Patents Assigned to Evans & Sutherland Computer Corporation
  • Publication number: 20040175081
    Abstract: A method for adjusting the wavelength and dominant mode of a laser fiber prior to installation in a laser assembly includes the steps of linearly stretching the laser fiber so as to modify its output wavelength, axially twisting the laser fiber so as to modify its dominant mode, and affixing the laser fiber to a laser assembly in its linearly stretched and axially twisted condition. The laser assembly includes a dynamic tuning mechanism for wavelength adjustment during use. The twisted and stretched fiber has an unadjusted wavelength and dominant mode that are within a selected range before adjustment by the dynamic tuning mechanism.
    Type: Application
    Filed: March 6, 2003
    Publication date: September 9, 2004
    Applicant: Evans & Sutherland Computer Corporation
    Inventors: Jeannie DeWitte, Yuri Grapov, David Owen, Dennis Elkins, Aaron McAllister, Allen Tanner
  • Patent number: 6788307
    Abstract: A device for improving pixel rendering performance in a computer graphics system. The device includes a pixel resolution buffer containing a plurality of pixel storage locations to store pixel values. A depth value is provided for each pixel storage location in the pixel resolution buffer, to store a closest depth for polygons that cover the pixel. A subpixel resolution buffer is also included with a least two subpixels corresponding to each pixel storage location in the pixel resolution buffer.
    Type: Grant
    Filed: April 9, 2002
    Date of Patent: September 7, 2004
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: Terrence J. Coleman, Ken George
  • Patent number: 6788304
    Abstract: A procedural solid texturing system which uses a parameterized function capable of reproducing the most common procedural solid textures, specifically wood, marble, clouds and fire (32). This model is simple enough to be implemented in hardware, and can be realized in VLSI with as little as 100,000 gates. The invention also includes a method for antialiasing the parameterized procedural textures (34, 36). The antialiasing includes an expression for the necessary box filter width, a technique for efficiently box filtering the procedural texture by either MIP mapping the color table or using a summed area color table (38).
    Type: Grant
    Filed: December 5, 2000
    Date of Patent: September 7, 2004
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: John C. Hart, Stephen A. Tibbitts, Terrence J. Coleman
  • Publication number: 20040156088
    Abstract: A communications transmitter is disclosed that utilizes a grating light valve (GLV) to impose information on an optical signal. The communications transmitter further includes at least one laser light source, a frequency dispersing device, an electrostatic modulator that serves as a GLV, and at least one data input source. The laser light source is configured to produce a light beam having a specific optical bandwidth and the frequency dispersing device is optically coupled to the light source and configured to disperse the light beam to produce a frequency dispersed light. The electrostatic modulator includes an electrostatically responsive reflective ribbon oriented to receive a portion of the frequency dispersed light having a specified bandwidth.
    Type: Application
    Filed: February 6, 2003
    Publication date: August 12, 2004
    Applicant: Evans & Sutherland Computer Corporation
    Inventor: Allen H. Tanner
  • Publication number: 20040145708
    Abstract: A device for the passive conversion of one format to another includes: red, blue and green laser light sources and at least one infrared laser light source, at least one line converter configured to produce a fan of light, at least one movable lens configured to collimate the fan of light, and at least one array of light modulators placed such that the collimated light is incident on a portion of the light modulators. Vertical pixels of an input image are reproduced on either 1, 2, 3, etc, adjacent light modulators depending on the target image size to produce a modulated light column. Any discrepancy between the modulated light column height and the target image height is compensated for using a zoom lens. The modulated light column is then reflected to a display surface. An entire image is produced by changing the state of the array of light modulators to correspond with each of the vertical columns of the image and sweeping the vertical columns across the display surface.
    Type: Application
    Filed: January 24, 2003
    Publication date: July 29, 2004
    Applicant: Evans & Sutherland Computer Corporation
    Inventors: Allen H. Tanner, Dennis F. Elkins, Alan R. Hammond, Aaron McAllister
  • Patent number: 6763042
    Abstract: A method and device for the nonlinear combination of laser light which produces a beam of uniform intensity, high spatial purity, and high conversion efficiency. The method includes emitting a laser light from a tunable distributed feedback fiber laser having both thermal and piezoelectric control elements which produces a laser light at a given frequency, wavelength, and intensity; converting the laser light in a nonlinear resonator which uses a nonlinear optical crystal for frequency conversion or mixing; and measuring the resonant frequency of the nonlinear resonator and adjusting the laser light frequency using both the thermal and piezoelectric elements of the fiber laser light source to match the resonant frequency conditions within the nonlinear resonator.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: July 13, 2004
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: Forrest L. Williams, Yuri S. Grapov, Dennis F. Elkins, Allen H. Tanner
  • Patent number: 6760036
    Abstract: A method for extending the data width of a graphics processing channel in a computer graphics system. The method includes the first step of providing a plurality of graphics processing channels having pre-defined output data widths or capacities. The next step is combining at least a portion of an output from at least two of the plurality of graphics processing channels. Another step is defining at least one extended graphics processing channel with an extended data width. The extended graphics processing channel is formed with output portions from the plurality of graphics processing channels.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: July 6, 2004
    Assignee: Evans & Sutherland Computer Corporation
    Inventor: Reed P. Tidwell
  • Patent number: 6751001
    Abstract: A device for the passive conversion of one format to another includes: a laser light source at a predetermined frequency, a line converter configured to produce a fan of light, a movable lens configured to collimate the fan of light, and an array of light modulators placed such that the collimated light is incident on a portion of the light modulators. Vertical pixels of an input image are reproduced on either 1, 2, 3, etc, adjacent light modulators depending on the target image size to produce a modulated light column. Any discrepancy between the modulated light column height and the target image height is compensated for using a zoom lens. The modulated light column is then reflected to a display surface. An entire image is produced by changing the state of the array of light modulators to correspond with each of the vertical columns of the image and sweeping the vertical columns across the display surface.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: June 15, 2004
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: Allen H. Tanner, Aaron S. McAllister
  • Publication number: 20040098236
    Abstract: A system and method is provided for modeling a world database that is a spheroid in a computer graphics simulation system. The method includes the operation of modeling the world database using a plurality of geodetic terrain gridposts. A further operation is creating a triangulated network mesh based on the geodetic terrain gridposts in real-time as a function of eye position. In addition, the triangulated network mesh is stored in geodetic coordinates. The triangulated network mesh is then rendered using geometry formed by the triangulated network mesh.
    Type: Application
    Filed: July 18, 2003
    Publication date: May 20, 2004
    Applicant: Evans & Sutherland Computer Corporation
    Inventors: Neal L. Mayer, Michael A. Cosman, Robert C. Dawson, Heber B. Bennion
  • Patent number: 6711187
    Abstract: A rapidly oscillating laser light source is produced that exhibits extended pulse duration having a substantially uniform amplified output. A pulsed beam of laser light having a given wavelength, frequency, duration and intensity is produced such that the pulse shape is controlled. The pulsed beam is amplified using a fiber amplifier which exhibits inherent changes in amplifier gain at the frequencies of interest. The fiber amplifier is continuously pumped. A feedback signal is provided with the amplified pulse characteristics and is used to adjust the pulse shape of the pulsed beam of laser light before amplifying, such that the intensity is changed over the pulse duration to generate a substantially uniform amplified output during each pulse.
    Type: Grant
    Filed: April 22, 2002
    Date of Patent: March 23, 2004
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: Allen H. Tanner, Dennis F. Elkins, Cameron C. Farmer, Yuri S. Grapov
  • Patent number: 6603482
    Abstract: A method for using the alpha channel to generate screen space effects in a high fidelity, real time, computer graphics simulation system. The first step is providing a rendering engine with an alpha processing channel, a frame buffer that includes an alpha memory, and a post processor. Next, screen effect data is processed through the alpha channel. The third step is storing screen effect data in the alpha buffer memory. Then the screen effect data is applied to the frame buffer color data using the post processor. The primary screen effects that are desired to be generated through the alpha channel are double buffered overlays, accurate night scene rendering and edge blending attenuation at channel boundaries. Night scene rendering features include range attenuated slewable own-ship light lobes, non-attenuation of point lights and luminous polygons, and ambient lighting.
    Type: Grant
    Filed: January 31, 2000
    Date of Patent: August 5, 2003
    Assignee: Evans & Sutherland Computer Corporation
    Inventor: Reed P. Tidwell
  • Patent number: 6600854
    Abstract: A system and method for polishing an optical fiber with a polishing lap. The system comprises a substrate, an optical fiber disposed on the substrate so as to be outwardly curved, and an electrical conductor disposed over the outward curve of the optical fiber. A voltage source is connected to the electrical conductor, and the polishing lap is configured to initially abrade the electrical conductor to cause severance thereof. The position of the polishing lap when the electrical conductor is severed represents a reference point approximately indicating the surface of the optical fiber. A detector connected to the electrical conductor detects a change in voltage therein, indicating severance of the electrical conductor, and subsequently monitors the polishing depth relative to the reference point.
    Type: Grant
    Filed: March 5, 2001
    Date of Patent: July 29, 2003
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: Jesse Anderegg, Bret Winkler, Allen Tanner
  • Patent number: 6574352
    Abstract: A method for anticipation and tracking eye movement for head tracked projectors which divides a projection surface into spherical triangles and uses interpolating calibration values stored at each vertex of the triangle. A calibration map is used that contains information about the relationship between the user's head orientation and where they are looking with their eyes at each calibration point. The projection surface is divided into spherical triangles which are searched to find the triangle which contain the user's interpolated view point by performing a dot product test between the interpolated view point and the unit normal vectors inside the three planes that make up the sides of the spherical triangle extended back to the eye point. When a dot product test fails for any side of the triangle the pointer is followed to the adjacent triangle where the test starts over.
    Type: Grant
    Filed: May 18, 1999
    Date of Patent: June 3, 2003
    Assignee: Evans & Sutherland Computer Corporation
    Inventor: Philip Skolmoski
  • Patent number: 6525740
    Abstract: A system and method for antialiasing bump texture and bump mapping which overcomes the disadvantages of previous methods of antialiasing bump maps without significantly expanding the required physical hardware needed for the calculations. A bump curvature value computed from the difference in heights between adjacent texels is applied to the specular shading calculations for bump maps. The bump curvature is used to open an “integration window” over the specular highlight of the bump. The resulting integral provides a highlight value which approximates the specular highlight. The highlight value is then added to the pixel shading value in the frame buffer. The process decreases the brightness of the highlights while increasing the overall brightness near the highlights, in a user-controlled blend that preserves the proper average effect of the specularity or reflectiveness. The process has no effect where there are no bumps or where the viewer is so close to the surface.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: February 25, 2003
    Assignee: Evans & Sutherland Computer Corporation
    Inventor: Michael A. Cosman
  • Patent number: 6496160
    Abstract: An apparatus for converting analog stroke display signals representing electron beam generated stroke traces into raster display information for producing a raster-scan image display. The apparatus includes a sampling circuit for sampling the analog stroke display signals to produce pixel data representing sub-pixel locations covered by the stroke traces. A frame buffer is coupled to the sampling circuit to temporarily store pixel data. A filter is coupled to the frame buffer for calculating brightness of pixels based upon the amount of coverage of the pixels by a stroke trace. In addition, a raster-scan display device is coupled to the filter for receiving the pixel data from the filter to produce a raster-scan image.
    Type: Grant
    Filed: April 29, 1999
    Date of Patent: December 17, 2002
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: Allen H. Tanner, Calvin L. Simmons
  • Patent number: 6473090
    Abstract: A method for MIP mapping index texture. This invention has index texture with texel index values which refer to physical material properties. First, a lookup table is stored and the lookup table has table entries defining material types. Each table entry has an index, and material property type values. Then at least two texels are selected from the index texture, where each texel has index values corresponding to table entries. Next, the material property type values are averaged for each separate property type from the table entries for the selected texels. This produces an average material property value for each material property type. Another step is selecting a new material index based on the material which most closely matches the average material property values. The final step is generating the next lowest MIP level by using the new material indexes to form a new index texture with fewer texels.
    Type: Grant
    Filed: November 3, 1999
    Date of Patent: October 29, 2002
    Assignee: Evans & Sutherland Computer Corporation
    Inventor: Neal L. Mayer
  • Patent number: 6437789
    Abstract: A method and apparatus for accessing a cache memory of a computer graphics system, the apparatus including a frame buffer memory having a graphics memory for storing pixel data for ultimate supply to a video display device, a read cache memory for storing data received from the graphics memory, and a write cache memory for storing data received externally of the frame buffer and data that is to be written into the graphics memory. Also included is a frame buffer controller for controlling access to the graphics memory and read and write cache memories. The frame buffer controller includes a cache first in, first out (FIFO) memory pipeline for temporarily storing pixel data prior to supply thereof to the cache memories.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: August 20, 2002
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: Reed Tidwell, Gary Pimentel
  • Patent number: 6433840
    Abstract: A method for anticipation and tracking eye movement for head tracked projectors which divides a projection surface into spherical triangles and uses interpolating calibration values stored at each vertex of the triangle. A calibration map is used that contains information about the relationship between the user's head orientation and where they are looking with their eyes at each calibration point. The projection surface is divided into spherical triangles which are searched to find the triangle which contain the user's interpolated view point by performing a dot product test between the interpolated view point and the unit normal vectors inside the three planes that make up the sides of the spherical triangle extended back to the eye point. When a dot product test fails for any side of the triangle the pointer is followed to the adjacent triangle where the test starts over.
    Type: Grant
    Filed: July 22, 1999
    Date of Patent: August 13, 2002
    Assignee: Evans & Sutherland Computer Corporation
    Inventor: Kenneth A. Poppleton
  • Patent number: 6404425
    Abstract: A method for creating a span-based multisample Z-buffer pixel processor in a computer graphics system to thereby reduce a quantity of data that must be stored for each pixel in a frame buffer thereof. By taking advantage of areal coherence, the quantity of data that must be stored in each pixel is reduced. By employing merging, the method is also able to ensure than pixel storage requirements do not grow beyond a predetermined limit.
    Type: Grant
    Filed: January 11, 1999
    Date of Patent: June 11, 2002
    Assignee: Evans & Sutherland Computer Corporation
    Inventor: Michael Cosman
  • Patent number: 6362818
    Abstract: This invention relates generally to the field of computer graphics display, and more particularly to reducing the amount of time needed to render complex virtual scenes on a computer graphics display. This invention combines the advantages of the prior art methods of list priority and depth buffering (e.g. Z-buffering) with new simplified and enhanced full buffer processes. In one embodiment, a simplified full buffer arrangement enables the elimination of rendering primitives prior to pixel shading for regions of the screen which have previously been covered by closer primitives. Another embodiment provides for an enhanced full buffer that combines the coverage of a previously rendered primitive in a partial buffer and associates it with a current primitive to cover pixel arrays.
    Type: Grant
    Filed: February 24, 1999
    Date of Patent: March 26, 2002
    Assignee: Evans & Sutherland Computer Corporation
    Inventors: Harold D. Gardiner, Russell J. Urry