CN107167921B

CN107167921B - Display device

Info

Publication number: CN107167921B
Application number: CN201710586187.1A
Authority: CN
Inventors: 马新利
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2017-07-18
Filing date: 2017-07-18
Publication date: 2020-01-21
Anticipated expiration: 2037-07-18
Also published as: CN107167921A

Abstract

The disclosure provides a display, and relates to the technical field of augmented reality. The display includes: an objective lens unit for receiving a real image of an external scene; a microdisplay for generating a virtual image; a beam splitter for receiving and combining the real image and the virtual image to produce a combined image; the first polarizer is arranged between the objective lens unit and the beam splitter and used for controlling the light rays of the real image to be in a first polarization state before entering the beam splitter; the second polarizer is arranged between the micro display and the beam splitter and used for controlling the light of the virtual image to be in a second polarization state before entering the beam splitter; the third polarizer is arranged on an emergent light path of the beam splitter, comprises a first polarizing area and a second polarizing area, and is used for controlling light rays with different polarization states emitted from the beam splitter to respectively correspond to the first polarizing area and the second polarizing area for emission. The method and the device can enable the virtual image to shield the real image, thereby improving the image fusion effect.

Description

Display device

Technical Field

The present disclosure relates to augmented reality technologies, and in particular, to a display.

Background

AR (Augmented Reality) technology can apply virtual information to the real world so that virtual objects and real environments can be superimposed in real time on the same screen or in the same space while existing. Currently, AR technology has been applied to a variety of fields such as medical and military training, engineering design and prototyping, remote operation and remote presentation, and personal entertainment systems.

Taking the example of a see-through head-mounted display based on AR technology, it is possible to combine the virtual image produced by the display with the real image of the real scene, the desired effect of which is shown in fig. 1, i.e. the virtual car 101 can occlude the real physical platform 102 behind it, thus providing a truly coordinated fusion effect. However, in the prior art, the fusion effect actually generated by the see-through head-mounted display is as shown in fig. 2, that is, the virtual car 101 does not block the real physical scene behind it, which not only affects the display effect of the virtual image, but also affects the fusion effect of the virtual image into the real physical scene.

It is to be noted that the information disclosed in the above background section is only for enhancement of understanding of the background of the present disclosure, and thus may include information that does not constitute prior art known to those of ordinary skill in the art.

Disclosure of Invention

An object of the present disclosure is to provide a display device, thereby overcoming, at least to some extent, one or more of the problems due to the limitations and disadvantages of the related art.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows, or in part will be obvious from the description, or may be learned by practice of the disclosure.

According to an aspect of the present disclosure, there is provided a display including:

an objective lens unit for receiving a real image of an external scene;

a microdisplay for generating a virtual image;

a beam splitter for receiving the real image and the virtual image and combining the real image and the virtual image to produce a combined image;

the first polarizer is arranged between the objective lens unit and the beam splitter and used for controlling the light rays of the real image to be in a first polarization state before entering the beam splitter;

the second polarizer is arranged between the micro display and the beam splitter and used for controlling the light rays of the virtual image to be in a second polarization state before entering the beam splitter; and the number of the first and second groups,

the third polarizer is arranged on an emergent light path of the beam splitter and comprises a first polarizing area and a second polarizing area which are used for controlling light rays with different polarization states emitted from the beam splitter to respectively correspond to the first polarizing area and the second polarizing area for emission.

In an exemplary embodiment of the present disclosure, the first polarization region is located at a center of the third polarizer, and the second polarization region is located at an edge of the third polarizer;

the first polarizing area is used for controlling light of the virtual image to pass through and light of the real image to be cut off, and the second polarizing area is used for controlling light of the real image to pass through and light of the virtual image to be cut off.

In an exemplary embodiment of the disclosure, the light of the virtual image generated by the microdisplay is collimated light, and the first polarized light region is in accordance with a size of a virtual image presented by the microdisplay.

In an exemplary embodiment of the present disclosure, a distance from an imaging position of the real image of the external scene after passing through the objective lens unit to the beam splitter is equal to a distance from the microdisplay to the beam splitter.

In an exemplary embodiment of the present disclosure, the first polarizer is a first linear polarizer, the second polarizer is a second linear polarizer, and the third polarizer is a third linear polarizer;

the transmission axes of the first polarized light region and the second polarized light region of the third line polarized light sheet are perpendicular to each other, the transmission axis of the first line polarized light sheet is parallel to the transmission axis of the second polarized light region of the third line polarized light sheet, and the transmission axis of the second line polarized light sheet is parallel to the transmission axis of the first polarized light region of the third line polarized light sheet.

In an exemplary embodiment of the present disclosure, the light of the real image is in the first polarization state after exiting from the beam splitter, and the light of the virtual image is in the second polarization state after exiting from the beam splitter.

In one exemplary embodiment of the present disclosure, the first polarizer includes a first linear polarizer and a λ/4 wavelength phase retarder, the second polarizer includes a second linear polarizer and a λ/4 wavelength phase retarder, and the third polarizer includes a third linear polarizer and a λ/4 wavelength phase retarder;

the transmission axes of the first polarizing area and the second polarizing area of the third linear polarizer are the same and respectively form a pi/4 included angle and a 3 pi/4 included angle with the optical axis of the lambda/4 wavelength phase retarder, and the transmission axis of the first linear polarizer and the optical axis of the lambda/4 wavelength phase retarder and the transmission axis of the second linear polarizer and the optical axis of the lambda/4 wavelength phase retarder both form a pi/4 included angle or both form a 3 pi/4 included angle.

In an exemplary embodiment of the present disclosure, the light of the real image is in a third polarization state after exiting from the beam splitter, and the light of the virtual image is in the second polarization state after exiting from the beam splitter;

wherein the first polarization state and the second polarization state are both left-handed polarization states, and the third polarization state is a right-handed polarization state;

or, the first polarization state and the second polarization state are both right-handed polarization states, and the third polarization state is a left-handed polarization state.

In an exemplary embodiment of the present disclosure, the display further includes:

and the eyepiece unit is arranged between the third polarizer and the exit pupil position of the display and is used for amplifying the combined image.

the first reflector is arranged on an incident light path of the objective lens unit and used for receiving incident light of the external scene so as to reflect the incident light to the objective lens unit;

the second reflector is arranged between the objective lens unit and the beam splitter and used for receiving emergent light of the objective lens unit so as to reflect the emergent light to the beam splitter;

and the third reflector is arranged on the emergent light path of the ocular unit and is used for receiving the emergent light of the ocular unit to be reflected to the exit pupil position of the display.

In the display provided by the exemplary embodiment of the present disclosure, the light of the real image has the first polarization state through the first polarizer, the light of the virtual image has the second polarization state through the second polarizer, and after the two are combined by the beam splitter to generate the combined image, the light of the real image and the light of the virtual image emitted from the beam splitter may present two different polarization states, and the polarized lights of the two different polarization states may only respectively emit from different polarization regions of the third polarizer, that is, each polarization region may only emit one type of image light. Therefore, the real image cannot be seen in the light emergent area of the virtual image, the virtual image cannot be seen in the light emergent area of the real image, the effect of the virtual image is equivalent to that the virtual image shields the real image at the corresponding position, so that a good virtual image display effect can be obtained, and a real image fusion effect can be provided for a user.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure. It is to be understood that the drawings in the following description are merely exemplary of the disclosure, and that other drawings may be derived from those drawings by one of ordinary skill in the art without the exercise of inventive faculty.

FIG. 1 schematically illustrates a fused image effect map that a head-mounted display is expected to produce;

FIG. 2 schematically illustrates a fused image effect map actually produced by a head mounted display;

FIG. 3 schematically illustrates a first schematic structural diagram of a head mounted display in an embodiment of the disclosure;

FIG. 4 schematically illustrates a schematic plan view of a third polarizer in an embodiment of the present disclosure;

FIG. 5 schematically illustrates a schematic diagram II of a head mounted display according to an embodiment of the disclosure;

fig. 6 schematically shows a schematic cross-sectional structure of the first to third circular polarizers in the embodiment of the present disclosure.

Reference numerals:

101-virtual car; 102-a real physical platform; 301-objective lens unit; 302-micro display; 303-a beam splitter; 304-an eyepiece unit; 305-a first polarizer; 306-a second polarizer; 307-a third polarizer; 308-a first reflector; 309-a second reflector; 310-a third reflector; 401 — a first bias zone; 402-a second bias zone; 501-linear polarizer; 502-1/4 wavelength phase retarders.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the subject matter of the present disclosure can be practiced without one or more of the specific details, or with other methods, components, devices, steps, and the like. In other instances, well-known technical solutions have not been shown or described in detail to avoid obscuring aspects of the present disclosure.

Furthermore, the drawings are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus their repetitive description will be omitted. Some of the block diagrams shown in the figures are functional entities and do not necessarily correspond to physically or logically separate entities. These functional entities may be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different networks and/or processor devices and/or microcontroller devices.

The present example embodiments provide a display, which may be an optical see-through head mounted display, for enabling fusion of virtual and real images. It is to be understood that in other exemplary embodiments of the present disclosure, the display may also be presented in other forms, such as an ear-hang form, etc., i.e., the present disclosure is not particularly limited to the final presentation form of the display. As shown in fig. 3, the optical see-through head mounted display may include:

an objective lens unit 301 for receiving a real image of an external scene;

a microdisplay 302 for generating a virtual image;

a beam splitter 303 for receiving the real image and the virtual image and combining them to produce a combined image;

an eyepiece unit 304 for enlarging the combined image;

a first polarizer 305, disposed between the objective lens unit 301 and the beam splitter 303, for controlling the light of the real image to be in a first polarization state before entering the beam splitter 303;

the second polarizer 306 is arranged between the microdisplay 302 and the beam splitter 303 and used for controlling the light of the virtual image to be in a second polarization state before entering the beam splitter 303;

a third polarizer 307 is disposed on the light path of the beam splitter 303, for example, between the beam splitter 303 and the eyepiece unit 304, as shown in fig. 4, the third polarizer 307 may include a first polarizing region 401 and a second polarizing region 402, and is configured to control the light beams with different polarization states emitted from the beam splitter 303 to be emitted corresponding to the first polarizing region 401 and the second polarizing region 402, respectively.

Wherein the light propagation path of the real image of the external scene is via the objective lens unit 301, the first polarizer 305, the beam splitter 303, the third polarizer 307, and the eyepiece lens unit 304 to the exit pupil position of the head mounted display; the light propagation path of the virtual image is to the exit pupil position of the head mounted display via the second polarizer 306, the beam splitter 303, the third polarizer 307, and the eyepiece unit 304.

It should be noted that: the light of the real image and the light of the virtual image are in the first polarization state and the second polarization state respectively before entering the beam splitter 303, and the two polarization states may be the same polarization state or different polarization states.

In the optical see-through head-mounted display provided by the exemplary embodiment of the present disclosure, after the light of the real image has the first polarization state by the first polarizer 305 and the light of the virtual image has the second polarization state by the second polarizer 306, and the two polarizations are combined by the beam splitter 303 to generate the combined image, the light of the real image and the light of the virtual image emitted from the beam splitter 303 may present two different polarization states, and the two polarized lights of the two different polarization states can only respectively emit corresponding to different polarization regions of the third polarizer 307, that is, each polarization region only corresponds to the light of one image. Therefore, the real image cannot be seen in the light emergent area of the virtual image, the virtual image cannot be seen in the light emergent area of the real image, the effect of the virtual image is equivalent to that the virtual image shields the real image at the corresponding position, so that a good virtual image display effect can be obtained, and a real image fusion effect can be provided for a user.

Based on the above description, in order to ensure the effect of the virtual image blocking the real image, the first polarizing region 401 may be disposed at the center of the third polarizer 307, and the second polarizing region 402 may be disposed at the edge of the third polarizer 307; the first light-polarizing region 401 may be configured to control light of a virtual image to pass through and light of a real image to be cut off, and the second light-polarizing region 402 may be configured to control light of a real image to pass through and light of a virtual image to be cut off.

Thus, the image emitted from the position corresponding to the first polarized light zone 401 is only a virtual image, and the image emitted from the position corresponding to the second polarized light zone 402 is only a real image, so that the fusion effect is that the virtual image blocks the real image behind the virtual image, for example, the virtual car 101 shown in fig. 1 blocks the real physical platform 102 behind the virtual image.

The light of the virtual image generated by the microdisplay 302 may be collimated light, taking into account the scale after image fusion, and the first polarized light region 401 may coincide with the size of the virtual image presented by the microdisplay 302. The micro display 302 may be a liquid crystal display using a collimated light source as a backlight, an organic light emitting diode display capable of emitting collimated light, or a plasma display PDP capable of emitting collimated light. The present embodiment is not limited to a specific type of microdisplay 302.

Preferably, in order to ensure that the real image of the external scene and the virtual image generated by the microdisplay 302 can simultaneously enter the beam splitter 303 to realize image fusion, the distance from the imaging position of the real image of the external scene passing through the objective lens unit 301 to the beam splitter 303 is equal to the distance from the microdisplay 302 to the beam splitter 303.

In the present exemplary embodiment, the light propagation path of the real image and the light propagation path of the virtual image may be controlled by a light path control module composed of a plurality of reflection devices. Specifically, referring to fig. 3, the optical path control module may include:

a first reflector 308 disposed on an incident light path of the objective lens unit 301, for example, between an entrance pupil position of the head-mounted display where an external scene enters the objective lens unit 301, for receiving the incident light of the external scene to reflect to the objective lens unit 301;

a second reflector 309 disposed between the objective lens unit 301 and the beam splitter 303, for receiving the outgoing light of the objective lens unit 301 to reflect to the beam splitter 303;

and a third reflector 310, disposed on an exit light path of the eyepiece unit 304, for example, between the eyepiece unit 304 and an exit pupil position of the head-mounted display, for receiving the exit light of the eyepiece unit 304 to reflect to the exit pupil position of the head-mounted display, i.e., a viewing position where the human eye is located.

The first reflector, the second reflector and the third reflector can be plane reflectors, and the arrangement angle of the plane reflectors and the light rays incident on the reflecting surface can form an included angle of pi/4, so that the propagation direction of the incident light rays can be changed by pi/2.

It should be noted that: the optical path control module may include more than the three reflectors, and the arrangement angles of the three reflectors are not limited thereto. In the present embodiment, as long as the light propagation path of the real image and the light propagation path of the virtual image can be formed by using the reflectors, the specific number and the arrangement angle of the reflectors are not particularly limited. It should be noted that, since the implementation of the technical solution of the present disclosure is based on that the light rays with different polarization states exit from different polarization regions of the third polarizer 307, no matter how the reflector is arranged, the polarization states of the two polarized light incident to the third polarizer 307 should be unchanged.

The operation of the optical see-through head-mounted display is described in two specific embodiments with reference to the accompanying drawings.

In the first embodiment, as shown in fig. 3, the first polarizer 305, the second polarizer 306, and the third polarizer 307 are respectively a first to a third linear polarizer, and the transmission axes of the first polarizing region 401 and the second polarizing region 402 of the third linear polarizer are perpendicular to each other; the transmission axis of the first linear polarizer is parallel to the transmission axis of the second polarizing region 402 of the third linear polarizer, and the transmission axis of the second linear polarizer is parallel to the transmission axis of the first polarizing region 401 of the third linear polarizer.

Based on this, light from the real image of the external scene first enters the head-mounted display, and passes through the objective lens unit 301 after being reflected by the first reflector 308, the light emitted from the objective lens unit 301 is reflected by the second reflector 309 and then imaged between the first linear polarizer and the beam splitter 303, and since the light passes through the first linear polarizer, the natural light from the external scene is converted into first linear polarized light with a first polarization state, and the polarization direction of the first linear polarized light may be perpendicular to the paper surface, for example; meanwhile, the light from the virtual image of the microdisplay 302 is converted into a second linearly polarized light with a second polarization state by the second linearly polarizer, and the polarization direction of the second linearly polarized light can be parallel to the paper surface and horizontal; thus, the light of the real image and the light of the virtual image become two linearly polarized light beams having polarization directions perpendicular to each other before entering the beam splitter 303.

On this basis, since the imaging position of the real image of the external scene is at the same distance from the beam splitter 303 as the microdisplay 302 is from the beam splitter 303, therefore, the real image and the virtual image can enter the beam splitter 303 at the same time to perform image fusion, and the polarization states of the two linearly polarized light beams passing through the beam splitter 303 are not changed, i.e. the light of the real image is still in the first polarization state after exiting from the beam splitter 303, and the light of the virtual image is still in the second polarization state after exiting from the beam splitter 303, the generated combined image passes through the third polarizer 307 in different regions, that is, the polarized light of the virtual image is emitted corresponding to the first polarized region 401, and the polarized light of the real image is emitted corresponding to the second polarized region 402, so that the first polarized region 401 can emit only the light of the virtual image, the second light-deflecting area 402 only emits light of the real image, so that the virtual image can shield the real image behind the virtual image.

Further, the virtual-real fused combined image may be enlarged when passing through the eyepiece unit 304, and the enlarged image may enter human eyes after being reflected by the third reflector 310, so as to present the combined image to a user.

In the second embodiment, as shown in fig. 5 and fig. 6, the first polarizer 305, the second polarizer 306, and the third polarizer 307 are respectively first to third circular polarizers, i.e. respectively composed of a linear polarizer 501 and a λ/4 wavelength phase retarder 502, and the transmission axes of the first polarizing region 401 and the second polarizing region 402 of the third linear polarizer are the same and respectively form an angle of pi/4 and an angle of 3 pi/4 with the optical axis of the λ/4 wavelength phase retarder 502; wherein, the transmission axis of the first linear polarizer and the optical axis of the λ/4 wavelength phase retarder 502 and the transmission axis of the second linear polarizer and the optical axis of the λ/4 wavelength phase retarder 502 both form an included angle of π/4 or an included angle of 3 π/4.

Based on this, light from the real image of the external scene first enters the head-mounted display, and passes through the objective unit 301 after being reflected by the first reflector 308, the light exiting from the objective unit 301 is reflected by the second reflector 309 and then imaged between the first circular polarizer and the beam splitter 303, and since the light passes through the first circular polarizer, the natural light from the external scene is converted into first circularly polarized light having a first polarization state, for example, left-handed polarized light; at the same time, the light from the virtual image of the microdisplay 302 is converted into second circularly polarized light having a second polarization state, e.g., left-polarized light, by the second circular polarizer; thus, the light of the real image and the light of the virtual image become two circularly polarized lights with the same polarization direction before entering the beam splitter 303.

On the basis, since the distance from the imaging position of the real image of the external scene to the beam splitter 303 is equal to the distance from the microdisplay 302 to the beam splitter 303, the real image and the virtual image can enter the beam splitter 303 at the same time to perform image fusion, and the polarization state of the first circularly polarized light changes after being emitted from the beam splitter 303, for example, the light is right-handed polarized light with the third polarization state, the polarization state of the second circularly polarized light does not change, for example, the light is left-handed polarized light with the second polarization state, the combined image generated by the combined image passes through the third polarizer 307 in a partitioning manner, that is, the polarized light of the virtual image is emitted corresponding to the first polarized region 401, the polarized light of the real image is emitted corresponding to the second polarized region 402, so that the first polarized region 401 emits only the light of the virtual image, and the second polarized region 402 emits only the light of the real image, thereby achieving the effect that the virtual image shields the real image behind the virtual image.

It should be noted that: in this embodiment, the first polarization state and the second polarization state are left-handed polarization states, and the third polarization state is right-handed polarization state, but the first polarization state and the second polarization state may be right-handed polarization states, and the third polarization state may be left-handed polarization state.

In addition, when circularly polarized light is formed, the relationship between the transmission axis of the linear polarizer and the optical axis of the λ/4 wavelength phase retarder is not limited to the above, as long as the light of the real image and the light of the virtual image can have the same polarization state before entering the beam splitter 303, and two light beams having different polarization states and emitted from the beam splitter 303 can pass through in a partitioned manner, and the others are not particularly limited.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A display, comprising:

an objective lens unit for receiving a real image of an external scene;

a microdisplay for generating a virtual image;

2. The display of claim 1, wherein the first polarizing region is located at the center of the third polarizer and the second polarizing region is located at the edge of the third polarizer;

3. The display of claim 2, wherein the light of the virtual image generated by the microdisplay is collimated light and the first polarized region is consistent with a size of a virtual image presented by the microdisplay.

4. The display of claim 1, wherein the distance from the imaging position of the real image of the external scene after passing through the objective lens unit to the beam splitter is equal to the distance from the microdisplay to the beam splitter.

5. The display of claim 1, wherein the first polarizer is a first linear polarizer, the second polarizer is a second linear polarizer, and the third polarizer is a third linear polarizer;

6. The display of claim 5, wherein the real image light is in the first polarization state after exiting the beam splitter, and the virtual image light is in the second polarization state after exiting the beam splitter.

7. The display of claim 1, wherein the first polarizer comprises a first linear polarizer and a λ/4 wavelength phase retarder, the second polarizer comprises a second linear polarizer and a λ/4 wavelength phase retarder, and the third polarizer comprises a third linear polarizer and a λ/4 wavelength phase retarder;

8. The display of claim 7, wherein the real image light emerges from the beam splitter in a third polarization state, and the virtual image light emerges from the beam splitter in the second polarization state;

9. The display of claim 1, further comprising:

10. The display of claim 9, further comprising: