Lighting and/or signalling system comprising telemetry means

Patent metadata

Field	Value
Publication number	US-10488522-B2
Application number	US-201515521094-A
Country	US
Kind code	B2
Filing date	Oct 23, 2015
Priority date	Oct 24, 2014
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

The present invention relates to a lighting system including a primary light source producing a primary light beam in the direction of a conversion device that returns a secondary light radiation to an optical imaging system forming a projected light beam. A light sensor generates a signal corresponding to the light received by this sensor. The light includes a non-converted light part of the first primary light beam which is returned by the conversion device in the projected light beam and is reflected by an obstacle situated in the zone illustrated by said projected light beam. A control unit has modulation means generating a modulation signal for the primary light, and demodulation means for processing the signal formed by said sensor, and determines a distance between the obstacle and the lighting system.

First claim

The invention claimed is:

1. A lighting and/or signaling system, especially for a motor vehicle, comprising:
a first primary light source producing a first primary light beam (L 1 ) of given wavelength,
a first wavelength conversion device receiving the first primary light beam (L 1 ) and returning a secondary light radiation (B),
an optical imaging system receiving the secondary light radiation (B) returned by the conversion device and forming a projected light beam (FL) in the direction of a zone to be lit, the light beam comprising:
a first light sensor generating a signal corresponding to the light (L 11 R) received by this sensor, which light comprises a non-converted light part (L 11 ) of the first primary light beam (L 1 ) which is returned by the conversion device in the projected light beam (FL) and which is reflected by an obstacle (R) situated in the zone lit by said projected light beam (FL),

a control unit comprising:
first modulation means for generating a modulation signal for the first primary light (L 1 ),
first demodulation means for processing the signal formed by said first light sensor, and determining a first distance (d 1 ) between said obstacle (R) and the lighting system.

2. The lighting system according to claim 1 , further comprising a first filter placed at an entrance of the first light sensor, capable of letting through only light of wavelength identical or close to the wavelength of the primary light (L 1 ) emitted by the first primary light source.

3. The lighting system according to claim 1 , wherein the wavelength of the first primary light (L 1 ) emitted by the first primary light source is less than 500 nm, and preferably between 400 nm and 470 nm.

4. The lighting system according to claim 1 , wherein the projected light beam (FL) coming from the optical imaging system is white in color.

5. The lighting system according to claim 1 , wherein the first modulation means of the first primary light (L 1 ) are provided to generate a sinusoidal signal modulated at very high frequency, and to superimpose this signal on a carrier signal, with frequency content limited to lower frequencies.

6. The lighting system according to claim 5 , wherein the frequency of the modulated sinusoidal signal is higher than 1 GHz.

7. The lighting system according to claim 5 , wherein the modulated sinusoidal signal is affected by a phase modulation varying in the form of periodic ramps, preferably linear ones, whose frequency lies between 10 MHz and 100 MHz.

8. The lighting system according to claim 5 , wherein the first demodulation means comprise:
a nonlinear mixer to combine the modulation signal of the primary light (L 1 ) with the signal generated by the light sensor,
a low pass filter to eliminate the high frequencies of the signal coming from the nonlinear mixer so that the output signal of the low pass filter has a frequency proportional to the first distance (d 1 ) between said obstacle (R) and the lighting system.

9. The lighting system according to claim 1 , wherein the first primary light source is a laser, and preferably a diode laser.

10. The lighting system according to claim 9 , further comprising:
scanning means receiving the first primary light beam (L 1 ) coming from the first primary light source and distributing said first primary light beam (L 1 ) over a surface of the conversion device by controlling the spatial position of said first primary light beam (L 1 ),
image processing means associated with the control unit, to create a three-dimensional image of the relief illuminated by the secondary light beam (FL) by associating the spatial position of the first primary light beam (L 1 ) with the first distance (d 1 ) measured for this position.

11. The lighting system as according to claim 10 , comprising:
a second primary light source producing a second primary light beam (L 2 ) of given wavelength, and directed toward the conversion device, so as to be integrated in the light beam (FL) coming from the optical imaging system,
a second light sensor, generating a signal corresponding to the light (L 2 R) received by this second light sensor, comprising a part of the light coming from the second primary light beam (L 2 ) returned by the conversion device in the projected light beam (FL) and which is reflected by an obstacle (R) situated in the zone illuminated by said projected light beam (FL),
a second modulation means integrated in the control unit to generate a modulation signal of the second primary light (L 2 ),
a second demodulation means, integrated in the control unit, to process the signal generated by the second light sensor, and to determine a second distance (d 2 ) between said obstacle (R) and the lighting system.

12. The lighting system according to claim 11 , wherein the second primary light beam (L 2 ) has a wavelength which is located in a spectrum not visible to the human eye, and which is adapted so as not to be transformed by the conversion device, so that the light beam (L 2 ) coming from the second primary light source is entirely reflected by the conversion device in the direction of the optical imaging system.

13. The lighting system according to claim 12 , wherein the wavelength of the second light beam (L 2 ) coming from the second primary light source is greater than 800 nm.

14. The lighting system according to claim 11 , wherein the second modulation means of the second primary light (L 2 ) is provided to generate a sinusoidal signal modulated at very high frequency, and to superimpose this signal on a carrier signal with frequency content limited to lower frequencies.

15. The lighting system according to claim 11 , comprising a mirror reflecting the light of a wavelength equal to the wavelength of the second light beam (L 2 ) coming from the second primary light source and transparent to light of different wavelengths, onto which are directed the light beams (L 1 , L 2 ) coming respectively from the first and the second primary light source in order to be returned to the conversion device via the scanning means.

16. The lighting system according to claim 15 , wherein the scanning means, the first and the second primary light source are controlled so that an image formed on the conversion device by the beam (L 1 ) coming from the first primary light source is strictly included in an image formed on this device by the beam (L 2 ) coming from the second primary light source.

17. A motor vehicle comprising at least one lighting and/or signaling system according to claim 1 .

18. The lighting system according to claim 2 , wherein the wavelength of the first primary light (L 1 ) emitted by the first primary light source is less than 500 nm, and preferably between 400 nm and 470 nm.

19. The lighting system according to claim 3 , wherein the projected light beam (FL) coming from the optical imaging system is white in color.

20. The lighting system according to claim 4 , wherein the first modulation means of the first primary light (L 1 ) are provided to generate a sinusoidal signal modulated at very high frequency, and to superimpose this signal on a carrier signal, with frequency content limited to lower frequencies.

Assignees

• Valeo Vision

Inventors

• Puente Jean-Claude
• Albou Pierre
• Godbillon Vincent

Classifications

• G01S17/32 Primary

  using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated · CPC title

• G01S17/931

  of land vehicles · CPC title

• F21S43/16

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

• F21S41/176

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

• F21S41/16

  Laser light sources · CPC title