Patents Assigned to PhotonStar LED Limited
  • Publication number: 20110101394
    Abstract: A light emitting module comprises a light emitting device (LED) mounted on a high thermal dissipation sub-mount, which performs the traditionally function of heat spread and the first part of the heat sinking. The sub-mount is a grown metal that is formed by an electroplating, electroforming, electrodeposition or electroless plating process, thereby minimising thermal resistance at this stage. An electrically insulating and thermally conducting layer is at least partially disposed across the interface between the grown semiconductor layers of the light emitting device and the formed metal layers of the sub-mount to further improve the electrical isolation of the light emitting device from the grown sub-mount. The top surface of the LED is protected from electroplating or electroforming by a wax or polymer or other removable material on a temporary substrate, mould or mandrel, which can be removed after plating, thereby releasing the LED module for subsequent processing.
    Type: Application
    Filed: November 10, 2008
    Publication date: May 5, 2011
    Applicant: PHOTONSTAR LED LIMITED
    Inventors: James Stuart McKenzie, Majd Zoorob
  • Publication number: 20110001157
    Abstract: A light emitting module with improved optical functionality and reduced thermal resistance is described, which comprises a light emitting device (LED), a wavelength converting (WC) element and an inorganic optically-transmissive thermally-conductive (OTTC) element. The WC element is capable of absorbing light generated from the LED at a specific wavelength and re-emitting light having a different wavelength. The re-emitted light and any unabsorbed light exits through at least one surface of the module. The OTTC is in physical contact with the WC element and at least partially located in the optical path of the light. The OTTC comprises one or more layers of inorganic material having a thermal conductivity greater than that of the WC element. As such, a compact unitary integrated module is provided with excellent thermal characteristics, which may be further enhanced when the OTTC provides a thermal barrier for vertical heat propagation through the module but not lateral propagation.
    Type: Application
    Filed: January 28, 2009
    Publication date: January 6, 2011
    Applicant: PHOTONSTAR LED LIMITED
    Inventors: James Stuart McKenzie, Majd Zoorob
  • Publication number: 20100283075
    Abstract: A light emitting device having a plurality of light extracting elements defined on an upper surface of a semiconductor layer of the device, wherein the light extracting elements are adapted to couple light out of the device and to modify the far field emission profile of the device. Each element comprises an elongate region having a length at least twice its width and also greater than the effective dominant wavelength of light generated in the device. The elongate region extends orthogonal to the upper surface but not into the light emitting region of the device and may be oriented at an angle of less than 45° relative to one of a pair of basis axis defining a plane parallel to the semiconductor layer. Each elongate region is spatially separated from neighbouring elongate regions such that it perturbs light generated in the light emitting region independently of the neighbouring regions.
    Type: Application
    Filed: November 10, 2008
    Publication date: November 11, 2010
    Applicant: PHOTONSTAR LED LIMITED
    Inventors: James Stuart McKenzie, Majd Zoorob
  • Publication number: 20100213485
    Abstract: A light emitting device comprises a novel low-loss array of conductive vias embedded in a dielectric multilayer stack, to act as an electrically-conductive, low-loss, high-reflectivity reflector layer (CVMR). In one example the CVMR stack is employed between a reflective metal bottom contact and a p-GaN semiconductor flip chip layer. The CVMR stack comprises at least (3) layers with at least (2) differing dielectric constants. The conductive vias are arranged such that localised and propagating surface plasmons associated with the structure reside within the electromagnetic stopband of the CVMR stack, which in turn inhibits trapped LED modes coupling into these plasmonic modes, thereby increasing the overall reflectivity of the CVM R. This technique improves optical light extraction and provides a vertical conduction path for optimal current spreading in a semiconductor light emitting device. A light emitting module and method of manufacture are also described.
    Type: Application
    Filed: July 18, 2008
    Publication date: August 26, 2010
    Applicant: PhotonStar LED Limited
    Inventors: James Stuart McKenzie, Majd Zoorob
  • Publication number: 20100201280
    Abstract: A light emitting device is provided having high luminous output while maintaining high wall plug efficiency, wherein the high thermal and electrical conductivity paths of the device are separated during the semiconductor wafer and die level manufacturing step. The device includes an electrical conducting mirror layer, which reflects at least 60% of generated light incident on it, and an isolation layer having electrical insulating properties and thermal conducting properties. A first electrode, which is not in contact with the main semiconductor layers of the device, is located on the mirror layer. A light emitting module, system and projection system incorporating the light emitting device are also described, as is a method of manufacture of the device.
    Type: Application
    Filed: September 12, 2008
    Publication date: August 12, 2010
    Applicant: PHOTONSTAR LED LIMITED
    Inventors: James Stuart McKenzie, Majd Zoorob
  • Publication number: 20100038669
    Abstract: A light emitting device (LED) employs one or more conductive multilayer reflector (CMR) structures. Each CMR is located between the light emitting region and a metal electrical contact region, thereby acting as low-loss, high-reflectivity region that masks the lossy metal contact regions away from the trapped waveguide modes. Improved optical light extraction via an upper surface is thereby achieved and a vertical conduction path is provided for current spreading in the device. In an example vertical, flip-chip type device, a CMR is employed between the metal bottom contact and the p-GaN flip chip layer. A complete light emitting module comprises the LED and encapsulant layers with a phosphor. Also provided is a method of manufacture of the LED and the module.
    Type: Application
    Filed: March 3, 2008
    Publication date: February 18, 2010
    Applicant: PHOTONSTAR LED LIMITED
    Inventor: James Stuart McKenzie