DARKENING DEVICE FOR AN ADAS-CAMERA, CONTROL UNIT FOR AN ADAS-CAMERA-SYSTEM, ADAS-CAMERA-SYSTEM AND VEHICLE CONTAINING AN ADAS-CAMERA-SYSTEM

Abstract

This disclosure relates to a dimming element for an ADAS camera comprising a layer that can be placed on a surface of a window that comprises liquid crystal cells that can be actuated individually and absorb light when electricity is applied, in order to dim an image section of the ADAS camera depending on the position of the sun detected by the ADAS camera. A delay layer, located between the layer and the ADAS camera may provide polarized light to the ADAS camera independently of an alignment of the liquid crystal cells in relation to the ADAS camera. The disclosure also relates to a control device for an ADAS camera system, and ADAS camera system, and a vehicle comprising an ADAS camera system.

Claims

1. A dimming element for an advanced driver-assistance system (ADAS) camera, wherein a surface area of the dimming element is a same size as a field of vision of the ADAS camera on an inner surface of at least one of a windshield or rear window of a vehicle, the dimming element comprising: a layer configured to be placed on the inner surface, the layer comprising liquid crystal cells, wherein the liquid crystal cells can be actuated individually, and absorb light when electricity is applied, and configured to dim an image section of the ADAS camera, depending on a position of the sun as detected by the ADAS camera; and a delay layer, located between the layer and the ADAS camera, configured to provide light to the ADAS camera independently of an orientation of the liquid crystal cells in relation to the ADAS camera.

2. The dimming element according to claim 1, wherein the delay layer is located on a side of the layer facing away from the inner surface.

3. The dimming element according to claim 1, wherein the delay layer is a /4 delay layer.

4. The dimming element according to claim 1, wherein the dimming element is placed on the inner surface such that the dimming element is functionally connected to a defroster.

5. The dimming element according to claim 1, wherein the liquid crystals of the liquid crystal cells comprise an organic compound.

6. An advanced driver-assistance system (ADAS) camera system comprising: an ADAS camera; and a dimming element, comprising: a layer comprising liquid crystal cells, the liquid crystal cells configured to be actuated individually, to absorb light when electricity is applied, and to dim an image section of the ADAS camera; a delay layer located between the layer and the ADAS camera, the delay layer configured to provide light to the ADAS camera independently of an orientation of the liquid crystal cells in relation to the ADAS camera; a first interface for obtaining a position of the sun on an image sensor of the ADAS camera; a computing unit configured to determine which liquid crystal cells of the dimming element to dim by applying electricity to the liquid crystal cells at the position of the sun on the image sensor, depending on the position of the sun on the image sensor and depending on extrinsic and intrinsic parameters of the ADAS camera; and a second interface for applying electricity to the liquid crystal cells determined by the computing unit.

7. The ADAS camera system according to claim 6, further comprising: wherein the first control device is configured to actuate a first portion of the liquid crystal cells, and the second control device is configured to actuate a second portion of the liquid crystal cells, independently of the first control device.

8. The ADAS camera system according to claim 7, wherein the dimming element is located on the ADAS camera.

9. A vehicle comprising the ADAS camera system according to claim 7, wherein the ADAS camera is located on a rear view mirror of the vehicle, the dimming element is located on an inner surface of a windshield of the vehicle in a field of vision of the ADAS camera, and the first and second control devices are integrated in at least one of the ADAS camera or the dimming element.

10. The dimming element according to claim 1, wherein the dimming element comprises a heating element for heating the liquid crystals.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present disclosure shall be explained by way of example in the following exemplary embodiments and figures.

[0038] FIG. 1 shows an exemplary embodiment of a vehicle according to the present disclosure;

[0039] FIG. 2 shows an exemplary embodiment of a dimming element according to the present disclosure;

[0040] FIG. 3 shows an exemplary embodiment of an ADAS camera system according to the present disclosure; and

[0041] FIG. 4 shows an exemplary embodiment of a liquid crystal cell.

DETAILED DESCRIPTION

[0042] Identical reference symbols in the figures indicate identical or at least similar components. For purposes of clarity, only the reference symbols relevant to the respective figure are given in the individual figures.

[0043] FIG. 1 shows a vehicle 1. The vehicle 1 may be a passenger car. The subject matter of the present disclosure can also be used analogously with other land vehicles, e.g., trucks and/or rail vehicles, air vehicles, and/or water vehicles. The vehicle 1 comprises a windshield 2a and a rear window 2b. The windshield 2a and/or the rear window 2b may comprise a window defroster 4. FIG. 1 only shows the defroster 4 for the windshield 2a. The vehicle 1 comprises an interior 6. Passengers can be accommodated in the interior 6. There is a rear view mirror 5 in the interior 6. The vehicle driver is able to observe traffic behind the vehicle through the rear window 2b by means of the rear view mirror 5.

[0044] An ADAS camera 31 may be located on the rear view mirror 5, which has a field of vision directed toward the windshield 2a. The ADAS camera 31 may be a mono-camera with just one lens, or a tri-camera with three lenses of different focal lengths and/or apertures, for example. There may be a dimming element 10 on an inner surface 3 of the windshield 2a. The dimming element 10 may be located in the field of vision of the ADAS camera 31, on the inner surface, and may be the same size as the field of vision where it intersects with the windshield. The dimming element 10 may be located on the inner surface 3 of the windshield 2a such that it is flush with the plane thereof. The sun S shines through the windshield 2a onto the ADAS camera 31. Without the dimming element 10 according to the present disclosure, the sun would cause a strong glare in the ADAS camera 31, in particular on an image sensor 32 of the ADAS camera 31, and/or there would be light beams or internal reflections in the region of the diffused light shade and/or in a lens of the ADAS camera 31. These problems caused by the sun S are avoided through selective actuation of individual liquid crystal cells 12 of the dimming element 10.

[0045] FIG. 2 shows the dimming element 10 applied to the inner surface 3 of the windshield 2a. The dimming element 10 may be in the shape of a trapezoid. The liquid crystal cells 12 may be arranged in rows and columns in a matrix. Through actuation of the dimming element 10 according to the present disclosure, those liquid crystal cells 12 that result in a dimming of the region the size of the sun S in the image are supplied with electricity such that they absorb light. In FIG. 2, a current position of the sun S overlaps four liquid crystal cells 12. These four liquid crystal cells 12 are therefore actuated, and thus dimmed.

[0046] Depending on the position of the sun S, or the size of the sun S in the image, more or fewer liquid crystal cells 12 are actuated in order to block out the sun. As the sun S moves across the dimming element 10, e.g., when cornering the vehicle 1, the dimming element 10 is actuated such that the liquid crystal cells 12 that are dimmed changes in accordance with the sun S, such that the sun S is dimmed throughout the cornering.

[0047] FIG. 3 shows an ADAS camera system 30. The ADAS camera system 30 comprises the ADAS camera 31 and the dimming element 10 according to the present disclosure. The dimming element 10 may comprise a separate heating element 14 with which the dimming element 10 may lie on the inner surface 3 of the windshield 2a. A delay layer 13 may be located between the inner surface 3 of the windshield 2a and the ADAS camera 31. The liquid crystal cells 12 may be located between the heating element 14 and the delay layer 13. The liquid crystal cells 12 may form a layer 11 with the heating element 14 on which the delay layer 13 is located. The liquid crystal cells 12 of the layer 11 may be actuated with a control device 20, i.e., they are supplied in a modulated manner with electricity, such that they are activated and deactivated.

[0048] A first control device 20a may control the liquid crystal cells 12 indicated by the letter a. A second control device 20b may control the liquid crystal cells 12 indicated by the letter b. If the first control device 20a malfunctions, the liquid crystal cells a remain transparent. The liquid crystal cells b can still be activated and deactivated with the other control device 20b, and thus dimmed. The same applies if the second control device 20b malfunctions. The first control device 20a and second control device 20b are advantageously located in a space-saving manner inside a housing for the ADAS camera 31.

[0049] The control devices 20, 20a, 20b comprise a first interface 21 to the image sensor 32 of the ADAS camera 31. A computing unit 22 of the control device 20, 20a, 20b obtains a position of the sun S on the image sensor 32 of the ADAS camera via the first interface 21, e.g., in the form of data, regarding which pixels of the image sensor 32 image the sun S. The computing unit 22 determines which of the liquid crystal cells 12 of the dimming element 10 are to be dimmed by applying electricity to where the sun S is located on the image sensor 32, depending on the position of the sun S on the image sensor 32 and depending on extrinsic and intrinsic parameters of the ADAS camera 31. The control devices 20, 20a, 20b may also comprise a second interface 23 to the liquid crystal cells 12. Electricity can be applied by means of the second interface 23 to those liquid crystal cells 12 determined by the computing unit 22.

[0050] FIG. 4 shows a liquid crystal cell 12 without electricity applied to it. The liquid crystal 15 may be located between a first plate 16 and a second plate 17. The liquid crystal 15 can have a helical arrangement of rod-shaped molecules, for example, that is perpendicular to first plate 16 and second plate 17. The first plate 16 and second plate 17 align the molecules of the liquid crystal 15 through the structure of their surfaces facing the liquid crystal 15. As a result of this alignment, the molecules of the liquid crystal are oriented parallel to the surface of the respective plate 16, 17 in a specific direction. The liquid crystal cells 12 are located between a polarizer 18 and an analyzer 19. When electricity is applied, an electrical field is generated perpendicular to the plates 16, 17, and molecules of the liquid crystal become aligned in the direction of the field, until they are parallel to the field vector as the voltage increases. At this point, the helical structure disappears.

REFERENCE SYMBOLS

[0051] 1 vehicle [0052] 2a windshield [0053] 2b rear window [0054] 3 inner surface [0055] 4 window defroster [0056] 5 rear view mirror [0057] 6 interior space [0058] 10 dimming element [0059] 11 layer [0060] 12 liquid crystal cells [0061] 13 delay layer [0062] 14 heating element [0063] 15 liquid crystal [0064] 16 first plate [0065] 17 second plate [0066] 18 polarizer [0067] 19 analyzer [0068] 20 control device [0069] 20a first control device [0070] 20b second control device [0071] 21 first interface [0072] 22 computing unit [0073] 23 second interface [0074] 30 ADAS camera system [0075] 31 ADAS camera [0076] 32 image sensor [0077] S sun [0078] a liquid crystal cell [0079] b liquid crystal cell