FR3091931A1 - Motor vehicle display device - Google Patents

Abstract

The invention relates to a display device (1) for a vehicle. This device (1) comprising an autostereoscopic screen (10) suitable for rendering at least one 3D image (101) and a micro-mirror slide (12). The micromirror slide (12) is inclined at a determined angle relative to the autostereoscopic screen (10) so as to project the at least one 3D image (101) in an image plane (11) formed in front of the slide with micro-mirrors (12) with respect to a given point of view (100). Figure for the abstract: Figure 1

Description

Motor vehicle display device

The invention relates to Man-Machine interfaces with restitution of at least one three-dimensional (3D) image and more particularly to devices for displaying three-dimensional image(s) on board a vehicle, in particular of the automotive type. .

Technology background

Contemporary vehicles embed one or more display devices to display various and varied information to the driver of the vehicle to assist the driver in driving the vehicle. This or these display devices inform the driver, for example, of a number of parameters associated with the vehicle (for example the speed, the fuel consumption, the route to be followed). This information is displayed in two dimensions (2D) or in three dimensions (3D) for more recent vehicles.

There are several technologies for displaying 3D information through a three-dimensional image or a series of three-dimensional images. By way of example, document WO2015130996 discloses a visual display unit system creating a three-dimensional volumetric space inside a vehicle for displaying 3D images. We also know systems inspired by Pepper's ghost or optical systems based on holographic technology which are also capable of displaying 3D images.

However, the technologies that exist most often offer an illusion of a 3D effect more than a true real 3D image. The systems offering the display of a true real 3D image suffer from a significant bulk which limits their integration into the dashboard of a vehicle.

An object of the present invention is to provide a display device resolving one or more of the aforementioned drawbacks. The present invention proposes in particular a display device which makes it possible to display a real 3D image floating in the air facing an observer, for example facing the driver of a vehicle in which the display device object of the present invention.

According to a first aspect, the invention relates to a display device for a vehicle, this device comprising an autostereoscopic screen suitable for rendering at least one 3D image and a micro-mirror blade, the micro-mirror blade being inclined at a determined angle with respect to the autostereoscopic screen so as to project the at least one 3D image in an image plane formed in front of the micro-mirror plate with respect to a given point of view.

According to a variant, the at least one 3D image is masked from the given point of view, the at least one 3D image being rendered in an object plane located behind a plane comprising the micro-mirror blade with respect to the given point of view.

According to yet another variant, the image plane is orthogonal to the object plane.

According to another variant, the image plane is at a distance from the micro-mirror plate equivalent to a distance between the object plane and the micro-mirror plate.

According to yet another variant, the micro-mirror plate comprises two arrays of micro-mirrors arranged perpendicular to each other, each array of micro-mirrors comprising a series of micro-mirrors arranged parallel to each other others and arranged at regular intervals in the matrix.

According to an additional variant, the determined angle is equal to 45°.

According to another variant, the autostereoscopic screen is a lenticular array screen.

According to another variant, the autostereoscopic screen is a parallax barrier screen.

According to a second aspect, the invention relates to a dashboard for a vehicle incorporating the display device as described above according to the first aspect of the invention.

According to a third aspect, the invention relates to a vehicle, for example of the automobile type, comprising the display device as described above according to the first aspect of the invention or the dashboard according to the second aspect of the invention.

Brief description of figures

Other characteristics and advantages of the invention will emerge from the description of the non-limiting embodiments of the invention below, with reference to the appended figures 1 to 6, in which:

schematically illustrates a display device for a vehicle, according to a particular embodiment of the present invention;

illustrates a micro-mirror plate included in the display device of FIG. 1, according to a particular embodiment of the present invention;

illustrates the detail of a part of the micro-mirror blade of FIG. 2, according to a particular embodiment of the present invention;

illustrates the path of a ray of light in the micro-mirror plate of FIG. 2, according to a particular embodiment of the present invention;

illustrates a first example of an autostereoscopic screen included in the display device of FIG. 1, according to a particular embodiment of the present invention;

illustrates a second example of an autostereoscopic screen included in the display device of FIG. 1, according to a particular embodiment of the present invention.

A display device will now be described in the following with reference to FIGS. 1 to 6. The embodiments described below relate more particularly to an implementation of the display device according to the invention. within a vehicle, in particular a motor vehicle. However, any implementation in a different context, in particular in any type of vehicle (for example a train or an airplane), is also covered by the present invention.

According to a particular and non-limiting embodiment of the invention, a display device for a vehicle comprises an autostereoscopic screen (for example a lenticular autostereoscopic screen or an autostereoscopic screen with a parallax barrier) suitable for rendering and/or display of a 3D image or a sequence of 3D images. The display device also includes a micro-mirror blade. The micro-mirror blade is inclined at a determined angle relative to a plane comprising the autostereoscopic screen, for example 45°. The micro-mirror blade is configured in such a way as to project the 3D image rendered by the stereoscopic screen in an image plane formed in front of the blade, according to a given point of view, for example according to the point of view of the driver driving the vehicle comprising the display device.

The image obtained in the image plane is a real 3D image floating in the air in front of the micro-mirror blade according to the given point of view.

schematically illustrates a display device 1 for a vehicle, according to a particular and non-limiting embodiment of the present invention.

The device 1 is advantageously embedded in a vehicle, for example of the automobile type. The device 1 comprises an autostereoscopic screen 10 situated in an object plane. The autostereoscopic screen is a screen allowing to display several points of view of the same scene, for example 2, 8, 16, 64 points of view. Two examples of autostereoscopic screen will be described with regard to FIGS. 5 and 6. The content displayed by the autostereoscopic screen is represented by object A 101, object A 101 corresponding to the object to be projected in an image plane 11 by the display device 1. The image B 111 resulting from the projection of the object A 101 is formed on the image plane 11 via a micro-mirror blade 12 placed at a determined angle α, for example α=45°, with respect to the optical axis of the object plane 10. A detailed description of the micro-mirror blade 12 is provided with reference to FIGS. 2 to 4. The use of a micro-mirror blade mirrors such as that described with reference to FIGS. 2 to 4 makes it possible to obtain a real image 111 unlike a virtual image by using a conventional semi-transparent plate in systems based on the principle of Pepper's phantom for example. Furthermore, the use of the micro-mirror plate 12 makes it possible to render the real 3D image 111 in front of the micro-mirror plate 12 with respect to an observer 100. In other words, the image 111 is formed on a plane image 11 located between the observer 100 and the micro-mirror blade 12. Conversely, the object A 101 corresponding to the content (or to the image(s)) rendered by the autostereoscopic screen 10 is located behind the plane comprising the micro-mirror plate 12 relative to the point of view of the observer 100. In other words, the object A 101 is located beyond the plane comprising the micro-mirror plate 12 relative to the observer 100. A real image is an image formed when the rays of light are directed towards a fixed point, the real image being able to be projected or seen on a screen. A virtual image is the opposite of a real image, i.e. the rays of light that form this virtual image do not converge and a virtual image cannot be projected onto a screen.

The display device also comprises a box 13 which serves as a support for the micro-mirror plate 12 and makes it possible to hide the object A 101 as well as the autostereoscopic screen 10 from the view of the observer. According to a variant, the box 13 is formed by a recess in a dashboard of a vehicle which accommodates the display device 1. The image B 111 is formed at a distance d from the micro-mirror blade 12, the distance d corresponding to the norm of the segment [BC]. This distance d is equal or substantially equal to the distance between the autostereoscopic screen (or the object plane comprising this screen) and the micro-mirror plate 12, ie the norm of the segment [AC]. By 'substantially equal' is meant a slight difference between the distance d=BC and the distance AC, of the order of a few % (for example 1, 2, 5 or 10%), which can be observed and is due for example to minor imperfections of the blade 12 or of the positioning of the blade 12 relative to the screen 10. This distance d can vary by varying the positioning of the micro-mirror blade 12 relative to the autostereoscopic screen 10 (or the object plane including this screen). In the same way, the position of the image B 111 with respect to the micro-mirror plate 12 and to the display device 1 varies according to the angle α. According to variant embodiments, the angle α is equal for example to 50° or 55°, which makes it possible to shift the image 111 downwards from the field of vision of the observer 100; according to other examples, the angle α is equal for example to 35° or 40° which makes it possible to shift the image 111 towards the top of the field of vision of the observer 100.

According to variant embodiments, the micro-mirror plate 12 is replaced by a plate composed of a surface comprising diffractive optical elements or meta-surfaces configured for the projection of the object A 10 towards a real 3D image 111, as described above.

According to other variant embodiments, the autostereoscopic screen 10 is replaced by a display screen of the MLD type (from the English “Multi-Layer Display” or in French “Screen multilayers”) or by a holographic display device , for example of the SLM type (from the English “Spatial Light Modulator” or in French “spatial light modulator”).

illustrates the micro-mirror plate 12, according to a particular and non-limiting embodiment of the present invention.

The micro-mirror blade 12 corresponds for example to a multilayer structure, comprising for example 4 layers, namely 2 layers 22 and 23 each corresponding to a matrix of micro-mirrors and 2 other layers 21 and 24 enveloping the layers 22 and 23 The micro-mirror blade 12 corresponds for example to the ASKA 3D blade marketed by the company Asukanet. The micro-mirror blade 12 is configured to transmit the light received from the object B 101 (obtained or displayed by the autostereoscopic screen 10), the light thus transmitted by the blade being collected on the other side of the blade to generate a representation or an image A 111 of the object B 101 identical to the object B 101. The two micro-mirror matrices 22 and 23 are protected by layers 21 and 24 composed for example of borosilicate. Each matrix comprises an arrangement of reflective mirrors 221, each mirror corresponding to a parallelogram.

illustrates a portion of the layers 22 and 23 of the micro-mirror blade 12, according to a particular and non-limiting embodiment of the present invention.

Each layer comprises a series of micro-mirrors arranged parallel to each other at regular intervals, for example according to a pitch of 0.3, 0.4 or 0.5 mm. Each micro-mirror has the shape of a parallelogram with a thickness equal or substantially equal to the pitch separating each micro-mirror. Each micro-mirror is made of transparent glass or plastic and a reflective surface. The micro-mirrors of layers 22 and 23 have for example the same height and the same thickness but possibly different lengths (a first length for layer 22 and a second length for layer 23). As shown in FIG. 3, the micro-mirrors of layer 22 are arranged perpendicular to the micro-mirrors of layer 23 so as to form straight micro-dihedra. According to this arrangement, each micro-mirror of layer 22 crosses one or more micro-mirrors of layer 23 as shown in FIG. 4, the reflecting surfaces of these micro-mirrors belonging to 2 different layers 22 and 23 being perpendicular to them. to each other.

illustrates a ray of light 400 passing through the micro-mirror plate 12, according to a particular and non-limiting embodiment of the present invention.

The light ray 400 is for example emitted by the autostereoscopic screen and comes from the object B 101. The light ray 400 is initially reflected by the reflecting part 411 (specular surface) of a micro-mirror 41 of the layer 23 facing the autostereoscopic screen. The reflected light ray is then reflected once again and in a second time by the reflecting part 401 (specular surface) of a micro-mirror 40 of the layer 22 facing the image plane. The micro-mirrors 40 and 41 are arranged perpendicular to each other, as well as their respective reflective parts. The angle of incidence of the light ray reflecting on the micro-mirror 41 is equal to the angle of emergence of the light ray reflecting on the micro-mirror 40. The light ray reflected by the micro-mirror 40 contributes to the generation of the image of the object B 101 in the image plane 11. A multitude of light rays emitted by the autostereoscopic screen thus cross the plate 12 by being reflected on the micro-mirrors of the layers 22 and 23 to form the image 111 on the image plane 11. The micro-mirror plate 12 acts as a projection surface with a ratio of 1:1, i.e. there is no magnification or reduction the size of image 111 relative to object 101.

illustrates a first example of an autostereoscopic screen 50, namely a parallax barrier stereoscopic screen, included in the display device of FIG. 1, according to a particular and non-limiting example embodiment of the present invention.

The parallax barrier stereoscopic screen comprises a screen 501 of the LCD (Liquid Crystal Display) or OLED (Organic Light-Emitting Diode) type or in French “organic light-emitting diode”) for example associated with a filter 502 forming a parallax barrier. The application of a parallax barrier 502 in front of the screen 501 makes it possible to block certain rays originating from the pixels of the screen 501 in order to reproduce a stereoscopic display. The parallax barrier 502 is for example composed of an opaque black filter and small pinholes allowing certain light rays from the pixels of the screen 501 to pass. A distance of a few millimeters separates the parallax barrier 502 from the screen 501, so that an observer looking at a small hole in the parallax barrier does not see the same pixel of the screen with his right eye and his left eye. According to a variant, the small pinholes are replaced by vertical slits, to generate different views along the horizontal axis only. Such a technique makes it possible to reproduce a 3D effect from a 2D image.

illustrates a second example of an autostereoscopic screen 60, namely a stereoscopic screen with a lenticular array, included in the display device of FIG. 1, according to a particular and non-limiting example embodiment of the present invention.

The lenticular array stereoscopic screen comprises a screen 601 of the LCD (Liquid Crystal Display) or OLED (Organic Light-Emitting Diode) type or in French French "organic light-emitting diode") for example associated with an array of lenses 602. The application of the lenticular array 602 in front of the screen 601 makes it possible to deflect the rays coming from the pixels of the screen in order to reproduce a stereoscopic display. The lenticular array 602 is for example composed of a regular grid of small spherical lenses. Each lens covers an area of several pixels of the screen 601 and will deflect the direction of the light emitted by the covered pixels. Each lens can be seen by the observer as a 3D pixel, where the light emitted by a lens in a given direction always comes from a single pixel, but it comes from a different pixel depending on the direction of observation chosen. Consequently, an observer looking at a lens of the 3D screen does not see the same pixel of the screen 601 between his left eye and his right eye, although both of his eyes are staring at the same lens. According to a variant, the lenticular array 602 comprises cylindrical lenses instead of spherical lenses, which makes it possible to deflect the rays only along the horizontal axis. Such a technique makes it possible to reproduce a 3D effect from a 2D image.

Of course, the invention is not limited to the embodiments described above but extends to a dashboard integrating such a display device.

The invention also relates to a vehicle, for example an automobile or more generally a land motor vehicle, comprising the device 1 of FIG. 1.

Claims (10)

Display device (1) for a vehicle, said device comprising an autostereoscopic screen (10) adapted for rendering at least one 3D image (101) and a micro-mirror slide (12), said micro-mirror slide mirrors (12) being inclined at a determined angle with respect to said autostereoscopic screen (10) so as to project said at least one 3D image (101) in an image plane (11) formed in front of said micromirror plate (12) with respect to a given point of view (100). Device according to claim 1, wherein said at least one 3D image (101) is masked from said given point of view (100), said at least one 3D image being rendered in an object plane located behind a plane comprising said micro-slide. mirrors (12) with respect to said given point of view (100). Device according to one of claims 1 and 2, wherein said image plane (11) is orthogonal to said object plane. Device according to one of claims 1 to 3, wherein said image plane (11) is at a distance from said micromirror plate equivalent to a distance between said object plane and said micromirror plate (12). Device according to one of claims 1 to 4, wherein said micromirror plate (12) comprises two micromirror arrays (22, 23) arranged perpendicularly to each other, each micromirror array -mirrors comprising a series of micro-mirrors arranged parallel to each other and arranged at regular intervals in said matrix. Device according to one of claims 1 to 5, wherein said determined angle is equal to 45 °. Device according to one of claims 1 to 6, wherein said autostereoscopic screen (10) is a lenticular array screen (60). Device according to one of claims 1 to 6, wherein said autostereoscopic screen (10) is a parallax barrier screen (50). Dashboard for a vehicle incorporating the display device according to one of claims 1 to 8. Motor vehicle comprising the display device according to one of claims 1 to 8.