Motor Vehicle Having a Projection Unit, and Method for Operating a Motor Vehicle

Abstract

A motor vehicle has a projection unit for projecting graphical or character-based information on a projection surface. The projection unit is connected to a monitoring circuit of the motor vehicle that is configured to project the graphical or character-based information. The monitoring circuit includes a brightness sensor for determining a value for the ambient brightness around the motor vehicle and a computer unit for controlling, on the basis of the value for the ambient brightness received from the brightness sensor, the size of the projection on the projection surface due to the projection unit.

Claims

1.-12. (canceled)

13. A motor vehicle comprising: a projection unit that is configured to project graphical or visual information onto a projection surface; and a monitoring circuit, wherein: the projection unit is connected to the monitoring circuit, and the monitoring circuit comprises a brightness sensor for determining a value of brightness in an environment of the motor vehicle and a computing unit for controlling a size of a projection on the projection surface by the projection unit based on the value of the brightness as received from the brightness sensor.

14. The motor vehicle according to claim 13, wherein the brightness sensor is a light sensor and/or a rain sensor for controlling running lights and/or a windscreen wiper of the motor vehicle.

15. The motor vehicle according to claim 13, wherein the brightness sensor is a camera, an image field of which camera records the projection surface.

16. The motor vehicle according to claim 13, wherein: the projection unit is a digital projection unit, and a size of the projection on the projection surface is variable by digital image information that contains the graphical or visual information and that is supplied to the projection unit as input information.

17. The motor vehicle according to claim 13, wherein an orientation of the projection unit relative to the projection surface is variable between at least two positions by an actuator in order to vary the size of the projection on the projection surface based on the value received from the brightness sensor.

18. The motor vehicle according to claim 17, wherein optics of the projection unit are tiltable between the at least two positions by the actuator.

19. The motor vehicle according to claim 13, wherein the monitoring circuit is configured, in an event of the value of the brightness being above a predefined threshold value, to project the graphical or visual information only in a subregion of a maximum possible theoretical area on the projection surface.

20. The motor vehicle according to claim 19, wherein the subregion is located in the region of the maximum possible theoretical area on the projection surface that is at a small distance from the projection unit.

21. The motor vehicle according to claim 13, wherein the monitoring circuit is configured, in an event of the value of the brightness being below a predefined threshold value, to project the graphical or visual information completely in a maximum possible theoretical area on the projection surface.

22. A method for operating a motor vehicle having a projection unit for projecting graphical or visual information onto a projection surface, wherein the projection unit is connected to a monitoring circuit of the motor vehicle, the method comprising: determining, by a brightness sensor of the monitoring circuit, a value of brightness in an environment of the motor vehicle, and controlling a size of the projection on the projection surface by the projection unit based on the value of the brightness as received from the brightness sensor.

23. The method according to claim 22, wherein, in an event of the value of the brightness being above a predefined threshold value, the graphical or visual information is projected only in a subregion of a maximum possible theoretical area on the projection surface.

24. The method according to claim 22, wherein, in an event of the value of the brightness being below a predefined threshold value, the graphical or visual information is projected completely in a maximum possible theoretical area on the projection surface.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1 shows a schematic illustration of a motor vehicle according to an exemplary embodiment of the invention in a plan view, wherein a projection on a projection surface, which projection is generated by a projection unit of the motor vehicle, is illustrated on a left-hand vehicle side by way of example.

[0024] FIG. 2 shows the motor vehicle shown in FIG. 1, reproducing the projection onto the projection surface when using a digital projection unit in first, dark ambient conditions.

[0025] FIG. 3 shows the motor vehicle shown in FIG. 2, reproducing the projection onto the projection surface when using the digital projection unit in second, comparatively bright ambient conditions.

[0026] FIG. 4 shows the motor vehicle shown in FIG. 1, reproducing the projection onto the projection surface when using a mechanically changeable projection unit in first, dark ambient conditions.

[0027] FIG. 5 shows the motor vehicle shown in FIG. 4, reproducing the projection onto the projection surface when using the mechanically changeable projection unit in second, comparatively bright ambient conditions.

DETAILED DESCRIPTION OF THE DRAWINGS

[0028] FIG. 1 shows a schematic illustration of a motor vehicle 10 according to an exemplary embodiment of the invention in a plan view. The motor vehicle 10 comprises a projection unit 12 and a monitoring circuit 20. The projection unit 12 is designed for example as a (digital) projector and/or comprises a microlens array. The monitoring circuit 20 comprises at least one brightness sensor 22 and a computing unit 24, wherein the computing unit 24 is connected both to the brightness sensor 22 and to the projection unit 12 in order to exchange data. The computing unit 24 may be a controller of the monitoring circuit 20 or a central controller of the motor vehicle 10.

[0029] The projection unit 12 is designed to project graphical or visual information onto a projection surface 14. In the present exemplary embodiment, the projection surface 14 is on the ground, on the left next to the motor vehicle 10. This is purely exemplary, and the projection surface 14 may also be on the right-hand side of the motor vehicle 10 or in front of or behind the motor vehicle and the like. The projection surface may also be a wall.

[0030] The graphical or visual information may be a manufacturer logo. The graphical or visual information may alternatively also be other information that is in particular temporally and/or spatially changeable. Depending on the information to be projected by the projection unit 12 onto the projection surface 14, the projection unit 12 may be arranged in a door sill, in an exterior mirror (illustrated here) of the motor vehicle 10 or another component of the motor vehicle 10.

[0031] The graphical or visual information, as illustrated in FIG. 1, is projected as standard onto the projection surface 14 such that the projection on the projection surface 14 has a size and/or takes up an area that is theoretically as large as possible on account of the installation situation and/or the technical design of the projection unit in the motor vehicle. This maximum possible theoretical area is identified with the reference sign 14T and a broken line.

[0032] The brightness sensor 22, which is for example a light sensor and/or rain sensor for controlling running lights and/or a windscreen wiper of the motor vehicle, is designed to determine a value of the brightness in the environment of the motor vehicle 10. The value of the brightness in the environment of the motor vehicle 10 as determined by the brightness sensor 22 is transferred to the computing unit 24 in order to control the projection unit 12.

[0033] The computing unit 24 is designed, from the value of the brightness of the environment, to control the size of the projection on the projection surface 14 on the basis of the value of the ambient brightness as received from the brightness sensor 22. The projection unit 12 then projects the graphical or visual information with the determined size onto the projection surface 14, specifically on the basis of the value of the ambient brightness as received from the brightness sensor 22.

[0034] This procedure is based on the observation that, on account of the installation situation of the projection unit 12 in the motor vehicle and/or on account of its light source and/or its optical system, the information from the projection on the projection surface 14 is at least partially able to be recognized only with difficulty depending on the ambient conditions. In FIG. 1, in a first subregion 16 of the projection surface 14 that is located closer to the projection unit 12, the information from the projection is thus able to be recognized well in bright ambient conditions, while in a second subregion 18 of the projection surface 14, which is further away from the projection unit 12, the information is more difficult to recognize or is even no longer able to be recognized at all in bright ambient conditions. This problem exists in particular in projection units that illuminate the projection surface 14 obliquely, such as for example in the case of the known light carpet, in which there is a large drop in brightness away from the projection unit 12, meaning that, in certain ambient conditions, only the brightest information, in the first subregion 16 of the projection surface 14, is visible (see the example in FIG. 1).

[0035] FIGS. 2 and 3 show a first exemplary embodiment as to how this problem is able to be countered in the case of a digital projection unit 12. In FIG. 2, the situation is illustrated here in first, dark ambient conditions, while FIG. 3 illustrates the situation in second, comparatively bright ambient conditions. The graphical or visual information from the projection is symbolized in each case by a hatched rectangle, wherein the projection may in practice of course also have other boundary shapes.

[0036] While the maximum possible theoretical area 14T on the projection surface 14 is utilized completely by the projection in dark ambient conditions, only a subregion, which may correspond for example to the first subregion 16 from FIG. 1, of the maximum possible theoretical area 14T on the projection surface 14 is used for the projection by the projection unit 12 in bright ambient conditions. In the case of a digital projection unit, the maximum possible theoretical projection area 14T may in this case be used to between 100% and a few percent of its potential degree of use depending on the ambient conditions. In this case, the graphical or visual information may be displayed with a reduced size by the projection, or only an excerpt of the complete graphical or visual information may be displayed.

[0037] FIGS. 4 and 5 show a further exemplary embodiment in which the projection unit 12 is pivoted or tilted between a first and at least one second position by the computing unit 24 depending on the value of the brightness in the environment as recorded by the brightness sensor 22. In this case, according to the exemplary embodiment illustrated in FIG. 4, in dark ambient conditions, the maximum possible theoretical area 14T on the projection surface 14 is utilized. In bright ambient conditions (FIG. 5), the projection unit 12 and/or its optical system are/is tilted, such that the maximum possible theoretical area 14T on the projection surface 14 amounts to only a portion of the maximum possible theoretical area 14T from FIG. 4. As a result of the tilting of the projection unit 12, the graphical or visual information is displayed completely here, but with a reduced size. Slight distortions may possibly occur here.

[0038] As an alternative to tilting, the projection unit 12 may be varied between the at least two positions by a lens movement and/or a change in the optics of the projection unit 12, such that a smaller or larger region of the optics of the projection unit 12 is illuminated.

[0039] The control performed by the computing unit 24 as to whether the maximum possible theoretical projection surface is utilized to the maximum extent (in dark conditions) or not (in comparatively brighter ambient conditions) may be regulated using threshold values. In the event of a recorded value of the ambient brightness that is above a predefined threshold value, the graphical or visual information may be projected only in a subregion of the maximum possible theoretical area 14T onto the projection surface 14. In this case, as has been explained above, the subregion that is at a smaller distance from the projection unit 12 is illuminated by the projection unit 12. By contrast, in the event of a recorded value of the ambient brightness that is below the predefined threshold value, the graphical or visual information is projected completely into the maximum possible theoretical area 14T on the projection surface 14.

[0040] It goes without saying that not just one threshold value but rather a plurality of threshold values could be defined, such that areas of different size up to the maximum possible theoretical area on the projection surface are utilized for the projection of the graphical or visual information. This determination is performed by the monitoring circuit 20, and in particular its computing unit 24.

LIST OF REFERENCE SIGNS

[0041] 10 motor vehicle [0042] 12 projection unit [0043] 14 projection surface [0044] 14T maximum possible theoretical area of the projection on the projection surface [0045] 14T maximum possible theoretical area of the projection on the projection surface [0046] 16 first (bright) subregion of the projection surface [0047] 18 second (dark) subregion of the projection surface [0048] 20 monitoring circuit [0049] 22 brightness sensor [0050] 24 computing unit