Patents Assigned to Lumileds Lighting U.S., LLC
  • Publication number: 20110134626
    Abstract: The invention provides an illumination system and a method for illumination. The illumination system includes one or more light sources that produce a primary light, a light-mixing zone that homogenizes the primary light, a wavelength-converting layer that converts the primary light to a secondary light, and a light-transmitting zone that receives the secondary light and transmits the secondary light to, for example, a Liquid Crystal Display (LCD).
    Type: Application
    Filed: February 15, 2011
    Publication date: June 9, 2011
    Applicant: LUMILEDS LIGHTING U.S., LLC
    Inventors: Mark PUGH, Gerard HARBERS
  • Patent number: 7692373
    Abstract: A light-emitting device comprising a population of quantum dots (QDs) embedded in a host matrix and a primary light source which causes the QDs to emit secondary light and a method of making such a device. The size distribution of the QDs is chosen to allow light of a particular color to be emitted therefrom. The light emitted from the device may be of either a pure (monochromatic) color, or a mixed (polychromatic) color, and may consist solely of light emitted from the QDs themselves, or of a mixture of light emitted from the QDs and light emitted from the primary source. The QDs desirably are composed of an undoped semiconductor such as CdSe, and may optionally be overcoated to increase photoluminescence.
    Type: Grant
    Filed: April 13, 2007
    Date of Patent: April 6, 2010
    Assignees: Massachusetts Institute of Technology, Lumileds Lighting U.S., LLC
    Inventors: Moungi E. Bawendi, Jason Heine, Klavs F. Jensen, Jeffrey N. Miller, Ronald L. Moon
  • Patent number: 7535168
    Abstract: A light-emitting diode comprises a chip emitting visible light of a first wavelength, a light-emitting surface and a phosphor layer provided on the light-emitting surface. Said phosphor layer is capable of converting light of the first wavelength to visible light of a second wavelength. According to the invention, a part of the light-emitting surface is not covered with the phosphor layer. Preferably, the size of said surface is chosen to be such that by mixing emitted light of the first and the second wavelength substantially white light is obtained. Preferably, the surface that is not covered with the phosphor layer comprises a plurality of sub-surfaces, preferably arranged in the form of a pattern.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: May 19, 2009
    Assignee: Philips Lumiled Lighting, U.S. LLC
    Inventor: Matthijs Hendrik Keuper
  • Patent number: 7514721
    Abstract: A semiconductor structure including a light emitting layer disposed between an n-type region and a p-type region is attached to a compound substrate including a host which provides mechanical support to the device and a ceramic layer including a luminescent material. In some embodiments the compound substrate includes a crystalline seed layer on which the semiconductor structure is grown. The ceramic layer is disposed between the seed layer and the host. In some embodiments, the compound substrate is attached to the semiconductor structure compound substrate is spaced apart from the semiconductor structure and does not provide mechanical support to the structure. In some embodiments, the ceramic layer has a thickness less than 500 ?m.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: April 7, 2009
    Assignees: Koninklijke Philips Electronics N.V., Philips Lumiled Lighting, U.S. LLC
    Inventors: Michael R. Krames, Peter J. Schmidt
  • Publication number: 20080224158
    Abstract: A light emitting device having a stack of layers bonded to an undoped substrate with a doped layer between the stack of layers and the undoped substrate. The stack of layers include a layer of first conductivity type over the doped layer, an overlying light emitting layer and a layer of second conductivity type. In one embodiment, the doped substrate is grown on a sacrificial substrate along with the remaining stack of layers prior to bonding to the undoped substrate. Electrical contacts are coupled to device on a side opposite the undoped substrate. In one embodiment, the layers of first conductivity, the light emitting layer, and the layer of second conductivity are removed to expose the doped layer and a first electrical contact is coupled to the layer of first conductivity through the doped substrate, while a second electrical contact is coupled to the layer of second conductivity.
    Type: Application
    Filed: September 24, 2007
    Publication date: September 18, 2008
    Applicant: LUMILEDS LIGHTING U.S., LLC
    Inventor: Decai Sun
  • Publication number: 20080186702
    Abstract: A device is provided with an array of a plurality of phosphor converted light emitting devices (LEDs) that produce broad spectrum light. The phosphor converted LEDs may produce light with different correlated color temperature (CCT) and are covered with an optical element that assists in mixing the light from the LEDs to produce a desired correlated color temperature. The phosphor converted LEDs may also be combined in an array with color LEDs. The color LEDs may be controlled to vary their brightness such that light with an approximately continuous broad spectrum is produced. By controlling the brightness of the color LEDs, light can be produced with a fixed brightness over a large range of white points with a high color rendering quality.
    Type: Application
    Filed: April 7, 2008
    Publication date: August 7, 2008
    Applicant: Lumileds Lighting U.S., LLC
    Inventors: Michael D. Camras, William R. Imler, Franklin J. Wall, Frank M. Steranka, Michael R. Krames, Helena Ticha, Ladislav Tichy, Robertus G. Alferink
  • Patent number: 7264527
    Abstract: A light-emitting device comprising a population of quantum dots (QDs) embedded in a host matrix and a primary light source which causes the QDs to emit secondary light and a method of making such a device. The size distribution of the QDs is chosen to allow light of a particular color to be emitted therefrom. The light emitted from the device may be of either a pure (monochromatic) color, or a mixed (polychromatic) color, and may consist solely of light emitted from the QDs themselves, or of a mixture of light emitted from the QDs and light emitted from the primary source. The QDs desirably are composed of an undoped semiconductor such as CdSe, and may optionally be overcoated to increase photoluminescence.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: September 4, 2007
    Assignee: Lumileds Lighting U.S., LLC
    Inventors: Moungi E. Bawendi, Jason Heine, Klavs F. Jensen, Jeffrey N. Miller, Ronald L. Moon
  • Publication number: 20070138494
    Abstract: The invention provides a light-emitting device and a method of illumination. The light-emitting device includes one or more semiconductor layers, a reflective bottom surface, and a top surface coupled to semiconductor layer. The semiconductor layers include an active region where a primary light is generated. The relative position of the top surface, the reflective bottom surface and the active region is adjusted to substantially transmit the primary light through the sides of the light-emitting device.
    Type: Application
    Filed: December 19, 2005
    Publication date: June 21, 2007
    Applicant: LUMILEDS LIGHTING U.S., LLC
    Inventors: Mark Pugh, Gerard Harbers, Robert West
  • Publication number: 20070097696
    Abstract: Collection optics are used with one or more light emitting diodes to produce, e.g., collimated light. The collection optics are produced in multiple pieces including a small reflective ring that surrounds the one or more light emitting diodes. The reflective ring may be positioned relative to the LEDs, using a mesa upon which the LEDs are mounted, as a lateral positioning guide. A separate upper reflector uses the reflective ring as a lateral positioning guide during assembly. The reflective ring and the upper reflector include reflective sidewalls that are approximately continuous when the reflective ring and upper reflector are assembled.
    Type: Application
    Filed: October 28, 2005
    Publication date: May 3, 2007
    Applicant: Lumileds Lighting U.S., LLC
    Inventors: Gregory Eng, Mina Farr, Matthijs Keuper, Stefan Eberle, Franklin Wall
  • Publication number: 20070091602
    Abstract: A plurality of light emitting diode dies (LED) with associated secondary optics, which produce different light distribution patterns, are combined to produce an efficient light source having a desired illumination pattern. By way of example, a first LED may include a lens that produces a light distribution pattern with a maximum intensity at the center while a second LED may use a lens that produces a light distribution pattern with a maximum intensity that surrounds the maximum intensity of the pattern produced by the first LED. The light from the LEDs can then be combined to produce a desired illumination pattern. Additional LEDs and lenses, e.g., having different light distribution patterns may be used if desired. Moreover, a variable current driver may be used to vary the amount of current to the different LEDs, such that the combined illumination pattern may be varied as desired.
    Type: Application
    Filed: October 25, 2005
    Publication date: April 26, 2007
    Applicant: Lumileds Lighting U.S., LLC
    Inventors: Pieter van Voorst Vader, Pascal Bloemen, Nicola Pfeffer
  • Publication number: 20070086184
    Abstract: The invention provides an illumination system and a method for illumination. The illumination system includes one or more light sources that produce a primary light, a light-mixing zone that homogenizes the primary light, a wavelength-converting layer that converts the primary light to a secondary light, and a light-transmitting zone that receives the secondary light and transmits the secondary light to, for example, a Liquid Crystal Display (LCD).
    Type: Application
    Filed: October 17, 2005
    Publication date: April 19, 2007
    Applicant: LUMILEDS LIGHTING U.S., LLC
    Inventors: Mark Pugh, Gerard Harbers
  • Publication number: 20070076412
    Abstract: A light system includes a plurality of light emitting elements, such as light emitting diodes, arranged in an array. One or more light emitting elements are positioned in a center region of the array. The light emitting elements in the center region have superior performance, such as luminance and/or efficiency, relative to the remainder of the light emitting elements in the array. A second region that is outside the center region, i.e., farther from the center of the array, include a second group of light emitting elements that have superior performance relative to any additional light emitting elements in the array. The array may include additional regions farther from the center of the array that include light emitting elements with lower performance. A collection optic having an optical axis is optically coupled to the array such that the optical axis is located at approximately the center of the array.
    Type: Application
    Filed: September 30, 2005
    Publication date: April 5, 2007
    Applicant: Lumileds Lighting U.S., LLC
    Inventors: Gerald Harbers, Serge Bierhuizen
  • Publication number: 20070035852
    Abstract: An imaging system includes a wavelength dependent aperture stop, which transmits light with different ranges of wavelengths through apertures of different diameters. Thus, different colored light will have different F-stops, which can be selected based on the power transfer and image quality requirements for the different colored light. For example, a smaller F-stop may be used with a weaker light source to produce a higher throughput for a specific range of wavelengths. Accordingly, the optical system's design and optimization is wavelength and F-stop dependent.
    Type: Application
    Filed: August 12, 2005
    Publication date: February 15, 2007
    Applicant: Lumileds Lighting U.S., LLC
    Inventor: Mina Farr
  • Publication number: 20070034890
    Abstract: A light emitting device includes a number of light emitting diode dies (LEDs) mounted on a shared submount and covered with a single lens element that includes a corresponding number of lens elements. The LEDs are separated from each other by a distance that is sufficient for lens element to include separate lens elements for each LED. The separation of the LEDs and lens elements may be configured to produce a desired amount of light on a target at a predefined distance. In one embodiment, the lens elements are approximately flat type lens elements, such as Fresnel, TIR, diffractive lens, photonic crystal type lenses, prism, or reflective lens.
    Type: Application
    Filed: August 10, 2005
    Publication date: February 15, 2007
    Applicant: Lumileds Lighting U.S., LLC
    Inventors: Walter Daschner, Xina Quan, Nanze Wang
  • Patent number: 7071494
    Abstract: A light emitting device includes a substrate, a textured layer overlying the substrate, at least one III-nitride layer overlying the textured layer, and a substantially planar light emitting region. Devices incorporating scattering layers may be formed by several different methods. In a first method, an epitaxial layer is deposited then etched to form the textured layer. In a second method, a photomask is deposited and patterned to create openings in the photomask. The textured layer is then preferentially deposited in the openings formed in the photomask. In a third method, the textured layer is deposited under conditions that favor three-dimensional growth, then optionally annealed.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: July 4, 2006
    Assignee: Lumileds Lighting U.S. LLC
    Inventors: Daniel A. Steigerwald, Jerome C. Bhat
  • Patent number: 7064355
    Abstract: Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent optical element having a refractive index for light emitted by the active region preferably greater than about 1.5, more preferably greater than about 1.8. A method of bonding a transparent optical element (e.g., a lens or an optical concentrator) to a light emitting device comprising an active region includes elevating a temperature of the optical element and the stack and applying a pressure to press the optical element and the light emitting device together. A block of optical element material may be bonded to the light emitting device and then shaped into an optical element. Bonding a high refractive index optical element to a light emitting device improves the light extraction efficiency of the light emitting device by reducing loss due to total internal reflection.
    Type: Grant
    Filed: June 12, 2001
    Date of Patent: June 20, 2006
    Assignee: Lumileds Lighting U.S., LLC
    Inventors: Michael D. Camras, Michael R. Krames, Wayne L. Snyder, Frank M. Steranka, Robert C. Taber, John J. Uebbing, Douglas W. Pocius, Troy A. Trottier, Christopher H. Lowery, Gerd O. Mueller, Regina B. Mueller-Mach, Gloria E. Hofler
  • Patent number: 7053419
    Abstract: Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent lens having a refractive index for light emitted by the active region preferably greater than about 1.5, more preferably greater than about 1.8. A method of bonding a transparent lens to a light emitting device having a stack of layers including semiconductor layers comprising an active region includes elevating a temperature of the lens and the stack and applying a pressure to press the lens and the stack together. Bonding a high refractive index lens to a light emitting device improves the light extraction efficiency of the light emitting device by reducing loss due to total internal reflection. Advantageously, this improvement can be achieved without the use of an encapsulant.
    Type: Grant
    Filed: September 12, 2000
    Date of Patent: May 30, 2006
    Assignee: LumiLeds Lighting U.S., LLC
    Inventors: Michael D. Camras, Michael R. Krames, Wayne L. Snyder, Frank M. Steranka, Robert C. Taber, John J. Uebbing, Douglas W. Pocius, Troy A. Trottier, Christopher H. Lowery, Gerd O. Mueller, Regina B. Mueller-Mach
  • Patent number: 7049159
    Abstract: A method for forming a luminescent layer on a light emitting semiconductor device includes positioning a stencil on a substrate such that a light emitting semiconductor device disposed on the substrate is located within an opening in the stencil, depositing a stenciling composition including luminescent material in the opening, removing the stencil from the substrate, and curing the stenciling composition to a solid state. The resulting light emitting device includes a stack of layers including semiconductor layers comprising an active region and a luminescent material containing layer having a substantially uniform thickness disposed around at least a portion of the stack. A surface of the luminescent material containing layer not adjacent to the stack substantially conforms to a shape of the stack. In one embodiment, the light emitting device emits white light in a uniformly white spatial profile.
    Type: Grant
    Filed: November 5, 2003
    Date of Patent: May 23, 2006
    Assignee: Lumileds Lighting U.S., LLC
    Inventor: Christopher H. Lowery
  • Patent number: 7048412
    Abstract: A lamp has LED sources that are placed about a lamp axis in an axial arrangement. The lamp includes a post with post facets where the LED sources are mounted. The lamp includes a segmented reflector for guiding light from the LED sources. The segmented reflector includes reflective segments each of which is illuminated primarily by light from one of the post facets (e.g., one of the LED sources on the post facet). The LED sources may be made up of one or more LED dies. The LED dies may include optic-on-chip lenses to direct the light from each post facet to a corresponding reflective segment. The LED dies may be of different sizes and colors chosen to generate a particular far-field pattern.
    Type: Grant
    Filed: June 10, 2002
    Date of Patent: May 23, 2006
    Assignee: Lumileds Lighting U.S., LLC
    Inventors: Paul S. Martin, R. Scott West, Daniel A. Steigerwald
  • Publication number: 20060105478
    Abstract: A device is provided with at least one light emitting device (LED) die mounted on a submount with an optical element subsequently thermally bonded to the LED die. The LED die is electrically coupled to the submount through contact bumps that have a higher temperature melting point than is used to thermally bond the optical element to the LED die. In one implementation, a single optical element is bonded to a plurality of LED dice that are mounted to the submount and the submount and the optical element have approximately the same coefficients of thermal expansion. Alternatively, a number of optical elements may be used. The optical element or LED die may be covered with a coating of wavelength converting material. In one implementation, the device is tested to determine the wavelengths produced and additional layers of the wavelength converting material are added until the desired wavelengths are produced.
    Type: Application
    Filed: November 12, 2004
    Publication date: May 18, 2006
    Applicant: Lumileds Lighting U.S., LLC
    Inventors: Michael Camras, William Imler, Franklin Wall, Frank Steranka, Michael Krames, Helena Ticha, Ladislav Tichy