Light emitting diode display with PCB base

• US 5,119,174 A
• Filed: 10/26/1990
• Issued: 06/02/1992
• Est. Priority Date: 10/26/1990
• Status: Expired due to Fees

• Current Assignee: Hi Sharp Electronics Co., Ltd.
• Original Assignee: Hi Sharp Electronics Co., Ltd.
• Inventors: Chen, Der-Jong
• Primary Examiner(s): Hille, Rolf
• Assistant Examiner(s): OSTROWSKI, DAVID M
• Application Number:
  US07/604,072
• Time in Patent Office: 585 Days
• Field of Search: 357/80, 357/74, 357/17, 357/81, 357/75, 361/387, 361/388, 362/373, 362/800
• US Class Current: 257/98
• CPC Class Codes: G09F 9/33 being semiconductor devices, e.g. diodes
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H05K 1/02 Details
• CPC Class Codes: H05K 1/182 associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A light emitting diode display with PCB base, LED members affixed thereon by conductive epoxy, and bonding wire, wherein the PCB is punched with reflector dish on each LED die attach zone so as to reflect and concentrate the light emitted from the LED to increase the luminous intensity of the display, and near each die attach zone is formed a plating through hole to increase the heat-dispersing area of the LED and improve the stability of the forward voltage and wave length (color) of the LED and decrease the light output degradation of the LED to prolong the life of the display.

Claims

1. A lighting display comprising:

a circuit board having a first face and a second face, a plurality of bowl-shaped cavities in said first face, through holes extending between said faces;

said cavities and said holes being arranged in a regular pattern, so that there is a single hole associated with each cavity;

individual thermally conductive foil islands (21) covering preselected areas of the first face of the circuit board;

each foil island covering only one of the bowl-shaped cavities and a surrounding area of said first face;

each foil island circumscribing an associated through hole;

each through hole having a thermally conductive lining forming a bridge between the associated foil island and said first thermally conductive foil;

a light emitting diode crystal bonded to each foil island at a central point in the associated cavity, whereby the foil in each cavity serves as a light reflector;

foil terminal means (13) on said first face of the circuit board isolated from said foil islands; and

a lead wire (16) extending from each crystal to said terminal means.