Abstract: An active matrix circuit having a simplified circuit configuration is disclosed. The active matrix circuit includes selection lines extending along rows, signal lines extending along columns, active devices disposed at respective locations where the selection lines and the signal lines cross each other, a vertical scanning circuit for outputting selection pulses to sequentially scan the selection lines thereby selecting active devices, and a horizontal scanning circuit for outputting control pulses to open or close the respective signal lines thereby inputting or outputting a signal to selected active devices.
Abstract: A quantum well infrared photodetector focal plane array is disclosed wherein each detector structure of the array comprises two vertically stacked quantum well layers. Each of the quantum well layers are individually biased by separate bias voltages and the separate bias voltages are modulated to produce two or more measurements at different spectral bands. Each detector structure of the array can therefore perform measurements of incident infrared energy in at least four separate spectral bands. This technique of measuring incident infrared energy in four separate spectral bands can advantageously be applied to the discrimination of hot gas sources from background infrared clutter.
Abstract: A low voltage optical phase modulator includes a splitter having an input, a first output, and a second output. The input receives an optical signal and is split between the first and second outputs. A phase adjustment element is coupled to the second output and produces a predetermined optical shift in the optical signal to produce a phase-shifted optical signal. A first electroabsorptive element is coupled to the first output and blocks transmission of the optical signal when the first electroabsorptive element is activated with a low voltage. A second electroabsorptive element is coupled to the phase adjustment element and blocks transmission of the phase-shifted optical signal when the second electroabsorptive element is activated using the low voltage. An optical combiner having a first combiner input, a second combiner input, and a combiner output is coupled to the first and second electroabsorptive elements and receives the optical signal and the phase-shifted optical signal.
Type:
Grant
Filed:
August 20, 2001
Date of Patent:
December 2, 2003
Assignee:
The Boeing Company
Inventors:
Robert R. Hayes, Alan R. Kost, Daniel Yap, Thomas R. Cooper
Abstract: Laser scanning optics for scanning a laser beam issuing from a laser in the main scanning direction while repeatedly steering it in the subscanning direction is disclosed. The laser scanning optics includes focusing optics for focusing the laser beam, a first deflector for steering the laser beam in the subscanning direction, and a second deflector for steering the laser beam in the main scanning direction. The focusing optics causes the laser beam to form an elliptical beam spot, which is elongate in the main scanning direction, in a scanning plane. The first deflector is driven such that the laser beam is scanned at a higher speed in the subscanning direction than in the main scanning direction. The first deflector is so controlled, based on a value input beforehand or data measured beforehand, as to correct the distortion of linearity in the main scanning direction by subscanning.
Abstract: An x-ray imaging system according to the present invention comprising a stepped scanning-beam x-ray source and a multi-detector array. The output of the multi-detector array is input to an image reconstruction engine which combines the outputs of the multiple detectors over selected steps of the x-ray beam to generate an x-ray image of the object. A collimating element, preferably in the form of a perforated grid containing an array of apertures, interposed between the x-ray source and an object to be x-rayed. A maneuverable positioner incorporating an x-ray sensitive marker allowing the determination of the precise position coordinates of the maneuverable positioner.
Type:
Grant
Filed:
January 7, 1999
Date of Patent:
November 18, 2003
Assignee:
Cardiac Mariners, Inc.
Inventors:
Jack W. Moorman, Brian Skillicorn, Edward G. Solomon, Peter J. Fiekowsky, John W. Wilent, Abigail A. Moorhouse, Robert E. Melen
Abstract: The invention relates to apparatus and methods for suppressing high frequency resonance in an electro-optical device. The electro-optical device includes an optical waveguide formed in the upper surface of a substrate. The device further includes a plurality of electrically floating electrode segments that are positioned on the substrate to intensify an electric field in the optical waveguide. The device also includes a plurality of electrically grounded electrode segments that are positioned on the substrate for prohibiting modal conversion and propagation of high order modes in the plurality of electrically grounded electrode segments and in the plurality of electrically floating electrode segments, thereby suppressing modal coupling to the substrate. The device further includes a buffer layer formed on the upper surface of the substrate and a driving electrode formed on an upper surface of the buffer layer for receiving an RF signal that induces the electric field in the optical waveguide.
Type:
Grant
Filed:
November 23, 2002
Date of Patent:
November 11, 2003
Assignee:
JDS Uniphase Corporation
Inventors:
Steve Cheung, Karl Kissa, Gregory J. McBrien
Abstract: Techniques and systems for mitigating polarization-related signal degradation or distortions in birefringent optical links based on intra-bit polarization diversity modulation.
Type:
Grant
Filed:
March 18, 2002
Date of Patent:
November 11, 2003
Inventors:
Alan E. Willner, Zhongqi Pan, Yan Wang, Changyuan Yu, Ting Luo, Asaf B. Sahin, Qian Yu
Abstract: The present invention uses quantum interference of one and two photon absorption from a multiple color fields to optically inject ballistic spin currents in unbiased photoconductors. The spin currents can be generated with and without an accompanying electrical current and can be controlled using the relative phase of the colors. In one aspect of the there is provided a method of generating spin currents in a photoconductor material comprising producing a first coherent light beam having a first frequency &ohgr;1 and a second coherent light beam having a frequency twice the first frequency 2&ohgr;1, polarizing the first and second coherent light beams to have a preselected polarization with respect to each other, and simultaneously irradiating a selected region of the photoconductor material with the first coherent light beam and the second coherent light beam to generate a spin current in the photoconductor.
Type:
Grant
Filed:
March 22, 2002
Date of Patent:
November 4, 2003
Inventors:
Ravi D. R. Bhat, John Edward Sipe, Henry Martin Van Driel
Abstract: A method and apparatus for configuring and tuning a crystal by selectively controlling a fluid supplied to a plurality of nodes within a substrate. The apparatus comprises a substrate having at least one node that can be selectively supplied with a liquid that will change the material property of the node. The node may be a spherical cavity in a three-dimensional structure, a cylindrical aperture in two-dimensional structure, or a cavity in a one-dimensional structure. The node or nodes in the substrate are coupled to a fluid distribution assembly that selectively alters the material property of the nodes. The material property may be changed by moving the fluid or material in a fluid, using electrohydrodynamic pumping, electroosmotic pumping, electrophoresis, thermocapillarity, electrowetting or electrocapillarity. The change in the material property in at least one of the nodes changes the electromagnetic radiation filtering or switching characteristics of the crystal.
Type:
Grant
Filed:
April 3, 2002
Date of Patent:
October 28, 2003
Assignee:
Sarnoff Corporation
Inventors:
Sterling Eduard McBride, Peter J. Zanzucchi, Joseph Hy Abeles
Abstract: A method for detecting and compensating inclination of an objective lens includes the steps of: initially driving an optical disk and detecting a record signal while travelling on the track of the optical disk; checking whether a GFS signal according to the rotation of the optical disk is normally detected; checking a center error signal value outputted from the optical pick-up which reads a record data on the optical disk in case that the GFS signal is abnormally detected; and discriminating inclination of the objective lens on the basis of the checked center error signal value, thereby judging inclination of the objective lens quickly and accurately. In order to discriminate inclination of the objective lens by the optical disk driving apparatus, the GFS signal and the center error signal generated according to the rotation of the optical disk are all taken into consideration, so that the inclination of the objective lens in the optical pick-up is accurately and quickly discriminated.
Abstract: A method and system to monitor characteristics of films by sensing the spectral emissions of a plasma to which the films are exposed. As a result, the method includes sensing optical energy produced by the plasma. The optical energy has a plurality of spectral bands associated therewith, a subset of which is identified as including information corresponding to the film characteristics. The film characteristics are then measured as a function of this information. To increase the accuracy of the measurements, in one embodiment of the present invention a subgroup of the plurality of spectral bands is observed that has data associated that is substantially independent of the characteristics of interest. The characteristics are then measured as a function of both the information and the data.
Abstract: The present invention relates to a device and a procedure for the quality control of in particular finished surfaces wherein the device comprises at least one illuminating means having at least one light source, its light directed at a predetermined angle to the measurement surface. A plurality of at least three measuring means is provided, whereby each of said measuring means is directed at a different predetermined angle to the measurement surface and receives a portion of the light reflected from said measurement surface. Each measuring means comprises at least one photosensor which emits an electrical measurement signal which is characteristic of the light received by said measuring means. A control and evaluation means having at least one processor means and one memory means controls the measurement sequence, evaluates the measurement results and derives therefrom a parameter which characterizes the surface. An output means serves for the outputting of parameters or measurement results.
Abstract: A scanning apparatus is provided, which includes a medium attached to a surface of a fixed, hollow cylindrical segment, the fixed, hollow cylindrical segment having a first longitudinal axis, a rotational radial laser beam rotating around the first longitudinal axis and arranged to scan said medium, and a light sensitive detector having a light acceptance direction along a second axis coinciding with the first longitudinal axis of the cylindrical segment.
Abstract: A metrology system and method uses pulsed light to allow continuous movement of a target relative to the sensor. A metrology system and method uses dynamic adjustment of tilt in a system. A metrology system and method calibrates the system to remove inherent optical aberrations in the system. Filtering may also be used in the system to increase accuracy.
Type:
Grant
Filed:
October 18, 2000
Date of Patent:
September 23, 2003
Assignee:
WaveFront Sciences, Inc.
Inventors:
Daniel R. Neal, Daniel R. Hamrick, Thomas D. Raymond
Abstract: Mach-Zehnder modulator with index tuned multimode interference couplers comprising a substrate, an optical input waveguide on the substrate for receiving a light signal, and an input multimode interference coupler. The input multimode interference coupler splits the received light and propagates it down two separate waveguides. Also, the input multimode interference coupler contains electrodes that allow the index of refraction to be tuned. These waveguides contain phase shift regions so that the light signals can be combined at the output multimode interference coupler out of phase. This allows the modulation of the light signal. Also, the output multimode interference coupler contains electrodes that allow the index of refraction to be tuned. The modulated light signal is then outputted through an output waveguide. The tuning of the index of refraction for the input and output multimode interference couplers eliminates the sensitivity of the areas to variations in their geometry.
Type:
Grant
Filed:
August 16, 2001
Date of Patent:
September 9, 2003
Inventors:
Srinath Kalluri, Timothy A. Vang, David C. Scott
Abstract: A radiation detector employs a thermopile having a potentiometer for calibrating the thermopile output to best suit a particular output meter and sensing application. A thermocouple may be connected in series with the thermopile. The output of the thermopile is calibrated to best match a linear function which intersects the thermopile output function at a temperature in the center of a temperature range of interest. A total output signal of the detector is the sum of the thermopile signal and the thermocouple signal, and is indicative of the temperature of a target emitting radiation sensed by the thermopile. The series connection of the thermopile and the thermocouple allow the thermopile hot junction temperature to be referenced to the cold junction temperature of the thermocouple. Thus, the reference temperature may be remote from the thermopile sensor. A filtering lens may be used to prevent short wavelength radiation from reaching the thermopile sensor, improving the linearity of the thermopile response.
Abstract: An optical detection and orientation device is provided comprising housing having an excitation light source, an optical element for reflecting the excitation light to an aspherical lens and transmitting light emitted by a fluorophore excited by said excitation light, a focussing lens for focusing the emitted light onto the entry of an optical fiber, which serves as a confocal aperture, and means for accurately moving said housing over a small area in relation to a channel in a microfluidic device. The optical detection and orientation device finds use in identifying the center of the channel and detecting fluorophores in the channel during operations involving fluorescent signals.
Type:
Grant
Filed:
May 15, 2002
Date of Patent:
September 2, 2003
Assignee:
Aclara Biosciences, Inc.
Inventors:
Kevin Maher, Timothy F. Smith, Torleif Ove Bjornson
Abstract: The invention relates to a display operating either in a reflective mode or a transmissive mode and having a high brightness. The display comprises pixel elements (20) having a switchable layer (3), which is switched between a reflecting, a transmissive and an absorbing state by changing a hydrogen content of the switchable layer. Applying a DC voltage on electroconductive layers (11, 13) changes the hydrogen content. These electroconductive layers sandwich a stack of layers comprising the switchable layer (3), which stack has been deposited on a transparent substrate.
Type:
Grant
Filed:
September 27, 2001
Date of Patent:
July 22, 2003
Assignee:
Koninklijke Philips Electronics N.V.
Inventors:
Mark Thomas Johnson, Hugo Johan Cornelissen
Abstract: System for sensing perturbations in a distributed manner using an array of multimode fibers for localization (zone identification) of the perturbation, particularly, the present invention relates to a two dimensional array based speckle pattern sensing system having 4×3 (12) multimode fibers for sensing perturbation in multiple zones, said multimode fibers are imaged in parallel by a charge coupled device (CCD) camera and their speckle pattern analyzed by a conventional image processing hardware to determine the perturbations.
Type:
Grant
Filed:
March 27, 2001
Date of Patent:
July 8, 2003
Assignee:
Council of Scientific & Industrial Research
Abstract: An image display medium including a pair of electroconductive layers, at least one of which is light-transmissive and which are opposed each other to form a cell; and a dispersion contained in the cell, wherein the dispersion includes a colored particulate material having at least one of an acidic group and a basic group; a hydrocarbon solvent; a resin soluble in the hydrocarbon solvent and having at least one of a basic group and an acidic group; and a compound having a nonionic polar group, and wherein when the particulate material has an acidic group, the resin has a basic group, and when the particulate material has a basic group, the resin has an acidic group.