Automotive vehicle equipment integrating a device for measuring distance of objects
Automotive vehicle equipment integrating a device for measuring distances of objects situated in the field of detection of the device, the device comprising: at least one light emitter configured to emit light rays according to an emission field, a light receiver disposed outside the emission field of the emitter and configured to receive light rays according to a reception field corresponding to the detection field of the device, a means for measuring the travel time of the light rays between the emitter and the receiver, the equipment comprising at least one element preventing the reflection of the light rays issuing from the light emitter on the exterior of the equipment.
1. A piece of equipment for an automotive vehicle, incorporating a device for measuring the distance of objects located in the detection field of the device, the device comprising:
at least one light emitter configured to emit light rays in an emission field;
a light receiver placed outside of the emission field of the emitter and configured to receive light rays from a reception field corresponding to the detection field of the device;
a means for measuring the journey time of the light rays between the emitter and the receiver; and
at least one element preventing the reflection of light rays issued from the light emitter from the exterior surfaces of the piece of equipment.
2. The piece of equipment as claimed in claim 1 , in which the at least one element preventing the reflection of light rays issued from the light emitter comprises a diaphragm placed in front of the light emitter so as to prevent the light rays issued from the light emitter from illuminating the surfaces of the piece of equipment.
3. The piece of measuring equipment as claimed in claim 2 , in which the diaphragm is a metal diaphragm.
4. The piece of equipment as claimed in claim 2 , in which the diaphragm has a thickness larger than or equal to 0.1 mm and smaller than or equal to 0.5 mm.
5. The piece of equipment as claimed in claim 2 , in which the aperture of the diaphragm has substantially the same shape as the light receiver.
6. The piece of equipment as claimed in claim 2 , in which the edges of the aperture of the diaphragm are beveled so as to limit the reflection of rays issued from the light emitter from said edges.
7. The piece of equipment as claimed in claim 1 , in which the light emitter is configured so as to emit light pulses.
8. The piece of equipment as claimed in claim 1 , in which the light emitter is a laser diode or an LED emitting in the infrared.
9. The piece of equipment as claimed in claim 2 , further comprising a plurality of light emitters and a diaphragm in front of each light emitter.
10. The piece of equipment as claimed in claim 1 , further comprising a lens in front of said at least one emitter.
11. The piece of equipment as claimed in claim 10 , further comprising at least one first diaphragm between the emitter and the lens and a second diaphragm on the other side of the lens.
12. The piece of equipment as claimed in claim 11 , in which the first diaphragm is made of metal and the second diaphragm is made of plastic covered with an absorbent material.
13. The piece of equipment as claimed in claim 1 , in which the at least one element preventing the reflection of light rays issued from the light emitter comprises an antireflection coating placed on at least one portion of the surfaces of the piece of equipment.
14. The piece of equipment as claimed in claim 13 , in which the antireflection coating is specifically adapted to prevent the reflection of light rays at the wavelengths of the light rays emitted by the at least one light emitter.
15. A device for measuring the distance of objects located in the field of detection of the device, the device comprising:
at least one light emitter configured to emit light rays in an emission field;
a light receiver placed outside of the emission field of the emitter and configured to receive light rays from a reception field corresponding to the detection field of the device;
a means for measuring the journey time of the light rays between the emitter and the receiver; and
at least one diaphragm placed in front of the light emitter limiting the emission field so that the only light rays issued from the light emitter illuminating the reception field of the light receiver are the rays directly issued from the emitter.
16. The device as claimed in claim 15 , in which the diaphragm and the emitter are configured so that all the light rays issued from the light emitter directly illuminate the reception cone of the light receiver.
17. The device as claimed in claim 15 , wherein the at least one light emitter emits light rays in an incoherent emission field.
18. The device as claimed in claim 15 , wherein the light receiver placed outside of the emission field of the emitter receives light rays from an incoherent reception field corresponding to the detection field of the device.
19. A method for an automotive vehicle, incorporating a device for measuring the distance of objects located in the detection field of the device comprising at least one light emitter, a light receiver, a means for measuring a journey time of light rays and at least one element that prevents reflection of light rays, said method comprising:
emitting light rays in an emission field by the emitter;
receiving light rays from a reception field corresponding to a detection field of the device by the light receiver;
measuring the journey time of the light rays between the emitter and the receiver by the means for measuring; and
preventing the reflection of light rays issued from the light emitter from exterior surfaces by the element that prevents reflection.