Patents Represented by Attorney, Agent or Law Firm William Propp
  • Patent number: 6496215
    Abstract: A heating element adjusts the curvature of a cylindrical wobble correction mirror to compensate and correct the scan line bow for an optical scanner. A current applied through the heating element along one side of the mirror will cause the mirror to bend vertically for a horizontal beam to adjust the scan line bow for a single beam and approximately equalize the scan line bow for multiple beams.
    Type: Grant
    Filed: December 15, 2000
    Date of Patent: December 17, 2002
    Assignee: Xerox Corporation
    Inventor: James M. Wilson
  • Patent number: 6496526
    Abstract: A laser driver uses a switch, a current mirror, a control transistor and two current generators to control the ON and bias currents in a laser diode. In the bias mode the current from one generator is shared by one half of the current mirror and the adjustable control transistor. The other current generator then drives the other half of the mirror circuit and the laser diode in parallel, resulting in the laser diode getting the same amount of current that the control transistor gets. In the ON mode, the switch cuts off the first half of the current mirror, which is mirrored in the other half, so that all of the other generator current is used in the laser diode. The current drivers are adjustable to the ON current and the control transistor current is adjustable to the bias current.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: December 17, 2002
    Assignee: Xerox Corporation
    Inventor: Harry J. McIntyre
  • Patent number: 6483530
    Abstract: A honeycomb structure is formed integral with a raster output scanning system housing. A constrained layer damper is bonded to the honeycomb structure and the raster output scanning system is mounted on the constrained layer damper. The honeycomb structure and constrained layer damper provide support and reduce vibrations to the raster output scanning system. The cells of the honeycomb structure can be irregular in height, thickness, density or shape to further support and damp vibrations.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: November 19, 2002
    Assignee: Xerox Corporation
    Inventor: James M. Wilson
  • Patent number: 6480515
    Abstract: A fluid-filled heat sink is positioned on the emission surface of a laser diode. The light beam emitted by the laser diode aperture will propagate though the optically transparent fluid to be transmitted through an output window of the heat sink. Heat generated by the laser diode will be transferred by the thermally conductive fluid to the heat sink housing which will radiate the heat or transfer the heat to a secondary heat sink.
    Type: Grant
    Filed: December 15, 2000
    Date of Patent: November 12, 2002
    Assignee: Xerox Corporation
    Inventor: James M. Wilson
  • Patent number: 6455340
    Abstract: A method is provided for fabricating a nitride based resonant cavity semiconductor structure with a first distributed Bragg reflector on a sapphire substrate, a second substrate bonded to the first distributed Bragg reflector, the sapphire substrate removed by laser-assisted epitaxial lift-off, and fabricating a second Bragg reflector on the semiconductor structure opposite the first distributed Bragg reflector. The nitride based resonant cavity semiconductor structure can be a VCSEL, LED or photodetector, or a combination of said devices.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: September 24, 2002
    Assignee: Xerox Corporation
    Inventors: Christopher L. Chua, Michael A. Kneissl, David P. Bour
  • Patent number: 6407867
    Abstract: A beam splitter cube and two roof mirrors are used as a beam spacer to interlace and closely space four parallel laser beams.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: June 18, 2002
    Assignee: Xerox Corporation
    Inventor: Michael Hildebrandt
  • Patent number: 6400512
    Abstract: A six sided refractive / reflective optical element controls the separation between four parallel laser beams. Two beams will be reflected off the optical element and two beams will be refracted within the optical element with each reflection and refraction being off a different side of the optical element to form four closely spaced parallel light beams.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: June 4, 2002
    Assignee: Xerox Corporation
    Inventor: Michael Hildebrandt
  • Patent number: 6381073
    Abstract: A segmented mirror with alternating reflective and transmissive surfaces and a refractive tilt place which laterally displaces two parallel beams are used as a beam spacer. A first beam is reflected by the segmented mirror and a second beam is transmitted by the segmented mirror. A third beam is refracted and laterally displaced by the tilt plate then reflected by the segmented mirror while a fourth beam is beam is refracted and laterally displaced by the tilt plate then transmitted by the segmented mirror. The segmented mirror and the refractive tilt plate closely space four parallel laser beams.
    Type: Grant
    Filed: December 5, 2000
    Date of Patent: April 30, 2002
    Assignee: Xerox Corporation
    Inventor: James M. Wilson
  • Patent number: 6381209
    Abstract: The multi-channel optical head for recording and reading optical storage data has a write laser array for generating a plurality of write beams and a read laser array for generating a plurality of read beams. The write beams and the read beams share a common optical path with a first broadband non-polarizing beam splitter which directs the beams towards the optical recording medium or to a power detector and with a second broadband non-polarizing beam splitter which directs the write beams and the read beams to the optical recording medium and which directs the read beams, after retroreflection and information modulation from the optical recording medium, to be split by a beam splitter and focused onto a detector to provide focusing information and another detector which detects its intensity to read data and provides tracking information.
    Type: Grant
    Filed: September 28, 1999
    Date of Patent: April 30, 2002
    Assignee: Xerox Corporation
    Inventors: Russell B. Rauch, Mark Shi Wang
  • Patent number: 6373809
    Abstract: The multi-channel optical head for recording and reading optical storage data has a write laser array for generating a plurality of write beams and a read laser array for generating a plurality of read beams. The write beams and the read beams share a common optical path with a first broadband non-polarizing beam splitter which directs the beams towards the optical recording medium or to a power detector and with a second broadband non-polarizing beam splitter which directs the write beams and the read beams to the optical recording medium and which directs the read beams, after retroreflection and information modulation from the optical recording medium, to be split by a beam splitter and focused onto a detector to provide focusing information and another detector which detects its intensity to read data and provides tracking information.
    Type: Grant
    Filed: September 28, 1999
    Date of Patent: April 16, 2002
    Assignee: Xerox Corporation
    Inventors: Russell B. Rauch, Mark Shi Wang
  • Patent number: 6301054
    Abstract: A refractive optical element provides beam separation control for two or four light beams by refracting each beam from an incident surface through the optical element to be refracted from a parallel exit surface out of the optical element. The beams have closer beam to beam spacing after the refraction from the optical element than before. The incident and exit surfaces are angled relative to and symmetric around an optical axis.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: October 9, 2001
    Assignee: Xerox Corporation
    Inventor: Chuong Van Tran
  • Patent number: 6292285
    Abstract: A single rotating polygon mirror with v-shaped facets having upper and lower reflective facet surfaces reflects and separates dual beams to two photoreceptors in a ROS. Each facet surface will have a different tilt angle. The two independently modulated beams will share common optical elements between the light sources and the mirror and may share a common f-theta scan lens. Two sets of two beams can be incident upon the facets on opposite sides of the rotating polygon mirror. The polygon mirror facet can also have three or four reflective facet surfaces to reflect and separate three or four independently modulated beams to three or four different photoreceptors.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: September 18, 2001
    Assignee: Xerox Corporation
    Inventors: Mark Shi Wang, Vinod Mirchandani
  • Patent number: 6282220
    Abstract: An infrared laser structure is stacked on top of a red laser structure with both having an inverted or p-side down orientation. The red/infrared stack laser structure is inverted and wafer fused to a blue laser structure to form a red/infrared/blue monolithic laser structure. The top semiconductor layer of the inverted red/infrared stack laser structure is a GaInP fusion bonding layer which will be wafer fused to the top semiconductor layer of the blue laser structure which is a GaN cladding/contact layer.
    Type: Grant
    Filed: June 27, 2000
    Date of Patent: August 28, 2001
    Assignee: Xerox Corporation
    Inventor: Philip D. Floyd
  • Patent number: 6252695
    Abstract: Two shorter focal length wobble correction optical elements reduce the height of a raster output scanning (ROS) system. The wobble correction optical elements can be two lenses or two mirrors.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: June 26, 2001
    Assignee: Xerox Corporation
    Inventor: James M. Wilson
  • Patent number: 6238944
    Abstract: The barrier layers within a quantum well active region of a vertical cavity surface emitting laser can be silicon doped. Under thermal annealing, the silicon doped barrier layers will form disordered regions of the quantum well active region around the remaining non-disordered regions of the quantum well active region. The disordered regions of the quantum well active region will prevent diffusion of injected carriers from the non-disordered, light emitting quantum well active region.
    Type: Grant
    Filed: December 21, 1999
    Date of Patent: May 29, 2001
    Assignee: Xerox Corporation
    Inventor: Philip D. Floyd
  • Patent number: 6185241
    Abstract: An annular metal layer is provided between a conductive oxide layer and a dielectric mirror in a vertical cavity surface emitting laser. The annular metal layer defines the output window for the laser cavity which matches the TEM00 fundamental mode of the light beam emitted by the active region of the VCSEL. The metal layer outside the output window provides modal reflectivity discrimination against high order transverse modes of the light beam emitted by the active region of the VCSEL.
    Type: Grant
    Filed: October 29, 1998
    Date of Patent: February 6, 2001
    Assignee: Xerox Corporation
    Inventor: Decai Sun
  • Patent number: 6178031
    Abstract: The pixel clock of a raster output scanning (ROS) system modulates an emitted light beam to provide pixel placement along a scan line. A method calculates the pixel clock frequency shifts to correct non-linearity of the scan line in a ROS. A data smoothing polynomial is calculated for the non-linearity of the pixels along the scan line. The needed frequency shift based on the polynomial to the first or higher orders is calculated and stored in a frequency shift look-up table. The calculated frequency shift from the frequency shift lookup table modifies the nominal pixel clock frequency to correct for the measured scan linearity of the ROS by modulation of the light beam.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: January 23, 2001
    Assignee: Xerox Corporation
    Inventors: Russell B. Rauch, Mohammad H. Rahnavard
  • Patent number: 6169623
    Abstract: A raster output scanner is disclosed which utilizes a collimator assembly which can be replaced at the field. The collimator assembly is mounted on a raster output housing. Both the raster output housing and the collimator assembly have securing means to secure the collimator assembly to the raster output scanner housing. The raster output scanner housing and the collimator assembly are designed to provide automatic adjustment for the light beam exiting from the collimator assembly with the optical path within the ROS housing once the collimator assembly is secured to the raster output scanner housing.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: January 2, 2001
    Assignee: Xerox Corporation
    Inventors: Vincent W. AuYeung, Khuay Cam, Nancy L. Brunsdon-Veloz
  • Patent number: 6167074
    Abstract: A monolithic laser structure has an infrared laser structure side by side with a red laser structure. The infrared and red laser structures share the same substrate and have the same material for the cladding layers and for the cap and barrier reduction layers. The red and infrared laser structures can have native oxide confined or metal confined ridge waveguides.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: December 26, 2000
    Assignee: Xerox Corporation
    Inventors: Decai Sun, Ross D. Bringans
  • Patent number: 6160833
    Abstract: The present invention provides an independently addressable, vertical cavity surface emitting laser ("VCSEL") in the blue wavelength range of 390 to 430 nanometers. The gallium nitride-based laser structure is grown by selective area epitaxy and lateral mask overgrowth. By appropriate patterning of a dielectric mask on the gallium nitride layer on a sapphire substrate, areas in a second gallium nitride layer can have a low defect density upon which the remainder of the laser structure can be formed.
    Type: Grant
    Filed: May 6, 1998
    Date of Patent: December 12, 2000
    Assignee: Xerox Corporation
    Inventors: Philip D. Floyd, Daniel Hofstetter