Patents by Inventor David Hum
David Hum 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: 8395312Abstract: A light source having first and second LEDs and a phosphor layer that converts light generated by the first LED is disclosed. The first LED emits light at a first wavelength. The layer of phosphor is illuminated by the first LED, the phosphor being excited by light of the first wavelength to convert light of the first wavelength to a band of wavelengths having wavelengths between the first wavelength and a second wavelength. The second LED emits light at a third wavelength that is greater than the first wavelength. The phosphor is not substantially excited by light of the third wavelength. The combined light from the phosphor, and first and second LEDs is perceived as being white by a human observer.Type: GrantFiled: April 19, 2010Date of Patent: March 12, 2013Assignee: Bridgelux, Inc.Inventor: David Hum
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Patent number: 8330390Abstract: A lighting apparatus and method for operating LED-based lighting devices are disclosed. The apparatus includes a receiver that receives a potential from a power source whose output varies as a function of time, an energy storage device, and an LED array. The energy storage device stores energy from the power source when the driving potential is greater than a predetermined value. The LED array has variable forward bias potential, the LED array generating light when a potential across the array is greater than the selected forward bias potential. A source selector connects the energy storage device to the array when the potential from the power source is less than a predetermined value. A controller that varies the forward bias potential such that the difference between the forward bias potential and potential across the array is maintained at a value less than a predetermined value.Type: GrantFiled: April 11, 2011Date of Patent: December 11, 2012Assignee: Bridgelux, Inc.Inventors: David Hum, Steven D. Lester
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Patent number: 8247998Abstract: A light-emitting device capable of being powered by an AC power supply or an unregulated DC power supply is disclosed. The light-emitting device, in an aspect, is coupled to a controller, a light-emitting diode (“LED”) array, and a power supply, wherein the power supply can be an AC power source or an unregulated DC power source. While the power supply provides electrical power, the controller generates various LED control signals in response to power fluctuation of the electrical power. The LED array allows at least a portion of LEDs to be activated in accordance with the logic states of the LED control signals.Type: GrantFiled: March 23, 2011Date of Patent: August 21, 2012Assignee: Bridgelux, Inc.Inventors: David Hum, Steve Lester
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Patent number: 8227828Abstract: A light source includes a substrate, a light emitting diode on the substrate, and a phosphor layer over the light emitting diode. A plate is on the phosphor layer. An attachment member is coupled to the plate and is configured to conduct heat away from the plate.Type: GrantFiled: December 1, 2010Date of Patent: July 24, 2012Assignee: Bridgelux, Inc.Inventors: Jianhua Li, Rene Helbing, David Hum
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Patent number: 8222652Abstract: A method for controlling color accuracy of a light-emitting semiconductor-based device, and a process for producing a light-emitting semiconductor-based device with desired color accuracy is disclosed. The color accuracy is controlled by defining a desired color accuracy of a light produced by mixing colors emitted by at least two light sources over a first range of operating conditions; determining characteristics of the light as a function of operating conditions; and establishing desired light characteristics of the at least two light sources over a second range of operating condition in accordance with the step of defining and the step of determining.Type: GrantFiled: April 20, 2010Date of Patent: July 17, 2012Assignee: Bridgelux, Inc.Inventors: Shane Harrah, David Hum
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Publication number: 20120133289Abstract: A lighting apparatus and method for operating LED-based lighting devices are disclosed. The apparatus includes a receiver that receives a potential from a power source whose output varies as a function of time, an energy storage device, and an LED array. The energy storage device stores energy from the power source when the driving potential is greater than a predetermined value. The LED array has variable forward bias potential, the LED array generating light when a potential across the array is greater than the selected forward bias potential. A source selector connects the energy storage device to the array when the potential from the power source is less than a predetermined value. A controller that varies the forward bias potential such that the difference between the forward bias potential and potential across the array is maintained at a value less than a predetermined value.Type: ApplicationFiled: April 11, 2011Publication date: May 31, 2012Inventors: David Hum, Steven D. Lester
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Patent number: 8159153Abstract: A compound light source that compensates for changes in electrical conversion efficiency with increasing operating temperature is disclosed. The compound light source generates light of a design intensity at a design temperature in response to a drive current flowing through the light source. The light source includes a primary light source and a compensating light source. The primary and compensating light sources convert an electrical current passing therethrough to light, each light source being characterized by an electrical conversion efficiency that decreases with increasing temperature and that also decreases with increasing current. The compound light source includes a temperature sensor that measures the temperature of the primary light source and a current splitting circuit that divides the drive current between the primary and compensating light sources to compensate for the decrease in efficiency of the primary light source with temperature above the design temperature.Type: GrantFiled: October 1, 2010Date of Patent: April 17, 2012Assignee: Bridgelux, Inc.Inventor: David Hum
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Patent number: 8147093Abstract: A compound light source is characterized by an output spectral measure that lies within a spectral measure design range and an average light intensity per component light source that lies within an output intensity design range. The plurality of component light sources includes light sources whose spectral measure value and output intensity lie outside the corresponding design ranges. The component light sources are chosen from a number of predetermined groups obtained by sorting the component light sources with respect to the spectral measure value and output intensity of each source such that the compound light source has a spectral measure value and output intensity that lies within the corresponding design ranges.Type: GrantFiled: June 14, 2010Date of Patent: April 3, 2012Assignee: BridgeluxInventor: David Hum
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Publication number: 20120012865Abstract: A light source includes a substrate, a light emitting diode on the substrate, and a plate supporting member attached to the substrate and surrounding the light emitting diode to form a cavity. In addition, the light source includes a plate on the plate supporting member such that a distance between the plate and the substrate is approximately less than or equal to 1 mm. Furthermore, the light source includes a phosphor layer on the plate opposite the cavity.Type: ApplicationFiled: July 19, 2010Publication date: January 19, 2012Inventors: Jianhua Li, Rene Helbing, David Hum
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Patent number: 8089217Abstract: A light-emitting device capable of being powered by an AC power supply or an unregulated DC power supply is disclosed. The light-emitting device, in an aspect, is coupled to a controller, a light-emitting diode (“LED”) array, and a power supply, wherein the power supply can be an AC power source or an unregulated DC power source. While the power supply provides electrical power, the controller generates various LED control signals in response to power fluctuation of the electrical power. The LED array allows at least a portion of LEDs to be activated in accordance with the logic states of the LED control signals.Type: GrantFiled: April 5, 2011Date of Patent: January 3, 2012Assignee: Bridgelux, Inc.Inventors: David Hum, Steve Lester
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Publication number: 20110254027Abstract: A method for controlling color accuracy of a light-emitting semiconductor-based device, and a process for producing a light-emitting semiconductor-based device with desired color accuracy is disclosed. The color accuracy is controlled by defining a desired color accuracy of a light produced by mixing colors emitted by at least two light sources over a first range of operating conditions; determining characteristics of the light as a function of operating conditions; and establishing desired light characteristics of the at least two light sources over a second range of operating condition in accordance with the step of defining and the step of determining.Type: ApplicationFiled: April 20, 2010Publication date: October 20, 2011Inventors: Shane Harrah, David Hum
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Publication number: 20110181194Abstract: A light-emitting device capable of being powered by an AC power supply or an unregulated DC power supply is disclosed. The light-emitting device, in an aspect, is coupled to a controller, a light-emitting diode (“LED”) array, and a power supply, wherein the power supply can be an AC power source or an unregulated DC power source. While the power supply provides electrical power, the controller generates various LED control signals in response to power fluctuation of the electrical power. The LED array allows at least a portion of LEDs to be activated in accordance with the logic states of the LED control signals.Type: ApplicationFiled: April 5, 2011Publication date: July 28, 2011Applicant: BRIDGELUX, INC.Inventors: David Hum, Steve Lester
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Publication number: 20110169417Abstract: A light-emitting device capable of being powered by an AC power supply or an unregulated DC power supply is disclosed. The light-emitting device, in an aspect, is coupled to a controller, a light-emitting diode (“LED”) array, and a power supply, wherein the power supply can be an AC power source or an unregulated DC power source. While the power supply provides electrical power, the controller generates various LED control signals in response to power fluctuation of the electrical power. The LED array allows at least a portion of LEDs to be activated in accordance with the logic states of the LED control signals.Type: ApplicationFiled: March 23, 2011Publication date: July 14, 2011Applicant: Bridgelux, Inc.Inventors: David Hum, Steve Lester
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Patent number: 7936135Abstract: A light-emitting device capable of being powered by an AC power supply or an unregulated DC power supply is disclosed. The light-emitting device, in an aspect, is coupled to a controller, a light-emitting diode (“LED”) array, and a power supply, wherein the power supply can be an AC power source or an unregulated DC power source. While the power supply provides electrical power, the controller generates various LED control signals in response to power fluctuation of the electrical power. The LED array allows at least a portion of LEDs to be activated in accordance with the logic states of the LED control signals.Type: GrantFiled: July 17, 2009Date of Patent: May 3, 2011Assignee: Bridgelux, IncInventors: David Hum, Steve Lester
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Publication number: 20110073878Abstract: A light source includes a substrate, a light emitting diode on the substrate, and a phosphor layer over the light emitting diode. A plate is on the phosphor layer. An attachment member is coupled to the plate and is configured to conduct heat away from the plate.Type: ApplicationFiled: December 1, 2010Publication date: March 31, 2011Inventors: Jianhua Li, Rene Helbing, David Hum
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Publication number: 20110068715Abstract: A compound light source that compensates for changes in electrical conversion efficiency with increasing operating temperature is disclosed. The compound light source generates light of a design intensity at a design temperature in response to a drive current flowing through the light source. The light source includes a primary light source and a compensating light source. The primary and compensating light sources convert an electrical current passing therethrough to light, each light source being characterized by an electrical conversion efficiency that decreases with increasing temperature and that also decreases with increasing current. The compound light source includes a temperature sensor that measures the temperature of the primary light source and a current splitting circuit that divides the drive current between the primary and compensating light sources to compensate for the decrease in efficiency of the primary light source with temperature above the design temperature.Type: ApplicationFiled: October 1, 2010Publication date: March 24, 2011Inventor: David Hum
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Publication number: 20110069502Abstract: A mounting fixture for a light-emitting device such as an LED is disclosed. The fixture includes a base having a cavity adapted to receive a module having a light-emitting device mounted thereon, a cover, power contacts that provide electrical connections to the light-emitting device, a spring and a closure. The base has a heat-conducting surface. The cover has a window positioned to allow light from the light-emitting device to pass through the window. The first and second power contacts have first and second portions, respectively, adapted to receive external power connections on an outer surface of the mounting fixture. The spring forces the module against the heat-conducting surface when the base is in a closed position relative to the cover, the module being manually removable from the base when the cover is in an open position relative to the base. The closure reversibly attaches the base to the cover.Type: ApplicationFiled: April 14, 2010Publication date: March 24, 2011Inventor: David Hum
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Publication number: 20110068697Abstract: A light source having first and second LEDs and a phosphor layer that converts light generated by the first LED is disclosed. The first LED emits light at a first wavelength. The layer of phosphor is illuminated by the first LED, the phosphor being excited by light of the first wavelength to convert light of the first wavelength to a band of wavelengths having wavelengths between the first wavelength and a second wavelength. The second LED emits light at a third wavelength that is greater than the first wavelength. The phosphor is not substantially excited by light of the third wavelength. The combined light from the phosphor, and first and second LEDs is perceived as being white by a human observer.Type: ApplicationFiled: April 19, 2010Publication date: March 24, 2011Inventor: David Hum
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Publication number: 20110069482Abstract: A compound light source and method for making the same are disclosed. The compound light source is constructed from a plurality of component light sources and a method for constructing the same. The compound light source is characterized by an output spectral measure that lies within a spectral measure design range and an average light intensity per component light source that lies within an output intensity design range. The plurality of component light sources includes light source whose spectral measure and output intensity lie outside the ranges. The component light sources are chosen from a number of predetermined groups obtained by sorting the component light sources with respect to the spectral measure and output intensity of each source such that compound light source has a spectral measure and output intensity that lies within the corresponding design ranges.Type: ApplicationFiled: June 14, 2010Publication date: March 24, 2011Inventor: David Hum
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Patent number: 7855394Abstract: A light source includes a substrate, a light emitting diode on the substrate, and a phosphor layer over the light emitting diode. A plate is on the phosphor layer. An attachment member is coupled to the plate and is configured to conduct heat away from the plate.Type: GrantFiled: June 18, 2009Date of Patent: December 21, 2010Assignee: Bridgelux, Inc.Inventors: Jianhua Li, Rene Helbing, David Hum