Lighting device

• US 20060083002A1
• Filed: 10/13/2005
• Published: 04/20/2006
• Est. Priority Date: 10/14/2004
• Status: Active Grant

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: Owada, Ryotaro, Koike, Teruo, Bamba, Shoichi
• Granted Patent: US 7,625,102 B2
• Time in Patent Office: Days
• US Class Current: 362/326
• 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: F21S 41/147 the main emission direction of the LED being angled to the optical axis of the illuminating device
• CPC Class Codes: F21S 41/151 arranged in one or more lines
• CPC Class Codes: F21S 41/28 Cover glass
• 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 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21W 2131/103 of streets or roads
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A lighting device can have a simple configuration which can be formed compactly in the direction of its optical axis in particular, and with a light weight. The lighting device can also have a functional, three-dimensional innovative appearance for the sake of enhanced merchantability and novelty. The lighting device can include a light source and a projection lens which is situated so that its source-side focus lies near the light source and its optical axis generally coincides with that of the light source. The projection lens can be a distribution control lens of convex form, having an exit surface shaped aspherically so that the direction of emission is continuously refracted into specified directions with respect to the angle of incidence from the focal position.

Claims

1. A lighting device comprising:

at least one light source having an optical axis; and

a projection lens having an optical axis and a source-side focal position, the projection lens located adjacent said light source so that the source-side focal position is located substantially at said light source and the optical axis of the projection lens substantially coincides with the optical axis of said light source, said projection lens being a distribution control lens of convex form having an exit surface that is aspherically shaped so that a direction of emission light is continuously refracted into a certain direction with respect to an angle of incidence of light originating from the focal position.

4. The lighting device according to claim 1, wherein said projection lens functions as a convex lens in a first direction perpendicular to the optical axis, and emits light diffused in a second direction perpendicular to both the optical axis and the first direction.

7. The lighting device according to claim 4, wherein said projection lens refracts the light in the second direction so that an angle of emission of the emitted light has a predetermined ratio to an angle of incidence of the light originating from the focal position.

10. The lighting device according to claim 1, wherein said light source is a light emitting device.

13. The lighting device according to claim 4, wherein said light source is a light emitting device.

14. The lighting device according to claim 7, wherein said light source is a light emitting device.

15. The lighting device according to claim 10, wherein said light source is a light emitting diode.

18. The lighting device according to claim 13, wherein said light source is a light emitting diode.

19. The lighting device according to claim 14, wherein said light source is a light emitting diode.

2. A lighting device comprising:

at least one light source having an optical axis;

a reflecting member located adjacent said light source, the reflecting member having a reflecting surface that has a first focal position, a second focal position, and a major axis, the reflecting surface being situated so that the first focal position of the reflecting surface is located substantially at said light source and the major axis of the reflecting surface substantially coincides with the optical axis of said light source; and

a projection lens having an optical axis and a focus, the projection lens situated so that the focus of the projection lens is located substantially at the second focal position of said reflecting surface, and the optical axis of the projection lens substantially coincides with the major axis of said reflecting surface, said projection lens being a distribution control lens of convex form having an exit surface that is aspherically shaped so that a direction of emission light is continuously refracted into a certain direction with respect to an angle of incidence of light originating from the second focal position.

3. The lighting device according to claim 2, wherein said reflecting member is arranged only in an area forward of said light source.

5. The lighting device according to claim 2, wherein said projection lens functions as a convex lens in a first direction perpendicular to the optical axis, and emits light diffused in a second direction perpendicular to both the optical axis and the first direction.

6. The lighting device according to claim 3, wherein said projection lens functions as a convex lens in a first direction perpendicular to the optical axis, and emits light diffused in a second direction perpendicular to both the optical axis and the first direction.

8. The lighting device according to claim 5, wherein said projection lens refracts the light in the second direction so that an angle of emission of the emitted light has a predetermined ratio to an angle of incidence of the light originating from the second focal position.

9. The lighting device according to claim 6, wherein said projection lens refracts the light in the second direction so that an angle of emission of the emitted light has a predetermined ratio to an angle of incidence of the light originating from the second focal position.

11. The lighting device according to claim 2, wherein said light source is a light emitting device.

12. The lighting device according to claim 3, wherein said light source is a light emitting device.

16. The lighting device according to claim 11, wherein said light source is a light emitting diode.

17. The lighting device according to claim 12, wherein said light source is a light emitting diode.

20. The lighting device according to claim 2, wherein said reflecting member has a mounting part configured to fix and hold said projection lens.

21. The lighting device according to claim 2, wherein the reflecting surface is an elliptic reflecting surface.