Patents Assigned to Leotek Electronics Corporation
  • Patent number: 7347706
    Abstract: An LED lamp module for use with a threaded electrical socket connector is provided, which includes an LED light engine with a first electrical connector, a second electrical connector having a first end electrically engagable with the first electrical connector and a second end having a threaded outer surface compatible with a threaded electrical socket connector. The LED lamp module further comprises a sleeve surrounding the first electrical connector and the first end such that the sleeve allows for relative rotation between the first electrical connector and the first end in a loosened state, and restricts relative rotation between the first electrical connector and the first end in a tightened state. A method for installing a retrofit LED lamp module in a housing which physically restricts full rotation of an LED light engine is also provided.
    Type: Grant
    Filed: July 12, 2006
    Date of Patent: March 25, 2008
    Assignee: Leotek Electronics Corporation
    Inventors: Chen-Ho Wu, Chin-Wang Tu, Shih Chang Wang
  • Patent number: 7303309
    Abstract: A backlit sign with an LED module, with a housing that includes a top wall having a first length, a bottom wall having a second length, and a pair of opposing sidewalls each having a third length, wherein at least a portion of one of the sidewalls is translucent. One or more LED modules are mounted to the top wall and include a plurality of LEDs for producing light. The first, second and third lengths are selected to maximize illumination of the sidewalls by the produced light, and to minimize a width and weight of the sign. A mirror can be used to increase the reflectivity of the bottom wall.
    Type: Grant
    Filed: July 6, 2004
    Date of Patent: December 4, 2007
    Assignee: Leotek Electronics Corporation
    Inventors: Chen H. Wu, Steve Bacilieri
  • Patent number: 7172324
    Abstract: An illuminated sign having front, back and side surfaces. A plurality of first cavities are formed into the back surface of the sign. A plurality of light emitting modules are disposed in the plurality of first cavities. The modules each include a light emitting diode having an emission axis and for producing at least some light output generally parallel to the emission axis, an optical device disposed adjacent the light source having a reflective surface for reflecting the light output in directions that are generally perpendicular to the emission axis, and a guide element disposed adjacent the optical device for coupling the reflected light output into the interior of the sign. The guide element includes a second cavity formed therein in which the optical device is disposed. The front surface is illuminated by the coupled light output from the light emitting modules by reflection and/or diffusion inside the sign.
    Type: Grant
    Filed: January 3, 2005
    Date of Patent: February 6, 2007
    Assignee: Leotek Electronics Corporation
    Inventors: Chen-Ho Wu, Chinmau James Hwang, Chin-Wang Tu, Ching Yuan Chung
  • Patent number: 6911915
    Abstract: A high power LED lamp and method for retrofitting conventional traffic signal lamps. The LED lamp includes a housing, a power supply disposed in the housing, a plurality of LEDs mounted to a substantially planar mounting surface in the housing and electrically connected to the power supply for producing diverging light, and a threaded electrical connector extending from the housing. The method includes replacing a conventional incandescent light bulb with the LED lamp, and installing a Fresnel lens inside the traffic signal lamp that collimates and just fills and illuminates the outer lens of the traffic signal lamp.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: June 28, 2005
    Assignee: Leotek Electronics Corporation
    Inventors: Chen H. Wu, Steve Bacilieri, Chao Sung Wang, Shih Chang Wang
  • Patent number: 6905227
    Abstract: A high power LED lamp module for installation in conventional traffic signal lamps includes a housing with a side flange and a spacer ring extending therefrom, a plurality of LEDs disposed inside the housing for producing diverging light, a power supply disposed in the housing between the LEDs and the housing rear wall, a threaded electrical connector extending therefrom, and Fresnel/outer lenses extending across the open end of the spacer ring for collimating the diverging light from the LEDs. The Fresnel lens is disposed a first distance from the light emitting diodes wherein the light collimated thereby just fills and illuminates the entire outer lens. The flange is separated from the rear wall portion by a second distance that does not exceed about 100 mm or about 70mm for a 12 or 8 inch diameter lamp module respectively, to ensure the lamp module fits inside conventional traffic signal lamps.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: June 14, 2005
    Assignee: Leotek Electronics Corporation
    Inventor: Chen H. Wu
  • Patent number: 6761471
    Abstract: A method and apparatus for retrofitting a backlit sign with an LED module. The housing includes sidewalls with translucent portions. The LED module includes linear arrays of LEDs supported by support arms having mounting mechanisms for engaging with the housing sidewalls. The mounting mechanisms include scissor arms rotatably attached together about mid-portions thereof, and a tightening screw that adjusts the distance between the scissor arm ends to press engagement surfaces of the scissor arms against the housing sidewalls. Adjustment screws at the lower ends of the support arm can be adjusted to further extend the engagement surfaces, so that a single LED module can be installed inside a wide range of backlit sign sizes. The retrofit method includes removing the conventional fluorescent lamp from the backlit sign, and installing the LED module using the scissor arm mounting mechanisms.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: July 13, 2004
    Assignee: Leotek Electronics Corporation
    Inventor: Chen H. Wu
  • Patent number: 6558021
    Abstract: A light emitting diode module for attaching to a surface of a sign, which includes a mounting plate having top and bottom surfaces, a plurality of light emitting diodes mounted to the top surface of the mounting plate, a housing having top and bottom surfaces, a first electrical connector attached to the bottom surface of the mounting plate and electrically connected to the plurality of light emitting diodes, a second electrical connector attached to the top surface of the housing for engaging with the first electrical connector, a third electrical connector attached to the housing and electrically connected to the second electrical connector, and a power supply for providing a voltage to the third electrical connector. As the bottom surface of the mounting plate is placed on the top surface of the housing, the first electrical connector engages with the second electrical connector for electrically connecting the plurality of light emitting diodes to the third electrical connector.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: May 6, 2003
    Assignee: Leotek Electronics Corporation
    Inventors: Chen H. Wu, Han-Jen Chuang
  • Patent number: 6502956
    Abstract: An LED lamp including a housing, a circuit board mounted to the housing, an electrical connector attached to the housing and electrically connected to the circuit board, a plurality of LEDs mounted to the circuit board that are activated to emit a light output when an electrical voltage is applied to the electrical connector, and a plurality of LED covers each mounted to cover one of the plurality of LEDs. Each LED cover includes a lens portion that redirects the light output from the one LED, and a side portion that attaches to either the PCB or the LED to secure the LED cover in place. The LED covers can be individually movable or replaced to modify the overall distribution pattern of the LED lamp.
    Type: Grant
    Filed: March 25, 1999
    Date of Patent: January 7, 2003
    Assignee: Leotek Electronics Corporation
    Inventor: Chen H. Wu
  • Patent number: 6481130
    Abstract: A linear array of light emitting diodes with a lens stripe for evenly illuminating signs, which includes a linear array of light emitting diodes (LEDs) for producing a light output, and an elongated lens stripe. The linear array of LEDs includes an elongated mounting member and a plurality of LEDs mounted along the length of the mounting member. The elongated lens stripe is attached to the linear array of LEDs, and includes a reflector portion and a lens portion. The reflector portion has two elongated and opposing side walls that form an elongated channel. The side walls are light reflective. The LEDs are disposed inside the channel. The channel side walls reflect the light output from the LEDs toward the elongated open end of the channel. The lens portion has an elongated lens disposed along the open end of the channel for focusing the light output from the LEDs.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: November 19, 2002
    Assignee: Leotek Electronics Corporation
    Inventor: Chen-Ho Wu
  • Patent number: 6268801
    Abstract: A method and apparatus for retro-fitting a traffic signal lamp with an LED lamp module. The traffic signal lamp has a housing, a front door plate attached to the housing, a lens attached to the front door plate, a reflector in the housing, a threaded electrical socket connector in the housing, and a threaded light bulb connected into the socket connector. The LED lamp including a plurality of light emitting diodes, a power supply electrically connected to the plurality of light emitting diodes, and wires extending from the power supply that terminate in a threaded electrical connector compatible with the socket connector. The method of the present invention includes removing the lens from the front door plate, removing the threaded light bulb from the socket connector, affixing an LED lamp module to the front door plate, and connecting the threaded electrical connector of the LED lamp module to the socket connector.
    Type: Grant
    Filed: June 3, 1999
    Date of Patent: July 31, 2001
    Assignee: Leotek Electronics Corporation
    Inventor: Chen H. Wu
  • Patent number: 6111739
    Abstract: A circuit for driving a plurality of light emitting diodes (LEDs) that includes a power supply and a voltage divide circuit utilizing positive and negative temperature coefficient thermistors to boost the drive voltage to the LEDs as the ambient temperature deviates from room temperature, which compensates for increased electrical resistance of the LEDs at low temperatures and decreased LED light output efficiency at high temperatures. The circuit also provides a signal voltage to indicate the drive current through the LEDs, and includes a transistor to shut down the power supply when the signal voltage drops below a predetermined level (i.e. the number of burned out LEDs exceeds a predetermined number). A compensation circuit utilizes a thermistor to boost the signal voltage as the ambient temperature drops to compensate for the characteristic turn-on voltage of the transistor that increases as the temperature of the transistor drops.
    Type: Grant
    Filed: August 11, 1999
    Date of Patent: August 29, 2000
    Assignee: Leotek Electronics Corporation
    Inventors: Chen-Ho Wu, Han-Jen Chuang
  • Patent number: 5949347
    Abstract: Retrofitting lamps using Light-Emitting Diodes (LEDs) as the illumination source. The lamps are fitted with any one of the common incandescent lamp bases for use as retrofit lamps for illuminated EXIT signs and the like. The LED lamps are electrically powered with a current limiting device to allow LED to operate at a desired current level. The LEDs are arranged on a shaped frame so that they are aimed in directions to provide bright and uniform illumination over an area of the face of the sign that is wider and longer than the width and the length of the lamps.
    Type: Grant
    Filed: August 20, 1997
    Date of Patent: September 7, 1999
    Assignee: Leotek Electronics Corporation
    Inventor: Chen H. Wu
  • Patent number: D373387
    Type: Grant
    Filed: October 31, 1995
    Date of Patent: September 3, 1996
    Assignee: Leotek Electronics Corporation
    Inventor: Chen-Ho Wu
  • Patent number: D385051
    Type: Grant
    Filed: July 10, 1996
    Date of Patent: October 14, 1997
    Assignee: Leotek Electronics Corporation
    Inventor: Chen-Ho Wu
  • Patent number: D388726
    Type: Grant
    Filed: July 10, 1996
    Date of Patent: January 6, 1998
    Assignee: Leotek Electronics Corporation
    Inventor: Chen-Ho Wu
  • Patent number: D424715
    Type: Grant
    Filed: March 25, 1999
    Date of Patent: May 9, 2000
    Assignee: Leotek Electronics Corporation
    Inventor: Chen H. Wu