IP Library Granted Patent US 7,539,223
Granted Patent B2
US 7,539,223 · App. 11/524,259 · Granted May 26, 2009

Light emitting device

Assignee: Sanyo Electric Co., Ltd.
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Quick Facts
Patent No.
US 7,539,223
App. No.
11/524,259
Granted
May 26, 2009
Kind
B2
Abstract

A light emitting device includes a light emitting element which emits light with a first wavelength; and a light emitting conversion unit for converting the light with the first wavelength by using wavelength conversion materials including a short wavelength conversion material and a long wavelength conversion material, the short wavelength conversion material being that which emits light with a second wavelength longer in wavelength than the light with the first wavelength, by absorbing the light with the first wavelength, and the long wavelength conversion material being that which emits light with a wavelength longer than the second wavelength by absorbing the light with the first wavelength. A proportion of the short wavelength conversion material of the wavelength conversion materials included in a first region is smaller than that of the short wavelength conversion material of the wavelength conversion materials included in the entire light emitting conversion unit, and a proportion of the short wavelength conversion material of the wavelength conversion materials included in a second region is larger than that of the short wavelength conversion material of the wavelength conversion materials included in the entire light emitting conversion unit.

Claims (24)

1. A light emitting device, comprising:

a light emitting element configured to emit light with a first wavelength; and

a light emitting conversion unit configured to convert the light with the first wavelength by using wavelength conversion materials including a short wavelength conversion material and a long wavelength conversion material, the short wavelength conversion material emits light with a second wavelength longer in wavelength than the light with the first wavelength by absorbing the light with the first wavelength, and the long wavelength conversion material emits light with a wavelength longer than the second wavelength by absorbing the light with the first wavelength,

wherein a proportion of the short wavelength conversion material of the wavelength conversion materials included in a first region of the light emitting conversion unit is smaller than a proportion of the short wavelength conversion material of the wavelength conversion materials included in the entire light emitting conversion unit, and

a proportion of the short wavelength conversion material of the wavelength conversion materials included in a second region, which is a region more distant from the light emitting element than the first region in the light emitting conversion unit, is larger than a proportion of the short wavelength conversion material of the wavelength conversion materials included in the entire light emitting conversion unit, and

wherein the short wavelength conversion material is included more in the second region than the long wavelength conversion material.

2. A light emitting device, comprising:

a light emitting element configured to emit light with a first wavelength;

a light emitting conversion unit configured to convert the light with the first wavelength by using wavelength conversion materials including a short wavelength conversion material and a long wavelength conversion material, the short wavelength conversion material emits light with a second wavelength longer in wavelength than the light with the first wavelength by absorbing the light with the first wavelength, and the long wavelength conversion material emits light with a wavelength longer than the second wavelength by absorbing the light with the first wavelength, and,

a wavelength selecting material, which penetrates light with a wavelength longer than the first and the second wavelengths, and which reflects the light with the second wavelength, the wavelength selecting material is provided between the first region and the second region,

wherein a proportion of the short wavelength conversion material of the wavelength conversion materials included in a first region of the light emitting conversion unit is smaller than a proportion of the short wavelength conversion material of the wavelength conversion materials included in the entire light emitting conversion unit, and

a proportion of the short wavelength conversion material of the wavelength conversion materials included in a second region, which is a region more distant from the light emitting element than the first region in the light emitting conversion unit, is larger than a proportion of the short wavelength conversion material of the wavelength conversion materials included in the entire light emitting conversion unit.

3. The light emitting device according to claim 1 , further comprising a wavelength selecting material, which penetrates light with a wavelength longer than the first and the second wavelengths, and which reflects the light with the second wavelength, the wavelength selecting material is provided between the first region and the second region.

4. The light emitting device according to claim 2 , wherein each of the first region, the second region, and the wavelength selecting material is formed in a sheet form.

5. The light emitting device according to claim 3 , wherein each of the first region, the second region, and the wavelength selecting material is formed in a sheet form.

6. A light emitting device, comprising:

a light emitting element configured to emit light with a first wavelength; and

a light emitting conversion unit configured to convert the light with the first wavelength by using wavelength conversion materials including a short wavelength conversion material and a long wavelength conversion material, the short wavelength conversion material emits light with a second wavelength longer in wavelength than the light with the first wavelength by absorbing the light with the first wavelength, and the long wavelength conversion material emits light with a wavelength longer than the second wavelength by absorbing the light with the first wavelength,

wherein a proportion of the short wavelength conversion material of the wavelength conversion materials included in a first region of the light emitting conversion unit is smaller than a proportion of the short wavelength conversion material of the wavelength conversion materials included in the entire light emitting conversion unit, and

a proportion of the short wavelength conversion material of the wavelength conversion materials included in a second region, which is a region more distant from the light emitting element than the first region in the light emitting conversion unit, is larger than a proportion of the short wavelength conversion material of the wavelength conversion materials included in the entire light emitting conversion unit, and

wherein said first region and said second region each comprise an amount of short and long wavelength conversion material and wherein in the first region the proportion of long wavelength conversion material is greater than the proportion of the short wavelength material and in the second region the proportion of short wavelength conversion material is greater than the proportion of the long wavelength conversion material.

7. The light emitting device of claim 6 , further comprising:

a wavelength selecting material, which penetrates light with a wavelength longer than the first and the second wavelengths, and which reflects the light with the second wavelength, the wavelength selecting material is provided between the first region and the second region.

8. The light emitting device of claim 7 , wherein each of the first region, the second region, and the wavelength selecting material is formed in a sheet form.

Assignments (4)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 20, 2017
From: SANYO ELECTRIC CO., LTD.
To: EPISTAR CORPORATION
Reel/Frame 041652/0122 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 1, 2016
From: FUTURE LIGHT LIMITED LIABILITY COMPANY
To: SANYO ELECTRIC CO., LTD.
Reel/Frame 040523/0797 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 30, 2012
From: SANYO ELECTRIC CO., LTD.
To: FUTURE LIGHT, LLC
Reel/Frame 027957/0258 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 21, 2006
From: TOKUNAGA, SEIICHI
To: SANYO ELECTRIC CO., LTD.
Reel/Frame 018328/0707 →
Priority Claims (1)
JP 2005-276056 · Sep 22, 2005 · national
Continuity (1)
Related Publication 20070064751A1 · Mar 22, 2007