Abstract: Surveillance systems of this invention incorporate a charge coupled device image sensor with an illumination source that is made of an emitter which concentrates its optical output in a narrow band at or about the peak optical response of the photoconverter being used. Where a silicon imaging sensor is being used, the illumination system can comprise an emitter made of a rare earth oxide, such as ytterbium oxide, in the form of a filamentary network and fuel to energize the emitter. Different emitters can be employed to achieve the optimal radiant energy for any type of photoconverter device, including those based on silicon, germanium, indium gallium arsenide, and gallium antimonide. These surveillance systems may be applied in a number of specialized applications, such as, for example, in the covert surveillance of commercial, industrial, residential, or military sites, or any site in which the visible illumination of the surveillance area is undesirable.

Abstract: The concentration of a target gas is determined in an optical gas sensor system having an array of optical gas sensors wherein each sensor has a different sensitivity range for a target gas. An active sensor is selected from the array of optical gas sensors by determining which sensor has an optical transmittance value between 0% and 100%. Optical transmittance values of the active sensor are differentiated with respect to time. Concentration of the target gas is calculated as a function of both the rate of change of optical transmittance and the value of the optical transmittance at the beginning of the period over which the transmittance is differentiated. When a hazardous gas such as carbon monoxide is the target gas an alarm can be given when a threshold concentration is exceeded. Preferably, the transmittance values are converted to digital signals and processed in an eight-bit microprocessor to determine target gas concentration.

Abstract: A thermophotovoltaic electric generating system provides high thermal to electric conversion efficiency by use of a sequence of matched radiation emitters and radiation collectors. The radiation emitters comprises ceramic materials which emit thermally stimulated quantum radiation in at least one characteristic wavelength bands when heated above a threshold temperature. By employing a sequence of selective emitters such as rare earth metal oxide, more than 50% of the radiation emitted from the surface can be concentrated in two or more characteristic wavelength bands. A sequence of corresponding photovoltaic device selectively absorbing and efficiently converting the radiation at the characteristic wavelength bands for high electric conversion efficiency in each zone, respectively. An overlying layer of the photovoltaic collector selectively absorbs at least one of such characteristic wavelength bands.

Abstract: A detector sensor system for sensing the presence of a toxic gas, such as carbon monoxide and/or smoke whereby a corresponding alarm is sounded. The presence of the gas is detected by passing light through a biomimetic sensing material in which the optical characteristics change in the presence of the target gas. This system includes a housing containing a light emitter, light detector and a mechanism for sounding an alarm. The sensing material is contained in a cell which, together with a battery to power the system, is mounted in a key insertable into the housing. The key may be readily inserted or withdrawn from the housing for replacement purposes. When fully inserted, the key positions the sensing cell means between the light emitter and detector means and brings the battery contacts carried therewith into connection with contacts associated with the system circuitry mounted within the housing.

Abstract: A carbon monoxide (CO) detection system is connected into an anesthesia gas delivery system. The system comprises, among other things, a CO sensor unit containing an inexpensive, replaceable sensor that detects the presence of CO in anesthesia, an in-line adapter that exposes the detection unit to the main stream of the gas and can be placed in a variety of different locations along the gas stream and a side-stream adapter for the removal and analysis of gas stream samples using a CO sensor unit outside of the main gas stream. There is also apparatus capable of measuring the response of the sensors to CO exposure, and data acquisition and a data processing unit for storing, processing and displaying the CO sensor response data. In a preferred embodiment there is a carbon monoxide detection system comprising a detection unit including a sensor unit and a measurement unit. The sensor unit detects carbon monoxide based on the change or rate of change of the optical characteristics of the sensor unit.

Abstract: A multilayer matrix burner which has exceptionally low NO.sub.x emissions can be operated over a broad turndown range. The burner is, in effect, a three-dimensional matrix of spaced apart emissive layers. There is a first three-dimensional porous layer which acts to distribute a fuel/air mixture. There is a wider gap (which may be adjustable) between the distributive layer and one or more two-dimensional porous emissive layers. An exemplary emissive layer is a refractory wire screen. Preferably, there are multiple such emissive layers with a narrower gap between successive layers. Preferably, the porosity increases in each successive layer downstream from the preceding layer. This arrangement provides a stable flame wherein most of the combustion occurs adjacent to successive incandescent emissive layers. Preferably the successive layers in the downstream direction have a large open area for transmitting radiant energy from preceding emissive layers. Such high intensity burners, e.g. 1,500,000 BTU/h.multidot.

Abstract: An improved carbon monoxide sensor system has a dual sensor system having two sensors disposed in a series arrangement within a sensor housing. Each sensor is formed from a porous semi-transparent substrate that is impregnated with a different chemical sensor reagent. At lease one sensor substrate surface is treated with a chemical compound before being impregnated to increase average pore size and, thereby, increase the sensitivity of the sensor. One sensor is formed from a chemical sensor reagent designed to perform at a lower to middle humidity and temperature range. The other sensor is formed from a chemical sensor reagent designed to perform at a middle to high humidity and temperature range. The dual sensor system constructed in this manner provides good carbon monoxide sensitivity at temperature and humidity conditions required by the standards of UL-2034.

Abstract: An enclosure for a gas detector including an easily removable and replaceable battery/sensor holder and a battery absence indicator. The enclosure includes a flat first panel adapted to be fastened into a ceiling, a second panel spaced from the first panel to contain the gas detecting apparatus and a sidewall closing between the edges of the panels. A specially configured opening is provided to allow sound from an audio alarm to exit the enclosure. Another opening in the second side panel is configured to receive and retain a battery holder through a cooperating bayonet type arrangement of radial protrusions on the holder and notches in the sides of the opening. A tube is contained in the opening in such a way as to permit the tube to extend when the holder is removed to signal the absence of the holder. The tube is pushed back into the enclosure when the battery/sensor holder is inserted.

Abstract: Photon generating devices produce predetermined radiation spectral output and heat for a variety of applications including lighting and electric power generation, and provide photons to enhance chemical and physical reactions. Such a device comprises an emitter which contains metal oxides, means to heat the emitter sufficiently to produce large number of photons of a desired spectral output, and an optical means for directing the photons to various targets. In one embodiment, the device includes a thermal input device, a light pipe having a low emissivity, and an emitter coating of superemitter material which is thermally stimulated to emit radiation of a specific wavelength above a threshold temperature. An intermediate layer may be used to bond the emitter coating to the light pipe or other optical device where desired.

Abstract: A superemissive light pipe includes a photon transmitting optically transparent host having a body and oppositely arranged end portions. In one embodiment, superemissive material is disposed within the host and an optical cladding is disposed onto an outside surface portion of the host. The superemissive material emits photons upon thermal stimulation. The optical cladding reflects photons emitted by the superemissive material toward the host and directs the photons to the end portions. The optical cladding has an index of refraction different from that of the host. In another embodiment, a layer of superemissive material is interposed between the surface of the host and the optical cladding. A thermal energy source is either disposed internally within the host, in the form of radioisotopic particles that undergo nuclear decay, or externally outside of the light pipe, in the form of a general purpose heating source, to effect photon emission by the superemissive material.

Abstract: In a gas-fired stove or oven, gas is burned in a porous ceramic surface combustion burner which generates selective emissive radiation in a narrow band. The high temperature surface of the burner includes a narrow band quantum emitting substance such as rare earth metal oxide. Relatively shorter wavelength radiation from this quantum emitting surface illuminates process targets having an absorption spectrum nearly matched to the emission spectrum of the burner surface, for a variety of applications such as cooking. The selected emission may be passed through a glass top stove to heat a pot with an absorptive bottom or may pass on through a glass pot to heat the food directly.

Abstract: A combustion device for producing predetermined radiation spectral output and heat for a variety of applications including lighting, cooking, heating water, electric power generation, and providing inexpensive photons to enhance chemical and physical reactions.A process for the preparation of a porous ceramic burner is described which comprises drawing a solution which contains metal oxide fibers onto a burner skeleton by use of a vacuum to form a base fiber layer. The base fiber layer is dried, after which an additional metal oxide fiber layer, the outer fiber layer, is added over the base fiber layer. In another embodiment of the invention, an intermediate fiber layer is placed over the base layer, prior to the addition of the outer fiber layer.

Abstract: Embodiments of gas-fired appliances which generate selective emissive radiation, in such apparatus, gas is burned in a porous ceramic surface combustion burner. The high temperature surface of the burner includes a narrow band quantum emitting substance such as rare earth metal oxides. Relatively shorter wavelength radiation from this quantum emitting surface illuminates process targets having an absorption spectrum nearly matched to the emission spectrum of the burner surface, for a variety of application such as cooking. The selected emission may be passed through a glass top stove to heat a pot with an absorptive bottom or may pass on through a glass pot to heat the food directly.

Abstract: A detector system for sensing the presence of a toxic gas, such as carbon monoxide, and sounding an alarm. The presence of the gas is detected by passing light through a biomimetric sensing material that darkens in the presence of the gas. The system includes a housing containing a light emitter, a light detector and a mechanism for sounding an alarm. The sensing material is contained in a cell, which, together with a battery to power the system, are mounted in a drawer insertable into the housing, which has openings permitting ambient air to reach the sensing material. When fully inserted, the drawer positions the cell between the emitter and detector and brings battery contacts into connection with contact s for the light emitter and alarm. Both the battery and sensing material must be replaced periodically, typically about once every three years. The drawer is configured so that it cannot be inserted without a battery in place. Both the battery and cell are easily replaced in the drawer.

Abstract: The present invention relates to a biomimetic sensor for detecting the presence of airborne toxins, such as carbon monoxide, mercury, ethylene oxide, volatile organic materials, and hydrogen sulfide. The biomimetic sensor, which has a functional life of at least one year, comprises a porous, semi-transparent substrate into which is impregnated a self-regenerating chemical sensor reagent. The response of the biomimetic sensor mimics the human response to such toxins, with respect to sensitivity and affinity. The extended functional lifetime of the biomimetic sensor and the mimicking of the human response to the toxins are achieved by the use of a molecular encapsulant that encapsulates at least one component of the chemical sensor reagent.

Abstract: Embodiments of gas-fired appliances which generate sufficient electricity to be self-powered include water heaters, space heaters, air conditioning units, and electric power and steam cogeneration systems. In such apparatus, gas is burned in a porous ceramic surface combustion burner. The high temperature surface of the burner includes a narrow band quantum emitting substance such as a rare earth metal oxide and preferably ytterbium oxide. Relatively shorter wavelength radiation from this quantum emitting surface illuminates photovoltaic cells having an absorption spectrum matched to the emission spectrum of the burner surface for generating sufficient electricity for powering the appliance. An infrared absorbing filter removes relatively longer wavelength radiation which would otherwise heat the photovoltaic cells. The cells are cooled, preferably by a portion of the utility fluid heated by the appliance.

Abstract: The system utilizes a radiation sensing device which views an electrically heated emissive igniter to provide proof-of-ignitability detection of the igniter. Optimally a photovoltaic array may be employed to self-power the electronic circuitry and fuel intake valve to the burner of a combustion device. In one embodiment there is also provides a second emission device viewed by the first photovoltaic array or a second photovoltaic device which views a second emissive device which is thermally heated upon activation of the burner. The electronic signals generated by the second light sensing device can be used to prove ignition of the combustion gases. When the second light sensing device is a photovoltaic array, power may be generated for recharging a storage battery, which in turn, can be used to electrically heat the emissive igniter. In the simpler case where the second emissive device is powered by the gas flame, means are provided for turning off the igniter.

Abstract: A model of human female breast for teaching breast examination comprises an opaque, elastomeric membrane simulating skin, a transparent backing member connected to the opaque membrane to define a chamber therebetween, first means simulating adipose tissue disposed in the chamber, at least one second means simulating a tumor within the chamber and opaquing means overlying and being removably attached to the transparent backing member. In addition, the present invention is directed to a method of training a person to detect breast tumors by palpating said model.

Abstract: A fail safe gas shut off system is provided for a gas appliance. Two normally closed valve stages are provided in series, with each stage operated by a bidirectional solenoid armature. When the armature moves in one direction, the first stage of the valve is opened to supply gas to a pilot burner and to the second stage of the valve. When the pilot flame heats an emissive element to produce sufficient radiation, a photovoltaic device illuminated by the emissive element produces current for an electromagnet which latches the first stage of the valve in its open position. The armature can then move in the opposite direction and open the second stage of the valve to supply gas to the main burner. In the event of pilot flame failure, the emissive element darkens, and current from the photovoltaic device ends. The electromagnet releases the first stage of the valve which is biased closed and cuts off gas flow to both the pilot and main burners.

Abstract: An apparatus (1) is disclosed for controlling oxidation of a fuel in an oxidation source (2,3). The apparatus includes photovoltaic means (5) for receiving electromagnetic radiation (6) from the oxidation source and for producing electric power having a given electric power magnitude. An oxidation control (8, 1A, 1B, 288, 325) is coupled to, and driven, by, the photovoltaic means for controlling the oxidation. The oxidation is adjusted when the electric power is less than the given electric power magnitude. Oxidation may also be adjusted when a hazardous gas is detected. The apparatus (1A) may be used to power various electronic circuits. The apparatus (1B) may also be used to maintain the efficiency of the combustion source. A novel arrangement (248) for operating a fuel control valve is also disclosed. An apparatus (418) for controlling a portable heater is also disclosed.