Light emitting diode

• US 20050167682A1
• Filed: 02/03/2005
• Published: 08/04/2005
• Est. Priority Date: 02/04/2004
• Status: Active Grant

• Current Assignee: Citizen Electronics Company Limited
• Original Assignee: Citizen Electronics Company Limited
• Inventors: Fukasawa, Koichi
• Granted Patent: US 7,491,977 B2
• Time in Patent Office: Days
• US Class Current: 257/79
• CPC Class Codes: H01L 2224/48091 Arched
• 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 33/54 having a particular shape
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

An LED comprises: a chip substrate formed with a die bond pattern and electrode terminals; an LED chip mounted on the chip substrate; a reflective frame arranged on the chip substrate to enclose a circumference of the LED chip and having an opening at a part of its side walls and on an upper surface; reflecting surfaces formed on inner circumferential surfaces of the side walls of the reflective frame; a light transmissive resin body formed in the reflective frame and using the opening in the side wall as a light emission face; and a reflecting film covering an upper surface of the light transmissive resin body exposed on an upper surface side of the reflective frame; wherein light produced by the LED chip is reflected by a reflecting surface of the refractive frame and by the reflecting film and is emitted outward from the light emission face. The side emission type LED of this construction can be reduced in thickness for surface mounting and can illuminate a small-width side surface of a liquid crystal panel with high efficiency.

Claims

1. An LED comprising:

a chip substrate formed with a die bond pattern and electrode terminals;

at least one LED chip mounted on the chip substrate;

a reflective frame arranged on the chip substrate to enclose the circumference of the LED chip and having an opening on one part of its side walls and on its upper surface;

reflecting surfaces formed on the inner circumferential surfaces of the side walls of the reflective frame;

a light transmissive resin body formed in the reflective frame and using the opening in the side wall as a light emission face; and

a reflecting film covering the upper surface of the light transmissive resin body exposed on the upper surface side of the reflective frame;

wherein light produced by the LED chip is reflected by the reflecting surfaces of the reflective frame and by the reflecting film and is emitted outward from the light emission face.

2. An LED according to claim 1, wherein the reflective frame has a U-shaped reflecting surface that encloses the circumference of the LED chip mounted on the chip substrate from three directions, or a V-shaped or arc-shaped reflecting surface that encloses the LED chip from two directions.

3. An LED according to claim 1, wherein the reflective frame has a plurality of light emission faces formed therein so that they are directed in the same direction.

4. An LED according to claim 1, wherein the reflective frame is a molded resin member containing reflective particles, or a formed metal member or molded resin member provided with a reflective plating on its surface.

5. An LED according to claim 1, wherein the reflecting film is a thin metal film or coated film formed on the upper surface of the light transmissive resin body.

6. An LED according to claim 1, wherein the LED chip is made up of a plurality of LED chips of different illumination colors arranged in line on the chip substrate toward the light emission face.

7. An LED according to claim 6, wherein the LED chip is made up of a green LED chip , a blue LED chip and a red LED chip.

8. An LED according to claim 7, wherein the red LED chip is disposed at a position farthest from the light emission face.

9. An LED according to claim 1, wherein the LED chip is formed by a blue LED chip which is sealed in a light transmissive resin body containing phosphor pigments to produce a white light.