Thin-light emitting diode lamp, and method of manufacturing the same

• US 8,004,002 B2
• Filed: 12/27/2006
• Issued: 08/23/2011
• Est. Priority Date: 01/04/2006
• Status: Expired due to Fees

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Okazaki, Tomokazu
• Primary Examiner(s): Jackson, Jr.; Jerome
• Application Number:
  US12/160,051
• Publication Number:
  US 20090206353A1
• Time in Patent Office: 1,700 Days
• Field of Search: 257/98
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• 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 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/54 having a particular shape

Abstract

A thin-type light emitting diode lamp includes a blue light emitting diode chip (6) disposed at a substantial center of an inner bottom surface of a groove-shaped recess (3) formed at an end surface and having a thin elongated rectangular opening, a red light conversion layer (7) covering the blue light emitting diode chip (6) and made of a light-transmitting synthetic resin containing powder of a red fluorescent material which emits red light when excited by blue light emitted from the blue light emitting diode chip, and a green light conversion layer (10) made of a light-transmitting synthetic resin containing powder of a green fluorescent material which emits green light when excited by the blue light. The light emitting diode lamp further includes a light transmitting layer (9) intervening between the red light conversion layer (7) and the green light conversion layer (10). The light transmitting layer contains neither the red fluorescent material nor the green fluorescent material or contains the red fluorescent material or the green fluorescent material only by a small amount.

Claims

1. A thin-type light emitting diode lamp comprising:

a lamp body including an end surface formed with a groove-shaped recess having a thin elongated rectangular opening;

a blue light emitting diode chip disposed at a substantial center of an inner bottom surface of the recess of the lamp body;

a red light conversion layer covering the blue light emitting diode chip and made of a light-transmitting synthetic resin containing powder of a red fluorescent material which emits red light when excited by blue light emitted from the blue light emitting diode chip; and

a green light conversion layer made of a light-transmitting synthetic resin containing powder of a green fluorescent material which emits green light when excited by the blue light;

wherein the light emitting diode lamp further comprises a light transmitting layer intervening between the red light conversion layer and the green light conversion layer, the light transmitting layer containing neither the red fluorescent material nor the green fluorescent material or contains the red fluorescent material or the green fluorescent material by an amount smaller than that contained in the red light conversion layer or the green light conversion layer,

wherein the red light conversion layer is thicker at portions directly contacting two side surfaces of the blue light emitting diode chip which extend perpendicularly to a longitudinal direction of the recess than at portions directly contacting other two side surfaces of the blue light emitting diode chip which extend in the longitudinal direction of the recess.

2. The thin-type light emitting diode lamp according to claim 1, wherein the light transmitting layer comprises a space.

3. The thin-type light emitting diode lamp according to claim 1, wherein the light transmitting layer is made of a light-transmitting synthetic resin.

4. A method of making a thin-type light emitting diode lamp, the method comprising:

a first step of forming a red light conversion layer to cover a blue light emitting diode chip by using a light-transmitting synthetic resin containing powder of a red fluorescent material which emits red light when excited by blue light emitted from the blue light emitting diode chip;

a second step of mounting the blue light emitting diode chip at a substantial center of an inner bottom surface of a groove-shaped recess formed at an end surface of a lamp body; and

a third step of forming a green light conversion layer on an outer side of the red light conversion layer by using a light-transmitting synthetic resin containing powder of a green fluorescent material which emits green light when excited by the blue light;

wherein, in the first step, the red light conversion layer is formed to be thicker at portions directly contacting two side surfaces of the blue light emitting diode chip which extend perpendicularly to a longitudinal direction of the recess than at portions directly contacting other two side surfaces of the blue light emitting diode chip which extend in the longitudinal direction of the recess.

5. The method of making a thin-type light emitting diode lamp according to claim 4, wherein the third step comprises the step of injecting a light-transmitting synthetic resin in a liquid state containing powder of a green fluorescent material into the groove-shaped recess, the step of maintaining a posture in which an opening of the groove-shaped recess is oriented downward, and the step of hardening the light-transmitting synthetic resin in the liquid state while keeping the posture.