Method for controlling a motor vehicle headlight

Patent metadata

Field	Value
Publication number	US-10801689-B2
Application number	US-201616064252-A
Country	US
Kind code	B2
Filing date	Dec 19, 2016
Priority date	Dec 22, 2015
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

The invention relates to a method for controlling a motor vehicle headlight which at least comprises a laser diode ( 1 ) and a light conversion element ( 8 ) paired with the laser diode ( 1 ). Light conversion element ( 8 ) regions corresponding to different regions of the light image ( 11 ′) can be illuminated periodically and with a varying intensity by means of a light beam ( 2 ) of the laser diode ( 1 ), and the illumination intensity in the light conversion element ( 8 ) regions corresponding to the different regions of the light image ( 11 ′) is adjusted simultaneously by both the relative illumination duration of the different regions as well as different luminous intensities of the laser diode ( 1 ) in the light conversion element ( 8 ) regions corresponding to the different regions of the light image ( 11 ′). In regions in which the light beam ( 2 ) is moved with an angular speed below a defined value for the angular speed, the laser diode ( 1 ) is solely deactivated and activated, and different luminous intensities of the laser diode ( 1 ) are set when the angular speed is above a defined value. The motor vehicle headlight according to the invention has a computing unit ( 4 ) for carrying out the method according to the invention.

First claim

The invention claimed is:

1. A method for controlling a motor vehicle headlight, which comprises a laser diode and a light conversion element assigned to the laser diode, wherein light conversion element regions corresponding to different regions of a light image are configured to be illuminated periodically and with a varying intensity with a light beam of the laser diode, wherein an illumination intensity in the light conversion element regions corresponding to the different regions of the light image is configured to be adjusted simultaneously by both a relative illumination duration of the different regions as well as different luminous intensities of the laser diode in the light conversion element regions corresponding to the different regions of the light image, and wherein the relative illumination duration is achieved by pivoting the light beam at varying speeds via the light conversion element regions corresponding to the various areas of the light image, the method comprising: when the light beam is moved with an angular speed below a defined value of the angular speed, deactivating and activating the laser diode to a constant luminous intensity to adjust the relative illumination duration of the regions, and when the light beam is moved with an angular speed above the defined value of the angular speed, setting different luminous intensities of the laser diode to adjust the luminous intensity of the regions, wherein the defined value for the angular speed is between 4000°/sec and 8000°/sec to reduce the problems of electromagnetic shielding.

2. The method of claim 1 , wherein the light beam ( 2 ) of the laser diode ( 1 ) is guided onto the light conversion element ( 8 ) by a moveable deflection mirror ( 10 ).

3. The method of claim 2 , wherein the deflection mirror ( 10 ) is part of an MEMS micro-scanner.

4. The method of claim 2 , wherein the deflection mirror ( 10 ) is electromagnetically driven.

5. The method of claim 1 , wherein the light conversion element ( 8 ) is illuminated by the light beam ( 2 ) of the laser diode ( 1 ) along lines and/or columns.

6. The method of claim 5 , wherein the light beam ( 2 ) is moved back and forth along the lines and/or columns.

7. The method of claim 1 , wherein the laser diode ( 1 ) comprises at least three different luminous intensity settings.

8. The method of claim 7 , wherein the at least three different luminous intensity settings comprise 100%, 50%, and 0% of a maximum luminous intensity of the laser diode ( 1 ).

9. A vehicle headlight comprising:
at least one laser diode ( 1 ) that is configured to be adjusted with regard to a luminous intensity;
a light conversion element ( 8 ), wherein a laser beam ( 2 ) of the at least one laser diode ( 1 ) is configured to be guided onto the light conversion element ( 8 ) in a scanning manner in order to generate a light image ( 7 ) thereon, which is projected as a light image ( 11 ′) onto-a road via an imaging system ( 12 );
a deflection mirror ( 10 ) configured to be pivoted in at least one coordinate direction in accordance with defined control characteristics; and
a laser control system ( 3 ) and a computing unit ( 4 ) assigned thereto, wherein the computing unit ( 4 ) is configured to control the motor vehicle headlight according to claim 1 .

10. The method of claim 1 , wherein the defined value for the angular speed is between 5000°/sec and 7000°/sec.

11. The method of claim 1 , wherein the defined value for the angular speed is 6000°/sec.

Assignees

• Zkw Group Gmbh

Inventors

• Mitterlehner Thomas
• Koller Jan
• Weber Emanuel
• Schantl Patrik

Classifications

• F21S41/176

  Light sources where the light is generated by photoluminescent material spaced from a primary light generating element · CPC title

• F21S41/663 Primary

  by switching light sources (by switching incandescent light sources F21S41/162) · CPC title

• G02B26/0833

  the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD (G02B26/0825 takes precedence; micromechanical devices in general B81B) · CPC title

• F21S41/16

  Laser light sources · CPC title

• F21S41/675 Primary

  by moving reflectors · CPC title