DISPLAY DEVICE FOR A VEHICLE

Abstract

A display device for a vehicle, comprising a display surface having a display side for displaying information in the direction of a viewer and a rear side facing away from the display side, a light-guiding device having at least one light source, wherein the light-guiding device has at least one transparent light-guiding layer which extends in front of the display side and at least partially covers the display side, wherein the at least one light-guiding layer has at least one decoupling region in at least one partial area of ​​the display side for decoupling the light of the at least one light source in the direction of the viewer, and wherein the at least one decoupling region is designed for the information displayed via the display side to be superimposed by the decoupled light.

Description

The present invention relates to a display device for a vehicle.From the prior art, display devices for vehicles have already become known, which display devices have a display surface with a display side for reproducing information in the direction of a viewer and a rear side facing away from this display side.It is also known from the prior art to display, for example, warning symbols and further notification symbols for a viewer, in the area of the display device for vehicles dedicated surface areas of the display surface.However, the disadvantage here is that the entire display device must be operated in order, for example, to be able to display the warning symbols via the display device, which requires, in particular, increased energy consumption. It is also disadvantageous that the actual area of the display, by providing dedicated display subareas for the display of warning symbols, reduces the available display area for the reproduction of information. Furthermore, according to the prior art, there is the disadvantage that the display of the warning symbols is dependent on the functionality of the entire display device, and if this fails, it is precisely also not possible for warning or notification symbols to be output any longer for the viewer.On the basis of the aforementioned disadvantages of the known display devices from the prior art, the object of the present invention is to provide an improved display device for reproducing information and representations of light signals for a viewer, wherein the display device according to the invention can display light signals independently of the actual display surface for reproducing information and in the region of the actual display surface.The object of the present invention is achieved by a display device for a vehicle having a display surface which has a display side for reproducing information in the direction of a viewer and a rear side facing away from this display side, and having a light guide device having at least one light source.According to the invention, the light guide device has at least one transparent light guide layer which extends in front of the display side and at least partially covers the display side, wherein the at least one light guide layer has at least one decoupling region in at least one partial surface region of the display side for decoupling the light of the at least one light source in the direction of the observer, and wherein the at least one decoupling region is designed for superimposing the information reproduced via the display side by the decoupled light.According to the invention, it is made possible, by means of the light guide layer, which has a decoupling region in a partial surface region of the display side, to emit or emit additional light signals in the direction of the observer of the display surface by the arrangement of the light guide device in front of the actual display side of the display surface. In this case, the light can be superimposed over the image information of the actual display side via the at least one decoupling region, accordingly that although the reproduced information on the display side is still visible in all regions, an additional light signal is superimposed on the observer in the region of the at least one decoupling region.The light signal and the at least one decoupling region can also be formed such that, as a result of the light decoupling via the at least one decoupling region, the information reproduced via the display surface is completely superimposed by the emitted light of the light guide layer and therefore only the light signal emitted via the light guide device is visible to the observer in the region of the decoupling region. Furthermore, the display device provided according to the invention makes it possible for a viewer to also output light signals only via the light-conducting layer, if no information at all is displayed via the display surface. The light guide device thus forms an additional layer for outputting light information to the observer, which is independent of the actual display surface. The output of the light information to the observer via the light guide device can in this case be independent of the reproduction of the information of the display side, wherein, for example, optical warning signals neither output the observer. Alternatively, the light information can be output via the light guide device intentionally in coordination with the information reproduced via the display side, for example in order to point out the user to the information displayed on the display side of the display area or to highlight certain information.According to the invention, it can be provided that the display surface is transmissive at least in a first sub-region and wherein the information of the display surface to be reproduced is projected onto the rear side of the display surface by a rear projection device.It can also be provided that the display surface is reflective at least in a second sub-region and wherein the information of the display surface to be reproduced is projected onto the display side of the display surface by a front-side projection device.Of course, according to the invention, in preferred embodiments, the display surface can be embodied as either fully transmissive or fully reflective.According to the invention, it can be provided that the display device has a projection device for projecting the information to be reproduced on the display surface. The projection device can be selected from the group of an LCD projector, an LCOS projector, an LBS projector or a DLP projector. The abbreviation LCD stands for "liquid crystal display" and is therefore intended to represent a liquid crystal display. LCOS stands for liquid crystal on silicone, LBS stands for laser beam scanning and DLP for digital light processing.According to the invention, it can furthermore be provided that the display device additionally has a transparent cover substrate layer which is arranged in front of the light guide device in the direction of the observer and at least partially covers the light guide device. The cover substrate layer can protect the actual display surface from environmental influences and mechanical loads and serve, for example, for reinforcing or supporting the actual display surface.It can be provided that the light guide device and the display surface and preferably the cover substrate layer are laminated to one another. The lamination of the display surface and the cover substrate layer ensures that a major part of the surface of the cover substrate layer is in contact with the display side. This ensures that the cover substrate layer cannot become detached from the display surface and also prevents the layers from being displaced relative to one another. Furthermore, the lamination forms a bond between the cover substrate layer and the display area, which increases the actual display area and in particular increases the bending rigidity of the display area.The cover substrate layer can be formed as a cover glass layer.The at least one decoupling region can be designed for displaying symbols. Symbols are understood according to the invention to mean, for example, arrows, a exclamation symbol, an attention symbol, a line, a square, a circle, etc.The at least one light decoupling region of the light guide device can be formed by the introduction of an optical microstructure in partial regions of the at least one light guide layer.It can be provided that the at least one light decoupling region of the light guide device is formed by the introduction of an optical microstructure by means of nanoimprinting lithography.It is preferably provided that the at least one decoupling region is formed by forming a microstructure, such as by means of nanoimprinting lithography, for example, on the side of the light guide device facing the viewer and facing away from the display surface. The formation of the at least one light decoupling region via an introduction of a microstructure on the guide layer facing the observer has the advantage here that the light of the at least one light source of the light guide device is emitted directly in the direction of the observer and does not have to be reflected again by the display layer in the direction of the observer, for example.Furthermore, it can be provided that the at least one decoupling region is formed by introducing nanoparticles into the light guide layer in the at least one decoupling region. The nanoparticles can be introduced in defined regions of the light guide, for example during the production of the light guide, if the latter is situated, for example, as a liquid thermoplastic, and the light guide can be cured by cooling.It can be provided that the at least one light conducting layer is formed from a PMMA (polymethyl methacrylate) or a PC (polycarbonate) film.The at least one light source can have a defined light color, preferably a spectral color.It can furthermore be provided that the at least one light source has at least one RGB light source, such as in particular an RGB LED, for the active control of the light color coupled into the at least one light guide layer. The provision of an RGB light source has the advantage that light signals of different colors can be output to the observer via the decoupling region of the light guide device via a light source. For example, the light color can be changed by means of the RGB light source as a function of a warning state for the observer. For example, a green light signal can be used to convey to the viewer that no warnings are present and, for example, the vehicle electronics of a vehicle do not sense errors. In the event of an error condition which does not require any immediate action by the observer, the latter can be output by means of a yellow or orange light signal (for example, refill engine oil, etc.). In urgent warnings, the light color can be output in red color in order to output an urgent warning to the driver via the light signal.Preferably, it can be provided that at least one associated light source is associated with each decoupling region of the light guide layer in order to actively illuminate each decoupling region via the respectively associated at least one light source. This has the advantage that a plurality of decoupling regions can be provided in the light guide layer, which regions are independent of one another for the output of light signals by means of the respective associated light sourceFurthermore, it can be provided that the display surface is designed as an LCD panel and a backlighting unit for backlighting the LCD panel is arranged on the rear side. Alternatively, the display area can be designed according to the invention as an OLED (organic light emitting diode) panel or as an e-ink (bistable) display. In the case of the e-ink display, it can be provided particularly preferably that the e-ink panel is likewise illuminated by the light guide device.The at least one light source of the light guide device is preferably arranged outside the region of the display surface and wherein the light source preferably feeds light generated by the light source via at least one side surface of the at least one light guide layer into the at least one light guide layer.The light guide device can be formed as a continuous light guide layer, which covers the entire display surface in terms of area in the direction of the observer and wherein a plurality of light guides delimited from one another are preferably formed by introducing recesses or cuts into the light guide layer, wherein the light guides are delimited from one another by the cuts or recesses.According to the invention, it can be provided that the microstructures or microparticles introduced into the at least one light-conducting layer are arranged or formed in the surface plane of the light-conducting layer in the form of a symbol.The display surface and the light guide can be formed from an elastically deformable material for realizing a bendable or flexible display device for a vehicle.The following figures show exemplary embodiments of display devices for a vehicle according to the invention.The following are shown: FIG. 1A shows a first exemplary embodiment of a display device according to the invention comprising a transmissive display surface; FIG. 1B shows a second exemplary embodiment of a display device according to the invention having a reflective display surface; FIG. 1C shows a third exemplary embodiment of a display device according to the invention, wherein the display area is formed by an LCD display with backlighting device; FIG. 1D shows a fourth exemplary embodiment of a display device according to the invention, wherein the display area is formed as an OLED panel with an optional cover layer; FIG. 2A is a side view of another embodiment of a display device for a vehicle according to the present invention; FIG. 2B shows the embodiment of the display device according to FIG. 2A in a front view from the direction of the observer; FIG. 3 shows a further display device according to the invention in a view of a viewer.FIG. 1A shows a first exemplary embodiment of a display device for a vehicle. The display device according to the invention has a display surface 1 with a display side 11 for reproducing information in the direction of a viewer 9 and a rear side 12 facing away from the latter. The display device further comprises a light guide device 2 with at least one light source 21, wherein only one singular light source 21 is shown in FIG. 1 for the sake of clarity. The light guide device 2 has at least one transparent light guide layer 20 which extends in front of the display side 11 and at least partially covers the display side 11 of the display surface. In FIG. 1, the light guide layer 20 covers the entire surface of the display surface 1, but embodiments may also be provided in a different manner, wherein only a partial region of the display side 11 is covered by the light guide device 2.Furthermore, the at least one light guide layer 20 has at least one decoupling region 23 in at least one partial surface region of the display side 11 for decoupling the light of the at least one light source 21 in the direction of the observer 9. The at least one decoupling region 23 is configured to superimpose the information reproduced via the display side 11 by the decoupled light from the light guide layer 20.In the embodiment shown in FIG. 1A, the display surface 1 is transmissive over its entire surface, wherein the information of the display surface to be reproduced is projected onto the rear side 12 of the display surface 1 by a rear projection device 8. In FIG. 1A, the image information emitted by the rear projection device 8 onto the rear side 12 of the display surface 1 is shown as arrows with continuous lines, wherein the light coupled out via the coupling-out region 23 shown is shown as dashed lines in the direction of the observer 9.The illustrated exemplary second embodiment of the display device according to the invention according to FIG. 1B differs from the embodiment according to FIG. 1A in that according to FIG. 1B the display surface 1 is designed to be reflective over its full surface, wherein the information of the display surface 1 to be reproduced via the display side 11 is projected onto the display side 11 of the display surface by a front-side projection device 8, as is illustrated in FIG. 1B by means of arrows with continuous lines. As illustrated, the projection device 8 can be arranged outside the actual display surface 1 and particularly preferably in a non-visible region for the observer 9. The projection devices 8 for projecting the information to be reproduced on the display surface 1 can be, for example, an LCD projector, an LCOS projector, an LBS projector or a DLP projector.As an alternative to the aforementioned projection devices 8, it can be provided that the display surface 1 is formed as an LCD panel, OLED panel or, for example, as an e-ink display. The information to be output via the display side 11 is not projected onto the display surface, but rather is generated in the display surface.FIG. 1C shows a third exemplary embodiment, wherein the display surface 1 is designed as an LCD panel and furthermore has a backlighting unit 5 on its rear side 12 for backlighting the LCD panel.FIG. 1D shows a further exemplary embodiment according to the invention, wherein the display surface 1 is designed as a self-illuminating OLED panel.As is shown in FIGS. 1D and 2A, the display devices according to the invention can furthermore have a transparent cover substrate layer 3, which is arranged in front of the light guide device 2 in the direction of the observer 9 and at least partially covers the light guide device 2.The cover substrate layer can of course be formed as a cover glass layer. Furthermore, it can be provided that the light guide device 2 and the display surface 1 and preferably the cover substrate layer 3 are laminated to one another.As is shown in FIGS. 2B and 3, the decoupling regions 23 of the light guide device 2 can be designed for displaying symbols 25, for example in the form of arrows or triangles.As is illustrated in FIG. 2, it can be provided that at least one associated light source 21 is associated with each decoupling region 23 of the light guide layer 20 in order to actively illuminate each decoupling region 23 via the respectively associated at least one light source 21.As shown centrally in FIG. 3, it can also be provided that a plurality of light sources 21 are provided for illuminating an decoupling region 23.As is shown in all the figures, it can preferably be provided that the at least one light source 21 of the light guide device 2 is arranged outside the region of the actual display surface 1 and wherein the at least one light source 21 preferably couples light generated by the light source 21 into the at least one light guide layer via at least one side surface 27 of the at least one light guide layer 20.As is schematically shown in FIGS. 2A and 2B, the light guide device 2 can be formed as a continuous light guide layer 20, which covers the entire display surface 1 in terms of area in the direction of the observer 9, and wherein a plurality of light guides 2 are formed by introducing recesses or cuts 29 into the light guide layer 20, wherein the light guides 2 are delimited from one another by the cuts or recesses 29, such that the coupled-in light cannot be exchanged between the various light guides 2 delimited from one another. In the figures, the light beams emitted by the light sources 21 are illustrated as dashed arrows.

Claims

Display device for a vehicle, having - a display surface (1) which has a display side (11) for reproducing information in the direction of a viewer (9) and a rear side (12) facing away from the latter; - a light guide device (2) having at least one light source (21); - wherein the light guide device (2) has at least one transparent light guide layer (20) which extends in front of the display side (11) and at least partially covers the display side (11), - wherein the at least one light guide layer (20) has at least one decoupling region (23) in at least one subarea region of the display side (11) for decoupling the light of the at least one light source (21) in the direction of the viewer (9), and - wherein the at least one decoupling region (23) is designed for superimposing the information reproduced via the display side (11) by the decoupled light.Display device according to Claim 1, wherein the display surface (1) is transmissive at least in a first subregion, and wherein the information of the display surface (1) to be reproduced is projected onto the rear side (12) of the display surface (1) by a rear projection device (8).Display device according to Claim 1 or 2, wherein the display surface (1) is reflective at least in a second subregion, and wherein the information of the display surface (1) to be reproduced is projected onto the display side (11) of the display surface (1) by a front-side projection device (8).Display device according to one of the preceding claims, wherein the display device (1) has a projection device (8) for projecting the information to be reproduced on the display surface (1), wherein the projection device (8) is selected from the group of an LCD projector, an LCOS projector, an LBS projector or a DLP projector.Display device according to one of the preceding claims, wherein the display device further comprises a transparent cover substrate layer (3) which is arranged in front of the light guide device (2) in the direction of the observer (9) and at least partially covers the light guide device (2).Display device according to one of the preceding claims, wherein the light guide device (2) and the display surface (1) and preferably the cover substrate layer (3) are laminated to one another.Display device according to one of the preceding claims, wherein the cover substrate layer (3) is formed as a cover glass layer.Display device according to one of the preceding claims, wherein the at least one decoupling region (23) is designed for displaying symbols (25).Display device according to one of the preceding claims, wherein the at least one light decoupling region (23) of the light guide device (2) is formed by the introduction of an optical microstructure into partial regions of the at least one light guide layer (20).Display device according to one of the preceding claims, wherein the at least one light decoupling region (23) of the light guide device (2) is formed by the introduction of an optical microstructure by means of nanoimprinting lithography.Display device according to one of the preceding claims, wherein the at least one decoupling region (23) is formed by forming a microstructure on the side of the light-conducting layer (20) facing the viewer (9) and facing away from the display surface (11).Display device according to one of the preceding claims, wherein the at least one decoupling region (23) is formed by introducing nanoparticles into the light guide layer (20) in the at least one decoupling region.The display device according to any preceding claim, wherein the at least one light guide layer (20) is formed of a PMMA or a PC sheet.Display device according to one of the preceding claims, wherein the at least one light source (21) has a defined light color, preferably a spectral color.Display device according to one of the preceding claims, wherein the at least one light source (21) has at least one RGB LED for active control of the light colour coupled into the at least one light guiding layer (20).Display device according to one of the preceding claims, wherein each decoupling region (23) of the light guide layer (20) is assigned at least one associated light source (21) in order to actively illuminate each decoupling region (23) via the respectively assigned at least one light source (21).Display device according to one of the preceding claims, wherein the display surface (1) is designed as an LCD panel and a backlighting unit (5) for backlighting the LCD panel is arranged on the rear side (12).Display device according to one of the preceding claims, wherein the display surface (1) is formed as an OLED panel.Display device according to one of the preceding claims, wherein the display area is designed as an e-ink display.Display device according to one of the preceding claims, wherein the at least one light source (21) of the light guide device (2) is arranged outside the region of the display surface (1) and wherein the at least one light source (21) preferably feeds light generated by the light source (21) via at least one side surface (27) of the at least one light guide layer (20) into the at least one light guide layer (20).Display device according to one of the preceding claims, wherein the light guide device (2) is formed as a continuous light guide layer (20), which covers the entire display surface (1) in terms of area in the direction of the observer (9), and wherein a plurality of light guides (2) are formed by introducing recesses or cuts (29) into the light guide layer (20), wherein the light guides (2) are delimited from one another by the cuts or recesses (29).Display device according to one of the preceding claims, wherein the microstructures introduced into the at least one light-guiding layer (20) are arranged in the surface plane of the light-guiding layer (20) in the form of a symbol (25).Display device according to one of the preceding claims, wherein the display surface (1) and the light guide device (2) are formed from an elastically deformable material.

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