LIGHT EMITTING MODULE

• US 20130105850A1
• Filed: 12/21/2012
• Published: 05/02/2013
• Est. Priority Date: 07/26/2010
• Status: Active Grant

• Current Assignee: Koito Manufacturing Company Limited
• Original Assignee: Koito Manufacturing Company Limited
• Inventors: DAICHO, Hisayoshi, TSUTSUMI, Yasuaki, KOMATSU, Takaaki
• Granted Patent: US 8,704,261 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: F21S 41/143 the main emission direction of the LED being parallel to the optical axis of the illuminating device
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body

Abstract

A light emitting module includes: an LED chip; a plate-shaped phosphor layer that is provided so as to face the light emitting surface of the LED chip and is configured to convert the wavelength of the light emitted by the LED chip; and a filter layer that is formed, of the surfaces of the phosphor layer, on at least one of the surface that faces the LED chip and the side surface, and that is configured to transmit the light emitted from the LED chip and to reflect the light whose wavelength has been converted by the phosphor layer. The filter layer is formed such that a ratio of the energy of the emitted light within a range of ±60° with respect to the front direction to the total energy of emitted light is 80% or more.

Claims

1. A light emitting module comprising:

a semiconductor light emitting element;

a plate-shaped light wavelength conversion member that is provided so as to face the light emitting surface of the semiconductor light emitting element and is configured to convert the wavelength of the light emitted by the semiconductor light emitting element; and

a filter layer that is formed, of the surfaces of the plate-shaped light wavelength conversion member, on at least one of the surface facing the semiconductor light emitting element and the side surface and is configured to transmit the light emitted from the semiconductor light emitting element and to reflect the light whose wavelength has been converted by the light wavelength conversion member, wherein

the semiconductor light emitting element is formed such that a ratio of the energy of the emitted light within a range of ±

60°

with respect to the front direction to the total energy of emitted light is 80% or more.

2. The light emitting module according to claim 1, further comprising an adhesive layer that adheres the filter layer and the semiconductor light emitting element, wherein

the filter layer is formed, of the surfaces of the light wavelength conversion member, on the surface that faces the semiconductor light emitting element, and wherein

the adhesive contains a material having a refractive index of 1.3 or more.

3. The light emitting module according to claim 2, wherein

the thickness of the adhesive layer is 0.1 μ

m to 100 μ

m.

4. The light emitting module according to claim 1, wherein

the filter layer is formed such that the transmittance, occurring when the light emitted by the semiconductor light emitting element is incident on the filter layer at an incident angle of 60°

, is 80% or more.

5. The light emitting module according to claim 1, wherein

at least part of the surface of the light wavelength conversion member, on which the filter layer is not formed, has a concavo-convex shape.

6. The light emitting module according to claim 5, wherein

the concavo-convex shape is formed of a plurality of grooves, and wherein

the width of the groove is 1 μ

m to 1000 μ

m and the depth thereof is 1 μ

m to 1000 μ

m.

7. The light emitting module according to claim 1, wherein

the arithmetic average roughness Ra in at least part of the surface of the light wavelength conversion member, on which the filter layer is not formed, is 100 nm to 1000 nm.

8. The light emitting module according to claim 1, wherein

when it is assumed that:

the number of the semiconductor light emitting elements included in the light emitting module is N;

the area of the light emitting surface of each of the semiconductor light emitting elements, the light emitting surface being located on the side that faces the filter layer, is S; and

the area of the light incident surface of the light wavelength conversion member, the light incident surface being located on the side that faces the semiconductor light emitting element, is T, S≦

T/N≦

4×

S is satisfied.

9. The light emitting module according to claim 1, wherein

the thickness of the light wavelength conversion member is 1 μ

m to 1000 μ

m.

10. The light emitting module according to claim 1, wherein

when it is assumed that:

the wavelength of light, occurring when the transmittance becomes 50% in the case where light is incident on the filter layer at an incident angle of 0°

, is λ

1 [nm]; and

the peak wavelength of the light emitted by the semiconductor light emitting element is λ

p [nm], the filter layer is formed so as to satisfy λ

p≦

λ

1≦

λ

p+200 [nm].

11. The light emitting module according to claim 2, wherein

the filter layer is formed such that the transmittance, occurring when the light emitted by the semiconductor light emitting element is incident on the filter layer at an incident angle of 60°

, is 80% or more.

12. The light emitting module according to claim 3, wherein

the filter layer is formed such that the transmittance, occurring when the light emitted by the semiconductor light emitting element is incident on the filter layer at an incident angle of 60°

, is 80% or more.

13. The light emitting module according to claim 2, wherein

at least part of the surface of the light wavelength conversion member, on which the filter layer is not formed, has a concavo-convex shape.

14. The light emitting module according to claim 3, wherein

at least part of the surface of the light wavelength conversion member, on which the filter layer is not formed, has a concavo-convex shape.

15. The light emitting module according to claim 2, wherein

the arithmetic average roughness Ra in at least part of the surface of the light wavelength conversion member, on which the filter layer is not formed, is 100 nm to 1000 nm.

16. The light emitting module according to claim 3, wherein

the arithmetic average roughness Ra in at least part of the surface of the light wavelength conversion member, on which the filter layer is not formed, is 100 nm to 1000 nm.

17. The light emitting module according to claim 2, wherein

when it is assumed that:

the number of the semiconductor light emitting elements included in the light emitting module is N;

the area of the light emitting surface of each of the semiconductor light emitting elements, the light emitting surface being located on the side that faces the filter layer, is S; and

the area of the light incident surface of the light wavelength conversion member, the light incident surface being located on the side that faces the semiconductor light emitting element, is T, S≦

T/N≦

4×

S is satisfied.

18. The light emitting module according to claim 3, wherein when it is assumed that:

the number of the semiconductor light emitting elements included in the light emitting module is N;

the area of the light emitting surface of each of the semiconductor light emitting elements, the light emitting surface being located on the side that faces the filter layer, is S; and

the area of the light incident surface of the light wavelength conversion member, the light incident surface being located on the side that faces the semiconductor light emitting element, is T, S≦

T/N≦

4×

S is satisfied.

19. The light emitting module according to claim 2, wherein

when it is assumed that:

the wavelength of light, occurring when the transmittance becomes 50% in the case where light is incident on the filter layer at an incident angle of 0°

, is λ

1 [nm]; and

the peak wavelength of the light emitted by the semiconductor light emitting element is λ

p [nm], the filter layer is formed so as to satisfy λ

p≦

λ

1≦

λ

p+200 [nm].

20. The light emitting module according to claim 3, wherein

when it is assumed that:

the wavelength of light, occurring when the transmittance becomes 50% in the case where light is incident on the filter layer at an incident angle of 0°

, is λ

1 [nm]; and

the peak wavelength of the light emitted by the semiconductor light emitting element is λ

p [nm], the filter layer is formed so as to satisfy λ

p≦

λ

1≦

λ

p+200 [nm].