Patents by Inventor Srinivas T. Rao

Srinivas T. Rao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9046939
    Abstract: An optical navigation device that can sense the movement of an object, such as a user's finger, so that the movement can control a feature of a consumer digital device such as a cursor on a display screen. The device includes a substrate to which an LED, reflector, and image sensor are attached. Light from the LED is directed by the elliptical reflector toward and through a window that is transparent to the light from the LED and then is reflected off of the user's finger back through the window, through a lens, and onto the image sensor. The reflector is positioned to direct light toward the window at an oblique angle, in the range of 65 to 70 degrees from an angle normal to the window. Further, the reflector is curved to gather light across a large solid angle in the vicinity of the LED. The curved shape of the reflector may be a portion of an ellipsoid and the LED may be located at one of the foci of the ellipsoid, with the window located at the other foci of the ellipsoid.
    Type: Grant
    Filed: April 29, 2014
    Date of Patent: June 2, 2015
    Assignee: NAN CHANG O-FILM OPTOELECTRONICS TECHNOLOGY LTD
    Inventors: Lothar R. Westerweck, Stephen C. Arnold, John D. Griffith, Heidi L. Hall, Srinivas T. Rao
  • Publication number: 20140320410
    Abstract: An optical navigation device that can sense the movement of an object, such as a user's finger, so that the movement can control a feature of a consumer digital device such as a cursor on a display screen. The device includes a substrate to which an LED, reflector, and image sensor are attached. Light from the LED is directed by the elliptical reflector toward and through a window that is transparent to the light from the LED and then is reflected off of the user's finger back through the window, through a lens, and onto the image sensor. The reflector is positioned to direct light toward the window at an oblique angle, in the range of 65 to 70 degrees from an angle normal to the window. Further, the reflector is curved to gather light across a large solid angle in the vicinity of the LED. The curved shape of the reflector may be a portion of an ellipsoid and the LED may be located at one of the foci of the ellipsoid, with the window located at the other foci of the ellipsoid.
    Type: Application
    Filed: April 29, 2014
    Publication date: October 30, 2014
    Applicant: DigitalOptics Corporation
    Inventors: Lothar R. Westerweck, Stephen C. Arnold, John D. Griffith, Heidi L. Hall, Srinivas T. Rao
  • Patent number: 8711097
    Abstract: An optical navigation device that can sense the movement of an object, such as a user's finger, so that the movement can control a feature of a consumer digital device such as a cursor on a display screen. The device includes a substrate to which an LED, reflector, and image sensor are attached. Light from the LED is directed by the elliptical reflector toward and through a window that is transparent to the light from the LED and then is reflected off of the user's finger back through the window, through a lens, and onto the image sensor. The reflector is positioned to direct light toward the window at an oblique angle, in the range of 65 to 70 degrees from an angle normal to the window. Further, the reflector is curved to gather light across a large solid angle in the vicinity of the LED. The curved shape of the reflector may be a portion of an ellipsoid and the LED may be located at one of the foci of the ellipsoid, with the window located at the other foci of the ellipsoid.
    Type: Grant
    Filed: November 22, 2009
    Date of Patent: April 29, 2014
    Assignee: DigitalOptics Corporation
    Inventors: Lothar Westerweck, Stephen C. Arnold, John D. Griffith, Heidi L. Hall, Srinivas T. Rao
  • Publication number: 20110122060
    Abstract: An optical navigation device that can sense the movement of an object, such as a user's finger, so that the movement can control a feature of a consumer digital device such as a cursor on a display screen. The device includes a substrate to which an LED, reflector, and image sensor are attached. Light from the LED is directed by the elliptical reflector toward and through a window that is transparent to the light from the LED and then is reflected off of the user's finger back through the window, through a lens, and onto the image sensor. The reflector is positioned to direct light toward the window at an oblique angle, in the range of 65 to 70 degrees from an angle normal to the window. Further, the reflector is curved to gather light across a large solid angle in the vicinity of the LED. The curved shape of the reflector may be a portion of an ellipsoid and the LED may be located at one of the foci of the ellipsoid, with the window located at the other foci of the ellipsoid.
    Type: Application
    Filed: November 22, 2009
    Publication date: May 26, 2011
    Inventors: Lothar Westerweck, Stephen C. Arnold, John D. Griffith, Heidi L. Hall, Srinivas T. Rao
  • Patent number: 4877690
    Abstract: A magnetic optical recording element including a rare earth-transition metal recording layer, a barrier layer and a self-passivating active metal layer.
    Type: Grant
    Filed: March 1, 1989
    Date of Patent: October 31, 1989
    Assignee: Eastman Kodak Company
    Inventors: David A. Glocker, Tukaram K. Hatwar, Gregory Lynn McIntire, Srinivas T. Rao, Douglas G. Stinson
  • Patent number: 4875969
    Abstract: A method is disclosed for making a fiber optic array for use in an optical scanning device. The array includes a substrate and a plurality of optical fibers arranged on the substrate to form a linear array of the fibers. Each of the fibers is received in grooves in the substrate to precisely space the fibers relative to each other. Each of the fibers is adapted to receive light from a source such as a laser diode. In order to increase the packing density of the fibers in the array, the fibers are mounted in sets of parallel grooves which are spaced to draw the fibers closer together at an output end. Further, the ends of the fibers are etched to decrease the cladding diameter and thereby permit the fiber ends to be more closely spaced relative to each other.
    Type: Grant
    Filed: October 7, 1988
    Date of Patent: October 24, 1989
    Assignee: Eastman Kodak Company
    Inventors: Kevin Hsu, Srinivas T. Rao, Joseph Y. Kaukeinen
  • Patent number: 4824481
    Abstract: Sputtering targets are made by melting at least one rare earth and at least one transition metal to produce an amorphous alloy melt, forming a powder of the alloy in an oxygen free atmosphere, introducing the powdered alloy into a reducing mold, adding a layer of powdered oxygen-getter on top of the powdered alloy, and hot pressing the alloy.
    Type: Grant
    Filed: January 11, 1988
    Date of Patent: April 25, 1989
    Assignee: Eaastman Kodak Company
    Inventors: Dilip K. Chatterjee, Srinivas T. Rao
  • Patent number: 4551212
    Abstract: It has been found that an additive comprising a mixture of phenazine dyestuffs in the combination from about 30 to 40 percent by weight of (a) a Janus Green B type dyestuff or a mixture thereof and (b) from about 70 to 60 percent by weight of Safranine T, when added to an aqueous acidic copper sulfate bath in the amount of about 0.03 to about 0.10 gram per liter of the bath, deposits copper consistently with the required properties for micromachining.
    Type: Grant
    Filed: March 11, 1985
    Date of Patent: November 5, 1985
    Assignee: RCA Corporation
    Inventors: Srinivas T. Rao, Louis Trager
  • Patent number: 4514265
    Abstract: An improved process for electroplating bonding pads, such as of gold, onto semiconductor devices is disclosed. Upon electrically connecting a masked semiconductor body and a suitable anode to the negative and positive terminals respectively of a power supply and submerging the wafer and anode into a suitable electrolyte, a modulated, rather than direct, current is applied to the electrolyte. A low stress, fine grain bonding pad layer is provided and, unexpectedly, non-planarities in the semiconductor body surface having a depth of about 1-3 microns can be substantially planarized when the thickness of the layer deposited is about 6-8 microns or more.
    Type: Grant
    Filed: July 5, 1984
    Date of Patent: April 30, 1985
    Assignee: RCA Corporation
    Inventors: Srinivas T. Rao, Frank Z. Hawrylo
  • Patent number: 4445978
    Abstract: A method is provided for fabricating a via connector from a first surface of a semiconductor wafer to an opposite second surface of the wafer. The first step consists of forming an adherent metal layer on the first surface on the semiconductor wafer. If the first surface of the semiconductor wafer has electronic components formed thereon, the metal layer is applied over the electronic components and preferably a protective layer of material is formed over the metal layer. Via holes are then laser drilled at predetermined locations through the metal layer and then through the semiconductor wafer. Thereafter a photoresist layer is applied over the first surface and exposed and developed to provide passage holes in the photoresist which are in alignment with the laser drilled apertures. The metal layer is then connected in the cathode position of the electroforming apparatus and via connectors are thereafter electroformed in the via holes.
    Type: Grant
    Filed: March 9, 1983
    Date of Patent: May 1, 1984
    Assignee: RCA Corporation
    Inventors: James C. Whartenby, Richard Brown, Srinivas T. Rao, Raymond J. Menna
  • Patent number: 4424527
    Abstract: The invention is directed to a bonding pad metallization for stress sensitive semiconductor devices such as semiconductor lasers or the like. An attendant advantage is a diffusion barrier layer which inhibits the migration of conventional bonding materials such as indium solder.
    Type: Grant
    Filed: July 31, 1981
    Date of Patent: January 3, 1984
    Assignee: Optical Information Systems, Inc.
    Inventors: Srinivas T. Rao, Jeoffrey Mott