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).
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Patent number: 6783269Abstract: 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: GrantFiled: December 27, 2000Date of Patent: August 31, 2004Assignee: Koninklijke Philips Electronics N.V.Inventors: Michael D. Pashley, Thomas M. Marshall, Frank J. P. Schuurmans
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Patent number: 6741351Abstract: 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: GrantFiled: June 7, 2001Date of Patent: May 25, 2004Assignee: Koninklijke Philips Electronics N.V.Inventors: Thomas M Marshall, Michael D Pashley, Frank J P Schuurmans
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Patent number: 6726341Abstract: 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: GrantFiled: October 12, 2001Date of Patent: April 27, 2004Assignee: Koninklijke Philips Electronics N.V.Inventors: Michael D. Pashley, Thomas M. Marshall, Ans Saalberg, Larry McColloch
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Patent number: 6692136Abstract: 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: GrantFiled: November 22, 2002Date of Patent: February 17, 2004Assignee: Koninklijke Philips Electronics N.V.Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman
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Publication number: 20030076034Abstract: 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: ApplicationFiled: October 22, 2001Publication date: April 24, 2003Inventors: Thomas M. Marshall, Frank Jeroen Pieter Schuurmans, Douglas Peter Woolverton, Michael David Pashley
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Publication number: 20030072147Abstract: 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: ApplicationFiled: October 12, 2001Publication date: April 17, 2003Inventors: Michael D. Pashley, Thomas M. Marshall, Ans Saalsberg, Larry McColloch
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Publication number: 20030067773Abstract: 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: ApplicationFiled: November 22, 2002Publication date: April 10, 2003Applicant: Koninklijke Philips Electronics N.V.Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman
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Publication number: 20030030808Abstract: 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: ApplicationFiled: June 7, 2001Publication date: February 13, 2003Inventors: Thomas M. Marshall, Michael D. Pashley, Frank J.P. Schuurmans
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Patent number: 6513949Abstract: 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: GrantFiled: December 2, 1999Date of Patent: February 4, 2003Assignee: Koninklijke Philips Electronics N.V.Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman
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Patent number: 6445139Abstract: 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: GrantFiled: September 15, 2000Date of Patent: September 3, 2002Assignee: Koninklijke Philips Electronics N.V.Inventors: Thomas M. Marshall, Michael D. Pashley
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Patent number: 6443594Abstract: 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: GrantFiled: March 31, 2000Date of Patent: September 3, 2002Assignee: Koninklijke Philips Electronics N.V.Inventors: Thomas M. Marshall, Gerard Harbers, Michael D. Pashley, Stephen Herman
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Publication number: 20020080623Abstract: 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: ApplicationFiled: December 27, 2000Publication date: June 27, 2002Inventors: Michael D. Pashley, Thomas M. Marshall, Frank J.P. Schuurmans
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Patent number: 6257737Abstract: 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: GrantFiled: May 20, 1999Date of Patent: July 10, 2001Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman
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Patent number: 6200002Abstract: 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: GrantFiled: March 26, 1999Date of Patent: March 13, 2001Assignee: Philips Electronics North America Corp.Inventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman, Jeffrey A. Shimizu
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Patent number: 6153980Abstract: 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: GrantFiled: November 4, 1999Date of Patent: November 28, 2000Assignee: Philips Electronics North America CorporationInventors: Thomas M. Marshall, Michael D. Pashley, Stephen Herman, Gert W. Bruning
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Patent number: 6139166Abstract: 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: GrantFiled: June 24, 1999Date of Patent: October 31, 2000Assignees: LumiLeds Lighting B.V., Philips Electronics North America Corp.Inventors: Thomas M. Marshall, Michael D. Pashley, Matthijs H. Keuper
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Patent number: 6127783Abstract: 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: GrantFiled: December 18, 1998Date of Patent: October 3, 2000Assignee: Philips Electronics North America Corp.Inventors: Michael D. Pashley, Thomas M. Marshall
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Patent number: 5363395Abstract: 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: GrantFiled: November 30, 1993Date of Patent: November 8, 1994Assignee: North American Philips CorporationInventors: James M. Gaines, Ronald R. Drenten, Kevin W. Haberern, Thomas M. Marshall, Piotr M. Mensz, John Petruzzello