Patents by Inventor Robert C. Keller

Robert C. Keller 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: 6697184
    Abstract: An optical system 200 includes a light source 202, such as a laser diode. A rotatable mirror 208 is positioned to receive a light beam 220 from the light source 202. A collimating lens 218 is positioned to receive a reflected light beam 222 from the rotatable mirror 208. The collimating lens 218 preferably has a focal length that is about equal to the sum of the distance between the light source 202 and the mirror 208 and the mirror 208 and the lens 218.
    Type: Grant
    Filed: January 29, 2002
    Date of Patent: February 24, 2004
    Assignee: Texas Instruments Incorporated
    Inventors: Robert C. Keller, Luisa Angelica Zepeda
  • Publication number: 20020070335
    Abstract: A packaged micromirror assembly (21, 21′) is disclosed. The assembly (21, 21′) includes a mirror element (41) having a mirror surface (29) that can rotate in two axes. Magnets (53) are attached to the mirror element (41), to permit rotation of the mirror surface (29) responsive to the energizing of coil drivers (36). A sensor (63, 80) is disposed under the mirror surface (29) to detect mirror orientation. In one aspect of the invention, the sensor (63) includes a light source such as an LED (68) that imparts light through an aperture (66) at the underside of the mirror surface (29). Light detectors (65) are arranged at varying angles, and detect relative intensity of light reflected from the underside of the mirror surface (29), from which the rotational position of the mirror (29) can be derived. According to another aspect of the invention, a conical sensor (80) with multiple insulated segmented capacitor plates are arranged under the mirror surface (29).
    Type: Application
    Filed: September 20, 2001
    Publication date: June 13, 2002
    Inventors: John W. Orcutt, Robert C. Keller, Jose L. Melendez, Dwight Bartholomew
  • Publication number: 20020054412
    Abstract: A cellular optical wireless network 10 includes multiple bi-directional point-to-point links between a central hub 12 and dispersed clients 14. When the hub 14 is limited in size, the receivers may be in close proximity to one another. In this case, the optical signal from two or more clients, which may have spread significantly in diameter due to angular spread in the transmitted light, may overlap spatially at the hub, causing interference and difficulty in separating the data. The present invention provides techniques to avoid such interference.
    Type: Application
    Filed: April 20, 2001
    Publication date: May 9, 2002
    Inventors: Robert C. Keller, Jose L. Melendez
  • Publication number: 20020033981
    Abstract: An optical communication transmitter (13), receiver (15), and transceiver (17) having distinctive retro-reflective elements (30) and/or reflectivity that can be modulated. In one embodiment, the retro-reflective elements (30) can have different shapes or patterns (32), irrespective of rotation or size. In another embodiment, the retro-reflective elements can have their reflectivity modulated (42) to have a distinctive pattern in time. The solution also provides the capability to direct a remote optical receiver (15) to an available port (17) with an appropriate FOV. In the case where retro-reflective elements are only shape distinctive, a method may be used to direct the remote OWLink (15) to an appropriate port (17) of the hub (54). In addition to the hub ports (17) used for data links, additional hub ports called command ports (60) are added that are only used during the initial link setup of remote units. The hub (54) contains enough command ports (60) such that one command port covers each possible FOV.
    Type: Application
    Filed: June 29, 2001
    Publication date: March 21, 2002
    Inventors: Robert C. Keller, Jose Luis Melendez
  • Patent number: 5912456
    Abstract: A surface plasmon resonance sensor includes a light source 10 and a polarizer 18 for producing polarized light which passes through a transparent body 12 and strikes a thin conductive film 26 disposed on the exterior surface of the body 12. The film 26 exhibits surface plasmon resonance when the light strikes the film at a "resonance angle". By determining the angle at which surface plasmon resonance occurs, the refractive index of the material on the side of the film 26 opposite to the side which reflects the polarized light can be measured.
    Type: Grant
    Filed: March 19, 1997
    Date of Patent: June 15, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Jose L. Melendez, Richard A. Carr, Robert C. Keller
  • Patent number: 5898503
    Abstract: A surface plasmon resonance (SPR) sensor includes a transparent base housing 12 and a detachable optical housing 19. Radiation from a radiation source 10, disposed within base housing 12, is polarized by polarizing filter 16 and passes through the interface between base housing 12 and optical housing 19. The polarized radiation 18 is reflected from a mirror 20 onto a SPR layer 22, which is formed on an exterior surface of optical housing 19. Layer 22 comprises a thin layer of a conductive material. Radiation 24 reflected from SPR layer 22 re-enters housing 19 and strikes an array 28 of photodetectors. From the intensity of radiation at each photodetector, one can determine the index of refraction of the substance on the opposite side of SPR layer 22.
    Type: Grant
    Filed: May 5, 1998
    Date of Patent: April 27, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Robert C. Keller, Jose L. Melendez, Richard A. Carr
  • Patent number: 5428099
    Abstract: Elastomers modified by amine groups, particularly diethanol amine, are used for controlling carbon black distribution in elastomer blends.
    Type: Grant
    Filed: May 19, 1993
    Date of Patent: June 27, 1995
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Fred Morrar, Laszlo L. Ban, Walter G. Funk, Edward Kresge, Hsien-Chang Wang, Sudhin Datta, Robert C. Keller
  • Patent number: 5246778
    Abstract: A hose composition is provided which comprises a halogen-containing copolymer of a C.sub.4 to C.sub.7 isomonoolefin and a para-alkylstyrene, fillers, rubber compounding additives and a curing agent. A hose comprising at least a portion made from this hose composition is also provided.
    Type: Grant
    Filed: August 17, 1992
    Date of Patent: September 21, 1993
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Bernard J. Costemalle, Robert C. Keller, Donald F. Kruse, James V. Fusco, Marcel A. Steurs
  • Patent number: 5021509
    Abstract: The present invention provides for an improved butyl rubber composition which exhibits improved adhesion to pre-treated polyester textile materials, while at the same time important physical properties of cured butyl rubber such as modulus, tensile strength and elongation are maintained or even enhanced. The vulcanizable composition of the invention is based on a blend of butyl rubber and minor amounts of a copolymer of ethylene with a lower alkyl acrylate or methacrylate, or a terpolymer of ethylene, a lower alkyl acrylate or methacrylate and acrylic or methacrylic acid. The composition of this invention exhibits improved adhesion to pre-treated polyester textile materials.The invention also relates to laminates of the butyl rubber compositions of this invention with polyester textile materials such as yarns and woven fabrics.
    Type: Grant
    Filed: September 1, 1989
    Date of Patent: June 4, 1991
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Robert C. Keller, Marc R. Kuhnhein
  • Patent number: 4408675
    Abstract: A dual outlet engine exhaust system having a pair of resonators which are joined as a rigid assembly by a resonator manifold which also maintains divided exhaust gas flow to the resonators.
    Type: Grant
    Filed: May 22, 1981
    Date of Patent: October 11, 1983
    Assignee: General Motors Corporation
    Inventor: Robert C. Keller
  • Patent number: D296202
    Type: Grant
    Filed: April 21, 1986
    Date of Patent: June 14, 1988
    Assignee: Carlisle Corporation
    Inventor: Robert C. Keller