Near-to-eye display device and electronic equipment

Abstract

The invention relates to a near-to-eye display device and electronic equipment, the near-to-eye display device comprises a first compensating mirror and an optical waveguide sheet which are sequentially stacked, the optical waveguide sheet is provided with a coupling-in grating and a coupling-out grating, the optical waveguide sheet has bending deformation, the first compensating mirror is arranged on the side close to the human eye, and the coupling-in grating is arranged on the coupling-out grating. The first compensating mirror is used for compensating propagation deviation generated by the first light, the first light is diffracted by the coupling-in grating to enter the optical waveguide sheet and is coupled out by the coupling-out grating after being totally reflected by the optical waveguide sheet, and the propagation deviation generated by the first light is generated based on bending deformation of the optical waveguide sheet.

Description

Technical Field

[0001] The present disclosure relates to optical display technology, and more specifically, to a near-eye display device and an electronic device. Background Art

[0002] Augmented reality and mixed reality technologies are widely used in many industries by combining virtual information with the real world. In the corresponding electronic devices, optical waveguides are regarded as one of the best optical display devices due to their good optical effects and low process difficulty.

[0003] Optical waveguides are divided into geometric waveguides and diffraction waveguides. Considering the weight, volume and process difficulty, diffraction waveguides are considered to have greater potential in the future. The propagation principle of diffraction waveguides is as follows: the diffraction waveguide is provided with an in-coupling grating and an out-coupling grating. Through the in-coupling grating, the light emitted by the optical machine is diffracted into the optical waveguide for total reflection propagation, and then the light is coupled out through the out-coupling grating and enters the human eye.

[0004] In the related art, the diffractive optical waveguide is made of resin material, and the diffractive optical waveguide sheet often adopts a planar structure. When the diffractive optical waveguide sheet is processed and made of resin material, bending deformation is easy to occur, which can affect the imaging quality, making the image seen by the user unclear or offset, affecting the user's viewing experience. Summary of the invention

[0005] An object of the present invention is to provide a new technical solution for a near-eye display device.

[0006] According to a first aspect of the present invention, there is provided a near-eye display device, comprising: a first compensation mirror and an optical waveguide sheet which are sequentially stacked, wherein:

[0007] The optical waveguide sheet is provided with an in-coupling grating and an out-coupling grating, the optical waveguide sheet has a bending deformation, and the first compensation mirror is provided on a side close to the human eye.

[0008] The first compensation mirror is used to compensate for the propagation deviation of the first light, the first light is diffracted by the coupling-in grating into the optical waveguide plate and is coupled out by the coupling-out grating after total reflection at the optical waveguide plate, and the propagation deviation of the first light is generated based on the bending deformation of the optical waveguide plate.

[0009] Optionally, the near-eye display device further comprises a second compensation mirror superimposed on the optical waveguide sheet, wherein the second compensation mirror is arranged on a side close to the environment.

[0010] The second compensation mirror is used to compensate for the propagation deviation of the second light. The second light is incident on the optical waveguide sheet from the environment side and passes through the optical waveguide sheet and the first compensation mirror. The propagation deviation of the second light is generated based on the bending deformation of the optical waveguide sheet and the first compensation mirror.

[0011] Optionally, the morphology of the first compensation mirror is determined based on the morphology of the optical waveguide sheet using light simulation software, wherein the morphology of the first compensation mirror is determined based on the following steps:

[0012] Determining the phase difference of the first light corresponding to different viewing positions of the human eye according to the morphology of the optical waveguide sheet;

[0013] Determining the compensation phase of the corresponding first compensation mirror according to the phase difference of the first light corresponding to the human eye at different viewing positions;

[0014] According to each compensation phase of the first compensation mirror, the morphology of the first compensation mirror is determined.

[0015] Optionally, the phase difference of the first light corresponding to the human eye at different viewing positions is determined based on a first optical path difference and the wavelength of the light, wherein the first optical path difference is determined based on a propagation path difference of the light caused by the bending deformation of the optical waveguide and the refractive index of the optical waveguide.

[0016] Optionally, the phase difference of the first light corresponding to the human eye at different viewing positions and the compensation phase of the corresponding first compensation mirror satisfy the following relationship:

[0017] The sum of the phase difference of the first light corresponding to different viewing positions of the human eye and the compensation phase of the corresponding first compensation mirror is an integer multiple of 2π.

[0018] Optionally, the morphology of the second compensation mirror is determined by using light simulation software based on the morphology of the optical waveguide sheet and the morphology of the first compensation mirror, wherein the morphology of the second compensation mirror is determined based on the following steps:

[0019] Determining the phase difference of the second light corresponding to different viewing positions of the human eye according to the morphology of the optical waveguide sheet and the morphology of the first compensation mirror;

[0020] Determining the compensation phase of the corresponding second compensation mirror according to the phase difference of the second light corresponding to the human eye at different viewing positions;

[0021] The morphology of the second compensation mirror is determined according to each compensation phase of the second compensation mirror.

[0022] Optionally, the phase difference of the second light corresponding to the human eye at different viewing positions is determined based on the second optical path difference and the wavelength of the light, wherein the second optical path difference is determined based on the propagation path difference of the light caused by the bending deformation of the optical waveguide, the refractive index of the optical waveguide, the propagation path difference of the light caused by the set first compensation mirror, and the refractive index of the first compensation mirror.

[0023] Optionally, the phase difference of the second light corresponding to the human eye at different viewing positions and the corresponding compensation phase of the second compensation mirror satisfy the following relationship:

[0024] The sum of the phase difference of the second light corresponding to different viewing positions of the human eye and the compensation phase of the corresponding second compensation mirror is an integer multiple of 2π.

[0025] Optionally, the first compensation mirror and the second compensation mirror completely overlap along a direction corresponding to the superposition setting, and the first compensation mirror and the second compensation mirror do not overlap with the coupling-in grating along a direction corresponding to the superposition setting.

[0026] The sizes of the first compensation mirror and the second compensation mirror are both greater than or equal to the size of the outcoupling grating.

[0027] Optionally, the distance between the first compensation mirror and the optical waveguide sheet, and the distance between the second compensation mirror and the optical waveguide sheet are both less than 50 μm, wherein:

[0028] The distance between the first compensation mirror and the optical waveguide plate, and the distance between the second compensation mirror and the optical waveguide plate are both distances along a direction corresponding to the stacking arrangement.

[0029] According to a second aspect of the present invention, an electronic device is provided, comprising the near-eye display device provided in the first aspect and an optical engine, wherein the optical engine is used to project light onto the coupling-in grating.

[0030] The near-eye display device provided by the present invention solves the problems of unclear and offset imaging caused by bending deformation by providing a first compensation mirror and a second compensation mirror when the optical waveguide sheet is bent and deformed. At the same time, the optical waveguide sheet that has been bent and deformed continues to be utilized, thereby controlling the increase in production costs to a certain extent.

[0031] Features and advantages of the embodiments of the present specification will become apparent from the following detailed description of exemplary embodiments of the present specification with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the specification and, together with the description, serve to explain the principles of the embodiments of the specification.

[0033] Figure 1 is a schematic diagram of a near-eye display device in the prior art.

[0034] Figure 2 FIG. 1 is a schematic diagram of an optical waveguide sheet with bending deformation in the related art.

[0035] Figure 3 is a schematic diagram of a near-eye display device according to an embodiment of the present invention.

[0036] Figure 4 is a schematic diagram of a near-eye display device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] Various exemplary embodiments of the present specification will now be described in detail with reference to the accompanying drawings.

[0038] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the embodiments of the present specification and its application or uses.

[0039] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0040] The optical waveguide provided by the present invention is designed as a planar structure, such as Figure 1 However, during the manufacturing process of the optical waveguide, bending deformation is likely to occur, such as Figure 2 As shown. If the optical waveguide sheet with bending deformation is regarded as defective, the production cost is high. If the optical waveguide sheet with bending deformation is directly used, the imaging quality is affected.

[0041] In order to solve the above technical problems, an embodiment of the present invention provides a near-eye display device. Figure 3 As shown, the near-eye display device includes: a first compensation mirror 310 and an optical waveguide sheet 320 which are stacked in sequence.

[0042] The optical waveguide plate 320 is provided with an in-coupling grating 340 and an out-coupling grating 350. The optical waveguide plate 320 has a bending deformation. The first compensation mirror 310 is provided on a side close to the human eye. Figure 3 As shown, the first compensation mirror 310 is used to compensate for the propagation deviation of the first light. The first light is diffracted by the coupling-in grating into the optical waveguide and is coupled out by the coupling-out grating after total reflection of the optical waveguide. The propagation deviation of the first light is generated based on the bending deformation of the optical waveguide.

[0043] The specific principle of the propagation deviation of the first light caused by the bending deformation of the optical waveguide is as follows: for the same viewing position of the human eye, the propagation path of the light in the optical waveguide without bending deformation and the propagation path of the light in the optical waveguide with bending deformation may deviate, and this deviation makes the image viewed by the human eye unclear and offset. The more times the light is totally reflected in the optical waveguide with bending deformation, the greater the deviation of the light propagation path, making the image viewed by the user less clear and more offset.

[0044] The near-eye display device provided by the embodiment of the present invention solves the problem of unclear and offset optical-mechanical imaging caused by bending deformation by setting a first compensation mirror when the optical waveguide sheet is bent and deformed. At the same time, the optical waveguide sheet that has been bent and deformed continues to be used, thereby controlling the increase in production costs to a certain extent.

[0045] In some embodiments, according to Figure 4 As shown, the near-eye display device further includes a second compensation mirror 330 superimposed on the light waveguide sheet 320. The second compensation mirror 330 is disposed on a side close to the environment.

[0046] The second compensation mirror 320 is used to compensate for the propagation deviation of the second light. The second light is incident on the optical waveguide from the environment side and passes through the optical waveguide and the first compensation mirror. The propagation deviation of the second light is generated based on the bending deformation of the optical waveguide and the first compensation mirror.

[0047] The specific principle of causing the propagation deviation of the second light based on the bending deformation of the optical waveguide and the first compensation mirror is as follows: for the same viewing position of the human eye, based on the optical waveguide without bending deformation, the external light in the environment only passes through the optical waveguide without bending deformation to enter the human eye, and based on the optical waveguide with bending deformation and the first compensation mirror, the external light in the environment passes through the optical waveguide with bending deformation and the first compensation mirror to enter the human eye, so that the propagation path of the light is different, resulting in unclear and offset scenes in the environment seen by the human eye.

[0048] The near-eye display device provided by the embodiment of the present invention solves the problem of unclear and offset optical mechanical imaging caused by bending deformation by setting a first compensation mirror when the optical waveguide sheet is bent and deformed. By setting a second compensation mirror, the problem of unclear and offset external environment scenes viewed by the user is also solved, thereby improving the user experience.

[0049] It should be noted that the bending deformation of the optical waveguide does not exceed the preset bending deformation, so compensation can be performed by setting the first compensation mirror and the second compensation mirror to solve the problem of unclear imaging and offset caused by the bending deformation.

[0050] The first compensation mirror and the second compensation mirror are both optical lenses. Figure 1 The morphology of the first compensation mirror and the second compensation mirror shown is a schematic diagram, and their specific morphologies can be determined using light simulation software.

[0051] In some embodiments, the morphology of the first compensation mirror is determined based on the morphology of the optical waveguide using light simulation software, and the light simulation software is Zemax simulation software.

[0052] The morphology of the first compensation mirror is determined based on the following steps: according to the morphology of the optical waveguide plate, the phase difference of the first light corresponding to the human eye at different viewing positions is determined; according to the phase difference of the first light corresponding to the human eye at different viewing positions, the compensation phase of the corresponding first compensation mirror is determined; according to the compensation phases of the first compensation mirror, the morphology of the first compensation mirror is determined.

[0053] The parameters used to characterize the morphology of the optical waveguide are input into the light simulation software to obtain the phase difference of the first light corresponding to different viewing positions of the human eye. The parameters used to characterize the morphology of the optical waveguide include geometric size parameters and curvature parameters.

[0054] Each eye viewing position corresponds to a phase difference of the first light. The phase difference of the first light corresponding to one of the eye viewing positions can be determined based on the corresponding first optical path difference and the wavelength of the light. The first optical path difference can be determined based on the propagation path difference of the light generated by the bending deformation of the optical waveguide sheet and the refractive index of the optical waveguide sheet.

[0055] The first optical path difference is calculated according to the following formula:

[0056] ΔD1=Δd1×n

[0057] Wherein, ΔD1 is the first optical path difference corresponding to a certain viewing position of a human eye, Δd1 is the propagation path difference of the light generated based on the bending deformation of the optical waveguide sheet, and n is the refractive index of the optical waveguide sheet. The propagation path difference Δd1 of the light generated based on the bending deformation of the optical waveguide sheet can be determined based on the simulation of the light propagation path by light simulation software. It should be noted that the more times the light is totally reflected in the optical waveguide sheet that generates the bending deformation, the greater the propagation path difference of the light.

[0058] The phase difference of the first light is calculated according to the following formula:

[0059]

[0060] in, is the phase difference of the first light, λ is the wavelength of the light, and ΔD1%λ is the remainder of the first optical path difference ΔD1 with respect to the wavelength λ of the light, that is, the remainder obtained by dividing the first optical path difference ΔD1 by the wavelength λ of the light.

[0061] By using light simulation software and determining the shape of the first compensation mirror based on the shape of the optical waveguide sheet, the efficiency and accuracy of determining the shape of the first compensation mirror are improved.

[0062] The phase difference of the first light corresponding to different viewing positions of the human eye and the corresponding compensation phase of the first compensation mirror satisfy the following relationship: the sum of the phase difference of the first light corresponding to different viewing positions of the human eye and the corresponding compensation phase of the first compensation mirror is an integer multiple of 2π. The compensation phase of the first compensation mirror is calculated according to the following calculation formula:

[0063]

[0064] in, is the phase difference of the first light, is the compensation phase of the first compensation mirror, k is an integer, and each phase difference of the first light corresponds to a compensation phase.

[0065] Input each compensation phase of the first compensation mirror into the light simulation software to obtain the morphology of the first compensation mirror. The morphology of the first compensation mirror includes parameters for describing the geometrical dimensions.

[0066] In some embodiments, the morphology of the second compensation mirror is determined based on the morphology of the optical waveguide sheet and the morphology of the first compensation mirror using light simulation software, and the light simulation software is Zemax simulation software.

[0067] The morphology of the second compensation mirror is determined based on the following steps: determining the phase difference of the second light corresponding to different viewing positions of the human eye according to the morphology of the optical waveguide plate and the morphology of the first compensation mirror; determining the corresponding compensation phase of the second compensation mirror according to the phase difference of the second light corresponding to different viewing positions of the human eye; determining the morphology of the second compensation mirror according to each compensation phase of the second compensation mirror.

[0068] The parameters used to characterize the morphology of the optical waveguide sheet and the parameters used to characterize the morphology of the first compensation mirror are input into the light simulation software to obtain the phase difference of the second light corresponding to different viewing positions of the human eye.

[0069] Each eye viewing position corresponds to a phase difference of the second light. The phase difference of the second light corresponding to one of the eye viewing positions can be determined based on the corresponding second optical path difference and the wavelength of the light. The second optical path difference can be determined based on the propagation path difference of the light generated based on the bending deformation of the optical waveguide sheet, the refractive index of the optical waveguide sheet, the propagation path difference of the light generated based on the set first compensation mirror, and the refractive index of the first compensation mirror.

[0070] The second optical path difference is calculated according to the following formula:

[0071] ΔD2=Δd 21 ×n+Δd 22 ×n'

[0072] Among them, ΔD2 is the second optical path difference corresponding to a certain viewing position of the human eye, Δd 21 is the propagation path difference of the light caused by the bending deformation of the optical waveguide, n is the refractive index of the optical waveguide, Δd 22 is the propagation path difference of the light generated by the first compensation mirror, and n' is the refractive index of the first compensation mirror. The propagation path difference Δd of the light generated by the bending deformation of the optical waveguide plate 21 and the propagation path difference Δd of the light generated by the first compensation mirror set 22 Both can be determined based on ray simulation software simulating the light propagation path.

[0073] The phase difference of the second light is calculated according to the following formula:

[0074]

[0075] in, is the phase difference of the second light, λ is the wavelength of the light, and ΔD2%λ is the remainder of the second optical path difference ΔD2 with respect to the wavelength λ of the light, that is, the remainder obtained by dividing the second optical path difference ΔD2 by the wavelength λ of the light.

[0076] The phase difference of the second light corresponding to different viewing positions of the human eye and the corresponding compensation phase of the second compensation mirror satisfy the following relationship: the sum of the phase difference of the second light corresponding to different viewing positions of the human eye and the corresponding compensation phase of the second compensation mirror is an integer multiple of 2π. The compensation phase of the second compensation mirror is calculated according to the following calculation formula:

[0077]

[0078] in, is the phase difference of the second light, is the compensation phase of the second compensation mirror, k is an integer, and each phase difference of the second light corresponds to a compensation phase.

[0079] Input each compensation phase of the second compensation mirror into the light simulation software to obtain the morphology of the second compensation mirror. The morphology of the second compensation mirror includes parameters for describing the geometrical dimensions.

[0080] By using light simulation software, the shape of the second compensation mirror is determined based on the shape of the optical waveguide sheet and the shape of the first compensation mirror, thereby improving the efficiency and accuracy of determining the shape of the second compensation mirror.

[0081] In some embodiments, the first compensation mirror and the second compensation mirror completely overlap along the direction corresponding to the superposition setting, and the first compensation mirror and the second compensation mirror do not overlap with the coupling-in grating along the direction corresponding to the superposition setting, and the sizes of the first compensation mirror and the second compensation mirror are both greater than or equal to the size of the coupling-out grating. In this way, the first compensation mirror and the second compensation mirror can solve the problem of unclear imaging and offset caused by bending deformation, while not affecting the diffraction of light by the coupling-in grating.

[0082] In some embodiments, the distance between the first compensation mirror and the light waveguide sheet, and the distance between the second compensation mirror and the light waveguide sheet are both less than 50 μm. The distance between the first compensation mirror and the light waveguide sheet, and the distance between the second compensation mirror and the light waveguide sheet are both distances along the corresponding direction of the superimposed arrangement. This can reduce the volume of the near-eye display device and improve wearing comfort.

[0083] An embodiment of the present invention provides an electronic device, which includes the near-eye display device provided by any of the above embodiments and an optical engine, wherein the optical engine is used to project light onto an incoupling grating.

[0084] The electronic device may be any one of a VR (Virtual Reality) device, an AR (Augmented Reality) device, and a DLP (Digital Light Procession) device. The AR device may be an AR glasses.

[0085] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For the device embodiment, its related parts can be referred to the partial description of the method embodiment.

[0086] The above describes a specific embodiment of the present specification. Other embodiments are within the scope of the appended claims. The various embodiments of the present specification have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A near-eye display device, characterized in that: include: A first compensation mirror and an optical waveguide sheet are sequentially stacked, wherein: The optical waveguide sheet is provided with an in-coupling grating and an out-coupling grating, the optical waveguide sheet has a bending deformation, and the first compensation mirror is provided on a side close to the human eye. The first compensation mirror is used to compensate for the propagation deviation of the first light, the first light is diffracted by the coupling-in grating into the optical waveguide plate and is coupled out by the coupling-out grating after total reflection at the optical waveguide plate, and the propagation deviation of the first light is generated based on the bending deformation of the optical waveguide plate.

2. The near-eye display device according to claim 1, characterized in that: The near-eye display device further comprises a second compensation mirror arranged to overlap with the optical waveguide sheet, wherein the second compensation mirror is arranged on a side close to the environment. The second compensation mirror is used to compensate for the propagation deviation of the second light. The second light is incident on the optical waveguide sheet from the environment side and passes through the optical waveguide sheet and the first compensation mirror. The propagation deviation of the second light is generated based on the bending deformation of the optical waveguide sheet and the first compensation mirror.

3. The near-eye display device according to claim 1 or 2, characterized in that: The morphology of the first compensation mirror is determined based on the morphology of the optical waveguide sheet using light simulation software, wherein the morphology of the first compensation mirror is determined based on the following steps: Determining the phase difference of the first light corresponding to different viewing positions of the human eye according to the morphology of the optical waveguide sheet; Determining the compensation phase of the corresponding first compensation mirror according to the phase difference of the first light corresponding to the human eye at different viewing positions; According to each compensation phase of the first compensation mirror, the morphology of the first compensation mirror is determined.

4. The near-eye display device according to claim 3, characterized in that: The phase difference of the first light corresponding to different viewing positions of the human eye is determined based on the first optical path difference and the wavelength of the light, wherein the first optical path difference is determined based on the propagation path difference of the light caused by the bending deformation of the optical waveguide and the refractive index of the optical waveguide.

5. The near-eye display device according to claim 3, characterized in that: The phase difference of the first light corresponding to the human eye at different viewing positions and the compensation phase of the corresponding first compensation mirror satisfy the following relationship: The sum of the phase difference of the first light corresponding to different viewing positions of the human eye and the compensation phase of the corresponding first compensation mirror is an integer multiple of 2π.

6. The near-eye display device according to claim 2, characterized in that: The morphology of the second compensation mirror is determined by using light simulation software based on the morphology of the optical waveguide sheet and the morphology of the first compensation mirror, wherein the morphology of the second compensation mirror is determined based on the following steps: Determining the phase difference of the second light corresponding to different viewing positions of the human eye according to the morphology of the optical waveguide sheet and the morphology of the first compensation mirror; Determining the compensation phase of the corresponding second compensation mirror according to the phase difference of the second light corresponding to the human eye at different viewing positions; The morphology of the second compensation mirror is determined according to each compensation phase of the second compensation mirror.

7. The near-eye display device according to claim 6, characterized in that: The phase difference of the second light corresponding to the human eye at different viewing positions is determined based on the second optical path difference and the wavelength of the light, wherein the second optical path difference is determined based on the propagation path difference of the light caused by the bending deformation of the optical waveguide, the refractive index of the optical waveguide, the propagation path difference of the light caused by the set first compensation mirror, and the refractive index of the first compensation mirror.

8. The near-eye display device according to claim 6, characterized in that: The phase difference of the second light corresponding to the human eye at different viewing positions and the compensation phase of the corresponding second compensation mirror satisfy the following relationship: The sum of the phase difference of the second light corresponding to different viewing positions of the human eye and the compensation phase of the corresponding second compensation mirror is an integer multiple of 2π.

9. The near-eye display device according to claim 2, characterized in that: The first compensation mirror and the second compensation mirror completely overlap along a direction corresponding to the superposition setting, and the first compensation mirror and the second compensation mirror do not overlap with the coupling-in grating along a direction corresponding to the superposition setting, The sizes of the first compensation mirror and the second compensation mirror are both greater than or equal to the size of the outcoupling grating.

10. The near-eye display device according to claim 2, characterized in that: The distance between the first compensation mirror and the optical waveguide sheet, and the distance between the second compensation mirror and the optical waveguide sheet are both less than 50 μm, wherein: The distance between the first compensation mirror and the optical waveguide plate, and the distance between the second compensation mirror and the optical waveguide plate are both distances along a direction corresponding to the stacking arrangement.

11. An electronic device, characterized in that: include: A near-eye display device and optical machine as described in any one of claims 1-10, wherein the optical machine is used to project light onto the coupling-in grating.

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