Scopes / Glossary
Automatic Brightness Control: Electronic feature that automatically reduces voltage to the micro-channel plate.Maintains image brightness within optimal margins and protects the tube. The effect can be seen with rapid change in lighting.
Auto-Gated Power Supply:
Systematical turning on and off at a fast rate to reduce blooming effect on night vision devices and thermal optics.
Dirt or other blemish in the image intensifier, possibly between the night vision lenses.
Defects caused by flaws in the micro-channel plate that adversely affect the image displayed by electro optic devices.
Viewing a single image source with both eyes.
Viewing an image through two channels, one per each eye.
Loss of thermal night vision due to overloading of bright light, also known as the halo or white out effect.
Bright Source Protection:
Reduction in voltage to the photo-cathode when the night vision device is exposed to bright light sources.
Alignment of the scope to the bore of the weapon.
Commercial specifications used to define night vision image tube quality, testing and inspection by L3 or SureFire manufacturer.
Irregular pattern of dark lines in the night vision field of view.
Daylight Training Filter:
Glass filter assembly designed to fit over the objective lens of a night vision device filtering light input to a safe level.
Measurement of eye correction or refractive power on a lens adjusted to individual eyesight.
Grainy effect in the night vision device caused by manufacturing flaws in the intensifier tube and fiber optics.
Equivalent Background Illumination:
Amount of light seen through a night vision device when image tube has no light present on the photo-cathode.
Glowing in the perimeter of an image area of night vision device.
Fluctuating pinpoint of bright light in the image area that does not go away when all light is blocked from the objective lens.
Distance between eye and rifle scope to achieve the optimal image.
Width of the terrain image when viewed through a riflescope.
Figure of Merit:
Image intensification calculated by millimeter signal to noise.
Honeycomb pattern throughout the image and inherent in the structure of the micro-channel plate of the night vision rifle scope or monoculars.
Unit of brightness equal to one candle at one foot distance.
The factor by which a night vision device amplifies light input.
Circular region around a bright light that appears brighter due to elastic collisions of electrons on the MCP surface.
Image intensifier protection feature incorporating a sensor, microprocessor and circuit breaker. This feature will turn the system off during periods of extreme bright light conditions.
The adjustment for the space between the two eyepieces of binocular optics to accommodate individual differences.
Built-in infrared diode that emits invisible light providing supplemental illumination in a night vision device.
Illumination below the visible spectrum. It cannot be seen by human eye.
ITAR (International Traffic in Arms Regulations):
US Government regulatory agency controlling the export of defense-related materials, articles, and services on the United States Munitions List.
Electronic light source based on semiconductor diode when forward biased, the electrons recombine with holes releasing energy in the form of light called electro-luminescence.
Light Lens Cover:
Allows marginal amounts of light on to the lens of a night vision device usually for training purposes only.
Photons visible to the human eye in one second.
Single eyepiece optical device.
Stringent and exacting specifications required by the US military
Metal coated glass disk that multiplies the electrons produced by the photo-cathode and eliminates distortion.
One-millionth of a watt, a derived unit of power.
Reticle designed for miliradian unit of measurement and allows hunter to accurately estimate range using a thermal night vision rifle scope or monoculars.
Unit of measurement to determine laser divergence, one unit is equal to 0.001 radian with a deviance of 1-meter per 1000-meters.
Unit of measurement equal to one thousandth of a watt.
Minute Of Angle:
Rifle scope point of reference, 1.047" per 100-yards.
Unit measurement of length, one-billionth of a meter.
Short wavelengths of infrared, nominal 750 to 2500 nanometer.
National Stock Number:
13-digit code for standardized items, such as thermal night vision rifle scopes and thermal optic monoculars and recognized by the US Department of Defense.
Surface input for image intensifier tube which absorbs light energy photons and releases electrical energy electrons resulting in the image.
Measures intensifier tube light conversion and transmits an electronic for amplification.
Picatinny Rail Mount:
Series of ridges with t-shaped cross-sections used as standard attachment method for tactical weapons in the US Military.
Ability of the image intensifier, or night vision rifle scope or thermal optic monocular, to distinguish between objects close together.
Adjustable scope or monocular aiming point inside the optical weapon commonly referred to as the "crosshairs".
Measurement of the light signal reaching the eye divided by the measured extraneous light.
Random sparkling effect throughout the scope or monocular image area such as scintillation of the micro-channel plate image intensifier.
Image tube output that produces the image for viewing.
Stereoscopic Night Vision:
Multiple view image produced by one device that represent both the left and right eye viewpoint.
Equal to tube gain minus losses induced by system components such as lenses, laser splitting and filtration.
Variable Gain Control:
Manually adjusting the gain in varying light conditions, an L3 feature in the thermal optic monoculars and night vision rifle scopes.
Derived unit of power measuring energy conversion in International System of Units, 1-watt is equal to 1-joule of energy, per second.
Weaver Mounting System:
US weapon mounting system used for attaching sighting devices to weapons.
Method of adjusting crosshairs to compensate for projectile characteristics at known distances.