Abstract: Disclosed is a photodetector with a multilayer filter. A light-receiving substrate is mounted on a recessed portion of a ceramic stem. An electrode pad is formed on a P-type layer of the light-receiving substrate while another electrode pad is formed on an N-type layer of the light-receiving substrate. An optical multilayer filter is formed on the light-receiving substrate except the regions of the electrode pads. Further, an epoxy transparent resin is poured into the recessed portion of the stem and then cured, so that a resin portion to cover the light-receiving substrate is formed. The optical multilayer filter is formed of amorphous low refractive index films made of SiC.sub.2 and amorphous high refractive index films made of TiO.sub.2. The amorphous high and low refractive index films are alternately stacked.

Abstract: A scanning device and method for forming a scanned electronic image include using navigation information that is acquired along with image data, and then rectifying the image data based upon the navigation and image information. The navigation information is obtained in frames. The differences between consecutive frames are detected and accumulated, and this accumulated displacement value is representative of a position of the scanning device relative to a reference. The image data is then positioned-tagged using the position data obtained from the accumulated displacement value. To avoid the accumulation of errors, the accumulated displacement value obtained from consecutive frames is updated by comparing a current frame with a much earlier frame stored in memory and using the resulting difference as the displacement from the earlier frame. These larger displacement steps are then accumulated to determine the relative position of the scanning device.

Abstract: Signal charges are photoelectrically generated by a plurality of photodiodes, transferred through a transfer register to a charge detection capacitance and sensed through a floating junction, as a potential change of the charge detection capacitance to be amplified and output at an output amplifier composed of a plurality of stages of driver transistors, in which a field insulation film of a first stage driver transistor is formed, under a gate electrode, with a trapezoidal region left so that the gate electrode has a width thereof varied to be wider at a source end than at a drain end, permitting an increased reduction of the charge detection capacitance.

Abstract: One embodiment of an apparatus for checking semiconductor wafers includes a receiver for a semiconductor wafer to be checked. A light illuminates the wafer. A hemispherical hood has a surface and a hemispherical region defining an interior inside the hemispherical region. A further hood is disposed in the vicinity of the light. A camera is disposed at the hemispherical hood and has a lens looking into the interior inside the hemispherical hood. A evaluator is connected to the camera for controlling the camera and receiving, buffer-storing, processing and outputing data transmitted by the camera. Another embodiment includes a first light directly illuminates the wafer with light of a first color and a second light indirectly illuminates the wafer with light of a second color being complementary to the first color. A surface of the hood is of the second color.

Abstract: A method and device for counting and characterizing defects on a photographic support includes inspecting the support with an optical density measuring device. The defects present on the support are then detected, counted and then characterized.

Abstract: A fiber-optic sensor composed of elements made of shape-memory alloy which, in one of their memorized shapes, impose a stress on the optical fiber, which stress is easy to locate with an interferometer. The multisensor configuration is thus easily reconfigurable.

Abstract: An optical waveguide sensor arrangement for sensing at least one physical parameter is provided. This arrangement comprises an optical waveguide having guided modes, lossy non-guided modes, and a long period grating coupling the guided modes to the lossy non-guided modes wherein the long period grating produces a wavelength transmission spectrum functionally dependent on the physical parameter sensed. A source means provides light to the optical waveguide sensor and an optoelectronic detector, which is positioned in an operable relationship to the optical waveguide sensor, detects light transmitted through the optical waveguide sensor. Lastly, a processing means is attached to the optoelectronic detector for correlating the wavelength transmission spectrum with a numerical value for the physical parameter sensed. The physical parameters sensed by the optical waveguide sensor include: temperature, strain, shape, refractive index and corrosion.

Abstract: A multi-axis light beam type sensor with a simple fail-safe sensor system which stops when the sensor system is abnormal (logic value "0") is provided. The construction is such that scanning output signals for synchronously driving respective light emitting elements (LD) and light receiving elements (PD) positioned facing each other are generated using shift registers. A normal or abnormal condition of the scanning output signals is judged based on an output of the light transmission side shift register (5), using an addition operation in a scanning output signal checking circuit (9). Moreover, coincidence or non coincidence of last stage outputs of the respective shift registers of the light transmission and light reception sides, is determined by a coincidence detecting circuit (10).

Abstract: An inexpensive and easily adjustable distance measuring apparatus judges whether an object is located at a far distance or at a near distance relative to a certain set distance. The distance measuring apparatus comprises an oscillator for generating pulses, a light emitting element for emitting light for a predetermined time in synchronization with the pulses generated by the oscillator, a plurality of light receiving elements disposed adjacent to each other to receive reflected light emitted by the light emitting element and reflected by an object whose distance is to be measured, a plurality of delay circuits connected to respective ones of the light receiving elements, and a phase discriminating circuit for comparing the phases of the output signals of each of the delay circuits.

Abstract: An optical detector for determining the wavelength of an optical signal iudes a semiconductor material in the path of the optical signal having a bandgap less than the optical signal. A conductive layer is positioned on the semiconductor material and a plurality of conductive pads are also positioned on the semiconductor material to delineate individual photodetectors. The pads have a common node established by the conductive layer. The optical detector produces a plurality of photocurrents between the pads and the conductive layer in response to the optical signal which photocurrents can be measured and compared to determine the wavelength of the optical signal. A system for determining the wavelength of the optical signal includes a plurality of optical detectors numbered 1 to n positioned sequentially in the path of the optical signal. The detectors produce photocurrents which are converted into digital signals. A microprocessor receives the digital signals and determines a ratio therebetween.

Abstract: A fiber optic sensor is also disclosed for measuring or detecting the prece of an environmental field condition such as under-water acoustic perturbations. The sensor includes a force transfer transducer, which is enclosed within a shell, with a pressure equalizer for equalizing the interior and exterior shell pressures. An optical fiber is coiled about the transducer. An optical detector detects stress or strain in the optical fiber, resulting from external perturbations. The sensor is able to operate at various depths or altitudes. Pressure equalization enables the isolation of dynamic external perturbations from other pressure variations. For this purpose, a pressure equalizing valve may be used to allow the equalization of slow changes in static pressures, and the detection of higher frequency perturbations which might emanate from a target source.

Abstract: A refracting plate is installed in the center of an actuator provided with a gimbaling mechanism element, which includes rotation supporting portions. A pair of voice coil motors are provided for each of the X- and the Y-axis in order to incline the refracting plate about the respective rotation supporting portions, and their own bobbins press the middle parts of the respective sides of the gimbaling mechanism element.

Abstract: The present disclosure teaches a method and apparatus for use in stabilizing images. The invention operates to sense the position of the image to be stabilized, compare the position of the image to a reference to determine a displacement value responsive thereto and change a correction element located in the conveyance path of the image in response to the displacement value to cause a compensating displacement of the image.

Abstract: A device and method for detecting the location of an object in a surface employs a first plurality of light sources disposed along a first row adjacent the surface. A first plurality of light detectors is disposed along a second row adjacent the surface and spaced apart from the first row. Each detector outputs an analog signal representative of the intensity of light being detected. A control means causes each of the light sources to be illuminated at a different time. A calculating means determines the location of the object based on the analog signals from the detectors. The calculating means determines the location of the object by determining coordinates of a first line and a second line, the first line extending from a first light source to a centerpoint of a first shadow cast upon a first neighboring group of the detectors and the second line extending from a second light source to a centerpoint of a second shadow cast upon a second neighboring group of the detectors.

Abstract: This invention features a sensing system and a method for dispensing financial and retail receipts from a receipt-printing machine. The sensing system of this invention can use any one of a myriad of typical supply rolls having a media strip (usually paper) that has black marks periodically located at given intervals along its edge. The sensing system usually has a light-emitting diode (LED) and a photo-transistor. The light from the LED is directed on the supply roll, where, as the paper is advanced, it is reflected to the photo-transistor. When a black mark comes into the range of the LED, the light from the LED is absorbed and not reflected to the photo-transistor. The printing machine then stops advancing the paper, and cuts it to form a receipt of adequate length. The invention utilizes a microprocessor that has a pulse width modulator (PWM) for providing a square wave output to a digital-to-analog (D/A) converter. A program of the microprocessor controls the frequency and the duty cycle of the PWM.

Abstract: A projection exposure apparatus comprises a projection optical system for projecting a pattern of a mask on a photosensitive substrate, a stage, for holding the photosensitive substrate, movable in an optical-axis direction of the projection optical system and in a direction perpendicular to the optical axis, a position detection system for outputting a detection signal corresponding to a deviation of the projection optical system in the optical-axis direction between an imaging plane of the projection optical system and the surface of the photosensitive substrate by projecting a beam of light assuming a predetermined shape on the photosensitive substrate and, at the same time, photoelectrically detecting the reflected light from the photosensitive substrate, a fiducial member provided on the stage and having a fiducial pattern assuming a predetermined shape, and a device for detecting an irradiation position of the light beam within a plane perpendicular to the optical axis of the projection optical system o

Abstract: An optical scanner with high optical scanning speed without low optical information detection accuracy and which has superior shock and vibration resistance because of its light weight has a scanner used for directing the reflected light to a light receiving element during optical scanning of an object to be read. The scanner has an optical scanning mirror and multiple light receiving mirrors placed at the sides of the scanning member. Each of the mirrors are mounted on a base, through supporting columns and beams so that they can be displaced in two-dimensional directions. Also, electrodes are provided opposite each of the mirrors on the base.

Abstract: A curvature or bending and displacement sensor is composed of a fiber optic or light wave guide, for attachment to a member or members being curved or displaced. Light is injected at one end and detected at the other end. Curvature of the fiber results in light loss through an emission surface or surfaces, sometimes in conjunction with a superimposed curvature in a plane other than that of the curvature to be measured, this loss being detected. The loss of light detection is used to produce indication of curvature or displacement. The light emission surfaces extend in various forms, such as a surface strip or band. Particularly, in an example, the emission surfaces extend in a substantially peripheral direction, or in a substantially curved axial direction when in a curved portion of a curved guide. The placement, shape and configuration of the emission surfaces allows adjustment of the linear range of measurement, the overall throughput of light, and the length over which curvature is measured.

Abstract: In a range finder, a capacitor for light emission is charged by turning off first and second switching elements and turning on third and fourth switching elements before light is emitted from a light emitting diode. A sum of a charging voltage of the capacitor for light emission and the voltage of a direct current power source is applied to the light emitting diode by turning on the first and second switching elements and turning off the third and fourth switching elements when light is emitted from the light emitting diode. At this time, an operation of the second switching element is controlled with a constant electric current by a constant current control circuit constructed by a transistor, a resistor for current limitation, a diode, etc. so that an electric current flowing through the light emitting diode is constant and a light emitting amount of the light emitting diode becomes constant.

Abstract: A portable, hand held light source unit is employed to check operation of fire detectors, such as hydrogen fire detectors. The unit emits radiation in a narrow band of wavelengths which are generated by the type of fire to be tested, but not by other light sources such as the sun or incandescent lamps. The unit can test fire detectors at different distances, and of different sensitivities. The intensity of the radiation emitted by the unit is adjustable for this purpose by means of a rotatable disk having a plurality of different sized apertures for selective placement between the light source and an output lens. The disk can also be rotated to a calibration position which causes a microprocessor circuit in the unit to initiate a calibration procedure. During this procedure, the lamp intensity is measured by a photodetector contained within the unit, and the microprocessor adjusts the lamp current to insure that its intensity remains within a preset range of values.