Method and device for obtaining correction parameters of AR imaging system

Abstract

The present application provides a method and device for obtaining correction parameters of an AR imaging system, wherein the method comprises: controlling a display component to emit a correction image, projecting the correction image to an optical machine lens module by a light source, shrinking and expanding the beam through the optical machine lens module, reflecting the beam to an imaging lens module through a waveguide component, and focusing the beam to a camera through the imaging lens module to form an image; obtaining the current distance z between the optical machine lens module and the light source; obtaining the original length w of the correction image L 、Width L , and the original imaging distance z L ; According to the camera imaging, determine the length w of the camera imaging of the correction image C 、Width C , imaging distance z C ; The correction parameters corresponding to the current distance z are calculated using the following first relationship, and the correction parameters include the magnification α(z) and the waveguide optical path deviation β(z). Compared with the prior art, the present application can improve the quality of virtual image interaction between the AR imaging system and the user, so that the user has a stronger sense of immersion and improves the user experience.

Description

Technical Field

[0001] The present application relates to the field of optical testing technology, and in particular to an imaging correction method and device for an AR imaging system. Background Art

[0002] AR (Augmented Reality) technology is to simulate and superimpose physical information (such as visual information, sound, etc.) that is difficult to experience in a certain time and space range in the real world through computers and other scientific technologies, and then apply virtual information to the real world and be perceived by human senses, thereby achieving a sensory experience beyond reality. Augmented reality technology not only displays information in the real world, but also displays virtual information at the same time. The two types of information complement and superimpose each other.

[0003] The projection systems of AR products are composed of display modules, optical machines, lenses, accessories and brackets. The imaging is done by the display module projecting the content onto the lens through the optical machine, and then the lens reflects it to the human eye, allowing people to interact with the virtual image, thereby achieving the function of AR augmented reality.

[0004] It can be seen that the relative assembly accuracy of the display module, optical machine and lens structure is a key factor in determining the AR imaging effect. The tolerances of the display module, optical machine and lens themselves and their assembly will cause errors in imaging distance. In this case, long-term use of AR products will cause users to experience visual fatigue, dizziness and other phenomena, so the accuracy of imaging distance will greatly affect the user experience. Summary of the invention

[0005] The purpose of this application is to provide a method and device for obtaining correction parameters of an AR imaging system, so as to calibrate the AR imaging system and improve the user experience.

[0006] The first aspect of the present application provides a method for obtaining correction parameters of an AR imaging system, comprising:

[0007] The AR imaging system includes a display component, a light source, an optomechanical lens module, a waveguide component and an imaging lens module arranged along an optical path;

[0008] Control the display component to emit a correction image, and the light source projects the correction image to the optical machine lens module, and then the correction image is contracted and expanded by the optical machine lens module, and then reflected to the imaging lens module by the waveguide component, and then focused to the camera by the imaging lens module to form an image; the camera is used to capture the image of the correction image passing through the AR imaging system;

[0009] Obtaining a current distance z between the optomechanical lens module and the light source;

[0010] Get the original length w of the corrected imageL 、Width L , and the original imaging distance z L ;

[0011] According to the imaging on the camera, the length w of the camera imaging of the correction image is determined C 、Width C , imaging distance z C ;

[0012] The correction parameters corresponding to the current distance z are calculated using the following first relationship, wherein the correction parameters include the magnification α(z) and the waveguide optical path deviation β(z);

[0013] The first relationship is as follows:

[0014] α(z)=w C / w L =h C / h L ;

[0015] z C =α(z)*z L +β(z).

[0016] A second aspect of the present application provides a correction parameter acquisition device for an AR imaging system, the device comprising: a control module and an acquisition module;

[0017] The AR imaging system includes a display component, a light source, an optomechanical lens module, a waveguide component and an imaging lens module arranged along an optical path;

[0018] The control module is used to control the display component to emit a correction image, the light source projects the correction image to the optical mechanical lens module, the optical mechanical lens module shrinks and expands the beam, the waveguide component reflects the correction image to the imaging lens module, and the imaging lens module focuses the correction image on the camera; the camera is used to capture the image of the correction image passing through the AR imaging system;

[0019] The acquisition module is used to perform the following steps:

[0020] Obtaining a current distance z between the optomechanical lens module and the light source;

[0021] Get the original length w of the corrected image L 、Width L , and the original imaging distance z L ;

[0022] According to the imaging on the camera, the length w of the camera imaging of the correction image is determined C 、Width C , imaging distance z C;

[0023] The correction parameters corresponding to the current distance z are calculated using the following first relationship, wherein the correction parameters include the magnification α(z) and the waveguide optical path deviation β(z);

[0024] The first relationship is as follows:

[0025] α(z)=w C / w L =h C / h L ;

[0026] z C =α(z)*z L +β(z).

[0027] The present application provides a correction parameter acquisition method and device for an AR imaging system, in which a camera is placed at the exit pupil of the AR imaging system to imitate the human eye and capture the imaging of a correction image. The imaging distance correction parameters and spatial frequency response SFR of the AR imaging system can be obtained based on the imaging of the correction image. The AR imaging system can be calibrated based on the correction parameters and SFR, so that the imaging distance projected by the AR imaging system meets the user's intuition, thereby improving the quality of virtual image interaction between the AR imaging system and the user, allowing the user to have a stronger sense of immersion and improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0029] Figure 1 A schematic diagram of an AR imaging system provided by the present application is shown;

[0030] Figure 2 A flowchart of a method for obtaining correction parameters of an AR imaging system provided by the present application is shown;

[0031] Figure 3 A schematic diagram showing the principle of obtaining correction parameters of an AR imaging system provided by the present application is shown;

[0032] Figure 4 A schematic diagram of an optical path of an AR imaging system with imaging distance variation provided by the present application is shown;

[0033] Figure 5 A flow chart for determining whether the optical machine lens module is out of focus provided by the present application is shown;

[0034] Figure 6 A schematic diagram of the optical path of focusing and defocusing of the optical mechanical lens module provided in the present application is shown;

[0035] Figure 7 A comparison chart of the SFR values ​​of the focusing and defocusing of the optical mechanical lens module provided by the present application is shown;

[0036] Figure 8 A schematic diagram of a correction parameter acquisition device for an AR imaging system provided in the present application is shown. DETAILED DESCRIPTION

[0037] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0038] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by technicians in the field to which this application belongs.

[0039] Figure 1 A schematic diagram of an AR imaging system provided by the present application is shown, such as Figure 1 As shown, the AR imaging system includes a display component 100, a light source 200, an optical machine lens module 300, a waveguide component 400 and an imaging lens module 500 arranged along the optical path. Figure 1 As shown, the present application also places a camera at the exit pupil of the AR imaging system to be corrected to imitate the human eye and capture the image of the correction image.

[0040] The waveguide component 400 includes an input coupling grating 410 , a waveguide 420 , and an output coupling grating 430 .

[0041] Figure 2 A flow chart of a method for obtaining correction parameters of an AR imaging system provided in the present application is shown as follows: Figure 2 As shown, the above method comprises the following steps:

[0042] S101, controlling the display component to emit a correction image, and projecting the correction image to the optomechanical lens module by the light source, and then shrinking and expanding the beam through the optomechanical lens module, and then reflecting it to the imaging lens module through the waveguide component, and then focusing it to the upper image of the camera through the imaging lens module;

[0043] The camera is used to capture the image of the correction image after it passes through the AR imaging system.

[0044] The correction image may be a knife-edge image, and of course other images with correction functions may also be used, which is not limited in the present application.

[0045] S102, obtaining a current distance z between the optical machine lens module 300 and the light source 200;

[0046] S103, obtaining the original length w of the corrected image L 、Width L , and the original imaging distance z L ;

[0047] The imaging distance is the distance between the imaging lens module 500 and the camera imaging, and the original imaging distance z L is the imaging distance of the AR imaging system to be calibrated before calibration.

[0048] S104: Determine the length w of the camera imaging of the correction image according to the imaging on the camera. C 、Width C , imaging distance z C ;

[0049] S105, using the following first relationship to calculate and obtain the correction parameters corresponding to the current distance z, wherein the correction parameters include the magnification α(z) and the waveguide optical path deviation β(z);

[0050] The first relationship is as follows:

[0051] α(z)=w C / w L =h C / h L ;

[0052] z C =α(z)*z L +β(z).

[0053] The first relation can be obtained through the following process:

[0054] Before calibrating the AR imaging system, you can refer to Figure 3 Perform camera imaging distance calibration. After aligning the optomechanical lens module with the camera on the optical axis, input the knife-edge image of the light source in a dark room, image the camera, and adjust the autofocus module of the optomechanical lens module (even if the optomechanical lens module is displaced, changing the distance between the optomechanical lens module and the imaging lens module), obtain the magnification of the knife-edge image at different distances, and define the fitting curve of the camera's standard imaging distance and the knife-edge image magnification, which is the first relationship mentioned above.

[0055] like Figure 1As shown, the optomechanical lens module is on the optical axis, and the optomechanical lens module automatically focuses at the initialization position z0, that is, the current distance between the optomechanical lens module and the light source is z0. At this time, the length, width and imaging distance of the camera imaging of the corrected image are (w C0 ,h C0 , z C0 ), then there will be the following relationship:

[0056] α(z0)=w C0 / w L =h C0 / h L ;z C0 =α(z0)*z L +β(z0).

[0057] The above relationship is used to obtain the magnification α(z0) and waveguide optical path deviation β(z0) of the optomechanical lens module at the initialization position z0. Finally, the correction parameters (α, β) are fed back to the optomechanical lens module to complete the measurement and correction of the imaging distance corresponding to the initialization position z0.

[0058] In some embodiments of the present application, the step of constructing the first relational expression includes:

[0059] Changing the distance between the optical machine lens module and the light source multiple times, with each change amount being ±Δz;

[0060] Record the correction parameters corresponding to each Δz;

[0061] The first relational expression is constructed according to the correction parameters corresponding to each Δz.

[0062] Specifically, the above process of correcting the initialization position z0 is expanded, such as Figure 4 As shown, the distance between the optical machine lens module 300 and the light source 200 is changed by ±Δz, for example, z0-Δz, z0-2Δz, z0-3Δz, and the imaging distance corresponding to each change Δz and the magnification α(z) of the correction image and the waveguide optical path deviation β(z) are recorded, and finally the correction relationship is obtained: C =α(z)*z L +β(z). By feeding back this correction relationship to the optical machine lens module, the correction of the imaging distance is completed, thereby improving the accuracy of the imaging distance.

[0063] In some embodiments of the present application, the correction parameter acquisition method of the above-mentioned AR imaging system may also include the steps of: calculating the spatial frequency response SFR value of the camera imaging of the corrected image; and judging whether the optomechanical lens module is defocused according to the SFR value.

[0064] SFR (Spatial Frequency Response) is mainly used to measure the impact of increasing spatial frequency lines on a single image. It is an evaluation of the resolution of the entire imaging system. The closer the SFR value is to 1, the better the imaging effect of the imaging system.

[0065] Specifically, Figure 5 As shown, the step of judging whether the optical mechanical lens module is out of focus according to the SFR value includes:

[0066] S201, determining whether the SFR value of the camera imaging of the correction image at a preset spatial frequency is less than a standard SFR value; the standard SFR value refers to the SFR value at the preset spatial frequency when the optical-mechanical lens module is focused, which is pre-calibrated;

[0067] S202: If yes, determine that the optical mechanical lens module is out of focus;

[0068] S203: If not, determine whether the optical machine lens module is in focus.

[0069] Specifically, by analyzing the SFR value of the camera imaging of the corrected image, it is possible to determine whether the projection of the optomechanical lens module is on the focusing plane, that is, it is possible to determine whether the optomechanical lens module is defocused or in focus based on the SFR value.

[0070] like Figure 6 As shown, in the left picture, the optomechanical lens module 300 is in focus, which can produce clear camera imaging; in the right picture, the optomechanical lens module 300 is out of focus, and the camera imaging is relatively blurry.

[0071] like Figure 7 As shown in the figure, when the optical machine lens module is out of focus, the SFR value of the camera imaging at the preset spatial frequency is significantly lower than the standard SFR value. For example, the preset spatial frequency is 0.25. Figure 7 As shown, at a spatial frequency of 0.25, the defocused SFR value of the optical mechanical lens module is significantly smaller than the focused SFR value.

[0072] The present application provides a method for obtaining correction parameters of an AR imaging system, in which a camera is placed at the exit pupil of the AR imaging system to imitate the human eye and capture the imaging of a correction image. The imaging distance correction parameters and spatial frequency response SFR of the AR imaging system can be obtained based on the imaging of the correction image. The AR imaging system can be calibrated based on the correction parameters and SFR, so that the imaging distance projected by the AR imaging system meets the user's intuition, thereby improving the quality of virtual image interaction between the AR imaging system and the user, allowing the user to have a stronger sense of immersion and improving the user experience.

[0073] The embodiment of the present application also provides a correction parameter acquisition device for an AR imaging system corresponding to the correction parameter acquisition method for the AR imaging system, such as Figure 8 As shown, the device includes: a control module 101 and an acquisition module 102;

[0074] The AR imaging system includes a display component, a light source, an optomechanical lens module, a waveguide component and an imaging lens module arranged along an optical path;

[0075] The control module 101 is used to control the display component to emit a correction image, and the light source projects the correction image to the optical mechanical lens module, and then the optical mechanical lens module shrinks and expands the beam, and then reflects it to the imaging lens module through the waveguide component, and then focuses it on the camera through the imaging lens module to form an image;

[0076] The acquisition module 102 is used to perform the following steps:

[0077] Obtaining a current distance z between the optomechanical lens module and the light source;

[0078] Get the original length w of the corrected image L 、Width L , and the original imaging distance z L ;

[0079] According to the imaging on the camera, the length w of the camera imaging of the correction image is determined C 、Width C , imaging distance z C ;

[0080] The correction parameters corresponding to the current distance z are calculated using the following first relationship, wherein the correction parameters include the magnification α(z) and the waveguide optical path deviation β(z);

[0081] The first relationship is as follows:

[0082] α(z)=w C / w L =h C / h L ;

[0083] z C =α(z)*z L +β(z).

[0084] In a possible implementation, the acquisition module 102 is further configured to:

[0085] Changing the distance between the optical machine lens module and the light source multiple times, with each change amount being ±Δz;

[0086] Record the correction parameters corresponding to each Δz;

[0087] The AR imaging system is calibrated according to the correction parameters corresponding to each Δz.

[0088] In a possible implementation, the acquisition module 102 is further configured to:

[0089] Calculating the spatial frequency response SFR value of the camera imaging of the corrected image;

[0090] Whether the optical machine lens module is out of focus is determined according to the SFR value.

[0091] In a possible implementation, the acquisition module 102 is specifically configured to:

[0092] Determine whether the SFR value of the camera imaging of the corrected image at a preset spatial frequency is less than a standard SFR value; the standard SFR value refers to the SFR value at the preset spatial frequency when the optical-mechanical lens module is focused;

[0093] If yes, determining that the optical mechanical lens module is out of focus;

[0094] If not, it is determined that the optical-mechanical lens module is in focus.

[0095] In a possible implementation manner, the correction image adopts a knife-edge image.

[0096] The correction parameter acquisition device of the AR imaging system provided in the present application places a camera at the exit pupil of the AR imaging system to imitate the human eye and captures the imaging of the correction image. The imaging distance correction parameters and spatial frequency response SFR of the AR imaging system can be obtained according to the imaging of the correction image. The AR imaging system can be calibrated according to the correction parameters and SFR, so that the imaging distance projected by the AR imaging system meets the user's intuition, improves the quality of virtual image interaction between the AR imaging system and the user, enables the user to have a stronger sense of immersion, and improves the user experience.

[0097] It should be noted that:

[0098] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0099] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various inventive aspects, in the above description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the disclosed method should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the claims below, the inventive aspects are less than all the features of the single embodiment disclosed above. Therefore, the claims following the specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0100] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and in addition they may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0101] In addition, those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims below, any one of the claimed embodiments may be used in any combination.

[0102] The various component embodiments of the present application can be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or digital signal processor (DSP) can be used in practice to implement some or all functions of some or all components in the creation device of the virtual machine according to the embodiment of the present application. The application can also be implemented as a device or device program (e.g., computer program and computer program product) for executing part or all of the methods described herein. Such a program implementing the present application can be stored on a computer-readable medium, or can have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0103] It should be noted that the above embodiments illustrate the present application rather than limit the present application, and that those skilled in the art may design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets should not be constructed as a limitation to the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of multiple such elements. The present application may be implemented by means of hardware including several different elements and by means of a suitably programmed computer. In a unit claim that lists several devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names.

[0104] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for obtaining correction parameters of an AR imaging system, characterized in that: include: The AR imaging system includes a display component, a light source, an optomechanical lens module, a waveguide component and an imaging lens module arranged along an optical path; Control the display component to emit a correction image, and the light source projects the correction image to the optical machine lens module, and then the correction image is contracted and expanded by the optical machine lens module, and then reflected to the imaging lens module by the waveguide component, and then focused to the camera by the imaging lens module to form an image; the camera is used to capture the image of the correction image passing through the AR imaging system; Obtaining a current distance z between the optomechanical lens module and the light source; Get the original length w of the corrected image L 、Width L , and the original imaging distance z L ; According to the imaging on the camera, the length w of the camera imaging of the correction image is determined C 、Width C , imaging distance z C ; The correction parameters corresponding to the current distance z are calculated using the following first relationship, wherein the correction parameters include the magnification α(z) and the waveguide optical path deviation β(z); The first relationship is as follows: α(z)=w C / w L =h C / h L ; With C =α(z)*z L +β(z); The steps of constructing the first relational expression include: Changing the distance between the optical machine lens module and the light source multiple times, with each change amount being ±Δz; Record the correction parameters corresponding to each Δz; The first relational expression is constructed according to the correction parameters corresponding to each Δz.

2. The method according to claim 1, characterized in that The method further comprises: Calculating the spatial frequency response SFR value of the camera imaging of the corrected image; Whether the optical machine lens module is out of focus is determined according to the SFR value.

3. The method according to claim 2, characterized in that The determining whether the optical mechanical lens module is out of focus according to the SFR value includes: Determine whether the SFR value of the camera imaging of the corrected image at a preset spatial frequency is less than a standard SFR value; the standard SFR value refers to the SFR value at the preset spatial frequency when the optical-mechanical lens module is focused; If yes, determining that the optical mechanical lens module is out of focus; If not, it is determined that the optical-mechanical lens module is in focus.

4. The method according to any one of claims 1 to 3, characterized in that The correction image adopts a knife-edge image.

5. A correction parameter acquisition device for an AR imaging system, characterized in that: The device comprises: a control module and an acquisition module; The AR imaging system includes a display component, a light source, an optomechanical lens module, a waveguide component and an imaging lens module arranged along an optical path; The control module is used to control the display component to emit a correction image, the light source projects the correction image to the optical mechanical lens module, the optical mechanical lens module shrinks and expands the beam, the waveguide component reflects the correction image to the imaging lens module, and the imaging lens module focuses the correction image on the camera; the camera is used to capture the image of the correction image passing through the AR imaging system; The acquisition module is used to perform the following steps: Obtaining a current distance z between the optomechanical lens module and the light source; Get the original length w of the corrected image L 、Width L , and the original imaging distance z L ; According to the imaging on the camera, the length w of the camera imaging of the correction image is determined C 、Width C , imaging distance z C ; The correction parameters corresponding to the current distance z are calculated using the following first relationship, wherein the correction parameters include the magnification α(z) and the waveguide optical path deviation β(z); The first relationship is as follows: α(z)=w C / w L =h C / h L ; With C =α(z)*z L +β(z); The acquisition module is further used for: Changing the distance between the optical machine lens module and the light source multiple times, with each change amount being ±Δz; Record the correction parameters corresponding to each Δz; The first relational expression is constructed according to the correction parameters corresponding to each Δz.

6. The device according to claim 5, characterized in that The acquisition module is further used for: Calculating the spatial frequency response SFR value of the camera imaging of the corrected image; Whether the optical machine lens module is out of focus is determined according to the SFR value.

7. The device according to claim 6, characterized in that The acquisition module is specifically used for: Determine whether the SFR value of the camera imaging of the corrected image at a preset spatial frequency is less than a standard SFR value; the standard SFR value refers to the SFR value at the preset spatial frequency when the optical-mechanical lens module is focused; If yes, determining that the optical mechanical lens module is out of focus; If not, it is determined that the optical-mechanical lens module is in focus.

8. The device according to any one of claims 5 to 7, characterized in that The correction image adopts a knife-edge image.

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