WO2015158830A1

WO2015158830A1 - Display device and display method

Info

Publication number: WO2015158830A1
Application number: PCT/EP2015/058275
Authority: WO
Inventors: Ersun Kartal
Original assignee: Carl Zeiss Smart Optics Gmbh
Priority date: 2014-04-17
Filing date: 2015-04-16
Publication date: 2015-10-22
Also published as: DE102014207493A1

Abstract

The invention relates to a display device comprising a retaining device (2) which can be placed on the head of a user (B) and an imaging module (20) which is secured to the retaining device (2) and has an imaging unit (5) that generates an image and has an optical imaging system (6), said optical imaging system imaging the generated image when the retaining device (2) is placed on the head such that the user (B) can perceive the generated image as a virtual image. The display device also comprises a control unit (9) for controlling the imaging module (20). A measuring module (19) is provided which measures a position of the head of the user (B) and/or a parameter which characterizes a property of the surroundings when the retaining device (2) is placed on the head. The measuring module generates a data set based on the position and/or the parameter and forwards the data set to the control unit (9), which controls the imaging module (20) dependent on the data set such that the virtual image is imaged on one of at least two different image planes (B1, B2) of the imaging module (20).

Description

Display device and display method

The present invention relates to a display device having a holding device to be placed on the head of a user, an image module attached to the holding device, an image unit forming an image, and imaging optics to image the formed image in the head-mounted state of the holding device in that the user can perceive it as a virtual image, and a control unit for controlling the image module. Furthermore, the present invention relates to a corresponding display method for such a display device of the type mentioned.

Such display devices are typically designed such that the virtual image is presented to the user in a predetermined image plane having a predetermined distance from the imaging optics. This leads to difficulties in the use of such a display device in practice, since a user, when he moves outdoors, usually accommodated with his eyes to infinite. If he is in a closed room, the user will usually accommodate a shorter distance, for example in the range of 1 m to 3 m. Now, if the position of the image plane does not match, the user must, if he wants to perceive the virtual image, Accommodate on the image plane, which is perceived as disadvantageous. In particular, then the virtual image often no longer matches the perception of the environment, which gives the user a worse image impression.

Proceeding from this, it is therefore an object of the invention to provide a display device of the type mentioned in such a way that the difficulties described can be almost completely overcome. Furthermore, the corresponding display method should also be developed in the same way.

The object is achieved in a display device of the type mentioned above in that a measuring module is provided which measures the position of the head of the user and / or characterizing a property of the environment parameters in the mounted on the head state of the holding device, generates a data set and forwards it to the control unit, which controls the image module as a function of the data record in such a way that the virtual image is imaged in one of at least two different image planes of the image module. This advantageously ensures that the position of the image plane is adapted to the current environmental condition or the position of the head of the user. The virtual image representation therefore fits in better for the user in his actual environment, a strong refocusing is no longer necessary, so that overall there is an improved visual impression for the user.

The measuring module can be connected to the holding device (mechanically). In particular, it may be attached to the holding device.

However, it is also possible that the measuring module is not attached to the holding device and thus not mechanically connected to the holding device. The measuring module can thus be provided as a separate module. It can e.g. be realized by a mobile phone, e.g. Measures location data as a parameter characterizing a property of the environment. This may be e.g. whether the user carrying the mobile phone is in a room or outdoors.

The transmission of the data set to the control unit can be wireless. For this purpose, known radio protocols can be used. For example, a so-called Bluetooth connection can be used. However, it is also possible that the transmission of the data record takes place via a connecting line.

The measuring module may have a distance sensor. The distance sensor can work in particular according to the transit time method. In the transit time method, a light pulse is emitted and the time is measured until the reflection of the light pulse arrives again at the distance sensor. The time required is proportional to the distance.

However, any other type of distance sensor can be used. Furthermore, the measuring module can have a camera. On the one hand, a distance measurement can be carried out with this camera. On the other hand, a camera image can also be evaluated and the desired data record can be generated on the basis of this evaluation. In particular, a context-sensitive evaluation can be carried out automatically. Furthermore, the measuring module may comprise a position sensor. Such position sensors are known to the person skilled in the art and can be designed, for example, as a gyroscope. Thus, the position sensor can measure the tilt angle of the holding device and thus of the head about one, two or also all three axes (for example x, y and z axis). The at least two different image planes differ, in particular, in their distance from the imaging optics. Thus, a first of the image planes may be spaced from the imaging optics in the range of 0.5 m to 5 m. A second image plane of the image planes may, for example, have a distance of greater than 5 m, greater than 10 m, greater than 20 m, greater than 30 m. In particular, the second image plane can also lie at infinity.

Of course, the image module may have more than two different image planes. In particular, it may have three, four, five, six, seven, eight, nine, ten or more image planes, which differ in particular in their distance from the imaging optics.

The imaging optics may comprise a spectacle lens having a coupling-in section in an edge region of the spectacle lens and a decoupling section in a middle region of the spectacle lens, the spectacle lens comprising a light-guiding channel, the light bundle of pixels of the generated image which are coupled into the spectacle lens via the coupling-in sections of the spectacle lens, in the spectacle lens leads to the coupling-out section in order to decouple it from the spectacle lens via the decoupling section.

The light guide may e.g. take place by total internal reflection at the front and back of the lens. However, it is also possible to provide the corresponding sections of the front and back of the spectacle lens with a reflective or partially reflective coating. Furthermore, for example, a reflective layer which replaces the reflection at the front or rear side can be arranged in the spectacle lens. It is also possible to arrange two spaced apart reflective layers in the spectacle lens, which then cause the light guidance from the coupling-in section to the decoupling section in the spectacle lens.

The decoupling portion may have a plurality of spaced-apart deflection surfaces, which are in particular formed as reflective or partially reflective deflection surfaces. The reflective or partially reflective deflection surfaces can also be referred to as Fresnel surfaces.

The reflective or partially reflective deflection surfaces can cause a pure beam deflection. However, it is also possible to design the reflective or partially reflective deflection surfaces such that they also have an imaging effect in addition to the pure beam deflection. This imaging effect can for example be used to correct at least one aberration. The reflective or partially reflective deflection surfaces are preferably each formed as a planar surface. However, it is also possible that the reflective or partially reflective deflection surfaces themselves are each curved. The display device according to the invention may have further, known in the art elements that are necessary for their operation.

There is further provided a display method for a display device having a holding device mounted on the head of a user and an image module attached to the holding device, the image unit forming an image, and imaging optics displaying the formed image in the upside down state of the holding device such that the user can perceive it as a virtual image, wherein the position of the head of the user and / or a parameter characterizing a property of the environment is measured in the head-mounted state of the holding device, and a data record is generated therefrom depending on the data set, the image module is driven such that the virtual image is imaged in one of at least two different image planes of the image module.

This makes it possible to adapt the image projection or the generation of the virtual image to the current environment of the user.

The display method according to the invention can have the method steps described in connection with the display device according to the invention (including its developments).

In the same way, the display device according to the invention may comprise elements which are necessary for the operation of the display device according to the invention (including its developments) or are described in this connection. It is understood that the features mentioned above and those yet to be explained below can be used not only in the specified combinations but also in other combinations or alone, without departing from the scope of the present invention. The invention will be explained in more detail for example with reference to the accompanying drawings, which also disclose characteristics essential to the invention. Show it: Fig. 1 is a schematic perspective view of an embodiment of the display device according to the invention;

Fig. 2 is an enlarged partial sectional view of the first spectacle lens 3;

Fig. 3 is a schematic representation for explaining a first image plane E1, and

Fig. 4 is a schematic representation of FIG. 3 for explaining the position of a second image plane E2.

In the embodiment shown in FIG. 1, the display device 1 according to the invention comprises a holding device 2 which can be placed on the head of the user and which is designed as a conventional spectacle frame in the embodiment described here, and a first and a second spectacle lens 3, 4 attached to the holding device 2 are attached. The holding device 2 with the spectacle lenses 3 and 4 may e.g. be designed as sports glasses, sunglasses and / or glasses for the correction of ametropia, wherein the user on the first spectacle lens 3, a virtual image can be played in his field of vision, as described below. As best seen in the enlarged fragmentary sectional view in Fig. 2, the display device 1 comprises an imaging unit 5 (eg comprising an OLED module) capable of forming an image which is mirrored into the user's field of view as the virtual image shall be. For this purpose, the display device 1 has an imaging optical unit 6, which contains an optical element 7 arranged between the image unit 5 and the first spectacle lens 3. Furthermore, the first spectacle lens 3 itself also serves as part of the imaging optics 6.

The imaging unit 5 is designed as a planar imager with a plurality of e.g. formed in columns and rows arranged pixels, wherein from each pixel, a light beam 8 can go out. By appropriate control of the pixels by means of a control unit 9, the desired image can be generated. In Fig. 2 is representative of the light beam 8 of the beam path of a light beam located, so that also below the light beam 8 is the speech.

The emanating from the image unit 5 light beam 8 passes through the optical element 7 and enters via an end face 10 of the first spectacle lens 3 in the first spectacle lens 3 and is then in the first spectacle lens 3 by total internal reflection at the front and back 1 1, 12 of the first Spectacle lens 3 is guided to a decoupling section 13. The decoupling section 13 has a plurality of adjacently arranged reflective deflection surfaces 14 or reflective facets 14 on, which deflect the light beam 8 in the direction of the rear side 12, that it emerges from the spectacle lens 3 via the rear side 12.

Thus, a user who carries the display device 1 according to the present invention as intended can perceive the image generated by the image unit 5 as a virtual image when looking at the extraction section 13. In the embodiment described here, the user must look slightly to the right with respect to the viewing direction G of a straight-ahead view. In Fig. 2 is for clarity, the fulcrum 15 of the user's eye and in the Eyebox 1 6 (the area which is provided by the display device 1 and in which the eye of the user can move and he always still the generated image as a virtual Picture can be seen).

The section of the first spectacle lens 3, via which the light beam 9 is coupled into the spectacle lens 3, can also be referred to as the coupling-in section 17. The corresponding sections of the front and back 1 1, 12 of the lens 3 between the coupling portion 17 and the Auskoppelabschnitt 13, where the total internal reflection takes place, thus serve as a light guide channel 18, which is coupled via the coupling section 17 light beams 9 to the coupling-out section 13th leads. The display device according to the invention further comprises a measuring module 19, which is shown schematically in Fig. 1 and in Fig. 2. By means of the measuring module 19, for example, the head position of the user wearing the display device on his head can be measured and output as a data set to the control unit 9. Additionally or alternatively, at least one parameter characterizing a property of the environment can be measured by means of the measuring module 19. For example, the measuring module may include a distance sensor that measures the distance to objects present in a certain range in the viewing direction in front of the user. The measurement results are in turn added as a record of the control unit. The control unit 9 controls the image unit 5 and / or the imaging optics 6, which together can also be referred to as the image module 20, such that the generated image is imaged as a virtual image in one of at least two image planes of the image module 20 located differently from the user , In Fig. 3, a first image plane E1 is shown with respect to a user B shown very schematically. The first image plane E1 has a first distance d1 from the head of the user B or from the user's eye. In Fig. 3, the display device 1 is shown only schematically for simplicity of illustration. At this distance d1, the generated virtual image is sharply perceived by the user. The size for the distance d1 may be, for example, in the range of 50 cm to 5 m. In Fig. 4, the position of a second image plane E2 is shown in the same manner as in Fig. 3, wherein the distance to the head of the user B or the eye of the user B is now d2, where d2 is greater than d1. For example, the value of d2 may be greater than 3 meters, greater than 5 meters, and most preferably greater than 10 meters. In particular, the image plane E2 can also lie at infinity.

With the display device 1 according to the invention, it is thus possible to automatically adapt the representation of the virtual image to the current requirements for the user. Thus, the representation in the first image plane E1 can be selected when the user is in a room or when the user is looking at the floor. The representation in the second image plane E2 can be selected when the user B moves outdoors and / or looks straight ahead. To effect the display in the first or second image plane E1, E2, e.g. the image unit 5 are moved so that their distance from the optical element 7 and / or the first spectacle lens 3 is changed, as indicated by the double arrow P1.

Additionally or alternatively, the optical element 7 can be moved as indicated by the double arrow P2. Thus, a change in distance between the optical element 7 and the spectacle lens 3 and / or between the optical element 7 and the image unit 5 is possible.

For moving the image unit 5 and / or the optical element 7, a suitable actuator or actuators can be provided. The actuator may e.g. be a piezo actuator.

The measuring module 19 may comprise a camera, which receives an area in front of the display device 1. With a suitable image recognition (by software and / or hardware), the desired data record can be generated, which is forwarded to the control unit 9. In particular, the camera can be designed as a 3D camera that takes a three-dimensional image.

In the described embodiment, the coupling of the light beam 8 on the end face 1 0 of the first spectacle lens 3 takes place. Of course, it is also possible, the display device 1 in such a way that the coupling takes place on the back 12 of the first spectacle lens 3.

The first spectacle lens 3 preferably has a curved front side 1 1 and / or a curved rear side 12. The optical element 7, the image unit 5 and the control unit 9 can be arranged in the right eyeglass temple of the spectacle-like holding device 2. In the previously described embodiments of the display device 1 according to the invention, the reflection of the virtual image into the field of view of the user B is effected by the first spectacle lens 3. Of course, an input reflection by the second spectacle lens 4 is also possible. Furthermore, the display device 1 can be designed such that information or virtual images are mirrored in via both spectacle lenses 3, 4. The reflection can be done so that a three-dimensional image impression is created. However, this is not mandatory.

The spectacle lenses 3, 4 may have a refractive power of zero or a non-zero refractive power, in particular for the correction of refractive errors. As shown in the figures, both the front side 1 1 and the back 12 of the spectacle lens 3 are curved. The front side 1 1 may in particular be spherically curved. If the spectacle lens has a non-zero refractive power to correct for ametropia, the curvature of the backside 12 is usually selected to achieve the desired correction.

The holding device 2 does not have to be designed as a spectacle-like holding device. It is also possible any other type of holding device with which a placement or carrying the display device 1 can be done on the head of the user. The features of the described embodiments can, as far as technically feasible, be combined with each other to provide further embodiments of the display device according to the invention.

Claims

claims

1 . Display device with

a holding device (2) which can be placed on the head of a user (B),

an image module (20) attached to the holding device (2) which images an image unit (5) which forms an image, and imaging optics (6) which image the image produced in the upside down state of the holding device (2), that the user (B) can perceive it as a virtual image, and

a control unit (9) for controlling the image module (20),

characterized by a measuring module (19) which measures the position of the head of the user (B) and / or a parameter characterizing a property of the environment in the mounted state of the holding device (2), generates a data record therefrom and sends it to the control unit (9) which, depending on the data set, controls the image module (20) in such a way that the virtual image is imaged in one of at least two different image planes (B1, B2) of the image module (20).

2. Display device according to claim 1, characterized in that the measuring module (19) comprises a distance sensor.

3. Display device according to claim 1 or 2, characterized in that the measuring module (19) comprises a camera.

4. Display device according to one of the above claims, characterized in that the measuring module (19) has a position sensor.

5. Display device according to one of the above claims, characterized in that the distance of the at least two different image planes (B1, B2) from the imaging optics (6) is different.

6. Display device according to claim 5, characterized in that the distance of one of the image planes (B1) in the range of 0.5 m to 5 m and the distance of another of the image planes (B2) is greater than 5 m.

7. Display device according to one of the above claims, characterized in that the measuring module (19) with the holding device (2) is connected.

8. Display device according to one of the above claims, characterized in that the imaging optics a spectacle lens (3, 4) with a coupling-in section (17) in one

Has edge region of the spectacle lens (3, 4) and a decoupling section (13) in a central region of the spectacle lens (3, 4),

wherein the spectacle lens comprises a light guide channel (18), the light bundles (8) of pixels of the generated image, which are coupled via the coupling portion (17) of the spectacle lens (3, 4) in the spectacle lens (3, 4) in the spectacle lens to the Decoupling section (13) leads to decouple them via the coupling-out section (13) from the spectacle lens (3, 4).

9. display method for a display device with

a on the head of a user (B) attachable holding device (2) and

an image module (20) attached to the holding device (2) which images an image unit (5) which forms an image, and imaging optics (6) which image the image produced in the upside down state of the holding device (2), that the user (B) can perceive it as a virtual image,

characterized in that in the mounted on the head state of the holding device (2) the position of the head of the user (B) and / or a characteristic of the environment characterizing parameter is measured, from a data set generated and depending on the data set, the image module (20 ) is controlled such that the virtual image is imaged in one of at least two different image planes (B1, B2) of the image module (20).