Glossary of Thermal Imaging, Military, and Night Vision Terminology
Navigating the intricate world of thermal imaging, military operations, and night vision can be daunting, especially with the myriad of technical jargon and acronyms. This glossary serves as a comprehensive guide, elucidating complex terms and providing clarity to enthusiasts, professionals, and novices alike. From understanding the nuances of infrared radiation in thermal imaging to deciphering military strategies and grasping the mechanics of night vision technology, this resource aims to demystify the language and foster a deeper appreciation for the advancements in these fields. Whether you’re a seasoned expert or just starting your journey, this glossary is an invaluable tool to enhance your knowledge and comprehension.
ABF (Auto Back Focus)
Thermal Imaging Terminology
Auto Back Focus (ABF) is an advanced feature found in many modern imaging devices, including cameras, camcorders, and security cameras. It is designed to improve the precision and efficiency of adjusting the focus on the camera’s lens.
Absolute Temperature
Thermal Imaging Terminology
The temperature of an object measured in Kelvin (K) or Rankine (°R), where 0 K or 0 °R represents absolute zero, the lowest possible temperature.
Absorption
Thermal Imaging Terminology
The process by which materials absorb thermal radiation, converting it into heat energy.
Acoustic Signature
Military Terminology
A combination of acoustic emissions of sound waves by all sources, including auxiliaries, onboard a ship or a submarine.
Active Illumination
Thermal Imaging Terminology
A method of imaging where the imaging device provides its own light source.
Active Infrared Thermography
Thermal Imaging Terminology
Active Infrared Thermography (IRT), also known as Active Thermography or Active Infrared Testing (AIT), is a non-destructive testing (NDT) technique used to detect defects, anomalies, or temperature variations in materials and structures.
Active Sonar
Military Terminology
A type of sonar that emits an acoustic signal or pulse of sound into the water. If an object is in the path of the sound pulse, the sound bounces off the object and returns an “echo” to the sonar transducer.
Aerial Refueling:
Military Terminology
Also known as air refueling, in-flight refueling (IFR), and tanking, is the process of transferring aviation fuel from one military aircraft (the tanker) to another (the receiver) during flight.
Aerostat
A lighter than air aircraft that gains its lift through the use of a buoyant gas. Aerostats include unpowered balloons and powered airships.
Airborne Early Warning (AEW):
The use of aircraft to detect enemy aircraft or ships at a long range so that defenses can be alerted as early as possible.
Air Intercept (AI):
A type of radar system designed to guide a fighter aircraft toward an enemy aircraft.
Air-to-Air Missile (AAM):
A missile fired from an aircraft for the purpose of destroying another aircraft. AAMs are typically powered by one or more rocket motors, usually solid fueled but sometimes liquid fueled.
Air-to-Surface Missile (ASM):
A missile designed to be launched from military aircraft (bombers, attack aircraft, fighter aircraft) and strike ground targets on land, at sea, or both.
Alpha Blending
Alpha blending is a digital image processing technique used to combine multiple images or layers, creating a smooth and translucent effect.
Amphibious Warfare:
A type of offensive military operation that today uses naval ships to project ground and air power onto a hostile or potentially hostile shore at a designated landing beach.
Anti-Ship Missile (AShM):
A guided missile that is designed for use against ships and large boats.
Anti-Submarine Warfare (ASW):
Various branches of a nation’s military have responsibility for the detection and destruction of enemy submarines.
Anti-Tank Warfare:
Any method of defeating a tank in combat.
Apparent temperature, also known as “feels-like” temperature, is a concept used in thermal imaging and weather forecasting to describe how the combination of temperature, humidity, and wind speed affects the human perception of the weather.
Aperture:
The opening in a lens through which light passes to enter the camera.
Armored Warfare:
The use of armored fighting vehicles in modern warfare.
Artificial Intelligence
By integrating AI algorithms and machine learning techniques, these imaging technologies and military systems have achieved new levels of sophistication, accuracy, and adaptability.
Artillery:
Large-caliber guns used in warfare on land.
Assault Rifle:
A rapid-fire, magazine-fed automatic rifle designed for infantry use.
Attack Submarine:
Also known as a hunter-killer submarine, is a submarine specifically designed for the purpose of attacking and sinking other submarines, surface combatants, and merchant vessels.
Anti-UAV Defence System (AUDS) is a counter-drone technology designed to detect, track, and neutralize unmanned aerial vehicles (UAVs) to protect airspace from potential threats.
Autocannon:
A type of large-caliber automatic firearm that fires shells as opposed to bullets.
Automatic Rifle:
A type of self-loading rifle that is capable of automatic fire.
Autofocus:
A feature of some optical systems that allows them to focus on a subject automatically.
Background Radiation
The natural thermal radiation emitted by the environment, including objects and surfaces, that can affect thermal imaging and night vision measurements.
Ballistic Missile:
A missile that follows a ballistic trajectory with the objective of delivering one or more warheads to a predetermined target.
Ballistic Missile Submarine:
A submarine capable of deploying submarine-launched ballistic missiles (SLBMs) with nuclear warheads.
Bandwidth
In the context of thermal imaging and night vision systems, bandwidth refers to the range of wavelengths or frequencies of radiation that the equipment can detect and process.
Battleship:
A large armored warship with a main battery consisting of large caliber guns.
Beam Divergence:
Beam divergence is a phenomenon that occurs when an infrared or laser beam spreads out over distance due to diffraction.
Biocular:
An optical device that presents an image to both eyes, but uses a single objective lens.
Blackbody
A theoretical object or reference source that emits thermal radiation based on its temperature. It is used to calibrate and validate thermal imaging devices.
Bolometer
A type of thermal sensor used in some infrared cameras to detect and measure thermal radiation.
Bomber:
A combat aircraft designed to attack ground and naval targets by dropping air-to-ground weaponry (such as bombs), launching torpedoes, or deploying air-launched cruise missiles.
Boresight
The process of aligning the line of sight of a thermal imaging or night vision device with the bore axis of a weapon or optical system.
Bi-ocular:
A type of night vision device that uses two eyepieces to provide depth perception and a more immersive viewing experience.
Brightness Gain:
The measure of the increase in image brightness achieved by the night vision device’s intensifier tube.
CATS (Computer-Aided Test System):
A software or hardware system that aids in the analysis, interpretation, and storage of data acquired from thermal imaging or night vision tests.
CCD (Charge-Coupled Device):
A sensor for recording images, used in digital cameras and camcorders.
CMOS (Complementary Metal-Oxide-Semiconductor):
A technology used for constructing integrated circuits, including image sensors in digital cameras.
Carrier Battle Group:
A naval fleet consisting of an aircraft carrier (designated the capital ship) and its large number of escorts, together defining the group.
Close-In Weapon System (CIWS):
A point-defense weapon system for detecting and destroying short-range incoming missiles and enemy aircraft which have penetrated the outer defenses, typically mounted shipboard in a naval capacity.
Coastal Artillery:
Warships and submarines of the coastal defense forces and naval infantry, often stationed in coastal artillery forts, coastal batteries, and coastal defense batteries.
Collimator:
A device that narrows a beam of particles or waves.
Combat Vehicle:
A type of self-propelled, weaponized military vehicle used for combat operations.
Cruise Missile:
A guided missile used against terrestrial targets, that remains in the atmosphere and flies the major portion of its flight path at approximately constant speed.
Diopter:
A unit of measurement of the optical power of a lens or curved mirror.
Destroyer:
A fast, maneuverable, long-endurance warship intended to escort larger vessels in a fleet, convoy, or battle group and defend them against smaller, short-range attackers.
Drone:
An unmanned aircraft or ship guided by remote control or onboard computers.
DRI in the context of thermal imaging refers to “Detection, Recognition, and Identification.” It is a standard set of criteria used to evaluate the performance of thermal imaging systems, especially in military and security applications.
Electronic Warfare (EW):
Any action involving the use of the electromagnetic spectrum or directed energy to control the spectrum, attack an enemy, or impede enemy assaults.
EMCCD (Electron-Multiplying CCD):
A CCD device that amplifies the signal before it is read out to reduce read noise.
Field of View:
The extent of the observable world that is seen at any given moment.
Fighter Aircraft:
A military aircraft designed primarily for air-to-air combat against other aircraft, as opposed to bombers and attack aircraft, whose main mission is to attack ground targets.
Forward Looking Infrared (FLIR) is a thermal imaging technology that detects infrared radiation (heat) to create images, allowing for visibility in low-light or obscured conditions.
Focal Length:
The distance between the center of a lens and its focus.
Focal Plane:
The plane, perpendicular to the optical axis, in which light rays from a subject at infinity come to a focus.
A full-color night vision system is a technological advancement over traditional green-hued night vision optics. Unlike the monochromatic green or black-and-white imagery produced by conventional night vision goggles, full-color night vision provides images with true-to-life colors, even in extremely low-light conditions.
Geospatial Intelligence:
The exploitation and analysis of imagery and geospatial information to describe, assess, and visually depict physical features and geographically referenced activities on the Earth.
Guided Missile Destroyer:
A destroyer designed to launch guided missiles.
Gunship:
A military aircraft armed with heavy guns, primarily intended for ground attack.
Heavy Bomber:
A bomber aircraft capable of carrying the largest payload of air-to-ground weaponry (usually bombs) and longest range of their era.
Helicopter Gunship:
A military helicopter with the primary role of an attack aircraft, with the capability of engaging targets on the ground, such as enemy infantry and armored vehicles.
Image Intensifier:
A device that amplifies low light-level images to levels that can be comfortably observed.
Infantry Fighting Vehicle (IFV):
A type of armored fighting vehicle used to carry infantry into battle and provide direct-fire support.
Infrared (IR):
A type of electromagnetic radiation with wavelengths longer than those of visible light but shorter than those of radio waves.
Intercontinental Ballistic Missile (ICBM):
A guided ballistic missile with a minimum range of 5,500 kilometers primarily designed for nuclear weapons delivery.
Interceptor Aircraft:
A type of fighter aircraft designed specifically to prevent successful missions of enemy aircraft, particularly bombers and reconnaissance aircraft.
Jet Fighter:
A jet engine powered fighter aircraft.
Lidar (Light Detection and Ranging):
A remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth.
LWIR
Long-Wave Infrared (LWIR) is a crucial segment within the electromagnetic spectrum utilized extensively in thermal imaging technology.
Microbolometer:
A specific type of bolometer used as a detector in a thermal camera.
Mine-Resistant Ambush Protected (MRAP):
A term for United States military light tactical vehicles produced as part of the MRAP program that are designed specifically to withstand improvised explosive device (IED) attacks and ambushes.
MRTD (Minimum Resolvable Temperature Difference):
A measure of a thermal imaging system’s sensitivity, representing the smallest temperature difference that the system can detect and distinguish as separate points.
Multi-Mode
Refers to thermal imaging or night vision devices that offer multiple operating modes, such as thermal, night vision, or visible light.
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Multispectral Imaging:
Capturing image data within specific wavelength ranges across the electromagnetic spectrum.
MWIR
The mid-infrared spectral band that ranges from approximately 3 to 5 micrometers in wavelength, commonly used in thermal imaging applications.
MWIRFP (Mid-Wave Infrared Focal Plane)
The area in an infrared camera where the infrared radiation is focused to form an image in the mid-wave infrared spectrum.
Optical Axis:
The line passing through the center of the lens in an optical device.
Optical Zoom:
The change of the focal length of a lens, which changes the field of view and magnifies the image.
Passive Illumination:
A method of imaging where the imaging device does not provide its own light source and relies on ambient light.
Pixel:
The smallest controllable element of a picture represented on a screen.
Polarization:
The property of waves that oscillate with more than one orientation.
Radiometry:
The science of measuring electromagnetic radiation, including light.
Resolution:
The smallest interval measurable by a scientific (especially optical) instrument; the resolving power.
Reticle:
A series of fine lines or fibers in the eyepiece of an optical device, such as a telescope or microscope, or on the screen of an oscilloscope, used as a measuring scale or an aid in locating objects.
Saturation:
The intensity of a color, expressed as the degree to which it differs from white.
Signal-to-Noise Ratio (SNR):
A measure used in science and engineering that compares the level of a desired signal to the level of background noise.
Spectrometer:
An apparatus used for recording and measuring spectra, especially as a method of analysis.
Stereoscopic Vision:
The ability to perceive depth and 3-dimensional structure obtained on the basis of visual information deriving from two eyes by individuals with normally developed binocular vision.
Thermography:
The use of a thermal imager or infrared camera to “see” thermal energy emitted from an object.
Ultraviolet (UV):
A type of electromagnetic radiation with wavelengths shorter than visible light but longer than X-rays.
Uncooled Detector:
A type of thermal imaging device that operates at room temperature.
Wavefront:
A surface over which a wave has a constant phase; in particular, the surface of the wave at a particular time.
Wavelength:
The distance between successive crests of a wave, especially points in a sound wave or electromagnetic wave.
White Hot/White Hot Mode:
In thermal imaging, the white hot mode is a color palette used to display thermal images. It represents colder temperatures in white and hotter temperatures in black. This mode is commonly used in night vision and surveillance applications.
Wide-Area Surveillance:
Wide-area surveillance involves using thermal imaging systems with a broad field of view to monitor large geographical areas. This approach is often employed in military reconnaissance, border security, and other surveillance operations.
Waveband:
Waveband refers to a specific range of electromagnetic wavelengths that thermal imaging sensors can detect. Different wavebands may be used for various applications, such as mid-wave infrared (MWIR) or long-wave infrared (LWIR) for different thermal imaging requirements.
Wide Dynamic Range (WDR):
Wide dynamic range is a feature in thermal imaging systems that enables the camera to capture details in both very bright and very dark areas of the scene. It helps prevent overexposure and underexposure, ensuring a clear image with balanced contrast.
Warm-Up Time:
Warm-up time refers to the duration it takes for a thermal imaging system to reach its optimal operating temperature. During this period, the system stabilizes, ensuring accurate thermal readings and improved image quality.
Wide FOV (Field of View):
The field of view is the area that a thermal imaging camera can capture at a given distance. A wide FOV allows for greater coverage, making it suitable for surveying large areas during military reconnaissance or surveillance missions.
Wavefront Error:
Wavefront error refers to the distortion in the wavefront of infrared radiation detected by a thermal imaging sensor. Minimizing wavefront error is crucial for obtaining accurate and detailed thermal images.
Weapon Target Assignment:
Thermal imaging systems play a vital role in military operations by assisting soldiers in identifying and assigning targets during reconnaissance and combat missions.
Windage Adjustment:
Windage adjustment is the process of aligning the thermal sight with the firearm to compensate for wind drift and ensure precise aiming and shooting.
Wideband Spectral Imaging:
Wideband spectral imaging involves capturing and processing infrared radiation across a broad range of wavelengths. This technique provides detailed spectral information and is used in advanced thermal imaging applications.
Weight Reduction:
Weight reduction is a critical factor in the design of thermal imaging equipment, especially for military personnel who carry the devices during missions. Lighter thermal systems enhance mobility and reduce fatigue.
Wide Temperature Range:
Thermal imaging systems with a wide temperature range can accurately detect and analyze objects with different thermal signatures, from extremely cold to hot temperatures.
Wide-Angle Lens:
A wide-angle lens in thermal imaging cameras provides a broader field of view, allowing operators to survey more extensive areas without compromising image quality.
Weapon Integration:
Weapon integration involves seamlessly integrating thermal imaging capabilities into various military weapons and platforms, enabling enhanced target acquisition and engagement.
Wide Spectral Response:
Wide spectral response in thermal imaging sensors allows them to capture a broad range of infrared wavelengths, expanding their application capabilities in different environments and scenarios.
Weapon-Mounted Surveillance System:
Weapon-mounted surveillance systems combine thermal imaging and other sensors on military firearms, providing soldiers with enhanced situational awareness and target identification capabilities.
Wideband Polarization:
Wideband polarization involves using polarized thermal imaging to analyze the polarization state of infrared radiation. This technique enhances target detection and discrimination.
Weapon Fire Control System:
A weapon fire control system equipped with thermal imaging assists in precisely aiming and engaging targets, enhancing overall accuracy and effectiveness.
Windowing:
Windowing is a technique used in thermal imaging to focus on specific regions of interest within the scene, allowing for detailed examination and analysis of critical areas.
Wide Dynamic Range Imaging:
Wide dynamic range imaging in thermal cameras enables them to capture scenes with a broad range of temperature differences, providing better contrast and detail in challenging lighting conditions.
Wavelength Filters:
Wavelength filters are used in thermal imaging systems to limit the range of infrared radiation detected, allowing for targeted analysis of specific thermal signatures.
X-Axis Alignment:
X-axis alignment involves adjusting the horizontal alignment of thermal imaging devices to ensure that they accurately capture and display thermal images in the correct orientation.
X-Connector:
An X-connector is a type of thermal imaging accessory used to join or split thermal imaging cables for connecting various components in a thermal imaging system.
X-Focal Length:
X-focal length refers to the horizontal distance between the thermal imaging lens and the sensor. Properly adjusting the X-focal length ensures sharp focus and optimal image quality.
X-Band Radar:
X-band radar is a type of radar that operates in the microwave frequency range. It can complement thermal imaging systems by providing additional information about the position and movement of targets.
X-Ray Absorption:
X-ray absorption is the process by which X-rays are absorbed by various materials. In thermal imaging, this process can affect the ability to detect or identify objects behind certain materials.
X-Ray Contrast:
X-ray contrast refers to the ability of thermal imaging systems to differentiate between different materials based on their thermal properties, providing valuable information for detecting concealed objects or identifying potential threats.
X-Spectral Range:
X-spectral range refers to the specific range of wavelengths within the electromagnetic spectrum that a thermal imaging sensor can detect and analyze.
X-Y Coordinates:
In thermal imaging, X-Y coordinates represent the location of a specific thermal signature or target within the field of view, aiding in target tracking and data analysis.
X-XGA Resolution:
XGA resolution is a standard display resolution of 1024 x 768 pixels. Some thermal imaging cameras offer XGA resolution displays, allowing operators to view detailed thermal images with high clarity.
Yaw Stabilization:
Yaw stabilization is a feature in some long-range thermal imaging systems that compensates for rotational movements and vibrations, maintaining a stable view of the target or scene during surveillance or reconnaissance.
Yellow Alarm:
A yellow alarm is a warning signal or indicator in thermal imaging systems that alerts the operator to potential hazards or critical situations based on predefined temperature thresholds.
YAG Crystal Frequency Doubling:
YAG crystal frequency doubling is a process used to generate shorter wavelengths from longer infrared wavelengths, enabling more precise imaging and analysis in specific applications.
Yoke Focus Mechanism:
A yoke focus mechanism is a type of lens focusing system used in some thermal imaging cameras. It enables precise and smooth adjustments to achieve the desired focus on the target or scene.
Yttrium-Aluminum-Garnet (YAG) Laser:
A Yttrium-Aluminum-Garnet (YAG) laser is used in some thermal imaging applications to generate pulsed laser light for specific tasks, such as target illumination or distance measurement.
Yttrium Iron Garnet (YIG) Crystal:
Yttrium Iron Garnet (YIG) crystal is a material used in certain thermal imaging systems as a tunable filter for specific wavelengths. It allows precise selection and control of infrared radiation, improving spectral imaging capabilities.
YUV422 Video Format:
YUV422 is a video format used in some thermal imaging cameras, providing high-quality color representation and efficient video compression for data storage and transmission.
Y-Zone Focusing:
Zone focusing is a technique used in thermal imaging cameras to pre-focus the lens at specific distances or zones. This approach enables quicker target acquisition when switching between different focus points.
Z-Wave:
Z-Wave is a wireless communication protocol used in some thermal imaging devices for remote control and data transmission. It allows for seamless integration and interoperability with other smart devices.
Zirconium Coating:
Zirconium coating is applied to certain thermal imaging components to enhance their durability and resistance to wear, corrosion, and high temperatures.
Zirconium Oxide (ZrO2) Window:
Zirconium oxide is a material commonly used in the construction of thermal imaging windows. It offers high thermal conductivity and transmits infrared radiation effectively, making it suitable for high-performance thermal imaging systems.
Zone Plate Array:
A zone plate array is an optical component used in some thermal imaging systems to diffract infrared radiation. It can improve image quality and resolution by focusing and manipulating infrared light.
Zoom Lens:
A zoom lens in thermal imaging allows users to adjust the focal length and magnification level, enabling them to observe and analyze distant targets more closely. This feature is particularly useful in long-range surveillance and reconnaissance.
Zoom Sensitivity:
Zoom sensitivity refers to how smoothly and accurately a thermal imaging system can transition between different levels of magnification in its zoom lens.
Zero-Point Calibration:
Zero-point calibration involves setting the reference temperature for the thermal imaging system to zero degrees Celsius (0°C) to ensure accurate temperature measurements relative to this reference.
Zero Noise:
Zero noise indicates the absence of electronic noise in thermal imaging systems. Reducing noise ensures clearer thermal images and improved detection of subtle temperature variations.
Zirconium:
Zirconium is a chemical element used in certain thermal imaging components and coatings due to its high melting point and resistance to corrosion and heat.
Z-Wavelength:
Z-wavelength refers to the specific wavelength of infrared radiation detected by thermal imaging sensors in the long-wave infrared (LWIR) spectrum.
Z-NET:
Z-NET is a networking technology used in some thermal imaging systems to enable communication between multiple devices and components in a networked environment.