Abstract:
The present invention relates to a method of manufacturing radiation detectors, in which these detectors each comprise a set of microdetectors, for example microbolometers, situated under a window that is transparent to said radiation. According to the invention, said detectors are manufactured collectively on a substrate (1), and said method comprises notably the following steps: the construction of several layers, of which, for each of said detectors, at least one layer (4) is transparent to said radiation and serves as a window, and the partial elimination of said layers principally under said transparent layer(4), such that said microdetectors (2) are placed, for each of said detectors, in one or more cavities, which are then placed under vacuum or under low pressure. The invention also relates to various radiation detectors, of which the walls form hermetically sealed cavities each containing one or more microdetectors (2).
Abstract:
Arrays of pyroelectric elements are used in surveillance systems by focusing the radiation from a scene on to them and examining the output from the array. If an object is moved into the scene and left stationary, it will hinder the subsequent operation of the system by masking part of the scene from the field of view of the array; this fault condition may be detected by the following procedure. At intervals arrangements are made to move the image of the scene to and from across the array using a suitable transducer and the outputs from the array are examined. The outputs from the array when the scene is in its normal condition and the image is moved across the array comprise a set of signals corresponding to a reference image, which may be compared with the corresponding outputs from the array when the image is moved across the array on a subsequent occasion. Change between the reference image signals and subsequent image signals are interpreted in terms of the introduction to, or removal of, objects from the scene.
Abstract:
Single crystal SiC at least 200 micrometers thick is employed to detect electromagnetic radiation having a wavelength less than about 10 micrometers via an acoustic absorption mechanism. Applications include IR radiation sensing, contactless temperature sensing and an IR controlled varistor.
Abstract:
A thermal infrared detector has a substrate having a readout circuit and a plurality of pixels patterned on the substrate at a pitch p, which is in the range of from 15 to 50 micrometers. Each of the pixels has a photo-sensitive bolometer thin film area that is spaced from the substrate, and supported by two beams which contain interconnections between the photosensitive area and the readout circuit. The length of each of the beams is determined by the patterning accuracy of a stepper used to produce the thermal infrared detector, based on a beam length index calculated by dividing the length of each beam by one-quarter of the peripheral length of the pixel. The beam length index may be approximated by an expression using the pixel pitch, the thermal conductivity of the interconnection material, etc. as parameters in an equation representing temperature resolution.
Abstract:
A microbolometer unit cell (10) includes a substantially planar upper-level incident radiation absorption and detection structure (24), a substantially planar middle-level radiation reflection structure (26) spaced apart from the upper-level incident radiation absorption and detection structure for defining an optical resonant cavity (36) there between, and a substantially planar lower-level thermal isolation leg structure (20) spaced apart from the middle-level radiation reflection structure and electrically coupled to the upper-level incident radiation absorption and detection structure and to an underlying readout circuit. The lower-level thermal isolation leg structure is electrically coupled to the upper-level incident radiation absorption and detection structure through a leg (44) that passes through an aperture (48) within the middle-level radiation reflection structure, the leg also functioning as a structural support member. The lower-level thermal isolation leg structure is electrically coupled to the readout circuit through another leg (18) that terminates on an electrical contact (16) disposed on an underlying readout integrated circuit (12), and the middle-level radiation reflection structure is supported by an extension of the leg (18A).
Abstract:
An ultraviolet target designator and methodology that utilizes ultraviolet radiation from a laser designator to remotely designate targets for various applications. In one embodiment, the ultraviolet laser designator is used to remotely designate a target for insects to fly to so as to collect environmental information. In another embodiment, the ultraviolet laser operates in the solar blind region to remotely designate a target. When used in conjunction with a solar blind camera, the targeting can be performed without detection by infrared or visible detection devices.
Abstract:
The present invention intends to improve the accuracy of temperature measurement when measuring the temperature of a semiconductor wafer by a radiation thermometer on the basis of the idea of virtual blackbody simulated by multiple reflection of light. A system includes a wafer (W), a circular reflector 1 of a radius R disposed opposite to the wafer (W), and a probe (2) disposed in a through hole formed in the reflector (1). The probe (2) is a through hole. The radiation intensity of radiation passed the through hole is determined by image data provided by a CCD camera disposed behind the back surface of the reflector (1). An error in measured radiation intensity of radiation falling the probe (2) due to light that enters a space between the wafer (W) and the reflector (1) and a space between the reflector (1) and the probe (2) and light leaks from the same spaces is corrected, the emissivity of the wafer (W) is calculated and the temperature of the wafer (W) is determined.
Abstract:
A process for determination of blackening of a lamp in which the blackening of a lamp can be determined without visual inspection in real time or during operation is achieved by the spectral radiant energy which is emitted by the lamp bulb being measured and evaluated based on the difference that exists between when blackening occurs as compared to when blackening does not occur. Therefore, blackening of a lamp can be determined by determining the change of the spectral radiant energy emitted by the bulb. Furthermore, in a lamp in which the bulb temperature changes, the spectral radiant energy emitted by the bulb can be measured at two different wavelengths and blackening of the lamp can be determined based on the change of the ratio relative to each other.
Abstract:
A pyrometer for measuring the temperature of an object with high accuracy and fast response time that uses both multi-wavelength pyrometry techniques and nanotechnology. Radiance from an object is transmitted through a fiber optic cable, is received by a thin-film multi-wavelength modulator, and is detected by an optical detector array. More specifically, the pyrometer includes means for conveying light; an optical lens; an optical fiber; means for optically modulating the wavelength of light; means for optically detecting the modulated light; means for transforming the optically detected wavelengths into electrical signals; and means for processing and recording the electrical signals. The means for optically modulating the wavelength includes at least one piezoelectric film deposited by an electrostatic self-assembly method. The pyrometer can be fabricated as either a contact-mode or non-contact mode device, both of which are suitable for use in hostile environments such as a boiler, gasifier, kiln and furnace.
Abstract:
A radiation thermometer that avoids deterioration of measurement accuracy or loss of hygiene due to a dirty front end of a probe portion of the radiation thermometer, lowers running costs which are created if a probe cover is used, and reduces the labor of procuring the probe cover. To this end, the front end of the probe portion of the radiation thermometer has a waterproof structure so that the front end of the probe portion can be wiped with alcohol or the like.