Visual system

Abstract

The utility model provides a visual system. The visual system comprises an optical element group and a lens barrel assembly, the optical element group sequentially comprises a first lens with positive focal power, a reflective polarization element, a quarter-wave plate, a second lens with positive focal power, a partial reflection element and a third lens with positive focal power from the first side to the second side along the optical axis; the lens cone assembly comprises a first lens cone, a second lens cone and a third lens cone; the position of the first lens on the optical axis relative to the image surface of the second side is fixed, and the distance of the second lens on the optical axis relative to the first lens is adjustable; the visual system satisfies the following conditions: 1.0 lt; f2 / (dbs + dbm) lt; 1.3, 2.8 lt, 1.3, 2.8 lt; lc / [delta] Llt; f2 is the effective focal length of the second lens, dbs is the inner diameter of the end face of the first side of the second lens barrel, dbm is the inner diameter of the end face of the second side of the second lens barrel, Lac is the distance between the end face of the second side of the first lens barrel and the end face of the first side of the third lens barrel along the optical axis, and dbm is the inner diameter of the end face of the second side of the second lens barrel. Delta L is the movable distance of the second lens when the visual system is switched between the first state and the second state.

Description

Technical Field

[0001] The present disclosure relates to the field of optical devices, specifically to a visual system. Background Art

[0002] With the development of science and technology, virtual reality devices and / or augmented reality devices are widely used in fields such as gaming, education, medical treatment, and engineering. The visual systems of virtual reality devices and / or augmented reality devices usually adopt Fresnel lenses. The overall length of such visual systems using Fresnel lenses is relatively large, and the volume and weight are relatively large, which affects the user experience. Moreover, such visual systems using Fresnel lenses do not have the function of diopter adjustment and cannot meet the usage requirements of users with different diopters. Utility Model Content

[0003] On the one hand, the present disclosure provides such a visual system, which includes an optical element group and a lens barrel assembly. The optical element group sequentially includes a first lens with positive optical power, a reflective polarizing element, a quarter-wave plate, a second lens with positive optical power, a partial reflection element, and a third lens with positive optical power 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, and the second side is convex. The second side of the third lens is convex. The lens barrel assembly includes a first lens barrel, a second lens barrel, and a third lens barrel. The first lens is placed in the first lens barrel, the second lens is placed in the second lens barrel, and the third lens is placed in the third lens barrel. Among them, the position of the first lens on the optical axis relative to the image plane on the second side is fixed, and the distance of the second lens on the optical axis relative to the first lens is adjustable. The number of lenses with optical power in the visual system is three. The visual system satisfies: 1.0 < f2 / (dbs + dbm) < 1.3, 2.8 < Lac / ΔL < 3.6, where f2 is the effective focal length of the second lens, dbs is the inner diameter of the first side end face of the second lens barrel, dbm is the inner diameter of the second side end face of the second lens barrel, Lac is the distance along the optical axis between the second side end face of the first lens barrel and the first side end face of the third lens barrel, and ΔL is the movable distance of the second lens when the visual system switches between the first state and the second state.

[0004] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 3.90 ≤ (Das - das) / La ≤ 5.74, where das is the inner diameter of the first side end face of the first lens barrel, Das is the outer diameter of the first side end face of the first lens barrel, and La is the distance along the optical axis between the first side end face of the first lens barrel and the second side end face of the first lens barrel.

[0005] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 1.29 ≤ fg / (dam + Dam) ≤ 1.55, where fg is the combined focal length of the first lens, the reflective polarizing element, and the quarter-wave plate, dam is the inner diameter of the second side end face of the first barrel, and Dam is the outer diameter of the second side end face of the first barrel.

[0006] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 1.45 ≤ (CT1 + CTR + CTQ) / La ≤ 1.81, where CT1 is the central thickness of the first lens on the optical axis, CTR is the central thickness of the reflective polarizing element on the optical axis, CTQ is the central thickness of the quarter-wave plate on the optical axis, and La is the distance along the optical axis between the first side end face and the second side end face of the first barrel.

[0007] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 3.45 < CT2 / |Dbs - Dbm| < 5.0, where CT2 is the central thickness of the second lens on the optical axis, Dbs is the outer diameter of the first side end face of the second barrel, and Dbm is the outer diameter of the second side end face of the second barrel.

[0008] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 1.85 < R1 / das < 2.25, where R1 is the radius of curvature of the first side face of the first lens, and das is the inner diameter of the first side end face of the first barrel.

[0009] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 8.25 < dcs / CT3 < 12.55, where dcs is the inner diameter of the first side end face of the third barrel, and CT3 is the central thickness of the third lens on the optical axis.

[0010] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 2.9 < Lb / Δf < 3.85, where Lb is the distance along the optical axis between the first side end face and the second side end face of the second barrel, and Δf is the difference between the total effective focal length of the visual system in the first state and the total effective focal length of the visual system in the second state.

[0011] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 2.5 < f1 / Das < 3.1, where f1 is the effective focal length of the first lens, and Das is the outer diameter of the first side end face of the first barrel. [[ID={19}]]

[0012] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 1.1 < Lc / |Dcs - Dcm| < 2.5, where Lc is the distance along the optical axis between the first side end face and the second side end face of the third lens barrel, Dcs is the outer diameter of the first side end face of the third lens barrel, and Dcm is the outer diameter of the second side end face of the third lens barrel.

[0013] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: -1.55 < R4 / dbm < -1.15, where R4 is the radius of curvature of the second side face of the second lens, and dbm is the inner diameter of the second side end face of the second lens barrel.

[0014] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 1.65 ≤ f3 / (dcm + Dcm) ≤ 3.09, where f3 is the effective focal length of the third lens, dcm is the inner diameter of the second side end face of the third lens barrel, and Dcm is the outer diameter of the second side end face of the third lens barrel.

[0015] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 2.15 < TD / Lac < 2.5, where TD is the on-axis distance from the first side face of the first lens to the second side face of the third lens, and Lac is the distance along the optical axis between the second side end face of the first lens barrel and the first side end face of the third lens barrel.

[0016] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 1.45 < (La + Lc) / Lb < 2.9, where La is the distance along the optical axis between the first side end face and the second side end face of the first lens barrel, Lb is the distance along the optical axis between the first side end face and the second side end face of the second lens barrel, and Lc is the distance along the optical axis between the first side end face and the second side end face of the third lens barrel.

[0017] According to an exemplary embodiment of the present disclosure, the visual system further satisfies: 1.55 ≤ (Das + Dcs) / Dbs ≤ 1.89, where Das is the outer diameter of the first side end face of the first lens barrel, Dbs is the outer diameter of the first side end face of the second lens barrel, and Dcs is the outer diameter of the first side end face of the third lens barrel.

[0018] The visual system provided by the present disclosure can achieve the folding and reflection of the optical path by using a reflective polarizing element, a quarter-wave plate, and a partial reflection element, and can achieve the diopter adjustment of the visual system by moving the second lens. At the same time, by restricting f2 / (dbs + dbm) and Lac / ΔL within reasonable ranges respectively, the visual system can be switched between the first state and the second state, so as to adapt to the different requirements of users such as different diopters, different viewing distances, and different application scenarios, and is also beneficial to reducing problems such as glare and ghosting, and improving the imaging quality of the visual system in different states. Attached Figure Description

[0019] Other features, objects, and advantages of this disclosure will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Wherein:

[0020] Figure 1 A structural layout and parameter diagram of a visual system according to an exemplary embodiment of the present disclosure are shown;

[0021] Figure 2 A schematic diagram of the visual system in its first state according to Embodiment 1 of this disclosure is shown;

[0022] Figure 3 A schematic diagram of the structure of the visual system in the second state according to Embodiment 1 of this disclosure is shown;

[0023] Figure 4 A schematic diagram of the visual system in its first state according to Embodiment 2 of this disclosure is shown;

[0024] Figure 5 A schematic diagram of the visual system in its second state according to Embodiment 2 of this disclosure is shown;

[0025] Figure 6 A schematic diagram of the visual system in its first state according to Embodiment 3 of this disclosure is shown;

[0026] Figure 7 A schematic diagram of the visual system in its second state according to Embodiment 3 of this disclosure is shown;

[0027] Figure 8 The modulation transfer function curves of the visual system in the first state according to Embodiments 1, 2 and 3 of this disclosure are shown;

[0028] Figure 9 The modulation transfer function curves of the visual system in the second state according to Embodiments 1, 2 and 3 of this disclosure are shown;

[0029] Figure 10 A schematic diagram of the structure of the visual system in the first state according to Embodiment 4 of this disclosure is shown;

[0030] Figure 11 A schematic diagram of the visual system in its second state according to Embodiment 4 of this disclosure is shown;

[0031] Figure 12 A schematic diagram of the structure of the visual system in the first state according to Embodiment 5 of this disclosure is shown;

[0032] Figure 13 A schematic diagram of the structure of the visual system in the second state according to Embodiment 5 of this disclosure is shown;

[0033] Figure 14 A schematic diagram of the structure of the visual system in the first state according to Embodiment 6 of this disclosure is shown;

[0034] Figure 15 A schematic diagram of the structure of the visual system in the second state according to Embodiment 6 of this disclosure is shown;

[0035] Figure 16 The modulation transfer function curves of the visual system in the first state according to Embodiments 4, 5 and 6 of this disclosure are shown;

[0036] Figure 17 The modulation transfer function curves of the visual system in the second state according to Embodiments 4, 5 and 6 of this disclosure are shown;

[0037] Figure 18 A schematic diagram of the structure of the visual system in the first state according to Embodiment 7 of this disclosure is shown;

[0038] Figure 19 A schematic diagram of the visual system in its second state according to Embodiment 7 of this disclosure is shown;

[0039] Figure 20 A schematic diagram of the structure of the visual system in the first state according to Embodiment 8 of this disclosure is shown;

[0040] Figure 21 A schematic diagram of the structure of the visual system in the second state according to Embodiment 8 of this disclosure is shown;

[0041] Figure 22 A schematic diagram of the structure of the visual system in the first state according to Embodiment 9 of this disclosure is shown;

[0042] Figure 23 A schematic diagram of the visual system in its second state according to Embodiment 9 of this disclosure is shown;

[0043] Figure 24 The modulation transfer function curves of the visual system in the first state according to Embodiments 7, 8 and 9 of this disclosure are shown;

[0044] Figure 25 The modulation transfer function curves of the visual system in the second state according to Embodiments 7, 8 and 9 of this disclosure are shown. Detailed Implementation

[0045] To better understand this disclosure, various aspects of this disclosure will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this disclosure and are not intended to limit the scope of this disclosure in any way. Throughout the specification, the same reference numerals refer to the same elements.

[0046] It should be noted that in this specification, the terms "first," "second," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of this disclosure, the first lens discussed below may also be referred to as the second lens.

[0047] In the accompanying 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 illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not drawn strictly to scale.

[0048] In this paper, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity 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 location of the concaveness 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.

[0049] It should also be understood that the terms "comprising" and / or "having," 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. Furthermore, when describing embodiments of this disclosure, the word "may" is used to mean "one or more embodiments of this disclosure." And the term "exemplary" is intended to refer to an example or illustration.

[0050] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense, unless expressly so specified herein.

[0051] It should be noted that, unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other. This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0052] The features, principles and other aspects of this disclosure are described in detail below.

[0053] Figure 1 This is a schematic diagram illustrating the structural layout and parameters of a visual system according to an exemplary embodiment of this disclosure, to facilitate a better understanding of this disclosure. Figure 1 As shown, das is the inner diameter of the first side end face of the first lens barrel, dam is the inner diameter of the second side end face of the first lens barrel, Das is the outer diameter of the first side end face of the first lens barrel, Dam is the outer diameter of the second side end face of the first lens barrel, dbs is the inner diameter of the first side end face of the second lens barrel, dbm is the inner diameter of the second side end face of the second lens barrel, Dbs is the outer diameter of the first side end face of the second lens barrel, Dbm is the outer diameter of the second side end face of the second lens barrel, dcs is the inner diameter of the first side end face of the third lens barrel, and dcm is the inner diameter of the third lens barrel. The inner diameter of the second side end face of the tube, Dcs is the outer diameter of the first side end face of the third tube, Dcm is the outer diameter of the second side end face of the third tube, La is the distance between the first side end face and the second side end face of the first tube along the optical axis, Lb is the distance between the first side end face and the second side end face of the second tube along the optical axis, Lc is the distance between the first side end face and the second side end face of the third tube along the optical axis, and Lac is the distance between the second side end face and the first side end face of the third tube along the optical axis.

[0054] The first aspect of this disclosure provides a visual system that may include an optical element group, which may include a first lens, a reflective polarizing element, a quarter-wave plate, a second lens, a partially reflective element, and a third lens arranged sequentially along an optical axis from a first side to a second side. By utilizing the reflective polarizing element, the quarter-wave plate, and the partially reflective element, optical path reflection can be achieved, effectively shortening the overall length of the visual system, reducing its size and weight, and achieving a lightweight visual system.

[0055] In an exemplary embodiment, the first lens may have positive optical power. The first side surface of the first lens may be convex, and the second side surface may be planar.

[0056] In an exemplary embodiment, the second lens may have positive optical power. The first side surface of the second lens may be convex, and the second side surface may also be convex.

[0057] In an exemplary embodiment, the third lens may have positive optical power. The first side of the third lens may be concave or flat, and the second side may be convex.

[0058] In an exemplary embodiment, the visual system may have three lenses with optical power. Each lens has at least one first side facing a first side and one second side facing a second side. Each lens has an effective diameter region that allows light to pass through and a non-effective diameter region surrounding the effective diameter region that does not allow light to pass through. In the first to third lenses, any two adjacent lenses may have a gap on the optical axis, which may be, for example, an air gap.

[0059] In an exemplary embodiment, the reflective polarizing element and the quarter-wave plate can be attached to each other and to a second side surface of the first lens. For example, the reflective polarizing element is at least partially attached to the second side surface of the first lens, and the quarter-wave plate is at least partially attached to the second side surface of the reflective polarizing element. The quarter-wave plate can be used to change the polarization state of light, for example, converting circularly polarized light into linearly polarized light, or converting linearly polarized light into circularly polarized light. The reflective polarizing element can reflect light in a predetermined direction (e.g., linearly polarized light) and transmit light in a direction orthogonal to the predetermined direction (e.g., linearly polarized light).

[0060] In an exemplary embodiment, a partial reflective element may be located on the second side of the second lens and at least partially abutted against the second side of the second lens. The partial reflective element can have a semi-transmissive and semi-reflective effect on light. By providing a partial reflective element on the second side of the second lens, and combining it with a reflective polarizing element and a quarter-wave plate, light can be refracted multiple times, effectively reducing the body length of the visual system.

[0061] In an exemplary embodiment, the visual system may further include an aperture stop, which may be disposed between the first side and the first lens. Image light from the second side is transmitted to the aperture stop after multiple refractions and reflections through a third lens, a partial reflective element, a second lens, a quarter-wave plate, a reflective polarizing element, and the first lens, and finally forms a virtual image at a predetermined position. As an example, the aperture stop may be, for example, the pupil of a user's eye.

[0062] In an exemplary embodiment, a second side of the visual system may be provided with an image surface. The image surface may be provided with a display screen. Image light from the display screen sequentially passes through a third lens, a second lens, and a quarter-wave plate, reaching a reflective polarizing element, and is then reflected 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, and reaches a partial reflective element on the second side of the second lens, where it is reflected to form a second reflected image light. The second reflected image light sequentially passes through the second lens, the quarter-wave plate, the reflective polarizing element, and the first lens to an aperture stop (e.g., the user's pupil) and finally forms an image at a predetermined position. The visual system provided by this disclosure effectively shortens the overall length of the visual system by folding the required optical path through a combination of light reflection and refraction without affecting projection quality.

[0063] In an exemplary embodiment, the first and third lenses are fixed in position relative to the image plane along the optical axis. The second lens is movable relative to the first lens along the optical axis, meaning the distance between the second lens and the first lens along the optical axis is adjustable. By moving the second lens, the visual system can switch between a first state and a second state, thereby adjusting the diopter of the visual system to meet the needs of users with different diopter levels, such as users with diopter levels from +2D to -5D.

[0064] When the visual system is in its first state, its refractive power is +2D, suitable for users with a refractive power of +2D. When the visual system is in its second state, its refractive power is -5D, suitable for users with a refractive power of -5D. A negative sign for refractive power indicates that the user is myopic; a positive sign indicates that the user is hyperopic. The specific numerical value of refractive power represents the user's degree of refractive error. For example, a refractive power of +1D indicates that the user's hyperopia is approximately 100 degrees, and a refractive power of -1D indicates that the user's myopia is approximately 100 degrees.

[0065] It should be understood that the visual system having two states (e.g., a first state and a second state) is merely exemplary, and the visual system may also have at least one other state besides the first state and the second state. When the visual system is in other states, the diopter of the visual system is between +2D and -5D. This disclosure does not impose a specific limitation on the number of states that the visual system may have.

[0066] In an exemplary embodiment, the virtual image distance of the visual system differs between the first state and the second state. The virtual image distance can be, for example, the axial distance from the virtual image formed by the image light from the second side at a predetermined position to the aperture. Here, VID = 1000 / diopter.

[0067] In an exemplary embodiment, the visual system may further include a lens barrel assembly. The lens barrel assembly may include a first lens barrel, a second lens barrel, and a third lens barrel, wherein a first lens is disposed within the first lens barrel, a second lens is disposed within the second lens barrel, and a third lens is disposed within the third lens barrel. Each lens barrel (e.g., the first lens barrel, the second lens barrel, and the third lens barrel) may include a first side end face, a second side end face, an outer annular surface, and an inner annular surface, wherein the end face of the lens barrel closest to the first side is the first side end face of the lens barrel, and the end face of the lens barrel closest to the second side is the second side end face of the lens barrel; in a direction perpendicular to the optical axis, the surface of the lens barrel furthest 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.

[0068] In an exemplary embodiment, the visual system can satisfy: 1.0 < f2 / (dbs + dbm) < 1.3, 2.8 < Lac / ΔL < 3.6, where f2 is the effective focal length of the second lens, dbs is the inner diameter of the first side end face of the second barrel, dbm is the inner diameter of the second side end face of the second barrel, Lac is the distance along the optical axis between the second side end face of the first barrel and the first side end face of the third barrel, and ΔL is the movable distance of the second lens when the visual system switches between the first state and the second state. By constraining f2 / (dbs + dbm) and Lac / ΔL within reasonable ranges respectively, the visual system can be switched between the first state and the second state, realizing the diopter adjustment of the visual system. For example, the diopter of the visual system can be adjusted between +2D and -5D, so as to adapt to the different diopters, different viewing distances, different application scenarios, etc. of users, and is also beneficial to reducing problems such as glare and ghosting, and improving the imaging quality of the visual system in different states.

[0069] In an exemplary embodiment, the visual system can satisfy: 3.90 ≤ (Das - das) / La ≤ 5.74, where das is the inner diameter of the first side end face of the first barrel, Das is the outer diameter of the first side end face of the first barrel, and La is the distance along the optical axis between the first side end face of the first barrel and the second side end face of the first barrel. By controlling the above conditional formula, the ratio of the wall thickness of the first barrel (such as the difference between the outer diameter and the inner diameter of the first barrel) to the length of the first barrel in the direction of the optical axis can be constrained within a reasonable range, which is beneficial to enhancing the structural strength and stability of the first barrel, and尽可能 reducing the deformation or damage of the first barrel caused by external forces, thereby enhancing the overall performance and reliability of the visual system; at the same time, it is also possible to reduce the weight of the visual system by optimizing the size and material of the first barrel while ensuring the structural strength of the first barrel and the performance of the visual system, thereby enhancing the portability of the visual system and the user experience. In addition, the reasonable parameter range of the first barrel is beneficial to simplifying the manufacturing process of the first barrel, reducing unnecessary material use and processing steps, improving production efficiency and reducing costs while ensuring the manufacturing yield of the first barrel; it can also make the first barrel have good adaptability and compatibility, and better cooperate with different types of lenses, polarizing elements or other optical components, so as to meet a wider range of application scenarios.

[0070] In an exemplary embodiment, the visual system can satisfy the condition: 1.29 ≤ fg / (dam+Dam) ≤ 1.55, where fg is the combined focal length of the first lens, the reflective polarizing element, and the quarter-wave plate, dam is the inner diameter of the second side end face of the first lens barrel, and Dam is the outer diameter of the second side end face of the first lens barrel. By controlling the above condition, the ratio of the combined focal length of the first lens, the reflective polarizing element, and the quarter-wave plate to the sum of the inner and outer diameters of the second side end face of the first lens barrel can be constrained within a reasonable range. This ensures that the size of the first lens barrel is well matched with the focal length of the element group formed by the first lens, the reflective polarizing element, and the quarter-wave plate, improving the stability of the entire visual system and reducing system performance fluctuations caused by factors such as vibration or temperature changes. Furthermore, the visual system satisfying the above condition has good adaptability and can be applied to different observation distances, different observation angles, and different lighting conditions, exhibiting excellent performance in a wider range of applications. During manufacturing and assembly, controlling the size of the first lens barrel and the focal length of the element group according to the above parameter range simplifies the manufacturing process, improves assembly accuracy, and reduces production costs.

[0071] In an exemplary embodiment, the visual system may satisfy: 1.45≤(CT1+CTR+CTQ) / La≤1.81, where CT1 is the center thickness of the first lens on the optical axis, CTR is the center thickness of the reflective polarizing element on the optical axis, CTQ is the center thickness of the quarter-wave plate on the optical axis, and La is the distance along the optical axis between the first side end face and the second side end face of the first lens barrel. By controlling the above-mentioned conditions, the center thicknesses of the first lens, the reflective polarizing element, and the quarter-wave plate, as well as the length of the first lens barrel along the optical axis, can be constrained. This makes the visual system more compact, reducing its overall size and weight, and improving its portability and ease of use. The compact design also reduces internal thermal expansion and contraction, improving thermal stability and facilitating use in environments with large temperature variations or for extended periods. Furthermore, the length ratio of the component group (e.g., the group formed by the first lens, reflective polarizing element, and quarter-wave plate) to the first lens barrel can be limited, optimizing the optical performance of the visual system. This ensures accurate light transmission through the component group and the first lens barrel, reducing aberrations and distortion, and improving the clarity and contrast of the image formed by the visual system. In addition, a visual system satisfying the above conditions exhibits excellent manufacturing and assembly precision, with precise control over the dimensions and positions of each component, ensuring the system meets performance requirements and enhancing its reliability and durability.

[0072] In an exemplary embodiment, the visual system may satisfy: 3.45 < CT2 / |Dbs - Dbm| < 5.0, where CT2 is the central thickness of the second lens on the optical axis, Dbs is the outer diameter of the first side end face of the second barrel, and Dbm is the outer diameter of the second side end face of the second barrel. By controlling the above conditional expression, the ratio of the central thickness of the second lens on the optical axis to the difference between the outer diameters of the two side end faces of the second barrel can be constrained within a reasonable range, which is beneficial for the second lens to be well assembled in the second barrel, effectively utilize the space inside the second barrel, reduce unnecessary material use, achieve a tight fit between the second lens and the second barrel, and improve the optical performance and stability of the visual system. In addition, the visual system satisfying the above conditional expression is easier to achieve the alignment and fixation of the second lens and the second barrel during the assembly process, simplifies the assembly process, improves production efficiency, and reduces the error rate during the assembly process.

[0073] In an exemplary embodiment, the visual system may satisfy: 1.85 < R1 / das < 2.25, where R1 is the radius of curvature of the first side face of the first lens, and das is the inner diameter of the first side end face of the first barrel. By controlling the above conditional expression, the ratio of the radius of curvature of the first side face of the first lens to the inner diameter of the first side end face of the first barrel can be constrained within a reasonable range, which is beneficial for reducing aberrations, especially spherical aberrations, and improving the imaging quality of the visual system; at the same time, it can also make the light more focused when passing through the first side face of the first lens, reduce scattering and dispersion, and ensure that the image formed by the visual system is clearer and sharper. In addition, the visual system satisfying the above conditional expression has good stability. For example, under the influence of external factors such as vibration or temperature change, the visual system can still maintain stable imaging performance and reduce image distortion or blurring caused by the deformation of the first lens or the first barrel.

[0074] In an exemplary embodiment, the visual system may satisfy: 8.25 < dcs / CT3 < 12.55, where dcs is the inner diameter of the first side end face of the third barrel, and CT3 is the central thickness of the third lens on the optical axis. By controlling the above conditional expression, the ratio of the inner diameter of the first side end face of the third barrel to the central thickness of the third lens on the optical axis can be constrained within a reasonable range, more effectively layout the third lens and the third barrel in a limited space, thereby optimizing the structure of the entire visual system; at the same time, it can also reduce the scattering and reflection of light between the third lens and the third barrel, improve the light transmittance and imaging quality of the visual system, and reduce aberrations and distortions, making the image formed by the visual system clearer and sharper. In addition, the visual system satisfying the above conditional expression has good stability. For example, under the influence of external factors such as vibration or temperature change, the visual system can still maintain stable imaging performance and reduce image distortion or blurring caused by the deformation of the third lens or the third barrel.

[0075] In an exemplary embodiment, the visual system may satisfy: 2.9 < Lb / Δf < 3.85, where Lb is the distance along the optical axis between the first side end face of the second lens barrel and the second side end face of the second lens barrel, and Δf is the difference between the total effective focal length of the visual system in the first state and the total effective focal length of the visual system in the second state. By controlling the above conditional expression, the ratio of the length of the second lens barrel in the direction of the optical axis to the change amount of the total effective focal length of the visual system can be constrained within a reasonable range, which is beneficial to optimizing the performance of the visual system, enabling the visual system to maintain a smooth and stable diopter adjustment effect when switching between the first state and the second state; at the same time, it can also reduce the aberration change caused by the movement of the second lens during the diopter adjustment process and improve the imaging quality of the visual system. For example, it reduces spherical aberration, coma, astigmatism, and distortion, etc., so that the image formed by the visual system can remain clear and sharp at different diopters. In addition, the visual system that satisfies the above conditional expression has good stability. For example, during the diopter adjustment process, the movement of the second lens is more stable, reducing image jitter or blurring caused by mechanical vibration or instability. "2.9 < Lb / Δf < 3.85" can enable the visual system to better adapt to different application scenarios and observation requirements. For example, it can adapt to scenarios such as different diopters, different observation distances, or different light conditions.

[0076] In an exemplary embodiment, the visual system may satisfy: 2.5 < f1 / Das < 3.1, where f1 is the effective focal length of the first lens and Das is the outer diameter of the first side end face of the first lens barrel. By controlling the above conditional expression, the ratio of the effective focal length of the first lens to the outer diameter of the first side end face of the first lens barrel can be constrained within a reasonable range, making the light more focused when passing through the first lens, reducing scattering and dispersion, and improving the clarity and contrast of the image formed by the visual system. In addition, the visual system that satisfies the above conditional expression has good stability. For example, under the influence of external factors such as vibration or temperature change, the visual system can still maintain stable imaging performance, reducing image distortion or blurring caused by the deformation of the first lens or the first lens barrel. During the assembly and calibration process, it is easier to align and fix the first lens with the first lens barrel according to the above parameter range, simplifying the assembly process, improving production efficiency, and reducing the error rate during the assembly and calibration process.

[0077] In an exemplary embodiment, the visual system may satisfy: 1.1 < Lc / |Dcs - Dcm| < 2.5, where Lc is the distance along the optical axis between the first side end face and the second side end face of the third lens barrel, Dcs is the outer diameter of the first side end face of the third lens barrel, and Dcm is the outer diameter of the second side end face of the third lens barrel. By controlling the above conditional expression, the ratio of the length of the third lens barrel in the direction of the optical axis to the difference in the outer diameters of the two side end faces of the third lens barrel can be constrained within a reasonable range, which is beneficial to improving the structural strength of the third lens barrel, enabling the third lens barrel to remain stable when承受外部压力或振动时仍能够保持稳定,减少第三镜筒的形变或损坏;同时还可以对第三镜筒的尺寸和形状进行限制,减少不必要的材料使用,降低生产成本。此外,满足上述条件式的目视系统能够更好地适应不同的应用场景和观察条件,例如,适应不同屈光度、不同视场角或不同光线条件等场景,从而满足更广泛的应用需求。稳定的系统性能、优化的材料使用和简化的装配过程可以使得用户更轻松、更舒适地操作和观察目视系统,从而提升用户的使用体验。

[0078] In an exemplary embodiment, the visual system may satisfy: -1.55 < R4 / dbm < -1.15, where R4 is the radius of curvature of the second side face of the second lens, and dbm is the inner diameter of the second side end face of the second lens barrel. By controlling the above conditional expression, the radius of curvature of the second side face of the second lens and the inner diameter of the second side end face of the second lens barrel can be constrained within a reasonable range, optimizing the refraction path of light when passing through the second lens, making the light more precisely focused on the imaging surface, and improving the imaging quality of the visual system; at the same time, it is also beneficial to improve the stability of the visual system. For example, under the influence of external factors such as vibration or temperature change, the visual system can still maintain stable imaging performance, reducing image distortion or blurring caused by deformation of the second lens or the second lens barrel. In addition, according to the above parameter range, the materials and dimensions of the second lens and the second lens barrel can be more reasonably selected, reducing unnecessary material use, lowering production costs, and enhancing the cost performance and market competitiveness of the visual system.

[0079] It should be noted that there are some Chinese characters that seem to be incorrect or incomplete in the original content (such as "承受外部压力或振动时仍能够保持稳定" in the first paragraph), which may affect the understanding and translation. You may want to check and correct the original text for a more accurate translation.In an exemplary embodiment, the visual system may satisfy: 1.65 ≤ f3 / (dcm + Dcm) ≤ 3.09, where f3 is the effective focal length of the third lens, dcm is the inner diameter of the second side end face of the third lens barrel, and Dcm is the outer diameter of the second side end face of the third lens barrel. By controlling the above conditional expression, the ratio of the effective focal length of the third lens to the sum of the inner and outer diameters of the second side end face of the third lens barrel can be constrained within a reasonable range, optimizing the refraction and focusing effects of light when passing through the third lens, improving the imaging quality of the visual system, and reducing aberrations such as spherical aberration, coma, and astigmatism, making the image formed by the visual system clearer and sharper; at the same time, it can also make the structure of the visual system more compact, reduce the overall size and weight of the visual system, and ensure that the visual system is more portable and easier to operate.

[0080] In an exemplary embodiment, the visual system may satisfy: 2.15 < TD / Lac < 2.5, where TD is the on-axis distance from the first side face of the first lens to the second side face of the third lens, and Lac is the distance along the optical axis between the second side end face of the first lens barrel and the first side end face of the third lens barrel. By controlling the above conditional expression, the refraction and focusing effects of light when passing through multiple lenses can be optimized, improving the imaging quality of the visual system; at the same time, it can also make the structure of the visual system more compact, reduce the overall size and weight of the visual system, and ensure that the visual system is more portable and easier to operate to adapt to highly integrated or space-constrained application scenarios. In addition, the visual system that satisfies the above conditional expression can better adapt to different application scenarios and observation conditions. For example, it can adapt to scenarios such as different diopters, different field angles, or different light conditions, thus meeting a wider range of application requirements. High-quality imaging, stable system performance, compact structural design, and optimized assembly and calibration processes can enable users to operate and observe the visual system more easily and comfortably.

[0081] In an exemplary embodiment, the visual system can satisfy: 1.45 < (La + Lc) / Lb < 2.9, where La is the distance along the optical axis between the first and second side end faces of the first lens barrel, Lb is the distance along the optical axis between the first and second side end faces of the second lens barrel, and Lc is the distance along the optical axis between the first and second side end faces of the third lens barrel. By controlling the above conditional expression, the structural strength of each lens barrel can be optimized, enabling each lens barrel to remain stable under external pressure, vibration, or temperature changes, reducing deformation or damage to each lens barrel; at the same time, while ensuring the structural strength of each lens barrel, unnecessary material usage can be reduced, lowering production costs to adapt to large-scale production or cost-sensitive application scenarios. Furthermore, a visual system satisfying the above conditional expression makes it easier to align and fix each component during assembly, simplifying the assembly process, improving production efficiency, and reducing the error rate during assembly. In some applications, the length of the lens barrel along the optical axis may affect the thermal management performance of the visual system. By controlling the length of each lens barrel to meet the above range, the heat transfer and heat dissipation effect can be optimized, so that the visual system can maintain stable performance in high-temperature environments or long-term use.

[0082] In an exemplary embodiment, the visual system can satisfy: 1.55 ≤ (Das + Dcs) / Dbs ≤ 1.89, where Das is the outer diameter of the first side end face of the first lens barrel, Dbs is the outer diameter of the first side end face of the second lens barrel, and Dcs is the outer diameter of the first side end face of the third lens barrel. By controlling the above condition, the space allocation between the lens barrels can be made reasonable, avoiding excessive gaps or overlaps, and improving the compactness and integration of the visual system. At the same time, it can also ensure that the relative positions of the lens barrels remain stable when subjected to external pressure, vibration, or temperature changes, reducing lens barrel offset or deformation and improving the stability of the visual system. In addition, a visual system that satisfies the above condition makes it easier to align and fix the components during assembly. For example, a reasonable ratio of the outer diameters between the lens barrels can reduce unnecessary adjustments and corrections during assembly, improve assembly efficiency and accuracy, and while ensuring the structural strength of each lens barrel, adjusting the ratio of the outer diameters between the lens barrels can reduce unnecessary material usage and lower production costs, making it suitable for large-scale production or cost-sensitive applications. A reasonable ratio of the outer diameters between the lens barrels also helps improve manufacturing precision. For example, during the manufacturing process, because the dimensional relationships between the lens barrels are clear, manufacturing errors can be more easily controlled, ensuring that the size and shape of each lens barrel meet the requirements. A reasonable ratio of the outer diameters between the lens barrels also enables the visual system to better adapt to different application scenarios and observation conditions, such as different refractive powers, different fields of view, different lighting conditions, or different mechanical requirements, thereby meeting a wider range of application needs.

[0083] The visual system according to the above embodiments of the present disclosure may employ multiple lenses, such as the three lenses described above. By reasonably allocating the parameters of the reflective polarizing element, quarter-wave plate, each lens, and each lens barrel, the body length of the visual system can be reduced, the imaging quality of the visual system can be improved, and at the same time, the diopter adjustment of the visual system can be achieved, enabling users with a diopter between +2D and -5D to see clear images. The visual system configured as described above has characteristics such as diopter adjustment, thinning, and good imaging quality, and can well meet the usage requirements of various portable electronic products in the projection scenario.

[0084] In an embodiment of the present disclosure, at least one of the surfaces of the first lens, the second lens, and the third lens is an aspherical surface. The characteristics of an aspherical lens are that the curvature continuously changes from the center of the lens to the periphery of the lens. Different from a spherical lens with a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has better curvature radius characteristics and has the advantages of improving distortion aberration and astigmatism aberration. After using an aspherical lens, it is possible to eliminate the aberration that appears during imaging as much as possible, thereby improving the imaging quality.

[0085] A second aspect of the present disclosure provides such a visual system, which includes an optical element group and a lens barrel assembly. The optical element group sequentially includes a first lens with positive optical power, a reflective polarizing element, a quarter-wave plate, a second lens with positive optical power, a partial reflection element, and a third lens with positive optical power 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, and the second side is convex. The second side of the third lens is convex. The lens barrel assembly includes a first lens barrel, a second lens barrel, and a third lens barrel. The first lens is placed in the first lens barrel, the second lens is placed in the second lens barrel, and the third lens is placed in the third lens barrel. Among them, the position of the first lens on the optical axis relative to the image plane on the second side is fixed, and the distance of the second lens on the optical axis relative to the first lens is adjustable. The number of lenses with optical power in the visual system is three. The visual system satisfies: 2.9 < Lb / Δf < 3.85, 2.8 < Lac / ΔL < 3.6, where Lb is the distance along the optical axis between the first-side end face and the second-side end face of the second lens barrel, Δf is the difference between the total effective focal length of the visual system in the first state and the total effective focal length of the visual system in the second state, Lac is the distance along the optical axis between the second-side end face of the first lens barrel and the first-side end face of the third lens barrel, and ΔL is the movable distance of the second lens when the visual system switches between the first state and the second state.

[0086] The visual system disclosed herein utilizes a reflective polarizing element, a quarter-wave plate, and a partially reflective element to achieve optical path refraction, and the diopter adjustment of the visual system can be achieved by moving the second lens. Simultaneously, by constraining Lb / Δf and Lac / ΔL within reasonable ranges, the visual system can switch between a first state and a second state, ensuring a smooth and stable diopter adjustment effect during the transition. Furthermore, it reduces aberration changes caused by the movement of the second lens during diopter adjustment, improving the imaging quality of the visual system. For example, it reduces spherical aberration, coma, astigmatism, and distortion, ensuring that the image formed by the visual system remains clear and sharp at different diopters. The visual system disclosed herein is better adapted to different application scenarios and observation needs, such as scenarios with different diopters, different observation distances, or different lighting conditions.

[0087] However, those skilled in the art will understand that, without departing from the technical solutions claimed in this disclosure, the number of lenses constituting the visual system can be changed to obtain the various results and advantages described in this specification.

[0088] Specific embodiments of the visual system applicable to the above-described embodiments are further described below with reference to the accompanying drawings.

[0089] Example 1

[0090] The following reference Figure 2 and Figure 3 The visual system of Embodiment 1 of this disclosure is described.

[0091] like Figure 2 and Figure 3 As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc.

[0092] The optical element assembly may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3, arranged sequentially along the optical axis from a first side to a second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1. In this embodiment, the first side refers to the human eye side, and the second side refers to the display screen side.

[0093] The first lens E1 has positive optical power, with its first side surface S1 being convex and its second side surface S2 being flat. The second lens E2 has positive optical power, with its first side surface S3 being convex and its second side surface S4 being convex. The third lens E3 has positive optical power, with its first side surface S5 being concave and its second side surface S6 being convex. A reflective polarizing element RP and a quarter-wave plate QWP are attached to the second side surface S2 of the first lens E1. A partially reflective element BS is attached to the second side surface S4 of the second lens E2. It should be noted that surfaces S1, S2, S3, S4, S5, and S6 are... Figure 2 and Figure 3 Not shown in the image.

[0094] In this example, an image plane (IMG) may be provided on the second side of the visual system, and the image plane (IMG) may, for example, be a display screen. Image light from the image plane (IMG) sequentially passes through a third lens (E3), a second lens (E2), a quarter-wave plate (QWP), and reaches a reflective polarizing element (RP), where it undergoes a first reflection. The light after the first reflection passes through the quarter-wave plate (QWP), the second lens (E2), and reaches a partial reflective element (BS) located on the second side of the second lens, where it undergoes a second reflection. The light after the second reflection sequentially passes through the second lens (E2), the quarter-wave plate (QWP), the reflective polarizing element (RP), and the first lens (E1) to the aperture stop and finally forms an image at a predetermined position. For example, the light from this visual system, after two reflections, is ultimately projected onto the user's pupil.

[0095] Table 1 shows the basic parameters of the visual system of Embodiment 1, where the units for radius of curvature and thickness / distance are millimeters (mm). Image light from the image plane IMG passes through each element in the order of number 15 to number 1 and is finally projected onto the user's pupil.

[0096] Table 1

[0097]

[0098]

[0099] 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 aspherical surfaces. The surface shape of each aspherical surface can be defined by, but is not limited to, the following formula:

[0100]

[0101] Where x is the distance vector from the vertex of the aspherical surface at a height h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 2 gives the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for surfaces S1, S3, S4, S5 and S6 in Example 1.

[0102] Table 2

[0103] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 -2.4290E-06 8.5145E-08 -3.7998E-10 8.4167E-13 -9.6417E-16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S3 9.1121E-06 -7.5641E-08 3.9449E-11 2.5182E-13 -1.3614E-16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S4 -2.4825E-07 -9.9591E-09 -1.4896E-11 9.7420E-14 -4.2552E-17 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S5 -5.6259E-05 2.2618E-07 4.5696E-10 -3.0363E-12 7.8493E-15 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S6 -5.1283E-05 3.1903E-07 -2.1205E-10 -8.1681E-13 9.7622E-15 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0104] In this embodiment, the visual system has a first state (e.g., Figure 2 ) and the second state (e.g., Figure 3 The virtual image distance of the visual system is taken as W1, the interval between the quarter-wave plate and the second lens is taken as W2, and the interval between the second lens and the third lens is taken as W3. W1, W2, and W3 are variables that can change with the state of the visual system.

[0105] Table 3 shows the values ​​of W1, W2, W3 and the total effective focal length f of the visual optics in different states of the visual system in Example 1.

[0106] Table 3

[0107] state W1(mm) W2(mm) W3(mm) f(mm) First state 500.0000 2.6900 0.5000 16.70 Second state -200.0000 0.5000 2.6900 15.51

[0108] Example 2

[0109] The following reference Figure 4 and Figure 5 The visual system of Embodiment 2 of this disclosure is described.

[0110] like Figure 4 and Figure 5 As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc. The optical element group may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3, arranged sequentially along the optical axis from the first side to the second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1.

[0111] The structure of the optical element group in this embodiment is the same as that in Embodiment 1. That is, the basic parameter table of the visual system in this embodiment is the same as Table 1, the aspherical coefficient table is the same as Table 2, and the tables for W1, W2, W3, and f are the same as Table 3. The difference between this embodiment and Embodiment 1 is that at least some of the components in the lens barrel assembly have different structural dimensions.

[0112] Example 3

[0113] The following reference Figure 6 and Figure 7 The visual system of Embodiment 3 of this disclosure is described.

[0114] like Figure 6 and Figure 7 As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc. The optical element group may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3, arranged sequentially along the optical axis from the first side to the second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1.

[0115] The structure of the optical element group in this embodiment is the same as that in Embodiment 1. That is, the basic parameter table of the visual system in this embodiment is the same as Table 1, the aspherical coefficient table is the same as Table 2, and the tables for W1, W2, W3, and f are the same as Table 3. The difference between this embodiment and Embodiment 1 is that at least some of the components in the lens barrel assembly have different structural dimensions.

[0116] Figure 8 The modulation transfer function curves of the visual systems of Embodiments 1, 2, and 3 in the first state are shown. Figure 9 The modulation transfer function curves of the visual systems of Embodiments 1, 2, and 3 in their second state are shown. From Figure 8 and Figure 9 As can be seen, the visual systems given in Examples 1, 2 and 3 can achieve good imaging quality in both the first and second states.

[0117] Example 4

[0118] The following reference Figure 10 and Figure 11 The visual system of Embodiment 4 of this disclosure is described.

[0119] like Figure 10 and Figure 11 As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc.

[0120] The optical element assembly may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3, arranged sequentially along the optical axis from a first side to a second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1. In this embodiment, the first side refers to the human eye side, and the second side refers to the display screen side.

[0121] The first lens E1 has positive optical power, with its first side surface S1 being convex and its second side surface S2 being flat. The second lens E2 has positive optical power, with its first side surface S3 being convex and its second side surface S4 being convex. The third lens E3 has positive optical power, with its first side surface S5 being concave and its second side surface S6 being convex. A reflective polarizing element RP and a quarter-wave plate QWP are attached to the second side surface S2 of the first lens E1. A partially reflective element BS is attached to the second side surface S4 of the second lens E2. It should be noted that surfaces S1, S2, S3, S4, S5, and S6 are... Figure 10 and Figure 11 Not shown in the image.

[0122] In this example, an image plane (IMG) may be provided on the second side of the visual system, and the image plane (IMG) may, for example, be a display screen. Image light from the image plane (IMG) sequentially passes through a third lens (E3), a second lens (E2), a quarter-wave plate (QWP), and reaches a reflective polarizing element (RP), where it undergoes a first reflection. The light after the first reflection passes through the quarter-wave plate (QWP), the second lens (E2), and reaches a partial reflective element (BS) located on the second side of the second lens, where it undergoes a second reflection. The light after the second reflection sequentially passes through the second lens (E2), the quarter-wave plate (QWP), the reflective polarizing element (RP), and the first lens (E1) to the aperture stop and finally forms an image at a predetermined position. For example, the light from this visual system, after two reflections, is ultimately projected onto the user's pupil.

[0123] Table 4 shows the basic parameters of the visual system of Embodiment 4, where the units for radius of curvature and thickness / distance are millimeters (mm). Image light from the image plane IMG passes through each element in the order of number 15 to number 1 and is finally projected onto the user's pupil.

[0124] Table 4

[0125]

[0126]

[0127] 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 aspherical surfaces. Table 5 shows the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 of the surfaces S1, S3, S4, S5 and S6 that can be used in Embodiment 4.

[0128] Table 5

[0129] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 -4.1213E-06 9.1886E-08 -4.4712E-10 1.0119E-12 -7.1868E-16 -2.8375E-18 5.3340E-21 0.0000E+00 0.0000E+00 S3 2.2218E-05 -1.4167E-07 1.5957E-10 4.4994E-13 -6.1740E-16 -3.0075E-19 -4.8006E-23 0.0000E+00 0.0000E+00 S4 1.9785E-06 -1.4811E-08 -3.8796E-11 2.2860E-13 -1.9977E-16 9.1843E-20 -3.3541E-22 0.0000E+00 0.0000E+00 S5 -1.1386E-04 5.3595E-07 8.3880E-10 -8.0735E-12 9.0532E-15 -1.9171E-18 5.8508E-20 0.0000E+00 0.0000E+00 S6 -1.2430E-04 8.7665E-07 -7.3836E-10 -6.8129E-12 1.0913E-14 -1.0592E-18 8.9915E-20 0.0000E+00 0.0000E+00

[0130] In this embodiment, the visual system has a first state (e.g., Figure 10 ) and the second state (e.g., Figure 11 W1, W2, and W3 are variables that can change as the state of the visual system changes.

[0131] Table 6 shows the values ​​of W1, W2, W3 and the total effective focal length f of the visual optics in different states of the visual system in Example 4.

[0132] Table 6

[0133] state W1(mm) W2(mm) W3(mm) f(mm) First state 500.0000 2.7736 0.5000 17.30 Second state -200.0000 0.5000 2.7736 16.06

[0134] Example 5

[0135] The following reference Figure 12 and Figure 13 The visual system of Embodiment 5 of this disclosure is described.

[0136] like Figure 12 and Figure 13 As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc. The optical element group may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3, arranged sequentially along the optical axis from the first side to the second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1.

[0137] The structure of the optical element group in this embodiment is the same as that in Embodiment 4. That is, the basic parameter table of the visual system in this embodiment is the same as Table 4, the aspherical coefficient table is the same as Table 5, and the tables for W1, W2, W3, and f are the same as Table 6. The difference between this embodiment and Embodiment 4 is that at least some of the components in the lens barrel assembly have different structural dimensions.

[0138] Example 6

[0139] The following reference Figure 14 and Figure 15The visual system of Embodiment 6 of this disclosure is described.

[0140] like Figure 14 and Figure 15 As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc. The optical element group may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3, arranged sequentially along the optical axis from the first side to the second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1.

[0141] The structure of the optical element group in this embodiment is the same as that in Embodiment 4. That is, the basic parameter table of the visual system in this embodiment is the same as Table 4, the aspherical coefficient table is the same as Table 5, and the tables for W1, W2, W3, and f are the same as Table 6. The difference between this embodiment and Embodiment 4 is that at least some of the components in the lens barrel assembly have different structural dimensions.

[0142] Figure 16 The modulation transfer function curves of the visual systems of Embodiments 4, 5, and 6 in the first state are shown. Figure 17 The modulation transfer function curves of the visual systems in Embodiments 4, 5, and 6 when they are in the second state are shown. From Figure 16 and Figure 17 As can be seen, the visual systems given in Examples 4, 5 and 6 can achieve good imaging quality in both the first and second states.

[0143] Example 7

[0144] The following reference Figure 18 and Figure 19 The visual system of Embodiment 7 of this disclosure is described.

[0145] like Figure 18 and Figure 19 As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc.

[0146] The optical element assembly may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3, arranged sequentially along the optical axis from a first side to a second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1. In this embodiment, the first side refers to the human eye side, and the second side refers to the display screen side.

[0147] The first lens E1 has positive optical power, with its first side surface S1 being convex and its second side surface S2 being planar. The second lens E2 has positive optical power, with its first side surface S3 being convex and its second side surface S4 being convex. The third lens E3 has positive optical power, with its first side surface S5 being planar and its second side surface S6 being convex. A reflective polarizing element RP and a quarter-wave plate QWP are attached to the second side surface S2 of the first lens E1. A partially reflective element BS is attached to the second side surface S4 of the second lens E2. It should be noted that surfaces S1, S2, S3, S4, S5, and S6 are... Figure 18 and Figure 19 Not shown in the image.

[0148] In this example, an image surface IMG can be provided on the second side of the visual system, and the image surface IMG can, for example, be a display screen. Image light from the image surface IMG passes sequentially through the third lens E3, the second lens E2, the quarter-wave plate QWP, and reaches the reflective polarizing element RP, where it undergoes a first reflection. The light after the first reflection passes through the quarter-wave plate QWP, the second lens E2, and reaches the partial reflective element BS located on the second side of the second lens, where it undergoes a second reflection. The light after the second reflection passes sequentially through the second lens E2, the quarter-wave plate QWP, the reflective polarizing element RP, the first lens E1, to the aperture stop, and finally forms an image at a predetermined position. For example, the light after the two reflections is finally projected onto the user's pupil. A protective glass E4 can also be provided between the image surface IMG and the third lens E3.

[0149] Table 7 shows the basic parameters of the visual system of Embodiment 7, where the units for radius of curvature and thickness / distance are millimeters (mm). Image light from the image plane IMG passes through each element in the order of number 17 to number 1 and is finally projected onto the user's pupil.

[0150] Table 7

[0151]

[0152]

[0153] 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 aspherical surfaces. Table 8 gives the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 of the surfaces S1, S3, S4, S5 and S6 that can be used in Embodiment 7.

[0154] Table 8

[0155] Face number A4 A6 A8 A10 A12 A14 A16 A18 A20 S1 -1.9124E-05 1.7343E-07 -9.2758E-10 2.3573E-12 -2.9395E-15 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S3 2.7644E-05 -1.7094E-07 2.3086E-10 3.1010E-13 -5.8570E-16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S4 2.6785E-06 -1.8312E-08 -4.0205E-11 2.5114E-13 -2.4473E-16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S5 -1.8210E-04 1.1586E-06 -2.5603E-09 1.9931E-12 -8.3941E-16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S6 -1.6743E-04 9.2700E-07 -2.3992E-10 -8.4016E-12 1.6111E-14 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00

[0156] In this embodiment, the visual system has a first state (e.g., Figure 18 ) and the second state (e.g., Figure 19 W1, W2, and W3 are variables that can change as the state of the visual system changes.

[0157] Table 9 shows the values ​​of W1, W2, W3 and the total effective focal length f of the visual optics in different states of the visual system in Example 7.

[0158] Table 9

[0159] state W1(mm) W2(mm) W3(mm) f(mm) First state 500.0000 2.9280 0.5000 17.32 Second state -200.0000 0.5000 2.9280 16.14

[0160] Example 8

[0161] The following reference Figure 20 and Figure 21 The visual system of Embodiment 8 of this disclosure is described.

[0162] like Figure 20 and Figure 21 As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc. The optical element group may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3 arranged sequentially along the optical axis from the first side to the second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1. A protective glass E4 may also be disposed between the image plane IMG and the third lens E3.

[0163] The structure of the optical element group in this embodiment is the same as that in Embodiment 7. That is, the basic parameter table of the visual system in this embodiment is the same as Table 7, the aspherical coefficient table is the same as Table 8, and the tables for W1, W2, W3, and f are the same as Table 9. The difference between this embodiment and Embodiment 7 is that at least some of the components in the lens barrel assembly have different structural dimensions.

[0164] Example 9

[0165] The following reference Figure 22 and Figure 23 The visual system of Embodiment 9 of this disclosure is described.

[0166] like Figure 22 and Figure 23As shown, the visual system may include an optical element group and a lens barrel assembly. The lens barrel assembly may include a first lens barrel Pa, a second lens barrel Pb, and a third lens barrel Pc. The optical element group may include a first lens E1, a reflective polarizing element RP, a quarter-wave plate QWP, a second lens E2, a partial reflective element BS (not shown), and a third lens E3 arranged sequentially along the optical axis from the first side to the second side. An aperture stop STO (not shown) may be located on the object side of the first lens E1. A protective glass E4 may also be disposed between the image plane IMG and the third lens E3.

[0167] The structure of the optical element group in this embodiment is the same as that in Embodiment 7. That is, the basic parameter table of the visual system in this embodiment is the same as Table 7, the aspherical coefficient table is the same as Table 8, and the tables for W1, W2, W3, and f are the same as Table 9. The difference between this embodiment and Embodiment 7 is that at least some of the components in the lens barrel assembly have different structural dimensions.

[0168] Figure 24 The modulation transfer function curves of the visual systems of Embodiments 7, 8, and 9 in the first state are shown. Figure 25 The modulation transfer function curves of the visual systems in Embodiments 7, 8, and 9 when they are in the second state are shown. From Figure 24 and Figure 25 As can be seen, the visual systems given in Examples 7, 8 and 9 can achieve good imaging quality in both the first and second states.

[0169] Table 10 gives the basic parameters of each embodiment in Examples 1 to 9, such as the values ​​of f1, f2, f3, fg, TD, ΔL and Δf.

[0170] Table 10

[0171] Parameters / Examples 1 2 3 4 5 6 7 8 9 f1(mm) 114.20 114.20 114.20 122.93 122.93 122.93 135.28 135.28 135.28 f2 (mm) 99.72 99.72 99.72 106.75 106.75 106.75 103.40 103.40 103.40 f3 (mm) 123.78 123.78 123.78 113.90 113.90 113.90 200.61 200.61 200.61 fg(mm) 114.20 114.20 114.20 122.93 122.93 122.93 135.28 135.28 135.28 TD(mm) 17.00 17.00 17.00 17.00 17.00 17.00 16.20 16.20 16.20 ΔL(mm) 2.19 2.19 2.19 2.27 2.27 2.27 2.43 2.43 2.43 Δf(mm) 1.18 1.18 1.18 1.24 1.24 1.24 1.18 1.18 1.18

[0172] Table 11 provides the values ​​of parameters das, dam, Das, Dam, dbs, dbm, Dbs, Dbm, dcs, dcm, Dcs, Dcm, Lac, La, Lb, and Lc for each of Examples 1 to 9. These parameters can be calculated according to... Figure 1 The measurements were obtained using the annotation method shown, and the units of the parameters listed in Table 11 are all millimeters (mm).

[0173] Table 11

[0174] Parameters / Examples 1 2 3 4 5 6 7 8 9 das 32.760 33.056 33.022 32.404 32.508 32.376 33.470 33.630 33.694 dam 42.830 42.618 43.704 41.550 41.950 43.550 43.016 43.764 48.732 Das 44.006 45.176 45.148 42.728 43.806 44.728 44.192 45.192 49.908 Dam 44.006 45.176 45.148 42.728 43.806 44.728 44.192 45.192 49.908 dbs 44.740 43.364 43.244 43.896 49.882 45.882 43.758 43.688 45.460 dbm 50.714 38.844 38.848 49.870 42.756 38.756 49.734 50.782 41.348 Dbs 51.562 45.364 45.378 50.716 51.882 47.882 50.580 51.580 47.460 Dbm 52.714 43.972 43.968 51.870 50.490 46.490 51.734 52.734 45.866 DCS 31.514 31.580 35.682 36.260 37.336 36.316 32.970 39.348 38.348 dcm 36.190 36.310 28.230 28.964 29.128 28.858 44.658 29.596 28.596 DCS 36.146 35.890 37.682 38.260 39.158 38.224 39.174 41.014 40.014 Dcm 38.190 38.590 36.222 36.800 37.558 36.634 46.658 37.398 36.398 Lac 7.374 6.874 7.834 7.568 7.276 7.568 6.872 7.474 7.474 La 2.650 3.082 2.708 2.650 2.740 2.650 2.650 2.740 2.824 Lb 4.176 3.630 3.658 4.176 3.630 3.630 4.176 4.504 3.646 Lc 3.452 4.012 3.524 3.524 3.952 3.610 8.378 7.570 7.570

[0175] Table 12 gives the values ​​of the conditional expressions for each of the embodiments in Examples 1 to 9.

[0176] Table 12

[0177] Conditional / Example 1 2 3 4 5 6 7 8 9 f2 / (dbs+dbm) 1.04 1.21 1.21 1.14 1.15 1.26 1.11 1.09 1.19 Lac / ΔL 3.37 3.14 3.58 3.33 3.20 3.33 2.83 3.08 3.08 (Das-das) / La 4.24 3.93 4.48 3.90 4.12 4.66 4.05 4.22 5.74 fg / (dam+Dam) 1.32 1.30 1.29 1.46 1.43 1.39 1.55 1.52 1.37 (CT1+CTR+CTQ) / La 1.81 1.56 1.78 1.74 1.68 1.74 1.54 1.49 1.45 CT2 / |Dbs-Dbm| 4.51 3.73 3.68 4.99 4.14 4.14 4.80 4.80 3.48 R1 / das 1.91 1.89 1.89 2.08 2.07 2.08 2.21 2.20 2.20 DCS / CT3 8.28 8.30 9.38 10.79 11.11 10.81 10.49 12.52 12.20 Lb / Δf 3.53 3.07 3.09 3.37 2.93 2.93 3.53 3.81 3.09 f1 / Das 2.60 2.53 2.53 2.88 2.81 2.75 3.06 2.99 2.71 Lc / |Dcs-Dcm| 1.69 1.49 2.41 2.41 2.47 2.27 1.12 2.09 2.09 R4 / dbm -1.17 -1.53 -1.53 -1.20 -1.40 -1.54 -1.24 -1.22 -1.49 f3 / (dcm+Dcm) 1.66 1.65 1.92 1.73 1.71 1.74 2.20 2.99 3.09 TD / Lac 2.31 2.47 2.17 2.25 2.34 2.25 2.36 2.17 2.17 (La+Lc) / Lb 1.46 1.95 1.70 1.48 1.84 1.72 2.64 2.29 2.85 (Das+Dcs) / Dbs 1.55 1.79 1.83 1.60 1.60 1.73 1.65 1.67 1.89

[0178] This disclosure also provides an optical device, which can be a stand-alone projection device such as a projector, or a projection module integrated into a mobile electronic device such as a virtual reality device or an augmented reality device. The optical device is equipped with the visual system described above.

[0179] The above description is merely a preferred embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the utility model involved in this disclosure is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this disclosure.

Claims

1. A visual system, characterized in that, include: The optical element assembly, along the optical axis from the first side to the second side, includes: A first lens with positive optical power has a first convex surface and a second flat surface; Reflective polarizing element; Quarter wave plate; A second lens with positive optical power has a first convex side and a second convex side. Partial reflective elements; and The third lens has positive optical power, and its second side surface is convex. A lens barrel assembly includes a first lens barrel, a second lens barrel, and a third lens barrel, wherein the first lens is placed inside the first lens barrel, the second lens is placed inside the second lens barrel, and the third lens is placed inside the third lens barrel; Wherein, the position of the first lens relative to the image plane on the second side on the optical axis is fixed, and the distance of the second lens relative to the first lens on the optical axis is adjustable; The visual system has three lenses with optical power; The visual system satisfies: 1.0 <f2 / (dbs+dbm)<1.3,2.8<Lac / ΔL<3.6, Wherein, f2 is the effective focal length of the second lens, dbs is the inner diameter of the first side end face of the second lens barrel, dbm is the inner diameter of the second side end face of the second lens barrel, Lac is the distance between the second side end face of the first lens barrel and the first side end face of the third lens barrel along the optical axis, and ΔL is the movable distance of the second lens when the visual system switches between the first state and the second state.

2. The visual system according to claim 1, characterized in that, The visual system also satisfies: 3.90≤(Das-das) / La≤5.74 Wherein, das is the inner diameter of the first side end face of the first lens barrel, Das is the outer diameter of the first side end face of the first lens barrel, and La is the distance between the first side end face and the second side end face of the first lens barrel along the optical axis.

3. The visual system according to claim 1, characterized in that, The visual system also satisfies: 1.29≤fg / (dam+Dam)≤1.55 Wherein, fg is the combined focal length of the first lens, the reflective polarizing element and the quarter-wave plate, dam is the inner diameter of the second side end face of the first lens barrel, and Dam is the outer diameter of the second side end face of the first lens barrel.

4. The visual system according to claim 1, characterized in that, The visual system also satisfies: 1.45≤(CT1+CTR+CTQ) / La≤1.81, Wherein, CT1 is the center thickness of the first lens on the optical axis, CTR is the center thickness of the reflective polarizing element on the optical axis, CTQ is the center thickness of the quarter-wave plate on the optical axis, and La is the distance between the first side end face and the second side end face of the first lens barrel along the optical axis.

5. The visual system according to claim 1, characterized in that, The visual system also satisfies: 3.45 <CT2 / |Dbs-Dbm|<5.0, Wherein, CT2 is the center thickness of the second lens on the optical axis, Dbs is the outer diameter of the first side end face of the second lens barrel, and Dbm is the outer diameter of the second side end face of the second lens barrel.

6. The visual system according to claim 1, characterized in that, The visual system also satisfies: 1.85 <R1 / das<2.25, Wherein, R1 is the radius of curvature of the first side surface of the first lens, and das is the inner diameter of the first side end face of the first lens barrel.

7. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: 8.25 <dcs / CT3<12.55, Wherein, dcs is the inner diameter of the first side end face of the third lens barrel, and CT3 is the center thickness of the third lens on the optical axis.

8. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: 2.9 <Lb / Δf<3.85, Wherein, Lb is the distance between the first side end face and the second side end face of the second lens barrel along the optical axis, and Δf is the difference between the total effective focal length of the visual system in the first state and the total effective focal length of the visual system in the second state.

9. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: 2.5 <f1 / Das<3.1, Where f1 is the effective focal length of the first lens, and Das is the outer diameter of the first side end face of the first lens barrel.

10. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: 1.1 <Lc / |Dcs-Dcm|<2.5, Wherein, Lc is the distance between the first side end face and the second side end face of the third lens barrel along the optical axis, Dcs is the outer diameter of the first side end face of the third lens barrel, and Dcm is the outer diameter of the second side end face of the third lens barrel.

11. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: -1.55 <R4 / dbm<-1.15, Wherein, R4 is the radius of curvature of the second side surface of the second lens, and dbm is the inner diameter of the second side end face of the second lens barrel.

12. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: 1.65≤f3 / (dcm+Dcm)≤3.09 Where f3 is the effective focal length of the third lens, dcm is the inner diameter of the second side end face of the third lens barrel, and Dcm is the outer diameter of the second side end face of the third lens barrel.

13. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: 2.15 <TD / Lac<2.5, Wherein, TD is the axial distance from the first side surface of the first lens to the second side surface of the third lens, and Lac is the distance along the optical axis between the second side end face of the first lens barrel and the first side end face of the third lens barrel.

14. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: 1.45 < (La + Lc) / Lb < 2.9 Wherein, La is the distance between the first side end face and the second side end face of the first lens barrel along the optical axis, Lb is the distance between the first side end face and the second side end face of the second lens barrel along the optical axis, and Lc is the distance between the first side end face and the second side end face of the third lens barrel along the optical axis.

15. The visual system according to any one of claims 1 to 6, characterized in that, The visual system also satisfies: 1.55≤(Das+Dcs) / Dbs≤1.89, Wherein, Das is the outer diameter of the first side end face of the first lens barrel, Dbs is the outer diameter of the first side end face of the second lens barrel, and Dcs is the outer diameter of the first side end face of the third lens barrel.

Images