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).
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Patent number: 9046939Abstract: 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: GrantFiled: April 29, 2014Date of Patent: June 2, 2015Assignee: NAN CHANG O-FILM OPTOELECTRONICS TECHNOLOGY LTDInventors: Lothar R. Westerweck, Stephen C. Arnold, John D. Griffith, Heidi L. Hall, Srinivas T. Rao
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Publication number: 20140320410Abstract: 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: ApplicationFiled: April 29, 2014Publication date: October 30, 2014Applicant: DigitalOptics CorporationInventors: Lothar R. Westerweck, Stephen C. Arnold, John D. Griffith, Heidi L. Hall, Srinivas T. Rao
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Patent number: 8711097Abstract: 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: GrantFiled: November 22, 2009Date of Patent: April 29, 2014Assignee: DigitalOptics CorporationInventors: Lothar Westerweck, Stephen C. Arnold, John D. Griffith, Heidi L. Hall, Srinivas T. Rao
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Publication number: 20110122060Abstract: 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: ApplicationFiled: November 22, 2009Publication date: May 26, 2011Inventors: Lothar Westerweck, Stephen C. Arnold, John D. Griffith, Heidi L. Hall, Srinivas T. Rao
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Patent number: 4877690Abstract: A magnetic optical recording element including a rare earth-transition metal recording layer, a barrier layer and a self-passivating active metal layer.Type: GrantFiled: March 1, 1989Date of Patent: October 31, 1989Assignee: Eastman Kodak CompanyInventors: David A. Glocker, Tukaram K. Hatwar, Gregory Lynn McIntire, Srinivas T. Rao, Douglas G. Stinson
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Patent number: 4875969Abstract: 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: GrantFiled: October 7, 1988Date of Patent: October 24, 1989Assignee: Eastman Kodak CompanyInventors: Kevin Hsu, Srinivas T. Rao, Joseph Y. Kaukeinen
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Patent number: 4824481Abstract: 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: GrantFiled: January 11, 1988Date of Patent: April 25, 1989Assignee: Eaastman Kodak CompanyInventors: Dilip K. Chatterjee, Srinivas T. Rao
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Patent number: 4551212Abstract: 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: GrantFiled: March 11, 1985Date of Patent: November 5, 1985Assignee: RCA CorporationInventors: Srinivas T. Rao, Louis Trager
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Patent number: 4514265Abstract: 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: GrantFiled: July 5, 1984Date of Patent: April 30, 1985Assignee: RCA CorporationInventors: Srinivas T. Rao, Frank Z. Hawrylo
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Patent number: 4445978Abstract: 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: GrantFiled: March 9, 1983Date of Patent: May 1, 1984Assignee: RCA CorporationInventors: James C. Whartenby, Richard Brown, Srinivas T. Rao, Raymond J. Menna
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Patent number: 4424527Abstract: 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: GrantFiled: July 31, 1981Date of Patent: January 3, 1984Assignee: Optical Information Systems, Inc.Inventors: Srinivas T. Rao, Jeoffrey Mott