level of pointing accuracy obtainable by maintaining image "lock" in a dynamic environment characterized by motion, shock, and vibration. It is usually measured and specified in micro radians.

Thermal Imager

A category of imaging sensor that detects heat in the infrared spectrum (1 -12.5 microns). Thermal imagers are used in no light situations and can be divided into two categories: those with cooled infrared focal plane arrays (FPA) and those with uncooled (at or near room temperature) FPAs. Generally, cooled thermal imagers have higher sensitivity, higher performance, are more expensive than uncooled thermal imagers, and used for long range night vision application.