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SPRITE Infrared Detector
The SPRITE infrared detector is named after the process of signal integration carried out by "Signal Processing In The Element". The technique was invented at the Royal Signals and Radar Establishment at Malvern by a team of scientists including Tom Elliott.Editor worked with Tom Elliot at RRE Malvern The detector allows the build up of detected infrared signal in a mercury cadmium telluride (MCT) photoconductor strip, on a sapphire substrate, by applying a bias current through the strip. The detector is used in a scanned thermal imager and the bias voltage is adjusted to force electrons produced by the detected energy at one end of the strip to drift to the far end of the strip in time with the rate of the scanning such that energy from the same response is built up along the full length of the strip. This allows a much simpler way of integrating responses than linking separate detector cells. This type of detector was used in a series of thermal imagers known as TICM ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Signals And Radar Establishment
The Royal Signals and Radar Establishment (RSRE) was a scientific research establishment within the Ministry of Defence (MoD) of the United Kingdom. It was located primarily at Malvern in Worcestershire, England. The RSRE motto was ''Ubique Sentio'' (Latin for "I sense everywhere"). History RSRE was formed in 1976 by an amalgamation of previous research organizations; these included the Royal Radar Establishment (RRE), itself derived from the World War II-era Telecommunications Research Establishment, the Signals Research and Development Establishment (SRDE) in Christchruch, Dorset, and the Services Electronic Research Laboratory (SERL) at Baldock. Beginning in 1979, the SRDE and SERL moved to Malvern to join the RRE's location.EdsRobert Budand Philip Gummett, ''Cold War Hot Science: Applied Research in Britain's Defence Laboratories 1945-1990'', Harwood, 1999 There were several out-stations in Worcestershire, including the ex- RAF airfields at Defford and Persh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malvern, Worcestershire
Malvern is a spa town and civil parish in Worcestershire, England. It lies at the foot of the Malvern Hills, a designated Area of Outstanding Natural Beauty. The centre of Malvern, Great Malvern, is a historic conservation area, which grew dramatically in Victorian times due to the natural mineral water springs in the vicinity, including Malvern Water. At the 2011 census it had a population of 29,626. It includes Great Malvern on the steep eastern flank of the Malvern Hills, as well as the former independent urban district of Malvern Link. Many of the major suburbs and settlements that comprise the town are separated by large tracts of open common land and fields, and together with smaller civil parishes adjoining the town's boundaries and the hills, the built up area is often referred to collectively as The Malverns. Archaeological evidence suggests that Bronze Age people had settled in the area around 1000 BC, although it is not known whether these settlements were perman ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury Cadmium Telluride
Hg1−xCdxTe or mercury cadmium telluride (also cadmium mercury telluride, MCT, MerCad Telluride, MerCadTel, MerCaT or CMT) is a chemical compound of cadmium telluride (CdTe) and mercury telluride (HgTe) with a tunable bandgap spanning the shortwave infrared to the very long wave infrared regions. The amount of cadmium (Cd) in the alloy can be chosen so as to tune the optical absorption of the material to the desired infrared wavelength. CdTe is a semiconductor with a bandgap of approximately 1.5 electronvolts (eV) at room temperature. HgTe is a semimetal, which means that its bandgap energy is zero. Mixing these two substances allows one to obtain any bandgap between 0 and 1.5 eV. Properties Physical Hg1−xCdxTe has a zincblende structure with two interpenetrating face-centered cubic lattices offset by (1/4,1/4,1/4)ao in the primitive cell. The cations Cd and Hg are statistically mixed on the yellow sublattice while the Te anions form the grey sublattice in the ima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoconductor
Photoconductivity is an optical and electrical phenomenon in which a material becomes more electrically conductive due to the absorption of electromagnetic radiation such as visible light, ultraviolet light, infrared light, or gamma radiation. When light is absorbed by a material such as a semiconductor, the number of free electrons and holes increases, resulting in increased electrical conductivity. To cause excitation, the light that strikes the semiconductor must have enough energy to raise electrons across the band gap, or to excite the impurities within the band gap. When a bias voltage and a load resistor are used in series with the semiconductor, a voltage drop across the load resistors can be measured when the change in electrical conductivity of the material varies the current through the circuit. Classic examples of photoconductive materials include: * photographic film: Kodachrome, Fujifilm, Agfachrome, Ilford, ''etc.'', based on silver sulfide and silver bromide. * t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Imager
A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example of convection, specifically atmospheric convection. Thermals on Earth The Sun warms the ground, which in turn warms the air directly above. The warm air near the surface expands, becoming less density, dense than the surrounding air. The lighter air rises and cools due to its expansion in the lower pressure at higher altitudes. It stops rising when it has cooled to the same temperature, thus density, as the surrounding air. Associated with a thermal is a downward flow surrounding the thermal column. The downward-moving exterior is caused by colder air being displaced at the top of the thermal. The size and Power (physics), strength of thermals are influenced by the properties of the lower atmosphere (the ''troposphere''). When the air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron
The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure. The electron's mass is approximately 1/1836 that of the proton. Quantum mechanical properties of the electron include an intrinsic angular momentum ( spin) of a half-integer value, expressed in units of the reduced Planck constant, . Being fermions, no two electrons can occupy the same quantum state, in accordance with the Pauli exclusion principle. Like all elementary particles, electrons exhibit properties of both particles and waves: They can collide with other particles and can be diffracted like light. The wave properties of electrons are easier to observe with experiments than those of other particles like neutrons and protons because electrons have a lower mass and hence a longer de Broglie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Imaging
Infrared thermography (IRT), thermal video and/or thermal imaging, is a process where a thermal camera captures and creates an image of an object by using infrared radiation emitted from the object in a process, which are examples of infrared imaging science. Thermographic cameras usually detect radiation in the long-infrared range of the electromagnetic spectrum (roughly 9,000–14,000 nanometers or 9–14 μm) and produce images of that radiation, called thermograms. Since infrared radiation is emitted by all objects with a temperature above absolute zero according to the black body radiation law, thermography makes it possible to see one's environment with or without visible illumination. The amount of radiation emitted by an object increases with temperature; therefore, thermography allows one to see variations in temperature. When viewed through a thermal imaging camera, warm objects stand out well against cooler backgrounds; humans and other warm-blooded animals become ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Imaging Common Modules
Forward-looking infrared (FLIR) cameras, typically used on military and civilian aircraft, use a thermographic camera that senses infrared radiation. The sensors installed in forward-looking infrared cameras, as well as those of other thermal imaging cameras, use detection of infrared radiation, typically emitted from a heat source (thermal radiation), to create an image assembled for video output. They can be used to help pilots and drivers steer their vehicles at night and in fog, or to detect warm objects against a cooler background. The wavelength of infrared that thermal imaging cameras detect is 3 to 12 μm and differs significantly from that of night vision, which operates in the visible light and near-infrared ranges (0.4 to 1.0 μm). Design Infrared light falls into two basic ranges: ''long-wave'' and ''medium-wave''. Long-wave infrared (LWIR) cameras, sometimes called "far-infrared", operate at 8 to 12 μm and can see heat sources, such as hot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yellow Duckling
Yellow Duckling was an early development of an infrared linescan camera, developed for the detection of submarines during the Cold War. The name is one of the series of British Rainbow Codes. Origins Infrared detection systems had been considered as far back as the 1930s. During World War II, the Germans were the innovators in this field. Studies of captured FuG.280 Kielgerät from a Ju 88G night fighter showed the use of a lead sulphide (PbS) detector. This was developed by the British at TRE into a lead telluride (PbTe) detector and the use of liquid nitrogen cooling to improve sensitivity and extend the lower range of temperatures it could detect. Kielgerät also demonstrated the use of a rotating 'chopper' mirror and a simple form of boxcar integrator to extract a usable signal from a noisy detector. These early detectors had no scanning or imaging ability: they detected heat sources at a single spot. To make them militarily useful they were generally mounted as par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Imaging
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of Light, visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 Terahertz (unit), THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to Wave–particle duality, both those of a wave and of a Subatomic particle, particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed rad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Military Electronics Of The United Kingdom
A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct military uniform. It may consist of one or more military branches such as an army, navy, air force, space force, marines, or coast guard. The main task of the military is usually defined as defence of the state and its interests against external armed threats. In broad usage, the terms ''armed forces'' and ''military'' are often treated as synonymous, although in technical usage a distinction is sometimes made in which a country's armed forces may include both its military and other paramilitary forces. There are various forms of irregular military forces, not belonging to a recognized state; though they share many attributes with regular military forces, they are less often referred to as simply ''military''. A nation's military ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
