Display device having an ir camera for a vehicle
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-05-29
- Publication Date
- 2026-04-08
AI Technical Summary
The challenge is to integrate an IR camera into a vehicle display device without compromising the optical and lighting layers, as existing solutions often require separate stacks for the IR camera and display, which is undesirable and can lead to uneven backlighting and interference with IR radiation.
The solution involves a display device with a backlighting unit that includes reflectors and light sources for direct emission, a diffuser layer with a recess for a light guide plate, and an IR camera aligned with the light guide plate, ensuring homogenized backlighting and unhindered IR radiation transmission.
This configuration ensures improved illumination and unobstructed IR radiation capture, addressing the issue of uneven backlighting and interference, while maintaining a compact design by aligning the IR camera with the light guide plate and using a diffuser layer with reduced diffuser properties in the edge region.
Smart Images
Figure EP2024064762_05122024_PF_FP_ABST
Abstract
Description
Display device with IR camera for a vehicle
[0001] The invention relates to a display device with an IR camera for a vehicle and in particular to a display device in which the IR camera is arranged behind the display surface of the display or, in other words, behind that surface of the display device which is enclosed by a frame which typically surrounds the display.
[0002] To increase vehicle safety, it has long been known to monitor the vehicle interior for potential safety risks. In particular, it is known to capture the driver's face, for example, based on eyelid movement, to detect possible driver fatigue early on and then issue an appropriate alarm signal.
[0003] For various reasons, the cameras used for this purpose should be integrated into displays installed in the instrument panel. The frame that typically surrounds the display is generally the ideal location for accommodating the cameras in such displays. However, for aesthetic reasons, the trend is increasingly toward making these frames as narrow as possible, so that there is no longer enough space in this area to accommodate the camera. The same applies to the edge of the display itself, which is typically colored black near the display surface.
[0004] It is known, for example, to arrange IR cameras behind the display and behind its backlight unit. An example of such a concept is described in EP-A-3 608 147. However, this known system uses two different stacks of "optical films" for the IR camera and the actual display surface, which can be undesirable.
[0005] Various display devices with IR cameras are known from DE-A-10 2019 212 306, DE-A-10 2017 217 193, DE-A-10 2017 217 916 and DE-A-10 2020 129 547. Backlight units for displays are described, for example, in DE-A-10 2017 217 916 and DE-A-10 2020 202 917.
[0006] The object of the invention is to provide a display device with an IR camera for a vehicle, in which the structure and arrangement of the individual optical and opto-electronic as well as illumination layers are the same for both the area of the display surface and for the IR camera.
[0007] To achieve this object, the invention proposes, according to a first variant, a display device with an IR camera for a vehicle, wherein the display device is provided with - an electro-optical display having a front side with a display surface and a back side, - a backlight unit facing the back of the display for emitting visible backlight light to backlight the display, - wherein the backlight unit comprises reflectors and backlight light sources for direct radiation of the backlight light towards the back of the display, - one or more IR light sources for emitting IR light, e.g. through the display into an area in front of the display surface, - a first diffuser layer arranged between the backlight unit and the display and having a peripheral outer edge, - wherein the first diffuser layer has a recess open to a portion of its outer edge, in which or with which a light guide plate is arranged in alignment, - wherein the light guide plate has a light entry edge exposed to the outer edge of the first diffuser layer and a light exit side facing the back of the display, and - wherein the backlighting unit has further light sources for emitting visible light into the exposed light entry edge of the light guide plate, which light exits from the light exit side of the light guide plate to backlight the display, and - an IR camera that is arranged within the backlight unit in alignment with the light guide plate.
[0008] In this first variant of the invention, a direct backlighting unit is used for the display, in which the light sources emit their light directly toward the display. Typically, such backlighting concepts require a diffuser layer between the backlighting unit and the display. So-called BEF or DBEF layers can also be provided between the backlighting unit and the display.
[0009] While the diffuser layer in particular ensures scattering and thus homogenization of the backlit light and thus improved illumination of the display, such a measure is somewhat disadvantageous if, as provided by the invention, an IR camera is arranged behind or below the display, which receives the IR light emitted by the display device after reflection in the area in front of the display surface. This is because the received IR radiation is also negatively affected by the diffuser layer.
[0010] According to the first variant of the invention, it is therefore provided to arrange the IR camera with its optical axis aligned with an edge recess of the diffuser layer. However, this would mean that backlight light penetrating this edge recess would no longer be scattered or would be scattered in the area connected to this recess. aligned display area would have a different backlight intensity than the rest of the display area.
[0011] According to the invention, the recess is now filled with a light guide plate, which is supplied with backlighting according to the Edge Lit system. This backlighting then reaches the display through the side of the light guide plate facing the display, i.e., via its light exit side. This ensures homogeneous backlighting of the display, even in the area of the recess. Like the display, the light guide plate is permeable to IR radiation, so that IR radiation reflected from the area in front of the display surface reaches the IR camera unhindered.
[0012] The backlighting unit therefore has two types of light sources (typically in the form of LEDs) emitting light in the visible wavelength range: on the one hand, the direct-radiating light sources and the other light sources that enter the light guide plate via the light entry edge and exit via the light exit side.
[0013] According to a second variant of the invention, a display device of an IR camera for a vehicle is proposed, wherein the display device is provided with - an electro-optical display having a front side with a display surface and a back side, - a backlight unit facing the back of the display for emitting visible backlight light to backlight the display, - wherein the backlight unit comprises reflectors and backlight light sources for direct radiation of the backlight light towards the back of the display, - one or more IR light sources for emitting IR light into an area in front of the display surface, - a first diffuser layer arranged between the backlight unit and the display and having a peripheral outer edge, - wherein the first diffuser layer has light-refracting and / or light-deflecting light distribution homogenization properties on its top and / or bottom side in the form of prints and / or surface structures and / or has light-refracting and / or light-deflecting light distribution homogenization properties within the first diffuser layer, - wherein these light distribution homogenization properties gradually decrease within an outer edge region extending to the outer edge of the first diffuser layer, and in the outer edge region, a partial region with an exposed outer edge section is free or almost free of these light distribution homogenization properties, - wherein the backlighting unit has further light sources for emitting visible light into the exposed outer edge section of the partial area of the outer edge area, which is provided for backlighting the display with light emerging from the upper side of the diffuser layer located in the partial area of the outer edge area, and - an IR camera that is arranged within the backlight unit in alignment with the part of the outer edge area.
[0014] In this second variant, the area of the first diffuser layer freed from diffusion properties is formed as an integral part of the first diffuser layer. The zone of the first diffuser layer essentially freed from diffusion properties is realized by the light distribution homogenization properties used in the form of prints and / or surface structures and / or light-refracting and / or light-deflecting particles located within the first diffuser layer gradually decreasing in density towards said zone of the first diffuser layer. The area of the first diffuser layer that is aligned with the IR camera and the Accordingly, the first diffuser layer is designed to transmit IR radiation without scattering, and therefore exhibits no or essentially no light-refracting and / or light-deflecting light-distribution homogenization properties in the form of prints and / or surface structures and / or particles. These light-distribution homogenization properties gradually increase toward the remaining area of the first diffuser layer.
[0015] Typically, the light guide plate should be designed to be light-reflective on its side surfaces adjacent to the diffuser layer, for example by having reflector layers.
[0016] According to a third variant of the invention, a display device with an IR camera for a vehicle is proposed, wherein the display device is provided with - an electro-optical display having a front side with a display surface and a back side, - a backlight unit facing the back of the display for emitting visible backlight light to backlight the display, - wherein the backlight unit comprises reflectors and backlight light sources for direct radiation of the backlight light towards the back of the display, - one or more IR light sources for emitting IR light, e.g. through the display into an area in front of the display surface, - a first diffuser layer arranged between the backlight unit and the display and having a peripheral outer edge, - wherein the first diffuser layer has a recess in which or with which a light guide plate is arranged in alignment with a light exit side facing the rear side of the display and a light entry side facing away from this for receiving visible light from light sources of the backlighting unit, and an IR camera that is arranged within the backlight unit in alignment with the light guide plate.
[0017] In this third variant of the invention, the recess of the diffuser layer is expediently located within the diffuser layer and surrounded by the material of the diffuser layer. The recess is thus spaced from the outer edge of the diffuser layer on all sides. A light guide plate is located within the recess, which is arranged on the optical axis of the IR camera. The underside of the light guide plate, facing away from the display, forms its light entry side and receives visible light from light sources of the backlighting unit. This light emerges through the light guide plate, distributed from its light exit side.
[0018] In this variant of the invention, light sources of the backlighting unit are used to feed the light guide plate with their optical axes pointing directly toward the display. The light guide plate is transparent to IR radiation, so that reflected IR radiation from the area in front of the display surface reaches the IR camera essentially unhindered.
[0019] In this third variant of the invention, the light guide plate has light-reflecting side surfaces adjacent to the diffuser layer for reflecting light radiated into the light guide plate by the other light sources.
[0020] As mentioned above, the light from the backlight unit can be fed into the light guide plate by the backlight unit's light sources, which radiate directly toward the display. These light sources are advantageously arranged at an angle. They are conveniently located around the camera and illuminate the light guide plate from below.
[0021] Alternatively, it is possible for the light guide plate to have light guide projections pointing downward toward the light sources of the backlighting unit, with at least one such light guide projection being sufficient. The light guide projection can be designed in the form of a ring structure and has a light entry side facing away from the light guide plate, which in turn is opposite one or more light sources of the backlighting unit that emit visible light.
[0022] According to a fourth variant of the invention, a display device with an IR camera for a vehicle is proposed, wherein the display device is provided with - an electro-optical display having a front side with a display surface and a rear side (18), - a backlight unit facing the back of the display for emitting visible backlight light to backlight the display - wherein the backlight unit comprises reflectors and backlight light sources for direct radiation of the backlight light towards the back of the display, - one or more IR light sources for emitting IR light into an area (36) in front of the display surface of the display, - a first diffuser layer arranged between the backlight unit and the display, - wherein the first diffuser layer has light-refracting and / or light-deflecting light distribution homogenization properties on its top and / or bottom side in the form of prints and / or surface structures and / or has light-refracting and / or light-deflecting light distribution homogenization properties within the first diffuser layer, - wherein said light distribution homogenization properties gradually decrease within an inner region of the first diffuser layer and in a region within this region part of the area is free or almost free of these light distribution homogenization properties, - wherein light sources of the backlighting unit are arranged in alignment with the partial area, and - an IR camera that is arranged within the backlight unit in alignment with the part of the outer edge area.
[0023] In this fourth variant of the display device according to the invention, the region of the first diffuser layer which is essentially free of diffuser properties is not located in the edge region of the first diffuser layer but rather within this diffuser layer, and is therefore surrounded on all sides by regions of the first diffuser layer with diffuser properties.
[0024] In the fourth variant of the invention, the region of the first diffuser layer which is essentially free of light distribution homogenization properties is achieved in the same way as in the second variant by gradually decreasing the density of prints, surface structures or particles which provide corresponding light distribution homogenization properties.
[0025] According to a fifth variant of the invention, this proposes a display device with an IR camera for a vehicle, wherein the display device is provided with - an electro-optical display having a front side with a display surface and a back side, - a backlight unit facing the back of the display for emitting visible backlight light to backlight the display, - wherein the backlight unit comprises reflectors and backlight light sources for direct radiation of the backlight light towards the back of the display, - one or more IR light sources for emitting IR light, e.g. through the display into an area in front of the display surface, - a first diffuser layer arranged between the backlight unit and the display and having a peripheral outer edge, - wherein the first diffuser layer has a recess in which a carrier layer with OLEDs and / or micro-LEDs is arranged for emitting visible backlight light in the direction of the display, and - an IR camera that is arranged within the backlight unit in alignment with the light guide plate.
[0026] In this variant of the invention, the recess in the diffuser layer is filled by a carrier layer with OLEDs and / or micro-LEDs, which in turn emit light directly towards the back of the display.
[0027] Regarding the design of the backlighting unit, it can advantageously be provided that, in addition to the light sources radiating directly toward the back of the display, it also has reflectors. Both the light sources and any reflectors present are typically arranged in a 2D matrix structure. Within each reflector there is at least one light source for visible light. Such backlighting units are also referred to as matrix direct backlight units.
[0028] In addition to the above, the backlighting unit can also be designed with a light dimming function for selectively dimming the backlight light locally, as described in WO-A-2022 / 029239. The content of this document is hereby incorporated by reference into the present disclosure.
[0029] For all of the aforementioned variants of the display device according to the invention, in addition to the diffuser layer with its recess, an optical brightness enhancement layer and / or an optical transreflective polarization layer can be arranged between the display and the backlighting unit, which in turn have recesses aligned with the recess of the first diffuser layer. Suitable additional layers are optical layers particularly known for displays with backlighting light radiating directly onto their rear side, such as a brightness enhancement layer (also known in the art as BEF, which is an acronym for the name of a commercially available optical film) or a transreflective polarization layer (known in the art as DBEF, which is also an acronym for the name of a commercially available optical film).
[0030] In a last variant of the invention, a display device with an IR camera for a vehicle is proposed to achieve the above-mentioned object, wherein the display device is provided with - an electro-optical display having a front side with a display surface and a back side, - a backlight unit facing the back of the display for emitting visible backlight light to backlight the display, - wherein the backlight unit comprises reflectors and backlight light sources for direct radiation of the backlight light towards the back of the display, - one or more IR light sources for emitting IR light through the display into an area in front of the display surface, - a first diffuser layer arranged between the backlight unit and the display and having a peripheral outer edge, and an IR camera located in one of the reflectors of the backlight unit.
[0031] In this sixth variant of the invention, a micro-IR camera is used, which is typically arranged together with at least one light source of the backlighting unit within one of the reflectors of the backlighting unit.
[0032] This sixth variant of the invention can advantageously have a structure of the first diffuser layer as described above in connection with the first to fifth variants. All configurations of the first diffuser layer as described above are thus possible for use in the display device according to the sixth variant.
[0033] In a further expedient embodiment of the invention according to each of the aforementioned variants, the display device can have a first mirror reflection polarization film arranged on the back of the display or opposite thereto for reflecting visible backlighting light, the polarization of which deviates from the polarization direction of a rear polarization filter of the display, wherein backlighting light reflected by the first mirror reflection polarization film can be reflected by the reflectors of the backlighting unit back towards the first mirror reflection polarization film, changing its polarization direction.
[0034] As mentioned above, such mirror-reflective polarization filters are known under the keywords BEF (Brightness Enhancement Film), DBEF (Dual Brightness Enhancement Film), and ALCF (Advanced Light Control Film) as optical films or coatings from, for example, 3M. All of these systems or components ensure an increase in the light output for the display's backlight.
[0035] In a further advantageous embodiment of the invention, it can be provided that the first mirror reflection polarization film also reflects IR light whose polarization deviates from the polarization direction of the rear polarization filter of the display, and that an IR reflection film is arranged below the IR light sources for reflecting IR light reflected by the first mirror reflection polarization film while changing the polarization direction.
[0036] A further embodiment of the invention is characterized by a second mirror reflection polarization film arranged below the backlight unit for reflecting IR light whose polarization deviates from the polarization direction of a rear polarization filter of the display, and an IR reflection film arranged below the IR light sources for reflecting IR light reflected by the second mirror reflection polarization film while changing the polarization direction.
[0037] Typically, IR light sources emit NIR light, so the IR camera is a NIR camera. The IR camera is either a two-dimensional or line-scan camera and can be equipped with an optical lens.
[0038] The display surface can also advantageously be used for entering commands by touching the display surface if a touch sensor is integrated accordingly, such as can be realized by a touch panel.
[0039] As already explained above, the IR light sources are also conveniently integrated into the backlighting unit. They also radiate their IR light directly toward the display and are positioned, for example, below the recess in the diffuser layer. However, it would also be possible to position the IR light sources near the edge of the display or below and / or within its typically present bezel.
[0040] In addition to the first diffuser layer and the optionally present further optical layers already mentioned above, the display device according to the invention can, according to the variants with a recess in the first diffuser layer, also have a further (second) diffuser layer, which likewise has a recess, which in turn is aligned with the recess of the first diffuser layer or with the recesses of the optionally optical layers, wherein the recess of this further diffuser layer covers the transition from the light guide plate to the first diffuser layer with its edge region.
[0041] In the case of backlighting units with light sources radiating light directly from the rear, the problem sometimes arises that this directly radiated light can only be inadequately homogenized with just one diffuser layer. Therefore, approaches already exist in the prior art to use multiple diffuser layers or "thicker" diffuser layers. An advantage of using multiple diffuser layers (for example, using two diffuser layers) is that, in addition to the first diffuser layer according to the invention, a further diffuser layer is used that is neutral, i.e., transparent, to IR radiation. Such diffuser layers are described, for example, in US-A 2022 / 0091316. There, the said IR-neutral diffuser layer is described as a "High Infrared Light Clarity Diffuser."
[0042] In a further advantageous embodiment of the invention, the at least one IR light source can be arranged outside the display area, for example within a frame surrounding the display. Alternatively, the at least one IR light source can also be arranged below the diffuser layer, below the backlighting unit. An arrangement of the at least one IR light source within the backlighting unit is also possible. Finally, if the at least one IR light source is not arranged outside the display area, it can be illuminated with diffuser properties, ie Light distribution homogenization properties in the essentially free zone of the first diffuser layer are arranged in alignment.
[0043] The invention is explained in more detail below using various embodiments and with reference to the drawings. In detail: Fig. 1 is a schematic side view of the main components of a first embodiment of a display device essential to the invention, Fig. 2 is a plan view of the display device according to Fig. 1 in the direction of arrow II, Fig. 3 is a schematic side view of the main components of a second embodiment of a display device that are essential to the invention, Fig. 4 is a schematic side view of the main components of a third embodiment of a display device essential to the invention, Fig. 5 is a plan view of the display device according to Fig. 3 or Fig. 4 or Fig. 6 in the direction of arrow II, Fig. 6 is a schematic side view of the main components of a fourth embodiment of a display device essential to the invention, Fig. 7 is a schematic side view of the main components of a further embodiment of a display device which are essential to the invention, and Fig. 8 is a plan view of the reflector of the backlighting unit of the embodiment according to Fig. 7, in which, in addition to at least one light source, the IR camera is also arranged in the form of a mini-camera. Fig. 9 two views (side and sectional views) of a further and 10 embodiment in which the area of the diffuser layer substantially freed from light distribution homogenization properties is formed integrally therewith and thus, unlike the remaining area of the diffuser layer, has no light distribution homogenization properties, and Fig. 11 shows three variants of a first diffuser layer with light diffusion properties gradually decreasing towards the part area free or almost free of light distribution homogenization properties.
[0044] The figures show several exemplary embodiments of a display device according to the invention. Where the individual exemplary embodiments contain elements of the same design or function, they are provided with the same reference numerals in the figures.
[0045] Fig. 1 shows a first embodiment of a display device 10a with an IR camera. The display device 10a has a backlit display 12 based, for example, on LC technology, which has a front side 14 with a display surface 16 and a rear side 18. Facing the rear side 18 is an optical stack 20, which has at least a first diffuser layer 22. Typically, the optical stack 20 is provided with further optical layers, such as a BEF layer (Brightness Enhancement Film) and / or a DBEF layer and / or a DLRP layer (Direct Light Reflective Polarizer). Such optical layers for optimizing the backlighting of LC displays by backlight light sources radiating directly toward the LC display 12 are known in the prior art. basically known, which is why reference is made to these known layers.
[0046] Below the optical stack 20 is a backlighting unit 24, which has a carrier element 26 in the form of, for example, a circuit board, on which backlighting light sources 28, typically in the form of LEDs, and reflectors 30 are arranged. An IR camera 32 is also located on the carrier element 26. Furthermore, IR light sources 34 can also be located on the carrier element 26.
[0047] IR light is now emitted into the area 36 in front of the display surface 16 through the optical stack 20 and through the display 12 (the latter when the IR light sources 34 are arranged below the display 12). If an object, such as the face of a person looking at the display device 10a, is located in this area, the IR light is reflected and reaches the IR camera 32. If the reflected light had to pass through the optical stack 20, there would be a risk of falsification of the IR light, so that the IR camera 32 would only capture inferior camera images.
[0048] Therefore, the optical stack 20 according to the first to fourth exemplary embodiments (Figs. 1 to 8) is provided with a through-opening 38, which is represented, for example, as a recess 40 in the first diffuser layer 22. This recess 40 is shown in Fig. 2 as an edge recess of the first diffuser layer 22. The first diffuser layer 22 has a circumferential boundary edge 42, which is formed within one of its sections by the (light entry) edge 43 of a light guide plate 44 exposed within this section. The light guide plate 44 has the task of providing backlighting for the display 12 within the through-opening 38 of the optical stack 20.For this purpose, the backlighting to be realized in this area is carried out by further light sources 46 for visible light arranged laterally to the said light entry edge 43 of the light guide plate 44, which radiate their light into the light entry edge 43 opposite them, wherein this light is passed through the. Light exit side 48 of the light guide plate 44 and thus from the top side 23 in the direction of the display 12. Unlike the optical elements of the optical stack 20, the light guide plate 44 does not distort reflected IR light coming from the area 36, so that the IR camera 32 arranged in alignment with the light guide plate 44 receives the reflected IR light unadulterated or essentially unadulterated.
[0049] The light guide plate 44 can be designed to reflect light in its side surfaces 50 adjacent to the first diffuser layer 22.
[0050] Fig. 2 shows, by way of example, the positions within the display device 10a where the IR light sources 34 can be arranged. A first variant of the arrangement of these IR light sources is that they are positioned outside the optical stack 20, for example, in the edge region 52 and thus within a frame 54 of the display device 10a. Alternatively, as already described above, they can be part of the backlighting unit 24, wherein they can be arranged either below the optical stack 20 or below the light guide plate 44.
[0051] The optical stack 20 expediently has a further diffuser layer 56, which also has a recess 58, which, in its edge region, covers the transition 60 of the light guide plate 44 to the first diffuser layer 22 or to the optical stack 20. This is indicated in Fig. 1.
[0052] The display device 10b according to Fig. 3 differs from the embodiment according to Fig. 1 in that the light guide plate 44 is now illuminated from below, i.e. not from the edge, by visible light emitting light sources 28 of the support element 26. For this purpose, the light guide plate 44 can advantageously have light guide projections 64 on its underside light entry side 62, the light entry side or sides 66 of which light sources 28 for visible light which exits via the light exit side 48 of the light guide plate 44 in the direction of the display 12. The IR camera 32 is located below the light guide plate 44.
[0053] In the embodiment of the display device 10c of Fig. 4, the illumination of the light guide plate 44 is effected by light sources 28 of the carrier element 26 which are advantageously slightly inclined for this purpose.
[0054] In both the embodiment of Fig. 3 and that of Fig. 4, the recess in the optical stack 20 can be surrounded on all sides by material from the layers of the optical stack 20. This is because there is no edge-lit illumination of the light guide plate 44 with backlighting light, as is the case in the embodiment of Figs. 1 and 2.
[0055] Fig. 6 shows a further exemplary embodiment of a display device 10d according to the invention, in which a carrier element 67 provided with OLEDs or micro-LEDs (neither shown) is arranged in the through-opening 38 in the optical stack 20. Transparency for IR light through the carrier element 67 with the OLEDs or micro-LEDs is ensured, so that here too the IR camera 32, which is located below this carrier element 67 on the carrier element 26 of the backlighting unit 24 (which also applies to all other exemplary embodiments of the display device according to the invention, as also shown in the figures), receives reflected IR light essentially undisturbed.
[0056] Figs. 7 and 8 show an additional embodiment of a display device 10e according to the invention. The optical stack 20 between the backlight unit 24 and the display 12 has no through-opening in this embodiment. The IR camera 32 is located together with one or more light sources 28 of the carrier element 26 within a reflector 30. This is shown in Fig. 8. Alternatively, the optical stack 20 can also have the configuration according to one of the previous or subsequently described embodiments.
[0057] A further embodiment of the invention is shown in Figs. 9 and 10. The structure of the display device 10f shown in these figures is similar to that of the display device 10a in Figs. 1 and 2, so that the reference numerals used there are essentially the same in Figs. 9 and 10.
[0058] The difference between the display device 10F and that of Figs. 1 and 2 can be seen in the structure of the first diffuser layer 22'. This diffuser layer 22' has light diffusion properties, ie, light distribution homogenization properties in the form of light-refracting and / or light-deflecting properties, which can be realized, for example, in the form of a print on the plastic layer, a surface structure of the plastic layer, and / or in the form of particles within the plastic layer.
[0059] In one region, the diffuser layer 22' exhibits no or essentially no such light-refracting or light-deflecting properties, and is thus "neutral" for reflected IR light in particular. This partial region is designated by reference numeral 44' in Figs. 9 and 10. In this exemplary embodiment, it is located in an outer edge region 45, which, within the boundary edge 42 of the first diffuser layer 22', has an exposed outer edge section 43' as a light entry edge for the partial region 44'. As in the exemplary embodiment of the display device 10a, the backlighting light from the (edge-lit) light sources 46 of the backlighting unit 24 now radiates into this light entry edge of the partial region 44'.
[0060] The partial area 44' that is free or essentially free of light diffusion properties is formed by the light diffusion properties gradually decreasing from the remaining area of the first diffuser layer 22'. This is indicated in Figures 9 and 10 at 47', in that It is graphically shown that the density of the points, which are intended to represent the degree of light diffusion properties, gradually decreases until finally in the partial area 44' no light diffusion properties exist anymore or essentially no light diffusion properties exist anymore.
[0061] The advantage of the design of the diffuser layer 22 according to Figs. 9 and 10 is the simpler construction and assembly of the display device.
[0062] Figures 11 to 13 show various possibilities for influencing the degree of light diffusion properties of the first diffuser layer 22'.
[0063] According to Fig. 11, the light diffusion properties of the first diffuser layer 22 are achieved by particles within the diffuser layer 22'. By gradually decreasing the particle density toward the partial region 44' and by eliminating or not providing such particles in the partial region 44', this partial region 44' can ultimately be designed free of light diffusion properties.
[0064] Fig. 12 shows an example in which the volume of the first diffuser layer 22' is free of light-refracting or light-deflecting particles throughout the entire region in which the gradual decrease in light diffusion properties occurs, including the partial region 44'. The gradual decrease outside the partial region 44', which borders this partial region 44', is achieved by a gradually decreasing density of the printing on the surface (top and bottom) of the diffuser layer 22' or by a gradual decrease in the density of any additional light-refracting or light-deflecting surface structures of the first diffuser layer 22'.
[0065] Finally, Fig. 13 shows that the light diffusion properties of the first diffuser layer 22' can be adjusted by printing or The surface structure is applied in those areas where the light diffusion properties are desired. Towards sub-area 44', there is a gradually decreasing density of printing or surface structure in area 47'. LIST OF REFERENCE SYMBOLS 10a Display device 10b Display device 10c Display device 10d Display device 10e Display device 10f Display device 12 Display 14 Front of the display 16 Display surface of the display 18 Back of the display 20 Optical stack 22 First diffuser layer of the optical stack 22' First diffuser layer of the optical stack 23 Top side of the first diffuser layer 23' Top side of the first diffuser layer 24 Backlight unit 26 Carrier element (printed circuit board) of the backlight unit 28 Backlight light sources 30 Reflectors of the backlight unit 32 IR camera 34 IR light sources 36 Area in front of the display 38 Through opening in the optical stack 40 Recess in the first diffuser layer 42 Boundary edge of the first diffuser layer or of the optical stack 43 Light entry edge of the light guide plate 43' Outer edge section as light entry edge for the partial area which is essentially is free of light diffusion properties 44 Light guide plate 44' portion of the first diffuser layer, substantially free of light diffusion properties 45 outer edge area with sub-area 44' additional light sources of the backlight unit Light exit side Side surfaces of the light guide plate Edge area of the display device Frame of the display additional diffuser layer Recess of the further diffuser layer Transition of the light guide plate to the first diffuser layer or to the optical Stack underside light entry side Fiber optic projection Light entry side of the light guide projection Carrier element with OLEDs or micro-LEDs
Claims
CLAIMS 1. A display device with an IR camera for a vehicle, comprising an electro-optical display (12) having a front side (14) with a display surface (16) and a rear side (18), a backlighting unit (24) facing the rear side (18) of the display (12) for emitting visible backlighting light for backlighting the display (12), wherein the backlighting unit (24) has reflectors (30) and backlighting light sources (28) for directly emitting the backlighting light toward the rear side (18) of the display (12), one or more IR light sources (34) for emitting IR light into an area (36) in front of the display surface (16) of the display (12), a first diffuser layer (22) arranged between the backlighting unit (24) and the display (12) and having a circumferential outer edge (42), wherein the first diffuser layer (22) has a recess (40) open to a portion of its outer edge (42),in which or with which a light guide plate (44) is arranged in alignment, wherein the light guide plate (44) has a light entry edge (43) exposed to the outer edge of the first diffuser layer (22) and a light exit side (48) facing the rear side (18) of the display (12), and wherein the backlighting unit (24) has further light sources (46) for emitting visible light into the exposed light entry edge (43) of the light guide plate (44), which light exits from the light exit side (48) of the light guide plate (44) for backlighting the display (12), and an IR camera (32) arranged within the backlighting unit (24) in alignment with the light guide plate (44).
2. Display device with IR camera for a vehicle, with an electro-optical display (12) having a front side (14) with a display surface (16) and a rear side (18), a backlighting unit (24) facing the rear side (18) of the display (12) for emitting visible backlighting light for backlighting the display (12), wherein the backlighting unit (24) has reflectors (30) and backlighting light sources (28) for directly emitting the backlighting light toward the rear side (18) of the display (12), one or more IR light sources (34) for emitting IR light into an area (36) in front of the display surface (16) of the display (12), a first diffuser layer (22) arranged between the backlighting unit (24) and the display (12), wherein the first diffuser layer (22) has a recess (40),in which or with which a light guide plate (44) is arranged in alignment with a light exit side (48) facing the rear side (18) of the display (12) and a light entry side (62) facing away from this for receiving visible light from light sources (28) of the backlighting unit (24), and an IR camera (32) which is arranged within the backlighting unit (24) in alignment with the light guide plate (44).
3. Display device according to claim 1 or 2, characterized in that the light guide plate (44) has light-reflecting side surfaces (50) adjacent to the first diffuser layer (22) for reflecting light radiated into the light guide plate (44) by the further light sources (46).
4. Display device according to claim 2 or 3, characterized in that at least one light guide projection (64) projects from the light entry side (62) of the light guide plate (44) with a light entry side (66) facing away from the light guide plate (44), which light entry side (66) is connected to one or more visible light emitting light sources (28) of the backlight unit (24).
5. Display device according to claim 3 or 4, characterized in that the recess (40) is arranged within the first diffuser layer (22) and at a distance from its circumferential outer edge (42).
6. A display device with an IR camera for a vehicle, comprising an electro-optical display (12) having a front side (14) with a display surface (16) and a rear side (18), a backlighting unit (24) facing the rear side (18) of the display (12) for emitting visible backlighting light for backlighting the display (12), wherein the backlighting unit (24) has reflectors (30) and backlighting light sources (28) for directly emitting the backlighting light in the direction of the rear side (18) of the display (12), one or more IR light sources (34) for emitting IR light into an area (36) in front of the display surface (16) of the display (12), a first diffuser layer (22') arranged between the backlighting unit (24) and the display (12) and having a circumferential outer edge (42) has,wherein the first diffuser layer (22') has on its top and / or bottom side light-refracting and / or light-deflecting light distribution homogenization properties in the form of prints and / or surface structures and / or has within the first diffuser layer (22') light-refracting and / or light-deflecting light distribution homogenization properties, wherein these light distribution homogenization properties gradually decrease within an outer edge region (45) extending to the outer edge (42) of the first diffuser layer (22') and in the outer edge region (45) a partial region (44') with a, exposed outer edge section (43') is free or almost free of these light distribution homogenization properties, wherein the backlighting unit (24) has further light sources (46) for emitting visible light into the exposed outer edge section (43') of the partial region (44') of the outer edge region (45), which is provided for backlighting the display (12) with light emerging from the upper side of the diffuser layer (22') located in the partial region (44') of the outer edge region, and an IR camera (32) which is arranged within the backlighting unit (24) in alignment with the partial region of the outer edge region.
7. A display device with an IR camera for a vehicle, comprising an electro-optical display (12) having a front side (14) with a display surface (16) and a rear side (18), a backlighting unit (24) facing the rear side (18) of the display (12) for emitting visible backlighting light for backlighting the display (12), wherein the backlighting unit (24) has reflectors (30) and backlighting light sources (28) for directly emitting the backlighting light toward the rear side (18) of the display (12), one or more IR light sources (34) for emitting IR light into an area (36) in front of the display surface (16) of the display (12), a first diffuser layer (22') arranged between the backlighting unit (24) and the display (12),wherein the first diffuser layer (22') has on its top and / or bottom side light-refracting and / or light-deflecting light distribution homogenization properties in the form of prints and / or surface structures and / or has within the first diffuser layer (22') light-refracting and / or light-deflecting light distribution homogenization properties, wherein these light distribution homogenization properties are within an inner region (45) of the first diffuser layer (22'), gradually decrease and is free or almost free of these light distribution homogenization properties in a partial area (44') lying within this area (45), wherein light sources (28) of the backlighting unit (24) are arranged in alignment with the partial area (44'), and an IR camera (32) which is arranged within the backlighting unit (24) in alignment with the partial area of the outer edge area.
8. Display device according to claim 7, characterized in that at least one light guide projection (64) with a light entry side (66) facing away from the partial area, which light entry side is opposite one or more light sources (28) of the backlighting unit (24) emitting visible light, projects from the light entry side (62) of the partial area which is free or almost free of light distribution homogenization properties.
9. Display device according to claim 7 or 8, characterized in that the partial area free or almost free of light distribution homogenization properties is arranged within the first diffuser layer (22) and at a distance from its circumferential outer edge (42).
10. A display device with an IR camera for a vehicle, comprising an electro-optical display (12) having a front side (14) with a display surface (16) and a rear side (18), a backlighting unit (24) facing the rear side (18) of the display (12) for emitting visible backlighting light for backlighting the display (12), wherein the backlighting unit (24) has reflectors (30) and backlighting light sources (28) for directly emitting the backlighting light toward the rear side (18) of the display (12), one or more IR light sources (34) for emitting IR light into an area (36) in front of the display surface (16) of the display (12), a first diffuser layer (22) arranged between the backlighting unit (24) and the display (12), wherein the first diffuser layer (22) has a recess (40) in which a carrier element (67) with OLEDs and / or micro-LEDs for emitting visible backlighting light in the direction of the rear side of the display (12) is arranged, and an IR camera (32) arranged within the backlighting unit (24) in alignment with the carrier element (67).
11. Display device according to one of claims 1 to 10, characterized in that the backlighting unit (24) has a plurality of reflectors (30) held by a carrier element (26), each of which is assigned at least one light source (28) for visible light, which is arranged within the reflector (30).
12. Display device according to one of claims 1 to 11, characterized by a further diffuser layer (56) which is arranged above the first diffuser layer (22) and has a recess aligned with the recess (40) or the partial area of the first diffuser layer (22) which is free or almost free of light distribution homogenization properties, with an edge area which covers the interface between the light guide plate (44) or partial area and the first diffuser layer (22).
13. Display device with IR camera for a vehicle, with an electro-optical display (12) having a front side (14) with a display surface (16) and a rear side (18), a backlighting unit (24) facing the rear side (18) of the display (12) for emitting visible backlighting light for backlighting the display (12), wherein the backlighting unit (24) has reflectors (30) and backlighting light sources (28) for directly emitting the backlighting light in the direction of the rear side (18) of the display (12), one or more IR light sources (34) for emitting IR light into an area in front of the display surface (16) of the display (12), a first diffuser layer (22) arranged between the backlighting unit (24) and the display (12), and an IR camera (32) arranged in one of the reflectors (30) of the backlighting unit (24).
14. Display device according to one of claims 1 to 13, characterized in that in addition to the first diffuser layer (22) and, if present, to the further diffuser layer (56) between the display (12) and the backlight unit (24), an optical brightness enhancement layer and / or a transreflective polarization layer is arranged, wherein each further optical layer has a recess and wherein all recesses are aligned with the recess (40) or the partial area in the first diffuser layer (22) which is free or almost free of light distribution homogenization properties.
15. Display device according to one of claims 1 to 14, characterized by a first mirror reflection polarization film arranged on the rear side (18) of the display (12) or opposite thereto for reflecting visible backlighting light whose polarization deviates from the polarization direction of a rear polarization filter of the display (12), wherein backlighting light reflected by the first mirror reflection polarization film can be reflected by the reflectors (30) of the backlighting unit (24) back in the direction of the first mirror reflection polarization film with a change in its polarization direction.
16. Display device according to claim 15, characterized in that the first mirror reflection polarization film also reflects IR light whose polarization deviates from the polarization direction of the rear polarization filter of the display (12), and that an IR reflection film is arranged below the IR light sources (34) for changing the Polarization direction reflection of IR light reflected by the first mirror reflection polarization film.
17. Display device according to one of claims 1 to 16, characterized by a second mirror reflection polarization film arranged below the backlight unit for reflecting IR light whose polarization deviates from the polarization direction of a rear polarization filter of the display (12), and an IR reflection film arranged below the IR light sources (34) for reflecting IR light reflected by the second mirror reflection polarization film while changing the polarization direction.
18. Display device according to one of claims 1 to 17, characterized in that the IR light sources (34) emit NIR light and that the IR camera (32) is an NIR camera in the form of a line scan camera or as a 2D camera.
19. Display device according to one of claims 1 to 18, characterized by a touch panel for manual input of commands by touching the display surface of the display (12).
20. Display device according to one of claims 1 to 19, characterized by an optical lens in front of the IR camera (32).
21. Display device according to one of claims 1 to 20, characterized by a further diffuser layer transparent to IR radiation in the region between the first diffuser layer (22) and the rear side (18) of the display (12).
22. Display device according to one of claims 1 to 21, characterized in that the at least one IR light source (34) is arranged in an area offset laterally to the display (12), such as within a frame (54) surrounding the display (12), or below or is positioned in the first diffuser layer (22) or below or in the backlight unit (24)