DE102020108124A1 - Compact visor field of view display device with eyebox tracking - Google Patents

Abstract

The invention relates to a compact field of view display device which is designed to be fixed in place in a higher-level system, in particular on a headliner of a motor vehicle, comprising: a spatially compact projector system with two projector units, which are arranged symmetrically about a vertical center plane of the projector system and each to Generating a projection light beam bundle intended only for a user eye with a display content; is that each of the two projection light beams is reflected by the combiner pane to the associated eyebox area, so that a virtual display image into the field of vision of the user behind d the combiner pane is displayed; and a detection device which is designed to determine deviations of current user eye positions from the associated eyebox areas.

Description

Technical area

The invention relates to field of view display devices for generating a virtual display image which is superimposed into the field of view of a user and which are designed to be fixed in place in a higher-level system, in particular a motor vehicle.

Technical background

Conventional infotainment display systems in a motor vehicle are usually known either via flat screens (flat panel displays), such as in the instrument cluster, the central display or rear seat entertainment displays, or via head-up displays (HUD) Field of view display devices realized. The latter use a projection by means of a projection optics system typically integrated in the instrument panel of the vehicle via reflection on the windshield or a combiner pane arranged in front of it, for example to provide the driver with supportive display content, such as information about a current speed limit and the like, as a virtual display image to superimpose the real image of the surroundings in front of the vehicle or to display entertainment content in the field of vision of a vehicle occupant.

However, it is difficult to implement a large-area display with these known technologies: The integration of large-area flat screens in a motor vehicle is usually problematic due to the limited installation space. For the user, too, larger flat-panel displays in motor vehicles usually have a negative effect on the sense of space. An enlargement of a virtual display image area generated by conventional HUDs typically results in a correspondingly enlarged volume of the projector integrated in the instrument panel and associated problems with integration.

Furthermore, for example, are off DE 10 2017 208 028 A1 Display systems attached to the vehicle seat of the user or to his headrest are known, in which a display surface can be adjusted between a position of use in front of the user's face and a different parking position stowed on or in the seat. The indicated display surface can also be used as a reflection surface for a projection image, particularly in the case of a transparent design, so that visual information overlaying the real environment can be displayed (augmented reality). For this purpose, suitable projection devices can be attached in the seat or on a display element forming the display surface. With this attachment of the display system to the user seat, it is possible to cover almost the entire field of vision of the user with the display surface, but this can also entail certain restrictions for the available installation space or the achievable distances from the user's head.

Furthermore, for example, is off DE 10 2017 214 627 A1 a head-up system designed as a mobile device for vehicles is known, which comprises an image-generating display and a combiner mirror, which are tracked according to the head pose of a user, in particular a driver. For this purpose, the system has a holding device which can be moved by activation and which holds the display and the combiner mirror. The system is set up to continuously record a head pose of the user and to bring the combiner mirror and the display into a certain head-up pose by activating the holding device in such a way that the user is shown an image overlaying the surroundings. Specifically, the holding device comprises a frame on which the combiner mirror and the display are rigidly coupled to one another, ie always in the same constellation. This system can also take up space and thus make integration in a vehicle more difficult.

It is the object of the present invention to provide an alternative or improved field of view display device which, compared to this prior art, in particular with regard to the required installation space and / or user comfort, such as a viewing direction independence of the display or a change in the space around the user in a higher-level System, such as B. a motor vehicle, can be improved.

Disclosure of the invention

This object is achieved by a spatially compact field of view display device according to claim 1 and a vehicle equipped therewith according to the independent claim. Further refinements are given in the dependent claims. All in the claims and the following description for The additional features and effects referred to as the field of view display device also apply in relation to the vehicle, as well as vice versa.

According to a first aspect, a compact visual field display device is provided which is designed to be fixed in place in a higher-level system, for example on a headliner of a motor vehicle or any other land, air or water vehicle. In other words, the field of view display device is integrated in its higher-level system, e.g. B. integrated therein or subsequently assembled, state free of mechanical connections to a user, such as. B. an occupant of the vehicle.

The field of view display device is designed to fade in a virtual display image into the user's field of vision and for this purpose firstly comprises a spatially compact projector system with two projector units, which are arranged symmetrically around a vertical central plane of the projector system and each to generate one only for the left or only for the right user eye certain projection light beam are formed with a display content to be shown in the virtual display image. The named vertical center plane of the projector system can, for example, be aligned in a motor vehicle approximately parallel to a plane spanned by the vertical and longitudinal axes of the normal vehicle coordinate system.

Furthermore, the field of view display device comprises a combiner pane which is reflective on the user side and is transparent on the rear side, in particular at least partially in the visible spectral range (also referred to herein as a “visor”). The combiner pane is designed and fixed or fixable in an operating position defined with respect to the projector system below it at a predetermined horizontal distance in front of two two-dimensional eyebox areas, each intended for only one user eye, so that each of the mentioned two projection light beam bundles reflects from the combiner pane to the associated eyebox area so that the desired virtual display image is displayed in the user's field of vision behind the combiner pane. The spatial location, ie position / location and alignment, of the two eyebox areas in relation to the projector system results from the optical structure and the thereby defined beam path of an entire “visor unit” of the type set out here, which includes the projector system and the combiner pane. The mentioned horizontal distance can in particular be between 180 mm and 380 mm, more specifically between 230 mm and 330 mm, and for example be about 280 mm (cf. 1 and 2 ).

In order to achieve a projector arrangement that is as compact as possible, the size of the two eyebox areas, which are defined here as two-dimensional areas perpendicular to the direction of beam propagation of the respective projection light beam, can, for reasons explained in more detail below, be deliberately reduced to an elliptical area of just about 38mm by 25mm, for example the respective user eye can be limited (cf. 3 ). The two projector units therefore ideally each generate only a relatively small and sharply delimited area from which the virtual display image can be seen uncut with the respective user eye (the respective eyebox, characterized by the aforementioned two-dimensional eyebox area). The size of the respective eyebox area can, for example, primarily be determined by the diameter of a lens system used in the associated projector unit (cf. 2 ).

To enable a robust detection of whether the user's eyes are in said eyebox areas of the field of view display device, it further comprises a detection device which is designed to determine deviations of current user eye positions (i.e. positions of the two eyes of the user) from the associated eyebox areas. Various examples of a suitable detection device are given below. The determined deviations can, for example, be used in a suitable control unit, which can be part of the present field of view display device, for an automated adaptation of the eyebox areas of the field of view display device to the current user eye positions (as described in detail below) or alternatively, for example, to output a corresponding message to the user so that he can, for example, adjust his head position in a targeted manner. In any case, the deviations determined by the detection device can be used to reliably prevent the user from leaving the eyebox areas of the field of view display device without noticing it by moving his head etc., in particular so that he can always see the virtual display image in its best possible quality.

The present field of view display device enables a spatially compact and in a higher-level system, such as. B. a motor vehicle or aircraft, in a simple and at the same time ergonomic A projector system that can be integrated, for example, with which work, entertainment and / or AR (Augmented Reality) displays can be generated as a virtual display image. The combiner pane (visor) in its operating position is lower than the projector system and can be positioned in front of the user's eyes at a comfortable horizontal visor spacing that can basically be selected as desired, ie without restricting his sense of space.

With this arrangement, for example, a 35 ° × 20 ° virtual display image can be generated at a projection distance of approximately 2.5 m from the eyes of the user from a projector system with a volume in the range of approximately 2.5 L. In comparison, a projection unit known from conventional HUD systems, which uses a common beam path for both eyes of the user, would require an optical system with a volume of 8-10 L three to four times as large to display the same virtual display image. The resulting image size can in particular correspond to a 65-70 inch screen at a distance of 2.5 m with a resolution, for example, in the order of magnitude of 4000 pixels in the horizontal and / or vertical direction (4k resolution), that is to say, for example, as with a Flat screen TV of this size. (see. 6th ).

• - die gesamte Visoreinheit, die das Projektorsystem und die Combinerscheibe umfasst, in einer, zwei oder allen drei Raumdimensionen im übergeordneten System bewegt, d. h. in deren räumlicher Lage verändert, beispielsweise translatorisch verfahren und/oder rotatorisch verkippt, wird; und/oder
• - die Projektoreinheiten gemeinsam und/oder relativ zueinander im Projektorsystem bewegt, d. h. in deren räumlicher Lage in Bezug auf das Projektorsystem, insbesondere in Bezug auf dessen Mittenebene, verändert, beispielsweise translatorisch verfahren und/oder rotatorisch verkippt, werden; und/oder
• - die Combinerscheibe relativ zum Projektorsystem bewegt, d. h. in deren räumlicher Lage in Bezug auf dessen Mittenebene verändert wird, beispielsweise indem ein Mittelpunkt der Combinerscheibe translatorisch verfahren wird und/oder die Combinerscheibe um deren durch den genannten Mittelpunkt gehende Hoch- oder Querachse verkippt wird.

According to one embodiment, the field of view display device further comprises an eyebox tracking device which is designed and set up to determine a spatial location (ie a position and / or orientation, for example in relation to the projector system or to the higher-level system) of the two eyebox areas track current user eye positions by using the above-mentioned deviations that have been determined by the detection device by

• the entire visor unit, which comprises the projector system and the combiner disk, is moved in one, two or all three spatial dimensions in the higher-level system, ie its spatial position is changed, for example moved in a translatory manner and / or tilted in a rotary manner; and or
• the projector units are moved together and / or relative to one another in the projector system, ie their spatial position in relation to the projector system, in particular in relation to its central plane, is changed, for example moved in a translatory manner and / or tilted in a rotary manner; and or
• - The combiner disk is moved relative to the projector system, ie its spatial position is changed in relation to its center plane, for example by moving a center point of the combiner disk in a translatory manner and / or tilting the combiner disk about its vertical or transverse axis going through the said center point.

According to one embodiment, the detection device comprises one or more sensors, such as camera systems, time-of-flight sensors, structured light sensors, LIDAR and / or ultrasonic sensors, which are designed to detect a spatial area containing the eyebox areas (cf. . 4th ). The detection device is designed to determine current user eye positions from a user image captured by these sensors. For example, at least one of these sensors can sensibly be integrated in the visor unit, which comprises the projector system and the combiner pane.

In a further development of this embodiment, the field of view display device further comprises one or more marking light sources, in particular light-emitting diodes (LEDs), which are designed and arranged in the projector units in such a way that their respective marking light beam bundles through the optics of the visor unit into the eyebox areas, for example in their respective edge area , to mark the eyebox areas in the user image captured by the sensors, in particular focused (cf. 5 ). The user's face serves as a "projection surface" in which the mentioned markings of the eyebox areas are visible. The detection device is also designed to determine a current position of the eyebox areas based on the aforementioned marking in the user image captured by the sensors and to use the current position of the eyebox areas determined in this way when determining the above-mentioned deviations in the current user eye positions.

In particular, one or more of the marking light sources can be designed as infrared light sources, in particular infrared LEDs, so that their marking pattern projected onto the face of the user is invisible to the human eye. Correspondingly, one or more of the sensors are designed as infrared light sensors, for example infrared cameras.

In a specific configuration according to the embodiment mentioned, a user-side reflective surface of the combiner pane in its operating position is designed as a concave mirror that is symmetrical about the vertical center plane of the projector system, in particular a parabolic mirror, which for at least partial collimation of both projection light beam is formed and arranged. Furthermore, in the operating position of the combiner pane, the optical path length of the respective projection light beam between an optical output of the associated projector unit (which can be defined, for example, by the optical aperture of an optical element, such as a lens, last in the beam path of the projection light beam) and the concave mirror and / or approximately twice the focal length of the concave mirror between the concave mirror and the associated eyebox area.

In this case, the optics of the visor unit meet the condition for a 2f or 1: 1 image, if one z. B. presents an image of the aperture of the final projector lens at the optical output of the respective projector unit in the associated eyebox area through the concave mirror of the combiner pane. The marking light sources are arranged at the said optical output of the respective projector unit in such a way that they are imaged by the mentioned 1: 1 mapping in an edge area of the associated eyebox area for its marking.

In particular, the marking light sources can be permanently connected to the projector system or to the respective projector unit, for example by being permanently installed in its housing, in order to have a fixed position of the marking light sources relative to the position of the optics of the projector system and thus also a fixed relative position of the projected one Ensure marking pattern to the associated eyebox area. As an alternative or in addition, the marking light sources can be arranged around a lens aperture at the optical output of the respective projector unit, for example two, three or more marking light sources can be distributed along the respective aperture edge so that they can be moved through the optics of the visor unit into an edge area of the associated eyebox area Marking are mapped.

In particular, in the field of view display device of the type set out here, each projector unit can have a display for generating the display content to be transported by the associated projection light beam, as well as an optical imaging system, for example one or more lenses, which is used to display this display content in a real intermediate image that is in the beam path of the projection light beam is generated between the projector system and the combiner pane in its operating position.

According to one embodiment, the field of view display device further comprises a foldable housing in which the projector system is accommodated, the housing being spatially compact in its closed state and in particular being able to surround the projector system from all sides. In particular, when the housing is closed, the entire surface of the combiner disc can rest against its bottom side or form part of it and can be opened from said bottom side to a predetermined angle that corresponds to the operating position of the combiner disc. Alternatively or additionally, the housing can have a mirror wall that can be extended to a predetermined mirror distance from the projector system in the beam path of the two projection light beam bundles with a deflecting mirror facing the projector system, the two projection light beam bundles passing through the deflecting mirror in its operating position, defined by the predetermined mirror distance, onto a reflective surface of the combiner pane be steered to generate said virtual display image behind it.

This embodiment is characterized by a foldable housing mechanism around the spatially compact projector system, which enables optical components protruding from the projector system such as the deflection mirror and the combiner pane to be folded onto the housing or pushed into the housing outside of the operation of the field of view display device. As a result, for the entire field of view display device, in particular, a compact installation space without exposed components prone to injury, as well as easier retrofitting in a higher-level system, such as a motor vehicle, and / or a particularly aesthetic appearance can be achieved. In particular, such a field of view display device can therefore, for example, be attached to a roof lining in a motor vehicle without impairing the passenger compartment (at any position, for example, in the front or rear seat area).

• - einen Insassenraum, der nach oben zumindest teilweise von einem dem Insassenraum zugewandten Dachhimmel begrenzt ist; und
• - eine Blickfeldanzeigevorrichtung der hierin dargelegten Art, insbesondere gemäß der obigen Ausführungsform, die am Dachhimmel, insbesondere mit einer von der Bodenseite abgewandten Dachseite des faltbaren Gehäuses, befestigt ist.

According to a further aspect, a vehicle, in particular a motor vehicle or any other motor vehicle, aircraft or water vehicle, is provided, which comprises the following:

• - a passenger compartment which is at least partially delimited at the top by a headliner facing the passenger compartment; and
• a field of view display device of the type set out herein, in particular according to the above embodiment, which is attached to the roof lining, in particular to a roof side of the foldable housing facing away from the bottom side.

Figure list

• 1 eine perspektivische Seitenansicht einer Blickfeldanzeigevorrichtung der hierin dargelegten Art schräg von oben im Betrieb, wobei in beiden Projektoreinheiten aus Darstellungsgründen jeweils nur ein aus einem Displaymittenpunkt ausgehendes Teil-Strahlenbündel angedeutet ist;
• 2 eine perspektivische Seitenansicht der Blickfeldanzeigevorrichtung der 1, wobei in beiden Projektoreinheiten jeweils das gesamte Projektionslichtstrahlenbündel angedeutet ist;
• 3 eine Eyeboxebene der Blickfeldanzeigevorrichtung der 1 mit für beide Benutzeraugen vorgesehenen Eyeboxbereichen;
• 4 eine Seitenansicht der Blickfeldanzeigevorrichtung gemäß der 2 mit einem Beispiel für die Anordnung eines Kamerasystems, das als Sensor einer Detektionseinrichtung dient;
• 5 einige verschiedene perspektivische Ansichten eines Beispiels einer Anordnung von Markierungslichtquellen in den Projektoreinheiten; und
• 6 ein Kraftfahrzeug mit einer in dessen Insassenraum angeordneten Blickfeldanzeigevorrichtung der hierin dargelegten Art.

The above aspects of the invention and its embodiments and specific configurations are explained in more detail below with reference to the examples shown in the accompanying drawings. For reasons of clarity, the drawings are at least partially purely schematic: they can, but generally do not have to be understood as being true to scale. Show it:

• 1 a perspective side view of a field of view display device of the type set forth herein at an angle from above during operation, with only one partial beam of rays emanating from a display center point being indicated in each of the two projector units for reasons of illustration;
• 2 FIG. 3 is a perspective side view of the field of view display device of FIG 1 , wherein the entire projection light beam is indicated in each of the two projector units;
• 3 an eyebox plane of the field of view display device of 1 with eyebox areas intended for both user eyes;
• 4th a side view of the field of view display device according to FIG 2 with an example of the arrangement of a camera system that serves as a sensor of a detection device;
• 5 several different perspective views of an example of an arrangement of marking light sources in the projector units; and
• 6th a motor vehicle with a field of view display device of the type set forth herein arranged in its passenger compartment.

Description of embodiments

All of the various embodiments, variants and specific design features of the field of view display device and of the vehicle according to the above aspects of the invention mentioned above in the description and in the following claims can be used in the case of the FIGS 1 until 6th examples shown. They are therefore not all repeated again below. The same applies accordingly to the definitions of terms and effects already given above in relation to individual features that are included in the 1-6 are shown.

1 shows in a simplified schematic perspective side view an example of a spatially compact field of view display device 1 according to the above first aspect of the invention obliquely from above in operation and in a suitable position and orientation relative to a user 3 whose eye position is predetermined and, for example, each in the middle of an associated eyebox area Ea and Eb the field of view display device 1 lies. 2 until 5 show further views of the field of view display device 1 according to the 1 , each in their predetermined arrangement relative to the user 3 .

1 until 5 can on the one hand be understood as pure principle sketches of the optical arrangement of the type set out here, that is to say purely schematic and not true to scale, because deviating distance relationships can in principle also lead to the result described here. However, they can 1-5 can also be understood to be true to scale as an example of an arrangement that can be implemented well and is optimized as described herein. For this purpose, in particular the measurement scales drawn in below in these figures can be used.

As in 6th indicated schematically is the field of view display device 1 to a permanent integration in a higher-level system, such as B. a motor vehicle or aircraft or a building without mechanical connections to the user 3 and thus provided in a construction that is perceived as practically interference-free for this. As in the example according to the 6th illustrated, it can in particular for subsequent attachment to a headliner of a motor vehicle 14th be designed and for this purpose an in 6th schematically indicated foldable housing 2 of the type described herein, that in the rest 1-5 for a detailed illustration of the optical arrangement is omitted.

The field of view display device 1 includes a spatially compact projector system 4th which, as in the 1-6 shown for mounting above the predetermined user eye positions indicated by in an in 1 indicated eyebox level E. lying eyebox areas Ea (for the right eye) and Eb (for the left eye) are defined (cf. 3 ). As in 1 shown particularly clearly recognizable, there is the projector system 4th from two separate projector units 4a and 4b that are symmetrical about a central plane Y Z of the projector system 4th lying, where the in 1 drawn in "projector own" Cartesian coordinate system XYZ should not be confused with the usual vehicle coordinate system, on which it can be aligned in parallel during operation, but does not necessarily have to be. So can the so-called vertical center plane Y Z of the projector system 4th for example in a motor vehicle 14th the 6th be aligned approximately parallel to a plane spanned by the vertical and longitudinal axes of the vehicle of the usual vehicle coordinate system.

The projector unit on the left from the user's point of view 4a generates the image for his right eye in the associated eyebox area Ea while the projector unit on the right 4b the image for his left eye in the associated eyebox area Eb generated (cf. also 3 ). To simplify the illustration of the beam path, in 1 in both projector units 4a and 4b only one from a display center point of the respective image-generating display 10a respectively. 10b outgoing partial ray bundle indicated, while the corresponding full / whole projection light ray bundle La and Lb that from the display 10a respectively. 10b the respective projector unit 4a and 4b go out in operation, for example in 2 are indicated by means of several display points.

Furthermore, the field of view display device 1 a combiner disc 8th on, which is designed and in such an operating position below the two projector units 4a and 4b and at a predetermined horizontal distance D. (see 2 ) of about 280 mm in front of the eyebox areas in this example Ea and Eb fixed or fixable during operation is that of the projector units 4a and 4b two projection light beams generated during operation La and Lb on one to the user 3 facing reflective surface 9 the combiner disc 8th and thrown from this to his eyes to create one in his field of vision behind the combiner pane 8th superimposed virtual display image V (see. 6th ) are reflected.

This arrangement enables a significantly more compact design than, for example, conventional HUD projection optics that only use a single projector to generate images for the left and right eyes. On the one hand, in the present example, each projector unit generates 4a , 4b with the associated beam path only a sharply delimited eyebox area Ea , Eb around the respective eye. On the other hand, left / right mirror-symmetrical imaging errors of the reflection surface can occur in each of these two beam paths (also referred to herein as channels) 9 the combiner disc 8th be compensated separately by their own optics and their own pre-distortion of the display content. This makes it possible to use a high-magnification optics, which is the volume of the projector system 4th and the display size of the imaging displays 10a and 10b while the size of the generated virtual display image remains the same V reduced.

The individual optical elements of the field of view display device 1 the 1 until 6th and their function are discussed below with reference to 1 , 2 and 6th described in detail for this specific example.

Due to the arrangement of the two projector units 4a , 4b in the present example the result is an in 3 Position of the eyebox areas shown Ea and Eb for the left and right eyes in an eyebox plane perpendicular to the direction of beam propagation E. . For the specific interpretation as described in 1 and 2 can be seen, there is an elliptical eyebox with a size of 38mm x 25mm for each eye.

Both eyebox areas Ea and Eb are for example about 60mm separated from each other, which is a mean interpupillary distance AA for people equates.

So that the user can use these strongly delimited eyebox areas Ea and Eb does not leave in its movements, includes the field of view display device 1 in this example an eyebox tracking device 19th (in 1 only indicated schematically), which is designed and set up for this, a spatial position of the two eyebox areas Ea and Eb the current eye positions of both eyes of the user 3 to track. This can cause movements of the user 3 the location of the eyebox areas Ea and Eb automatically through suitable adjustments in the visor system, ie the field of view display device 1 , can be adjusted to the new eye position.

• - eine Methode für die Änderung der Lage der Eyeboxbereiche Ea und Eb in Bezug beispielsweise auf das Kraftfahrzeug 14 der 6; sowie
• - eine Methode für die Detektion der relativen Lage „Benutzeraugen zu Eyeboxbereichen“. Auf Basis dieser Größe kann über einen geeigneten Regelungsalgorithmus die Lage der Eyeboxbereiche Ea, Eb an die aktuellen Benutzeraugenpositionen angepasst werden.

Essential components of such a tracking are as described below:

• - a method for changing the location of the eyebox areas Ea and Eb in relation, for example, to the motor vehicle 14th the 6th ; as
• - a method for the detection of the relative position of "user eyes to eyebox areas". On the basis of this size, the position of the eyebox areas can be determined using a suitable control algorithm Ea , Eb can be adjusted to the current user eye positions.

By means of a suitable control unit 18th (see. 6th ) is the former method in the present case via the eyebox tracking device 19th and the second method via a detection device 20th , which are used to determine deviations of current user eye positions from the associated eyebox areas Ea / Eb is trained, implemented.

1. 1) Die gesamte Visoreinheit (Projektorsystem 4 + Visor/Combinerscheibe 8) wird verfahren und damit die Lage der Eyeboxbereiche Ea bzw. Eb an die Positionen der Benutzeraugen angepasst.
2. 2) Nur die Projektoreinheiten 4a bzw. 4b im Projektorsystem 4 werden bspw. in der XY-Ebene verschoben und evtl. auch verkippt. Die Position des Visors 8 bleibt unverändert. Auch dadurch wird eine Verschiebung der Eyeboxbereiche Ea und Eb in der Eyeboxebene E erreicht. Werden die Projektoreinheiten 4a und 4b unabhängig voneinander verfahren, so ergibt sich zusätzlich auch die Möglichkeit, eine Anpassung an unterschiedliche Augabstände oder auch an eine schiefe Kopfhaltung (Benutzeraugen in Y-Richtung versetzt) vorzunehmen.
3. 3) Der Visor 8 wird um seine Hoch- und Querachse verkippt (Rotation um Y- bzw. X-Achse).
4. 4) Eine Kombination der oben genannten Varianten 1)-3). So ist beispielsweise Variante 1) besonders nützlich für eine Nachführung über größere Distanzen, während Variante 2) einen besonders präzisen und schnellen Ausgleich kleiner Kopfbewegungen erlaubt. Eine Kombination würde eine Nachführung über einen größeren Bereich erlauben.

To change the position of the eyebox areas Ea and Eb : An adaptation of the eyebox areas Ea and Eb can be done in several ways or in different stages of expansion:

1. 1) The entire visor unit (projector system 4th + Visor / combiner disc 8th ) is moved and with it the position of the eyebox areas Ea respectively. Eb adapted to the positions of the user's eyes.
2. 2) The projector units only 4a respectively. 4b in the projector system 4th are shifted, for example, in the XY plane and possibly also tilted. The position of the visor 8th stays unchanged. This also causes a shift in the eyebox areas Ea and Eb in the eyebox level E. achieved. Become the projector units 4a and 4b proceed independently of one another, there is also the possibility of adapting to different interpupillary distances or to an inclined posture of the head (user eyes offset in the Y-direction).
3. 3) The visor 8th is tilted around its vertical and transverse axis (rotation around the Y or X axis).
4. 4) A combination of the above variants 1) -3). For example, variant 1) is particularly useful for tracking over larger distances, while variant 2) allows for a particularly precise and rapid compensation of small head movements. A combination would allow tracking over a larger area.

• Bei einer vergleichsweise einfachen ersten Variante, die in 4 veranschaulicht ist, der sogenannten „Camera only“-Variante, wird die relative Lage des Kopfes und der Augen des Benutzers in Bezug auf die Visoreinheit durch eine geeignete Sensorik mit einem oder mehreren Sensoren bestimmt. Aufgrund der vorbekannten, beispielsweise in der Detektionseinrichtung 20 oder der zugehörigen Steuerungseinheit 18 gespeicherten, Soll-Lage der Eyeboxbereiche Ea und Eb innerhalb des Visorsystems (Blickfeldanzeigevorrichtung 1) kann die relative Lage „Augen zu Eyeboxbereichen“ bestimmt werden und für die Nachführung verwendet werden. Als Sensoren können beispielsweise Kamerasysteme, Time-of-Flight-Sensoren, Structured-Light-Sensoren, LIDAR-, Ultraschall-Sensoren und dergleichen dienen.

The detection of the relative position “eyes to eyebox areas” can be done in the detection device 20th can also be implemented in several ways or in different stages of expansion:

• In the case of a comparatively simple first variant, which is shown in 4th is illustrated, the so-called “camera only” variant, the relative position of the head and the eyes of the user in relation to the visor unit is determined by a suitable sensor system with one or more sensors. Due to the previously known, for example in the detection device 20th or the associated control unit 18th saved target position of the eyebox areas Ea and Eb within the visor system (field of view display device 1 ) the relative position “eyes to eyebox areas” can be determined and used for tracking. For example, camera systems, time-of-flight sensors, structured light sensors, LIDAR, ultrasonic sensors and the like can serve as sensors.

4th shows in a side view of the field of view display device 1 according to the 2 schematically a possible arrangement of a camera system that acts as a sensor of the detection device 20th serves. This example is in the projector system 4th a camera 21 integrated into the spatial area of the user's face 3 and the eyebox areas Ea and Eb looks like through that from the camera 21 coverable field of view ( FOV , Field-of-View) indicated. Common image processing algorithms can be used in one of the camera 21 captured user image the position of his eyes, ie the two current user eye positions, can be determined. The detection device 20th is set up to convert the determined position of the user's eyes in pixels on the basis of the previously known geometry and position of the visor unit and / or a previous calibration into information about the (XY) position of the user's eyes in the eyebox plane E. to be converted with the saved target position of the eyebox areas Ea and Eb to be compared and to determine the above-mentioned deviation from this.

With this very simple method for the detection of possible deviations of the current positions of the user's eyes from the eyebox areas provided for this purpose Ea and Eb of the visor system, the spatial position of the eyebox areas in the visor system itself is not detected. Instead, a previously known target position or a calibrated position of the eyebox areas is used Ea and Eb regulated.

• 5 zeigt in einigen verschiedenen perspektivischen Ansichten ein Beispiel einer entsprechenden Anordnung von Markierungslichtquellen 22, in diesem Beispiel LEDs, im Projektorsystem 4. Rund um eine Linsenapertur (siehe weiter unten die ausführliche Beschreibung der Projektoroptik) am optischen Ausgang der Projektoreinheit 4b für das linke Auge sind mehrere, in diesem Beispiel vier LEDs, in einem etwa gleichen Abstand voneinander angeordnet: LED1, LED2, LED3 und LED4. Eine entsprechend symmetrische Anordnung für die zweite Projektoreinheit 4a für das rechte Auge ist vorgesehen und wurde in 5 aus Darstellungsgründen weggelassen. Wie weiter unten im Detail beschrieben, liegt in einer bevorzugten optischen Anordnung die genannte Apertur der Projektoreinheit 4b ungefähr in einem Abstand der doppelten Visor-Brennweite f der Combinerscheibe 8 entfernt. Die Eyeboxebene E liegt dabei ebenfalls im Abstand der doppelten Brennweite vom Visor entfernt. Damit liegt eine 2f-1:1-Abbildung vor, d. h. die LEDs werden durch den Visor in die Eyeboxebene E abgebildet. Die entsprechenden Fokusspots F1-F4 umranden den Eyeboxbereich Eb des linken Auges. Das durch die Anordnung der LEDs um die Linsenapertur vorgegebene Muster wird also in Eyeboxebene E projiziert. Als „Projektionsfläche“ P dient dabei das Gesicht des Benutzers.

Also about a possible shift in the position of the eyebox areas Ea and Eb that are caused, for example, by relatively small mechanical changes in the system such as B. a slight tilting of the Combiner disc 8th In a further development of the above detection method described below, a current / real position of the eyebox areas is also provided Ea and Eb detected for the determination of the specified deviation. The existing optical properties of the visor system are used to determine the relative position of the eyebox areas Ea / Eb to make it measurable to the user's eyes. The location of the eyebox areas Ea and Eb is achieved through the use of suitable marking light sources 22nd in the projector system 4th again for suitable sensors, such as. B. a camera system that is similar to the camera system 21 the 4th can be arranged, made visible:

• 5 shows an example of a corresponding arrangement of marking light sources in several different perspective views 22nd , in this example LEDs, in the projector system 4th . Around a lens aperture (see the detailed description of the projector optics below) at the optical output of the projector unit 4b For the left eye, several LEDs, in this example four LEDs, are arranged at approximately the same distance from one another: LED1, LED2, LED3 and LED4. A correspondingly symmetrical arrangement for the second projector unit 4a for the right eye is intended and was made in 5 omitted for reasons of illustration. As described in detail below, the said aperture of the projector unit is located in a preferred optical arrangement 4b approximately at a distance of twice the visor focal length f the combiner disc 8th removed. The eyebox level E. is also at a distance of twice the focal length from the visor. This results in a 2f-1: 1 image, ie the LEDs are brought into the eyebox level through the visor E. pictured. The corresponding focus spots F1-F4 border the eyebox area Eb of the left eye. The pattern given by the arrangement of the LEDs around the lens aperture is therefore in the eyebox plane E. projected. As a "projection surface" P. the face of the user is used.

A camera, such as in 4th sketched, the eyebox level E. are recorded. As described in the former detection method above, the position of the user's face and eyes can be seen in the camera image 3 can be detected by appropriate image processing. In addition, the position of the LED focus spots that make up the eyebox area should now be derived from the camera image Eb border, can be determined in the face of the user. The entire information about the relative position of the focus spots is then available from direct measurement, that is to say without fault-prone assumptions about a target position of the eybox F1-F4 showing the location of the eyebox area Eb result, in relation to the position of the eye positions, which can also be determined, on the basis of which the eyebox areas are tracked Ea and Eb can be done.

The advantage of this detection arrangement is that the same optical channel is used for projecting the LED pattern as for projecting the visor image and generating the eyebox areas. The position of the eyebox areas shifts Ea and Eb due to geometric / mechanical deviations in the beam path, such as tilting the visor or the deflection mirror 6th (see. 1 , 2 , 6th as described below), this change also affects the position of the LED focus spots in the same way. As a result, this method is extremely robust with regard to tolerances / deviations in the beam path of the field of view display device 1 .

The following are the individual optical elements of the field of view display device 1 the 1 until 6th and their function are described in detail.

The beam paths of the two projector units 4a and 4b cross each other in this example, as in 1 can be seen particularly well in front of the combiner pane 8th . Their reflection surface 9 can, as in 1 shown as a concave mirror for collimating towards the user 3 reflected projection light beam La and Lb be designed and arranged.

With the arrangement outlined in this example, a 35 ° x20 ° virtual display image, for example, can be created V at a projection distance of about 2.5 m in front of the user's eyes 3 using a projector system 4th with a volume of only about 2.5 L, which is, for example, the total volume of the foldable housing 2 the field of view display device 1 in its closed state (s. 6th and the associated description below). The resulting image size can in particular correspond to a 65-inch to 70-inch screen, such as, for example, a flat-screen TV, at a distance of 2.5 m with a comparable resolution.

Display: That in every projector unit 4a / 4b intended display 10a respectively. 10b to generate the associated projection light beam La / Lb The display content to be transported can be a small high-resolution display, such as is used for smartphones or AR / VR glasses. In the specifically shown arrangement, for example, a 3.5 "display with> 1000ppi can be used. In addition to other possible display technologies, LCD displays or micro-Led displays can particularly be used as the technology be suitable, since for a good readability of the virtual display image V a high luminance of the displays 10a / 10b is required. That on the display 10a / 10b The displayed image can in particular be pre-distorted in order to avoid any further optics of the field of view display device 1 to compensate for resulting image distortions.

Aspherical projector lenses: The one in every projector unit 4a / 4b intended optical imaging system 12a respectively. 12b includes in 1 and 2 two each, in 5 three projector lenses that make up the display of the display 10a respectively. 10b on a real intermediate image Z in the area of the focal point of the reflection surface 9 the projection screen 8th projected. The projector lenses can in particular have aspherical surfaces in order to achieve the highest possible image sharpness. The refractive power required for projection is divided between two or three projector lenses in order to improve the image quality.

Free-form mirror: in every projector unit 4a / 4b is in the beam path between the display 10a / 10b and the imaging optical system 12a / 12b a freeform mirror 13a / 13b intended. In this example, it has a curved concave surface, which is used to compensate for the aberrations that are later caused by the reflection on the reflection surface 9 the combiner disc 8th can arise, is trained. Alternatively, this function could also be implemented by a lens with free-form surfaces.

Deflecting mirror: One in the beam path of both projection light beams La and Lb between the projector system 4th and the projection screen 8th suitably arranged deflecting mirror 6th , which is designed as a plane mirror in this example, is used to deflect both projection light beams La and Lb from the one above the projection screen 8th arranged projector units 4a and 4b in the direction of the reflective surface 9 the combiner disc 8th . Without this deflection mirror 6th would be the spatially compact projector system 4th wander into the area just above the user's head.

Real intermediate images: As in particular in 1 can easily be seen from the display 10a / 10b outgoing projection light beam La and Lb through the projector optics in front of the reflection surface 9 the combiner disc 8th focused. In this example, a real intermediate image is created there Z , the shape and aberrations of which can be such that the image in the next step through the reflection surface 9 the combiner disc 8th Compensate for errors that arise. In the present example, the image of the left and right channels are virtually superimposed at this point.

Visor, ie combiner disc: The reflective surface that acts as a visor 9 the combiner disc 8th in this example is a concave curved (generally partially transparent) mirror (concave mirror). The real intermediate images, which are close to its focal point, are created by the visor Z of the left and right channels into a virtual image V pictured behind the visor. A parabolic shape of this concave mirror can in particular be advantageous. The base radius of the parabolic reflective surface 9 , ie their double focal length 2f, is in the present embodiment, for reasons explained below, as the horizontal distance D. the reflective surface 9 to the eyebox areas intended for the user's eyes Ea and Eb chosen.

• Abstand Visor zu Eyeboxebene: Dieser Abstand kann als Startpunkt der Überlegungen gewählt werden. Der horizontale Abstand D der Combinerscheibe 8 zu den Augen des Benutzers ergibt sich im vorliegenden Beispiel als ein Kompromiss aus optischen, ergonomischen und Fahrzeugintegrations-Aspekten. Ist die Combinerscheibe 8 nahe an den Augen, wird die benötigte Combinerscheibenfläche kleiner. Allerdings können sich gegebenenfalls Probleme im Falle eines Crashs ergeben, der Benutzer 3 fühlt sich tendenziell beengt durch die Combinerscheibe 8, und die Faltung des optischen Strahlengangs ist schwieriger um den Kopf des Benutzers 3 herumzuführen. Große Abstände bedingen hingegen eine größere Combinerscheibenfläche, die wiederum beispielsweise schwerer ins Fahrzeug zu integrieren sein kann. Durch Versuche wurde vorliegend ein horizontaler Abstand D von 280 mm als besonders geeignet festgelegt.

For a correct function and an arrangement of the projector optics that is as compact as possible, the ratios of geometric distances explained below in relation to the radius of the reflection surface designed as a concave mirror can be used in particular 9 the combiner disc 8th be particularly suitable or inexpensive. Specifically for the in 2 The optical arrangement shown, these dependencies are as follows:

• Distance visor to eyebox plane: This distance can be chosen as the starting point for the considerations. The horizontal distance D. the combiner disc 8th to the eyes of the user results in the present example as a compromise between optical, ergonomic and vehicle integration aspects. Is the combiner disc 8th close to the eyes, the required combiner pane area becomes smaller. However, problems may arise in the event of a crash for the user 3 tends to feel cramped by the combiner pane 8th , and the folding of the optical path is more difficult around the user's head 3 show around. Large distances, on the other hand, require a larger combiner pane area, which in turn can be more difficult to integrate into the vehicle, for example. A horizontal distance has been established in the present case through tests D. of 280 mm defined as particularly suitable.

Visor radius: The radius R (or focal length f = R / 2) of the reflective surface designed as a spherical or parabolic concave mirror 9 the combiner disc 8th became equal to the horizontal distance specified above for reasons explained below in this example D. the combiner disc 8th to the eyebox areas Ea / Eb set. The present case is therefore for the concave reflection surface 9 a focal length f = 140 mm (or visor radius R = 280mm) was chosen.

Location of the real intermediate image: the reflection surface 9 is optically a concave mirror. To the desired virtual display image V to produce, need the projector units 4a and 4b each a real intermediate image Z produce that at a distance less than or equal to the focal length f of the concave mirror lies in front of this. In the specific design, f = 140mm.

Optimal location of the projector units: The requirement for a projector system that is as compact as possible 4th a particularly suitable location / position of the last projector lens (its aperture here also as the optical output of the projector unit) can be realized 4a / 4b is called) as follows. As a rule of thumb for the relative distances in the field of view display device 1 of the type set out herein may apply: $$\begin{array}{l}\left(\text{Distance projector system}-\text{Visor}\right)=\left(\text{Distance visor}-\text{Eyebox level}\right)\\ =\text{Radius visor}.\end{array}$$

In this case, the distances mentioned correspond to twice the focal length 2f of the reflection surface 9 the combiner disc 8th , so there is the condition for a 2f or 1: 1 mapping. One can imagine that the aperture of the final projector lens is at the exit of the respective projector unit 4a / 4b into the eyebox area through the reflective surface 9 is mapped. It turns out that if this condition is fulfilled, all the rays that are required to generate the desired eyebox area are superimposed at the location of the last projector lens, so that the beam has a minimal cross section. This is the ideal position to create a specified eyebox area with the smallest possible group of projector lenses.

6th shows a greatly simplified schematic representation of a motor vehicle 14th with one in the passenger compartment 15th arranged compact field of view display device 1 of the type set forth herein, their projector system 4th in a foldable case 2 is housed. The field of view display device 1 can in particular according to 1 until 5 be trained. Their representation in 6th is not to be understood as being true to scale, but rather as being schematic.

The combiner disc 8th in a closed state of the foldable housing 2 with its entire surface on its bottom side 7th apply or form part of it and in its in 6th shown open state from the bottom 7th be hinged to a predetermined angle of incidence, that of the operating position of the combiner disk 8th is equivalent to. Furthermore, the foldable housing 2 one at a predetermined mirror spacing d from the projector system 4th in the beam path of the two projection light beams La and Lb extendable mirror wall 5 with one of the projector system 4th facing deflection mirror 6th on. The two projection light beams La and Lb are through the deflection mirror 6th in which by the predetermined mirror spacing d defined operating position according to 6th onto the above-mentioned reflective surface 9 the combiner disc 8th directed to the virtual display image V to generate behind it.

In his in 6th The closed state, not shown, is the foldable housing 2 spatially compact and can, for example, with an embodiment of the optical system according to FIG 1 until 5 have a volume of about 2.5 L, with the hinged combiner disc 8th with their reflective surface 9 on the bottom side 7th and the retractable mirror wall 5 with the deflection mirror 6th up to close to or close to the front projector lenses of the projector units 4a and 4b has retracted. In this way, the entire optical components of the field of view display device 1 when not in use, especially completely in the housing 2 hidden, covered and mechanically protected from the outside.

As in 6th The passenger compartment is indicated schematically purely by way of example 15th of the motor vehicle 14th upwards at least partially from one of the passenger compartment 15th facing headliner 16 limited. The case 2 the field of view display device 1 is with its roof side 11 the headliner 16 facing and on this by suitable fastening means 17th , in particular subsequently and permanently or also removable and / or displaceable, attached. Furthermore, in the motor vehicle 14th for example a control unit mentioned herein 18th be provided for the electrical control of the field of view display device 1 to extend the mirror wall 5 and / or to open the projection screen 8th and in particular also to carry out the functionality of the eyebox tracking device described herein 19th and the detection device 20th is trained.

List of reference symbols

1

compact field of view display device

2

foldable housing

3rd

user

4th

Projector system

4a, 4b

Right / left eye projector unit

5

extendable mirror wall

6th

Deflection mirror

7th

Bottom side

8th

Combiner disc

9

Reflective surface

10a, 10b

imaging display

11

Roof side

12a, 12b

optical imaging system with projector lens (s)

13a, 13b

Freeform mirror

14th

Motor vehicle

15th

Passenger compartment

16

Headliner

17th

Fasteners

18th

Control unit

19th

Eyebox tracking facility

20th

Detection device

21

camera

22nd

Marker light sources

V

virtual display image

E.

Eyebox level

Ea, Eb

Eyebox areas for the right or left eye of the user

Z

real intermediate image

La, Lb

Projection light beam for the right / left eye

D.

horizontal distance

d

predetermined mirror spacing

f

Focal length of the concave reflection surface

XYZ

Projector-specific or visor-bound Cartesian coordinate system

Y Z

Center level of the projector system

FOV

Field-of-view of the camera

F1-F4

Focus spots of the marker sources

P.

“Projection surface” for focus spots of the marking sources on the user's face

AA

Distance of the eyebox areas from each other or mean eye distance

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was 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.

Patent literature cited

• DE 102017208028 A1 [0004]
• DE 102017214627 A1 [0005]

Claims (10)

Compact field of view display device (1) which is designed to be fixed in place in a higher-level system, in particular on a headliner (16) of a motor vehicle (14), comprising: - A spatially compact projector system (4) with two projector units (4a, 4b), which are arranged symmetrically about a vertical center plane (YZ) of the projector system (4) and each for generating a projection light beam (La, Lb) with a intended only for a user eye Display contents are formed; - A combiner pane (8) which is designed in this way and can be fixed or fixable in an operating position defined with respect to the projector system (4) below it at a predetermined horizontal distance (D) in front of two two-dimensional eyebox areas (Ea, Eb) intended for only one user eye is that each of the two projection light beams (La, Lb) is reflected by the combiner pane (8) to the associated eyebox area (Ea, Eb), so that a virtual display image (V) into the field of vision of the user (3) behind the combiner pane (8) is displayed; as - A detection device (20) which is designed to determine deviations of current user eye positions from the associated eyebox areas (Ea, Eb). Field of view display device (1) according to Claim 1 which further comprises an eyebox tracking device (19) which is designed and set up to track a spatial position of the two eyebox areas (Ea, Eb) to the respective current user eye positions as a function of the determined deviations by - an entire visor unit, which comprises the projector system (4) and the combiner pane (8), is moved in one, two or all three spatial dimensions in the higher-level system; and / or - the projector units (4a, 4b) are moved together and / or relative to one another in the projector system (4); and / or - the combiner disk (8) is moved relative to the projector system (4). Field of view display device (1) according to Claim 1 or 2 - the detection device (20) of which has one or more sensors for detecting a spatial area containing the eyebox areas (Ea, Eb) and is designed to determine current user eye positions from a user image recorded by these sensors, with preferably at least one of these sensors in the visor unit, which comprises the projector system (4) and the combiner pane (8) is integrated. Field of view display device (1) according to Claim 3 , which further - has one or more marking light sources (22), in particular LEDs (LED1, LED2, LED3, LED4), which are designed and arranged in the projector units (4a, 4b) in such a way that their marking light beam bundles through the optics of the Visor unit into which eyebox areas (Ea, Eb), preferably in their respective edge area, are directed, in particular focused, to mark the eyebox areas (Ea, Eb) in the user image captured by the sensors; and - the detection device (20) is additionally designed to determine a current position of the two eyebox areas on the basis of this marking and to use the result in determining the deviations of the user's eye positions from the eyebox areas (Ea, Eb). Field of view display device (1) according to Claim 4 wherein one or more of the marking light sources (22) are infrared light sources and one or more of the sensors are infrared light sensors. Field of view display device (1) according to Claim 4 or 5 - A user-side reflection surface (9) of the combiner disk (8) in its operating position represents a concave mirror symmetrical about the vertical center plane (YZ), in particular a parabolic, which is designed and arranged for at least partially collimating both projection light beams (La, Lb) wherein the combiner pane (8) is in particular at least partially transparent to the ambient light incident on the rear; - In the operating position of the combiner disk (8), the optical path length of the respective projection light beam (La, Lb) between an optical output of the associated projector unit (4a, 4b) and the concave mirror and / or between the concave mirror and the associated eyebox area (Ea, Eb) each is approximately twice the focal length (f) of the concave mirror; - The marking light sources (22) being arranged at the optical output of the respective projector unit (4a, 4b) in such a way that they are imaged by the optics of the visor unit in an edge area of the associated eyebox area (Ea, Eb) for its marking. Field of view display device (1) according to Claim 6 in which - the marking light sources (22) are permanently connected to the projector system or to the respective projector unit (4a, 4b); and / or - the marking light sources (22) are arranged around a lens aperture at the optical output of the respective projector unit (4a, 4b) so that they are imaged by the optics of the visor unit in an edge area of the associated eyebox area (Ea, Eb) for marking it . Field of view display device (1) according to one of the preceding claims, in which each projector unit (4a, 4b) has a display (10a, 10b) for generating the display content to be transported by the associated projection light beam (La, Lb) and an optical imaging system (12a, 12b) , which is designed to map this display content into a real intermediate image (Z) that is generated in the beam path of the projection light beam (La, Lb) between the projector system (4) and the combiner disk (8) in their operating position. The field of view display device (1) according to one of the preceding claims, further comprising: - A foldable housing (2) in which the projector system (4) is accommodated, the housing (2) being spatially compact in its closed state and surrounding the projector system (4) in particular from all sides, wherein - In the closed state of the housing (2) the combiner disc (8) rests with its entire surface on its bottom side (7) or forms part of it and can be opened from the bottom side (7) to a predetermined angle of incidence that corresponds to the operating position of the combiner disc ( 8) corresponds, and / or - The housing (2) has a mirror wall (5) which can be extended to a predetermined mirror distance (d) from the projector system (4) in the beam path of the two projection light beams (La, Lb) and has a deflecting mirror (6) facing the projector system (4), wherein the two projection light beams (La, Lb) are directed by the deflecting mirror (6) in its operating position defined by the predetermined mirror spacing (d) onto a reflecting surface (9) of the combiner pane (8) in order to generate the said virtual display image (V) behind it . Vehicle, in particular a motor vehicle (14), comprising: - a passenger compartment (15) which is at least partially delimited at the top by a headliner (16) facing the passenger compartment (15); and - a field of view display device (1) according to one of the preceding claims, in particular according to Claim 9 which is attached to the headliner (16), in particular to a roof side (11) of the foldable housing (2) facing away from the bottom side (7).

Images