Bridge And Push-pull Circuits Patents (Class 250/210)
  • Patent number: 11370216
    Abstract: An apparatus and method for measuring the thickness of fountain solution (FS) in a Digital Architecture for Lithographic Ink (DALI) printing system by transferring the FS to an optical roller with the properties of a lens and measuring the resulting effect on the refraction of an image captured through the lens. The optical roller may comprise a clear or glass cylinder forming a Fresnel lens cylinder having an engineered surface of known surface roughness and wherein the roller is placed adjacent the image member blanket. A heat source is used to evaporate the FS from the blanket for transfer to the optical roller where the FS wets the roller surface to different degrees based on the FS thickness relative to Fresnel ridge depth. Changes to the optical refraction through the lens varies with the FS thickness. An image sensor (e.g., a CCD camera or image analysis system) evaluates the image through the optical roller for FS thickness determination.
    Type: Grant
    Filed: January 29, 2021
    Date of Patent: June 28, 2022
    Assignee: Xerox Corporation
    Inventors: Douglas K. Herrmann, Chu-Heng Liu, Seemit Praharaj, Jason M. Lefevre, Paul J. McConville
  • Patent number: 11170969
    Abstract: Provided is an electron beam observation device that includes: an electron source; an objective lens concentrating an electron beam emitted from the electron source; and a control unit configured to perform control such that a plurality of images is generated by capturing images of a reference sample having a specific pattern, and a frequency characteristic is calculated for each of the plurality of images, in which an image is generated based on a secondary signal generated from a sample due to irradiation of the sample with the electron beam, and the control unit holds the plurality of frequency characteristics.
    Type: Grant
    Filed: March 30, 2018
    Date of Patent: November 9, 2021
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Koichi Hamada, Megumi Kimura, Momoyo Enyama, Ryou Yumiba, Makoto Sakakibara, Kei Sakai, Satoru Yamaguchi, Katsumi Setoguchi
  • Patent number: 10788729
    Abstract: A laser beam phase-modulation device, a laser beam steering device, and a laser beam steering system including the same are provided. The laser beam phase-modulation device includes a refractive index conversion layer having a refractive index that is changed according to an electrical signal applied thereto, the refractive index conversion layer including an upper surface on which the laser beam is incident and a lower surface opposite the upper surface, at least one antenna pattern embedded in the upper surface of the refractive index conversion layer, and a metal mirror layer provided under the lower surface of the refractive index conversion layer and configured to reflect the laser beam.
    Type: Grant
    Filed: August 7, 2017
    Date of Patent: September 29, 2020
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Sunil Kim, Changgyun Shin, Byounglyong Choi
  • Patent number: 9909926
    Abstract: We disclose a chemical sensing device for detecting a fluid. The sensing device comprises: at least one substrate region comprising at least one etched portion; a dielectric region formed on the at least one substrate region, the dielectric region comprising at least one dielectric membrane region adjacent to the at least one etched portion; an optical source for emitting an infra-red (IR) signal; an optical detector for detecting the IR signal emitted from the optical source; one or more further substrates formed on or under the dielectric region, said one or more further substrates defining an optical path for the IR signal to propagate from the optical source to the optical detector. At least one of the optical source and optical detector is formed in or on the dielectric membrane region.
    Type: Grant
    Filed: May 31, 2016
    Date of Patent: March 6, 2018
    Assignee: AMS SENSORS UK LIMITED
    Inventors: Richard Henry Hopper, Andrea De Luca, Kaspars Ledins, Syed Zeeshan Ali, Mohamed Foysol Chowdhury
  • Patent number: 9419024
    Abstract: An electro-optic display comprises a substrate (100), non-linear devices (102) disposed substantially in one plane on the substrate (100), pixel electrodes (106) connected to the non-linear devices (102), an electro-optic medium (110) and a common electrode (112) on the opposed side of the electro-optic medium (110) from the pixel electrodes (106). The moduli of the various parts of the display are arranged so that, when the display is curved, the neutral axis or neutral plane lies substantially in the plane of the non-linear devices (102).
    Type: Grant
    Filed: February 27, 2015
    Date of Patent: August 16, 2016
    Assignee: E INK CORPORATION
    Inventors: Andrew P. Ritenour, Gregg M. Duthaler
  • Patent number: 8198576
    Abstract: A 3-D LADAR imaging system incorporating stacked microelectronic layers is provided. A reference insert circuit inserts data into the FIFO registers at a preselected location to provide a reference point at which all FIFO shift register data may be aligned to accommodate for timing differences between layers and channels. The bin data representing the photon reflections from the various target surfaces are read out of the FIFO and processed using appropriate circuitry such as a field programmable gate array to create a synchronized 3-D point cloud for creating a 3-D target image.
    Type: Grant
    Filed: October 10, 2008
    Date of Patent: June 12, 2012
    Assignee: Aprolase Development Co., LLC
    Inventors: John Kennedy, David Ludwig, Christian Krutzik
  • Publication number: 20110100798
    Abstract: The present invention provides a method for extracting a charged particle beam from a charged particle source. A set of electrodes is provided at the output of the source. The potentials applied to the electrodes produce a low-emittance growth beam with substantially zero electric field at the output of the electrodes.
    Type: Application
    Filed: January 10, 2011
    Publication date: May 5, 2011
    Applicant: FEI Company
    Inventors: Roderick Boswell, Orson Sutherland
  • Patent number: 7800075
    Abstract: A multifunction module for an electron beam column comprises upper and lower electrodes, and a central ring electrode. The upper and lower electrodes have multipoles and are capable of deflecting, or correcting an aberration of, an electron beam passing through the electrodes. A voltage can be applied to the central ring electrode independently of the voltages applied to the upper and lower electrodes to focus the electron beam on a substrate.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: September 21, 2010
    Inventors: Benyamin Buller, William J. DeVore, Juergen Frosien, Xinrong Jiang, Richard L. Lozes, Henry Thomas Pearce-Percy, Dieter Winkler, Steven T. Coyle, Helmut Banzhof
  • Patent number: 7399964
    Abstract: The present invention relates to an electron microscope which reduces a difference in measured values that occur due to a difference in resolution that cannot be fully adjusted which exists among electron microscopes, or occurs as time elapses, and a method for measuring dimensions. An operator adapted to compensate for changes of an electron image to be generated due to a difference in probe diameter is obtained in advance from electron images of one reference sample created by electron microscopes having different resolution (probe diameter). Then a compensation-measurement electron image which is equivalent to an electron image created under the same probe diameter by applying the operator for compensation, and the compensation-measurement electron image is used for measuring the dimensions.
    Type: Grant
    Filed: May 3, 2005
    Date of Patent: July 15, 2008
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Chie Shishido, Ryo Nakagaki, Mayuka Oosaki, Hiroki Kawada
  • Patent number: 7193200
    Abstract: The invention relates to a receiver arrangement for a push-pull transmission method. First and second signal detectors, to which a first input signal is fed provide first and second detector signals depending on a comparison of the first input signal with a detector threshold. Third and fourth signal detectors, to which a second input signal is fed provide third and fourth detector signals depending on a comparison of the second input signal with a detector threshold. The first and third detector signals are respectively fed to a data input of a first and second buffer store. The second and fourth detector signals are respectively fed to a reset input of the first and second buffer store. The first and second buffer store are designed for buffer-storing signal pulses contained in the first and second detector signals and forwarding them to a respective output for subsequent further processing in time-delayed fashion after a first delay duration.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: March 20, 2007
    Assignee: Infineon Techologies AG
    Inventors: Karim-Thomas Taghizadeh-Kaschani, Jose Maria Martinez
  • Patent number: 7005638
    Abstract: In a device for examining a specimen with an electron beam, in particular an SEM, TEM, or CSEM, contamination products are often result from the irradiation. To reduce these contamination products, the surface of the object irradiated with the electron beam is simultaneously illuminated with light, in particular with UV light.
    Type: Grant
    Filed: March 8, 2004
    Date of Patent: February 28, 2006
    Assignee: Leica Microsystems Semiconductor GmbH
    Inventor: Burkhard Spill
  • Patent number: 6965103
    Abstract: This disclosure is generally concerned with devices for determining photocurrent levels. One example of such a device is an optoelectronic device that includes a photodetector. The photodetector is configured to receive an optical signal and generate a corresponding electrical signal. The electrical signal is received by a pre-amplifier circuit which then converts the received electrical signal to a differential output. Finally, a post-amplifier circuit in communication with the first stage circuit is configured to derive an optical signal strength of the optical signal based upon the differential output received from the pre-amplifier circuit.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: November 15, 2005
    Assignee: Finisar Corporation
    Inventor: Phil Shapiro
  • Publication number: 20040046101
    Abstract: The present invention provides a pixel which utilizes a charge multiplying photoconversion element. An output control circuit contains an operational amplifier that serves to fix the voltage level at the storage node to thereby maintain a constant effective operating potential across the charge multiplying photoconversion layer. The detected light signal may be converted to provide linear, logarithmic, and linear-logarithmic output signals.
    Type: Application
    Filed: August 23, 2002
    Publication date: March 11, 2004
    Inventors: Junichi Nakamura, Isao Takayanagi
  • Publication number: 20030213893
    Abstract: A defect inspecting apparatus is provided for generating a less distorted test image to reliably observe a surface of a sample for detecting defects thereon. The defect detecting apparatus comprises a primary electron beam source for irradiating a sample, electrostatic lenses for focusing secondary electrons emitted from the surface of the sample irradiated with the primary electron beam, a detector for detecting the secondary electrons, and an image processing unit for processing a signal from the detector. Further, a second electron source may be provided for emitting an electron beam irradiated to the sample, wherein the sample may be irradiated with the electron beam from the second electron source before it is irradiated with the primary electron beam from the first electron source for observing the sample. A device manufacturing method is also provided for inspecting devices under processing with high throughput using the defect detecting apparatus.
    Type: Application
    Filed: May 15, 2003
    Publication date: November 20, 2003
    Applicants: EBARA CORPORATION, KABUSHIKI KAISHA TOSHIBA
    Inventors: Ichirota Nagahama, Yuichiro Yamazaki, Kenji Watanabe, Masahiro Hatakeyama, Tohru Satake, Nobuharu Noji
  • Patent number: 6359324
    Abstract: A semiconductor device that has a p-n junction with a photosensitive region partially having a diffusion region and a non-diffused region when the p-n junction is subjected to a reverse bias voltage. When an incident light (e.g. a laser) is directed at the surface of the photosensitive region, hole-electron pairs are generated in the partial diffusion region within the photosensitive region. As a result, the current through the photosensitive region changes in a substantially linear fashion with the intensity of the incident light. The semiconductor device can be configured in a circuit to provide substantially linear power amplification. The semiconductor device can be configured by itself or with a complimentary device to form push-pull operations.
    Type: Grant
    Filed: May 22, 2000
    Date of Patent: March 19, 2002
    Assignee: Ophir RF, Inc.
    Inventor: Larry M. Tichauer
  • Patent number: 5973313
    Abstract: A ratiometric sensor is formed of a first photodiode connected in series with an electronic component, such as a second photodiode or a resistor, between a source of first voltage and a source of second voltage. The ratiometric sensor supplies a "ratiometric voltage" on a ratiometric sensor output line that is connected to a junction between the first photodiode and the electronic component. The ratiometric voltage is proportional to the ratio of the equivalent resistance of the first photodiode to the sum of the equivalent resistances of the first photodiode and the electronic component. A ratiometric sensor that uses a photodiode and a resistance has a large dynamic range because the ratiometric voltage can vary between the first voltage and the second voltage. A ratiometric sensor that uses two photodiodes is less sensitive to noise than a conventional circuit that uses a single photodiode, because noise can get canceled from the numerator and denominator of the ratio.
    Type: Grant
    Filed: November 19, 1996
    Date of Patent: October 26, 1999
    Assignee: TV Interactive Data Corporation
    Inventors: Peter M. Redford, Donald S. Stern
  • Patent number: 5650608
    Abstract: A ratiometric sensor is formed of a first photodiode connected in series with an electronic component, such as a second photodiode or a resistor, between a source of first voltage and a source of second voltage. The ratiometric sensor supplies a "ratiometric voltage" on a ratiometric sensor output line that is connected to a junction between the first photodiode and the electronic component. The ratiometric voltage is proportional to the ratio of the equivalent resistance of the first photodiode to the sum of the equivalent resistances of the first photodiode and the electronic component. A ratiometric sensor that uses a photodiode and a resistance has a large dynamic range because the ratiometric voltage can vary between the first voltage and the second voltage. A ratiometric sensor that uses two photodiodes is less sensitive to noise than a conventional circuit that uses a single photodiode, because noise can get canceled from the numerator and denominator of the ratio.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: July 22, 1997
    Assignee: TV Interactive Data Corporation
    Inventors: Peter M. Redford, Donald S. Stern
  • Patent number: 5064274
    Abstract: A variable reflectivity automobile mirror assembly is operable by automatic electrical circuitry responsive to variations of incident light upon the mirror and ambient light level about the automobile to provide positions of high and low reflectivity. The assembly also includes a support member or housing, a reflective mirror panel, motor means, actuation means secured to the housing and driven by the drive element of the motor, and a timed-drive circuit for directing the current through the motor in opposite directions to move the mirror between the two positions. the automatic circuitry can include photosensing means and means to combine the output of the photosensing means and to compare it to an independent source. The circuit can position the mirror in response to the output of the comparing means.
    Type: Grant
    Filed: March 30, 1989
    Date of Patent: November 12, 1991
    Assignee: Siegel-Robert, Inc.
    Inventor: Ralph W. Alten
  • Patent number: 4950076
    Abstract: A system for improving the dynamic range of guidance systems for missiles d bombs by replacing pseudo-logarithmic amplifiers in the processing circuits with transimpedance amplifiers having feed back impedance operating in conjunction with lower bandwidth type logarithmic amplifiers in the log of the ratio circuits.
    Type: Grant
    Filed: September 14, 1976
    Date of Patent: August 21, 1990
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Bobby R. Jarrett
  • Patent number: 4940967
    Abstract: A digital control circuit uses a single infrared detector to control the clock pulse on a digital counter so that the sensitivity control is based on the length of time a change in infrared radiation persists. A pyroelective detector is located in a voltage divider and the intermediate voltage of the divider is digitally compared to the intermediate voltage in a fixed divider as a digitaly controlled pulse is applied to both dividers. Either an increase or a decrease of infrared radiation causes the digital circuit to permit the counter to be activated.
    Type: Grant
    Filed: August 31, 1989
    Date of Patent: July 10, 1990
    Assignee: Burle Technologies, Inc.
    Inventor: Edgar M. Smith
  • Patent number: 4902884
    Abstract: In a circuit arrangement for carrying out light intensity measurements, comprising an input terminal (5), an output terminal (6), a first and a second photodiodes (D.sub.1, D.sub.2) for receiving light emitted by an optical light source (S) and a first and a second operational amplifiers (1, 2) for receiving output current signals of the first and second photodiodes (D.sub.1, D.sub.2) generated under influence of the emitted light, the novelty lies in further comprising a four branch bridge circuit including in two adjacent branches the first and second photodiodes (D.sub.1, D.sub.2) coupled to a common point by their respective poles of the same sign and oppositely to them in the further two adjacent branches two bridge resistors (R.sub.1, R.sub.
    Type: Grant
    Filed: April 5, 1988
    Date of Patent: February 20, 1990
    Assignee: Dunacoop Kereskedelmi es Idegenforgalmi Vallalkozasokat Szervezo Szolgaltato Lebonyolitacu/o/ GT
    Inventors: Gabor Szabo, Marta S. Burgert
  • Patent number: 4769533
    Abstract: The invention relates to a circuit arrangement for a position sensitive radiation detector which produces a current or voltage signal (U.sub.Y) that depends exclusively on the coordinates x and y of the point of incidence of electromagnetic radiation on the EMR sensitive surface of a lateral diode (1). For this purpose, the circuit arrangement has integrators (4, 5), in which the voltages (U.sub.1, U.sub.2) are formed, which are proportional to the integral over time of the output currents (I.sub.1, I.sub.2) of the lateral diode (1). The difference between the voltages (U.sub.1, U.sub.2) is used as a signal, which depends exclusively on the coordinates at that particular time, at which the arithmetic mean of these voltages (U.sub.1, U.sub.2) has reached a preselected, constant value.
    Type: Grant
    Filed: August 17, 1987
    Date of Patent: September 6, 1988
    Assignee: Leybold-Heraeus GmbH
    Inventors: Martin Groschl, Gerd Pfersmann
  • Patent number: 4717820
    Abstract: A device for detecting movable objects within a limited detection area comprises a number of juxtaposed photosemiconductors (A, B) on which an image of the detection area is adapted to impinge and which are uniformly distributed on branches (10, 11) of an electric bridge circuit, such that two juxtaposed photoresistors (A and B, respectively) are included in separate bridge branches (10 and 11, respectively). The bridge branches (10, 11) are connected to a rectifier (13) for generating an output signal.
    Type: Grant
    Filed: January 9, 1986
    Date of Patent: January 5, 1988
    Inventor: Bert O. Jonsson
  • Patent number: 4651023
    Abstract: An electronic switch has a pair of light dependent resistors forming part of a potential divider with the hysteresis of the circuit being high enough to prevent equally applied changes in light level from effecting the switch action. The divider controls the voltage to an operational amplifier which is switched off by covering the other resistor. The switch may be combined with an opto-isolator or a relay to control power circuits.
    Type: Grant
    Filed: May 29, 1985
    Date of Patent: March 17, 1987
    Assignee: Development Finance Corporation
    Inventor: Peter C. J. Parsonage
  • Patent number: 4624572
    Abstract: Spectrophotometric apparatus is incorporated in a portable housing with a light source for emitting a wide band of radiation from which monochromatic light is produced and projected onto a specimen outside the housing. A hood is mounted to the housing and includes an aperture through which light is emitted from the light source and reflected from either a specimen or a calibrating material positioned in front of the aperture such that light is reflected from either the specimen or the calibrating material onto a photosensitive detector within the housing. The photosensitive detector is responsive to the monochromatic light reflected from the specimen or the calibrating material to provide output signals representative of the spectrophotometric characteristics thereof. The output of the photosensitive detector is connected to an indicating meter.
    Type: Grant
    Filed: March 21, 1984
    Date of Patent: November 25, 1986
    Inventor: Francois J. G. van den Bosch
  • Patent number: 4302668
    Abstract: A photoelectric circuit is provided with a differential amplifier having two inputs. First and second photosensitive elements and resistors are connected in parallel to each of the two inputs of the differential amplifier, respectively. A second amplifier is provided with its input coupled in parallel to a third resistor and a third photosensitive element. The output of the second amplifier is applied as a bias voltage to each of the three photosensitive elements in parallel.
    Type: Grant
    Filed: November 23, 1979
    Date of Patent: November 24, 1981
    Assignee: Dr. Johannes Heidenhain GmbH
    Inventor: Walter Schmitt
  • Patent number: 4143264
    Abstract: A highway line detection system for an automobile which provides an output signal when a traffic line on a pavement under an automobile is about to be crossed. It includes a photoelectric sensor connected to an electrical bridge circuit, and the bridge circuit includes an impedance element which is varied in impedance responsive to the integrated output of the bridge circuit, and thereby the bridge circuit is maintained in balance for ambient light conditions. Further, the threshold of detection of the system, at which point an alarm is sounded, is varied as a function of the ambient light state, whereby the sensitivity of the system is increased for low light conditions and decreased for high light conditions to compensate for an opposite characteristic of the photosensor.
    Type: Grant
    Filed: October 20, 1977
    Date of Patent: March 6, 1979
    Inventors: William J. Gilbert, Ronald W. Klassen
  • Patent number: 4078151
    Abstract: A graphics panel is disclosed which translates any random trace of a point light source across the panel into voltage indicative of orthogonal components of the displacement of the light source. By means of such electrical signals a replica of the trace of the light source may be generated by a cathode ray tube, X-Y Plotter, or similar analog devices. The display panel is a flat planar structure composed of transparent plastic material having one side rendered opaque. A plurality of photoconductors are arrayed along the peripheral side of the panel and appropriate electrical circuits incorporating the photoconductors convert the current generated thereby into the voltages proportional to the displacement of the light source along orthogonal axes in the plane of the panel.
    Type: Grant
    Filed: October 18, 1976
    Date of Patent: March 7, 1978
    Assignee: Wisconsin Alumni Research Foundation
    Inventor: James J. McNeary
  • Patent number: 4048596
    Abstract: A remote control unit for an electrical appliance includes a pair of photocells and one or more threshold devices connected to sense differential illumination of the photocells. The threshold devices, in turn, emit signals that initiate operation of a control device connected to the appliance. The threshold devices are preferably gaseous discharge lamps whose light outputs are sensed by radiation-response switching circuitry.
    Type: Grant
    Filed: April 17, 1975
    Date of Patent: September 13, 1977
    Assignee: Signal Science Systems, Inc.
    Inventors: Eric A. Kolm, Robert R. Trottier
  • Patent number: 4030840
    Abstract: A waveform sampler, for cooperation with a conventional sampling oscilloscope, has, as part of a bridge circuit, two Gallium Arsenide photoconductors mounted on a 50 ohm stripline. One GaAs photoconductor, the sampling photoconductor, is illuminated. The other GaAs photoconductor remains dark and functions as a common mode compensating photoconductor. To sample an unknown electrical waveform traversing the stripline the electrical wave is optically strobed by illuminating the sampling GaAs photoconductor with pulses of light from a laser. To sample an unknown optical waveform the optical wave is focused on the sampling GaAs photoconductor and an electrical strobe signal is sent through the stripline. Outputs from each of the photoconductors are amplified in high input impedance FET amplifiers and after electrical compensation they are passed to a conventional difference amplifier. The difference output is further amplified and fed to a conventional sampling oscilloscope.
    Type: Grant
    Filed: March 25, 1976
    Date of Patent: June 21, 1977
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Robert A. Lawton, James R. Andrews
  • Patent number: 4016423
    Abstract: This invention relates to an improved infrared analyzer, wherein the total radiant energy reaching the detector is maintained at a constant value independently from the aging of the source of radiant energy or the soiling of the sample cell. According to the invention, the improved infrared analyzer comprises a comparator, whose outlet feeds the radiant energy source and whose inlets receive a reference signal of constant value and, respectively, a signal which varies as a function of the total radiant energy received and measured by the detector.
    Type: Grant
    Filed: January 20, 1976
    Date of Patent: April 5, 1977
    Assignee: Leeds & Northrup Italiana S.p.A.
    Inventor: Emilio G. Meyer
  • Patent number: 4012663
    Abstract: Spectral output of lamp is controlled by a combination of color filters and dual photocell which monitors the spectral composition of the radiant energy from the lamp and compensates for change therein by automatically varying the power applied to the lamp to provide constant spectral output.
    Type: Grant
    Filed: November 25, 1974
    Date of Patent: March 15, 1977
    Assignee: General Electric Company
    Inventor: Trasimond A. Soileau
  • Patent number: 3984676
    Abstract: This invention relates to a light-measuring apparatus wherein a photoelectric element is arranged in a leg of a measuring bridge, the output voltage of said element controlling the brightness of two signal lamps.
    Type: Grant
    Filed: October 18, 1974
    Date of Patent: October 5, 1976
    Assignee: Durst AG. Fabrik Fototechnischer Apparate Bozen
    Inventor: Siegfried Barbieri
  • Patent number: 3955081
    Abstract: An exposure control circuit connected with an electrically operated exposure control element such as an electric shutter or an electrically controlled diaphragm includes a bridge circuit. The bridge circuit has four arms and is provided in one arm thereof with a photodetector to receive light from the object to be photographed. A resistor is connected in series with the photodetector to convert the current flowing through the photodetector into a voltage. A transistor is connected with the photodetector to amplify the photocurrent thereof. Another resistor is connected with the transistor to convert the current obtained by amplification of the photocurrent of the photodetector by use of the transistor to a voltage. These two resistors are provided in one arm of the bridge circuit so as to be independently varied of their resistance.
    Type: Grant
    Filed: April 2, 1974
    Date of Patent: May 4, 1976
    Assignee: Fuji Photo Optical Co., Ltd.
    Inventors: Takayoshi Sato, Kunio Ando
  • Patent number: 3943360
    Abstract: Pulse detection apparatus for optical signal pulses including ultra-violet and infra-red frequencies. A photoconductive detector cell has four ohmic output electrode terminals disposed in a rhombic pattern and a centrally disposed input electrode terminal coupled to a source of direct current bias signal. Each pair of oppositely disposed output terminals defines an axis orthogonal to that defined by the other pair. Each pair of output terminals is coupled to a signal translation device such as a transformer with a center tapped primary or a differential amplifier. A pair of output signals are produced indicative of the degree of unbalance of the cell due to an optical signal impinged thereon.
    Type: Grant
    Filed: August 12, 1968
    Date of Patent: March 9, 1976
    Assignee: Sanders Associates, Inc.
    Inventor: William J. Parkin