Abstract: A flame detection system includes a plurality of sensors for generating a plurality of respective sensor signals. The plurality of sensors includes a set of discrete optical radiation sensors responsive to flame as well as non-flame emissions. An Artificial Neural Network may be applied in processing the sensor signals to provide an output corresponding to a flame condition.

Abstract: A flame detection system includes a plurality of sensors for generating a plurality of respective sensor signals. The plurality of sensors includes a set of discrete optical radiation sensors responsive to flame as well as non-flame emissions. An Artificial Neural Network may be applied in processing the sensor signals to provide an output corresponding to a flame condition.

Abstract: A method and apparatus for the fabrication of an electro-chemical sensor housing structure. A plastic cover member is positioned in contact with a sensor housing structure. The housing structure fabricated of a plastic material with high absorption to laser radiation. Laser energy is transmitted through the cover member, fabricated of a material that transmits the laser energy, onto a weld area at a joint between the cover member and the housing structure to weld the cover member to the housing structure at the joint.

Abstract: A flame detector consisting of a first infrared radiation detector for detecting radiation from combustion of hydrocarbon and other carbon containing compounds in conjunction with a second infrared radiation detector for distinguishing radiation from other sources such as modulated sunlight, reflections, artificial as well as natural hot objects, illuminating light sources, and arc welders. The flame detector uses two electronic circuits following the first infrared detector such that a fire is sensed by either of the two circuits depending on its size, one circuit being optimized for flicker frequencies present in a large fire while the second circuit simultaneously checks for optical signals at flicker frequencies dominant in a smaller fire. The two electronic outputs along with the output of the second infrared detector are digitally processed and analyzed for spectral and temporal characteristics to distinguish the presence of a real fire from that of various false alarm sources.

Abstract: Apparatus for the optical detection of selected toxic gases, using the ultraviolet region of the electromagnetic spectrum, and the known absorption properties of the toxic gases in the ultraviolet region. An ultraviolet flashlamp source illuminates a straight, highly polished metal tube with numerous perforations to permit access for the gas to be detected. The ultraviolet light then enters an optical compartment comprising an optical beamsplitter and two ultraviolet detectors with wavelength selective narrowband filters attached. The filters are selected so that one overlaps the region of absorption by the gas while the second is in a region where there is no absorption by the gas. The electronic circuit following the ultraviolet detectors and the drivers for the flashlamp, are timed by a microprocessor that provides the means for the electronics and data processing to be synchronized with the flashlamp pulse.

Abstract: Apparatus for the optical detection of flames or explosions, having an optical structure to perform continuous optical path monitoring of the optical window receiving the optical radiation, to ensure against the buildup of radiation absorbing or scattering materials. A light source internal to the housing illuminates a straight optically transmissive quartz or sapphire rod that protrudes through the housing beyond the optical window. The protruding tip of the light rod is beveled and metallized on the bevel to provide internal reflection of the light from the source, the angle of the bevel being such that the reflected light on exiting the light rod illuminates the optical window and the optical detector behind it, thereby providing a test for the cleanliness of the optical window. This optical technique for checking the cleanliness of the optical viewing element can be utilized by other optical instruments including imaging arrays, surveillance cameras and weapons.

Abstract: A method and apparatus for mounting pyroelectric crystal elements and arrays on a molded plastic base. The molded plastic base includes a plurality of upwardly tapered plastic flexible legs which engage the pyroelectric crystal element or array at various points. The upwardly tapered plastic legs reduce to a nominal thickness of approximately 0.002 inches where they are fastened by epoxy onto the pyroelectric crystal element or array.