Visual system

Abstract

The utility model discloses a visual system. The visual system comprises a lens cone, an optical element group and a spacer group, wherein the optical element group and the spacer group are arranged in the lens cone; the optical element group comprises a first lens with positive focal power, a reflective polarizing element, a quarter-wave plate, a second lens with focal power and a third lens with positive focal power which are sequentially arranged from the first side to the second side along the optical axis; the first side surface of the first lens is a convex surface, and the second side surface is a plane; the first side surface of the second lens is a convex surface; the second side surface of the third lens is a convex surface; a spacer group including a lens barrel auxiliary spacer disposed on a first side of the first lens and in contact with the first side of the first lens, and a first spacer disposed between the first lens and the second lens; wherein the curvature radius R1 of the first side surface of the first lens and the curvature radius R3 of the first side surface of the second lens satisfy 0.1 lt; r1 / R3lt; 0.6 part; and the inner diameter d0bm of the second side surface of the lens barrel auxiliary spacer and the inner diameter d1m of the second side surface of the first spacer satisfy: 1.0 lt; d < 1 > m / d < 0 > bmlt; and 1.2.

Description

Technical Field

[0001] The present application relates to the field of optical devices, and particularly to a catadioptric optical system. Background Art

[0002] With the proposal of the concept of the metaverse, the virtual reality technology and augmented reality technology of human-computer interaction have迎来了第二次发展的契机。目视系统作为人机交互的重要入口,在其中发挥着关键作用。

[0003] Traditional visual systems include aspherical lenses or Fresnel lenses, which have problems such as a relatively long body length, a relatively heavy weight, and a center of gravity position being靠前等问题,会严重影响用户的佩戴体验感。为了提升用户的佩戴体验感,目视系统可设计成具有两片透镜的折反式光学系统,然而,具有两片透镜的折反式光学系统的外视场画面比较模糊,成像质量较差。 Utility Model Content

[0004] The present application provides a visual system that can at least solve or partially solve at least one problem or other problems existing in the prior art.

[0005] One aspect of the present application provides such a visual system, which includes a lens barrel and an optical element group and a spacer group disposed in the lens barrel; the optical element group includes a first lens with a positive optical power, a reflective polarizing element, a quarter-wave plate, a second lens with an optical power, and a third lens with a positive optical power arranged in sequence along the optical axis from the first side to the second side; the first side of the first lens is a convex surface, and the second side is a flat surface; the first side of the second lens is a convex surface; the second side of the third lens is a convex surface; the spacer group includes a lens barrel auxiliary spacer disposed on the first side of the first lens and in contact with the first side of the first lens and a first spacer disposed between the first lens and the second lens; the radius of curvature R1 of the first side of the first lens and the radius of curvature R3 of the first side of the second lens satisfy: 0.1 < R1 / R3 < 0.6; and the inner diameter d0bm of the second side of the lens barrel auxiliary spacer and the inner diameter d1m of the second side of the first spacer satisfy: 1.0 < d1m / d0bm < 1.2.

[0006] According to an exemplary embodiment of the present application, the radius of curvature R6 of the second side of the third lens and the inner diameter d0m of the second side end face of the lens barrel satisfy: -2.0 < R6 / d0m < -1.1.

[0007] According to an exemplary embodiment of the present application, the effective focal length f1 of the first lens and the outer diameter D0s of the first side end face of the lens barrel satisfy: 2.7 < f1 / D0s < 3.1.

[0008] It should be noted that there are some Chinese characters in the original text that seem to be incorrect or incomplete in the "迎来了第二次发展的契机。目视系统作为人机交互的重要入口,在其中发挥着关键作用。" and "靠前等问题,会严重影响用户的佩戴体验感。为了提升用户的佩戴体验感,目视系统可设计成具有两片透镜的折反式光学系统,然而,具有两片透镜的折反式光学系统的外视场画面比较模糊,成像质量较差。" parts. I translated them as they are, but it's recommended to check and correct the original text for more accurate translation.According to an exemplary embodiment of the present application, the inner diameter d0s of the first side end surface of the lens barrel and the inner diameter d0m of the second side end surface of the lens barrel satisfy: 1.2 <d0m / d0s<1.6。

[0009] According to an exemplary embodiment of the present application, the total effective focal length f of the visual system and the outer diameter D0bm of the second side of the auxiliary spacer of the lens barrel satisfy: 1.9 <D0bm / f<2.7。

[0010] According to an exemplary embodiment of the present application, the maximum length L of the lens barrel along the optical axis, the center thickness CT2 of the second lens on the optical axis, and the center thickness CT3 of the third lens on the optical axis satisfy: 0.9 <L / (CT2+CT3)<1.4。

[0011] According to an exemplary embodiment of the present application, the entrance pupil diameter EPD of the visual system, the inner diameter d1s of the first side of the first spacer, and the inner diameter d0bs of the first side of the lens barrel auxiliary spacer satisfy: 1.2 <EPD / (d1s-d0bs)<2.6。

[0012] According to an exemplary embodiment of the present application, the combined focal length fz of the first lens, the reflective polarizing element and the quarter-wave plate and the outer diameter D0bs of the first side surface of the lens barrel auxiliary spacer satisfy: 2.8 <fz / D0bs<3.2。

[0013] According to an exemplary embodiment of the present application, the axial distance TD from the first side surface of the first lens to the second side surface of the third lens and the outer diameter D0m of the second side end surface of the lens barrel satisfy: 2.9 <D0m / TD<4.1。

[0014] According to an exemplary embodiment of the present application, the refractive index N1 of the first lens, the refractive index N2 of the second lens, the outer diameter D1s of the first side surface of the first spacer, and the outer diameter D1m of the second side surface of the first spacer satisfy: 1.0<(N2 / N1)×(D1m / D1s)<1.2.

[0015] According to an exemplary embodiment of the present application, the spacer group also includes a second spacer placed between the second lens and the third lens; wherein the on-axis distance T12 from the second side surface of the first lens to the first side surface of the second lens, the maximum thickness CP1 of the first spacer, and the interval EP12 between the first spacer and the second spacer along the optical axis satisfy: 4.3<(CP1+EP12) / T12<8.0.

[0016] According to an exemplary embodiment of the present application, the spacer group further includes a second spacer disposed between the second lens and the third lens; wherein, the effective focal length f3 of the third lens, the inner diameter d2m of the second side surface of the second spacer, and the outer diameter D2m of the second side surface of the second spacer satisfy: 0.5 < f3 / (d2m + D2m) < 2.7.

[0017] According to an exemplary embodiment of the present application, the spacer group further includes a second spacer disposed between the second lens and the third lens; wherein, the combined focal length f23 of the second lens and the third lens, the inner diameter d2s of the first side surface of the second spacer, and the outer diameter D2s of the first side surface of the second spacer satisfy: 0.8 < (d2s + D2s) / f23 < 1.2.

[0018] According to an exemplary embodiment of the present application, the spacer group further includes a second spacer disposed between the second lens and the third lens; wherein, the maximum thickness CP0b of the barrel auxiliary spacer, the maximum thickness CP1 of the first spacer, and the maximum thickness CP2 of the second spacer satisfy: 1.5 < (CP0b + CP1) / CP2 < 2.1.

[0019] The visual system provided by the present application is configured as a catadioptric optical system with three lenses, effectively shortening the body length of the visual system and avoiding the problems of blurred outer field images and poor imaging quality caused by the visual system having two lenses. When the visual system satisfies "0.1 < R1 / R3 < 0.6", by restricting the ratio of the inner diameter of the second side surface of the first spacer to the inner diameter of the second side surface of the barrel auxiliary spacer within a reasonable range, it is beneficial to improve the processability of the first spacer and the barrel auxiliary spacer, and at the same time, it is also beneficial to improve the assembly stability of the first lens and the second lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Other features, objects, and advantages of the present application will become more apparent by reading the detailed description of the non-limiting embodiments with reference to the following drawings. Among them:

[0021] Figure 1 Shows a schematic diagram of parameter markings of the visual system according to the present application;

[0022] Figure 2 Shows a schematic structural diagram of the visual system according to Embodiment 1 of the present application;

[0023] Figure 3 Shows a schematic structural diagram of the visual system according to Embodiment 2 of the present application;

[0024] Figure 4 Shows a schematic structural diagram of the visual system according to Embodiment 3 of the present application;

[0025] Figure 5 A schematic diagram of the structure of a visual system according to Embodiment 4 of the present application is shown;

[0026] FIG. 6A to FIG. 6C The axial chromatic aberration curve, astigmatism curve and distortion curve of the visual system according to Embodiments 1, 2, 3 and 4 of the present application are respectively shown;

[0027] Figure 7 A schematic diagram of the structure of a visual system according to Embodiment 5 of the present application is shown;

[0028] Figure 8 A schematic diagram of the structure of a visual system according to Embodiment 6 of the present application is shown;

[0029] 9A to 9C The axial chromatic aberration curve, the astigmatism curve and the distortion curve of the visual system according to Examples 5 and 6 of the present application are respectively shown;

[0030] Fig.10 A schematic diagram of the structure of a visual system according to Embodiment 7 of the present application is shown;

[0031] Fig.11 A schematic diagram of the structure of a visual system according to Embodiment 8 of the present application is shown; and

[0032] FIG. 12A to FIG. 12C The axial chromatic aberration curve, astigmatism curve and distortion curve of the visual system according to Examples 7 and 8 of the present application are respectively shown. DETAILED DESCRIPTION

[0033] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of exemplary embodiments of the present application, and do not limit the scope of the present application in any way. Throughout the specification, the same figure numerals refer to the same elements.

[0034] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0035] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0036] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the first side (e.g., the human eye side) is called the first side surface of the lens, and the surface of each lens closest to the second side (e.g., the display screen side) is called the second side surface of the lens.

[0037] It should also be understood that the terms "include", "comprising", "having", "including" and / or "comprising", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when describing embodiments of the present application, the term "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0038] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as those commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0039] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0040] The features, principles and other aspects of the present application are described in detail below.

[0041] refer to Figures 2 to 5 , Figure 7 , Figure 8 , Fig.10 and Fig.11 The first aspect of the present application provides a visual system which may include an optical element group, which may include a first lens, a reflective polarizing element, a quarter-wave plate, a second lens and a third lens arranged in sequence from the first side to the second side along the optical axis.

[0042] The visual system provided in the present application is configured as a catadioptric optical system with three lenses, which effectively shortens the main body length of the visual system and avoids the problems of blurred external field of view and poor imaging quality caused by the visual system having two lenses.

[0043] In an exemplary embodiment, the first lens may have positive optical power. The second lens may have positive optical power or negative optical power. The third lens may have positive optical power. Reasonable allocation of the optical power of the first lens, the second lens, and the third lens is conducive to improving the external field of view performance of the visual system.

[0044] In an exemplary embodiment, the first side surface of the first lens may be a convex surface, and the second side surface may be a flat surface.

[0045] In example embodiments, the first side surface of the second lens may be a convex surface.

[0046] In example embodiments, the second side surface of the third lens may be a convex surface.

[0047] In an exemplary embodiment, the visual system may further include a lens barrel. The lens barrel includes a first side end surface, a second side end surface, an outer annular surface, and an inner annular surface, wherein the end surface of the lens barrel closest to the first side is the first side end surface of the lens barrel, and the end surface of the lens barrel closest to the second side is the second side end surface of the lens barrel; in a direction perpendicular to the optical axis, the surface of the lens barrel farthest from the optical axis is the outer annular surface, and the surface of the lens barrel closest to the optical axis is the inner annular surface. In the example, the optical element group is placed in the lens barrel.

[0048] In an exemplary embodiment, the visual system may further include a spacer group placed in the lens barrel. The spacer group includes one or more of a lens barrel auxiliary spacer, a first spacer, and a second spacer. The lens barrel auxiliary spacer may be placed between the first side end of the lens barrel and the first lens, for example, the lens barrel auxiliary spacer is placed on the first side of the first lens and at least partially contacts the first side of the first lens. The first spacer may be placed between the first lens and the second lens, for example, the first spacer is at least partially in contact with the second side of the first lens or the first side of the second lens. The second spacer may be placed between the second lens and the third lens, for example, the second spacer is at least partially in contact with the second side of the second lens or the first side of the third lens. The reasonable use of spacers can effectively avoid stray light risks, reduce interference with image quality, and thus improve the imaging quality of the visual system.

[0049] In an exemplary embodiment, the first side may be the human eye side, and the second side may be the display screen side. Accordingly, the first side of each element (first lens, second lens, third lens, reflective polarizing element, quarter wave plate) may be referred to as the side near the human eye, and the second side may be referred to as the side near the screen.

[0050] In an exemplary embodiment, the reflective polarizing element and the quarter wave plate are laminated to form a film layer, and the laminated film layer is attached to the second side surface of the first lens, wherein the reflective polarizing element is located on the first side surface of the quarter wave plate. By laminating the reflective polarizing element and the quarter wave plate together to form a film layer, the number of attached surfaces of the film layer can be reduced, and the attachment yield of the film layer can be improved.

[0051] As an example, the second side surface of the first lens can be a plane, and the film layer formed by laminating the reflective polarizing element and the quarter-wave plate is attached to the second side surface of the first lens. Adopting a planar film laminating method to attach the composite film layer to the plane is conducive to improving the stability of the film layer after attachment, thereby improving the external field of view performance of the visual system.

[0052] In an exemplary embodiment, the visual system may further include a partial reflective layer, which may be attached to the second side surface of the third lens. The partial reflective layer has a semi-transmissive and semi-reflective effect on light. By providing a partial reflective layer on the second side surface of the third lens, and combining a reflective polarizing element and a quarter-wave plate, the light can be refracted multiple times, effectively reducing the length of the main body of the visual system.

[0053] In an exemplary embodiment, the visual system may further include an aperture, which is disposed between the first side and the first lens. The image light on the display screen is refracted and reflected multiple times by the third lens, the second lens, the quarter wave plate, the reflective polarizing element, the first lens, etc., and is finally projected to the user's eyes.

[0054] In an exemplary embodiment, an image surface may be provided on the second side of the visual system, and a display screen may be provided on the image surface. The image light from the display screen sequentially passes through the third lens, the second lens, and the quarter-wave plate to reach the reflective polarizing element located on the second side of the first lens, and then reflects at the reflective polarizing element to form a first reflected image light. The first reflected image light passes through the quarter-wave plate, the second lens, the third lens and reaches the partial reflective layer located on the second side of the third lens, and then reflects at the partial reflective layer to form a second reflected image light. The second reflected image light sequentially passes through the third lens, the second lens, the quarter-wave plate, the reflective polarizing element, the first lens to the aperture and is finally projected into the user's eyes. The visual system provided in the present application folds the required optical path without affecting the projection quality by combining light reflection and refraction, thereby effectively shortening the main body length of the visual system.

[0055] In an exemplary embodiment, the radius of curvature R1 of the first side surface of the first lens and the radius of curvature R3 of the first side surface of the second lens may satisfy: 0.1 < R1 / R3 < 0.6; the inner diameter d0bm of the second side surface of the barrel auxiliary spacer and the inner diameter d1m of the second side surface of the first spacer may satisfy: 1.0 < d1m / d0bm < 1.2. When the visual system satisfies "0.1 < R1 / R3 < 0.6", by restricting the ratio of the inner diameter of the second side surface of the first spacer to the inner diameter of the second side surface of the barrel auxiliary spacer within a reasonable range, it is beneficial to improve the processability of the first spacer and the barrel auxiliary spacer, and at the same time, it is also beneficial to improve the assembly stability of the first lens and the second lens.

[0056] In an exemplary embodiment, the radius of curvature R6 of the second side surface of the third lens and the inner diameter d0m of the second side end surface of the barrel may satisfy: -2.0 < R6 / d0m < -1.1. By controlling the ratio of the radius of curvature of the second side surface of the third lens to the inner diameter of the second side end surface of the barrel, the inner diameter of the second side end surface of the barrel can be restricted within a reasonable range, so that the second side end of the barrel has an appropriate opening size, improving the processability of the barrel; at the same time, it can also limit the outer shapes of the lenses and spacers inside the barrel, reducing the processing difficulty of the lenses and spacers, and improving the processability of the lenses and spacers.

[0057] In an exemplary embodiment, the effective focal length f1 of the first lens and the outer diameter D0s of the first side end surface of the barrel may satisfy: 2.7 < f1 / D0s < 3.1. By controlling the ratio of the effective focal length of the first lens to the outer diameter of the first side end surface of the barrel, the shape of the first lens can be reasonably restricted, improving the processability of the first lens; at the same time, in cooperation with restricting the outer diameter of the first side end surface of the barrel, it is beneficial to improve the processability of the barrel while ensuring that the structural strength of the barrel meets the requirements.

[0058] In an exemplary embodiment, the inner diameter d0s of the first side end surface of the barrel and the inner diameter d0m of the second side end surface of the barrel may satisfy: 1.2 < d0m / d0s < 1.6. By controlling the ratio of the inner diameter of the second side end surface to the inner diameter of the first side end surface of the barrel, the opening and trend of the inner wall structure of the barrel can be restricted, so that the barrel has an appropriate opening angle, reducing the processing difficulty of the barrel, and improving the processability of the barrel; at the same time, it can also limit the outer diameter sizes of the lenses and spacers inside the barrel, reducing the processing difficulty of the lenses and spacers, and improving the processability of the lenses and spacers.

[0059] In an exemplary embodiment, the total effective focal length f of the visual system and the outer diameter D0bm of the second side surface of the barrel auxiliary spacer may satisfy: 1.9 < D0bm / f < 2.7. By controlling the ratio of the outer diameter of the second side surface of the barrel auxiliary spacer to the total effective focal length of the visual system, while ensuring that the visual system has a reasonable focal length, the outer diameter of the second side surface of the barrel auxiliary spacer can be constrained within a reasonable range, which is beneficial to improving the machinability of the barrel auxiliary spacer.

[0060] In an exemplary embodiment, the maximum length L of the barrel in the direction of the optical axis, the central thickness CT2 of the second lens on the optical axis, and the central thickness CT3 of the third lens on the optical axis may satisfy: 0.9 < L / (CT2 + CT3) < 1.4. By controlling the above conditional expression, the maximum length of the barrel in the direction of the optical axis can be constrained within a reasonable range to ensure the miniaturization of the visual system; at the same time, in combination with restricting the central thicknesses of the second lens and the third lens, it is beneficial to improving the machinability of the second lens and the third lens.

[0061] In an exemplary embodiment, the entrance pupil diameter EPD of the visual system, the inner diameter d1s of the first side surface of the first spacer, and the inner diameter d0bs of the first side surface of the barrel auxiliary spacer may satisfy: 1.2 < EPD / (d1s - d0bs) < 2.6. By controlling the above conditional expression, the inner diameter of the first side surface of the first spacer and the inner diameter of the first side surface of the barrel auxiliary spacer can be constrained within a reasonable range, which is beneficial to improving the machinability of the first spacer and the barrel auxiliary spacer.

[0062] In an exemplary embodiment, the combined focal length fz of the first lens, the reflective polarizing element, and the quarter-wave plate and the outer diameter D0bs of the first side surface of the barrel auxiliary spacer may satisfy: 2.8 < fz / D0bs < 3.2. By controlling the ratio of the combined focal length of the first lens, the reflective polarizing element, and the quarter-wave plate to the outer diameter of the first side surface of the barrel auxiliary spacer, the combined focal length of the first lens, the reflective polarizing element, and the quarter-wave plate can be constrained to ensure that the light has appropriate incident and exit angles; at the same time, in combination with restricting the outer diameter of the first side surface of the barrel auxiliary spacer, it is beneficial to improving the assembly stability between the barrel auxiliary spacer, the first lens, and the barrel.

[0063] In an exemplary embodiment, the axial distance TD from the first side surface of the first lens to the second side surface of the third lens and the outer diameter D0m of the second side end surface of the barrel may satisfy: 2.9 < D0m / TD < 4.1. By controlling the above conditional expression, the axial distance from the first side surface of the first lens to the second side surface of the third lens can be constrained within a reasonable range to ensure the miniaturization of the visual system; at the same time, in combination with restricting the outer diameter of the second side end surface of the barrel, it is beneficial to improving the machinability of the barrel.

[0064] In an exemplary embodiment, the refractive index N1 of the first lens, the refractive index N2 of the second lens, the outer diameter D1s of the first side surface of the first spacer, and the outer diameter D1m of the second side surface of the first spacer may satisfy: 1.0 < (N2 / N1)×(D1m / D1s) < 1.2. By controlling the above conditional expression, the refractive indices of the first lens and the second lens can be constrained, and further the optical powers of the first lens and the second lens can be limited, so that the entire visual system achieves the best imaging effect and the largest image plane; at the same time, by cooperating with limiting the ratio of the outer diameter of the second side surface to the first side surface of the first spacer, it is beneficial to improve the processability of the first spacer.

[0065] In an exemplary embodiment, the on-axis distance T12 from the second side surface of the first lens to the first side surface of the second lens, the maximum thickness CP1 of the first spacer, and the interval EP12 between the first spacer and the second spacer along the optical axis may satisfy: 4.3 < (CP1 + EP12) / T12 < 8.0. By controlling the above conditional expression, the on-axis distance from the second side surface of the first lens to the first side surface of the second lens can be constrained within a reasonable range, which is beneficial to correcting the field curvature of the entire visual system and ensuring that the optical performance of the visual system meets the requirements; at the same time, by cooperating with limiting the maximum thickness of the first spacer and the interval between the first spacer and the second spacer along the optical axis, the thickness of the first spacer and the edge thickness of the second lens can be reasonably distributed, and the processability of the first spacer and the second lens can be improved.

[0066] In an exemplary embodiment, the effective focal length f3 of the third lens, the inner diameter d2m of the second side surface of the second spacer, and the outer diameter D2m of the second side surface of the second spacer may satisfy: 0.5 < f3 / (d2m + D2m) < 2.7. By controlling the above conditional expression, the effective focal length of the third lens can be constrained within a reasonable range, which is beneficial to optimizing the light path, ensuring that the light path is more reasonable, and improving the imaging quality of the visual system; at the same time, by cooperating with limiting the inner diameter and the outer diameter of the second side surface of the second spacer, it is beneficial to improve the processability of the second spacer while ensuring that the support performance of the second spacer meets the design requirements.

[0067] In an exemplary embodiment, the combined focal length f23 of the second lens and the third lens, the inner diameter d2s of the first side surface of the second spacer, and the outer diameter D2s of the first side surface of the second spacer can satisfy: 0.8<(d2s+D2s) / f23<1.2. By controlling the above conditional expression, the combined focal length of the second lens and the third lens can be limited to a reasonable range, which is conducive to constraining the shapes of the second lens and the third lens, and ensuring that the direction of light is more reasonable, thereby improving the imaging quality of the visual system; at the same time, limiting the inner diameter and outer diameter of the first side surface of the second spacer is conducive to improving the supporting performance of the second spacer, thereby improving the assembly stability between the second spacer and the second lens and the third lens.

[0068] In an exemplary embodiment, the maximum thickness CP0b of the auxiliary spacer of the lens barrel, the maximum thickness CP1 of the first spacer, and the maximum thickness CP2 of the second spacer can satisfy: 1.5<(CP0b+CP1) / CP2<2.1. By controlling the above conditional formula, the thickness of the auxiliary spacer of the lens barrel, the first spacer, and the second spacer can be reasonably allocated. Under the condition of ensuring the machinability and structural strength of the auxiliary spacer of the lens barrel, the first spacer, and the second spacer, the problem of excessive thickness of the entire device caused by excessive thickness of the auxiliary spacer of the lens barrel, the first spacer, and the second spacer, which affects the wearing effect of the entire device, is avoided, thereby improving the wearing experience of the user.

[0069] The visual system according to the above-mentioned embodiment of the present application may use multiple lenses, such as the three lenses described above. By reasonably allocating the parameters of the reflective polarizing element, the quarter-wave plate, each lens, the lens barrel and each spacer, the main body length of the visual system can be reduced, and the processability, assembly stability and imaging quality of the visual system can be improved. The visual system configured as above has the characteristics of miniaturization, large field of view and good imaging quality, which can well meet the use requirements of various portable electronic products in projection scenes, and the center of gravity of the visual system and the device including the visual system is moved backward, which improves the user's wearing experience.

[0070] In an embodiment of the present application, at least one of the surfaces of each lens in the first lens to the third lens is an aspherical surface. The characteristic of an aspherical lens is that the curvature changes continuously from the center of the lens to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has a better curvature radius characteristic, and has the advantages of improving distortion aberration and improving astigmatism aberration. After adopting an aspherical lens, the aberration occurring during imaging can be eliminated as much as possible, thereby improving the imaging quality.

[0071] However, those skilled in the art should understand that, without departing from the technical solutions claimed in this application, the number of lenses constituting the visual system can be changed to obtain the various results and advantages described in this specification.

[0072] The second aspect of this application provides a visual system that may include a lens barrel, and an optical element group and a spacer group disposed within the lens barrel. The optical element group includes a first lens with a positive optical power, a reflective polarizing element, a quarter-wave plate, a second lens with an optical power, and a third lens with a positive optical power arranged in sequence along the optical axis from the first side to the second side; the first side of the first lens is convex, and the second side is flat; the first side of the second lens is convex; the second side of the third lens is convex. The spacer group includes a lens barrel auxiliary spacer, a first spacer, and a second spacer; the lens barrel auxiliary spacer is disposed on and in contact with the first side of the first lens; the first spacer is disposed between the first lens and the second lens; the second spacer is disposed between the second lens and the third lens.

[0073] Wherein, the radius of curvature R1 of the first side of the first lens and the radius of curvature R3 of the first side of the second lens may satisfy: 0.1 < R1 / R3 < 0.6; the maximum thickness CP0b of the lens barrel auxiliary spacer, the maximum thickness CP1 of the first spacer, and the maximum thickness CP2 of the second spacer may satisfy: 1.5 < (CP0b + CP1) / CP2 < 2.1. The visual system provided by this application is configured as a catadioptric optical system with three lenses, effectively shortening the body length of the visual system and avoiding the problems of blurred outer field images and poor imaging quality caused by a visual system having two lenses. When the visual system satisfies "0.1 < R1 / R3 < 0.6", reasonably distributing the thicknesses of the lens barrel auxiliary spacer, the first spacer, and the second spacer can improve the processability and structural strength of the lens barrel auxiliary spacer, the first spacer, and the second spacer, and avoid the problem that the overall thickness of the whole machine is too large due to the excessive thicknesses of the lens barrel auxiliary spacer, the first spacer, and the second spacer, thereby affecting the wearing effect of the whole machine and enhancing the user's wearing experience.

[0074] The following further describes specific embodiments of the visual system applicable to the above embodiments with reference to the accompanying drawings.

[0075] Example 1

[0076] The following refers to Figure 2 Describe the visual system according to Embodiment 1 of this application.

[0077] As Figure 2As shown, the visual system may include a lens barrel P0 and an optical element group and a spacer group placed in the lens barrel P0. The optical element group includes a first lens E1, a reflective polarizing element RP, a quarter wave plate QWP, a second lens E2, and a third lens E3 arranged in sequence from the first side to the second side along the optical axis. A stop STO (not shown) may also be provided between the first side and the first lens E1. A partial reflection layer BS (not shown) may also be provided on the second side of the third lens E3. The spacer group includes a lens barrel auxiliary spacer P0b, a first spacer P1, and a second spacer P2. In the present embodiment, the first side refers to the human eye side, and the second side refers to the display screen side. The first side of each element (the first lens E1, the second lens E2, the third lens E3, the reflective polarizing element RP, and the quarter wave plate QWP) is referred to as the near human eye side, and the second side is referred to as the near screen side.

[0078] The first lens E1 has positive focal power, and its side surface S1 near the human eye is convex, and its side surface S2 near the screen is flat. The reflective polarizer RP has a side surface near the human eye and a side surface near the screen, and the side surface near the human eye of the reflective polarizer RP is attached to the side surface S2 near the screen of the first lens E1. The quarter-wave plate QWP has a side surface near the human eye and a side surface near the screen, and its side surface near the human eye is attached to the side surface near the screen of the reflective polarizer RP. The second lens E2 has positive focal power, and its side surface S3 near the human eye is convex, and its side surface S4 near the screen is convex. The third lens E3 has positive focal power, and its side surface S5 near the human eye is concave, and its side surface S6 near the screen is convex. The partial reflection layer BS can be attached to the side surface S6 near the screen of the third lens E3.

[0079] In this example, an image surface IMG may be provided on the second side of the visual system, and the image surface IMG may be provided with a display screen, for example. After the image light from the image surface IMG passes through the third lens E3, the second lens E2, the quarter-wave plate QWP in sequence and reaches the reflective polarizing element RP located on the near-screen side of the first lens E1, a first reflection occurs at the reflective polarizing element RP. After the light reflected for the first time passes through the quarter-wave plate QWP, the second lens E2, the third lens E3 and reaches the partially reflective layer BS located on the near-screen side of the third lens E3, a second reflection occurs at the partially reflective layer BS. The light reflected for the second time passes through the third lens E3, the second lens E2, the quarter-wave plate QWP, the reflective polarizing element RP, the first lens E1 in sequence and is finally projected onto a target object (not shown) in space. For example, the light of the visual system after two reflections is finally projected into the eyes of the user.

[0080] Table 1 shows the basic parameters of the visual system of Example 1, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm). The image light from the image surface IMG passes through the components in the order of sequence number 19 to sequence number 1 and is finally projected into the human eye.

[0081]

[0082]

[0083] Table 1

[0084] In this embodiment, the first side surface S1 of the first lens E1, the first side surface S3 and the second side surface S4 of the second lens E2, and the first side surface S5 and the second side surface S6 of the third lens E3 are all aspherical surfaces, and the surface shape x of each aspherical lens can be defined by but not limited to the following aspherical surface formula:

[0085]

[0086] Wherein, x is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c=1 / R (i.e., the paraxial curvature c is the reciprocal of the curvature radius R in Table 1 above); k is the cone coefficient; Ai is the correction coefficient of the i-th order of the aspheric surface. Table 2 shows the high-order coefficients A that can be used for each aspheric surface S1, S3-S6 in Example 1 4 , A 6 , A 8 , A 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0087] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 1.7237E+00 -1.0531E-02 1.8280E-02 1.1790E-02 1.9481E-03 -2.2963E-03 4.9674E-04 0.0000E+00 0.0000E+00 S3 -1.7897E-01 -4.5955E-02 3.6542E-02 -2.4898E-03 -5.2026E-03 4.4163E-03 -1.1827E-03 0.0000E+00 0.0000E+00 S4 -2.0077E-01 -2.0784E-01 -3.5027E-02 3.7970E-03 1.8428E-02 1.3874E-02 -7.2088E-04 0.0000E+00 0.0000E+00 S5 -1.7781E+00 -4.2544E-01 -1.1943E-01 -2.8744E-02 5.6071E-03 9.3229E-03 1.8844E-03 0.0000E+00 0.0000E+00 S6 -1.0784E-01 -6.9805E-02 -8.2343E-03 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0088] Table 2

[0089] Example 2

[0090] The following reference Figure 3 Describe the visual system according to Example 2 of the present application.

[0091] like Figure 3As shown, the visual system can include a lens barrel P0 and an optical element group and a spacer group placed in the lens barrel P0. The optical element group includes a first lens E1, a reflective polarizing element RP, a quarter wave plate QWP, a second lens E2 and a third lens E3 arranged in sequence from the first side to the second side along the optical axis. A stop STO (not shown) can also be provided between the first side and the first lens E1. The second side of the third lens E3 can also be provided with a partial reflection layer BS (not shown). The spacer group includes a lens barrel auxiliary spacer P0b, a first spacer P1 and a second spacer P2.

[0092] The structure of the optical element group of this embodiment is the same as that of the optical element group of embodiment 1, that is, the basic parameter table of the visual system of this embodiment is the same as Table 1, and the aspheric coefficient table is the same as Table 2. The difference between this embodiment and embodiment 1 is that the structural dimensions of the lens barrel P0, the lens barrel auxiliary spacer P0b, the first spacer P1, and the second spacer P2 are different. For example, the parameters such as d1s, d1m, D1s, D1m, d2s, d2m, D2s, D2m, d0s, d0m, D0s, D0m, d0bs, d0bm, D0bs, D0bm, CP0b, CP1, EP12, CP2 and L are different.

[0093] Example 3

[0094] The following reference Figure 4 Describe the visual system according to Example 3 of the present application.

[0095] like Figure 4 As shown, the visual system can include a lens barrel P0 and an optical element group and a spacer group placed in the lens barrel P0. The optical element group includes a first lens E1, a reflective polarizing element RP, a quarter wave plate QWP, a second lens E2 and a third lens E3 arranged in sequence from the first side to the second side along the optical axis. A stop STO (not shown) can also be provided between the first side and the first lens E1. The second side of the third lens E3 can also be provided with a partial reflection layer BS (not shown). The spacer group includes a lens barrel auxiliary spacer P0b, a first spacer P1 and a second spacer P2.

[0096] The structure of the optical element group of this embodiment is the same as that of the optical element group of embodiment 1, that is, the basic parameter table of the visual system of this embodiment is the same as Table 1, and the aspheric coefficient table is the same as Table 2. The difference between this embodiment and embodiment 1 is that the structural dimensions of the lens barrel P0, the lens barrel auxiliary spacer P0b, the first spacer P1, and the second spacer P2 are different. For example, the parameters such as d1s, d1m, D1s, D1m, d2s, d2m, D2s, D2m, d0s, d0m, D0s, D0m, d0bs, d0bm, D0bs, D0bm, CP0b, CP1, EP12, CP2 and L are different.

[0097] Example 4

[0098] The following reference Figure 5 Describe the visual system according to Example 4 of the present application.

[0099] like Figure 5 As shown, the visual system can include a lens barrel P0 and an optical element group and a spacer group placed in the lens barrel P0. The optical element group includes a first lens E1, a reflective polarizing element RP, a quarter wave plate QWP, a second lens E2 and a third lens E3 arranged in sequence from the first side to the second side along the optical axis. A stop STO (not shown) can also be provided between the first side and the first lens E1. The second side of the third lens E3 can also be provided with a partial reflection layer BS (not shown). The spacer group includes a lens barrel auxiliary spacer P0b, a first spacer P1 and a second spacer P2.

[0100] The structure of the optical element group of this embodiment is the same as that of the optical element group of embodiment 1, that is, the basic parameter table of the visual system of this embodiment is the same as Table 1, and the aspheric coefficient table is the same as Table 2. The difference between this embodiment and embodiment 1 is that the structural dimensions of the lens barrel P0, the lens barrel auxiliary spacer P0b, the first spacer P1, and the second spacer P2 are different. For example, the parameters such as d1s, d1m, D1s, D1m, d2s, d2m, D2s, D2m, d0s, d0m, D0s, D0m, d0bs, d0bm, D0bs, D0bm, CP0b, CP1, EP12, CP2 and L are different.

[0101] Fig. 6A The axial chromatic aberration curves of the visual systems of Examples 1, 2, 3, and 4 are shown, which indicate the deviation of the focal point of light of different wavelengths after passing through the visual system. Figure 6B Astigmatism curves of the visual systems of Examples 1, 2, 3, and 4 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field angles. Figure 6C The distortion curves of the visual systems of Examples 1, 2, 3, and 4 are shown, which represent the distortion values ​​corresponding to different field angles. FIG. 6A to FIG. 6C It can be seen that the visual systems provided in Examples 1, 2, 3, and 4 can achieve good imaging quality.

[0102] Example 5

[0103] The following reference Figure 7 Describe the visual system according to Example 5 of the present application.

[0104] like Figure 7As shown, the visual system may include a lens barrel P0 and an optical element group and a spacer group placed in the lens barrel P0. The optical element group includes a first lens E1, a reflective polarizing element RP, a quarter wave plate QWP, a second lens E2, and a third lens E3 arranged in sequence from the first side to the second side along the optical axis. A stop STO (not shown) may also be provided between the first side and the first lens E1. A partial reflection layer BS (not shown) may also be provided on the second side of the third lens E3. The spacer group includes a lens barrel auxiliary spacer P0b, a first spacer P1, and a second spacer P2. In the present embodiment, the first side refers to the human eye side, and the second side refers to the display screen side. The first side of each element (the first lens E1, the second lens E2, the third lens E3, the reflective polarizing element RP, and the quarter wave plate QWP) is referred to as the near human eye side, and the second side is referred to as the near screen side.

[0105] The first lens E1 has positive focal power, and its side surface S1 near the human eye is convex, and its side surface S2 near the screen is flat. The reflective polarizer RP has a side surface near the human eye and a side surface near the screen, and the side surface near the human eye of the reflective polarizer RP is attached to the side surface S2 near the screen of the first lens E1. The quarter-wave plate QWP has a side surface near the human eye and a side surface near the screen, and its side surface near the human eye is attached to the side surface near the screen of the reflective polarizer RP. The second lens E2 has negative focal power, and its side surface S3 near the human eye is convex, and its side surface S4 near the screen is concave. The third lens E3 has positive focal power, and its side surface S5 near the human eye is convex, and its side surface S6 near the screen is convex. The partial reflection layer BS can be attached to the side surface S6 near the screen of the third lens E3.

[0106] In this example, an image surface IMG may be provided on the second side of the visual system, and the image surface IMG may be provided with a display screen, for example. After the image light from the image surface IMG passes through the third lens E3, the second lens E2, the quarter-wave plate QWP in sequence and reaches the reflective polarizing element RP located on the near-screen side of the first lens E1, a first reflection occurs at the reflective polarizing element RP. After the light reflected for the first time passes through the quarter-wave plate QWP, the second lens E2, the third lens E3 and reaches the partially reflective layer BS located on the near-screen side of the third lens E3, a second reflection occurs at the partially reflective layer BS. The light reflected for the second time passes through the third lens E3, the second lens E2, the quarter-wave plate QWP, the reflective polarizing element RP, the first lens E1 in sequence and is finally projected onto a target object (not shown) in space. For example, the light of the visual system after two reflections is finally projected into the eyes of the user.

[0107] Table 3 shows the basic parameters of the visual system of Example 5, wherein the units of the radius of curvature and thickness / distance are all millimeters (mm). The image light from the image surface IMG passes through the components in the order of sequence number 19 to sequence number 1 and is finally projected into the human eye.

[0108]

[0109]

[0110] Table 3

[0111] In this embodiment, the first side surface S1 of the first lens E1, the first side surface S3 and the second side surface S4 of the second lens E2, and the first side surface S5 and the second side surface S6 of the third lens E3 are all aspherical surfaces. Table 4 lists the high-order coefficients A of the aspherical surfaces S1, S3-S6 that can be used in Embodiment 5. 4 , A 6 , A 8 , A 10 , A 12 , A 14 , A 16 , A 18 and A 20 .

[0112] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 -6.1153E-01 -3.3166E-01 8.0580E-03 -1.1441E-02 -2.5244E-03 8.2930E-03 1.6853E-03 0.0000E+00 0.0000E+00 S3 -6.0641E-01 2.6268E-01 -7.4653E-02 8.7985E-02 -2.9213E-02 1.9815E-03 -7.5513E-04 0.0000E+00 0.0000E+00 S4 -1.0827E+00 -2.2629E-01 -5.0583E-02 5.2634E-02 -2.9721E-02 1.0318E-02 5.9363E-04 0.0000E+00 0.0000E+00 S5 -1.6093E+00 -1.2201E-01 1.8394E-02 -3.2984E-02 1.2357E-02 -1.0253E-02 1.6463E-03 0.0000E+00 0.0000E+00 S6 4.2211E-03 -1.3171E-02 -1.4171E-03 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0113] Table 4

[0114] Example 6

[0115] The following reference Figure 8 Describe the visual system according to Example 6 of the present application.

[0116] like Figure 8 As shown, the visual system can include a lens barrel P0 and an optical element group and a spacer group placed in the lens barrel P0. The optical element group includes a first lens E1, a reflective polarizing element RP, a quarter wave plate QWP, a second lens E2 and a third lens E3 arranged in sequence from the first side to the second side along the optical axis. A stop STO (not shown) can also be provided between the first side and the first lens E1. The second side of the third lens E3 can also be provided with a partial reflection layer BS (not shown). The spacer group includes a lens barrel auxiliary spacer P0b, a first spacer P1 and a second spacer P2.

[0117] The structure of the optical element group of this embodiment is the same as that of the optical element group of embodiment 5, that is, the basic parameter table of the visual system of this embodiment is the same as Table 3, and the aspheric coefficient table is the same as Table 4. The difference between this embodiment and embodiment 5 is that the structural dimensions of the lens barrel P0, the lens barrel auxiliary spacer P0b, the first spacer P1, and the second spacer P2 are different. For example, the parameters such as d1s, d1m, D1s, D1m, d2s, d2m, D2s, D2m, d0s, d0m, D0s, D0m, d0bs, d0bm, D0bs, D0bm, CP0b, CP1, EP12, CP2 and L are different.

[0118] Fig.9A The axial chromatic aberration curves of the visual systems of Examples 5 and 6 are shown, which indicate the deviation of the focal point of light of different wavelengths after passing through the visual system. Fig. 9B The astigmatism curves of the visual systems of Examples 5 and 6 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field angles. Fig. 9C The distortion curves of the visual systems of Examples 5 and 6 are shown, which represent the distortion values ​​corresponding to different field angles. 9A to 9C It can be seen that the visual systems provided in Examples 5 and 6 can achieve good imaging quality.

[0119] Example 7

[0120] The following reference Fig.10 Describe the visual system according to Example 7 of the present application.

[0121] like Fig.10 As shown, the visual system may include a lens barrel P0 and an optical element group and a spacer group placed in the lens barrel P0. The optical element group includes a first lens E1, a reflective polarizing element RP, a quarter wave plate QWP, a second lens E2, and a third lens E3 arranged in sequence from the first side to the second side along the optical axis. A stop STO (not shown) may also be provided between the first side and the first lens E1. A partial reflection layer BS (not shown) may also be provided on the second side of the third lens E3. The spacer group includes a lens barrel auxiliary spacer P0b, a first spacer P1, and a second spacer P2. In the present embodiment, the first side refers to the human eye side, and the second side refers to the display screen side. The first side of each element (the first lens E1, the second lens E2, the third lens E3, the reflective polarizing element RP, and the quarter wave plate QWP) is referred to as the near human eye side, and the second side is referred to as the near screen side.

[0122] The first lens E1 has positive focal power, and its side surface S1 near the human eye is convex, and its side surface S2 near the screen is flat. The reflective polarizer RP has a side surface near the human eye and a side surface near the screen, and the side surface near the human eye of the reflective polarizer RP is attached to the side surface S2 near the screen of the first lens E1. The quarter-wave plate QWP has a side surface near the human eye and a side surface near the screen, and its side surface near the human eye is attached to the side surface near the screen of the reflective polarizer RP. The second lens E2 has positive focal power, and its side surface S3 near the human eye is convex, and its side surface S4 near the screen is concave. The third lens E3 has positive focal power, and its side surface S5 near the human eye is convex, and its side surface S6 near the screen is convex. The partial reflection layer BS can be attached to the side surface S6 near the screen of the third lens E3.

[0123] In this example, an image surface IMG may be provided on the second side of the visual system, and the image surface IMG may be provided with a display screen, for example. After the image light from the image surface IMG passes through the third lens E3, the second lens E2, the quarter-wave plate QWP in sequence and reaches the reflective polarizing element RP located on the near-screen side of the first lens E1, a first reflection occurs at the reflective polarizing element RP. After the light reflected for the first time passes through the quarter-wave plate QWP, the second lens E2, the third lens E3 and reaches the partially reflective layer BS located on the near-screen side of the third lens E3, a second reflection occurs at the partially reflective layer BS. The light reflected for the second time passes through the third lens E3, the second lens E2, the quarter-wave plate QWP, the reflective polarizing element RP, the first lens E1 in sequence and is finally projected onto a target object (not shown) in space. For example, the light of the visual system after two reflections is finally projected into the eyes of the user.

[0124] Table 5 shows the basic parameters of the visual system of Example 7, where the units of the radius of curvature and thickness / distance are all in millimeters (mm). The image light from the image surface IMG passes through each element in the order of sequence number 19 to sequence number 1 and is finally projected into the human eye.

[0125]

[0126]

[0127] Table 5

[0128] In this embodiment, the first side surface S1 of the first lens E1, the first side surface S3 and the second side surface S4 of the second lens E2, and the first side surface S5 and the second side surface S6 of the third lens E3 are all aspherical surfaces. Table 6 lists the high-order coefficients A of the aspherical surfaces S1, S3-S6 that can be used in Embodiment 7. 4 , A 6 , A 8 , A 10 , A 12 , A14 , A 16 , A 18 and A 20 .

[0129] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 -7.7832E-02 -8.0278E-02 -4.4280E-02 1.4286E-02 -4.7680E-03 -5.9445E-04 -3.2749E-04 0.0000E+00 0.0000E+00 S3 -5.2647E-01 1.7378E-02 1.4687E-03 -5.6363E-04 -5.7278E-03 -2.4342E-03 4.0963E-04 0.0000E+00 0.0000E+00 S4 -2.6318E-01 1.4742E-01 -2.4382E-01 4.3098E-02 -4.1613E-03 -1.4102E-02 3.0397E-03 0.0000E+00 0.0000E+00 S5 -6.2284E-01 1.6363E-01 -1.1425E-01 1.3515E-02 6.2756E-03 -5.2626E-03 1.3959E-03 0.0000E+00 0.0000E+00 S6 6.3214E-03 -1.1485E-02 -1.2245E-03 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0130] Table 6

[0131] Example 8

[0132] The following reference Fig.11 Describe the visual system according to Example 8 of the present application.

[0133] like Fig.11 As shown, the visual system can include a lens barrel P0 and an optical element group and a spacer group placed in the lens barrel P0. The optical element group includes a first lens E1, a reflective polarizing element RP, a quarter wave plate QWP, a second lens E2 and a third lens E3 arranged in sequence from the first side to the second side along the optical axis. A stop STO (not shown) can also be provided between the first side and the first lens E1. The second side of the third lens E3 can also be provided with a partial reflection layer BS (not shown). The spacer group includes a lens barrel auxiliary spacer P0b, a first spacer P1 and a second spacer P2.

[0134] The structure of the optical element group of this embodiment is the same as that of the optical element group of embodiment 7, that is, the basic parameter table of the visual system of this embodiment is the same as Table 5, and the aspheric coefficient table is the same as Table 6. The difference between this embodiment and embodiment 7 is that the structure dimensions of the lens barrel P0, the lens barrel auxiliary spacer P0b, the first spacer P1, and the second spacer P2 are different. For example, the parameters such as d1s, d1m, D1s, D1m, d2s, d2m, D2s, D2m, d0s, d0m, D0s, D0m, d0bs, d0bm, D0bs, D0bm, CP0b, CP1, EP12, CP2, and L are different.

[0135] Fig. 12A The axial chromatic aberration curves of the visual systems of Examples 7 and 8 are shown, which indicate the deviation of the focal point of light of different wavelengths after passing through the visual system. Fig. 12B The astigmatism curves of the visual systems of Examples 7 and 8 are shown, which represent the meridional image plane curvature and sagittal image plane curvature corresponding to different field angles. Fig. 12C The distortion curves of the visual systems of Examples 7 and 8 are shown, which represent the distortion values ​​corresponding to different field angles. FIG. 12A to FIG. 12C It can be seen that the visual systems provided in Examples 7 and 8 can achieve good imaging quality.

[0136] Table 7 shows the values ​​of parameters such as fz, f23, f1, f2, f3, EPD, f, TD, etc. of each embodiment in embodiments 1 to 8. The units of the parameters listed in Table 7 are all millimeters (mm).

[0137] Parameters / Examples 1 2 3 4 5 6 7 8 fz 172.57 172.57 172.57 172.57 113.80 113.80 121.98 121.98 f23 109.59 109.59 109.59 109.59 109.20 109.20 77.77 77.77 f1 172.57 172.57 172.57 172.57 113.80 113.80 121.98 121.98 f2 170.50 170.50 170.50 170.50 -82.65 -82.65 3289.20 3289.20 f3 292.23 292.23 292.23 292.23 48.66 48.66 79.22 79.22 EPD 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 f 28.26 28.26 28.26 28.26 15.66 15.66 15.99 15.99 TD 20.85 20.85 20.85 20.85 13.15 13.15 13.57 13.57

[0138] Table 7

[0139] Table 8 gives the values ​​of parameters such as d1s, d1m, D1s, D1m, d2s, d2m, D2s, D2m, d0s, d0m, D0s, D0m, d0bs, d0bm, D0bs, D0bm, CP0b, CP1, EP12, CP2 and L in each embodiment of embodiments 1-8. The above parameters can be calculated according to Figure 1 The parameters listed in Table 8 are measured using the marking method shown in the figure, and the units of the parameters listed in Table 8 are all millimeters (mm).

[0140] Parameters / Examples 1 2 3 4 5 6 7 8 d1s 51.7788 51.6338 51.6330 51.4288 39.5308 39.7954 39.7466 39.9790 d1m 52.2948 52.3719 52.4112 52.0144 39.5308 39.7954 41.0506 40.8405 D1s 54.9269 54.7075 54.6551 54.8093 47.9772 47.7772 43.1709 43.2469 D1m 56.0214 55.7393 55.5540 55.5997 47.9772 47.7772 44.3585 44.0147 d2s 52.6895 52.8098 53.1192 52.7418 43.6115 43.4771 44.1628 44.2094 d2m 53.7105 53.8050 53.5170 53.8886 43.6115 43.4771 44.5656 44.6111 D2s 57.1681 57.0151 57.2920 57.0920 49.9621 49.7621 47.0923 47.0888 D2m 58.0858 57.9685 58.0275 57.8275 49.9621 49.7621 47.6141 47.4588 d0s 47.6128 47.7329 48.0435 47.5393 33.9614 34.2051 35.5344 35.5344 d0m 60.3725 60.4188 60.2874 60.4955 51.1808 51.2607 50.2423 50.4403 D0s 56.8924 56.5669 57.4582 56.3170 42.0614 41.8113 44.9250 44.9250 D0m 62.5725 62.5330 62.6577 62.4457 53.3808 53.2831 52.6032 52.6205 d0bs 49.4475 49.5811 49.6443 49.4081 35.7961 35.6946 37.5530 37.3078 d0bm 49.4475 49.5811 49.6443 49.4081 35.7961 35.6946 37.5530 37.3078 D0bs 54.9560 54.6560 54.6560 54.6560 39.7815 39.7815 42.9814 42.9814 D0bm 54.9560 54.6560 54.6560 54.6560 39.7815 39.7815 42.9814 42.9814 CP0b 0.1000 0.1000 0.1000 0.1000 0.1000 0.1000 0.1000 0.1000 CP1 2.3901 2.3901 2.3901 2.2901 0.1000 0.1000 1.2180 1.2180 EP12 3.1391 3.1391 3.1391 3.1302 3.8589 3.8589 1.8305 1.8305 CP2 1.3707 1.3707 1.4796 1.4796 0.1000 0.1000 0.8378 0.8378 L 14.2326 14.0326 14.0326 14.0326 9.7312 9.5812 9.3946 9.4946

[0141] Table 8 In summary, Table 9 shows the values ​​of the conditional expressions of each embodiment in Embodiments 1 to 8.

[0142]

[0143]

[0144] Table 9

[0145] The present application also provides an optical device, which may be an independent projection device such as a projector, or a projection module integrated in a mobile electronic device such as a virtual reality device. The optical device is equipped with the visual system described above.

[0146] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the utility model involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features with similar functions disclosed in the present application (but not limited to) by each other.

Claims

1. A visual system, characterized in that: include: An optical element group, comprising a first lens with positive optical power, a reflective polarizing element, a quarter wave plate, a second lens with optical power, and a third lens with positive optical power, which are arranged in sequence from a first side to a second side along an optical axis; a first side surface of the first lens is a convex surface, and a second side surface is a plane surface; a first side surface of the second lens is a convex surface; and a second side surface of the third lens is a convex surface; a spacer group, comprising a barrel auxiliary spacer disposed on a first side surface of the first lens and in contact with the first side surface of the first lens, and a first spacer disposed between the first lens and the second lens; A lens barrel, wherein the optical element group and the spacer group are placed in the lens barrel; The curvature radius R1 of the first side surface of the first lens and the curvature radius R3 of the first side surface of the second lens satisfy: 0.1 <R1 / R3<0.6; as well as The inner diameter d0bm of the second side surface of the lens barrel auxiliary spacer and the inner diameter d1m of the second side surface of the first spacer satisfy: 1.0 <d1m / d0bm<1.2。 2. The visual system according to claim 1, characterized in that: The curvature radius R6 of the second side surface of the third lens and the inner diameter d0m of the second side end surface of the lens barrel satisfy: -2.0 <R6 / d0m<-1.1。 3. The visual system according to claim 1, characterized in that: The effective focal length f1 of the first lens and the outer diameter D0s of the first side end surface of the lens barrel satisfy: 2.7 <f1 / D0s<3.1。 4. The visual system according to claim 1, characterized in that: The inner diameter d0s of the first side end surface of the lens barrel and the inner diameter d0m of the second side end surface of the lens barrel satisfy: 1.2 <d0m / d0s<1.6。 5. The visual system according to claim 1, characterized in that: The total effective focal length f of the visual system and the outer diameter D0bm of the second side of the auxiliary spacer of the lens barrel satisfy: 1.9 <D0bm / f<2.7。 6. The visual system according to claim 1, characterized in that: The maximum length L of the lens barrel along the direction of the optical axis, the center thickness CT2 of the second lens on the optical axis, and the center thickness CT3 of the third lens on the optical axis satisfy: 0.9 <L / (CT2+CT3)<1.4。 7. The visual system according to claim 1, characterized in that: The entrance pupil diameter EPD of the visual system, the inner diameter d1s of the first side of the first spacer and the inner diameter d0bs of the first side of the lens barrel auxiliary spacer satisfy: 1.2 <EPD / (d1s-d0bs)<2.6。 8. The visual system according to claim 1, characterized in that: The combined focal length fz of the first lens, the reflective polarizing element and the quarter-wave plate and the outer diameter D0bs of the first side surface of the lens barrel auxiliary spacer satisfy: 2.8 <fz / D0bs<3.2。 9. The visual system according to claim 1, characterized in that: The axial distance TD from the first side surface of the first lens to the second side surface of the third lens and the outer diameter D0m of the second side end surface of the lens barrel satisfy: 2.9 <D0m / TD<4.1。 10. The visual system according to claim 1, characterized in that: The refractive index N1 of the first lens, the refractive index N2 of the second lens, the outer diameter D1s of the first side surface of the first spacer, and the outer diameter D1m of the second side surface of the first spacer satisfy: 1.0<(N2 / N1)×(D1m / D1s)<1.

2.

11. The visual system according to any one of claims 1 to 10, characterized in that: The spacer set further includes a second spacer disposed between the second lens and the third lens; Among them, the on-axis distance T12 from the second side surface of the first lens to the first side surface of the second lens, the maximum thickness CP1 of the first spacer, and the interval EP12 between the first spacer and the second spacer along the optical axis satisfy: 4.3<(CP1+EP12) / T12<8.

0.

12. The visual system according to any one of claims 1 to 10, characterized in that: The spacer set further includes a second spacer disposed between the second lens and the third lens; The effective focal length f3 of the third lens, the inner diameter d2m of the second side surface of the second spacer, and the outer diameter D2m of the second side surface of the second spacer satisfy: 0.5 <f3 / (d2m+D2m)<2.7。 13. The visual system according to any one of claims 1 to 10, characterized in that: The spacer set further includes a second spacer disposed between the second lens and the third lens; The combined focal length f23 of the second lens and the third lens, the inner diameter d2s of the first side surface of the second spacer, and the outer diameter D2s of the first side surface of the second spacer satisfy: 0.8<(d2s+D2s) / f23<1.

2.

14. The visual system according to any one of claims 1 to 10, characterized in that: The spacer set further includes a second spacer disposed between the second lens and the third lens; The maximum thickness CP0b of the lens barrel auxiliary spacer, the maximum thickness CP1 of the first spacer, and the maximum thickness CP2 of the second spacer satisfy: 1.5<(CP0b+CP1) / CP2<2.1.

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