Abstract: A new type of mounting mechanism for a light detector that cools the mounting for a light detector such that the maximum efficiency of the light detector's internal cooler can be achieved despite an elevated enclosure temperature, leading to more stable measurements of light from the detector. This same mounting provides thermal isolation from a baseplate, to which other optical path components are attached.

Abstract: A remote sensor for use as a handheld, mobile or stand-alone sensor has first (12) and second (16) optical paths, light collecting optics, a sample filter (10) assembly positioned in a first optical Path (12), a reference filter (14) assembly positioned in a second optical path (16), a detector assembly to detect the filtered light r other radiation, and a detector output comparison device such as BRD to minimize the effects of common background noise components, differences in light or other radiation source power, and absorption or emission by interfering species.

Abstract: A spray data acquisition system includes a pumping device responsive to an applied force to generate an aerosol spray plume along a spray axis. The system further includes a spray pump actuator that is capable of controlling the pumping force and the duration of the aerosol spray plume produced by the pumping device. The system also includes an illumination device that illuminates the aerosol spray plume along at least one first geometric plane that intersects the aerosol spray plume. The system further includes an imaging device that acquires data representative of an interaction between the illumination and the aerosol spray plume along at least one geometric plane.

Abstract: An optical system for a gas component analysis includes an emitter for emitting first light beam having a first spectrum, a second emitter for emitting a second light beam at a second spectrum, a first receiver for receiving the first light beam, and a second receiver for receiving the second light beam.

Abstract: A control device and method provides control of at least one operating feature of a cooking device in response to measured smoke and/or gas produced by item(s) being cooked. The device and method may control the temperature and cooking time of the device, and may also shut off the device or provide a fire alarm.

Abstract: A gas component analysis system transmits, reflects, and detects light using infrared light source; a reflector unit; and a light detector. The light is transmitted through a gas, such as air containing vehicle emissions, reflected, and detected for analysis and measurement of the amount of absorption that has occurred at known wavelengths. The amount of absorption may be used to determine concentrations of reference gases corresponding to specific wavelengths.

Abstract: The present invention provides for an apparatus, method, and system for mapping out each pollutant and its locality. The apparatus includes a cell where pollutants can be collected in with an optical channel having multiple passes of radiation within the cell. The cell requires a valve acting like a vacuum for allowing pollutants in the atmosphere to be deposited in the cell for detection. A location sensor is provided for determining a location coordinate of the cell. The mappable atmospheric pollutant detection system utilizes laser technology with a computer system.

Abstract: A photoacoustic sensor that measures carbon black particles emitted in the exhaust gas of a vehicle traveling on a road or being tested on a dynamometer or engine stand. The sensor includes an acoustic waveguide and a pump mounted to an outlet of the waveguide. The pump pulls the gas through the waveguide. A critical orifice is mounted between the pump and the outlet. The critical orifice prevents noise generated by the pump from entering the waveguide. Optical windows are mounted at opposite ends of the waveguide. A modulated source of light is located adjacent one of the windows and irradiates the waveguide. A microphone is attached to the waveguide. The microphone detects an acoustic signal generated by absorption of the light by the particles in the gas. The acoustic signal is proportional to the mass concentration of particles in the gas. The microphone generates an electrical signal proportional to the acoustic signal.

Abstract: Excess oxygen in the combustion process of a facility that bums carbon-based fuels may cause a visible plume in the atmosphere at the stack of the facility. Traditional optical based opacity monitors may be unable to detect this plume or the plume may form at a location downstream from the opacity monitor toward the stack. The present invention discloses methods to utilize common combustion control variables to detect and signal the presence of a visible plume of exhaust gasses. Also disclosed are systems that detect the visible plume and provide a signal so that the combustion process may be manually or automatically adjusted to reduce or eliminate the visible plume.

Abstract: A smoke detector includes a housing defining a dark chamber admitting test atmosphere. A light receiver is disposed within the chamber. A scatter emitter is positioned within the chamber such that light strikes the receiver when reflected off particles suspended in the test atmosphere. An obscuration emitter is positioned within the chamber such that light emitted is directed to the receiver unless obstructed by particles suspended in the test atmosphere. A smoke detect signal is generated responsive to a measurement made responsive to the scatter emitter and/or the obscuration emitter.

Abstract: A method and apparatus for analyzing a picture of an effluent such as a smoke plume or dust cloud to determine the opacity of the effluent. The picture of the effluent is first broken down into pixels. Each pixel corresponding to the effluent is identified and the color of each effluent pixel is analyzed to calculate the opacity of that effluent pixel. An opacity value for the entire effluent is extrapolated based on the opacity values of each effluent pixel.

Abstract: A top surface of a wafer is provided with an n-type source region, an n-type drain region, and an n-type semiconductor region. Dry etching using a plasma is performed with respect to an interlayer insulating film deposited on the wafer to form openings reaching the respective regions, followed by light etching for removing a damaged layer. In this case, exciting light is supplied intermittently to the n-type semiconductor region. The progression of the removal of the damaged layer and the stage of development of a newly damaged layer are sensed by monitoring the change rate of the intensity of reflected probe light in the presence and absence of the exciting light, resulting in the formation of a semiconductor device having low and equal contact resistance. In-line control using optical evaluation enables the implementation of semiconductor devices with excellent and consistent properties.

Abstract: A smoke density monitor for mounting on a ship smokestack. The smoke density monitor provides a transmitter head and a receiver head mounted to a smokestack. The transmitter head and receiver head are optically connected with a density monitor by means of fiber-optic lines. The density monitor is electrically connected to an alarm monitor, which at pre-set smokestack smoke densities activates an alarm and/or shuts down the ship's burner(s). An optional recorder may be connected to the alarm monitor to preserve a record of smoke density. Each transmitter and recorder head has an optical head slidably attached to a head housing for ease of servicing and maintenance.

Abstract: A gas permeable probe for use in an optical analyzer for an exhaust gas stream flowing through a duct or chimney comprises:

Abstract: A gas permeable probe for use in an optical analyzer for an exhaust gas stream flowing through a duct or chimney comprises:

Abstract: A gas permeable probe for use in an optical analyzer for an exhaust gas stream flowing through a duct or chimney comprises:

Abstract: Path Integrated Optical Remote Sensing (PI-ORS) instruments are used to provide Path Integrated Concentration (PIC) data corresponding to a particulate concentration in region scanned by a sequence of optical beams. Prior art methods of developing spatial concentration maps using PIC data have required a relatively large number of intersecting beam paths. The present invention can produce spatial concentration maps using considerably fewer optical beams. Preferably, a non-overlapping radial beam geometry is used to produce PIC data that are processed to produce a spatial concentration map. The PIC data are indicative of the cumulative spatial concentration distribution of the contaminant in the sampling region. Once the PIC data are obtained, a specifically developed reconstruction algorithm is applied to the PIC data to create a map of concentration or contaminants or other constituents in the sampling region. Any of several different reconstruction algorithms can be employed.

Abstract: A fume sensor system that measures the concentration of fume particulate in a boiler and suppresses background noise.

Abstract: A detector device for detecting the presence of airborne particles such as smoke includes a light source, an optical bridge, a measurement path, a reference path, a measurement receiver and a reference receiver. The optical bridge, in addition to the light source and the measurement and reference receivers, are the only optical elements of the detector device. The optical bridge includes two circular apertures arranged downstream of the light source along the radiation path. The light source is arranged in a chamber having an air reservoir, whose surface area is substantially greater than that of the light source. A temperature drift curve is determined by heating the light source and storing the detector signal at different temperatures.

Abstract: An improved self-cleaning oven (10) is provided having an assembly (12) to control the cleaning cycle time of the oven (10) depending upon the degree of oven contamination and soil present therein. The assembly (12) includes a measuring chamber (16) as well as a passageway (18) communicating the interior (14) of the oven (10) and the chamber (16). A smoke detector (32) (preferably an infrared smoke detector) is associated with the chamber (16) and is coupled with a controller (20) so as to measure a parameter of smoke passing through the chamber during at least a portion of the cleaning cycle. This parameter is then used to determine the proper duration of the cleaning cycle. In preferred forms, measuring chamber (16a) is equipped with an ambient air inlet (52) and outlet (54) so as to draw an ambient air stream through the chamber (16a) between the smoke detector (32) and the oven gas stream.

Abstract: A self-contained smoke detector system has internal self-diagnostic capabilities and accepts a replacement smoke intake canopy (14) without a need for recalibration. The system includes a microprocessor-based self-diagnostic circuit (200) that periodically checks sensitivity of the optical sensor electronics (24, 28) to smoke obscuration level. By setting tolerance limits on the amount of change in voltage measured in clean air, the system can provide an indication of when it has become either under-sensitive or over-sensitive to the ambient smoke obscuration level. An algorithm implemented in software stored in system memory (204) determines whether and provides an indication that for a time (such as 27 hours) the clean air voltage has strayed outside established sensitivity tolerance limits. The replaceable canopy is specially designed with multiple pegs (80) having multi-faceted surfaces (110, 112, 114).

Abstract: Two-photon absorption measurements are made at various points remote from monitoring apparatus by apparatus which includes two lasers that produce counter-propagating beams through the earth's atmosphere. The lasers are tuned such that the sum of the energies of the photons in each of the laser beams equals that associated with a predetermined transition of a gas in the earth's atmosphere. In one embodiment, a pulsed laser and a CW laser are used. The pulse from the pulsed laser propagates along the CW beam produced by the CW laser and overlaps the CW beam at positions determined by a range gating technique, which makes possible the measurement of the two photon absorption at the various positions of overlap or coincidence. In one embodiment, the subject apparatus is utilized for pollution monitoring, in which the frequencies of the lasers are tuned such that the energies of the photons from these lasers add up to a transition of a predetermined pollutant.

Abstract: A photoelectric smoke detector includes a photoelectric chamber having a housing fabricated from an electrically conductive material.

Abstract: An improved self-cleaning oven (10) is provided having an assembly (12) to control the cleaning cycle time of the oven (10) depending upon the degree of oven contamination and soil present therein. The assembly (12) includes a measuring chamber (16) as well as a passageway (18) communicating the interior (14) of the oven (10) and the chamber (16). A smoke detector (32) (preferably an infrared smoke detector) is associated with the chamber (16) and is coupled with a controller (20) so as to measure a parameter of smoke passing through the chamber during at least a portion of the cleaning cycle. This parameter is then used to determine the proper duration of the cleaning cycle. In preferred forms, measuring chamber (16a) is equipped with an ambient air inlet (52) and outlet (54) so as to draw an ambient air stream through the chamber (16a) between the smoke detector (32) and the oven gas stream.

Abstract: A control device and method provides control of at least one operating feature of a cooking device in response to measured smoke and/or gas produced by item(s) being cooked. The device and method may control the temperature and cooking time of the device, and may also shut off the device or provide a fire alarm.

Abstract: A hand-held vehicle exhaust analyzer for testing gas content in exhaust emitted from a vehicle is disclosed. The vehicle exhaust analyzer is of a size and weight to be held in a user's hands. The system includes a housing with an inlet receiving exhaust emitted from the vehicle. A sensor assembly is disposed in the housing, receives the exhaust emitted from the vehicle through the inlet, and determines the content of a plurality of different gases in the exhaust. A control system is disposed in the housing and is operatively coupled with the sensor assembly to regulate operations of the sensor assembly and to receive and interpret results of operations of the sensor assembly. A power supplying apparatus is disposed in the housing to deliver power throughout the system. The housing, and all components disposed in the housing have a combined weight of no greater than about five pounds.

Abstract: An improved self-cleaning oven (10) is provided having an assembly (12) to control the cleaning cycle time of the oven (10) depending upon the degree of oven contamination and soil present therein. The assembly (12) includes a measuring chamber (16) as well as a passageway (18) communicating the interior (14) of the oven (10) and the chamber (16). A smoke detector (32) (preferably an infrared smoke detector) is associated with the chamber (16) and is coupled with a controller (20) so as to measure a parameter of smoke passing through the chamber during at least a portion of the cleaning cycle. This parameter is then used to determine the proper duration of the cleaning cycle. In preferred forms, measuring chamber (16a) is equipped with an ambient air inlet (52) and outlet (54) so as to draw an ambient air stream through the chamber (16a) between the smoke detector (32) and the oven gas stream.

Abstract: The invention relates to a polymer composition comprising pH-sensitive fluorescent dyes, to an ionic strength-independent optical sensor for pH value determination that contains the composition in the form of a membrane on a transparent support material, and to an optical process, according to the fluorescence method, that renders possible highly accurate pH value determination independently of the ionic strength of the test solution. The process is especially suitable for the determination of the pH value of physiological solutions, especially for the determination of the pH value of blood.

Abstract: A light emitting diode 1 and a condenser lens 2 are arranged in an optical axis direction. In the light emitting diode 1, a cover 4 having a tip end lens 5 is attached to one side of a main unit base 9, a light emitting chip 6 is supported by a bonding wire 8 drawn out from the body base 9 inside the cover 4, and a reflector 7 is placed behind the light emitting chip 6. With respect to a first light source of the light emitting chip 6, the position where light which is forward reflected by the reflector 7 impinges on the tip end lens 5 is set as a virtual second light source 10, and the focal point of the condenser lens 2 is set at the position of or in the vicinity of the position of the second light source 10.

Abstract: A detector includes a sensor of an ambient condition. Outputs from the sensor are sampled at a predetermined rate when the outputs do not represent an alarm condition. The outputs are analyzed using pattern recognition techniques to determine if a predetermined profile, which precedes the presence of an alarm condition, is present. In the event that the profile is detected, the sample rate is increased along with associated sample value processing. The detector includes a programmable processor coupled to the sensor. The processor includes pattern recognition instructions for detecting the presence of the predetermined profile. The processor also includes instructions for altering the sampling rate in response to the detected presence of the profile. A second sensor can be incorporated to provide sample rate altering signals.

Abstract: An aspirated-type detector includes a housing with an internal ambient condition sensing region and a sensor carried therein. The housing is perforated with ambient atmosphere inflow ports. A fan or similar device lowers the pressure in the internal region thereby producing a positive inflow of adjacent, external ambient atmosphere into the sensing region. Alternatively, the fan can be operated to inject exterior ambient atmosphere into the sensing chamber under positive pressure. The fan can also be modularized. The detector can incorporate control circuitry for supervisory or signal processing purposes.

Abstract: The invention provides an improved process for determining the characteristics of dispersed particles. The process involves directing waves (acoustic or light) into a dispersion, and measuring the attenuation of the waves for particular frequencies to provide an attenuation spectrum. The measured attenuation spectrum is then compared to a set of theory-based calculated attenuation spectra to determine the particle size distribution corresponding to the measured attenuation spectrum. Unlike previous processes, the particle size distribution is capable of being accurately determined by a single inversion algorithm, thus eliminating burdensome steps of previous methods.

Abstract: This invention describes method and apparatus for protecting optical sensors in harsh industrial environments, particularly welding and machining. In a preferred embodiment, a sacrificial window is utilized which is replaced as needed. Numerous design features of such windows are disclosed. Other embodiments include protective baffles and other features.

Abstract: A driving unit generates a driving current corresponding to a light generation control signal CTL supplied from a light generation controlling unit. The driving current is supplied to an LED. Light emitted from the LED impinges on a light receiving circuit through a space of a monitoring area. The received light level of the light receiving circuit is converted into a received light level signal RLV in an A/D. The received light level signal RLV is supplied to a smoke detecting unit and the light generation controlling unit. The received light level signal RLV is monitored in a short period by the smoke detecting unit. When the received light level signal RLV is equal to or lower than an alarm level, an alarm signal ALM is output. The light generation controlling unit compares the received light level signal RLV with a reference level in a long period.

Abstract: An allergen particle detecting apparatus has a sample area through which environmental air is directed. A light beam is directed through the air sample so that portions of the beam will be scattered if any particles are present in the path of the beam. A beam blocking device on the opposite side of the air sample is arranged to block all light except light scattered in a predetermined angular range corresponding to a predetermined allergen particle size range. Light transmitted through the blocking device is detected by a light detector and an alarm output signal is produced if the detected amount of light is above a predetermined level.

Abstract: Method and apparatus for determining the opacity of exhaust plumes from moving emissions sources. In operation, a light source is activated at a time prior to the arrival of a diesel locomotive at a measurement point, by means of a track trigger switch or the Automatic Equipment Identification system, such that the opacity measurement is synchronized with the passage of an exhaust plume past the measurement point. A beam of light from the light source passes through the exhaust plume of the locomotive and is detected by a suitable detector, preferably a high-rate photodiode. The light beam is well-collimated and is preferably monochromatic, permitting the use of a narrowband pass filter to discriminate against background light. In order to span a double railroad track and provide a beam which is substantially stronger than background, the light source, preferably a diode laser, must provide a locally intense beam.

Abstract: A light beam is directed from a light source through an air sample so that portions of the beam will be scattered if any particles are present in the path of the beam. A beam blocking device on the opposite side of the air sample is arranged to block all light except light scattered in a predetermined angular range corresponding to a predetermined allergen particle size range. A light focusing lens in front of the light source is arranged to focus the unscattered part of the light beam onto the blocking device. Light transmitted through the blocking device is detected by a light detector and an alarm output signal is produced if the detected amount of light is above a predetermined level. The signal may be used to activate filtering or air conditioning devices.

Abstract: A vehicle gas analyzing system for testing gas content in exhaust emitted from a vehicle is disclosed. The vehicle gas analyzing system is of a size and weight to be held in a user's hands. The system includes a housing having outer dimensions no greater than about 12".times.8".times.3", and has an inlet receiving exhaust emitted from the vehicle. A sensor assembly is disposed in the housing, receives the exhaust emitted from the vehicle through the inlet, and determines the content of a plurality of different gases in the exhaust. A user interface is disposed on an outside surface of the housing, allowing a user to input instructions to the system and to perceive output from the system.

Abstract: An allergen particle detecting apparatus has a sample area through which environmental air is directed. A light beam is directed through the air sample so that portions of the beam will be scattered if any particles are present in the path of the beam. A beam blocking device on the opposite side of the air sample is arranged to block all light except light scattered in a predetermined angular range corresponding to a predetermined allergen particle size range. Light transmitted through the blocking device is detected by a light detector and an alarm output signal is produced if the detected amount of light is above a predetermined level.

Abstract: An allergen particle detecting apparatus has a sample area through which environmental air is directed. A light beam is directed through the air sample so that portions of the beam will be scattered if any particles are present in the path of the beam. A beam blocking device on the opposite side of the air sample is arranged to block all light except light scattered in a predetermined angular range corresponding to a predetermined allergen particle size range. Light transmitted through the blocking device is detected by a light detector and an alarm output signal is produced if the detected amount of light is above a predetermined level.

Abstract: An aspirated-type detector includes a housing with an internal ambient condition sensing region and a sensor carried therein. The housing is perforated with ambient atmosphere inflow ports. A fan or similar device lowers the pressure in the internal region thereby producing a positive inflow of adjacent, external ambient atmosphere into the sensing region. Alternatively, the fan can be operated to inject exterior ambient atmosphere into the sensing chamber under positive pressure. The fan can also be modularized. The detector can incorporate control circuitry for supervisory or signal processing purposes.

Abstract: A method and apparatus for monitoring a gaseous environment for the presence of cellular material capable of providing a measure of presence and/or numbers of cellular microorganisms, such as bacterial cells, in a large volume of air such as in a warehouse or production facility or in an open air location where bacterial presence is suspected. The method and apparatus are particularly suited for determining the likelihood of pathogenic material being present in an environment by batch or on-line measurement of cell numbers. On-line measurement provides continuous monitoring of an environment for presence of pathogens. The device includes a continuous flow luminometer preferably fed by a cyclone or high velocity virtual impactor and luminescence reagents which detect the amount of ATP or adenylate kinase present in a sample of air.

Abstract: A method for detecting dimethylaluminumhydride (DMAH) comprises sensing the aluminum oxide particles produced by the reaction of the DMAH with air (or with a small amount of oxygen). This is accomplished using a particle-sensing device, such as those commonly used to detect smoke, particularly an ionization-type detector.

Abstract: The smoke detector includes a light source (1), a measurement section (3) with a measuring receiver (5), a reference section (2) with a reference receiver (4), and an analyzer circuit (6) connected to the receivers. The receivers are of like construction and receive like amounts of radiation from the light source (1). A difference signal (.DELTA.I) formed from the current signal (I.sub.r) of the reference receiver and the current signal (I.sub.m) of the measuring receiver is fed to the analyzer circuit. A reference current (I.sub.k) is superimposed upon the current signal (I.sub.r) of the reference receiver, and the light source is connected to a control circuit and regulated by the control circuit for compensation of the reference current (I.sub.k) by the reference current signal (I.sub.r). The difference signal (.DELTA.I) is superimposed with a compensation signal (I.sub.k ') for zero compensation.

Abstract: The device for detecting the presence of smoke includes a dark chamber which receives the smoke to be detected, a source suitable for emitting into said chamber a light pencil made up of short duration pulses spaced apart from one another by identical much longer periods, a detector suitable for generating response signals associated with the smoke reflecting part of the successive light pulses, and means for comparing said signals with a threshold and for triggering an alarm in the event of said threshold being exceeded by a plurality of said successive signals. The device further comprises means for automatically increasing the frequency at which said pulses are emitted from the first occasion on which a signal exceeding said threshold is detected, the alarm then possibly being triggered, as a function of the signals generated by the detector in response to a plurality of successive pulses emitted at the higher frequency.

Abstract: A drive pulse for emitting and turning-off a light emitting element is output, the level difference or the level ratio between the light emission zero point detection signal from a light receiving element having received the light from the light emitting element and a putting-off zero point detection signal from the light receiving element when the light emitting element is put off is calculated, and the level difference or the level ratio is compared with a preset level to thereby determine the abnormality of the light emitting element, the light receiving element and a peripheral circuit. With this arrangement, even if the ratio of noise light occupied in the zero point output is reduced, whether detecting elements and the peripheral circuit are good or bad and whether the elements are abnormally polluted or not can be reliably tested without the effect of the dispersion of the detecting elements and the change of an ambient temperature, whereby the reliability of a smoke detector is improved.

Abstract: An apparatus is disclosed for continuously sampling, at a point downstream of the air cleaner, the normally clean air entering an air induction system of a diesel engine to produce a signal indicating a leakage malfunction condition in the air induction system by measuring dust/particulate matter. The disclosed apparatus includes an arrangement in the form of a sample collector assembly for obtaining a representative sample of leakage particulates within the diesel engine intake system, a measurement assembly for the quantification of the dust/particulates by optical methods, a signal conditioning assembly (200), a processor (300), and a remote annunciation assembly (400).

Abstract: This invention describes a method and apparatus for protecting optical sensors in harsh industrial environments, particularly welding and machining. In a preferred embodiment, a sacrificial window is utilized which is replaced as needed. Numerous design features of such windows are disclosed. Other embodiments include protective baffles and other features.

Abstract: A vacuum cleaner comprises a dust sensor having a light emitting device and a light receiving device which devices are provided at predetermined positions of a suction nozzle or a suction pipe in a condition that both devices are opposite to one another in a direction which crosses a dust suction direction by a predetermined angle. A spacer member is positioned at a predetermined accurately position the suction nozzle or the suction pipe by an engagement of with respect to a second projection member and a second concave section, and each device is positioned accurately relative to the spacer member by an engagement of a first concave section and a first projection member.

Abstract: A relative angle detecting system permitting a wider range of detectable angles and offering a small detection error by using polarization and a virtual reality providing system using the same are disclosed. The relative angle detecting system includes a light source having a given polarizing direction and a light reception unit in which a plurality of polarization filters having different polarizing directions other than 90 degree and a plurality of light-receiving devices for receiving light passing through the filters are incorporated, and a relative angle is calculated on the basis of a combination of strengths of output signals of the plurality of light-receiving devices.