Abstract: A raindrop detection apparatus includes a light emitting unit for emitting light to an inner side of a windshield, a light receiving unit for receiving the light reflected by an outer surface of the windshield, a first lens unit which is arranged between the windshield and the light emitting unit to convert the light from the light emitting unit into parallel light, and a second lens unit which is arranged between the windshield and the light receiving unit to converge the reflected light at the light receiving unit. The second lens unit is larger than a radial cross section of the reflected light. An amount of raindrop landed on the outer surface of the windshield is detected based on an intensity of the light received by the light receiving unit.

Abstract: It is an object to provide a vacuum apparatus capable of evaluating its cleanness precisely by surely monitoring particles including deposits readily detached from the apparatus, and a particle monitoring method and program employed therein, and a window member for particle monitoring. A semiconductor manufacturing apparatus 1000 includes a processing chamber 100 for performing a manufacturing processing on a wafer. A gas supply line for introducing a purge gas is connected to an upper portion of the processing chamber 100, a valve 120 being installed on the gas supply line. A rough pumping line 200 with a valve a is connected to a lower portion of the processing chamber 100. Installed on the rough pumping line 200 are a dry pump 220 for exhausting a gas in the processing chamber 100 and a particle monitoring unit 210 for monitoring particles between the valve a and the dry pump 220.

Abstract: An integrated spectral sensing engine featuring energy sources and detectors within a single package that includes sample interfacing optics and acquisition and processing electronics. The miniaturized sensor is optimized for specific laboratory and field-based measurements by integration into a handheld format. Design and fabrication components support high volume manufacturing. Spectral selectivity is provided by either continuous variable optical filters or filter matrix devices. The sensor's response covers the range from 200 nm to 25 ?m based on various solid-state detectors. The wavelength range can be extended by the use of filter-matrix devices. Measurement modes include transmittance/absorbance, turbidity (light scattering) and fluorescence (emission). On board data processing includes raw data acquisition, data massaging and the output of computed results. Sensor applications include water and environmental, food and beverage, chemical and petroleum, and medical analyses.

Abstract: A semiconductor manufacturing apparatus includes a processing chamber for performing a manufacturing processing on a wafer. A gas supply line for introducing a purge gas is connected to an upper portion of the processing chamber, a valve being installed on the gas supply line. A rough pumping line with a valve a is connected to a lower portion of the processing chamber. Installed on the rough pumping line are a dry pump for exhausting a gas in the processing chamber and a particle monitoring unit for monitoring particles between the valve a and the dry pump. In the semiconductor manufacturing apparatus, after the valve is opened, the purge gas is supplied to apply physical vibration due to shock wave in the processing chamber 100 so that deposits are detached therefrom to be monitored as particles.

Abstract: The invention relates to an optical cell for a separation chamber of a density centrifuge blood processing system for separating fluid components comprising an extraction chamber having a first external optical surface for transmitting at least a portion of an incident optical beam; and an extraction port having an axial bore for passing fluid components and a first external optical surface for transmitting at least a portion of the incident optical beam; wherein said first external optical surface of said extraction chamber and said first external optical surface of said extraction port are both positioned within the depth of field of a light collection element.

Abstract: A camera arrangement includes a camera, a light source, and a light-guide which are in an inside region separated from an outside region by a window. The camera and the light source are pointed at the window. The light-guide is between the camera and the window and between the light source and the window. The light-guide couples light incident to the window from the outside region towards a portion of the camera. The light-guide couples light from the light source into the window which is reflected at the interface between the window and the outside region and couples the reflected light towards another portion of the camera. The camera records an image indicative of the incident light from the outside region through the light-guide and records an intensity of the reflected light from the light source through the light-guide.

Abstract: An image input/output apparatus having a scanner unit disposed at an upper stage of an apparatus body and a liquid jet recording unit installed at a lower stage of the apparatus body includes a window which light passes through between the scanner unit and the liquid jet recording unit; an exposure controlling unit configured to control linear irradiation by a light source which illuminates an original platen when a maintenance mode of the recording unit is selected; and a luminous flux irradiation unit configured to irradiate a periphery of a liquid jet recording head in the above liquid jet recording unit with a luminous flux emitted from the light source passing through the window.

Abstract: A sensor device for detecting wetting on a windshield includes a light emission element for emitting a light, a first light reception element for receiving the light in a first light path that includes reflective redirection by the windshield, and a second light reception element for receiving the light in a second light path that does not include reflective redirection by the windshield. The sensor device uses a ratio of the amount of the received light by the first light reception element and the amount of the received light by the second light reception element to determine wetting on the windshield.

Abstract: The invention relates generally to methods of monitoring and controlling the processing of blood and blood samples, particularly the separation of blood and blood samples into its components. In one aspect, the invention relates to optical methods, devices and device components for measuring two-dimensional distributions of transmitted light intensities, scattered light intensities or both from a separation chamber of a density centrifuge. In embodiment, two-dimensional distributions of transmitted light intensities, scattered light intensities or both measured by the methods of the present invention comprise images of a separation chamber or component thereof, such as an optical cell of a separation chamber. In another aspect, the present invention relates to multifunctional monitoring and control systems for blood processing, particularly blood processing via density centrifugation.

Abstract: The present invention relates to a Drop Counter for counting a succession of falling liquid drops. The Drop Counter includes a light emitting diode for providing a light beam directed to a falling liquid drop. A photo diode sensor is positioned in side-by-side relation with the light emitting diode and detects reflected light from the falling liquid drop. The photo diode sensor provides an output signal when reflected light is detected and further includes a counter for receiving the output signal and counting the number of times the output signals are received.

Abstract: A liquid ejecting head is operable to eject liquid toward a target medium. A light emitter is operable to emit light. A light receiver is adapted to receive the light emitted from the light emitter, and operable to output a signal in accordance with an amount of the received light, thereby detecting a position of the liquid ejecting head. A transparent member is elongated in a first direction and disposed between the light emitter and the light receiver. A line pattern is provided with the transparent member so as to oppose the light emitter, and including light transmitting sections and light shielding sections which are alternately arranged in the first direction with a first pitch. Each of the light transmitting sections is adapted to allow the light emitted from the light emitter to pass through. Each of the light shielding sections is adapted to shield the light emitted from the light emitter.

Abstract: The invention is a precipitation sensor adapted to detect water upon an automotive glass and a method for its use. The precipitation sensor includes an optical emitter and a first mirror surface in optical communication with the optical emitter. The first mirror surface is adapted to reflect and collimate light emission from the optical emitter. The precipitation sensor also includes an optical receiver and a second mirror surface in optical communication with the optical receiver. The second mirror surface is adapted to focus collimated light upon the optical receiver. The precipitation sensor further includes an intermediate reflector in optical communication with the first mirror surface and with the second mirror surface.

Abstract: Methods and apparatus for evaluating the quality of a sample of a product, an ingredient, an environment or process by measuring multiple parameters thereof, including light emitted from a reacting sample containing ATP, ADP, alkaline phosphatase or other parameters such as pH, temperature, conductivity, reduction potential, dissolved gases, specific ions, and microbiological count. The apparatus comprises an integrated sample testing device used to collect a sample, mix reagents, react the sample, and collect it in a measurement chamber. The apparatus also comprises an instrument having a photon detection assembly for use with the sample testing device. The instrument can also comprise one or more sensing probes and a communication port to facilitate data collection, transfer and analysis.

Abstract: A sensor device for detecting wetting on a windshield includes a light emission element for emitting a light, a first light reception element for receiving the light in a first light path that includes reflective redirection by the windshield, and a second light reception element for receiving the light in a second light path that does not include reflective redirection by the windshield. The sensor device uses a ratio of the amount of the received light by the first light reception element and the amount of the received light by the second light reception element to determine wetting on the windshield.

Abstract: A biological aerosol detector is provided. The biological aerosol detector uses a semiconductor optical source with an ultraviolet emission band to excite biological molecules in an aerosol sample. Filtering optics are configured to attenuate radiation from a secondary emission band of the optical source to prevent false signals due to scattering of secondary emission band radiation from non-biological molecules. An intake/exhaust manifold that includes an intake pipe that fits within a concentric exhaust pipe is also provided. The intake/exhaust manifold planarizes the flow of the sampled aerosol to maximize the time of irradiation. An electrostatic sampling grid is also provided to selectively draw biological molecules having a net charge into the optical chamber.

Abstract: The invention concerns a method for detecting gas bubbles in a liquid adapted to a device comprising a light source, a light detector and a data controlling and processing unit connected to a client system comprising the following steps: emitting light from the light source, acquiring successive measurements of the light intensity sensed by the light detector and calculating a variation between two successive measurements of said light intensity. In accordance with a first embodiment of the invention, the method further comprises a step which consists in comparing the variation between two successive measurements of light intensity to a threshold S. Advantageously, a warning counter is incremented by a value A when variation between two successive measurements is higher than the threshold S and decremented by a value B in the opposite case. A proportion of bubbles higher than a maximum authorized rate is detected when said warning counter exceeds a warning value C.

Abstract: A gas flux measuring device measures a region, such as a forest, as a measuring object with no influence by concomitants and with high responsiveness and excellent measuring stability. The device includes a laser beam source, laser output controller, wavelength modulation controller, first light receiver, first direct current component detector, first wavelength modulation demodulator, optical system, reference cell, second light receiver, second direct current component detector, second wavelength modulation demodulator, third wavelength modulation demodulator, analyzer, adder, temperature measurement and pressure measurement. A flow velocity measuring device directly measures horizontal 2-directional flow velocity components and a vertical directional flow velocity component of a gas flow in the measuring region and puts out these measurement signals into the analyzer.

Abstract: An improved elemental mercury analyzer utilizes a fluorescence assembly in combination with a fluorescence quenching reduction mechanism to detect the concentration of elemental mercury within an emission gas sample, via fluorescence of the mercury within the gas sample, while minimizing fluorescence quenching of the gas sample. In one arrangement, the analyzer contains the emission gas sample under a vacuum or negative pressure while detecting fluorescence of the elemental mercury within the emission gas sample. By performing fluorescence detection of the emission gas sample at reduced pressure relative to the pressure of the as-sampled emission gas, the analyzer reduces the number of particle collisions within the emission gas sample over a certain period of time. Such collisional deactivation, and/or the addition of oxygen depleted gas such as nitrogen to the gas sample, reduces fluorescence quenching of the emission gas sample, improving accuracy of detection of mercury.

Abstract: An optical device is described that include: a photoemitter for emitting light, a mounting unit for installing a transparent container accommodating a sample to be subjected to detection, a photoreceptor for receiving the light emitted by a photoemitter and transmitted through the transparent container installed in the mounting unit, a first member disposed between the transparent container and the photoreceptor and having a first pinhole through which passes the light transmitted through the transparent container, and a second member disposed between the first member and the photoreceptor and having a second pinhole through which passes the transmitted light that has passed through the first pinhole.

Abstract: An exterior element sensor can include an optical element mounted on a window. The optical element can include a cylindrical lens having both ends shaped spherically and a central portion that exerts little or no influence on exterior element detection (such as rain, snow, ice, water, liquid, debris, or other materials) when visible light transmits therethrough. In addition, infrared or other light can be used to detect exterior elements located on the window. A black filter can be employed, if desired, which blocks visible light and transmits infrared light therethrough to separate visible light from infrared light, thereby allowing the exterior element sensor to be used together with an exterior light sensor without losing accuracy.

Abstract: A device for measuring a mass flow rate of a flow of particulate material which moves in a predetermined direction. The device includes a weighing cell, a first apparatus, a second apparatus, and a third apparatus. The weighing cell includes a tubular wall and is disposed to be passed through by a flow of particulate material. The first apparatus weighs the weighing cell and the quantity of particulate material contained in the weighing cell and produces a first signal. The second apparatus measures the speed of flow of the particulate material which flows through the weighing cell and produces a second signal. The third apparatus calculates the bulk density of the particulate material, calculates the mass flow rate of particulate material which flows through the weighing cell, and produces a third signal representing the mass flow rate of particulate material which flows through the weighing cell.

Abstract: An apparatus measures a fluid level in a container. A light source emits a light beam. A light sensor can sense the light beam. An optical conduit is arranged in a container for holding fluid. The optical conduit is arranged between the light source and the light sensor along a path of the light beam, such that at least one part of the light beam passes through the optical conduit, and at least an other part of the light beam passes through the fluid when the container holds the fluid. The sensor senses the light beam when a level of the fluid coincides with the one part of the light beam passing through the optical conduit, and the sensor does not sense the light beam when the level of the fluid coincides with the other part of the light beam passing through the fluid due to internal reflection at the fluid level.

Abstract: Methods and apparatus for improving the resolution of an electronic imaging device having an array of pixels. Sub-pixel dimension movements between an object and the array of pixels are made, and an image is formed at each position. Resulting shifted images are combined to yield an effective resolution corresponding to an array having smaller pixels. Such methods and apparatus allow optical systems with existing pixel devices to form effective images of smaller feature sizes.

Abstract: A method for reducing false detects may include emitting an infrared light beam from a primary emitter to a primary monitor detector, measuring a first voltage value using a primary receive detector and setting a primary smoke alarm flag corresponding to a primary channel if the first voltage value is above a first threshold value. The method may also include measuring a second voltage value using a secondary receive detector, setting a secondary smoke alarm flag corresponding to a secondary channel if the second voltage value is above a second threshold value and setting an alarm indicating a smoke condition if the primary smoke alarm flag and the secondary smoke alarm flag are set.

Abstract: A raindrop sensor includes a light-emitting element, a light-receiving element and a light guide body. The light-emitting element and the light-receiving element face a transparent panel. The light guide body, which is mounted on the transparent panel, includes an input lens, an input side dividing surface, an output lens and an output side dividing surface. The input lens collimates light emitted by the light-emitting element to form an input side collimated light beam. The output lens receives the collimated light beam, which is collimated by the input lens and is reflected by a reference surface of the transparent panel, to which the raindrop attaches. The output lens converges the reflected collimated light beam toward the light-receiving element. An intersection between an imaginary extension of the input side dividing surface and an imaginary extension of the output side dividing surface is located on the reference surface of the transparent panel.

Abstract: The invention herein provides for the detection of certain calcium containing endospores, and particularly pertains to the detection of bacillus anthracis by first chelating calcium ions of said endospores and then reacting the chelated calcium ions with aequorin to generate a light pulse which can then be detected by a standard liquid scintillation spectrometer.

Abstract: Multiplexer for electromagnetic radiation, e.g. UV-light, in which a single electromagnetic radiation source (203) and a single electromagnetic radiation detector (223) are connectable in turn to a plurality of sample-containing units (207(a)-207(n)). The multiplexer comprises a sled (253) movable in relation to a fixed base (255) by an actuator (281).

Abstract: Some embodiments of the invention provide an apparatus for measuring active fluorescence in liquid samples by using solid-state components. The use of solid-state devices dramatically lowers the cost, size, and power consumption of active fluorescence while improving the ruggedness and reliability. The smaller size of the solid-state devices allows them to be placed very close to the sample. This maximizes the amount of light the sample receives from the light sources and allows efficient collection of the resulting emitted light using simple and low cost optical components.

Abstract: An optoelectronic sensor for sensing wetting of a windshield includes a first circuit, and a radiation emitter and a radiation detector both arranged on the first circuit to emit radiation toward the windshield and to detect radiation reflected from the windshield. Beam shapers parallelize the emitted radiation toward the windshield and focus radiation reflected from the windshield toward the detector. A coupling element couples the emitted radiation into the windshield and couples the reflected radiation out of the windshield. A structural element is arranged between the lens holder and the coupling element. The structural element may have retaining elements for positioning a second circuit arranged between the lens holder and the structural element relative to the windshield. The structural element may have support elements for adjustably positioning the lens holder and thereby the beam shapers relative to the first circuit and the windshield.

Abstract: In a method for controlling an orienting/positioning system, the orienting system comprises at least one sensor means, an external motion detection device for detecting an externally-caused motion in the environment of the sensor means and actuator means for controlling an orienting and/or positioning action of the sensor means.

Abstract: An apparatus for document processing comprises an optical sensor including a light source, a light detector and an optical element. The optical sensor is adapted so that, during operation of the apparatus, at least a first portion of light from the source that enters the optical element travels along paths in the optical element so as to be re-directed by total internal reflection toward the detector and wherein the total internal reflection is maintained when the optical element is wet. Signals form the optical sensor may be used to determine, for example, the state of a document storage cassette or the location of a document with respect to the cassette.

Abstract: Two different kinds of fluids are sent to a flow path for measurement in which a plurality of detection sections are provided, transit time of consecutive fluid, following preceding fluid, at each detection unit is detected, and a flow speed of the fluid is found from time required for the consecutive fluid to move between the plurality of detection sections. The present invention provides a measuring apparatus which measures the flow speed and a rate of flow in the flow path with suppressing an influence from the external to the fluid thereby, and a measuring method using the measuring apparatus.

Abstract: An optical transducer for determining the presence or absence of liquid or the like in a reservoir includes a housing with a hollow interior and an optical probe that extends through the housing. The optical probe has a central axis, a proximal end positioned in the hollow interior and a distal end positioned outside of the housing. The distal end has first and second measurement surfaces that intersect at a transverse edge. The transverse edge extends at an acute angle with respect to the central axis. A light source is arranged for projecting radiant energy into the optical probe toward the distal end. A photosensor is arranged for detecting radiant energy reflected from the distal end to thereby detect the presence and absence of liquid on the optical probe.

Abstract: Systems and methods for fluid level detection are disclosed. In one embodiment, a sensor assembly includes at least one optical fiber adapted to at least one of transmit and receive an optical signal, and a moveable float member. The float member is adapted to move in a first direction as the fluid level increases and in a second direction as the fluid level decreases. The float member blocks the optical signal at a first value of the fluid level, and allows the optical signal to pass at a second value of the fluid level. The presence or absence of the optical signal is detected to determine the level of fluid.

Abstract: A photometer device including an inlet passage for receiving a fluid such as an aerosol at a specified flow rate, an outlet passage separated from the inlet passage by a gap, and a radiation passage across the gap. The flow rate and the significant dimension of the inlet passage are set to produce a laminar flow of the aerosol. The gap and the significant dimension of the outlet passage are set to maintain a laminar flow of the aerosol across the gap to prevent contamination of the radiation passage.

Abstract: A soil moisture sensor uses a non-collimated light source and a photosensor, respectively, mounted at the foci of a transparent ellipsoidal plastic body. The dimensions of the body are such that emitted light rays are internally reflected toward the photosensor at the surface of the ellipsoid if the surface is dry, but refracted outwardly of the body when the surface is wet. The amount of light reflected onto the photosensor is thus a measure of the amount of moisture at the surface of the sensor. Direct illumination of the photosensor by the light source is prevented either by interposing opaque electronic components between them on a circuit board, or by taking advantage of light source characteristics to minimize the amount of transmitted light. If a circuit board is used, it is completely encapsulated against moisture penetration by fixing it in a carrier and molding the body around and onto the carrier to form a monolithic unit with the carrier and circuit board.

Abstract: An optical switch having a housing, a light source and a light detector. The light source and light detector are located remote from the housing. The light source is connected to the housing with a first light guide, and the light detector is connected to the housing with a second light guide. The first and second light guide cables have distal ends positioned through the housing and are optically aligned but separated by a gap. The switch includes a device to interrupt a light beam that is usually adapted to removably occupy the gap.

Abstract: A system for detecting liquid flow from a nozzle in a semiconductor processing device includes a first fiber optic sensor, a second fiber optic sensor, and an amp. The first fiber optic sensor and second fiber optic sensor are located on opposite sides of at least one nozzle. The first fiber optic sensor transmits light, and the second fiber optic sensor receives more of the light when the nozzle is not dispensing liquid than when the nozzle is dispensing liquid. The amp is coupled to the first fiber optic sensor and second fiber optic sensor. The amp indicates whether the nozzle is dispensing liquid according to an amount of the light received at the second fiber optic sensor.

Abstract: An image processing apparatus uses a camera to pick up images of an image pickup target illuminated by a transmission type illumination, via optical filters, and then allows a spectral characteristic estimating section and a pigment amount estimating section to calculate a physical amount relating to the image pickup target for each pixel of the image pickup target, on the basis of the picked-up multiple band images. On this occasion, the image processing apparatus uses the optical filters the number of which is equal to the number of independent components of the calculated physical amount.

Abstract: One or more optical signals (wherein at least some of a plurality of optical signals are at different angles of travel with respect to one another and are directed towards an area comprising a movable barrier-controlled point of passage) create reflections when striking passageway boundaries as correspond to a given movable barrier. Obstacles in the pathway also give rise to reflections. By determining a time-of-flight for such reflections, one can detect a likely presence of an obstacle in such a pathway. Pursuant to one approach, such time-of-flight information can further provide information regarding a likely size of such an obstacle.

Abstract: A method for the detection and signaling of smoke by means of an optical assembly in a detector casing, the optical assembly including at least one optical transmitter element and at least one optical receiver element, and which emits a reception signal which is representative of the incident amount of light. An electronic evaluation device compares the reception signal to a setpoint and an alarm signal is generated when the reception signal reaches the predetermined threshold value. The temperature is measured on or in the detector casing and the temporal characteristic of the temperature is correlated with the temporal characteristic of the reception signal of the optical receiver element and a dew film signal is generated when the rise in the reception signal is correlated to a rise in temperature.

Abstract: The present invention aims at attaining a liquid surface level detecting apparatus, which can be used in various detection targets and usage environments without selecting a detection target, can efficiently irradiate a light to a liquid surface level detecting unit and detect a variation in a light reception amount of a light receiving means at a high sensibility, and can be excellent in durability, easy to manufacture, and be actually used. By placing a light shielding means 14 so as not to directly irradiate the light from a light emitting means 12 to a light receiving means 13, the light from the light emitting means is scattered by an optically scattering means 16, and a part of that scattering light is radiated to an outside by the liquid surface level detecting unit on a light radiating means (an optically transmitting member) 11.

Abstract: Methods and apparatus for improving the resolution of an electronic imaging device having an array of pixels. Sub-pixel dimension movements between an object and the array of pixels are made, and an image is formed at each position. Resulting shifted images are combined to yield an effective resolution corresponding to an array having smaller pixels. Such methods and apparatus allow optical systems with existing pixel devices to form effective images of smaller feature sizes.

Abstract: A flowmeter has a variable area, vertically-oriented duct through which flows fluid whose flow rate is to be determined. A float in the duct assumes a position in the duct that depends on the flow rate of fluid in the duct. A window is located at an end of the duct in alignment with a longitudinal axis of the duct. A transducer unit projects a light beam through the window and along the axis toward the float. The transducer includes a light sensor that detects light returned by the float by reflection or some other mechanism to the transducer unit. The intensity or other characteristic of the returned light indicates the position of the float in the duct, from which the fluid flow rate may be determined.

Abstract: A soil moisture sensor has a cylindrical body of transparent cyclic olefin polymer (COC). A pair of axially spaced cavities tapered toward each other are formed in the body. A light source is placed in one of the cavities, and a light sensor is placed in the other. The walls of the cavities are so curved that divergent light rays from the light source are refracted at the cavity-body interface into parallelism, and that reflected parallel rays are refracted at the body-cavity interface so as to focus on the light sensor. The parallel rays coming from the light source are reflected or refracted at the outer surface of the body, depending upon whether the ambient environment of the sensor is dry or wet.

Abstract: A measuring apparatus includes a sensor well unit having a plurality of sample wells, which are formed in a dielectric block and a thin film layer provided on the inner bottom surface of each sample well. A light beam projector causes a plurality of light beams to impinge upon the interfaces of the inner bottom surfaces of one-dimensionally arranged sample wells out of the plurality of sample wells and the thin film layers at various angles of incidence so that total internal reflection conditions are satisfied at each of the interfaces, and the light beams reflected at the respective interfaces are received by a photodetector. A longitudinal tilt measuring system measures a longitudinal tilt of the interface from a predetermined reference position, and a corrected measured value corrected according to the longitudinal tilt measured by the longitudinal tilt measuring system is obtained.

Abstract: A method for creating large numbers of high-quality optical traps in arbitrary three-dimensional configurations and dynamically reconfiguring the traps under computer control. The method uses computer-generated diffractive optical elements to convert one or more optical tweezers into one or more optical vortices. The method involves combining the optical vortex technique with the holographic optical tweezer technique to create multiple optical vortices in arbitrary configurations. The method also involves employing the rotation induced in trapped particles by optical vortices to assemble clusters of particles into functional micromachines, to drive previously assembled micromachines, to pump fluids through microfluidics channels, to control flows of fluids through microfluidics channels, to mix fluids within microfluidics channels, to transport particles, to sort particles and to perform other related manipulations and transformations on matter over length scales.

Abstract: A compact particle sensor for detecting suspended particles includes a housing, a light source, a light receiver and a plurality of optical elements. The housing provides a test chamber and includes at least one opening for admitting particles into the test chamber, while simultaneously substantially preventing outside light from entering the test chamber. The light source is positioned for supplying a light beam within the test chamber. The plurality of optical elements are positioned to direct the light beam from the light source to the receiver, which is positioned to receive the light beam supplied by the light source.

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 content detecting apparatus uses a signal from a light-receiving part receiving light projected from a light emitting part to detect ink in an ink cartridge. The light-emitting part and the light-receiving part are arranged with differing optical axes. The ink cartridge has reflecting parts for reflecting projected light from the light-emitting part so the projected light reaches the light-receiving part when remaining content is present when the ink cartridge is properly set and with an inclined interface located in a path along which projected light from the light-emitting part reaches the light-receiving part, for switching between permeation and reflection according to the presence and/or absence of remaining content. The inclined interface is permeated along the path with projected light form the light-emitting part when remaining content is present and reflects projected light from the light-emitting part out of the path when remaining content is absent.