Display device for a vehicle

Abstract

The invention relates to a display device for a vehicle, which is designed to be integrated into the interior of the vehicle, comprising a plurality of light sources (1), a plurality of light guides (2), each of which has an entry surface (6) and a reflective region (7), and a plurality of holograms (8), wherein: at least one of the holograms (8) is arranged on or in each of the light guides (2); at least one of the light sources (1) in each case is assigned to one of the light guides (2); and the display device is designed such that light (3) emitted from the light sources (1) enters the entry surface (6) of the assigned light guide (2) in the direction of the reflective region (7), is reflected by the reflective region (7) in the interior of the light guide (2) in the direction of the hologram (8), and interacts with the hologram (8).

Description

[0001] Display device for a vehicle

[0002] Description

[0003] The present invention relates to a display device for a vehicle which is designed to be integrated into the interior of the vehicle.

[0004] There are indicator devices in the interior of a vehicle that serve as warning lights, for example, for the lane change assistant or the blind spot warning function. If an overtaking vehicle is detected in the rear blind spot, which is not visible to the driver via the side mirror, a small warning light illuminates in or on the exterior mirror, or inside the mirror base or the front corner of the side window. A similar function is then also used, for example, when the driver changes lanes, possibly even unintentionally, as a lane change assistant or lane departure warning system.

[0005] Holographic lighting systems can enhance and enhance the design of such a warning function and create scenarios with impressive depth and a 3D appearance, with the advantage of attracting greater attention and thus increasing safety than today's small illuminated surfaces, which can be easily overlooked.

[0006] It is desirable to integrate holograms into lighting systems or display devices in vehicle interiors with the aim of further developing existing, simple warning or information lights into display devices with a three-dimensional illuminated image. This leads to increased attention and recognition, and thus to increased driving safety. Furthermore, holographic display functions provide a basis for the trend toward individualization and personalization, as the hologram can be customized with various, customized graphics and displays.This makes it very easy to provide different appearances while retaining the optical components, which cannot be achieved without holograms, for example to be able to easily use cultural, country-specific graphics and pictograms or fonts in different ways and thus to individually adapt the execution of the display function to global requirements.

[0007] The installation of display devices in vehicle interior trim elements is characterized by tight installation spaces and shallow depths, as other components, such as cable harnesses, absorption components, loudspeakers, airbag supply lines, or the airbags themselves, are often installed in the trim. Another reason for tight installation spaces and shallow depths can be a correspondingly strongly shaped body structure or supporting structure, which is formed with multiple sheets or components to ensure the rigidity of the passenger cell and guarantee occupant protection in the event of a crash.

[0008] A display device of the type mentioned above is known from DE 10 2019 206 025 A1. The display device described therein is used to display image information in the interior of a vehicle. The display device comprises a light source designed as a light-emitting diode (LED) and a flat light guide, into the end face of which the light from the light source is coupled. The coupled light is totally reflected several times between the front and rear interfaces of the light guide and thus guided through the entire light guide surface. Several holograms, designed as reflection holograms, are arranged in the light guide approximately centrally between the front and rear interfaces. The interaction of the light with the holograms creates several holographic images that can be perceived by a user in the interior of the vehicle.It is possible that, in such flat systems, the multiple light reflections at the front and rear interfaces are visible as images of alternating bright and dark stripes in the reconstructed hologram. Furthermore, in such systems, the angle at which the light is reflected at the front and rear interfaces must correspond to the illumination angle of the hologram, which is associated with relatively high complexity. The problem underlying the present invention is to create a display device of the type mentioned above that is simple in design and / or requires little installation space.

[0009] This is achieved according to the invention by a display device of the type mentioned above with the features of claim 1. The subclaims relate to preferred embodiments of the invention.

[0010] According to claim 1, the display device comprises a plurality of light sources, a plurality of light guides, each having an entrance surface and a reflective region, the light guides being arranged next to one another, and a plurality of holograms, at least one of the holograms being arranged on or in each of the light guides, at least one of the light sources being assigned to one of the light guides, and the display device being set up such that light emanating from the light sources enters the entrance surface of the assigned light guide in the direction of the reflective region, is reflected by the reflective region in the interior of the light guide in the direction of the hologram, and interacts with the hologram.

[0011] This allows the display device to be designed very compactly. In particular, the light is reflected directly from the reflective area toward the hologram, thus avoiding multiple reflections and the associated bright and dark bands in the reconstructed hologram. It can be provided that the direction in which the light guides are arranged next to one another is either horizontal or vertical when the display device is installed in the vehicle. The light guides can therefore also be arranged one above the other.

[0012] It can be provided that the average distance between each of the light sources and the reflective region of the associated light guide is at least half the average distance from the reflective region to the hologram, in particular wherein the average distance between the light source and the entrance surface together with the average distance between the entrance surface and the reflective region is between 0.8 and 1.2 times the average distance between the reflective region and the hologram. The average distance between the entrance surface and the reflective region can be at least half the average distance from the reflective region to the hologram and / or the average distance between the light source and the entrance surface of the associated light guide can be at least half the average distance between the reflective region and the hologram.The large distance between the light source and the reflective area creates a long path for the light emitted by the light source to spread transversely. This allows for a large width and a space-saving, compact design of the light guides, allowing the display device to be easily integrated even into small installation spaces.

[0013] The display device can be designed so compactly that it is suitable for installation in different positions in the vehicle interior, for example integrated into the A-pillar, B-pillar or C-pillar or in the dashboard or in the center console or in the roof console or in the doors or at any other location in the vehicle interior.

[0014] It is possible for two light sources to be assigned to each of the light guides and for each of the light guides to have two entry surfaces and two reflective regions, wherein the display device is configured such that light emanating from the first of the two light sources enters the first of the two entry surfaces of the light guide in the direction of the first of the reflective regions, is reflected by the first reflective region inside the light guide in the direction of the hologram and interacts with the hologram, and that light emanating from the second of the two light sources enters the second of the two entry surfaces of the light guide in the direction of the second of the reflective regions, is reflected by the second reflective region inside the light guide in the direction of the hologram and interacts with the hologram.This allows the display device or light guide to illuminate the hologram from two directions despite its compact dimensions, for example by providing opposing light sources that cross over and introduce light into the entrance surface opposite the respective light source. It can be provided that two holograms are arranged on each of the light guides, in particular wherein the display device is configured such that a first of the two holograms interacts with the light emanating from the first light source and the second of the two holograms interacts with the light emanating from the second light source. This allows two different holographic images to be generated by one light guide.

[0015] Furthermore, it can be provided that the light emitted by the first light source has a different wavelength distribution, in particular a different color, than the light emitted by the second light source. This allows the light guide to be used for two different light colors, for example, red and yellow, red and blue, or red and green, in order to display two functions or different warnings and instructions for each of the light colors using a hologram.

[0016] It is possible for each of the light guides to be U-shaped with two legs and a connecting area between the two legs. This creates a compact component that is easy to install in the interior of a vehicle.

[0017] The first entry surface, and in particular also the first reflective region, can be arranged on the first of the two legs, the second entry surface, and in particular also the second reflective region, can be arranged on the second of the two legs, and the hologram(s) can be arranged on or in the connecting region. This allows for a very compact design of the display device.

[0018] It can be provided that the first light source is arranged on the second leg or in the region of the second leg, and the second light source is arranged on the first leg or in the region of the first leg, wherein the display device comprises, in particular, a holder for the light sources or a holder for each of the light sources. As a result, the hologram or holograms are illuminated from two different directions, with the light sources, for example, located opposite one another, introducing light into the entrance surface opposite the light source in a crossing manner. This results in two folded beam paths that contribute to the compactness of the display device.

[0019] It is possible for the display device to be configured so that, through the interaction of the light with the holograms arranged on or in the individual light guides, an image composed of several individual holographic images is generated. This increases the area for a holographic display.

[0020] It can be provided that the display device is configured to control the plurality of light sources such that the individual holographic images generated by the interaction of the light with the holograms arranged on or in the individual light guides are generated at different times, in particular in order to generate a dynamic or animated composite image. For example, upon activation and / or deactivation of the display function, the plurality of light sources can be controlled sequentially, thereby introducing a dynamic or animation into the holographic display that increases attention and further enhances safety. For example, this can also provide a warning for the driver with a hazard level.

[0021] It is possible for the display device to comprise a holding device on or in which the plurality of light sources and the plurality of light guides with the plurality of holograms are held. A common holding device simplifies the alignment of the individual parts relative to one another.

[0022] It can be provided that the holding device comprises at least one light-shading element to at least partially prevent unwanted light from entering the plurality of optical fibers, wherein the at least one light-shading element is preferably arranged in a connecting region between individual optical fibers and / or extends from a connecting region between individual optical fibers. This can, in particular, reduce the occurrence of double images or blurring in adjacent holographic images.

[0023] It is possible for the display device to comprise a housing and / or at least one cover plate and / or at least one design panel. This can be a common cover plate for all of the light guides. Furthermore, a design panel can be provided that surrounds the light exit surfaces of the light guides.

[0024] It can be provided that the display device is designed to be integrated into an A-pillar or a B-pillar or a C-pillar or a dashboard or a center console or a roof console or a door of the interior of the vehicle

[0025] The invention is explained in more detail below with reference to the accompanying drawings. In the drawings:

[0026] Fig. 1 is a perspective view of part of a display device according to the invention, of which only a light guide and the associated light sources are shown;

[0027] Fig. 2 is a further perspective view of the part of the display device according to Fig. 1;

[0028] Fig. 3 is a sectional view of the part of the display device according to Fig. 1 with an exemplary beam path of the light emanating from one of the light sources;

[0029] Fig. 4 is a perspective view of the display device, showing several light guides and the associated light sources;

[0030] Fig. 5 is a further perspective view of the display device according to Fig. 4; Fig. 6 is a front view of the display device according to Fig. 4 with a housing;

[0031] Fig. 7 is a perspective view of the display device according to Fig. 4 with the housing without cover plate;

[0032] Fig. 8 is a perspective view of the display device according to Fig. 4 with the housing without cover plate and without design panel;

[0033] Fig. 9 is a perspective view of the display device according to Fig. 4 with a holding device without a housing;

[0034] Fig. 10 is a further perspective view of the display device according to Fig. 4 with the holding device without a housing;

[0035] Fig. 11 is a detail of a perspective view of the display device according to Fig. 4 with the holding device without a housing, wherein an exemplary beam path of the light emanating from one of the light sources is depicted;

[0036] Fig. 12 is a side view of the display device according to Fig. 4 with the holding device without a housing, wherein an exemplary beam path of the light emanating from one of the light sources is depicted;

[0037] Fig. 13 shows a further detail of a perspective view of the display device according to Fig. 4 with the holding device without a housing;

[0038] Fig. 14 is a vertical section through the display device according to Fig. 4;

[0039] Fig. 15 shows a horizontal section through the display device according to Fig. 4; Fig. 16 shows a first embodiment of an image generated by a display device according to the invention;

[0040] Fig. 17 shows a second embodiment of an image generated by a display device according to the invention.

[0041] In the figures, identical and functionally identical parts are provided with the same reference numerals.

[0042] The part of the display device depicted in Fig. 1 to Fig. 3 comprises two light sources 1 and a light guide 2. The light sources 1 are designed, in particular, as light-emitting diodes (LEDs). Alternatively, the light sources 1 can also be designed as laser diodes.

[0043] The light guide 2 consists at least partially of a material that is transparent to the light 3 from the light sources 1. The light guide 2 is essentially U-shaped with two legs 4 and a connecting region 5 between the two legs. The light guide 2 can be comparatively compact and, for example, have dimensions between 20 mm and 40 mm in width, height, and depth, in particular a height in Fig. 3 of approximately 35 mm and a width and depth of approximately 25 mm.

[0044] The light guide 2 has two entry surfaces 6 for the light 3 from the light sources 1. In this case, one of the entry surfaces 6 is arranged on the inside of one of the legs 4. The light sources 1 are each arranged next to the end of one of the legs 4 in such a way that the light 3 emanating from the light source 1 enters the entry surface 6 of the other of the legs 4 (see Fig. 3). In this way, the light 3 travels a comparatively long path from the light source 1 to the entry surface 6, which allows a suitably large extension of the light beam entering the entry surface 6. The two entry surfaces 6 are curved, in particular concavely curved. However, it is certainly possible for the entry surfaces to be convexly curved or flat.

[0045] The light guide 2 further comprises two reflective regions 7 formed on the outer sides of the legs 4. The light 3 entering the light guide 2 through the entrance surfaces 6 is reflected by these reflective regions 7 into the connecting region 5. The display device can be configured such that the light 3 impinges on the reflective region 7 at an angle to the normal that is greater than the critical angle of total reflection, so that the light 3 is totally reflected if the surface of the reflective region 7 is correspondingly smooth. Alternatively or additionally, the surface of the reflective region 7 can be mirrored.

[0046] The connecting region 5 forms an exit surface on the side facing away from the legs 4, onto which the light 3 emanating from the reflective regions 7 impinges and through which the incident light 3 at least partially passes. The part of the display device depicted in Fig. 1 to Fig. 3 further comprises a hologram 8, which is applied, in particular glued, to the exit surface from the outside, particularly in the form of a volume hologram read into a film. The image read into the hologram 8 can be reconstructed to implement a desired display function.

[0047] Hologram 8 is a transmission hologram, with which the light passing through the exit surface can interact. With a sufficiently large angle of incidence between the incident light 3 and the normal on the exit surface, hologram 8 is also an edge lit hologram, because then the illumination angle at which hologram 8 must be illuminated to reconstruct the holographic image becomes comparatively large.

[0048] The comparatively large illumination angle prevents, in particular, the Ote order of the used light from becoming disturbingly visible to an observer. The reflective regions 7 are convexly curved and, in particular, designed as a paraboloid surface. This curvature ensures that the portions of the light 3 impinging on the reflective regions 7 at different angles are reflected essentially in the same direction into the connecting region 5. The essentially parallel light rays of the light 3 ensure essentially identical illumination angles of the hologram 8, which is advantageous for effective reconstruction of the holographic image.

[0049] Alternatively, the reflective regions 7 may be designed as free-form surfaces to enable further optimization of the illumination or optimal adaptation to the coupled light 3 of the light sources 1. The reflective regions 7 may alternatively be provided with additional optics depending on the desired light shaping of the reflected light 3.

[0050] Due to the comparatively long path that the light travels from the light source 1 to the reflecting region 7, the latter can be comparatively completely illuminated, in particular in the direction extending into the plane of the drawing in Fig. 3, so that despite the compactness of the light guide 2, the illumination of a comparatively wide hologram 8 is also possible.

[0051] It can be provided that two holograms 8 are arranged on the light guide 2. These can both be applied, for example, one above the other, to the outside of the exit surface of the light guide 2. In particular, both holograms 8 can be read into the same foil. The holograms 8 can be written with light of different wavelengths, so they must also be reconstructed with light of different wavelengths.

[0052] In this case, the two light sources 1 can have different wavelength distributions, in particular different colors. Thus, the light guide 2 can be used for two different light colors, for example, red and yellow, red and blue, or red and green, in order to reconstruct two different images for each of the light colors using a hologram 8.

[0053] Alternatively, it is also possible to provide only one hologram 8 as well as only one light source 1, one entrance surface 6, and one reflective area 7. In this case, the height of the light guide can be reduced because an entire coupling and reflection area is not used.

[0054] Figs. 4 to 15 illustrate that the display device comprises a plurality of optical fibers 2, of which three optical fibers 2 arranged next to one another are depicted in Figs. 4 to 15. The number of optical fibers 2 is chosen merely as an example. Only two optical fibers 2 arranged next to one another may be provided. Alternatively, more than three optical fibers 2 arranged next to one another may be provided, for example, four optical fibers 2 or five optical fibers 2 or more than five optical fibers 2.

[0055] Two light sources 1 are each assigned to the three light guides 2, with three of the light sources 1 being arranged on a common circuit board 9, which extends in the direction in which the light guides 2 are arranged next to one another. The light sources 1 assigned to the respective light guide 2 are arranged as illustrated in Figs. 1 to 3.

[0056] At least one hologram 8 is provided per light guide 2 so that adjacent holographic images can be reconstructed by interaction with the light 2 of the respective light sources 1.

[0057] The embodiment of a display device shown in Figs. 4 to 15 comprises a holding device 10 and a housing 11 which surrounds the light guides 2 at the rear and sides. A cover plate 12 and a design panel 13 are arranged on the front of the housing 11. The cover plate 12 covers the exit surfaces or the holograms 8 of the light guides 2. The design panel 13 surrounds the exit surfaces or the holograms 8 of the light guides 2 in order to achieve an attractive design of the display device. Depending on the installation situation of the display device in the vehicle, it is possible to dispense with the cover plate 2, for example if a larger cover plate is provided at the installation location behind which the display device can be placed. The housing 11 can also be dispensed with if it is not necessary in a protected installation environment.

[0058] The holding device 10 has two light shading elements 14 on the rear side of the light guides 2 or on the side of the light guides 2 facing away from the exit surface. The two light shading elements 14 each originate from a connection region between individual light guides 2 and extend from the light guides 2 into the space between the circuit boards 9. In this way, the light shading elements 14 can at least partially prevent unwanted light from a light source 1 from entering the light guide 2 assigned to an adjacent light source 1 (see in particular Fig. 11). This can, in particular, reduce the occurrence of double images or blurring in adjacent holographic images.

[0059] The holding device 10 comprises further light shading elements 15, 16, which cover parts of the light guides 2 in order to largely prevent unwanted light from one of the light sources from entering the light guides 2 (see in particular Fig. 14).

[0060] The display device can, for example, fulfill a warning and information function. For this purpose, the display device can control the plurality of light sources 1 such that the individual holographic images reconstructed by the interaction of the light 3 with the holograms 8 arranged on or in the individual light guides 2 are generated at different times, in particular in order to create a dynamic or animated composite image. For example, upon activation and / or deactivation of the display function, the plurality of light sources 1 can be controlled sequentially, thereby introducing a dynamic or animation into the holographic display, which increases attention and further enhances safety. For example, this can also provide a warning for the driver with a gradation of danger.

[0061] Fig. 16 shows the display of a display device composed of three holographic images 17. The display device can be part of a blind spot assistant and can indicate a vehicle located in a blind spot with an animation.

[0062] Fig. 17 shows the display of a display device, which is also composed of three holographic images 17. The display device can be part of a lane change assistant and can indicate an oncoming vehicle preventing the lane change with an animation.

[0063] As image 17, any pictograms, texts or other content of any kind can be stored in the at least one hologram 8.

[0064] The generated images 17 can be animated in both directions—from top to bottom or vice versa, or from left to right or vice versa. Additionally, the brightness of the individual objects in the holographic image 17 or of the individual sections of the image can be varied; for example, the brightness can be varied from low to bright for a graduated warning effect.

[0065] Depending on the installation location in the vehicle, the viewing angle for the holographic function can be defined differently. For example, if a blind spot warning system and lane change assistant are provided as functional elements in the A-pillar, the viewing area of ​​the left, driver-side hologram function and the other viewing area for the right, passenger-side hologram function can be restricted to the driver's position. By using a hologram, the eyebox or the viewing angle can be limited to the driver only, so that a high luminance or brightness can be achieved in the holographic system even with little light. Irrespective of this, any desired eyebox can be defined and implemented for other installation situations, either for a specific seat in the vehicle or for multiple seats.

[0066] List of reference symbols

[0067] 1 light source

[0068] 2 light guides

[0069] 3 Light emanating from the light source

[0070] 4 legs of the light guide

[0071] 5 Connection area between the legs of the light guide

[0072] 6 Entrance surface of the light guide

[0073] 7 reflective area of ​​the light guide

[0074] 8 hologram

[0075] 9 common circuit board of the light sources

[0076] 10 Holding device

[0077] 11 housings

[0078] 12 Cover plate

[0079] 13 Design panel

[0080] 14 Light shading element

[0081] 15 Light shading element

[0082] 16 Light shading element

[0083] 17 holographic image

Claims

Patent claims 1. Display device for a vehicle, designed to be integrated into the interior of the vehicle, comprising - a plurality of light sources (1 ), - a plurality of optical fibers (2), each having an entry surface (6) and a reflecting area (7), wherein the optical fibers (2) are arranged next to each other, as well as - a plurality of holograms (8), wherein at least one of the holograms (8) is arranged on or in each of the light conductors (2), - wherein at least one of the light sources (1 ) is assigned to one of the light guides (2) and the display device is configured so that light (3) emanating from the light sources (1) enters the entry surface (6) of the assigned light guide (2) in the direction of the reflecting area (7), is reflected by the reflecting area (7) inside the light guide (2) in the direction of the hologram (8) and interacts with the hologram (8).

2. Display device according to claim 1, characterized in that the mean distance between each of the light sources (1) and the reflecting area (7) of the associated light guide (2) is at least half as large as the mean distance from the reflecting area (7) to the hologram (8), in particular wherein the mean distance between the light source (1) and the entrance surface (6) together with the mean distance between the entrance surface (6) and the reflecting area (7) is between 0.8 and 1.2 times as large as the mean distance between the reflecting area (7) and the hologram (8).

3. Display device according to claim 2, characterized in that the mean distance between the entry surface (6) and the reflecting area (7) is at least half as large as the mean distance from the re- The display device according to one of claims 1 to 3 is characterized in that each of the light guides (2) is associated with two light sources (1) and that each of the light guides (2) has two entry surfaces (6) and two reflective areas (7), wherein the display device is configured such that light (3) emanating from the first of the two light sources (1) enters the first of the two entry surfaces (6) of the light guide (2) in the direction of the first of the reflective areas (7), is reflected by the first reflective area (7) inside the light guide (2) in the direction of the hologram (8) and interacts with the hologram (8).and that light (3) emanating from the second of the two light sources (1) enters the second of the two entry surfaces (6) of the light guide (2) in the direction of the second of the reflective areas (7), is reflected by the second reflective area (7) inside the light guide (2) in the direction of the hologram (8), and interacts with the hologram (8). Display device according to one of claims 1 to 4, characterized in that two holograms (8) are arranged on each of the light guides (2), in particular wherein the display device is configured such that a first of the two holograms (8) interacts with the light (3) emanating from the first light source (1) and that the second of the two holograms (8) interacts with the light (3) emanating from the second light source (1). Display device according to one of claims 4 or 5, characterized in that the light (3) emanating from the first light source (1), a different wavelength distribution, in particular a different color, than the light (3) emitted by the second light source (1). Display device according to any one of claims 1 to 6, characterized in that each of the light guides (2) is U-shaped with two legs (4) and a connecting region (5) between the two legs (4). Display device according to claim 7, characterized in that the first entry surface (6), and in particular also the first reflective region (7), is arranged on the first of the two legs (4), that the second entry surface (6), and in particular also the second reflective region (7), is arranged on the second of the two legs (4), and that the hologram (8) or holograms (8) are arranged on or in the connecting region (5).A display device according to any one of claims 4 to 8, characterized in that the first light source (1) is arranged on or in the region of the second leg (4) and the second light source (1) is arranged on or in the region of the first leg (4), wherein the display device in particular comprises a holder for the light sources (1) or a holder for each of the light sources (1). A display device according to any one of claims 1 to 9, characterized in that the display device is configured such that an image composed of several individual holographic images (17) is generated by the interaction of the light (3) with the holograms (8) arranged on or in the individual light guides (2).Display device according to one of claims 1 to 10, characterized in that the display device is configured to control the plurality of light sources (1 ) in such a way that the interaction. The individual holographic images (17) generated by the light (3) and the holograms (8) arranged on or in the individual light guides (2) are generated with a temporal offset from one another, in particular to generate a dynamic or animated composite image. Display device according to one of claims 1 to 11, characterized in that the display device comprises a holding device (10) on or in which the plurality of light sources (1) and the plurality of light guides (2) with the plurality of holograms (8) are held.Display device according to claim 12, characterized in that the holding device (10) comprises at least one light-shading element (14, 15, 16) to at least partially prevent unwanted light from entering the plurality of light guides (2), wherein the at least one light-shading element (14, 15, 16) is preferably arranged in a connection area between individual light guides (2) and / or extends from a connection area between individual light guides (2). The device also comprises a housing (11) and / or at least one cover plate (12) and / or at least one design aperture (13). Display device according to any one of claims 1 to 14, characterized in that the display device (10) is configured to be integrated into an A-pillar, a B-pillar, a C-pillar, a dashboard, a center console, a roof console, or a door of the vehicle interior.

Images