Optical element for an emitting unit of an optical acquisition device, emitting unit, optical acquisition device, motor vehicle, and method

Patent metadata

Field	Value
Publication number	US-10859706-B2
Application number	US-201816489102-A
Country	US
Kind code	B2
Filing date	Jan 4, 2018
Priority date	Feb 28, 2017
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

The invention relates to an optical element ( 13 ) for an emitting unit ( 8 ) of an optical acquisition device ( 3 ), wherein the optical element ( 13 ) comprises a first side ( 13 a ) having a reflective first free-form surface (F 1 ) and a second side ( 13 b ), which is opposite to the first side ( 13 a ), having a refractive second free-form surface (F 2 ). Furthermore, the optical element ( 13 ) is designed to transmit a beam bundle ( 10 ) incident on the second side ( 13 b ) on the optical element ( 13 ) at least in large part through the second free-form surface (F 2 ) up to the first free-form surface (F 1 ), to reflect the beam bundle ( 10 ) transmitted through the second free-form surface (F 2 ) up to the first free-form surface (F 1 ) at the first free-form surface (F 1 ), and to emit the beam bundle ( 10 ) reflected from the first free-form surface (F 1 ) via the second free-form surface (F 2 ). In this case, the first free-form surface (F 1 ) is designed to increase a divergence of the beam bundle ( 10 ) incident on the first free-form surface (F 1 ), and the second free-form surface (F 2 ) is designed, upon emission of the beam bundle ( 10 ) reflected from the first free-form surface (F 1 ), to reduce the divergence increased during the reflection.

First claim

The invention claimed is:

1. An optical element for an emitting unit of an optical acquisition device, the optical element comprising:
a first side having a reflective first free-form surface; and
a second side, which is opposite to the first side, having a refractive second free-form surface,
wherein the optical element is configured to:
transmit a beam bundle incident on the second side on the optical element at least in large part through the second free-form surface up to the first free-form surface,
reflect the beam bundle transmitted through the second free-form surface up to the first free-form surface at the first free-form surface, and
emit the beam bundle reflected from the first free-form surface via the second free-form surface,

wherein the first free-form surface is configured to increase a divergence of the beam bundle incident on the first free-form surface, and the second free-form surface is configured to reduce the divergence increased during the reflection upon emission of the beam bundle reflected from the first free-form surface,
wherein the optical element is a free-form lens having a reflective coating on one side of the free-form lens to provide the first reflective free-form surface of the optical element, and
wherein the reflective coating comprises a metallic material selected from the group consisting of: gold, silver, aluminium, and copper.

2. The optical element according to claim 1 , wherein the optical element is configured to image a first light distribution that is incident over multiple time steps on the second free-form surface of the optical element in at least one incidence direction,
the first light distribution is incident in its entirety over the multiple time steps, and in a first plane perpendicular to the at least one incidence direction on the optical element,
the first light distribution is delimited by two nonparallel first straight lines,
the optical element images the first light distribution on an emitted light distribution providing a field of view emitted from the optical element, and
the emitted light distribution is delimited in a second plane perpendicular to at least one determined emission direction by two parallel second straight lines.

3. The optical element according to claim 1 , wherein the optical element is configured, upon emission of the beam bundle reflected from the first free-form surface, to reduce the divergence of the beam bundle increased during the reflection in such a manner that the emitted beam bundle has a divergence less than 0.2°.

4. The optical element according to claim 1 , wherein the free-form lens comprises a glass and/or a plastic.

5. An emitting unit for an optical acquisition device of a motor vehicle, the emitting unit comprising an optical element according to claim 1 .

6. The emitting unit according to claim 1 , wherein the emitting unit comprises a light source for providing at least one beam bundle and a deflection unit configured to deflect the at least one beam bundle in successive time steps in different predetermined incidence directions and radiate the at least one beam bundle onto the second free-form surface of the optical element, wherein a respective incidence direction corresponds to a respective emission direction, in which the beam bundle incident on the second free-form surface of the optical element is emitted from the second free-form surface of the optical element after reflection at the first free-form surface of the optical element.

7. The emitting unit according to claim 5 , wherein the deflection unit comprises a mirror having a mirror plane, wherein the emitting unit is configured so that the at least one beam bundle provided by a light source is incident on the mirror plane in a main incidence direction, wherein the mirror is arranged in such a manner that the mirror plane is inclined in relation to the main incidence direction by a fixed first angle around a first axis perpendicular to the main incidence direction and is pivotable by various predetermined second angles around a second axis perpendicular to the first axis, wherein the first and the second axis extend in the mirror plane.

8. The emitting unit according to claim 7 , wherein an incidence direction range is associated with a respective second angle, wherein the incidence directions of a first of the incidence direction ranges differ from the incidence directions of a second of the incidence direction ranges, which is different from the first, in a third angle, which is twice as large as the difference between the second angles associated with the first and second incidence direction ranges.

9. The emitting unit according to claim 7 , wherein the emitting unit is configured in such a manner that the optical element is irradiated for a respective set second angle of the mirror using a light distribution, which has a maximum extension in a respective first direction which defines a length which is multiple times greater than a width of the light distribution perpendicular to the length.

10. The emitting unit according to claim 9 , wherein the respective first directions for a respective set second angle enclose a fourth angle with one another which is not equal to zero.

11. The emitting unit according to claim 7 , wherein
the optical element images a first light distribution incident on the optical element for a respective set second angle of the mirror
the optical element images the first light distribution on an emitted light distribution that is respective to the first light distribution,
the respective emitted light distribution has a maximum extension in a respective second direction which defines a length of the respective emitted light distribution,
the length is multiple times greater than a width of the respective emitted light distribution that is perpendicular to the length, and
the second directions are each parallel to one another.

12. A motor vehicle comprising an optical acquisition device having an emitting unit according to claim 1 .

13. A method for producing an optical element according to claim 1 , the method comprising:
pouring a molten material into an injection mould comprising a cavity, the cavity comprising a first side having a first predetermined free-form surface, which corresponds to the first free-form surface of the optical element and a second side having a second predetermined free-form surface, which corresponds to the second free-form surface of the optical element,
wherein the first side of the cavity is opposite to the second side of the cavity at least in the state of the injection mould filled with the material;
transferring the molten material into solid state, wherein the material is transparent at least in the solid state;
coating the molten material, which is removed from the injection mould and forms a free-form lens, on a predetermined free-form surface of the material formed by the first side of the cavity, using a reflective coating.

Assignees

• Valeo Schalter & Sensoren Gmbh

Inventors

• Nguyen Ho Hoai Duc
• Horvath Peter

Classifications

• G02B27/0025

  for optical correction, e.g. distorsion, aberration · CPC title

• G02B17/0856

  comprising a refractive element with a reflective surface, the reflection taking place inside the element, e.g. Mangin mirrors · CPC title

• G02B26/10 Primary

  Scanning systems · CPC title

• G01S7/4814

  of transmitters alone · CPC title

• G01S7/4817

  relating to scanning · CPC title