Lighting source using solid state emitter and phosphor materials

• US 8,960,953 B2
• Filed: 02/04/2013
• Issued: 02/24/2015
• Est. Priority Date: 05/05/2004
• Status: Active Grant

• Current Assignee: Rensselaer Polytechnic Institute
• Original Assignee: Rensselaer Polytechnic Institute
• Inventors: Narendran, Nadarajah, Gu, Yimin
• Primary Examiner(s): PAYNE, SHARON E
• Application Number:
  US13/758,362
• Publication Number:
  US 20130194779A1
• Time in Patent Office: 750 Days
• Field of Search: 362/310, 362/296.01, 362/297, 313/501
• US Class Current: 362/231
• CPC Class Codes: F21K 2/00 Non-electric light sources using luminescence using excitation by radioactivity G21H3/02, H01J65/06, H01J65/08; using excitation by an external electromagnetic field or by external corpuscular radiation H01J65/04; Light sources using electrochemiluminescence
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21V 5/004 using microlenses
• CPC Class Codes: F21V 7/06 with parabolic curvature
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• CPC Class Codes: F21V 9/32 characterised by the arrangement of the photoluminescent material
• CPC Class Codes: F21V 9/38 Combination of two or more photoluminescent elements of different materials
• CPC Class Codes: F21V 9/45 by adjustment of photoluminescent elements
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: F21Y 2115/30 Semiconductor lasers
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2933/0091 Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• 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
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

A light emitting apparatus has a light source for emitting a first light in a forward direction. A wavelength-converting layer is spaced apart from the light source and disposed in a path of the first light. The wavelength-converting layer is configured to absorb at least a portion of the first light and emit a second light. A reflective layer is configured to be reflective of at least the second light, and the wavelength-converting layer is disposed between the reflective layer and the light source.

Claims

1. A light-emitting apparatus, comprising:

a light source;

a structure having a top surface connected to the light source and a bottom surface being a lowest surface of the light-emitting apparatus right beneath the light source;

a reflector separated from the structure, and having a reflective surface right above the top surface; and

a phosphor layer separated from the reflector, and having an inner surface facing the light source and an outer surface for radiating a light striking the reflector.

2. The light-emitting apparatus of claim 1, further comprising a transparent medium between the phosphor layer and the reflector.

3. The light-emitting apparatus of claim 1, further comprising an optic element associated with the phosphor layer and arranged between the light source and the reflector.

4. The light-emitting apparatus of claim 1, wherein the phosphor layer is arranged in a curved shape.

5. The light-emitting apparatus of claim 1, wherein the phosphor layer and the reflector are arranged in a similar geometric shape.

13. The light-emitting apparatus of claim 1, wherein the phosphor layer is configured to covert light from the light source into forward transferred radiation and back transferred radiation, the reflector is configured to reflect the forward transferred radiation.

14. The light-emitting apparatus of claim 13, wherein the back transferred radiation is substantially not reflected by the reflector.

15. The light-emitting apparatus of claim 1, wherein the light-emitting apparatus has a luminous efficacy over 80 lm/W.

6. A light-emitting apparatus, comprising:

one or more light emitters configured to emit a first light, and having a front surface, a rear surface, a right surface, and a left surface;

a base having a plane facing the rear surface;

a wall arranged near the base, and having an inner surface and outer surface; and

a phosphor layer arranged over the front surface without overlapping the wall, and excited by the first light to induce a second light which is directed to enter the wall from the inner surface and exit the wall from the outer surface.

7. The light-emitting apparatus of claim 6, wherein the wall is inclined against the plane by an angle greater than 90 degree.

8. The light-emitting apparatus of claim 6, wherein the wall is arranged over the right surface or the left surface.

9. The light-emitting apparatus of claim 6, wherein the first light has a narrow beam and impinges on the phosphor layer.

10. The light-emitting apparatus of claim 6, wherein the one or more light emitters are arranged in an array.

11. The light-emitting apparatus of claim 6, wherein the phosphor layer is bonded to a transparent material.

12. The light-emitting apparatus of claim 6, wherein the phosphor layer is placed within a transparent material.