Display device for vehicle

Abstract

The invention relates to a display device (18) for a vehicle, comprising a display screen (26) which has a display surface (40) which is backlit by scattered light, whereby the information can be seen. However, the display screen (26) is backlit in the region of the display surface (40) in which the one or more manual operating elements (22) are arranged by means of converged light, which is scattered at the front face (42) of each operating element (22) when exiting the display region (24). In this way, information in a display region (50) of the display surface (40), which is located behind the operating elements (22), can be seen without adversely affecting the front face (42) of the or each operating element (22).

Description

Technical Field

[0001] The invention relates to a display device for a vehicle and in particular to a display device for a vehicle in which a manually operable operating element is arranged on a display surface, for example in the form of a rotary controller or a rotary / push controller. Background Art

[0002] Display devices with the additional function of being able to input commands by touching the display surface, i.e. ultimately as a touchscreen, have proven themselves as a vehicle operating concept. However, over time it has become clear that inputting commands via a knob or a rotating / pressing actuator is sometimes more comfortable, ultimately depending on the specific application.

[0003] For this reason, people have already begun to arrange knobs or rotary / press regulators on touch screens in the past (see, for example, WO-A-2018 / 137944 or WO-A-2018 / 114138).

[0004] DE-A-10 2018 118 839 discloses a rotary / push controller on a backlit display, which is embodied as a ring within which the information displayed on the display can be seen.

[0005] DE-A-10 2015 015 308 describes an operating element with an integrated display, wherein the display is backlit by means of directional light.

[0006] If such an operating element arranged on the display surface of the display device is to have a display device itself, the display device is typically integrated into the operating element as an independent display unit. However, since the surface on which the operating element is arranged is itself designed as a display surface, the display surface can also be used directly as the display surface of the operating element in the area where the operating element is arranged. This means that the operating element has a "transparent" area through which the information on the display surface of the display screen can be seen.

[0007] However, it should be noted that the visible display surface of the operating element protrudes beyond the display surface of the display screen by the height of the operating element, so that the backlit alphanumeric or graphic information in the area where the operating element is located on the display surface of the display screen can be seen with reduced brightness in front of the operating element and is limited to a narrowed viewing angle range. Summary of the invention

[0008] The object of the present invention is to provide a display device for a vehicle, wherein an operating element is positioned on a display surface of a display screen, the operating element having a display area arranged at a distance from the display screen, in which alphanumeric or graphic information can be displayed with sufficient light intensity, the alphanumeric or graphic information being displayed on the display surface of the display screen.

[0009] In order to achieve the object, the present invention provides a display device for a vehicle, wherein the display device is provided with:

[0010] a display screen having a display surface for displaying (graphic and / or alphanumeric or other character) information,

[0011] - an operating element arranged on the display, which operating element can be operated manually,

[0012] wherein the operating element has a front face which is arranged at a distance from the display surface of the display screen and has at least one display area for displaying information in a display area of ​​the display surface of the display screen which is aligned with the display area of ​​the front wall of the operating element, and

[0013] - a backlight unit for backlighting the display screen,

[0014] wherein the backlight unit comprises a light guide plate, the light guide plate having a light emitting surface facing the display screen and a back surface facing away from the light emitting surface and a backlight light source for inputting backlight into the light guide plate,

[0015] wherein the light guide plate has a light-transmitting area for collimating light, which is arranged between its rear side and its light exit surface, and which is aligned with a display area in front of the operating element,

[0016] wherein the backlight unit further comprises at least one further light source for collimated light, the collimated light passing through the light-transmitting area of ​​the light guide plate and being emitted at the light exit surface of the light guide plate and, after passing through a display area of ​​the display surface of the display screen aligned with the display area of ​​the operating element, backlighting the information displayed in the area and making the information visible in the display area of ​​the operating element,

[0017] wherein a diffuser is arranged in the operating element between its display area and a display area of ​​the display surface of the display screen aligned with the display area for scattering the collimated light for the display area of ​​the operating element.

[0018] The display device according to the invention has a display screen with a display surface for displaying information, i.e., for example, graphic and / or alphanumeric information or character information. A manually operable operating element is arranged on the display screen, for example in the form of a knob, a rotary / push adjuster or one or more operating keys. The operating element itself has a front face arranged at a distance from the display surface of the display screen, at least one display area is located in the front face, in which information is displayed, which information can be seen in a display area of ​​the display surface of the display screen, with which the display area on the front face of the operating element is aligned (i.e., is located on a common optical axis).

[0019] The display screen is backlit by means of a backlight unit, which has a light guide plate or a light guide film, which has a light exit surface facing the display screen and a back side facing away from the light exit surface. In addition, the backlight light source that inputs the backlight into the light guide plate or the light guide film and, if necessary, a reflective layer on the back side of the light conductor, the light exit surface of the light conductor facing away from the back side, also belong to the backlight unit. The light guide plate (if the light conductor or light guide plate is mentioned below, this also means that the light conductor is designed as a film) has a light-transmitting area for collimating light between its back side and its light exit surface, wherein, according to the invention, the light-transmitting area is aligned with the display area on the front side of the operating element, that is, it is located on a common optical axis with the display area. The backlight unit is additionally provided with at least one other light source, which outputs collimated light differently from the aforementioned backlight light source, the collimated light passes through the light transmission area of ​​the light guide plate and is emitted at the light exit surface of the light guide plate, and after passing through the display area of ​​the display surface of the display screen aligned with the display area of ​​the operating element, backlights the information displayed in the area and makes the information visible in the display area of ​​the operating element, specifically, the collimated light is brighter than the backlight emitted from the light exit surface of the optical waveguide, even if the backlight is emitted from the light exit surface of the light guide plate within the light transmission area for the collimated light. In addition, in order to make the information visible there visible in the widest possible viewing angle range, a diffuser is provided in the operating element between its display area and the display area of ​​the display surface of the display screen aligned with the display area, for scattering the collimated light of the display area of ​​the operating element.

[0020] The light guide of the backlight unit according to the invention is not only used for large-area and uniform backlighting of the display surface of the display screen, but also the light guide plate is "illuminated" by collimated light in at least one light-transmitting area, whereby the collimated light is concentrated and focused more strongly than in the remaining areas of the display surface onto the following display area of ​​the display surface of the display screen and backlights it, which display area is aligned with the display area on the front side of the operating element and is thus on a common axis with the light-transmitting area of ​​the light guide plate. In order for the collimated light to now be emitted from the display area on the front side of the operating element again within a relatively large viewing angle range, a diffuser element is preferably present in the operating element close to the front side for scattering the collimated backlight for this display area.

[0021] The backlighting concept achieves that not only the display surface of the display outside the at least one operating element arranged on the display is backlit uniformly and brightly, but also the display area of ​​the at least one operating element arranged above the display surface of the display is backlit sufficiently strongly and can be seen over a wide viewing angle range.

[0022] As already mentioned above, the operating element can be designed as at least one button and / or at least one rotary adjuster and / or at least one rotary / press adjuster. Generally speaking, the operating element can have a structure for tactile feedback (passive or active). If the operating element is provided with an adjustable part, this adjustment can be carried out in a latching manner.

[0023] The at least one light source for collimated light expediently comprises at least one illuminant, in particular at least one LED, and a reflector and / or a lens.

[0024] The light-transmitting region of the light guide plate for collimating the light can expediently be designed as a through-hole of the optical waveguide or the light guide plate or as an integral component of the light guide plate.

[0025] In an advantageous design of the present invention, it can be provided that at least one light source for collimated light is arranged toward the back of the light guide plate and the light transmission area of ​​the light guide plate for collimated light. That is, the collimated light can enter the light transmission area of ​​the light guide plate like "direct backlight".

[0026] Alternatively, it can be provided that the light source for collimated light has at least one illuminant, in particular at least one LED, and a light conductor provided with a light exit end and a light entrance end, the light exit end being opposite to or arranged in the light transmission area of ​​the light guide plate for collimated light, and the light entrance end being arranged outside the back side of the light guide plate. That is, the light source or the light source for collimated light is projected into the light conductor, the light exit end of the light conductor being arranged in the through hole of the light guide plate or arranged opposite to the light transmission area of ​​the light guide plate.

[0027] The display scheme according to the present invention can also be implemented in multiple ways in a display device, so that this display device is provided with multiple operating elements and multiple display areas on the display surface respectively aligned with their display areas, and the multiple display areas are respectively assigned transparent areas for collimated light in the light guide plate of the backlight unit, wherein the backlight unit has at least one light source for collimated light for each transparent area or at least one light source common to all transparent areas for collimated light, and the optical conductor extends from the light source to the transparent area of ​​the light guide plate.

[0028] In a further expedient embodiment of the invention, it can be provided that at least one light source for the collimated light has a laser diode and in particular a red, green and blue laser diode arrangement.

[0029] Advantageously, the light source for the backlight is arranged opposite the rear side of the light guide plate and / or the side edge region of the light guide plate.

[0030] Typically, the backlight light sources are implemented as LEDs. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be described in detail below with reference to the accompanying drawings and with reference to the embodiments.

[0032] Figure 1 A view showing a dashboard of a vehicle having a display device according to the invention which also serves as an operating device,

[0033] Figure 2 Shown along the Figure 1 A cross-sectional view of the lower right region of the display device cut along line II-II shown in FIG.

[0034] Figure 3 An example for inputting a backlight for an area of ​​a display surface of a display screen in which no additional manual operating elements are located, and

[0035] Figures 4a to 4c Three examples of the structure of a light source for emitting substantially collimated or concentrated light for backlighting a display area of ​​a display surface of a display screen of a display device, in which a manual operating element designed as a rotary controller is arranged, are shown.

[0036] Figure 5 An example is shown for supplying red, green and blue collimated light into a region of the optical waveguide aligned with the manual operating element, in which the optical waveguide has its light-transmitting region for the collimated light. DETAILED DESCRIPTION

[0037] Figure 1The perspective view of the instrument panel 10 in the interior 12 of the vehicle 14 is shown, which in this embodiment is provided with an operating device 16 having a display device 18, which in this embodiment is designed as two manually operable operating elements 22 of rotary actuators 20. The two operating elements 22 have a display area 24, in which information (alphanumeric or graphic or other characters) displayed in the area of ​​the display device 18 below the operating elements 22 can be seen.

[0038] exist Figure 2 1 shows the components of the display device 18 that are mainly relevant to the present invention. Thus, the display device 18 has a display screen 26, typically in the form of an LCD display screen, with a touch screen 28 (optionally) as a touch sensing device, and a cover plate 30. A backlight unit 32 is used to backlight the display screen 26, the backlight unit having a light guide plate 34 with a light exit surface 36 facing the display screen 26 and a backlight light source 38. In this embodiment, the backlight light source 38 faces the back side 39 of the light guide plate 34.

[0039] The display surface 40 of the display device 18 is situated on the cover plate 30, on which the operating element 22 is arranged. This operating element is designed as a (hollow) ring 41, whose front end facing away from the display surface 40, i.e., the front face 42 of the operating element, has a display area 24, which is designed as a cover plate 46, wherein a diffuser 48 is located within the ring 41.

[0040] As if with Figure 2 As can be seen, the operating element 22 is located in a display area 50 of the display surface 40 of the display device 18, which is aligned with an area 52 of the light guide plate 34, wherein in the area 52 of the light guide plate 34, the light guide plate is provided with a light-transmitting area 54 for collimated light. The collimated light or, more generally, light 56 ​​which is concentrated compared to the backlight source 38 is Figure 2 4 and 5, which will be discussed later. In contrast, the backlight of the backlight light source 38 "diversifies" (indicated by arrow 57). Typically, there is also a diffuser layer for homogenizing the backlight between the light exit surface 36 of the light guide plate 34 and the display screen 26, and the diffuser layer should have a recess in the area aligned with the light-transmitting area 54, so that the collimated light is scattered by the diffuser 48 of the operating element 22 only after passing through the display screen 26.

[0041] The solution introduced here is characterized in that information in the display area 50 of the display surface 40 of the display device 18 is displayed in the display area 24 on the front 42 of the operating element 22 by means of concentrated light 56. Since the information is backlit by collimated or concentrated light from a collimated light source 58, the light is scattered by the diffuser 48 at the display area on the front, thereby making it possible to see the information that can be seen at the front 42 of the operating element 22 in a wide viewing angle range.

[0042] exist Figure 3 An alternative for backlighting a display surface 40 of a display device 18 is shown in FIG. In this exemplary embodiment, the backlighting is performed by a backlight source 38 which irradiates laterally into the display surface 40 of the display device 18. Figure 3 In the light guide plate 34 not shown in the figure. It should be noted here that the light-transmitting area 54 (for example, see Figure 2 ) may result in a shadow effect for the backlight incident from the side. However, the light guide plate 34 is typically lined with a reflective film on its back side, so that the backlight can eventually reach the so-called "shadow area" of the operating element 22 through internal reflection and reflection on the reflective film.

[0043] exist Figures 4a to 4c Three embodiments of the design of the collimated light source 58 are shown in FIG. Figure 4b As shown in FIG. 6 , a reflector 60 is provided. Alternatively, as Figure 4a As shown in FIG. 6 , a TIR lens 62 , ie a lens with total internal reflection, can be used. In both cases, the light of, for example, an LED light source 64 is emitted in a directionally directed manner.

[0044] Alternative basis Figure 4a and 4b The solution can also use an aspherical lens 66, such as Figure 4c Finally, a further variant of the design of the collimated light source 58 involves the use of a Fresnel lens.

[0045] Another possibility for backlighting display screen 26 in region 50 of display surface 40 where operating elements 22 are located is to use laser light sources (eg laser LEDs). The use of RGB lasers enables the display of volume holograms to visualize three-dimensional images.

[0046] Finally, the collimated light in the display area 50 of the display surface 40 of the display device 18 can also be achieved by a sub-pixel microlens arranged in the area. In this embodiment, it is not necessarily required that the collimated light is emitted in the area of ​​the light exit surface 36 of the light guide plate 34 that is on the common optical axis with the display area 50 of the display surface 40 of the display device 18.

[0047] Another possibility for inputting collimated light into the light-transmitting area 54 of the light guide plate 34 may involve the use of an optical waveguide whose ends are arranged opposite to a light-transmitting area 54 or multiple light-transmitting areas 54 of the light guide plate 34, or are inserted into a through hole of the light guide plate 34, wherein the light incident end of the optical waveguide receives collimated light from a collimated light source 58, and the optical waveguide is arranged at a distance and in particular not behind the light guide plate 34.

[0048] Figure 5 An embodiment of a light source 58' for collimated light is shown. Figure 5 The display device 18 is shown in the view of FIG. Figure 2 The same reference numerals are used as in FIG.

[0049] The light source 58' is designed as a collimated laser light source and three (eg semiconductor) laser light sources R, G, B with colored lasers. The light beams of the three laser light sources are directed in parallel through the optical element KS by dichroic mirrors DS1 and DS2 to achieve collimation and reduce speckle.

[0050] The display device according to the invention is characterized in that in areas of the display surface where no operating elements are present, the backlight is emitted in a relatively non-directional and thus scattered manner, as is customary in backlit display devices, whereas the backlight is emitted in a significantly more directional and thus concentrated manner in the area of ​​the display device occupied by the manual operating element or elements, so as to be scattered first by a diffuser arranged at a distance from the display surface, i.e. in front of the operating element or elements. This solution can be applied to display devices having one or more operating elements, wherein the operating elements can have different heights. The light guide plate can be designed in one piece; the light-transmitting area or areas can be composed of the same or different light-conducting material as the rest of the light guide plate.

[0051] List of Reference Numerals

[0052] 2 Examples

[0053] 10. Dashboard

[0054] 12. Internal Space

[0055] 14 Vehicles

[0056] 16 Operating device

[0057] 18 Display device

[0058] 20 Rotary adjuster

[0059] 22 Operating elements

[0060] 24 display area on the front of the operating element

[0061] 26 Display

[0062] 28 Touch screen

[0063] 30 Cover

[0064] 32 Backlight unit

[0065] 34 Light guide plate

[0066] 36 Light exit surface

[0067] 38 Backlight source

[0068] 39 Back side of light guide plate

[0069] 40 Display surface of the display

[0070] 41 Ring of operating element

[0071] 42 Front of the operating elements

[0072] 46 Cover

[0073] 48 Diffuser

[0074] 50 Display area on the display surface of the display screen

[0075] 52 Areas

[0076] 54 Translucent Area

[0077] 56 Converging Light

[0078] 58 Collimated light source

[0079] 58' Collimated Light Source

[0080] 60 Reflector

[0081] 62 TIR lens

[0082] 64 LED light source

[0083] 66 Aspheric lens

[0084] DS1 Mirror

[0085] DS2 Mirror

[0086] KSR Optics for Collimation and Speckle Reduction

[0087] B Laser

[0088] G Laser

[0089] R Laser.

Claims

1. A display device for a vehicle, comprising: - a display screen (26) having a display surface (40) for displaying information, an operating element (22) arranged on the display screen (26), which operating element can be operated manually, -in, The operating element (22) has a front face (42) arranged at a distance from a display surface (40) of the display screen (26), the front face having at least one display area (24) for displaying information in a display area (50) of the display surface (40) of the display screen (26) aligned with the display area (24) of the front wall of the operating element (22); and - a backlight unit (32) for backlighting the display screen (26), - wherein the backlight unit (32) comprises a light guide plate (34), the light guide plate having a light emitting surface (36) facing the display screen (26), a back surface (39) facing away from the light emitting surface, and a backlight light source (38) inputting backlight into the light guide plate (34), wherein the light guide plate (34) has a light-transmitting area (54) for collimating light, arranged between its rear side (39) and its light exit surface (36), the light-transmitting area being aligned with the display area (24) of the front side (42) of the operating element (22), - wherein the backlight unit (32) further comprises at least one additional light source for collimated light, the collimated light passing through the light-transmitting area (54) of the light guide plate (34) and being emitted at the light exit surface (36) of the light guide plate (34) and, after passing through a display area (50) of the display surface (40) of the display screen (26) aligned with the display area (24) of the operating element (22), backlighting the information displayed in the area and making the information visible in the display area (24) of the operating element (22), - wherein a diffuser (48) is arranged in the operating element (22) between its display area (24) and a display area (50) of the display surface (40) of the display screen (26) aligned with the display area, for scattering collimated light for the display area (24) of the operating element (22).

2. The display device according to claim 1, characterized in that The operating element (22) is designed as at least one button and / or at least one rotary controller (20) and / or at least one rotary / push controller.

3. The display device according to claim 1 or 2, characterized in that: At least one light source for collimated light has at least one illuminant, in particular at least one LED, and a reflector (60) and / or a lens (62).

4. The display device according to any one of claims 1 to 3, characterized in that: The light-transmitting area (54) of the light guide plate (34) for collimating light is designed as a light conductor or a through hole of the light guide plate (34).

5. The display device according to any one of claims 1 to 4, characterized in that: At least one light source for collimating light is arranged toward the back side (39) of the light guide plate (34) and the light-transmitting area (54) for collimating light of the light guide plate (34).

6. The display device according to any one of claims 1 or 2, characterized in that: The light source for collimated light comprises at least one illuminant, in particular at least one LED, and an optical conductor provided with a light emitting end and a light incident end, the light emitting end being opposite to a light-transmitting area (54) for collimated light of the light guide plate (34) or being arranged in the light-transmitting area (54) for collimated light of the light guide plate (34), and the light incident end being arranged outside the back side (39) of the light guide plate (34).

7. The display device according to claim 6, characterized in that: A plurality of operating elements (22) and a plurality of display areas (50) on a display surface (40) of the display screen (26) respectively aligned with the display areas (24) thereof, wherein light-transmitting areas (54) for collimated light are respectively allocated to the plurality of display areas in a light guide plate (34) of the backlight unit (32), wherein the backlight unit (32) has at least one light source for collimated light for each light-transmitting area (54) or at least one light source common to all light-transmitting areas (54) for collimated light, and an optical conductor extends from the light source to the light-transmitting area (54) of the light guide plate (34).

8. The display device according to any one of claims 1 to 7, characterized in that: At least one light source for collimated light (58) has a laser diode and in particular a red, green and blue laser diode assembly.

9. The display device according to any one of claims 1 to 8, characterized in that: The light source is arranged opposite to the back side of the light guide plate (34) and / or the side edge region of the light guide plate (34).

10. The display device according to any one of claims 1 to 9, characterized in that: The backlight source (38) comprises an LED.

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