Abstract:
An improved gas detector apparatus includes a spectral source/bolometer for conducting an electrical current and for producing infrared radiation. The source/bolometer has a characteristic resistance that is a predetermined function of the source/bolometer temperature. A concentrating reflector directs the infrared radiation through a spectral filter and the gas. A return reflector is disposed along the axis beyond the spectral filer and the gas, such that at least a portion of the infrared radiation passing through the filter and the gas is reflected back through the gas and the filter to the source/bolometer. A driver/detector drives a current through the source/bolometer, determines the characteristic resistance of the source/bolometer, and detects the gas from a variation of the characteristic resistance.
Abstract:
A blackbody radiation device (110) includes a planar filament emission element (102) and a planar detector (104) for respectively producing and detecting radiation having width dl/l less than about 0.1 to test a sample gas, where l is the wavelength of the radiation; a reflector (108); a window (W); an electrical control (118); and a data output element (116).
Abstract:
An infrared emitter, which utilizes a photonic crystal (PC) structure to produce electromagnetic emissions with a narrow hand of wavelengths, includes a semiconductor material layer, a dielectric material layer overlaying the semiconductor material layer, and a metallic material layer having an inner side overlaying the dielectric material layer. The semiconductor material layer is capable of being coupled to an energy source for introducing energy to the semiconductor material layer. An array of surface features are defined in the device in a periodic manner or quasi-periodic. The emitter device is adapted to emit electromagnetic energy having spectral characteristics determined by parameters of the periodically distributed surface features, the parameters including shape, size, depth, distribution geometry, periodicity, material properties and defects.
Abstract:
An improved IR radiation source is provided by the invention. A radiation filament has a textured surface produced by seeded ion bombardment of a metal foil which is cut to a serpentine shape and mounted in a windowed housing. Specific ion bombardment texturing techniques tune the surface to maximize emissions in the desired wavelength range and to limit emissions outside that narrow range, particularly at longer wavelengths. A combination of filament surface texture, thickness, material, shape and power circuit feedback control produce wavelength controlled and efficient radiation at much lower power requirements than devices of the prior art.
Abstract:
A gage mechanism for a blood pressure measuring device or other similar apparatus includes a supported shaft member having one end in contact with an inflatable bellows. A pointer is attached at an opposite end of the shaft and a helically wound spring is attached to the shaft and a supporting structure. As the bellows inflates, the shaft is axially displaced and causes rotation due to the constraint of the helical ribbon spring, causing a corresponding angular deflection of the attached pointer relative to an indicating scale. The mechanism includes a first adjustment member for allowing the pointer to be preset to a zero or calibrated position, and a second adjustment mechanism that controls the amount of angular rotation of the shaft and pointer for a displacement of the bellows.