Optical system capable of adjusting display and AR (Augmented Reality) equipment

Abstract

The utility model discloses an optical system capable of adjusting display and AR (Augmented Reality) equipment. The optical system comprises a first projection module, a second projection module, a polarization element, a semi-transparent and semi-reflective element and a receiving end, the polarization element is obliquely arranged relative to the first projection module, the second projection module and the receiving end are respectively arranged at two sides of the polarization element, the first projection module comprises a display and a doublet lens, and the doublet lens comprises a first lens and a second lens; the second projection module comprises a third lens, a fourth lens, a fifth lens and a protection element; the semi-transparent and semi-reflective element is attached to the face, close to the polarization element, of the third lens. The distance between the doublet lens and the polarization element is D1, the distance between the doublet lens and the display is D2, the distance between the fourth lens and the fifth lens is D3, and the following conditions are satisfied: 9.465 mm < = D1 < = 13.485 mm, 0.045 mm < = D2 < = 1.323 mm, and 0.199 mm < = D3 < = 0.581 mm. Compared with the prior art, the imaging quality can be improved, the function of adjusting the diopter of the double optical paths is achieved, fatigue and dizziness of eyes of a user are relieved, and the use experience of the user is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of projection display technology, especially to an adjustable display optical system and AR device. BACKGROUND

[0002] With the rapid development of optical technology, the user's requirements for the function and use experience of AR device are also higher and higher, and the reason affecting the use experience of AR device mainly involves the optical system in AR device. The optical system of the existing AR device usually adopts b i rdbath optical display technology, and the existing AR device usually cannot adjust the diopter of real light path and virtual light path at the same time, but adopts the mode of magnetic myopia lens to assist adjustment, which increases the additional cost and also affects the wearing comfort of the user to some extent.

[0003] In view of this, it is necessary to provide an adjustable display optical system and AR device to solve the above problems. UTILITY MODEL CONTENT

[0004] In view of the deficiencies in the prior art, the utility model provides an adjustable display optical system and AR device, which can effectively alleviate the fatigue and dizziness of the user when observing real images and virtual images, effectively correct the aberration of the system, improve the imaging quality, and improve the use experience and comfort of the user.

[0005] To achieve the above purpose, the first aspect of the utility model provides an adjustable display optical system, which comprises a first projection module, a second projection module, a polarization element, a semi-transparent semi-reflective element and a receiving end; the polarization element is inclinedly arranged opposite to the first projection module, the second projection module and the receiving end are arranged on the two sides of the polarization element respectively, the first projection module comprises a display and a double cemented lens arranged between the display and the polarization element, the double cemented lens comprises a first lens and a second lens arranged in sequence away from the display; the second projection module comprises a third lens, a fourth lens, a fifth lens and a protection element arranged in reverse sequence away from the polarization element; the semi-transparent semi-reflective element is attached to one side of the third lens close to the polarization element; the distance between the double cemented lens and the polarization element is D1, the distance between the double cemented lens and the display is D2, the distance between the fourth lens and the fifth lens is D3, and it satisfies: 9.465mm°≤D1≤13.485mm, 0.045mm≤D2≤1.323mm, 0.199mm≤D3≤0.581mm.

[0006] In a preferred embodiment, the effective focal length of the first lens is F1, the effective focal length of the second lens is F2, the effective focal length of the first projection module is F3, and it satisfies: 0.740≤F1 / F3≤0.828, 1.176≤F2 / F3≤1.430.

[0007] In a preferred embodiment, the refractive indices of the first lens and the second lens under D light are N1 and N2 respectively, the Abbe numbers of the first lens and the second lens under D light are V1 and V2 respectively, and satisfy: 1.68≤N1≤1.76, 1.55≤N2≤1.65, 52≤V1≤75, 24≤V2≤35.

[0008] In a preferred embodiment, the radius of curvature of the surface of the second lens close to the polarizing element is R1, the radius of curvature of the cemented surface of the first lens and the second lens is R2, and the radius of curvature of the surface of the first lens close to the display is R3, and satisfy: 25mm≤R1≤40mm, -30mm≤R2≤-18mm, -13mm≤R3≤-20mm.

[0009] In a preferred embodiment, the half horizontal field of view angle of the first projection module is HFOV, the half vertical field of view angle of the first projection module is VFOV, and satisfy: 19°≤HFOV≤23°, 12°≤VFOV≤14°.

[0010] In a preferred embodiment, the effective focal length of the third lens is F4, the effective focal length of the fourth lens is F5, the effective focal length of the fifth lens is F6, and the effective focal length of the second projection module is F7, and satisfy: -0.186≤F4 / F7≤0.241, 0.950≤F5 / F7≤1.340, 0.535≤F6 / F7≤1.219.

[0011] In a preferred embodiment, the refractive indices of the third lens, the fourth lens and the fifth lens under D light are N3, N4 and N5 respectively, the Abbe numbers of the third lens, the fourth lens and the fifth lens under D light are V3, V4 and V5 respectively, and satisfy: 1.53≤N3≤1.58, 1.51≤N4≤1.55, 1.87≤N5≤1.92, 65≤V3≤80, 50≤V4≤60, 25≤V5≤42.

[0012] In a preferred embodiment, the radius of curvature difference of the third lens is R4, the radius of curvature difference of the fourth lens is R5, and the radius of curvature difference of the fifth lens is R6, and satisfy: 11.5mm≤R4≤14.5mm, 1.6mm≤R5≤5mm, 31mm≤R6≤33mm.

[0013] In a preferred embodiment, the diagonal field of view angle of the second projection module is DFOV, and satisfy: 15°≤DFOV≤19°.

[0014] The second aspect of the utility model provides a kind of AR equipment, it includes the optical system of adjustable display in any one of preceding.

[0015] The utility model discloses the beneficial effect lies in: through the dynamic adjustment double -contact lens between the position of display and polarizing element, the distance of dynamic adjustment fourth lens and fifth lens, can realize the function of the diopter adjustable of double light path of optical system, can effectively alleviate the fatigue and the dizziness of user when observing real image and virtual image, simultaneously, through the reasonable collocation lens group, can effectively correct the aberration of system, improve the imaging quality, improve the use experience and the comfort of user. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The structure schematic diagram of the first projection module provided for the utility model embodiment is provided.

[0017] Figure 2 The structure schematic diagram of the second projection module provided for the utility model embodiment is provided.

[0018] Figure 3 The structure schematic diagram of the polarizing element provided for the utility model embodiment is provided.

[0019] Figure 4 The point list of the first projection module provided for the utility model embodiment is provided.

[0020] Figure 5 The field curvature distortion diagram of the first projection module provided for the utility model embodiment is provided.

[0021] Figure 6 The MTF curve diagram of the first projection module provided for the utility model embodiment is provided.

[0022] Figure 7 The point list of the second projection module provided for the utility model embodiment is provided.

[0023] Figure 8 The field curvature distortion diagram of the second projection module provided for the utility model embodiment is provided.

[0024] Figure 9 The MTF curve diagram of the second projection module provided for the utility model embodiment is provided. DETAILED DESCRIPTION

[0025] In the utility model, the terms "arrange", "have", "connect" should be understood in a broad sense. For example, it can be fixed connection, detachable connection, or integral structure, can be mechanical connection, or electrical connection, can be directly connected, or indirectly connected through intermediate media, or the internal communication between two devices, elements or components. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0026] The terms "first", "second", "third", "fourth", "fifth", "sixth", "seventh" and "eighth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features defined with "first", "second", "third", "fourth", "fifth", "sixth", "seventh" and "eighth" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0027] In addition, in addition to being used to represent the orientation or positional relationship, the above-mentioned part of the terms can also be used to represent other meanings, for example, the term "upper" can also be used to represent a certain dependent relationship or connection relationship in some cases. For those skilled in the art, the specific meaning of these terms in the present application can be understood according to the specific situation.

[0028] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be further described in detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and are not used to limit the present application.

[0029] Please refer to Figure 1 With Figure 2 In the present embodiment, the adjustable display optical system includes a first projection module, a second projection module, a polarizing element 30, a half-transmission half-reflection element 40 and a receiving end 50. The polarizing element 30 is arranged obliquely relative to the first projection module, and the second projection module and the receiving end 50 are arranged on the two sides of the polarizing element 30, respectively.

[0030] Among them, the first projection module is a projection module of a virtual image, the second projection module is a projection module of a real image, and the receiving end 50 is a channel for a user to receive the real image and the virtual image. The display 11 can be an LED type light-emitting panel, an LCD type non-self-luminous panel, an LCOS type non-self-luminous panel, etc.

[0031] Specifically, the first projection module includes a display 11 and a double-cemented lens arranged between the display 11 and the polarizing element 30. The double-cemented lens includes a first lens 121 and a second lens 122 arranged in sequence away from the display 11. The second projection module includes a third lens 21, a fourth lens 22, a fifth lens 23 and a protective element 24 arranged in reverse sequence away from the polarizing element 30. The half-transmission half-reflection element 40 is attached to one side of the third lens 21 close to the polarizing element. The distance between the double-cemented lens and the polarizing element 30 is D1, the distance between the double-cemented lens and the display 11 is D2, the distance between the fourth lens 22 and the fifth lens 23 is D3, and it satisfies: 9.465mm°≤D1≤13.485mm, 0.045mm≤D2≤1.323mm, 0.199mm≤D3≤0.581mm.

[0032] In the embodiment, the polarizing element 30 comprises a flat lens 31, a first polarizing unit 32 and a second polarizing unit 33 arranged in sequence on the side of the flat lens 31 close to the half-transmission half-reflection element 40, the first polarizing element 30 being a quarter-wave plate, and the second polarizing unit 33 being a polarized reflection film.

[0033] In the working process of the first projection module, the light rays containing imaging information are emitted from the display 11, and after passing through the doublet lens, the imaging light rays are projected onto the polarizing element 30, and then modulated by the first polarizing unit 32 and the second polarizing unit 33 on the polarizing element 30, and then reflected to the half-transmission half-reflection element 40, and the half-transmission half-reflection element 40 reflects part of the imaging light rays back to the polarizing element 30, and because the state of the imaging light rays has changed, the imaging light rays passing through the polarizing element 30 again can directly pass through the polarizing element 30 to reach the receiving end 50. In the working process of the second projection module, the external light rays containing environmental information are emitted from the outside, and then sequentially pass through the protection element 24, the fifth lens 23, the fourth lens 22 and the third lens 21, and then modulated by the half-transmission half-reflection element 40, and then the external light rays can directly pass through the polarizing element 30 and be projected into the receiving end 50, and the receiving end 50 fuses the received imaging light rays and external light rays, thereby realizing superimposition of the virtual information to be displayed on the basis of the real-world information.

[0034] In the working process of the first projection module, by adjusting the distance between the doublet lens and the polarizing element 30, that is, by adjusting the sizes of D1 and D2, the light path system of the first projection module can be adjusted in the range of 0D to -5D diopter; in the working process of the second projection module, by adjusting the distance between the fourth lens 22 and the fifth lens 23, the light path system of the second projection module can be adjusted in the range of 2D to -5D diopter, thereby realizing the dual light path diopter adjustment function of the overall optical system.

[0035] It can be understood that by dynamically adjusting the position of the doublet lens between the display 11 and the polarizing element 30 and dynamically adjusting the distance between the fourth lens 22 and the fifth lens 23, the dual light path diopter adjustment function of the optical system can be realized, which can effectively relieve the fatigue and dizziness of the user when observing the real image and the virtual image. At the same time, by reasonably configuring the lens group, the aberration of the system can be effectively corrected, the imaging quality can be improved, and the use experience and comfort of the user can be improved.

[0036] Further, in one embodiment, the effective focal length of the first lens 121 is F1, the effective focal length of the second lens 122 is F2, and the effective focal length of the first projection module is F3, and the following conditions are satisfied: 0.740≤F1 / F3≤0.828, 1.176≤F2 / F3≤1.430. Wherein, the first lens 121 is a meniscus lens, and the second lens 122 is a double convex lens.

[0037] The refractive index of the first lens 121 and the second lens 122 under D light is N1 and N2 respectively, the Abbe number of the first lens 121 and the second lens 122 under D light is V1 and V2 respectively, and the following conditions are satisfied: 1.68≤N1≤1.76, 1.55≤N2≤1.65, 52≤V1≤75, 24≤V2≤35.

[0038] The radius of curvature of the surface of the second lens 122 close to the polarizing element 30 is R1, the radius of curvature of the cemented surface of the first lens 121 and the second lens 122 is R2, and the radius of curvature of the surface of the first lens 121 close to the display 11 is R3, and the following conditions are satisfied: 25mm≤R1≤40mm, -30mm≤R2≤-18mm, -13mm≤R3≤-20mm.

[0039] The half horizontal field of view of the first projection module is HFOV, and the half vertical field of view of the first projection module is VFOV, and the following conditions are satisfied: 19°≤HFOV≤23°, 12°≤VFOV≤14°.

[0040] Specifically, please refer to Figure 4 , Figure 4 The point spread function of the virtual projection light path corresponding to the first projection module. From the information in Figure 4 , it can be seen that the virtual projection light path corresponding to the first projection module has 12 fields of view, and the root mean square radii of the 12 fields of view are 2.591um, 5.158um, 5.139um, 5.066um, 5.083um, 6.403um, 6.453um, 7.082um, 5.814um, 5.820um, 7.093um and 6.557um respectively when the diopter is 0D. That is, the root mean square radii of the point spread functions corresponding to all fields of view are below 8um. When the diopter is in the range of 0D to -5D, the root mean square radii of the virtual projection light path corresponding to the first projection module change, but the root mean square radii remain within two pixel sizes and can be accepted by the human eye.

[0041] Please refer to Figure 5 , Figure 5 The field curvature and distortion map of the virtual projection light path corresponding to the first projection module. From the information in Figure 5The information indicates that the field curvature of the virtual projection optical path corresponding to the first projection module is less than 0.08 mm, and the distortion value within the entire field of view does not exceed 5%. When adjusting the diopter within the range of 0D to -5D, the field curvature of the virtual projection optical path corresponding to the first projection module remains within 0.08 mm, with distortions of 3.94%, 2.75%, 1.97%, 1.21%, 0.61%, and 0.60%, respectively, which meets the design requirements and can be further corrected using subsequent anti-distortion algorithms.

[0042] Please refer to Figure 6 , Figure 6 The MTF curve of the virtual projection optical path corresponding to the first projection module at 0D is given by... Figure 6 The information indicates that the optical transfer function (OPF) value of the virtual projection optical path corresponding to the first projection module is greater than 0.1 at 67 lp / mm in the full field of view, which means that the image quality and resolution meet the design requirements. Within the diopter range of 0D to -5D, the OPF curve changes, but it remains greater than 0.1 at 67 lp / mm, indicating relatively good image quality.

[0043] It is understandable that by setting the optical parameters of the first lens 121, the second lens 122, and the first projection module as a whole, the chromatic aberration of the optical path can be effectively corrected and the distortion of the image can be improved, thereby ensuring the imaging quality of the first projection module and improving the user experience.

[0044] Furthermore, in one embodiment, the effective focal length of the third lens 21 is F4, the effective focal length of the fourth lens 22 is F5, the effective focal length of the fifth lens 23 is F6, and the effective focal length of the second projection module is F7, satisfying: -0.186≤F4 / F7≤0.241, 0.950≤F5 / F7≤1.340, and 0.535≤F6 / F7≤1.219. The third lens is a positive forward meniscus lens, the fourth lens 22 is a biconvex lens, and the fifth lens 23 is a biconcave lens.

[0045] The refractive indices of the third lens 21, the fourth lens 22, and the fifth lens 23 under D light are N3, N4, and N5, respectively, and the Abelian numbers of the third lens 21, the fourth lens 22, and the fifth lens 23 under D light are V3, V4, and V5, respectively, and satisfy the following: 1.53≤N3≤1.58, 1.51≤N4≤1.55, 1.87≤N5≤1.92, 65≤V3≤80, 50≤V4≤60, and 25≤V5≤42.

[0046] The curvature radius difference of the third lens 21 is R4, the curvature radius difference of the fourth lens 22 is R5, and the curvature radius difference of the fifth lens 23 is R6, and satisfy: 11.5mm≤R4≤14.5mm, 1.6mm≤R5≤5mm, 31mm≤R6≤33mm. Wherein, the curvature radius difference of the third lens 21 is the difference between the curvature radius of the front surface of the third lens 21 and the back surface of the third lens 21; the curvature radius difference of the fourth lens 22 is the difference between the curvature radius of the front surface of the fourth lens 22 and the back surface of the fourth lens 22; the curvature radius difference of the fifth lens 23 is the difference between the curvature radius of the front surface of the fifth lens 23 and the back surface of the fifth lens 23.

[0047] The diagonal field of view of the second projection module is DFOV, and satisfies: 15°≤DFOV≤19°.

[0048] Specifically, please refer to Figure 7 , Figure 7 The point spread diagram of the real projection light path corresponding to the second projection module is shown in FIG. 6. Figure 7 As can be seen from FIG. 6, the real projection light path corresponding to the second projection module has six fields of view, and the root mean square radii of the six fields of view are 17.049um, 17.840um, 9.309um, 7.844um, 7.634um and 10.862um respectively when the diopter is 0D, that is, the root mean square radii of the point spread diagrams of all fields of view are less than 18um. Within the range of diopter from 2D to -5D, the root mean square radii of the real projection light path corresponding to the second projection module change, but the size of the diffraction spot can be accepted by the human eye.

[0049] Please refer to Figure 8 , Figure 8 The field curvature and distortion diagram of the real projection light path corresponding to the second projection module is shown in FIG. 7. Figure 8 As can be seen from FIG. 7, when the diopter is 0D, the field curvature of the real projection light path corresponding to the second projection module is less than 0.4mm, and the distortion value within the full field of view is not more than 5%. When the diopter is adjusted within the range of -2D to 5D, the field curvature of the real projection light path corresponding to the second projection module still remains within 0.4mm, and the distortion is 4.43%, 4.47%, 4.53% and 4.39% respectively, which meets the design requirements and can be further corrected by subsequent anti-distortion algorithm.

[0050] Please refer to Figure 9 , Figure 9 The MTF curve diagram of the real projection light path corresponding to the second projection module at 0D is shown in FIG. 8. Figure 9It can be known from the information in the table that the optical transfer function value of the real projection light path corresponding to the second projection module is greater than 0.2 at 30 lp / mm under the full field of view, so that the image quality and resolution meet the design requirements. When the diopter is in the range of 2D to-5D, the optical transfer function curve changes, but is still greater than 0.15 at 30 lp / mm, that is, the imaging quality is relatively good.

[0051] It can be understood that by setting the optical parameter information of the third lens 21, the fourth lens 22, the fifth lens 23 and the second projection module as a whole, the chromatic aberration of the light path and the distortion of the imaging can be effectively corrected, and the imaging quality of the second projection module is ensured, and the use experience of the user is improved.

[0052] In summary, the utility model discloses a dynamic adjustment double cemented lens between the position of display 11 and polarizing element 30, and the distance between the fourth lens 22 and the fifth lens 23 is dynamically adjusted, so that the function of the optical system of double light path diopter adjustable can be realized, the fatigue and dizziness of the user when observing the real image and virtual image can be effectively relieved, and simultaneously, by reasonably configuring the lens group, the aberration of the system can be effectively corrected, the imaging quality is improved, and the use experience and comfort of the user are improved.

[0053] The second aspect of the utility model provides an AR device, which comprises the adjustable display optical system, so that the fatigue and dizziness of the user when observing the real image and virtual image can be effectively relieved, the aberration of the system can be effectively corrected, the imaging quality is improved, and the use experience and comfort of the user are improved.

[0054] The above is only the specific embodiment of the application, and it should be pointed out that for ordinary skilled persons in the technical field, some improvements and refinements can be made without departing from the principles of the application, and these improvements and refinements should also be regarded as the protection scope of the application.

Claims

1. An optical system for adjustable display, characterized by, The first projection module, the second projection module, the polarization element, the half-transmission half-reflection element and the receiving end are included; the polarization element is arranged obliquely relative to the first projection module, the second projection module and the receiving end are arranged on the two sides of the polarization element respectively, the first projection module includes a display and a double-cemented lens arranged between the display and the polarization element, the double-cemented lens includes a first lens and a second lens arranged in sequence away from the display; the second projection module includes a third lens, a fourth lens, a fifth lens and a protective element arranged in reverse sequence away from the polarization element; the half-transmission half-reflection element is attached to one side of the third lens close to the polarization element; the distance between the double-cemented lens and the polarization element is D1, the distance between the double-cemented lens and the display is D2, the distance between the fourth lens and the fifth lens is D3, and the following conditions are met: 9.465mm°≤D1≤13.485mm, 0.045mm≤D2≤1.323mm, 0.199mm≤D3≤0.581mm.

2. The tunable displayed optical system of claim 1, wherein, The effective focal length of the first lens is F1, the effective focal length of the second lens is F2, and the effective focal length of the first projection module is F3, and the following conditions are met: 0.740≤F1 / F3≤0.828, 1.176≤F2 / F3≤1.

430.

3. The tunable display optical system of claim 1, wherein, The refractive index of the first lens and the second lens under D light is N1 and N2 respectively, the Abbe number of the first lens and the second lens under D light is V1 and V2 respectively, and the following conditions are met: 1.68≤N1≤1.76, 1.55≤N2≤1.65, 52≤V1≤75, 24≤V2≤35.

4. The tunable display optical system of claim 1, wherein, The radius of curvature of one side of the second lens close to the polarization element is R1, the radius of curvature of the cemented surface of the first lens and the second lens is R2, and the radius of curvature of one side of the first lens close to the display is R3, and the following conditions are met: 25mm≤R1≤40mm, -30mm≤R2≤-18mm, -13mm≤R3≤-20mm.

5. The tunable display optical system of claim 1, wherein, The half horizontal field of view of the first projection module is HFOV, the half vertical field of view of the first projection module is VFOV, and the following conditions are met: 19°≤HFOV≤23°, 12°≤VFOV≤14°.

6. The tunable display optical system of claim 1, wherein, The effective focal length of the third lens is F4, the effective focal length of the fourth lens is F5, the effective focal length of the fifth lens is F6, and the effective focal length of the second projection module is F7, and the following conditions are met: -0.186≤F4 / F7≤0.241, 0.950≤F5 / F7≤1.340, 0.535≤F6 / F7≤1.

219.

7. The tunable display optical system of claim 1, wherein, The refractive indexes of the third lens, the fourth lens and the fifth lens under D light are N3, N4 and N5 respectively, the Abbe numbers of the third lens, the fourth lens and the fifth lens under D light are V3, V4 and V5 respectively, and satisfy: 1.53≤N3≤1.58, 1.51≤N4≤1.55, 1.87≤N5≤1.92, 65≤V3≤80, 50≤V4≤60, 25≤V5≤42.

8. The tunable display optical system of claim 1, wherein, The curvature radius difference of the third lens is R4, the curvature radius difference of the fourth lens is R5, and the curvature radius difference of the fifth lens is R6, and satisfy: 11.5mm≤R4≤14.5mm, 1.6mm≤R5≤5mm, 31mm≤R6≤33mm.

9. The tunable display optical system of claim 1, wherein, The diagonal field of view angle of the second projection module is DFOV, and satisfy: 15°≤DFOV≤19°.

10. An AR device, comprising: An optical system comprising the adjustable display of any one of the preceding claims 1 to 9.

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