Vehicular lamp employing led light sources

• US 6,848,820 B2
• Filed: 03/06/2003
• Issued: 02/01/2005
• Est. Priority Date: 03/15/2002
• Status: Expired due to Fees

• Current Assignee: Koito Manufacturing Company Limited
• Original Assignee: Koito Manufacturing Company Limited
• Inventors: Natsume, Kazunori
• Primary Examiner(s): CARIASO, ALAN B
• Application Number:
  US10/379,810
• Publication Number:
  US 20030174514A1
• Time in Patent Office: 698 Days
• Field of Search: 362/240, 362/241, 362/245, 362/247, 362/297, 362/348, 362/544, 362/545, 362/346
• US Class Current: 362/545
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 43/15 Strips of light sources
• CPC Class Codes: F21S 43/26 Refractors, transparent cover plates, light guides or filters not provided in groups F21S43/235 - F21S43/255
• CPC Class Codes: F21S 43/40 characterised by the combination of reflectors and refractors
• CPC Class Codes: F21V 7/0008 providing for indirect lighting
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A vehicular lamp employing a plurality of LED light sources and arranged to emit light using indirect illumination wherein the total light emittance in the front direction of the lamp is increased by more effectively using the light from the LED light sources. The LED light sources are arranged in a line in the vertical direction such that their direction of light emission is toward the rear of the lamp. The reflecting surface of the reflector is divided into right and left reflecting areas by a boundary line. With this arrangement, a large portion of the light from each LED light source contributes to the light reflected by the reflector. The reflecting areas are divided into a plurality of small reflecting surfaces, preferably two for each LED light source. Thus, it is possible to separately control the reflection of the light from each LED light source by the small reflecting surfaces on both sides of the LED light sources. When the lamp is observed from the front, the number of illuminated areas is greater than the number of LED light sources.

Claims

1. A vehicular lamp comprising:

a plurality of LED light sources, a reflector for reflecting light from said LED light sources toward the front of the lamp, and a translucent cover provided at a front side of said reflector, the plurality of LED light sources being arranged in a line and mounted such that their respective light output beams are directed toward said reflector, a reflecting surface of said reflector being divided into two reflecting areas by a boundary line extending substantially parallel to said line along which said plurality of the LED light sources are arranged, and each of said reflecting areas being divided, substantially transversely to the boundary line, into a plurality of small reflecting surfaces, two of said small reflecting surfaces being provided for each of said LED light sources.

2. The vehicular lamp according to claim 1, wherein said boundary line bisects an illumination angle of each of said LED light sources.

3. The vehicular lamp according to claim 1, wherein said line along which said plurality of LED light sources are arranged is substantially straight.

4. The vehicular lamp according to claim 1, wherein each of said small reflecting surfaces has a concave surface shape having a greater curvature than a paraboloid of revolution having the optical axis of the corresponding small reflecting surface as its central axis and the position of the corresponding LED light source as its focus.

5. The vehicular lamp according to claim 1, further comprising a cover member for covering said LED light sources, said cover member being provided at a front side of said plurality of LED light sources, said cover member comprising a translucent member having a substantially U-shaped horizontal section perpendicular to said boundary line, and said cover member being disposed with end faces of said cover member being directed toward the rear of said lamp.

6. The vehicular lamp according to claim 5, wherein said reflector comprises, for each of said LED light sources, a pair of elongated reflecting surfaces formed on said reflecting surface on opposite sides of said boundary line for reflecting light from the corresponding LED light source toward respective ones of said end faces of said cover member.

7. The vehicular lamp according to claim 6, wherein said elongated reflecting surfaces reflect light without substantial diffusion in horizontal and vertical directions.

8. The vehicular lamp according to claim 1, wherein said reflecting surfaces are substantially equal in size.

9. The vehicular lamp according to claim 1, wherein said small reflecting surfaces are substantially rectangular in configuration and have a long side extending in a horizontal direction.

10. The vehicular lamp according to claim 1, further comprising a cylindrical lens provided at a rear side of each of said LED light sources for condensing light from the corresponding LED light source.

11. The vehicular lamp according to claim 10, wherein said cylindrical lens has Fresnel lensing in vertical cross section and a circular configuration in horizontal cross section.

12. A vehicular lamp comprising:

a plurality of LED light sources, a reflector for reflecting light from said LED light sources toward the front of the lamp, and a translucent cover provided at a front side of said reflector, the plurality of LED light sources being arranged in a line and mounted such that their respective light output beams are directed toward said reflector, a reflecting surface of said reflector being divided into two reflecting areas by a boundary line extending substantially parallel to said line along which said plurality of the LED light sources are arranged, each of said reflecting areas being divided into a plurality of small reflecting surfaces, and each of said small reflecting surfaces being divided into a plurality of smaller reflecting elements.

13. The vehicular lamp according to claim 12, wherein said boundary line bisects an illumination angle of each of said LED light sources.

14. The vehicular lamp according to claim 12, wherein said line along which said plurality of LED light sources are arranged is substantially straight.

15. The vehicular lamp according to claim 12, wherein each of said smaller reflecting elements has a concave surface shape having a greater curvature than a paraboloid of revolution having the optical axis of the corresponding small reflecting surface as its central axis and the position of the corresponding LED light source as its focus.

16. The vehicular lamp according to claim 12, further comprising a cover member for covering said LED light sources, said cover member being provided at a front side of said plurality of LED light sources, said cover member comprising a translucent member having a substantially U-shaped horizontal section perpendicular to said boundary line, and said cover member being disposed with end faces of said cover member being directed toward the rear of said lamp.

17. The vehicular lamp according to claim 12, wherein said reflecting surfaces are substantially equal in size.

18. The vehicular lamp according to claim 12, wherein said small reflecting surfaces are substantially rectangular in configuration and have a long side extending in a horizontal direction.

19. The vehicular lamp according to claim 12, further comprising a cylindrical lens provided at a rear side of each of said LED light sources for condensing light from the corresponding LED light source.

26. The vehicular lamp according to claim 12, wherein each of said reflecting areas are divided, substantially transversely to the boundary line, into the plurality of small reflecting surfaces.

20. A vehicular lamp comprising:

a plurality of LED light sources, a reflector for reflecting light from said LED light sources toward the front of the lamp, and a translucent cover provided at a front side of said reflector, the plurality of LED light sources being arranged in a line and mounted such that their respective light output beams are directed toward said reflector, a reflecting surface of said reflector being divided into two reflecting areas by a boundary line extending substantially parallel to said line along which said plurality of the LED light sources are arranged, and each of said reflecting areas being divided into a plurality of small reflecting surfaces, two of said small reflecting surfaces being provided for each of said LED light sources,

wherein each of said small reflecting surfaces has a concave surface shape having a greater curvature than a paraboloid of revolution having the optical axis of the corresponding small reflecting surface as its central axis and the position of the corresponding LED light source as its focus.

21. A vehicular lamp comprising:

a plurality of LED light sources, a reflector for reflecting light from said LED light sources toward the front of the lamp, and a translucent cover provided at a front side of said reflector, the plurality of LED light sources being arranged in a line and mounted such that their respective light output beams are directed toward said reflector, a reflecting surface of said reflector being divided into two reflecting areas by a boundary line extending substantially parallel to said line along which said plurality of the LED light sources are arranged, and each of said reflecting areas being divided into a plurality of small reflecting surfaces, two of said small reflecting surfaces being provided for each of said LED light sources,

said lamp further comprising a cover member for covering said LED light sources, said cover member being provided at a front side of said plurality of LED light sources, said cover member comprising a translucent member having a substantially U-shaped horizontal section perpendicular to said boundary line, and said cover member being disposed with end faces of said cover member being directed toward the rear of said lamp.

22. The vehicular lamp according to claim 21, wherein said reflector comprises, for each of said LED light sources, a pair of elongated reflecting surfaces formed on said reflecting surface on opposite sides of said boundary line for reflecting light from the corresponding LED light source toward respective ones of said end faces of said cover member.

23. The vehicular lamp according to claim 22, wherein said elongated reflecting surfaces reflect light without substantial diffusion in horizontal and vertical directions.

24. A vehicular lamp comprising:

a plurality of LED light sources, a reflector for reflecting light from said LED light sources toward the front of the lamp, and a translucent cover provided at a front side of said reflector, the plurality of LED light sources being arranged in a line and mounted such that their respective light output beams are directed toward said reflector, a reflecting surface of said reflector being divided into two reflecting areas by a boundary line extending substantially parallel to said line along which said plurality of the LED light sources are arranged, and each of said reflecting areas being divided into a plurality of small reflecting surfaces, two of said small reflecting surfaces being provided for each of said LED light sources,

said lamp further comprising a cylindrical lens provided at a rear side of each of said LED light sources for condensing light from the corresponding LED light source.

25. The vehicular lamp according to claim 24, wherein said cylindrical lens has Fresnel lensing in vertical cross section and a circular configuration in horizontal cross section.

27. A vehicular lamp comprising:

a plurality of LED light sources, a reflector for reflecting light from said LED light sources toward the front of the lamp, and a translucent cover provided at a front side of said reflector, the plurality of LED light sources being arranged in a line and mounted such that their respective light output beams are directed toward said reflector, a reflecting surface of said reflector being divided into two reflecting areas by a boundary line extending substantially parallel to said line along which said plurality of the LED light sources are arranged, and each of said reflecting areas being divided into a plurality of small reflecting surfaces, two of said small reflecting surfaces being provided for each of said LED light sources,

wherein the light reflected by the reflector passes along both sides of the plurality of LED light sources being arranged in a line.