Patents by Inventor Thomas M. Marshall

Thomas M. Marshall 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: 6783269
    Abstract: According to this invention, a side-emitting illumination device for uniformly distributing light is composed of an LED light source, a light-transmitting rod which permits total internal reflection, and outcoupling material affixed to an outer surface of the rod. Light enters the rod at one end and travels along the rod by total internal reflection. Light that hits the outcoupling material is angularly distributed based on the width of the outcoupling material.
    Type: Grant
    Filed: December 27, 2000
    Date of Patent: August 31, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Michael D. Pashley, Thomas M. Marshall, Frank J. P. Schuurmans
  • Patent number: 6741351
    Abstract: White light emitting LED luminaire incorporates an array of red, green and blue emitting LEDs and a feedback arrangement to maintain a desired color balance. The feedback arrangement includes photodiodes positioned and enabled to separately measure the light output of each RGB color component. In one embodiment, a single photodiode or array of photodiodes is positioned to intercept reflected light from a partially reflecting element placed in the path of the combined output of the LED array. Individual colors are measured sequentially by pulsing the LEDs and photodiodes or by the use of color filters. In an alternate embodiment, each LED has an associated photodiode, either incorporated into the LED package or in a separate package.
    Type: Grant
    Filed: June 7, 2001
    Date of Patent: May 25, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Thomas M Marshall, Michael D Pashley, Frank J P Schuurmans
  • Patent number: 6726341
    Abstract: A storage compartment is equipped with a light emitting diode (LED) light source for illuminating contents inside the compartment. The LED light source includes a LED light engine outside the compartment and a light guide inside the compartment. The light guide is optically coupled to be LED light engine to bring light from the LED light engine into the compartment for providing illumination inside the compartment. The LED light engine may include red, green, and blue LEDs that contribute to the illumination inside the compartment. Respective outputs of the red, green, and blue LEDs may be separately controllable to allow a variably controlled color point of illumination inside the compartment. Total output of the LED light engine may be controllable to vary intensity of illumination inside the compartment.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: April 27, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Michael D. Pashley, Thomas M. Marshall, Ans Saalberg, Larry McColloch
  • Patent number: 6692136
    Abstract: A hybrid lighting system for producing white light including at least one light emitting diode and phosphor-light emitting diode. The hybrid lighting system exhibits improved performance over conventional LED lighting systems that use LEDs or phosphor-LEDs to produce white light. In particular, the hybrid system of the invention permits different lighting system performance parameters to be addressed and optimized as deemed important, by varying the color and number of the LEDs and/or the phosphor of the phosphor LED.
    Type: Grant
    Filed: November 22, 2002
    Date of Patent: February 17, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman
  • Publication number: 20030076034
    Abstract: A LED chip package including a base, an array of LED chips disposed on the base, and a collimator mounted on the base, over the array of light-emitting-diode chips. The LED chips of the array are typically arranged in an inline manner. The collimator is generally configured as a rectangular, horn-like member and typically includes a first set of walls that collimate the light emitted by the LED chips in a first direction and a second set of walls that minimally collimate the light emitted by the LED chips in a second direction.
    Type: Application
    Filed: October 22, 2001
    Publication date: April 24, 2003
    Inventors: Thomas M. Marshall, Frank Jeroen Pieter Schuurmans, Douglas Peter Woolverton, Michael David Pashley
  • Publication number: 20030072147
    Abstract: A storage compartment is equipped with a light emitting diode (LED) light source for illuminating contents inside the compartment. The LED light source includes a LED light engine outside the compartment and a light guide inside the compartment. The light guide is optically coupled to be LED light engine to bring light from the LED light engine into the compartment for providing illumination inside the compartment. The LED light engine may include red, green, and blue LEDs that contribute to the illumination inside the compartment. Respective outputs of the red, green, and blue LEDs may be separately controllable to allow a variably controlled color point of illumination inside the compartment. Total output of the LED light engine may be controllable to vary intensity of illumination inside the compartment.
    Type: Application
    Filed: October 12, 2001
    Publication date: April 17, 2003
    Inventors: Michael D. Pashley, Thomas M. Marshall, Ans Saalsberg, Larry McColloch
  • Publication number: 20030067773
    Abstract: A hybrid lighting system for producing white light including at least one light emitting diode and phosphor-light emitting diode. The hybrid lighting system exhibits improved performance over conventional LED lighting systems that use LEDs or phosphor-LEDs to produce white light. In particular, the hybrid system of the invention permits different lighting system performance parameters to be addressed and optimized as deemed important, by varying the color and number of the LEDs and/or the phosphor of the phosphor LED.
    Type: Application
    Filed: November 22, 2002
    Publication date: April 10, 2003
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman
  • Publication number: 20030030808
    Abstract: White light emitting LED luminaire incorporates an array of red, green and blue emitting LEDs and a feedback arrangement to maintain a desired color balance. The feedback arrangement includes photodiodes positioned and enabled to separately measure the light output of each RGB color component. In one embodiment, a single photodiode or array of photodiodes is positioned to intercept reflected light from a partially reflecting element placed in the path of the combined output of the LED array. Individual colors are measured sequentially by pulsing the LEDs and photodiodes or by the use of color filters. In an alternate embodiment, each LED has an associated photodiode, either incorporated into the LED package or in a separate package.
    Type: Application
    Filed: June 7, 2001
    Publication date: February 13, 2003
    Inventors: Thomas M. Marshall, Michael D. Pashley, Frank J.P. Schuurmans
  • Patent number: 6513949
    Abstract: A hybrid lighting system for producing white light including at least one light emitting diode and phosphor-light emitting diode. The hybrid lighting system exhibits improved performance over conventional LED lighting systems that use LEDs or phosphor-LEDs to produce white light. In particular, the hybrid system of the invention permits different lighting system performance parameters to be addressed and optimized as deemed important, by varying the color and number of the LEDs and/or the phosphor of the phosphor LED.
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: February 4, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman
  • Patent number: 6445139
    Abstract: A luminaire comprises an array of LEDs that include at least one LED in each of a plurality of colors. Supplied to the LEDs for each color is an electrical current that, during a measuring period, comprises a measuring drive pulse having at least a first boost portion and a turn-off portion. The LEDs relating to each color have a light output which has a nominal continuous value during ordinary operation and increases during the boost portion and is interrupted during the turn-off portion. The array has a combined light output when current is supplied to all of the LEDs in the array. A photodiode is arranged to measure the combined light output which selectively turning off the electrical current to the LEDs so that the photodiode measures the light output for each color separately in response to the measuring drive pulse. The average light output during the measuring period is substantially equal to the nominal continuous light output during the ordinary operation so as to avoid visible flickers.
    Type: Grant
    Filed: September 15, 2000
    Date of Patent: September 3, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Thomas M. Marshall, Michael D. Pashley
  • Patent number: 6443594
    Abstract: A lens array for a lamp directs light to a light conduit such as an optical fiber or light pipe for guiding light to a remote location. An array of LED serve as light sources. The lens array includes an integrally formed member having a number of collimator lenses positioned in the lens array so that each lens can operate as a collimator for a corresponding LED to produce a respective collimated beam of light. The lenses have optical properties that are optimized according to where their corresponding LED are positioned in the LED array, so that the lens array is provided with lens prescriptions that produce refraction of the collimated beams of light toward an entrance aperture of the light conduit.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: September 3, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Thomas M. Marshall, Gerard Harbers, Michael D. Pashley, Stephen Herman
  • Publication number: 20020080623
    Abstract: According to this invention, a side-emitting illumination device for uniformly distributing light is composed of an LED light source, a light-transmitting rod which permits total internal reflection, and outcoupling material affixed to an outer surface of the rod. Light enters the rod at one end and travels along the rod by total internal reflection. Light that hits the outcoupling material is angularly distributed based on the width of the outcoupling material.
    Type: Application
    Filed: December 27, 2000
    Publication date: June 27, 2002
    Inventors: Michael D. Pashley, Thomas M. Marshall, Frank J.P. Schuurmans
  • Patent number: 6257737
    Abstract: A linear array of LED light sources in a plurality of colors is situated along the length of a reflector which is positioned so that it receives substantially all the light within the semi-cone angles of the sources, and is shaped so that it is illuminated substantially uniformly along its width. The reflector may be configured as a smooth Lambertian surface, or may be configured as a curve approximated by a series of flat specular reflecting segments.
    Type: Grant
    Filed: May 20, 1999
    Date of Patent: July 10, 2001
    Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman
  • Patent number: 6200002
    Abstract: A light source includes an array of LEDs in each of a plurality colors such as red, green, and blue in the entrance aperture of a tubular reflector which preferably has convex walls facing the optic axis and flares outward toward the exit aperture, and preferably has a polygonal cross section such as a square. Mixing of colors is further promoted by utilizing a large number of small LEDs with the LEDs of each color being centered on the optic axis.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: March 13, 2001
    Assignee: Philips Electronics North America Corp.
    Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman, Jeffrey A. Shimizu
  • Patent number: 6153980
    Abstract: A device, e.g., a luminaire, that includes a plurality of LEDs connected in series, and an active shunt arrangement for sensing a failure of one or more of the LEDs and for shunting current that would have otherwise flowed through a failed LED, to thereby maintain a flow of current through remaining ones of the plurality of LEDs. In one exemplary embodiment, the active shunt arrangement includes a plurality of active shunts connected in parallel across respective ones of the LEDs, and remote sense and digital control logic for detecting an open-circuit condition of the normally closed circuit, and for sequentially activating the active shunts until the normally closed circuit has been restored to a closed-circuit condition.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: November 28, 2000
    Assignee: Philips Electronics North America Corporation
    Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman, Gert W. Bruning
  • Patent number: 6139166
    Abstract: Apparatus for mixing light from discrete LED light sources utilizes beam splitters which each have a semi-reflective layer which partially transmits and partially reflects light of any wavelength incident thereon. Each semi-reflective layer is situated in a transparent prismatic black between reflective surfaces on parallel outside faces of the block so that two parallel input beams are mixed and transmitted as two parallel mixed beams of like color. For a square array of light sources, a first mixing stage consists of two such prismatic blocks arranged side-by-side, and a second mixing stage consists of two such prismatic blocks arranged side-by-side and rotated 90 degrees to the first stage. The second stage is arranged to receive a square array of mixed beams and produces four identical output beams. The colors of the light sources are chosen so that all output beams are white.
    Type: Grant
    Filed: June 24, 1999
    Date of Patent: October 31, 2000
    Assignees: LumiLeds Lighting B.V., Philips Electronics North America Corp.
    Inventors: Thomas M. Marshall, Michael D. Pashley, Matthijs H. Keuper
  • Patent number: 6127783
    Abstract: A white light emitting luminaire includes a plurality of LEDs in each of the colors red, green, and blue with a separate power supply for each color and a photodiode arranged to measure the light output of all the LEDs. The light output of each color is measured by an electronic control circuit which turns off the LEDs for the colors not being measured in a sequence of time pulses. The measured light output for each color is compared to a desired output, which may be determined by user inputs, and corrections to the current for each color are made accordingly.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: October 3, 2000
    Assignee: Philips Electronics North America Corp.
    Inventors: Michael D. Pashley, Thomas M. Marshall
  • Patent number: 5363395
    Abstract: A blue-green II/VI semiconductor injection laser utilizing a Zn.sub.1-u Cd.sub.u Se active layer (quantum well) having Zn.sub.1-x Mg.sub.x S.sub.y Se.sub.1-y cladding layers and ZnS.sub.z Se.sub.1-z guiding layers on a GaAs substrate. These devices are operable in a pulse mode at room temperature.
    Type: Grant
    Filed: November 30, 1993
    Date of Patent: November 8, 1994
    Assignee: North American Philips Corporation
    Inventors: James M. Gaines, Ronald R. Drenten, Kevin W. Haberern, Thomas M. Marshall, Piotr M. Mensz, John Petruzzello