Illumination apparatus for a motor vehicle

Abstract

The invention relates to an illumination apparatus for a motor vehicle, comprising a projection device (1) with an image generator (2), which is designed to generate an image (B) from the light of a lighting means (202), and comprising a projection optical unit (3) which is designed to generate a light distribution (LV) on a projection surface (PF) by projecting the image (B) generated by the image generator (2) onto the projection surface (PF). The illumination apparatus according to the invention is characterised in that the image generator (2) is enclosed by a first housing (201) and the projection optical unit (3) is enclosed by a second housing (301), wherein the first housing (201) and the second housing (301) are separate housings and the second housing (301) is exchangeably attached to the first housing (201).

Description

[0001] Lighting device for a motor vehicle

[0002] The invention relates to a lighting device for a motor vehicle.

[0003] It is known from the prior art to use motor vehicle lighting devices in the form of projectors. These projectors generate a corresponding light distribution in the interior or exterior of the motor vehicle through projection.

[0004] US 2010 / 0253919 A1 discloses a projector for a motor vehicle that generates a light distribution using a laser module and a lens. The projector can be installed, for example, in the rearview mirror or in a side door of the motor vehicle.

[0005] Document DE 21 2019 000 287 U1 describes a projector that can be installed under a vehicle door or under mirrors. The projector comprises a cylindrical inner housing arranged in a casing, wherein, among other things, at least one replaceable convex cassette top lens is provided in the inner housing.

[0006] Although projection lenses can be replaced in conventional automotive projectors, disassembling the projection lens to be replaced and assembling the replaced projection lens is very complex.

[0007] The object of the invention is to provide a lighting device for a motor vehicle with a projection device whose projection optics can be easily replaced.

[0008] This object is achieved by the lighting device according to claim 1. Further developments of the invention are defined in the dependent claims.

[0009] The lighting device according to the invention is intended for a motor vehicle, wherein the motor vehicle is preferably a passenger car, but can also be a truck if necessary. Where interactions between the lighting device and parts or components of the motor vehicle are described here and below, this is always to be understood as meaning that the interaction occurs when the lighting device is installed in the motor vehicle as intended. The lighting device according to the invention comprises a projection device. This projection device contains an image generator configured to generate an image from the light of a light source, which is a component of the image generator.In addition, the projection device contains a projection optics which is designed to generate a light distribution on a projection surface by projecting or projecting the image generated by the image generator onto the projection surface.

[0010] The lighting device according to the invention is characterized in that the image generator is enclosed by a first housing and the projection optics are enclosed by a second housing, wherein the first housing and the second housing are separate housings and the second housing is arranged on the first housing in a replaceable manner. In other words, the lighting device contains a modularly constructed projection device comprising a first module, which represents an image generator in a first housing, and a second module, which represents projection optics in a second housing. The second module (i.e., the second housing) can be replaced by being replaceably attached to the first module (i.e., the first housing).As a result, the light distribution generated by the lighting device according to the invention can be easily adapted to corresponding conditions inside or outside the motor vehicle by exchanging the projection optics.

[0011] In a particularly preferred variant of the lighting device according to the invention, the second housing can be removed from and reattached to the first housing without the need for tools. This makes replacing the projection optics particularly easy, since the person replacing the projection optics does not require any tools.

[0012] Depending on the embodiment, the attachment of the second housing to the first housing can be configured differently. For example, the second housing can be screwed to the first housing. Likewise, the second housing can be attached to the first housing via a known bayonet lock. In a particularly preferred embodiment, the second housing is slid onto the first housing via a guide.

[0013] In a further preferred variant, the second housing can be fixed to the first housing in various fixing positions, with the optical axis of the projection optics being positioned differently in the various fixing positions. In this way, a different light field and thus a different light distribution can be generated with the same projection optics by setting different fixing positions.

[0014] In a preferred variant of the embodiment just described, the optical axis is shifted parallel in the different fixation positions. In other words, changing the fixation position results in a parallel shift of the optical axis of the projection optics. This allows the symmetry of the light field generated by the projection optics to be easily changed. In particular, an asymmetric light cone can be generated from a symmetrical light cone by shifting the optical axis.

[0015] In a further preferred embodiment, one or more spacer elements are arranged on the above-described guide, onto which the second housing is pushed, by means of which the fixing position is adjusted. By changing the number of spacer elements or by changing their size, the fixing position can be easily and appropriately determined.

[0016] In a further, particularly preferred embodiment, the image generator used in the projection device is a digital image generator that generates the image based on digital image information. This allows the generated image, and thus the content of the light projection, to be easily modified by changing the digital image information.

[0017] Any image generator known from the prior art can be used as the digital image generator. In particular, the image generator can comprise at least one LCD display and / or at least one LCoS display. Alternatively or additionally, the image generator can contain at least one DMD device. DMD devices (DMD = Digital Mirror Device) are well known from the prior art and enable image generation using an array of a plurality of movable micromirrors.

[0018] In a further preferred embodiment, the lighting device according to the invention is an interior lighting device for generating the light distribution on a projection surface in the interior of the motor vehicle. The lighting device can be designed for installation in various positions within the interior, e.g., in the roof lining or in a motor vehicle seat. Likewise, the projection surface can be located at various locations within the interior. For example, the light distribution can be generated on the back of a backrest of a motor vehicle seat or on the dashboard of the motor vehicle, or at any other desired position.

[0019] The lighting device according to the invention can also be used to illuminate the exterior of the motor vehicle. In a preferred variant, the lighting device is an ambient lighting device for generating the light distribution on a projection surface on the ground in the vicinity of the motor vehicle.

[0020] In addition to the lighting device described above, the invention relates to a motor vehicle which comprises one or more of the lighting devices according to the invention or one or more preferred variants of the lighting device according to the invention.

[0021] Embodiments of the invention are described in detail below with reference to the attached figures.

[0022] They show:

[0023] Fig. 1 is a schematic perspective view of an embodiment of a lighting device according to the invention;

[0024] Fig. 2 is a schematic plan view of the illumination device of Fig. 1, wherein the projection optics are arranged in a first fixing position on the image generator; and

[0025] Fig. 3 is a schematic plan view analogous to Fig. 2, wherein the projection optics are arranged in a second fixing position on the image generator.

[0026] An embodiment of the lighting device according to the invention is described below using an interior lighting device for a motor vehicle. This lighting device generates a light distribution on a corresponding projection surface in the interior of the motor vehicle. However, the lighting device according to the invention is not limited to interior lighting devices, but can also be used as an exterior light for the exterior of a motor vehicle. In particular, the lighting device can be used as an ambient lighting device in order to generate a light distribution on the ground in the vicinity of the motor vehicle. Fig. 1 shows a perspective view of an embodiment of a lighting device according to the invention. The lighting device comprises a projection device 1 which contains an image generator 2 and projection optics 3.During operation of the projection device 1, the projection optics 3 are attached to the image generator 2. In Fig. 1, however, the projection optics are shown spaced apart from the image generator in order to expose the manner of attachment of the projection optics to the image generator described below.

[0027] Both the image generator 2 and the projection optics 3 are shown only schematically. These two components are separate modules enclosed by a separate housing. In other words, the image generator 2 is enclosed by a housing 201, whereas the image generator 3 is enclosed by a housing 301. Both the image generator 2 and the projection optics 3 contain components or assemblies known per se, which are only partially visible in Fig. 1 and will not be described in detail below.

[0028] The projection device 1 has very compact dimensions. When the projection optics 3 are attached to the image generator 2, the length (i.e., the maximum extension from left to right in Fig. 1), the height (i.e., the maximum extension from bottom to top in Fig. 1), and the depth (i.e., the maximum extension from front to back in Fig. 1) of the projection device are each less than or equal to 100 mm. For example, the length can be 80 mm, the height 30 mm, and the depth 50 mm.

[0029] The image generator 2 contains a merely schematically indicated light source 202, which can be designed, for example, as an RGB LED to generate light of different colors. The light from the light source 202 falls on the unit 203, which generates an image B from this light in a manner known per se. In the embodiment described here, the unit 203 is a so-called DMD device, which is known per se from the prior art. This device contains a plurality of movable micromirrors, which are digitally controlled to generate a corresponding image based on digital image information. In the embodiment of Fig. 2, the DMD device contains a prism arrangement to direct the light radiation from the light source 202 onto the micromirrors that generate the image B. From the micromirrors, the light enters the projection optics 3 via an opening in the left part of the front of the housing 201.

[0030] Instead of a DMD device, any other unit can be used with which an image is generated from the light of the illuminant 202. In particular, an LCD display or an LCoS display can be used, for example. An LCD display and an LCoS display also generate a corresponding image B based on digital image information. In other words, a DMD device, an LCD display, and an LCoS display each represent a digital image generator that is electrically controlled and generates the image B based on digital image information. These image generators have the advantage that the generated image is changeable and, if necessary, animated images can also be generated. Nevertheless, instead of a digital image generator, an analog image generator can also be used in the lighting device according to the invention, with which the image B is generated via a slide.

[0031] During operation in projection direction 1, the housing 301 of the projection optics 3 is attached to the front of the housing 201 of the image generator 2. The attachment is achieved via a guide in the form of two guide rails 4, which run parallel along the long side of the housing 201 of the image generator 2. The housing 301 can be slid onto the housing 201 via corresponding rails on the rear of the housing 301 of the projection optics 3. The housing 301 can be fixed in various fixing positions on the housing 201. For this purpose, suitable locking means can be provided in a conventional manner on the guide rails 4 of the housing 201 or on the corresponding rails of the housing 301 (not shown).

[0032] To set a fixing position, the embodiment in Fig. 2 uses a spacer element 5, which is only schematically indicated by a hatched rectangle. This spacer element can be inserted between the guide rails 4 and abuts against the right edge of the two guide rails. If the housing 301 is pushed onto the housing 201, the spacer element 5 forms a stop against which the right side of the housing 301 abuts. This establishes the corresponding fixing position of the projection optics 3 on the housing 201 of the image generator 2. To arrange the projection optics 3 in a different fixing position, the spacer element 5 can be replaced with a different spacer element of a different size. Alternatively, it is also possible to insert further spacers, whereby the stop for the projection optics 3 is increasingly shifted to the left.

[0033] The projection optics 3 contains, in a manner known per se, an arrangement of projection lenses (not shown), via which the image B is projected onto a corresponding projection surface in the interior of the motor vehicle, as will be explained in more detail below with reference to Fig. 2 and Fig. 3. The light cone which falls onto the projection surface exits the housing 301 via a light exit opening 302. An aspect of the lighting device in Fig. 1 which is essential to the invention is that the housing 301 is replaceably fastened to the housing 201. In this way, it is possible to change the projection of the image B generated in the image generator 2 without changing the image content itself. As a result, the projection device 1 can be easily adapted to specific conditions in the motor vehicle or different distances between the projection device and the projection surface. For example, a conventional projector can be converted into a so-calledA short-throw projector can be made by using a wide-angle lens as the projection lens. In this sense, the projection lens can be viewed as a lens that can be swapped around, similar to a camera, to change the projection. Nevertheless, the generated image B projected via the projection lens remains unchanged.

[0034] Fig. 2 shows a schematic plan view of the projection device 1 from Fig. 1, wherein the projection optics 3 is fastened to the front of the housing 201 of the projector 2 in a first fixing position. The fixing position is selected such that the left side surface of the housing 301 is flush with the left side surface of the housing 201. Fig. 2 also schematically shows the projection effected by the projection device 1. This is formed by a light distribution LV on a projection surface PF. The light cone of the projection is indicated by two dashed lines. The optical axis O of the projection optics 3 is represented by a dotted line. In the fixing position of Fig. 2, the optical axis O is located centrally in the image B generated by the image generator 2. As a result, a symmetrical projection cone is generated.

[0035] Fig. 3 is a representation analogous to Fig. 2, but with the projection optics 3 arranged in a different fixing position. In this fixing position, the optical axis O is shifted to the right compared to the fixing position in Fig. 2. As a consequence, the optical axis is no longer centered in the generated image B. This results in an asymmetrical light cone falling on the projection surface PF, distorting the light distribution LV and the projected image. By arranging the projection optics at different fixing positions, the shape of the light cone and thus the projection of the corresponding image can be adapted depending on the conditions in the interior of the motor vehicle.

[0036] The embodiment of the invention described above offers a number of advantages. In particular, a lighting device for a motor vehicle is created whose projected light distribution can be easily adjusted by replacing a projection optics. Furthermore, the projection optics can be arranged at different fixing positions on the image generator, allowing the light cone of the projection and thus the projected light distribution to be influenced.

[0037] List of reference symbols

[0038] 1 projection device

[0039] 2 Imager 201 Imager housing (first housing)

[0040] 202 lamps

[0041] 203 DMD device

[0042] 3 Projection optics

[0043] 301 Housing of the projection optics (second housing) 302 Light exit opening of the projection optics

[0044] 4 guide rails

[0045] 5 spacer element

[0046] B image generated by the image generator

[0047] O optical axis of the projection optics LV generated light distribution

[0048] PF projection screen

Claims

Claims 1. Lighting device for a motor vehicle, comprising a projection device (1) with an image generator (2) which is designed to generate an image (B) from the light of a lighting means (202), and with projection optics (3) which are designed to generate a light distribution (LV) on a projection surface (PF) by projecting the image (B) generated by the image generator (2) onto the projection surface (PF), characterized in that the image generator (2) is enclosed by a first housing (201) and the projection optics (3) are enclosed by a second housing (301), wherein the first housing (201) and the second housing (301) are separate housings and the second housing (301) is replaceably fastened to the first housing (201).

2. Lighting device according to claim 1, characterized in that the second housing (301) can be removed from the first housing (201) and reattached thereto without tools.

3. Lighting device according to claim 1 or 2, characterized in that the second housing (301) is screwed to the first housing (201) or is fastened to the first housing (201) via a bayonet lock.

4. Lighting device according to claim 1 or 2, characterized in that the second housing (301) is pushed onto the first housing (201) via a guide (4).

5. Lighting device according to one of the preceding claims, characterized in that the second housing (301) can be fixed to the first housing in different fixing positions, wherein the optical axis (O) of the projection optics (3) is positioned differently in the different fixing positions.

6. Lighting device according to claim 5, characterized in that the optical axis (O) is shifted parallel in the different fixing positions.

7. Lighting device according to claim 5 or 6 in combination with claim 4, characterized in that one or more spacer elements (5) are arranged on the guide (4), via which the fixing position is set.

8. Lighting device according to one of the preceding claims, characterized in that the image generator (2) is a digital image generator which generates the image (B) based on digital image information.

9. Lighting device according to claim 8, characterized in that the image generator comprises at least one LCD display and / or at least one LCoS display and / or at least one DMD device.

10. Lighting device according to one of the preceding claims, characterized in that the lighting device is an interior lighting device in order to generate the light distribution (LV) on a projection surface (PF) in the interior of the motor vehicle.

11. Lighting device according to one of claims 1 to 9, characterized in that the lighting device (1) is an ambient lighting device in order to generate the light distribution (LV) on a projection surface (PF) on the ground in the surroundings of the motor vehicle.

12. Motor vehicle, characterized in that the motor vehicle comprises one or more lighting devices according to one of the preceding claims.

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