Abstract: A free space laser communication system operates at two power levels. The system includes a microprocessor to control the laser output beam to a safety level when the input beam indicates that the output beam is not being received at the remotely positioned terminal. If the output beam is not being received by the remotely positioned terminal, a blockage or misalignment of the beam is indicated. During normal operation when a blockage or misalignment of the beam is not detected, the output beam may be operated at a level higher than a safety limit to thereby provide enhanced communication performance.

Abstract: A color scanner has a plurality of rows of photosensors. Spacers are formed between and around the rows, and a transparent cover sheet is sealed to the device, to form separate channels. An opening is provided in each otherwise sealed channel. The channels are filled with different colored media by evacuating the channels and letting the vacuum draw in different colored media such as liquids or gels.

Abstract: A variably pressurizable support system for supporting and orienting a radiation detector, and a method for orienting a radiation detector on a moving radiation source are disclosed. The support system comprises at least one pressurizable support membrane, at least one pressurizing means able to variably pressurize the support membrane, and a control apparatus for determining the desired orientation of the radiation detector and varying the pressure in the support membrane. The method of orienting the radiation detector on the radiation source comprises the steps of determining an actual orientation of the radiation detector, and a desired orientation of the detector, and operating the support system so as to minimize the difference between the desired and actual orientation. A statically pressurized, inflatable support system for supporting the radiation detector in a fixed relation to ground is disclosed.

Abstract: An output circuit is disclosed in which the signals to instruct the output devices to conduct or to non-conduct are coupled to the devices through optical signals. The effects of undesired parasitic signals which distort the desired signal are compensated for by capacitors in the circuit. The speed of operation for the circuit is substantially higher than can be achieved using phototransistor detection methods.

Abstract: Using ion implant isolation, applicant has demonstrated a substantially planar quantum well photodetector free of exposed mesa side walls and having performance characteristics comparable with conventional mesa QWIPs. The planar photodetector presents a topography well suited for integration with other electronic components and the planar structure can be scaled to diameters much smaller than are typically useful in the conventional bonded devices.

Abstract: Optically powered sensing apparatus which has a photodiode for converting optical power to electrical energy and a switching voltage converter for optimizing power transfer from the photo diode. A controller intermittently provides a synchronizing pulse train and a synchronizing receiver detects periods when optical power drops to zero. A transducer with driving and readout electronics provides electrical parameter signals which are digitized and synchronously transmitted to the controller during the periods of no optical power from the controller. Voltage regulation, impedance matching, and temperature compensation of the photodiode optimize power transfer.

Abstract: In an embodiment for obtaining accurate noise figure measurements for any degree of saturation of an optical amplifier, a polarizer is located at the output of the optical amplifier. The amplified spontaneous noise (ASE) produced by an optical amplifier is not polarized, whereas the amplified signal has a well defined state of polarization which is preferably linear. If the amplified signal is not linearly polarized, it can be rendered linearly polarized in one direction by means of a polarization controller located downstream of the polarizer. By setting the polarizer to have its state of polarization orthogonal to that of the linearly polarized amplified signal, the spectral density of the ASE from the polarizer can be measured without associated distortion due to the signal. By sequentially adjusting the polarization controller to minimize and then maximize the signal which it passes, sequential measurements of the ASE spectral density and gain of the optical amplifier can be obtained.

Abstract: An optical angular position sensing system determines the angular position of a primary, beam-directing mirror by sensing the position of a beam from a secondary light source reflected from a secondary mirror on the back surface of the primary mirror. The position sensing system includes a photodetector that produces two output currents, the difference of which represents both the position of the reflected secondary beam and the intensity of the light source. A second servo-loop dynamically normalizes the output of the sensor by controlling the intensity of the light source to stabilize the total output of the sensor. The light source is oriented relative to the secondary mirror such that the mirror reflects a long dimension of a cross-section of the beam in a direction which is perpendicular to the direction of beam movement.

Abstract: A solid-state relay with delayed turn-on time without substantially increasing the time to bring the relay to full conduction after the delay. A current limiter disposed in series with photodiode array limits current therefrom to delay turn-on until the gate voltage of the output transistors is approximately the threshold voltage thereof. Once the threshold voltage is reached, the current limiter is bypassed so that the photodiode array provides full current to quickly turn-on the output transistors.

Abstract: Apparatus and a method for digitizing an image having a high dynamic range is disclosed. The apparatus includes a solid-state image sensor having at least two linear charge-coupled device arrays thereon. Means is provided to pass the image across the image sensor to be sensed by all of the arrays in a single pass. A light source is provided to direct light from the image onto the arrays. The arrays are provided with means to adjust the arrays so that at least one array is sensitive to low optical densities and at least one array is sensitive to high optical densities. The output signals from the arrays are feed to analog-to-digital converters to convert the signals therefrom to digital form. The digital signals are fed to a computer which combines the signals into a single signal corresponding to the image.

Abstract: A photodetection system and related circuitry designed to sense the intrusion of an opaque object in a light plane. Upon sensing the intrusion, the system quickly initiates a machine-stopping sequence prior to the opaque object coming into contact with the machine while that machine is operating. The system comprises a SYSTEM microcontroller and a WATCHDOG microcontroller, both of which operate an output control device of the light curtain switch of the invention, wherein the output control device comprises a plurality of electromechanical relays. Both microcontrollers also perform system hardware and software integrity checks. Furthermore, the WATCHDOG microcontroller evaluates the performance of the SYSTEM microcontroller by transmitting a false intrusion signal to a photosource, determining whether the false signal has been detected, and then verifying that the SYSTEM microcontroller has initiated the machine-stopping sequence.

Abstract: A device for optically detecting a chemical change of fluid comprises a prism placed in fluid to be tested and a layer of color indication material formed on a surface of the prism to thereby detect a chemical change of fluid by means of a transmitted light and a reflected light in the prism.

Abstract: The improved power supply of the present invention adjusts the voltages applied to an image tube to provide automatic brightness control and automatically compensate for temperature changes. A first oscillator, transformer and multiplier supply DC high voltage to a microchannel plate (MCP) electron multiplier of an image tube. The oscillator is controlled via control circuitry to modify the voltage applied to the MCP to automatically compensate for temperature changes associated with an image tube and to provide an automatic brightness control mode of operation. A second oscillator, transformer and individual multipliers are used to supply appropriate DC voltages to the cathode and screen of an image tube; these voltages are also automatically adjusted for temperature changes associated with the image tube. The screen current is detected and is used by additional control circuitry as feedback for the first oscillator to provide the automatic brightness control mode of operation.

Abstract: The disclosed apparatus comprises a charged particle beam system and method including a particle beam generator for forming a beam of electrons, ions or other charged particles and for directing the beam along a predetermined axis to a focal point. Object support means support an object on the particle beam axis with the focal point on a surface of the object. There is provided an optical beam system forming part of an autofocusing system for maintaining the relative positions of the beam generating means and the object support means along the particle beam axis. The optical beam system comprises means for developing an optical beam, and means for directing the optical beam transversely to the particle beam axis and at an acute angle to the object surface. Means are provided for forming an optical beam first focus on a surface of the object.

Abstract: In a push-to-release latch connected to a door/lid revolving about an axis of rotation of a cabinet between open, closed and unlatched, and closed and latched positions wherein the closed and unlatched and closed and latched positions are rotationally displaced from one another, apparatus for determining the status of the latch without sensing the latch. A reflector is carried by the door/lid or the cabinet and a non-contacting optical sensor carried by the other for directing a beam of light from an emitter, for receiving the beam of light as reflected by the reflector, and for outputting an electrical signal at an output thereof as a function of reflected light. The reflector and the non-contacting optical sensor are positioned such that the beam of light strikes the reflector to be reflected thereby when the door/lid is in a closed and latched position and the beam of light does not strike the reflector to be reflected thereby when the door/lid is in a closed and unlatched position.

Abstract: The present invention relates to a cell or holder or reflector for NIRS samples, such as capsules, tablets, or liquids. The cell comprises a main body with a top surface defining a recess. The recess is generally axially symmetrical and diverges generally upwardly from the bottom to the top of the recess. A central 90.degree. conical projection is located at the bottom of the recess and forms an annular groove with the sidewall of the recess. The sidewall of the recess has an annular notch for receiving and supporting a support window. This sidewall of the recess is parabolically shaped from the bottom to the top of the recess. The support window has intersecting grooves in its top surface over which the sample rests, or in which the sample is supported.

Abstract: An atomic force microscope is described having a scan correction arrangement. Sensors detect the actual position of tubular scanners for a sample in an xy plane. This position information is then used for post-imaging correction or as a feedback signal. Detection and use of the actual position assures that errors caused by hysteresis, etc., are obviated. Various embodiments of an appropriate sensor are described.

Abstract: In an optical output device wherein a beam of light is generated and focused to a spot upon an image plane, such as a photoreceptor in a xerographic printing apparatus, an apparatus for controlling the position of the spot in the slow scan direction of the image plane including a light source capable of emitting the beam of light at a selected one of at least two selectable wavelengths and beam deflecting means for deflecting the beam of light an amount which depends on the wavelength of the beam of light, the amount of deflection determining the position of the spot in the slow scan direction on the image plane. The light source may be of the solid state laser type, and may emit a plurality of beams of light the spots from which may be individually or together selectively positioned in the slow scan direction on the image plane. The beam deflecting element may be a semiconductor prism, for example of AlGaAs, and have a controllable bias applied thereto to allow further control of spot positioning.

Abstract: An imaging device of the present invention, utilized for game cards or the like, comprises an optical validation sensor configured to prevent fraudulent play by a retailer or the like to pick out winning game cards. The optical validation sensor activates the imaging device only upon sensing a predetermined amount or density of light passing through the game card. The imaging device also comprises a debris slot to prevent debris or the like from collecting therein when accompanied with a card being inserted and improved configurations of the game card.

Abstract: An optical switching apparatus wherein one or more information-bearing collimated laser beams are each launched into free-space and directed onto a selected photo-receptor to effect an optical cross-connection. Each launched beam is split into two separate components: a payload component, and a monitor component. The payload component of the beam is directed toward a photo-receptor, and the monitor component is directed toward a photo-sensor. The direction in which a particular information-bearing beam is launched is controlled in response to feedback received from the photo-sensor as a function of the position the monitor component associated with that information-bearing beam.