Illumination Device for a Motor Vehicle

• US 20150016135A1
• Filed: 10/02/2014
• Published: 01/15/2015
• Est. Priority Date: 04/03/2012
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: ERDL, Helmut, HANAFI, Abdelmalek
• Granted Patent: US 9,752,745 B2
• Time in Patent Office: Days
• US Class Current: 362/510
• 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 41/16 Laser light sources
• CPC Class Codes: F21S 41/176 Light sources where the light is generated by photoluminescent material spaced from a primary light generating element
• CPC Class Codes: F21S 41/25 Projection lenses
• CPC Class Codes: F21S 41/635 by moving refractors, filters or transparent cover plates
• CPC Class Codes: F21S 41/645 by electro-optic means, e.g. liquid crystal or electrochromic devices
• CPC Class Codes: F21S 41/675 by moving reflectors
• CPC Class Codes: G02B 19/0014 at least one surface having optical power
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00
• CPC Class Codes: G02B 26/101 with both horizontal and vertical deflecting means, e.g. raster or XY scanners colour television using laser beams scanning a display screen H04N9/3129

Abstract

An illumination device for a motor vehicle includes a light source consisting of a number of semiconductor diodes, and a scanner onto which a light beam obtained from light of the light source falls and which modifies the position of the light beam during operation of the illumination device and thereby moves a light spot produced by the light beam at a distance from the illumination device. The moved light spot allows a predetermined light distribution to be generated. The illumination device is designed such that the scanning speed at which the light spot is moved, the scanning path along which the light spot is moved, and/or the size of the light spot can be varied and is/are controlled to generate the predetermined light distribution.

Claims

1. An illumination device for a motor vehicle, comprising:

a light source formed of a number of semiconductor diodes;

a scanner arranged in a path of a light beam generated by light of the light source, the scanner changing a position of the light beam during operation of the illumination device to move a light spot generated by the light beam at a distance from the illumination device, wherein movement of the light spot generates a predefined light distribution, and

wherein a scanning speed at which the light spot is moved, a scanning path along which the light spot is moved, and/or a size of the light spot is variably controlled to generate the predefined light distribution.

2. The illumination device according to claim 1, wherein a predefined light distribution having a locally varied light intensity is generated by reducing the scanning speed in regions of the predefined light distribution having a higher light intensity and/or passing the light spot more frequently by the regions with the higher light intensity according to the scanning path.

3. The illumination device according to claim 2, wherein the predefined light distribution with the locally varied light intensity is generated by reducing the size of the light spot in regions having the higher light intensity.

4. The illumination device according to claim 1, wherein the predefined light distribution with the locally varied light intensity is generated by reducing the size of the light spot in regions having the higher light intensity.

5. The illumination device according to claim 1, wherein the number of semiconductor diodes comprises one or more laser diodes.

6. The illumination device according to claim 1, wherein the number of semiconductor diodes are operated at a constant power when generating the predefined light distribution.

7. The illumination device according to claim 6, wherein the constant power is a maximum power of the semiconductor diodes.

8. The illumination device according to claim 1, wherein the scanner is a vector scanner configured to vary the scanning speed and/or the scanning path.

9. The illumination device according to claim 1, further comprising:

optics arranged in the illumination device downstream of the scanner, the optics being configured to vary the size of the light spot.

10. The illumination device according to claim 9, wherein the optics comprise a lens and/or a reflector having a variable focal distance.

11. The illumination device according to claim 1, wherein the light source generates monochromatic light, and further comprising a conversion element operable to convert the monochromatic light of the light source into white light.

12. The illumination device according to claim 11, wherein the conversion element is arranged:

(i) on the light source, (ii) between the light source and the scanner, or (iii) downstream of the scanner.

13. The illumination device according to claim 1, wherein the illumination device comprises a headlight.

14. The illumination device according to claim 1, wherein the illumination device comprises a signal lamp.

15. The illumination device according to claim 13, wherein the headlight is configured to generate a low-beam light characteristic and/or a high-beam light characteristic as the predefined light distribution.

16. The illumination device according to claim 1, further comprising:

a beam limitation device arranged between the light source and the scanner, the beam limitation device being configured to limit a cross-section of the light beam along a predefined cut-off line, wherein

one or more cut-off lines are formed in the predefined light distribution with at least one section of the predefined cut-off line.

17. The illumination device according to claim 16, wherein the beam limitation device comprises an aperture and/or an optical fiber.

18. A motor vehicle, comprising:

one or more illumination devices, each illumination device comprising;

a light source formed of a number of semiconductor diodes;

a scanner arranged in a path of a light beam generated by light of the light source, the scanner changing a position of the light beam during operation of the illumination device to move a light spot generated by the light beam at a distance from the illumination device, wherein movement of the light spot generates a predefined light distribution, and

wherein a scanning speed at which the light spot is moved, a scanning path along which the light spot is moved, and/or a size of the light spot is variably controlled to generate the predefined light distribution.

19. A method of operating an illumination device comprising a light source formed of a number of semiconductor diodes and a scanner that changes a position of a light beam generated by light of the light source, the method comprising the acts of:

during operation of the illumination device, moving a light spot generated by the light beam at a distance from the illumination apparatus to produce a predefined light distribution; and

varying at least one of a scanning speed of the scanner by which the light spot is moved, a scanning path produced by the scanner along which the light spot is moved, or a size of the light spot, in order to generate the predefined light distribution.

20. The method according to claim 19, wherein the varying act further comprises the act of:

reducing the scanning speed in regions of the predefined light distribution that are to have a higher light intensity or controlling the scanning path to pass the light spot more frequently by the regions that are to have the higher light intensity.