Illumination device for a motor vehicle

Patent metadata

Field	Value
Publication number	US-9752745-B2
Application number	US-201414505139-A
Country	US
Kind code	B2
Filing date	Oct 2, 2014
Priority date	Apr 3, 2012
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

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.

First claim

What is claimed is:

1. An illumination device for a motor vehicle, comprising:
a light source formed of a number of semiconductor diodes; and
a vector scanner arranged in a path of a light beam generated by light of the light source, the scanner having a control unit configured to control the vector scanner to generate a light spot at a distance from the illumination device and to form a predefined light distribution larger than the light spot at the distance from the illumination device by changing a position of the light beam during operation of the illumination device,
wherein the control unit is configured to be capable of controlling changing of vector scanner properties including a scanning speed at which the light spot is moved, a scanning path along which the light spot is moved, and a size of the light spot, and is configured to control at least one of the vector scanner properties to vary a local light intensity within the predetermined light distribution without varying an intensity of the light beam.

2. The illumination device according to claim 1 , wherein the control unit is configured to control the vector scanner to generate the predefined light distribution having the locally varied light intensity 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 the control unit control of the vector scanner by reducing the size of the light spot in regions having the higher light intensity using optics arranged in the illumination device downstream of the scanner.

4. The illumination device according to claim 1 , wherein the predefined light distribution with the locally varied light intensity is generated by the control unit control of the sector scanner by reducing the size of the light spot in regions having the higher light intensity using optics arranged in the illumination device downstream of the scanner.

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 controlled by the control unit 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 output of the semiconductor diodes.

8. The illumination device according to claim 1 , wherein the optics comprise a lens and/or a reflector having a variable focal distance.

9. 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.

10. The illumination device according to claim 9 , 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.

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

12. The illumination device according to claim 11 , wherein the headlight is configured to generate a low-beam light characteristic and/or a high-beam light characteristic as the predefined light distribution.

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

14. 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.

15. The illumination device according to claim 14 , wherein the beam limitation device comprises an aperture and/or an optical fiber.

16. A motor vehicle, comprising:
one or more illumination devices, each illumination device comprising:
a light source formed of a number of semiconductor diodes; and
a vector scanner arranged in a path of a light beam generated by light of the light source, the scanner having control unit configured to control the vector scanner to generate a light spot at a distance from the illumination device and to form a predefined light distribution at the distance from the illumination device larger than the light spot by changing a position of the light beam during operation of the illumination device
wherein
the control unit is configured to be capable of controlling changing of vector scanner properties including a scanning speed at which the light spot is moved, a scanning path along which the light spot is moved, and a size of the light spot, and is configured to control at least one of the vector scanner properties to vary a local light intensity within the predetermined light distribution without varying an intensity of the light beam.

17. A method of operating an illumination device comprising a light source formed of a number of semiconductor diodes and a vector scanner having a control unit configured to control operation of the vector scanner in a manner 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, using the control unit to control the vector scanner to move a light spot generated by the light beam at a distance from the illumination apparatus to produce a predefined light distribution larger than the light spot at the distance from the illumination device; and
varying a local light intensity within the predetermined light distribution without varying an intensity of the light beam using the control unit, the control unit being configured to be capable of controlling changing of vector scanner properties including a scanning speed of the vector scanner by which the light spot is moved, a scanning path produced by the vector scanner along which the light spot is moved, and a size of the light spot and configured to vary at least one of the vector properties to vary the local light intensity.

18. The method according to claim 17 , wherein the varying act further comprises the act of:
reducing, using the control unit of the vector scanner, 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.

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Erdl Helmut
• Hanafi Abdelmalek

Classifications

• F21S41/147

  the main emission direction of the LED being angled to the optical axis of the illuminating device · CPC title

• F21S41/675

  by moving reflectors · CPC title

• F21S41/645

  by electro-optic means, e.g. liquid crystal or electrochromic devices · CPC title

• G02B19/0014

  at least one surface having optical power · CPC title

• G02B26/101

  with both horizontal and vertical deflecting means, e.g. raster or XY scanners (colour television using laser beams scanning a display screen H04N9/3129) · CPC title