Lighting device

• US 7,534,002 B2
• Filed: 09/14/2006
• Issued: 05/19/2009
• Est. Priority Date: 09/15/2005
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Yamaguchi, Seiji, Suehiro, Yoshinobu
• Primary Examiner(s): Lee; Y My Quach
• Application Number:
  US11/520,780
• Publication Number:
  US 20070058357A1
• Time in Patent Office: 978 Days
• Field of Search: 362/84, 362/231, 362/237, 362/240, 362/243, 362/244, 362/246, 362/247, 362/249, 362/252, 362/255, 362/256, 362/267, 362/294, 362/800, 257/98, 257/99, 257/100
• US Class Current: 362/84
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• 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 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2924/15174 in different layers of the multilayer substrate
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A lighting device having: a light-emitting diode lamp having a light-emitting diode device sealed by a glass sealing part; and a fluorescent layer disposed on the side of an illuminated object of the light-emitting diode lamp. The fluorescent layer is operable to radiate a wavelength-converted light by being excited by light emitted from the light-emitting diode device.

Claims

1. A lighting device, comprising:

a light-emitting diode lamp comprising a light-emitting diode device sealed by a glass sealing part; and

a fluorescent layer disposed on a side of an illuminated object of the light-emitting diode lamp,

wherein the fluorescent layer radiates a wavelength-converted light by being excited by light emitted from the light-emitting diode device,

wherein a space is formed between the light-emitting diode lamp and the fluorescent layer, and

wherein the light-emitting diode device comprises a p-contact electrode, the p-contact electrode comprising a conductive oxide film comprising a same thermal expansion coefficient as a semiconductor material composing the light-emitting diode device.

2. The lighting device according to claim 1, wherein:

the light-emitting diode lamp further comprises a device-mounting substrate for mounting the light-emitting diode device; and

the lighting device comprises a plurality of the light-emitting diode lamps disposed in lengthwise and crosswise directions on a same plane.

3. The lighting device according to claim 1, wherein:

the light-emitting diode lamp further comprises;

a plurality of the light-emitting diode devices disposed in lengthwise and crosswise directions on a same plane; and

a single device-mounting substrate for mounting the plurality of the light-emitting diode devices; and

the plurality of the light-emitting diode devices are arrayed through the glass sealing part.

4. The lighting device according to claim 1, wherein:

the light-emitting diode lamp further comprises;

a plurality of the light-emitting diode devices disposed in one direction on a same plane; and

a single device-mounting substrate for mounting the plurality of the light-emitting diode devices; and

the lighting device further comprises a transparent member which houses the light-emitting diode lamp therein; and

the transparent member comprises a curved surface.

5. The lighting device according to claim 1, wherein the lighting device further comprises a cover to house the light-emitting diode lamp therein.

6. The lighting device according to claim 5, wherein at least a part of the cover comprises a heat radiation member for mounting a device-mounting substrate to mount the light emitting diode device thereon.

7. The lighting device according to claim 5, wherein:

the cover comprises an annular internal space opening toward the illuminated object; and

a plurality of the light-emitting diode lamps are disposed in the internal space in a circumferential direction.

8. The lighting device according to claim 5, wherein:

the cover comprises a body part comprising a transparent member forming an internal space to house the light-emitting diode lamp therein; and

a power supply part with a screw part for supplying a power supply voltage to the light-emitting diode lamp.

9. The lighting device according to claim 5, wherein:

the cover comprises;

a base part comprising a concave reflection surface to receive light emitted from the light-emitting diode lamp and to reflect the light toward the illuminated object;

a body part comprising an internal space opening on a side of the illuminated object and on an opposite side to the illuminated object; and

a heat radiation wall to divide the internal space into two chambers.

10. The lighting device according to claim 5, wherein:

the cover comprises an internal space opening on a side of the illuminated object and a reflecting surface to receive light emitted from the light-emitting diode lamp and to reflect the light toward the illuminated object in the internal space; and

a plurality of the light-emitting diode lamps are disposed in the internal space in one direction on a same plane.

11. The lighting device according to claim 5, wherein:

the cover comprises;

a plurality of internal spaces opening on a side of the illuminated object and disposed in lengthwise and crosswise directions on a same plane; and

a plurality of reflecting surfaces to receive light emitted from a plurality of the light-emitting diode lamps each corresponding to the internal spaces and to reflect the light toward the illuminated object; and

the plurality of the light-emitting diode lamps are disposed in the plurality of the internal spaces to which each of the light-emitting diode lamps corresponds.

12. The lighting device according to claim 5, wherein:

the fluorescent layer is disposed closely on a side of the light-emitting diode lamp of the cover.

13. The lighting device according to claim 5, wherein:

the cover comprises;

an internal space opening toward the illuminated object; and

a reflecting surface to receive light emitted from the light-emitting diode lamp and to reflect the light toward the illuminated object in the internal space; and

the fluorescent layer is disposed closely on a side of the illuminated object of the glass sealing part.

14. The lighting device according to claim 1, further comprising:

a cover comprising a body part and a lid part,

wherein the cover encloses the light-emitting diode lamp and the fluorescent layer,

wherein the light-emitting diode device emits light of a first wavelength through an internal space to excite the fluorescent layer to radiate the wavelength-converted light, and

wherein the fluorescent layer mixes light of a first wavelength and the wavelength-converted light and discharges light of a second wavelength through the lid part to illuminate the illuminated object.

15. A lighting device, comprising:

a light-emitting diode lamp comprising a light-emitting diode device sealed by a glass sealing part; and

a fluorescent layer disposed on a side of an illuminated object of the light-emitting diode lamp,

wherein the fluorescent layer radiates a wavelength-converted light by being excited by light emitted from the light-emitting diode device,

wherein a space is formed between the light emitting diode lamp and the fluorescent layer, and

wherein the light-emitting diode lamp further comprises a resin material sealing the glass sealing part and a light-diffusing material disposed on the resin material, and

wherein the glass sealing part comprises a rectangular parallelepiped shape.

16. The lighting device according to claim 15, wherein:

the resin material is shaped like a convex lens.