Privacy display for installation in a dashboard of a vehicle, with real and virtual image generation in alternation

Abstract

The invention relates to a privacy display for installation in a dashboard of a vehicle, comprising: - an image generator for outputting a light beam having desired display content, the image generator having a polarization switching element for switching the light beam between a first and a second polarization; - a cover pane for letting the light beam through and for placement in a surface portion of the dashboard that faces an occupant in a front vehicle seat; and - in the beam path between the image generator and the cover pane, a first mirror which reflects the light beam when the light beam has the first polarization and which transmits the light beam when the light beam has the second polarization, a second mirror which reflects the transmitted light beam, and a third mirror which reflects to the cover pane the light beam reflected by the first / second mirror, so that said light beam subsequently reaches the occupant eye-box directly; - wherein at least one of these mirrors is an imaging or magnifying concave mirror so that, in the case of the second polarization, the display content is imaged to form a real image floating between the eye-box and the cover pane and, in the case of the first polarization, the display content appears to the occupant as a virtual image.

Description

[0001] Description

[0002] Privacy display for installation in a vehicle instrument panel, with alternating real and virtual image generation

[0003] The invention relates to a privacy display designed for installation in a vehicle instrument panel and for generating a real image suspended in the air for a vehicle occupant. The invention also relates to a corresponding operating method, a correspondingly configured control unit, and a vehicle equipped therewith.

[0004] Head-up displays (HUDs) are particularly well known for motor vehicles. These are designed to project a virtual image into the field of vision of an occupant via reflection from a partially transparent reflective screen, typically a windshield or a specially designed combiner screen. This allows, for example, speed information and other useful navigation, warning, and vehicle operating information to be superimposed on the real environment in front of the vehicle observed by the driver or another occupant. For this purpose, a conventional HUD for the driver, for example, comprises a projection unit housed in the instrument panel. This generates a beam of light with the desired display content and projects it in a suitable shape and direction onto the windshield or the combiner screen, from which it is reflected to the driver's eyes or to a spatial area defined for this purpose (eyebox).To read a head-up display, the driver does not need to take their eyes off the road and, with a suitable design of the projection optics, does not need to significantly refocus. Head-up displays are also proposed in the prior art for use as passenger entertainment or as driver entertainment during parking or autonomous driving. In addition to virtual image display, the generation of a real image suspended in the air for one or more viewers using an imaging concave mirror is known, for example, from CN 217821128 U. The beam path leads to the eyeboxes of a driver and / or passenger via reflection on the windshield.

[0005] However, it's not easy to display the HUD image in the transparent area of ​​the windshield with sufficient brightness and high contrast, even in high ambient light. Furthermore, compared to a virtual projection, a real image only allows for relatively small image sizes or inch dimensions for diagonal lengths, which in turn limits its applicability.

[0006] It is an object of the present invention to provide an alternative and / or improved display concept for a passenger of a vehicle, which is particularly well suited as passenger entertainment and enables an improvement over known devices, for example with regard to possible applications, installation space, contrast, visibility, image quality and / or other aspects.

[0007] This object is achieved by a privacy display according to claim 1, as well as by an associated operating method, a correspondingly configured control unit, and a vehicle equipped therewith according to the independent claims. Further embodiments are specified in the dependent claims. All further features and effects mentioned in the claims and the following description for the privacy display also apply to the method, the control unit, and the vehicle, and vice versa.

[0008] According to a first aspect, a privacy display is provided that is designed for installation in an instrument panel of a vehicle. The vehicle can be a motor vehicle, but also any other land, air, or water vehicle. Unless otherwise stated, all spatial orientation terms used herein, such as "top," "bottom," "lateral," "horizontal," "vertical," etc., refer to the usual vehicle-fixed Cartesian coordinate system with mutually perpendicular longitudinal, transverse, and vertical directions of the vehicle.

[0009] The privacy display comprises an imager configured to generate a desired display content and a light beam (herein also referred to as "projector light") that conveys this content. The imager comprises a polarization switching element configured to switch the polarization (i.e., the polarization state) of the light beam between a predetermined first and a predetermined second polarization. Suitable electronically controllable switching elements, for example, based on liquid crystals, are known to those skilled in the art.

[0010] In principle, any imaging technology is suitable for the imager. In particular, it can be designed to dynamically generate the required or desired display content in a two-dimensional pixel matrix. In particular, the imager can be designed as a light-transmitting or light-emitting flat screen, such as a liquid crystal display (LCD) or a pLED or OLED display, but alternatively also as a projector-based imager or a waveguide-based display. This makes it possible, for example, to generate display content that reproduces a work computer desktop or an open book and / or whose content can be controlled by the relevant occupant via a suitable user interface in the vehicle (such as via acoustic input, touchpad, keyboard, and much more).On the other hand, this can be used to create display content that reproduces a video film or a video game, etc. The privacy display also comprises a cover plate (also called cover glass) designed to allow the light beam to pass through. The cover plate (or its user-facing surface) is designed, when the privacy display is installed in the vehicle, to form a surface section of the instrument panel that faces a vehicle occupant in a front vehicle seat, i.e., its surface is arranged directly opposite the occupant. The cover plate and in particular its user-facing surface can, for example, be planar (i.e., flat). However, the cover plate can also have a free-form surface on one or both sides to produce a predetermined optical effect.

[0011] The privacy display further comprises projection and imaging optics arranged in the beam path between the imager and the cover plate. These are designed such that the light beam exits the cover plate directly toward an eyebox predetermined for the eyes of the occupant, the display content of the light beam with the second polarization is projected onto a real image suspended in the air between the eyebox and the cover plate, and the display content of the light beam with the first polarization is presented to the occupant as a virtual image suspended beyond the third mirror at a predetermined size and distance. For this purpose, the projection and imaging optics comprise three mirrors, one, two, or all three of which are designed as imaging or magnifying concave mirrors.

[0012] A first of these mirrors faces the imager with its mirror surface and is designed for essentially loss-free reflection of the light beam with the first polarization and for essentially loss-free transmission of the light beam with the second polarization. A second mirror is arranged in the beam path of the transmitted light beam and is designed for essentially loss-free reflection of the transmitted light beam with the second polarization. Both the first and the second mirror are designed to reflect the light beam to a third mirror. The third mirror is therefore arranged with its mirror surface opposite the mirror surfaces of the first and second mirrors and is designed to reflect the light beam with the first and second polarizations towards the cover plate.For example, "essentially lossless reflection" can mean a reflection coefficient of more than 50%, in particular more than 60 or 70%, and ideally more than 80 or 90%. Similarly, "essentially lossless transmission" can mean a transmission coefficient of more than 50%, in particular more than 60 or 70%, and ideally more than 80 or 90%.

[0013] From the third mirror onwards, the beam path for the light beam with the first and second polarizations is the same: It passes through the cover plate and exits it in a direction of radiation that leads directly (i.e., without further deflection surfaces) to a spatial area predetermined for the eyes of the occupant (eyebox). The imaging and / or magnifying concave mirror(s) with their respective focal lengths are designed such that the display content of the light beam with the second polarization is projected onto a real image that floats freely in the air in the passenger compartment at a predetermined position between the eyebox and the cover plate, and the display content of the light beam with the first polarization appears to the occupant as a virtual image floating beyond the third mirror at a predetermined size and distance.

[0014] The privacy display is thus designed to control the polarization switching element to generate the corresponding polarization state of the light beam, depending on whether a real or virtual image with these properties is required. The occupant can see the respective image when their eyes are in the aforementioned eyebox and they are looking toward the cover panel. Unlike the virtual image, the real image can be captured by light-sensitive material (e.g., photographic film) and made visible to everyone by means of a diffusely light-scattering surface (e.g., a sheet of paper) when such a material or surface is placed in its image position.

[0015] As is customary, an eyebox is defined as a two- or three-dimensional spatial area from which the displayed real or virtual image is fully visible. In other words, the light beam is essentially confined to this spatial area. Therefore, the generated image is only visible to those occupants whose eyes are located within the designated eyebox, which, for example, does not extend beyond the width of their vehicle seat. This allows confidential content to be displayed to these occupants (“privacy”). On the other hand, other occupants, such as the driver, are not visually disturbed by this display because they cannot see it.

[0016] One idea of ​​the present invention consists of a projector (privacy display) that can be switched between a real image and a virtual projection for different applications, as well as the integration and the proposed arrangement of this projector in the instrument panel. The integration of a projector in a vehicle is difficult both in terms of installation space and in terms of freedom from reflections and visibility in high ambient brightness. These difficulties can be overcome by the design and arrangement of the privacy display in the instrument panel proposed here. Compared to a head-up display, in which the image of a bright exterior environment of the vehicle is superimposed, it has the advantage that its cover screen, with the interior of the instrument panel behind it, serves as the image background.This allows the image brightness to be increased largely independently of the ambient brightness and also the contrast to be significantly improved.

[0017] In particular, a partially shared beam path enables a spatially compact combination of two projection options in one projector: a real image with a relatively small diagonal or image size at a shorter distance from the occupant, and a virtual projection with a significantly larger diagonal or image size at a greater distance from the occupant. The use of a shared image generator further reduces the required installation space.

[0018] Using the aforementioned projection and imaging optics, and in particular by appropriately selecting their effective focal length, the real image can be generated at a significantly shorter distance from the occupant's eyes than with virtual image generation. For the privacy display in question, this distance can be less than one meter or even less than half a meter, for example. Such distances can be particularly suited to reading or working. The significantly greater distance of the virtual image, which can be between one and ten meters or even more from the occupant's eyes and therefore does not require as much eye focus as when reading, can be designed for entertainment content such as films or videos, or for driving-related information for the driver.For example, it may be of interest to the passenger, for autonomous driving or when stationary, if the driver or passenger can optionally use the same privacy display that enables this virtual display to work or read messages or other digitally displayable content at a significantly shorter image distance and with a higher spatial resolution than can be achieved with the real image.

[0019] In addition to its imaging effect, the respective concave mirror can also be designed, for example, to have a beam-deflecting, image-magnifying and / or image-correcting effect on the light beam. Alternatively or additionally, the projection and imaging optics can also comprise other imaging elements, such as lenses, for generating the real or virtual image, as well as other deflecting elements, such as plane mirrors, for folding the beam path. According to one embodiment, the first polarization is a linear polarization with a predetermined polarization direction, and the second polarization is a linear polarization with a polarization direction perpendicular (i.e., orthogonal) thereto. Purely by way of example, in this embodiment, the first polarization can correspond to a vertical or p-polarization and the second polarization to a horizontal or s-polarization, or vice versa.The p- and s-polarization directions can be defined, for example, with reference to one of the reflection or transmission surfaces of the privacy display, such as one of the three mirrors.

[0020] According to one embodiment, at least the second mirror is designed as an imaging concave mirror, which contributes to imaging the display content generated in the image generator onto the real image suspended between the eyebox and the cover plate. If the third mirror is also designed as an imaging concave mirror, this allows for particularly high imaging quality and / or other specific requirements such as a predetermined image distance, etc., to be met. In particular, the first mirror can be a plane mirror or a concave mirror.

[0021] According to one embodiment, at least the third mirror is designed as a magnifying or imaging concave mirror, which, in the case of the first polarization, contributes to the representation of the display content generated in the imager as the virtual image floating beyond the third mirror with a predetermined size and distance from the eyebox, and, in the case of the second polarization, contributes to the imaging of the display content generated in the imager onto the real image floating between the eyebox and the cover plate. In particular, the first mirror can be a plane mirror or a concave mirror.

[0022] According to one embodiment, the user-facing surface of the cover panel is inclined at a predetermined first angle of inclination from the vertical to a vehicle floor, i.e., it is arranged obliquely with respect to the height direction of the vehicle such that an upper edge of this surface is closer to the occupant and their vehicle seat in the vehicle longitudinal direction than its lower edge. This ensures that light rays coming from the sun or artificial light sources inside and outside the vehicle and striking the cover panel from above are always reflected by the cover panel in the direction of the vehicle floor and therefore cannot enter the eyes of the driver or other occupants as disturbing reflections. In addition, such an orientation of the cover panel away from the occupant and towards the floor can make it more difficult for the occupant in question to gain an unwanted view into the interior of the privacy display. The first angle of inclination, which is relative to the vertical (i.e.,the vehicle height direction) can be, for example, at least about 10°, in particular at least about 20° or even at least about 30°.

[0023] According to one embodiment, the projection and imaging optics are designed to display the real image in a real image plane or curved image surface floating in the air between the cover screen and the eyebox. By appropriately selecting the mutual arrangement and design of the image generator and the second and third mirrors, an optimal orientation (in terms of image inclination) of the floating image plane or image surface for viewing the floating real image can be achieved. This orientation is largely independent of the surface geometry of the instrument panel or the cover screen and can therefore deviate significantly from it. In particular, this allows a floating real image plane or image surface to be generated at positions and with orientations that are not available for hard display surfaces due to the arm and legroom required for the occupant in the vehicle.

[0024] In particular, this floating real image plane / image surface can be inclined at a predetermined second angle of inclination from the vertical towards a roof liner (in other words upwards, and thus towards the eyebox). As a result of this inclination, the floating real image plane / image surface is inclined towards the user, which can be particularly ergonomic. Particularly when reading, this can significantly reduce the variation in image distance along the floating real image plane / image surface and the associated variation in the focus of the reader's eyes. The second angle of inclination, which is measured with respect to the vertical (i.e. the vehicle height direction) and is independent of the first angle of inclination, can be, for example, at least approximately 10°, in particular at least approximately 20° or even at least approximately 30°.

[0025] The cover plate can optionally also contribute to the shaping and / or directing of the light beam, for example, through a specific prism shape, and thus form part of the projection and imaging optics. According to one embodiment, the cover plate can be prism-shaped to deflect the light beam upwards, in order to vertically compress the installation space required for the privacy display and thereby output the light beam directly toward the eyebox. In particular, the prism-shaped cover plate can have an at least approximately triangular shape in a vertical longitudinal section, tapering downwards. This allows for even greater freedom in the design of the imaging and projection optics.For example, the cover plate can be designed as a prism, in particular a free-form prism, which follows the predetermined shape of the instrument panel and at the same time provides additional deflection of the light beam.

[0026] In particular, the cover screen can additionally have particle addition, coloring or tinting and / or a polarization filter and can thus be darkened to such an extent that it creates a dark or even black image background for a particularly high-contrast representation of the real or virtual image. Since in this case the cover screen, with the interior of the instrument panel and the privacy display behind it, serves as the image background, the image contrast can be increased by darkening it. And since, unlike the head-up display mentioned above, the image is not projected against the bright exterior of the vehicle, perfect visibility can be achieved with a significantly lower intensity of the projector light than with a HUD, so that even despite a certain attenuation of the projector light due to the darkened cover screen, a higher image contrast can be achieved.

[0027] In other words, by deliberately darkening the cover, it can serve as a contrast medium for displaying the real or virtual image with the desired contrast. At the same time, the cover can also largely block the view of the vehicle occupants into the interior of the privacy display. Since ambient light, unlike projector light, has to pass through the cover twice to illuminate the interior of the privacy display for the occupants, it can be attenuated at least twice as much as the projector light by light-absorbing particles or a suitable polarization filter in the cover.

[0028] According to a further aspect, a method for operating a privacy display presented herein is provided. The method comprises generating or receiving a predetermined trigger signal for generating the real image or another predetermined trigger signal for generating the virtual image, and thereby triggering the polarization switching element to switch the polarization state of the light beam either to the aforementioned second or to the aforementioned first polarization. A suitable trigger signal can be generated, for example, by the user themselves via any user interface designed for this purpose and / or automatically by detecting a predetermined condition, such as a transition to a manually controlled driving regime, etc.

[0029] According to a further aspect, a control unit is provided that is designed and configured to automatically execute this method and can, in particular (but not necessarily), be an integral component of the privacy display. For this purpose, a corresponding computer program (software) can be loaded into a processor of the control unit, for example, and run during operation of the privacy display.

[0030] According to a further aspect, the above vehicle is provided. The vehicle comprises a windshield, an instrument panel extending thereunder, and at least one front vehicle seat arranged opposite the instrument panel. It is equipped with at least one privacy display of the type presented herein and with the above control unit. Each of these privacy displays is integrated into the instrument panel such that its cover forms a surface portion of the instrument panel facing a vehicle occupant in one of the front vehicle seats.

[0031] According to one embodiment, the cover plate is arranged in the instrument panel such that its user-facing surface (i.e., the aforementioned surface section) is flush with adjacent surface sections of the instrument panel. In other words, in this embodiment, the user-facing surface of the cover plate follows the surface shape of the instrument panel or forms a continuous continuation of it. Compared to the formation of a recess in the surface of the instrument panel, this can both increase user comfort and contribute to saving installation space.

[0032] In particular, one of the privacy displays can be arranged opposite a passenger seat and designed for use as passenger entertainment. Alternatively or additionally, one of the privacy displays can be arranged opposite a driver's seat and designed, for example, for use as driver entertainment during autonomous driving or in a parked vehicle.

[0033] The above aspects of the invention and their embodiments and specific configurations are explained in more detail below using an example shown in the accompanying drawing. The drawing is to be understood as a purely schematic illustration of the basic optical design principle and is not to scale. It shows:

[0034] Figure 1 shows a vertical longitudinal section of a section of a vehicle with a privacy display according to an embodiment of the invention.

[0035] All of the various embodiments, alternatives, and specific design features of the privacy display, its operating method, the associated control unit, and the vehicle according to the above aspects of the invention mentioned above in the description and in the subsequent claims can be implemented in the example shown in Fig. 1, in particular also alternatively or in addition to the features shown therein. Therefore, they will not all be repeated below. The same applies accordingly to the definitions and effects already given above with regard to individual features shown in Fig. 1.

[0036] Fig. 1 shows, in a highly simplified schematic vertical longitudinal sectional view, an embodiment of a vehicle 1 with a privacy display 2 of the type presented herein. In this example, the vehicle 1 is a motor vehicle, which is only indicated in Fig. 1 by its windshield 3 and an instrument panel 4 extending underneath. As already mentioned, the spatial orientation terms such as "above", "below", "side", "horizontal", "vertical", etc. refer to the usual vehicle-fixed Cartesian coordinate system K with mutually perpendicular longitudinal, transverse and vertical directions X, Y and Z of the vehicle 1.

[0037] The privacy display 2 is integrated inside the instrument panel 4 and contains an image generator 5, which is designed to generate a light beam L1 or L2 with the desired display content, and a cover plate 6 designed to transmit the light beam L1 / L2. The image generator 5 is only schematically indicated in Fig. 1 by a functional block. It can be designed purely as an example as a flat screen, in particular a liquid crystal display (LCD), so that the desired display content is dynamically generated in its display area (not shown separately). However, the image generator 5 can also be designed as a projector and, for example, contain a light-diffusing projection surface (not shown separately), onto which the respective display content is projected as a real image.Alternatively, the projector-based imager 5 can comprise a laser scanner or a light source with suitable illumination optics for generating a homogeneous, collimated illumination beam and an image generation surface illuminated thereby (for example in the form of an LCOS, Liquid Crystal on Silicon, or DMD, Digital Micromirror Device, not shown separately), which can be controlled pixel by pixel to generate the display content.

[0038] The imager 5 comprises a polarization switching element 10, which is designed to switch the polarization (i.e., the polarization state) of the light beam between a predetermined first (L1) and a predetermined second (L2) polarization. Purely by way of example, in Fig. 1, the first polarization is a vertical or p-polarization, and the second polarization is a horizontal or s-polarization.

[0039] The user-side surface of the cover panel 6 forms a surface section 4a of the instrument panel 4, which faces a vehicle occupant on a front vehicle seat (not shown), so that its surface is arranged directly opposite the occupant. The occupant, in this example a front passenger, is only indicated by a spatial area E (eyebox) predetermined for his or her eyes. The eyebox E, in turn, is sketched purely symbolically and is located in the area of ​​the corresponding front vehicle seat or its headrest. The light beam L1 / L2 (also called projector light) is only schematically indicated by its central beam, which leads from a center of the image generation surface of the projector 5 (e.g., display surface, projector surface, etc.) to a center of the eyebox E.

[0040] Furthermore, the privacy display 2 comprises projection and imaging optics arranged in the beam path of the projector light L1 / L2 between the imager 5 and the cover plate 6. The projection and imaging optics comprise three mirrors 7, 8, and 9, which in this example are all designed as imaging or magnifying concave mirrors. The first mirror 8 faces the imager 5 with its mirror surface and is designed for essentially loss-free reflection of the light beam L1 with the first polarization and for essentially loss-free transmission of the light beam L2 with the second polarization. The second mirror 9 is arranged in the beam path of the transmitted light beam L2 and is designed for essentially loss-free reflection of this transmitted light beam L2 with the second polarization.Both the first and the second mirror 8 / 9 are designed to reflect the light beam L1 / L2 to the third mirror 7, from which it is reflected to the cover plate 6.

[0041] The projection and imaging optics are designed such that the light beam L1 / L2 leaves the cover plate 6 directly in the direction of the eyebox E, the display content of the light beam L2 with the second polarization is projected onto a real image B floating in the air between the eyebox E and the cover plate 6, and the display content of the light beam L1 with the first polarization is presented to the occupant as a virtual image V floating beyond the third mirror 7 at a predetermined comfortable size and distance.

[0042] By appropriately selecting the mutual arrangement and design of the image generator 5 and the projection and imaging optics, an optimal position (in terms of image distance) and orientation (in terms of image inclination) of the floating real image B between the cover screen 6 and the eyebox E can be achieved, which would not be possible with conventional display technologies such as flat screens or head-up displays. In particular, the occupant can view the floating real image B at a comfortable reading distance of, for example, approximately 30-50 cm from their eyes, without restricting their arm and legroom and without the image inclination depending on the geometry of the surface section 4a of the instrument panel 4.

[0043] In this case, the cover plate 6 (in Fig. 1 purely exemplary planar, designed as a plane-parallel plate) or its user-side surface is provided with the above-mentioned first angle of inclination <p aus der Vertikalen heraus zu einem Fahrzeugboden (nicht extra dargestellt) geneigt. Mit anderen Worten ist der dadurch gebildete Oberflächenabschnitt 4a derart schräg bezüglich der Höhenrichtung Z des Fahrzeugs 1 angeordnet, dass sein oberer Rand in Fahrzeuglängsrichtung X näher an dem Insassen bzw. seiner Eyebox E als sein unterer Rand ist. Dadurch lässt sich erreichen, dass jede Art von Umgebungslichtstrahlen, die von der Sonne oder künstlichen Beleuchtungsquellen kommen können, von der Deckscheibe 6 stets zum Fahrzeugboden gespiegelt werden und daher nicht als Störreflexe in die Augen des Fahrers oder des genannten Insassen gelangen können.In addition, this angled orientation of the opening aperture away from the occupant and towards the ground makes it difficult for the occupant to gain an unwanted view into the interior of the Privacy Display 2. The first angle of inclination <p kann beispielsweise mindestens etwa 10°, insbesondere mindestens etwa 20° oder sogar mindestens etwa 30° betragen. Diese Schrägstellung der Deckscheibe 6 bedeutet in diesem Beispiel eine Verkippung / Drehung der Deckscheibe 6 aus einer vertikal ausgerichteten Lage um eine imaginäre Horizontalachse, die der Fahrzeugquerrichtung Y entspricht.

[0044] In this example, the real image B is generated in a floating real image plane or surface, which is tilted (i.e., rotated) in an opposite rotation direction from a vertically oriented position by a second angle of inclination, which may, for example, be at least approximately 10°, in particular at least approximately 20°, or even at least approximately 30°, about a rotation axis extending in the vehicle transverse direction Y. The second angle of inclination is selected independently of the first angle of inclination and may, for example, correspond to a particularly ergonomic spatial orientation of the real image B.

[0045] The privacy display 2 is designed, via appropriate control of the polarization switching element 10, to generate the light beam L1 / L2 with either the first (L1) or the second (L2) polarization, depending on whether real or virtual image generation with the above properties is currently required. For this purpose, a suitably configured control unit (not shown) can be installed or integrated in the privacy display 2 or elsewhere in the vehicle 1. The beam path (in the sense of the propagation direction) of the light beam L1 / L2 is the same for both polarizations, beginning with its reflection at the third mirror 7.

[0046] The occupant can see the respective image BA / if their eyes are in the designated eyebox E and they are looking toward the cover plate 6. It is not visible to other occupants whose eyes are not in said eyebox E (privacy). Unlike the virtual image V, the real image B can be recorded using light-sensitive material (e.g., photographic film) and made visible to everyone using a diffusely light-scattering surface (e.g., a sheet of paper) if such a material or surface is brought into its image position shown in Fig. 1.

[0047] List of reference symbols

[0048] 1 vehicle

[0049] 2 Privacy Display

[0050] 3 Windscreen

[0051] 4 Instrument panel

[0052] 4a Surface section of the instrument panel facing a vehicle occupant in a front vehicle seat

[0053] 5 imagers

[0054] 6 Cover plate

[0055] 7 third mirror

[0056] 8 first mirror

[0057] 9 second mirror

[0058] L1 light beam with the first polarization

[0059] L2 light beam with the second polarization

[0060] B real image floating in the air

[0061] V virtual image

[0062] E Eyebox P first tilt angle

[0063] K vehicle-fixed coordinate system

[0064] X, Y, Z longitudinal, transverse and height directions of the vehicle

Claims

Claims 1. A privacy display (2) for installation in an instrument panel (4) of a vehicle (1), comprising: an image generator (5) designed to output a light beam (L1, L2) with the desired display content and comprising a polarization switching element (10) for switching the light beam (L1, L2) between a predetermined first and a predetermined second polarization; a cover plate (6) designed to transmit the light beam (L1, L2) and for arrangement in a surface section (4a) of the instrument panel (4) facing a vehicle occupant in a front vehicle seat;and in the beam path between the imager (5) and the cover plate (6), a first mirror (8) which is designed for a substantially loss-free reflection of the light beam (L1) with the first polarization and for a substantially loss-free transmission of the light beam (L2) with the second polarization, a second mirror (9) arranged behind it, which is designed for a substantially loss-free reflection of the transmitted light beam (L2) with the second polarization, and a third mirror (7) which is designed to reflect the light beam (L1, L2) reflected by the first and second mirrors (8, 9) towards the cover plate (6), so that it directly illuminates the cover plate (7); Direction of an eyebox (E) predetermined for the eyes of the occupant; wherein at least one of these three mirrors (7, 8, 9) is an imaging or magnifying concave mirror, so that the display content of the light beam (L2) with the second polarization is imaged onto a real image (B) floating in the air between the eyebox (E) and the cover plate (6), and the display content of the light beam (L1) with the first polarization is shown to the occupant as a virtual image (V) floating beyond the third mirror (7).

2. Privacy display (2) according to claim 1, wherein the first polarization is a linear polarization with a predetermined polarization direction; and the second polarization is a linear polarization with a polarization direction perpendicular thereto.

3. Privacy display (2) according to claim 1 or 2, wherein at least the second mirror (9) is designed as an imaging concave mirror which contributes to imaging the display content generated in the image generator (5) onto the real image (B) floating between the eyebox (E) and the cover plate (6).

4. Privacy display (2) according to one of the preceding claims, wherein at least the third mirror (7) is designed as a magnifying or imaging concave mirror, which in the case of the first polarization for displaying the display content generated in the image generator (5) as the virtual image (V) floating beyond the third mirror (7) with a predetermined size and distance from the eyebox (E) and in the case of the second polarization for displaying the display content generated in the image generator (5) generated display content to the real image (B) floating between the eyebox (E) and the cover plate (6).

5. Privacy display (2) according to one of the preceding claims, wherein the cover plate (6) is prism-shaped for deflecting the respective light beam (L1, L2) upwards in order to vertically compress an installation space required for the privacy display (2) and thereby output the light beam (L1, L2) directly in the direction of the eyebox (E); and the prism-shaped cover plate (6) in a vertical longitudinal section preferably has a downwardly tapering, in particular at least approximately triangular, shape.

6. Privacy display (2) according to one of the preceding claims, wherein a user-side surface of the cover plate (6) forming said surface portion (4a) of the instrument panel (4) is inclined at a predetermined first angle of inclination (cp) from the vertical to a vehicle floor.

7. A method for operating a privacy display (2) according to one of the preceding claims, comprising the steps: Generating or receiving a predetermined trigger signal for generating the real image (B) or the virtual image (V); and thereby triggering the polarization switching element (10) to switch the light beam (L1, L2) either to the second or to the first polarization.

8. Control unit which is designed and arranged to automatically carry out the method according to claim 7.

9. A vehicle (1) with mutually perpendicular longitudinal, transverse, and vertical directions (X, Y, Z) of a vehicle-fixed Cartesian coordinate system (K), in particular a motor vehicle, comprising: a windshield (3), an instrument panel (4) extending thereunder, and at least one front vehicle seat arranged opposite the instrument panel (4); at least one privacy display (2) according to one of claims 1 to 6, which is integrated into the instrument panel (4) such that its cover panel (6) forms a surface section (4a) of the instrument panel (4) facing a vehicle occupant on one of the front vehicle seats; and at least one associated control unit according to claim 8; wherein the respective cover panel (6) is preferably arranged in the instrument panel (4) such that its user-facing surface is flush with adjacent surface sections of the instrument panel (4).

10. The vehicle (1) according to claim 9, wherein one of the privacy displays (2) is arranged opposite a passenger seat and is designed for use as passenger entertainment; and / or one of the privacy displays (2) is arranged opposite a driver's seat and is preferably designed for use as driver entertainment during autonomous driving or in a parked vehicle (1).

Images