DE102015205167A1 - Method and control device for operating an autostereoscopic field of view display device for a vehicle - Google Patents

Abstract

The invention relates to methods (1500) for operating an autostereoscopic field of view display (102) for a vehicle (100), the method (1500) comprising a step (1502) of adjusting. Thereby, an offset (700) is made between a right image (402) and a left image (404) of the field of view display device (102) using a convergent angle (702) between a right visual axis (502) of the right eye (704) and a left visual axis (502) of the left eye (708) of a viewer (108) of the field of view display device (102). The images (402, 404) are set off-balance as the visual axes (502) intersect in a projection plane (504) of the images (402, 404).

Description

State of the art

The present invention relates to a method for operating an autostereoscopic field of view display device for a vehicle, to a corresponding control device and to a corresponding computer program.

The WO 1998/035260 A1 describes holographic screens that can be described by means of a laser projector and integrated into the windshield.

The publication " Exploring Design Parameters for a 3D Head-Up Display; Broy; Höckh; Frederksen et al; Pervasive displays 2014 "Shows a stereoscopic head-up display.

Disclosure of the invention

Against this background, with the approach presented here, a method for operating an autostereoscopic visual field display device for a vehicle, furthermore a control device which uses this method and finally a corresponding computer program according to the main claims are presented. Advantageous embodiments emerge from the respective subclaims and the following description.

In a field of view display with one and the same image for the right and left eyes of a viewer, a parallax error results when the image is viewed with one or more objects located at a different distance. This double image is filtered out by the brain of the beholder by using one of the eyes for vision. It is necessary for filtering a significant effort of the brain.

In the approach presented here, a right-eye image and a left image are provided to the viewer's left eye to eliminate the parallax error. This creates a virtual image that can be arranged approximately freely in space. A spatial position of the image can be adjusted depending on a viewing distance of the viewer. In particular, a convergence angle between visual axes of the eyes can be evaluated.

A method for operating an autostereoscopic field of view display device for a vehicle is presented, the method comprising the following step:
Adjusting an offset between a right image and a left image of the field of view display device using a convergent angle between a right visual axis of the right eye and a left visual axis of the left eye of a viewer of the field of view display device, wherein the images are set off-balance when the visual axes are in a plane of projection of the pictures.

An autostereoscopic field of view display device can be understood as a head-up display or a windscreen or windshield display. In this case, the field of view display device is designed to display two images in a projection plane, of which a right image is visible only to the right eye of the viewer. A left image is only visible to the viewer's left eye. The right image is only visible in a right viewing area. The left image is only visible in a left viewing area. For example, a holographic element of the field of view display device may have a directional emission characteristic. An offset may be a distance by which the associated pixels of the right and left images are offset from each other in the projection plane.

In this case, the pixels assigned to one another may be mutually corresponding pixels of the left and right images, which were projected with the said offset on the projection plane. The offset thus denotes a distance by which the right image is shown shifted in relation to the left image. An offset-free representation of the right-hand and left-hand images can be understood to mean a representation in which the right-hand and left-hand images overlap (in particular completely) and thus the corresponding pixels of the right-hand image are imaged on the associated pixels of the left-hand image. The viewer may be a driver of the vehicle.

The method may include a step of determining a position of the images in the projection plane. The determination can be made using the visual axes and eye positions of the observer. In the setting step, moreover, the specific position can be set. The images can be moved together in the projection plane without changing the offset. As a result, head movements of the observer can be compensated.

The method may include a step of reading eye information from an eye detector of the vehicle. The eye detection device is designed to capture the eyes of the observer. The eye positions are mapped in a right and left eye position value. The visual axes are in a right and left viewing direction value displayed. The convergence angle can be determined from the line of sight values and the eye position values. This allows the eye information to be processed in real time. The offset can be adjusted so fast.

The offset can be adjusted within an observer-dependent comfort range. Within the comfort zone, the viewer can combine both images to a spatial visual experience with a little effort. As a result, a slight burden on the viewer can be achieved.

The method may include a step of adjusting the comfort range. In this case, comfort range can be adapted in response to an input of the user. The comfort range can be set depending on a load condition of the viewer. If the viewer is strained, the comfort range can be reduced. The viewer may enter and / or change a comfort range setpoint via a user interface.

The comfort range can be adjusted depending on a number of depth levels to be displayed. The comfort range can be reduced as a number of depth planes are increased. Objects can be displayed at different distances. An object is assigned a depth level. Several illustrated depth levels may be more strenuous to consider than a few illustrated depth levels. Therefore, the comfort zone within which the objects are displayed can be made smaller.

The comfort range can be changed depending on the user. The comfort range can be reduced when the viewer tires. As a result, a load on the viewer can be reduced. The viewer can recover in this way.

A fatigue of the viewer can be detected using the eye information. In particular, a lid closure frequency and, alternatively or additionally, a lid closure duration can be evaluated. The eye information can reliably detect whether the user is tired. When the user recovers, the comfort area can be increased again.

The approach presented here also creates a control unit which is designed to execute, to control or to implement the steps of a variant of a method presented here in corresponding devices. Also by this embodiment of the invention in the form of a control device, the object underlying the invention can be achieved quickly and efficiently.

In the present case, a control device can be understood as meaning an electrical device which processes sensor signals and outputs control and / or data signals in dependence thereon. The control unit may have an interface, which may be formed in hardware and / or software. In the case of a hardware-based design, the interfaces can be part of a so-called system ASIC, for example, which contains various functions of the control unit. However, it is also possible that the interfaces are their own integrated circuits or at least partially consist of discrete components. In a software training, the interfaces may be software modules that are present, for example, on a microcontroller in addition to other software modules.

Also of advantage is a computer program product or computer program with program code which can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory or an optical memory and for carrying out, implementing and / or controlling the steps of the method according to one of the embodiments described above is used, especially when the program product or program is executed on a computer or a device.

The approach presented here will be explained in more detail below with reference to the accompanying drawings. Show it:

1 a representation of a vehicle with a field of view display device;

2 a representation of a focused on a leading vehicle traffic scene from the driver's perspective;

3 a representation of a focused on a visual field display traffic scene from the driver's view;

4 a representation of a field of view display device with a control device for operating the field of view display device according to an embodiment of the present invention;

5 a representation of an autostereoscopic field of view display device with combiner according to an embodiment of the present invention;

6 a representation of an autostereoscopic windshield display according to an embodiment of the present invention;

7 a schematic representation of the relationship between an image offset and a convergence angle in an autostereoscopic visual field display according to an embodiment of the present invention;

8th a schematic representation of the relationship between an image offset and a virtual image distance in an autostereoscopic visual field display according to an embodiment of the present invention;

9 a representation of a vehicle with a field of view display device according to an embodiment of the present invention;

10 an illustration of a traffic scene from the driver's perspective in a field of view display device according to an embodiment of the present invention;

11 a representation of a comfort zone in a relationship between a virtual image distance and a projection distance in a field of view display device according to an embodiment of the present invention;

12 a representation of a reduced comfort zone in a relationship between a virtual image distance and a projection distance in a field of view display device according to an embodiment of the present invention;

13 a flowchart of a method of operating an autostereoscopic visual field display device according to an embodiment of the present invention; and

14 a representation of an operation of a method for operating an autostereoscopic visual field display device according to an embodiment of the present invention.

In the following description of favorable embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and similar acting, with a repeated description of these elements is omitted.

1 shows a representation of a vehicle 100 with a field of view display device 102 , The field of view display device 102 is as a windscreen display 102 executed. This will be a real picture 104 an information to be displayed in the windscreen 106 of the vehicle 100 generated. The picture 104 is in the field of view of a viewer 108 , here the driver 108 of the vehicle 100 generated.

In a windshield display 102 or a separately integrated in the vehicle, superimposed with the driving scene transparent display 102 the displayed picture appears 104 on the display 102 as a real picture 102 in the area of the windscreen 106 or the separate glass or plastic disc and not like a HUD at a greater distance (greater than 1.8 m) as a virtual image. This is compared to the HUD when reading the image content on the windshield display 102 a stronger refocusing (accommodation) and turning (convergence) of the driver's eyes 108 from the driving scene to the windshield display 102 required. If the driver 108 When looking at the driving scene, the respective optical axes of his eyes are nearly parallel, so objects located in the vicinity (less than ten meters) are perceived twice. If the nearby object now consists of one, on a transparent display 102 displayed image content 104 , this appears twice and may be disturbing.

2 shows a representation of a on a preceding vehicle 200 focused traffic scene 202 from the driver's point of view. The traffic scene 202 is from the perspective of the driver in 1 shown. The driver looks through the windshield 106 forward to the traffic scene 202 , The right eye and the left eye of the driver are on the vehicle in front 200 focused. However, both the right eye and the left eye capture the image 104 in the windshield 106 , This will make the picture appear 104 as the right appearance 204 and left dummy image 206 double.

3 shows a representation of a on a visual field display 102 focused traffic scene 202 from the driver's point of view. The traffic scene 202 corresponds to the traffic scene in 2 , In contrast, the right eye and the left eye are here on the picture 104 focused. However, both the right eye and the left eye detect the vehicle ahead 200 , As a result, the preceding vehicle appears 200 double.

In 1 is a windshield display 102 illustrated with exemplary image content 104 , in this case a digital speedometer 104 , Consider the driver 108 the driving scene, ie distances in the range of about 10 m to 500 m, this image content appears 104 twice as it is in 2 is shown. On the other hand, he looks at the image content 104 the windshield display 102 , the underlying driving scene appears 200 double, as in 3 , This effect results in windshield displays 102 Too frequent switching of the eyes between distance and near vision, which is tiring in the long term.

Becomes a picture content 104 on a windshield display 102 shown, this typically appears twice when the driver 108 objects 200 the driving scene 202 considered. In this case, the preceding vehicle 200 , The recognition of the image content 104 the windshield display 102 in the peripheral field of view is made more difficult. On the other hand, he looks at the (monoscopically displayed) image content on the windshield 106 he sees the driving scene 202 double.

In a transparent display 102 , which is placed close to the primary field of view, arises because of the small image distance the problem that the driver 108 if, for example, he is driving ahead 200 , so on the display 102 drop by, the picture content 104 the transparent display 102 sees twice. Because of the convergence are the pictures 104 laterally offset from one another. This bothers a lot when the image content 104 on the transparent display 102 close to the driving 202 are synonymous and no sensible reading in the peripheral field of view - so to speak without looking directly on it - because the image content 104 just appear twice.

4 shows a representation of a field of view display device 102 with a control unit 400 for operating the field of view display device 102 according to an embodiment of the present invention. As in 1 is the field of view display device 102 in a vehicle 100 installed. In contrast, the field of view display device 102 here as an autostereoscopic head-up display 102 educated. The head-up display 102 projects a right picture 402 for the right eye of the beholder 108 and a left picture 404 for the viewer's left eye 108 , The projected images 402 . 404 be on an imager 406 of the head-up display 102 generated and via an optic 408 in the windshield 106 mirrored. From the windshield 106 become the pictures 402 . 404 in a viewing area 410 redirected, in which the eyes of the beholder 108 are located. The pictures 402 . 404 be from the controller 400 prepared to a picture content 412 for the viewer 108 spatially appear at a predetermined distance. For this purpose, the viewer is detected by a detection device 414 recorded and determined in particular a position and viewing direction of the eyes. Based on the positions and gaze directions of the eyes, there is an offset between the right image 402 and the left picture 404 determined to achieve the spatial effect.

In the present case, it is an autostereoscopic head-up display 102 (HUD) with adaptive display range presented, the current comfort zone of the driver 108 considered in terms of depth representation.

The approach presented here focuses on a special deployment scenario of the autostereoscopic head-up display 102 (HUD) received. As an important aspect, it can be stated in this connection that the (virtual) projection distances differ significantly in the case of an LCD screen and in an autostereoscopic HUD. It can be a HUD 102 as see-through display or field of view display. This display (unit) 412 is set according to the tiredness condition of the user. This is done by means of eye tracking 414 the user's direction of vision and internal rotation of the user's eyes recorded as well as the temporal evolution of the vision and the duration determined and used to assess whether problems of the driver 108 with the representation of symbols on the display unit 412 present or presumed.

A head-up display 102 (HUD) is used to display driving-related information 412 (eg speedometer, navigation information, warnings and much more) in the field of vision 410 the driver 108 , The virtual picture 412 , in which the information is displayed, is superimposed with the real environment.

Basically there is a HUD 102 from a light source, an imager unit 406 and a visual appearance 408 , The light leaving the system falls on the windshield 106 or a combiner disc mounted behind her, is partially reflected by her and reaches the eye 410 the driver 108 that the virtual picture 412 in one by the optics 408 perceived distance and a likewise determined by this magnification in front of him.

As a light source z. As LEDs or laser diodes are used, the image content providing LCDs 406 backlighting. Alternatively, different projectors can be used. In the future, miniaturized projectors based on DMD, LCoS or laser technology can increasingly be used. The aim is also to realize a contact analog representation. This takes a very large volume of space in biocular design, in which both eyes see the same picture. The binocular variant, in which the two eyes are single, slightly different images 402 . 404 In addition to the additional functionality of stereoscopic depth perception ("3-D effect"), it promises great advantages in terms of robustness, installation space and costs.

Using an autostereoscopic HUD 102 (asHUDs) can provide driving-related information 412 be presented in 3D without the driver 108 an additional resource like one Shutter or polarized glasses needed. So the driver 108 also with head movement at any time a perfect picture 412 sees, requires an asHUD 102 a head tracking system 414 which is capable of the head and eye position 410 the driver 108 to analyze, and an appropriate tracking. In 4 is a system overview of a basic structure of an asHUD system 102 shown.

5 shows a representation of an autostereoscopic field of view display device 102 with combiner 500 according to an embodiment of the present invention. The field of view display device 102 is like in the 1 to 4 installed in a vehicle. The imager 406 is illuminated by a light source. On the imager 406 the right picture and the left picture are generated. The combiner 500 reflects a reflection of the imager 406 towards the eyes of the beholder 108 , The combiner 500 is here at a lower edge of the windshield 106 arranged. The combiner 500 is thus below Sehachsen 502 the eyes of the beholder 108 when he sees into the distance. In other words, the combiner 500 in a peripheral field of view of the viewer 108 arranged. For the viewer 108 creates a virtual picture 504 in a projection plane 504 in the area of the windscreen 106 ,

In 5 an embodiment is shown in which a directionally radiating holographic projection screen 406 , which was sunk in the dashboard, over a flat glass pane 500 (or combiner disc) is mapped. Such an embodiment has the advantage that the system 102 regardless of the windshield 106 is usable and the picture as a virtual picture 504 something behind the windshield 106 is perceived as pleasant due to the increased image distance by the user.

In another embodiment, not shown, the image is projected directly onto a separate combiner disc, which then z. B. has a photopolymer layer with holographic scattering function. This eliminates the advantage of the extended image distance compared to the windshield display, but the system is space-saving and less complex, since it consists of fewer components.

Also, a variant of the in 5 displayed "Einspiegelungsanzeige 102 "imaginable, when the picture is not a separate disc, but directly over the windshield 106 is reflected. Such an embodiment has the advantage that no additional components need to be installed in the dashboard and thus no possibly interfering edges of the separate combiner 500 are visible. At low windshield curvature emerges even in such an embodiment, the user rated as acceptable image.

The stereoscopic display 102 can also be used as combiner indicator 102 be realized, as shown in this figure. A stereoscopic display 102 , which also in this form a holographic projection display 406 is also based on such a combiner display 102 realize. In this case, the holographic projection display 406 not transparent and is via a flat combiner 500 displayed. The image of the stereoscopic display 406 appears as a virtual image 504 , This has the advantage of a slightly larger image distance to the driver's eyes than in the embodiment described below.

6 shows a representation of an autostereoscopic windshield display 102 according to an embodiment of the present invention. The windshield display 102 can also be used as a visual field indicator 102 be designated. Unlike the field of view display in 5 Here are the right picture and the left picture in a projection area 600 or the projection plane generated in the windscreen 106 is integrated. Two projectors 602 project one of the pictures from below into the projection area 600 , In the projection area 600 is a holographic foil 604 in or on the windscreen 106 arranged. The foil 604 forms a right viewing area 606 for the right eye and a left viewing area 608 for the viewer's left eye 108 from. In the right viewing area 606 the right picture is visible, in the left viewing area 608 the left picture is visible. Through lateral movements of the projectors 602 can the viewing areas 606 . 608 sideways with the viewer 108 be moved.

In other words, a stereoscopic windshield display 102 presented with dynamic convergence adjustment.

A preferred embodiment of the transparent display 102 is the in 6 illustrated windshield display 102 , This is a photopolymer film 604 which realizes a holographic scattering function in or on the windshield 106 laminated. By suitable combination with two separate image projectors 602 Autostereoscopic image content can be generated as shown.

Shown is an embodiment of an autostereoscopic windshield display 102 , The dashed area 600 provides the usable ad space 600 that is from two projectors 602 is illuminated. The holographically realized transparent display 600 bows that from the first projector 602 illustrated picture in the first eyebox 606 that of the second projector 602 pictured image in the second eyebox 608 , By lateral movements of the projectors 602 can the lateral position of the eyeboxes 606 . 608 be changed to track lateral head movements.

7 shows a schematic representation of the relationship between an image offset 700 and a convergence angle 702 in an autostereoscopic visual field display 102 according to an embodiment of the present invention. Here is the field of view 102 in a vehicle 100 installed and a driver of the vehicle 100 looks through the field of view display 102 to a preceding vehicle 200 , Because the right eye 704 the driver at an eye relief 706 from the left eye 708 is removed, point the visual axes 502 the eyes 704 . 708 to each other the convergence angle 702 on when both eyes 704 . 708 on the same point 710 are directed. If the right picture 402 and the left picture 404 spatially at the point 710 should appear, is the image offset 700 between the right picture 402 and the left picture 404 depending on a viewing distance 712 between the eyes 704 . 708 and the pictures 402 . 404 , a distance 714 between the eyes 704 . 706 and the point under consideration 710 as well as the eye relief 706 ,

The convergence angle 702 Theta is the angle 702 between the optical axes 502 of the left 708 and the right one 704 Eye, let s be the distance 712 from the driver's eyes 704 . 708 to the windshield 106 and d is the disparity 700 , ie the offset 700 the stereoscopic on the windshield 106 shown pictures 402 . 404 which is presented to an object 710 in distance 714 z appear.

8th shows a schematic representation of the relationship between an image offset 700 and a virtual image distance 714 in an autostereoscopic visual field display 102 according to an embodiment of the present invention. The field of view indicator 102 corresponds essentially to one of the field of view displays in the 4 to 6 , The pictures 402 . 404 are in the same projection plane 504 arranged. Shown is on two examples, as with identical offset 700 , identical viewing distance 712 , but each with different signs, different virtual image distances 714 result.

In the first example is the right picture 402 arranged to the right of the left picture. The right eye 704 look at the right picture 402 , The left eye 708 look at the left picture 404 , This creates for the viewer the impression, the virtual image 412 Be further away than the pictures 402 . 404 actually are.

In the second example is the right picture 402 arranged to the left of the left image. The right eye 704 continues to look at the right picture 402 , The left eye 708 continues to look at the left image 404 , This creates for the viewer the impression, the virtual image 412 be between the viewer and the pictures 402 . 404 arranged.

In other words, in 8th the principle of stereoscopic 3-D-vision with indication of the sizes virtual screen distance 712 (VSD) and virtual image distance 714 (VID) for the crossed (right) and uncrossed (left) visual situation.

The imaging optics sets the virtual screen distance 712 (VSD) of the system 102 firmly. By a horizontal offset 700 d of the two frames 402 . 404 on the display or on the virtual screen distance 712 VSD can be the distance 714 (virtual image distance VID), in which the driver the picture 412 sees, choose. The parameters Virtual Canvas Distance 712 VSD and virtual image distance 714 VID are in 8th presented for the crossed and the uncrossed visual situation. The virtual image distance 714 VID is over

where a is the interpupillary eye relief 706 the driver stands. The sign in the denominator determines whether the picture 412 in front of or behind the virtual screen distance 712 VSD lies. The system 102 is able to look at the eye relief 706 adapt to allow the driver the picture information 412 at the desired distance 714 can perceive.

Because the eye relief 706 the driver is an indispensable information that the system 102 needed to view the picture 412 To realize that they are for the respective driver at the intended distance 714 appears, is the system 102 from the outset able to the eye relief 706 to measure the driver and the presentation 402 . 404 adjust accordingly. Take into account, for example, the size of the driver with respect to the look-down angle. The camera used for the head tracking is therefore also used to determine this information and the image representation 402 . 404 is customized to the driver. In addition, the driver can store personal preferences regarding brightness, color, contrast or comfort zone.

9 shows a representation of a vehicle 100 with a field of view display device 102 according to an embodiment of the present invention. The field of view display device 102 essentially corresponds to an image display device, as in the 5 and 6 is shown. The field of view display device 102 so here is a windshield display 102 or a windscreen display 102 , The driver 108 becomes a right picture 402 for the right eye 704 and a left picture 404 for the left eye 708 in the windshield 106 or windscreen 106 appears. The pictures 402 . 404 have an offset 700 to each other, as the driver 108 the driving scene in front of his vehicle 100 considered and therefore the visual axes of the eyes 704 . 708 behind a projection plane of the pictures 402 . 404 cross. The pictures 402 . 404 are shown distorted in perspective, from the perspective of the driver 108 to get undistorted pictures.

The transparent display device 102 can be realized by volume holograms. The vehicle 100 has a driver tracking system that shows the driver's line of sight 108 can capture.

To avoid double vision, the use of a stereoscopic windshield display 102 or a separately installed stereoscopic transparent display 102 in conjunction with a dynamic disparity adjustment system based on a real-time converged angle of the eyes 704 . 706 the driver 108 presented.

This requires a sight-tracking system that includes at least the two cases "driver 108 looks at the driving scene "and" driver 108 looks at the picture content 402 . 404 the transparent display 102 "can distinguish reliably and in real time." considers the driver 108 the driving scene, the disparity 700 between each for the left 708 and rights 704 Eye on the windshield display 102 displayed image content 402 . 404 adjusted so that double images are minimized. This corresponds to a stereoscopic shift of the image content 402 . 404 into the level of consideration of the driver 108 , Turns the driver 108 however, his view of the picture content 402 the windshield display 102 , these are not displayed stereoscopically, so the driver 108 This display as any other vehicle display can also read as usual.

Additional eye tracking is required to even with lateral head movements of the driver 108 to maintain the autostereoscopic effect.

It becomes a reading on a windshield 106 stereoscopically displayed image contents 402 . 404 without double image allows. The reading can be done without the convergence adjustment of the eyes required when reading conventional vehicle displays (eg instrument cluster) 704 . 708 respectively. This results in a time and comfort gain when reading the image content 402 . 404 , which ultimately improves driving safety. With appropriate resizing of the image contents 402 . 404 the windshield display 102 These can also be perceived and read in the peripheral field of view, so to speak, without looking directly. The size of the content presented 402 . 404 can then be adjusted according to the lower eye resolution in the peripheral field of view.

In 9 is an autostereoscopic windshield display 102 shown the same image content 402 . 404 as in 1 , but stereoscopically. The left 708 and rights 704 Eye of the driver 108 looks in each case one of the two objects shown offset to one another 402 . 404 , The autostereoscopic presentation does not create a double image when the driver 108 looking at the driving scene.

10 shows a representation of a traffic scene 202 from the driver's point of view in a field of view display device 102 according to an embodiment of the present invention. The traffic scene 202 essentially corresponds to the traffic scene in the 2 and 3 , Here's how the driver is in 9 although he captures the right image with the right eye and the left image with the left eye, a common undistorted virtual image 412 sees that between the preceding vehicle 200 and his vehicle 100 seems to float.

Becomes the image content 402 . 404 on the windshield display 102 shown stereoscopically, the image content appears 402 . 404 not double when the driver objects 200 the driving scene 202 considered - in this case, the preceding vehicle 200 , Thus, image contents can be used in this type of presentation 402 . 404 be read in the peripheral field of vision and do not appear annoying.

One solution to this problem is the presentation of autostereoscopic image content 402 . 404 that if the driver 108 not on the transparent display 102 looks so represented that they can be read at least in the peripheral field of view. If he looks directly at this image content or the ad, the Autostereoscopic display switched off because it would not be pleasant to the eye due to the small image distance.

The 11 and 12 show representations of comfort zones 1200 in the context of a virtual image distance 714 and a projection distance 712 or the viewing distance 712 in a field of view display device according to an embodiment of the present invention. It is in 11 the comfort zone 1200 for a single virtual image. In 12 is the comfort zone 1200 shown for multiple virtual images, with the virtual images at different distances 714 are shown. Within the comfort zone 1200 75% of the viewers regard the viewing of picture content as pleasant. The comfort zone 1200 starts at a minimum distance 1202 and ends at a maximum distance 1204 from the viewer. In the aforementioned publication "Exploring Design Parameters for a 3D Head-Up Display", studies were described in which the boundaries of the comfort zone described here only as an example were examined in more detail.

The comfort zone 1200 grows with increasing viewing distance 712 , For simultaneously displayed images in several distances is the comfort zone 1200 smaller than a single image. In addition, the minimum distance shifts 1202 in the case of several images compared to the individual image to larger image distances 714 while the maximum distance 1204 reduced.

In 11 is the comfort zone 1200 depending on the virtual screen distance 712 VSD and the virtual image distance 714 VID for representing a virtual 3-D object. The comfort zone 1200 represents 75% of the subjects. In the area adjacent to the comfort zone 1200 50% of the subjects are still within their comfort zone.

In 12 is the comfort zone 1200 depending on the virtual screen distance 712 VSD and the virtual image distance 714 VID for representing three virtual 3-D objects (front, middle, back). The middle area 1200 represents the comfort zone of 75% of the subjects. In the adjacent areas are still 50% of the subjects within their comfort zone.

Specifically, in the aforementioned publication "Exploring Design Parameters for a 3D Head-Up Display" a comfort zone 1200 using sample values for the relationship between virtual image distance VID 714 and virtual screen distance VSD 712 described for the HUD application. Continue to be the front 1202 and back border 1204 the comfort zone 1200 explained in more detail. At the same time systems with several (virtual) projection distances are used 714 addressed.

Apart from the in 8th described relationship, the 3-D perception of each individual person is individually different. So every person has an individual area in which the virtual image distance 714 VID at a given virtual canvas distance 712 VSD, in which a comfortable 3-D vision is possible for him. This area can be used as a comfort zone 1200 be designated. The comfort zone 1200 is significantly limited by criteria of accommodation-convergence conflict. Will the comfort zone 1200 exceeded, the driver may feel sensation and discomfort (eg, eye pain, headache). Under certain circumstances, the desired 3-D perception is no longer possible.

Any kind of physical malady, as well as loss of perception of the driving-relevant information presented by the asHUD, can be a risk on the road and endanger both the safety of the driver and all other road users.

The approach presented here is an autostereoscopic HUD with an adaptive display area 1200 presented. This display area is adapted not only to the respective driver, but also to his current physical and / or psychological situation. This avoids that the 3-D representation outside the (current) comfort zone 1200 the driver is located, which guarantees a pleasant for the driver perception and eye pain, headache or discomfort are avoided, which leads to an increase in driving safety and fun factor.

The asHUD uses the head tracking data and other information collected by the head tracking camera to size the display area 1200 and the number of depth levels in which image content is displayed adaptively to the current comfort zone 1200 to adapt to the driver. This results in a reduced negative influence of 3-D imaging, which can cause symptoms such as headache, eye pain, malaise. Furthermore, there is a reduction in the risk that the image information can not be merged. On a prolonged life can be done because z. As in fatigue the comfort zone 1200 is limited, whereas without an adaptive adjustment of the driver would have to turn off the system, since the perception in the presentation for him becomes uncomfortable.

Furthermore, there is less fatigue of the driver, since the display is adapted to him so that it is the least strenuous for him. The display area 1200 can be adjusted individually for crossed and uncrossed visual situation, ie front 1202 and rear 1204 Limit of the display area 1200 can be changed separately. Driver with a particularly large comfort zone 1200 You can also use these. The system can adapt to different drivers / situations. The result is an increase in the experience factor, an increase in safety and an increase in comfort.

The comfort zone 1200 is strong on the chosen virtual screen distance 712 VSD dependent. Per virtual screen distance 712 VSD results in a specific area 1200 the virtual image distance 714 VID, in which information can be displayed so that it is pleasant to the driver. This area 1200 depending on the virtual screen distance 712 VSD was examined. The results are in the 12 and 13 presented qualitatively. In " Exploring Design Parameters for a 3D Head-Up Display; Broy; Höckh; Frederksen et al, Pervasive Displays 2014 "Are shown more accurate values. The comfort zone 1200 represents the pleasing area of 75% of the subjects. Therefore, depending on the virtual canvas distance used in the asHUD 712 VSD also a suitably adapted area 1200 within the lower 1202 and upper 1204 Limit of the virtual image distance 714 VID, VlDmin and VlDmax are selected for the presentation of the information. For systems with multiple virtual screens 712 VSDs or even a resizable virtual canvas distance 712 VSD can also work when switching or changing the virtual screen distance 712 VSD to a corresponding adjustment of the area used for the representation 1200 the virtual image distance 714 VID to be respected.

The comfort zone 1200 is not only about the virtual screen distance 712 Dependent on the VSD, but also on the number of virtual image planes with different virtual image distances 714 VIDs used for the ad. The here presented asHUD also has an adaptation of the comfort zone 1200 depending on the image content, in particular the number of virtual image planes used.

The and 12 represent only the magnitudes and the general course of the comfort zone depending on the VSD. The concrete figures are situation-specific, details of the underlying studies can be found in the above-mentioned publication.

Furthermore, these are in the 11 and 12 empirically determined values are not valid for every driver, there are big individual differences. In addition, the comfort zone can be 1200 change a driver. Factors such as fatigue, contrast, duration of use, visual defects etc. play a major role here. Therefore, in another embodiment of the system, not only the virtual screen distance as described above 712 VSD and the number of virtual levels, but also an individual, time-varying condition of the driver.

In a simple embodiment, the driver has the option of giving feedback to the system if its comfort zone 1200 is violated, that is, if he feels the current presentation as unpleasant. The input device can be z. B. from a knob, from controls, steering wheel buttons, a touch screen or a voice or gesture control. This can be a simple input, in that the driver only measures the size of the comfort zone used 1200 zoom in or out, or a more complex input that allows the driver, the front 1202 and the back 1204 Limit of the virtual image distance 714 Directly adjust the VID and / or the maximum number of depth levels using the input device.

In another embodiment, the system is more complex. The system automatically detects when the comfort zone 1200 of the driver is exceeded, and automatically adjusts them.

The observation of the driver allows the display area 714 to the current comfort zone 1200 to adapt to the driver. For this purpose, information is obtained from the camera images of the head-tracking system.

General fatigue can be determined by changing the steering behavior or the camera image of the driver's face. Here are z. Gaze, eyelid frequency, eyelid duration, percentage eye closure or yawning. From the information of the steering angle sensor and the head tracking camera thus the fatigue state of the driver can be detected. If fatigue is present, it is assumed in this case that a simplified representation with reduced display range 714 and less depth levels is appropriate.

The reduction of the display area can be z. In increments of 20% with respect to the front limit 1202 (VIDmin is increased by 20%) and in steps of 10% in terms of the rear limit 1204 (VIDmax is reduced by 10%) be managed. At the same time, the number of depth levels used can decrease by one. After each step, a new evaluation of the driver behavior and possibly a further step takes place. If a condition is reached in which the driver can easily handle the HUD display again, it is initially maintained. Should the driver's continued observation indicate that reading the display is becoming increasingly easy for him, the system may change his display range 1200 in the same steps in the other direction again increase.

The proposed system is not only able to detect the driver's line of sight by means of eye tracking, but also to deduce from the degree of internal rotation of the two eyes the convergence plane of the driver's visual axis. This makes it possible to recognize the duration of the viewing of the image content and its change over time. In order to be able to capture the image content, it is necessary for both the viewing direction and the convergence plane of the visual axes to match the object shown. If it takes more and more time for the driver to reach this consistent viewing condition, then it can be assumed that there are increasing merger difficulties. The system records how long the driver needs, until the viewing direction and convergence plane are adjusted and how long he looks at a displayed object. Should this time be untypically high for the respective driver or exceed a previously defined absolute value or increase significantly with the service life, the system reacts as described above with a reduction of the comfort zone 1200 and the number of depth levels used.

Should the driver still be unable to fuse the images, the 3-D mode will be disabled. The system then works as a 2-D HUD and can use the perspective view. After the next break or at the request of the driver, the 3-D mode is switched on again. If necessary, the driver uses the input device described above.

The system compares the data obtained from the driver observation with the image content displayed at the time. This comparison shows what information currently interests the driver most. This can then be placed, for example, in the center of the visual field and, if it is not displayed contact analog, in the middle of the display area, wherein each z. B. observed over a minute and then can be reacted to it.

In summary, it can be said that the system presented here is capable of determining the depth position 714 adjust the image content and stagger the depth levels used more closely and reduce their number if the entirety of the information described above indicates to this system that image content is currently out of the driver's comfortable range 1200 are located. The goal here is that only the individual instantaneous comfort zone 1200 the driver is used. If, for example, the driver has been on the road for some time and, in addition or alternatively, it is getting dark and the driver is getting tired, this is his comfort zone 1200 get smaller. It may be the driver then increasingly difficult, with a small virtual image distance 714 Recognize VID displayed information. In this case, he needs more time to read this information. The system reacts to this and increases the smallest used virtual image distance 1202 VID until the system can no longer detect any driver's difficulty in using the asHUD with adaptive display area.

13 shows a flowchart of a method 1500 for operating an autostereoscopic field of view display device according to an embodiment of the present invention. The procedure 1500 has a step 1500 of adjusting an offset between a right image and a left image of the field of view display device. In this case, the offset is adjusted using a convergence angle between a right visual axis of the right eye and a left visual axis of the left eye of a viewer of the field of view display device. The pictures are in a partial step 1502 adjusted without offset when the visual axes intersect in a projection plane of the images.

In one embodiment, the method 1500 one step 1504 of determining. The step 1504 has several sub-steps 1504 on. In a first step 1504 a viewing direction of the viewer is determined. In a second step 1504 the convergence angle is determined. In a third step 1504 an eye position is determined.

In determining the viewing direction, a distinction is made as to whether the viewer is looking into the distance or whether the viewer is looking at the field of view display. In determining the convergence angle, the visual axes of the right and left eyes are evaluated taking into account an eye distance of the eyes. In determining the eye position, the eye relief and a relative position of the eyes are determined to the field of view display device. When the viewer looks into the distance, the offset becomes one step 1506 calculated using the convergence angle and in step 1502 of setting the images stereoscopically. When the viewer looks at the visual field display, in step 1502 of setting the images without offset or monoscopic shown.

In a further sub-step 1506 In addition, in calculating, a position of the images on the visual field display is calculated to compensate for head movements of the observer.

In step 1502 of setting, the image contents are further processed for the field of view display device.

The flowchart shows an exemplary embodiment of the display system according to the invention. An unspecified driver observation system detects the viewing direction, the above-described convergence angle theta, and the driver's eye position. If the driver has focused his attention on the transparent display, its contents are displayed monoscopically. If the driver observes the driving scene, the contents of the transparent display are shifted according to the given formula d ≈ θ · (z-s) by adjusting the disparity in the driving scene to eliminate otherwise occurring double images. Furthermore, the driver's eye position is determined in order to correspondingly dynamically adapt the image contents stereoscopically shifted in the driving scene in the event of lateral head movements of the driver in their position in accordance with the depth reference motion parallax.

14 shows a representation of an operation of a method for operating an autostereoscopic visual field display device 102 according to an embodiment of the present invention. This is the field of view display device for a viewer 108 or driver 108 a right picture 402 for the right eye and a left image 404 ready for the left eye. The viewer 108 is through a camera 414 recorded by a driver monitoring system. The camera 414 makes a camera picture 1600 or video information 1600 ready. The camera picture 1600 is in a control unit 400 evaluated. In this case, in a first evaluation 1602 the camera picture 1600 evaluated to a picture content for the field of view display device 102 adapt. In doing so, especially eye positions 1604 and visual axes 1606 the eyes evaluated and provided for further processing.

In a second evaluation device 1608 becomes the camera image 1600 evaluated to a comfort zone 1610 the viewer 108 to recognize. Here, on the basis of physical reactions becomes a state of stress of the viewer 108 determined. The comfort zone 1610 depends on the load condition.

Using the eye positions 1604 and visual axes 1606 will be in a facility 1612 for determining an offset 700 between the right picture 402 and the left picture 404 certainly. In a facility 1614 to adjust the offset 700 between the pictures by moving picture contents to be displayed to a position determined by the offset. This will be a right image information 1616 and a left picture information 1618 provided.

In a facility 1620 to adjust the right and left image information 1616 . 1618 using the comfort zone 1610 customized. If the offset 700 is outside the comfort zone, the offset is limited. The device 1620 provides a customized right image information 1622 and a customized left image information 1624 for the field of view display device 102 ready.

This results in a control loop in which the reaction of the observer 108 decisive for setting the comfort zone 1610 is.

In other words shows 16 the incorporation of the approach presented here into the functioning of an autostereoscopic head-up display 102 ,

In this case, the more complex embodiment can be combined with the simpler embodiment. The system 400 works automatically, but the driver can not only turn it off, but also manually adjust it to his needs as in the simpler embodiment.

In another embodiment, the automated system is designed as a learning system so that it learns and stores the individual drivers and their typical attitudes and fatigue. The ideal adaptation can thus take place faster and more smoothly.

It is a schematic representation of how the asHUD works 102 shown with comfort zone adjustment.

The embodiments described and shown in the figures are chosen only by way of example. Different embodiments may be combined together or in relation to individual features. Also, an embodiment can be supplemented by features of another embodiment.

Furthermore, the method steps presented here can be repeated as well as executed in a sequence other than that described.

If an exemplary embodiment comprises a "and / or" link between a first feature and a second feature, then this is to be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment either only first feature or only the second feature.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 1998/035260 A1 [0002]

Cited non-patent literature

• Exploring Design Parameters for a 3D Head-Up Display; Broy; Höckh; Frederksen et al; Pervasive displays 2014 [0003]
• Exploring Design Parameters for a 3D Head-Up Display; Broy; Höckh; Frederksen et al, Pervasive Displays 2014 [0088]

Claims (11)

Procedure ( 1500 ) for operating an autostereoscopic visual field display device ( 102 ) for a vehicle ( 100 ), the process ( 1500 ) comprises the following step: setting ( 1502 ) of an offset ( 700 ) between a right picture ( 402 ) and a left image ( 404 ) of the field of view display device ( 102 ) using a convergence angle ( 702 ) between a right visual axis ( 502 ) of the right eye ( 704 ) and a left visual axis ( 502 ) of the left eye ( 708 ) of a viewer ( 108 ) of the field of view display device ( 102 ), the images ( 402 . 404 ) can be set without offset when the visual axes ( 502 ) in a projection plane ( 504 ) of the pictures ( 402 . 404 ). Procedure ( 1500 ) according to claim 1, with a step ( 506 ) of determining a position of the images ( 402 . 404 ) in the projection plane ( 504 ) using the visual axes ( 502 ) and eye positions of the observer ( 108 ), wherein in the setting step ( 1502 ) further the specific position is set. Procedure ( 1500 ) according to one of the preceding claims, comprising a step of reading in eye information from an eye detection device ( 414 ) of the vehicle ( 100 ), which is adapted to the eyes ( 704 . 708 ) of the viewer ( 108 ), wherein eye positions in a right and left eye position value ( 1604 ) of the eye information and the visual axes ( 502 ) in a right and left viewing direction value ( 1606 ) of the eye information, wherein in step ( 1502 ) of adjusting the convergence angle ( 702 ) from the viewing direction values ( 1606 ) and the eye position values ( 1604 ) is determined. Procedure ( 1500 ) according to one of the preceding claims, wherein in step ( 1502 ) of adjusting the offset ( 700 ) within an observer-dependent comfort area ( 1200 ) is set. Procedure ( 1500 ) according to claim 4, comprising a step of adjusting the comfort range ( 1200 ), where the comfort range ( 1200 ) in response to an input of the user ( 108 ) is adjusted. Procedure ( 1500 ) according to one of claims 4 to 5, wherein in the step of adapting the comfort area ( 1200 ) is adjusted depending on a number of depth levels to be displayed, the comfort range ( 1200 ) is decreased as a number of depth planes are increased. Procedure ( 1500 ) according to one of claims 4 to 6, wherein in the step of adapting the comfort area ( 1200 ) is changed user-dependent, whereby the comfort range ( 1200 ) is reduced when the viewer ( 108 ) tired. Procedure ( 1500 ) according to claim 7, wherein in the step of fitting a fatigue of the observer ( 108 ) is detected using the eye information, in particular a lid closure frequency and / or eyelid closure time is evaluated. Control unit ( 400 ), which is designed to handle all steps of a process ( 1500 ) according to one of the preceding claims. Computer program adapted to perform all the steps of a method according to any one of the preceding claims. A machine-readable storage medium having a computer program stored thereon according to claim 10.

Images