Passive infrared detectors

Dual-technology sensors consist of two different sensor technologies incorporated together into one sensor unit. For example, a dual technology sensor could consist of a passive infrared detector and a monostatic microwave sensor integrated into the same sensor unit. 

Type of Interior Sensor Passive infrared (PIR) Presently the most popular and cost-effective interior sensors. PIR detectors monitor infrared radiation (energy in the form of heat) and detect rapid changes in temperature within a protected area. Because infrared radiation is emitted by all living things, these types of sensors can be very effective. 

Cadmium telluride — A II—IV compound -> semiconductor frequently employed in infrared systems (active component in infrared detectors) and -> photovoltaic devices. Electrochemical - passivation has been employed to improve surface recombination behavior. 

Mercury cadmium teiluride (HgCdTe) is a direct bandgap semiconductor widely used as a material for infrared detectors due to his narrow variable band gap. The achievement of high-performance detectors depends critically on a low surface recombination velocity of the minority carriers. The chemical growth of a passivation oxidized superficial layer in an aqueous Fe(CN)g3- basic solution is studied in this work. The depth profiles of the different elements in the oxidized layer superficial layer and its thickness are studied by X-ray photoelectron spectroscopy. The electrical properties of the interface are evaluated from MIS devices. The conditions of oxidation have been optimized. 

Joint Service Lightweight Standoff Chemical Agent Detector (JSLSCAD). The JSLSCAD is a passive, infrared detection unit employing Fourier Transform Infrared (FTIR) Spectrometry. The device is designed to detect nerve and blister vapor clouds at a distance of up to 5 km. 

The HAWK is a portable instrument that uses infrared for stand-off remote sensing detection of a chemical cloud. It is a passive IR detector that identifies the characteristic signatures of chemicals in the near-infrared spectrum. Identification is made through spectrum... 

Given the above statistics security lighting is undoubtedly a cost-effective way of reducing the incidence of arson attacks. In many premises such lights may be operated by passive infrared (PIR) detectors and not only provide illumination but also produce an element of surprise. PIR is also seen as being more acceptable in built-up areas due to the nuisance caused by permanent Illumination. 

The basic near range sensors are the infrared and ultraviolet detectors, often coming together as IR/UV-sensor, in most cases in a line-scanner (LS) assembly. The IR/UV-LS is a passive bi-spectral remote sensor that is sensitive in the thermal infrared (TIR) between 8 and 14 pm and in the near ultraviolet (NUV) between 0.32 and 0.38 pm. At an aircraft altitude of 300 m its swath width amounts to approximately 500 m. This sensor on the one hand is used to measure the thermal emission of the sea surface in the TIR and on the other hand serves for the detection of highly reflecting... 

The advent of micro and nanophotonics has brought astounding enhancements to different passive and active devices. In the field of infrared technologies, MEMS and NEMS, it ensured the appearance of a new generation of thermal detectors,... 

In Chapter 3, R.T, Talasek reviews the anodic passivation of ll-VI semiconductors such as the (Hg,Cd)Te alloys used in infrared imaging detectors. This is one area of electronics in which electrochemical methods have already become the industrial standard. 

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