Abstract:
An infrared sensor IC and an infrared sensor, which are extremely small and are not easily affected by electromagnetic noise and thermal fluctuation, and a manufacturing method thereof are provided. A compound semiconductor that has a small device resistance and a large electron mobility is used for a sensor (2), and then, the compound semiconductor sensor (2) and an integrated circuit (3), which processes an electrical signal output by the compound semiconductor sensor (2) and performs an operation, are arranged in a single package using hybrid formation. In this manner, an infrared sensor IC that can be operated at room temperature can be provided by a microminiature and simple package that is not conventionally produced.
Abstract:
The present invention relates to a method and system of array imaging that extends or maximizes the longevity of the sensor array by minimizing the effects of photobleaching. The imaging system has a light source, a variable exposure aperture, and a variable filter system. The system extends the longevity of sensors by (1) using the variable exposure aperture to selectively expose sections of the sensor array containing representative numbers of each type of sensor, and/or (2) using the variable filter system to control the intensity of the excitation light, providing only the intensity required to induce the appropriate excitation and increasing that intensity over time as necessary to counteract the effects of photobleaching.
Abstract:
Method for limiting amount of radiation impinging on a radiation-sensitive detector device by directing radiation toward the detector, permitting the radiation to impinge upon the detector device when the radiation is below a predetermined threshold, and utilizing radiation having wavelengths different from signals of interest to initiate limiting of the radiation impinging upon the detector when the predetermined threshold is exceeded. The optical limiter includes an IR limiting layer pair selected so that energy from visible and near infrared radiation activates the optical limiter. The limiting layer pair may includes a layer closer to the source of radiation of e.g. vanadium dioxide, vanadium sesquioxide, or germanium crystal and a layer further from the source of radiation of e.g. chalcogenide glass, germanium crystal, or sodium chloride crystal.
Abstract:
An apparatus and appertaining method is provided for systems having an illumination transmitter and an illumination receiver in which the illumination receiver receives radiation emitted by the illumination transmitter but also receives ambient radiation that adds unwanted noise to the signal received by the receiver. Advantageously, the illumination transmitter transmits a pulsed signal having an on state and an off state. An on state sample and hold circuit samples the signal when the receiver is receiving both the transmitter signal and ambient radiation, and an off state sample and hold circuit samples the signal when the receiver is only receiving the ambient radiation. The off state signal is subtracted from the on state signal, thereby providing an output that is free of the ambient radiation signal.
Abstract:
An imaging system for use in a vehicle headlamp control system includes an opening, an image sensor, a red lens blocking red complement light between the opening and the image sensor, and a red complement lens blocking red light between the opening and the image sensor. Each lens focuses light onto a different subwindow of the image sensor. The imaging system allows processing and control logic to detect the presence of headlamps on oncoming vehicles and tail lights on vehicles approached from the rear for the purpose of controlling headlamps. A light sampling lens may be used to redirect light rays from an arc spanning above the vehicle to in front of the vehicle into substantially horizontal rays. The light sampling lens is imaged by the image sensor to produce an indication of light intensity at various elevations. The processing and control logic uses the light intensity to determine whether headlamps should be turned on or off. A shutter may be used to protect elements of the imaging system from excessive light exposure.
Abstract:
An ultraviolet sensor includes a substrate; a diamond layer, placed on the substrate, functioning as a detector; and at least one pair of surface electrodes arranged on the diamond layer. The diamond layer has a detecting region present at the surface thereof, the detecting region has at least one sub-region exposed from the surface electrodes, and the sub-region has a covering layer, made of oxide or fluoride, lying thereon. A method for manufacturing the ultraviolet sensor includes a step of forming a diamond layer, functioning as a detector, on a substrate; a step of forming at least one pair of surface electrodes on the diamond layer; and a step of forming a covering layer, made of oxide or fluoride, on at least one sub-region of a detecting region present at the surface of the diamond layer, the sub-region being exposed from the surface electrodes.
Abstract:
A sensor circuit for detecting the occurrence of welding is disclosed. The sensor circuit uses a phototransistor operative to receive a light input and produce an output representative thereof. A resistor is coupled between the phototransistor's base and emitter to control the phototransistor's response to low intensity and high intensity light. An amplifier may be coupled to the output of the phototransistor so as to provide a gain for the output of the phototransistor; and feedback means may coupled to the phototransistor to bias the phototransistor, the feedback means comprising a resistor capacitor circuit for following the output of the phototransistor, a feedback transistor to provide a feedback signal to the phototransistor, and a resistor coupled between the base and the emitter of the phototransistor. Preferably the phototransistor is a planar phototransistor having a surface mount. The sensor circuit may also be used in an auto-darkening eye protection device, such as a welding helmet or the like, that delivers a drive signal to a shutter assembly upon the detection of welding, the drive signal being operative to drive the shutter assembly to a darkened, protective state. A solar cell may be used to reduce the circuit's power consumption by powering various circuit components only when the welding helmet is exposed to light. The present invention provides reduced power consumption, improved attenuation of low intensity light signals, a sharp rise time from the phototransistor in response to high intensity light, and allows implementation into a smaller sleeker eye protection device.
Abstract:
A sensor circuit for detecting the occurrence of welding is disclosed. The sensor circuit uses a phototransistor operative to receive a light input and produce an output representative thereof. A resistor is coupled between the phototransistor's base and emitter to control the phototransistor's response to low intensity and high intensity light. An amplifier may be coupled to the output of the phototransistor so as to provide a gain for the output of the phototransistor; and feedback means may coupled to the phototransistor to bias the phototransistor, the feedback means comprising a resistor capacitor circuit for following the output of the phototransistor, a feedback transistor to provide a feedback signal to the phototransistor, and a resistor coupled between the base and the emitter of the phototransistor. Preferably the phototransistor is a planar phototransistor having a surface mount. The sensor circuit may also be used in an auto-darkening eye protection device, such as a welding helmet or the like, that delivers a drive signal to a shutter assembly upon the detection of welding, the drive signal being operative to drive the shutter assembly to a darkened, protective state. A solar cell may be used to reduce the circuit's power consumption by powering various circuit components only when the welding helmet is exposed to light. The present invention provides reduced power consumption, improved attenuation of low intensity light signals, a sharp rise time from the phototransistor in response to high intensity light, and allows implementation into a smaller sleeker eye protection device.
Abstract:
An imaging system for use in a vehicle headlamp control system including an opening, an image sensor, a red lens blocking red complement light between the opening and the image sensor, and a red complement lens blocking red light between the opening and the image sensor. Each lens focuses light onto a different subwindow of the image sensor. The imaging system allows processing and control logic to detect the presence of headlamps on oncoming vehicles and tail lights on vehicles approached from the rear for the purpose of controlling headlamps. A light sampling lens may be used to redirect light rays from an arc spanning above the vehicle to in front of the vehicle into substantially horizontal rays. The light sampling lens is imaged by the image sensor to produce an indication of light intensity at various elevations. The processing and control logic uses the light intensity to determine whether headlamps should be turned on or off. A shutter may be used to protect elements of the imaging system from excessive light exposure.
Abstract:
A UV sensor design which virtually eliminates solarization effects on optical components and photodetector and is effective for both broad area and collimated light sources. The sensor design reduces the number of photons striking a unit area of any of the materials in the light path sensitive to UV light to a level which does not produce appreciable solarization over very long periods of time. The UV sensor has as the first optical element in the viewing path a UV transmitting, extremely low solarization window. The back surface of this window is frosted to produce some diffusion of the UV rays. A small metal disc with a very small aperture is the next optical element and reduces the total amount of energy admitted to the optical measurement system. A second frosted UV transmitting, extremely low solarization window further diffuses the light beam passing through the aperture. The UV light from this second window travels toward to two UV filters and is further dispersed to produce low intensity level UV light which impinges on a silicon photodetector.