Head-mounted device and optical system thereof

Abstract

The invention provides a head-mounted device and an optical system thereof, the optical system of the head-mounted device comprises a lens barrel, a lens group and a spacing element, and the lens group comprises a reflective polarizing element, a quarter-wave plate, a first lens, a second lens and a third lens. The reflective polarizing element, the quarter-wave plate and the first lens form an optical element group, the spacing elements comprise a first spacing element and a second spacing element, the first spacing element is located between the first lens and the second lens, and the optical system meets the following conditions: 0.9 lt; l / flt; 1.4 lt and 1.4 lt; d1m / F1lt; f is the effective focal length of the optical system, L is the maximum horizontal distance from the object side surface of the lens barrel to the image side surface of the lens barrel in the optical axis direction, F1 is the focal length of the optical element group, and d1m is the inner diameter of the plane, perpendicular to the optical axis, of the image side surface of the spacing element.

Description

Technical Field

[0001] The present invention relates to the field of optical systems, and in particular to a head-mounted device and an optical system thereof. Background Art

[0002] In recent years, with the rapid development of virtual reality (VR) and augmented reality (AR) technologies, their wide application in gaming, education and other industries has led to an increasing demand for head-mounted devices. However, existing head-mounted device optical systems still have some problems in terms of image quality, field of view, size, etc. For example, the external field of view is blurred, the image quality needs to be improved, and the large size of the lens barrel affects wearing comfort.

[0003] The continuous development of hardware technology is one of the key factors driving VR / AR technology to maturity. With the continuous improvement of processor performance, VR / AR devices can run complex graphics and computing tasks more smoothly, providing users with more realistic visual effects. The advancement of display technology also makes the images of VR / AR devices clearer, more delicate, and more colorful. At the same time, the development of sensor technology enables VR / AR devices to more accurately capture the user's movements and position information, achieving a more natural interactive experience.

[0004] Among them, the design of VR / AR lenses using the optical path deflection scheme is an important technological innovation. Traditional VR / AR lenses are usually large in size, heavy in weight, and not comfortable to wear. However, through the optical path deflection scheme, the length of the lens body can be compressed to half of the original, so that the center of gravity of the head-mounted device is moved backward, greatly reducing the burden on the user's head and optimizing the consumer experience. This design not only makes the device lighter, but also improves the stability of the device and the comfort of wearing.

[0005] At present, devices based on optical path deflection have been released and have attracted widespread attention in the market. However, from the actual experience of users, these devices still have some shortcomings. Among them, the blurry external field of view is a more prominent problem. This is mainly due to certain limitations in the design of the optical path deflection solution, which leads to unstable light transmission in the external field of view, thus affecting the clarity of the picture. In addition, the imaging quality of the 2-piece lens needs to be improved. Although the 2-piece lens can meet the basic needs of users to a certain extent, there are still some shortcomings in terms of image contrast, color reproduction and other aspects.

[0006] An important reason for these problems is that they were previously limited by film-sticking technology. In the manufacturing process of VR / AR lenses, film-sticking technology is a key process. However, due to technical limitations, the accuracy and quality of the film are difficult to guarantee, which affects the performance of the lens. In addition, due to the limitations of film-sticking technology, the lenses in the solution have fewer degrees of freedom and cannot give full play to the performance of the optical system. This also leads to the need to improve system performance and fail to provide users with a better visual experience.

[0007] In order to solve these problems, researchers and engineers are constantly innovating and improving technology. On the one hand, they are committed to improving the accuracy and quality of film laminating technology, and ensuring that the performance of the lens is fully utilized by adopting more advanced film laminating equipment and processes. On the other hand, they are also exploring new lens design solutions to increase the freedom of the lens and improve the performance of the optical system. At the same time, they are also constantly optimizing the performance of hardware equipment, improving the computing speed of the processor, the clarity of the display technology and the accuracy of the sensor, to provide users with a smoother and more realistic visual experience. Summary of the invention

[0008] A major advantage of the present invention is that it provides a head-mounted device and an optical system thereof, wherein the optical system of the head-mounted device is based on a three-lens architecture and combined with a curved surface film technology, thereby further shortening the thickness of the head-mounted device.

[0009] Another advantage of the present invention is to provide a head-mounted device and an optical system thereof, wherein the optical system of the head-mounted device improves system performance and enhances the visual experience of consumers.

[0010] Another advantage of the present invention is to provide a head mounted device and an optical system thereof, wherein the optical system of the head mounted device improves market competitiveness by controlling the size of some structures and the module cost.

[0011] Another advantage of the present invention is that it provides a head-mounted device and an optical system thereof, wherein the optical system can effectively constrain the field of view of the system by controlling the focal length of the optical imaging system, so that the system meets the characteristics of a large field of view of a VR lens.

[0012] Another advantage of the present invention is to provide a head mounted device and an optical system thereof, wherein the outer dimensions of the lens barrel are constrained, so that the outer dimensions of the lens barrel are minimized while ensuring the machinability of the lens barrel, thereby reducing the size of the entire device.

[0013] Another advantage of the present invention is that it provides a head-mounted device and an optical system thereof, wherein by controlling the effective focal length of the first lens, it is beneficial to control the shape of the first lens, thereby determining a position that is beneficial to the attachment of the RP film; and by controlling the distance from the object side end face of the lens barrel to the first spacing element, the wall thickness of the front end face of the lens barrel and the structural diameter thickness of the first spacing element are controlled, which is beneficial to the molding of the lens barrel and the lens; it is also beneficial to control the size of components.

[0014] Another advantage of the present invention is that it provides a head-mounted device and an optical system thereof, wherein the shape of the first lens is effectively controlled by a specific relationship, reducing the difficulty of molding the first lens, and at the same time controlling the spacing between the two spacing elements, which is beneficial to reducing the height of the main body. In addition, the inner diameter of the object side end of the first spacing element is controlled, both of which are beneficial to the miniaturization of VR lenses.

[0015] Another advantage of the present invention is that it provides a head-mounted device and an optical system thereof, wherein the middle thickness of the first lens is controlled by a specific relationship, which is beneficial to controlling the shape of the first lens, thereby determining a position that is beneficial to the attachment of the RP film; by controlling the distance from the object side end face of the lens barrel to the first spacing element, the wall thickness of the front end face of the lens barrel and the structural diameter thickness of the first spacing element are controlled, which is beneficial to the molding of the lens barrel and the lens; it also helps to constrain the overall size of the spacing element and the lens.

[0016] Another advantage of the present invention is to provide a head mounted device and an optical system thereof, wherein a specific relationship is used to ensure that the relative position between the lens barrel and the spacing element is reasonable, thereby avoiding conflicts or waste in space. This is essential for realizing a compact and efficient optical system. In addition, by optimizing the positional relationship between the lens barrel and the spacing element, the performance of the optical system can be improved without increasing excessive costs. In addition, a reasonable layout also helps to reduce material consumption and manufacturing costs.

[0017] Another advantage of the present invention is to provide a head-mounted device and an optical system thereof, wherein the compactness of the optical system is ensured by a specific relationship, and aberrations such as spherical aberration, coma, astigmatism, etc. can be reduced by optimizing the ratio of parameters, thereby improving the clarity and resolution of imaging.

[0018] Another advantage of the present invention is to provide a head mounted device and an optical system thereof, wherein specific relationships are used to help properly arrange optical components while maintaining the compactness of the system.

[0019] Another advantage of the present invention is to provide a head mounted device and an optical system thereof, wherein the ratio of the inner diameter of the lens barrel to the effective radius of the lens can be adjusted through a specific relationship, so as to control spherical aberration, coma, astigmatism, field curvature and distortion to a certain extent.

[0020] Another advantage of the present invention lies in providing a head-mounted device and its optical system, wherein the ratio between the inner diameter of the spacer element and the SAG value of the image side of the second lens is adjusted through a specific relational expression, optimizing the field of view angle to a certain extent; through reasonable adjustment, the relationship between the system size and performance can be balanced to a certain extent. While ensuring good imaging quality, the size and weight of the system are minimized as much as possible to improve wearing comfort and portability.

[0021] Another advantage of the present invention lies in providing a head-mounted device and its optical system, wherein the ratio between the difference in the inner diameters of the object side and the image side of the lens barrel and the focal length is adjusted through a specific relational expression, which can affect the light propagation path and the imaging characteristics of the system, thereby optimizing the imaging quality to a certain extent. Through reasonable adjustment, the size of the system can be minimized as much as possible on the premise of ensuring performance.

[0022] Another advantage of the present invention lies in providing a head-mounted device and its optical system, wherein the relative sizes and intervals between the spacer element and the lens are adjusted through a specific relational expression, which can control the optical path length, thereby optimizing the imaging quality. Through the set ratio relationship, the manufacturing cost can be reduced as much as possible on the premise that the system performance meets the requirements.

[0023] Another advantage of the present invention lies in providing a head-mounted device and its optical system, wherein the sizes of some components in the system can be minimized as much as possible on the premise of ensuring the system performance. Through the set ratio range, clear guidance can be provided for the manufacturing and assembly processes, thereby improving the manufacturing and assembly accuracy of the system and helping to reduce the performance degradation caused by manufacturing and assembly errors.

[0024] According to one aspect of the present invention, an optical system of a head-mounted device of the present invention capable of achieving the foregoing and other objects and advantages includes:

[0025] A lens barrel;

[0026] A lens group, wherein the lens group includes a reflective polarizing element, a quarter-wave plate, a first lens, a second lens, and a third lens. Among them, the reflective polarizing element, the quarter-wave plate, and the first lens form an optical element group, and the optical element group has a positive optical power. The second lens has a positive optical power, the third lens has an optical power, and the image sides of the second lens and the third lens are convex. The optical system satisfies the following conditions: 0.9 < L / f < 1.4 and 1.4 < d1m / F1 < 2.3, where f is the effective focal length of the optical system, L is the maximum horizontal distance along the optical axis from the object side of the lens barrel to the image side of the lens barrel, F1 is the focal length of the optical element group, and d1m is the inner diameter of the plane perpendicular to the optical axis of the image side of the spacer element.

[0027] According to an embodiment of the present invention, the optical system further includes a spacer element, wherein the spacer element includes a first spacer element and a second spacer element. The first spacer element is located between the first lens and the second lens and abuts against the second side surface of the first lens. The second spacer element is disposed between the second lens and the third lens. The optical system of the head-mounted device further satisfies the following condition: 0.30 < EP12 / (d1s - 2*DT11) < 2.55, where EP12 is the axial spacing distance between the image side surface of the first spacer element and the object side surface of the second spacer element, d1s is the inner diameter of the plane perpendicular to the optical axis of the object side surface of the spacer element, and DT11 is the maximum effective radius of the object side surface of the first lens.

[0028] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 2.0 < (D1s - d1m) / |SAG11| ≤ 12.6, where d1m is the inner diameter of the plane perpendicular to the optical axis of the image side surface of the first spacer element, D1s is the outer diameter of the plane perpendicular to the optical axis of the object side surface of the first spacer element, and SAG11 is the axial distance between the intersection point of the object side surface of the first lens and the optical axis and the vertex of the effective radius of the object side surface of the first lens.

[0029] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 0.80 < EP01 / CT1 < 1.25, where EP01 is the axial spacing distance between the object side end face of the lens barrel and the object side surface of the first spacer element, and CT1 is the central thickness of the first lens on the optical axis.

[0030] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 1.4 ≤ L / EP02 < 1.7, where L is the maximum horizontal distance along the optical axis between the object side end face of the lens barrel and the image side end face of the lens barrel, and EP02 is the axial spacing distance between the object side end face of the lens barrel and the object side surface of the second spacer element.

[0031] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 0.15 < CP1 / (CT1 + T12) < 0.80, where CP1 is the maximum thickness of the first spacer element along the optical axis, CT1 is the central thickness of the first lens on the optical axis, and T12 is the air gap between the first lens and the second lens on the optical axis.

[0032] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 1.4 < CP2 / T23 < 6.2, where CP2 is the maximum thickness of the second spacer element along the optical axis direction, and T23 is the air gap between the second lens and the third lens on the optical axis.

[0033] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 2.05 < d0m / DT32 < 3.30, where d0m is the inner diameter of the plane perpendicular to the optical axis on the image side of the barrel, and DT32 is the maximum effective radius of the image side of the third lens.

[0034] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 35.05 < d2m / |SAG22| < 59.35, where d2m is the inner diameter of the plane perpendicular to the optical axis on the image side of the second spacer element, and SAG22 is the axial distance between the intersection of the image side of the second lens and the optical axis and the vertex of the effective radius of the image side of the second lens.

[0035] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 0.20 < (d0m - d0s) / f < 1.30, where d0s is the inner diameter of the plane perpendicular to the optical axis on the object side of the barrel, and d0m is the inner diameter of the plane perpendicular to the optical axis on the image side of the barrel.

[0036] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 0.95 < d1m / (DT12*2) < 1.20, where d1m is the inner diameter of the plane perpendicular to the optical axis on the image side of the first spacer element, and DT12 is the maximum effective radius of the image side of the first lens.

[0037] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 0.95 < (CP1 + E12 + CP2) / (T12 + CT2 + T23) < 2.80, where CP1 is the maximum thickness of the first spacer element along the optical axis direction, CP2 is the maximum thickness of the second spacer element along the optical axis direction, T12 is the air gap between the first lens and the second lens on the optical axis, T23 is the air gap between the second lens and the third lens on the optical axis, and CT2 is the central thickness of the second lens on the optical axis.

[0038] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: -4.85 < f23 / R5 * (CP2 / T23) < 9.3, where f23 is the combined focal length of the second lens and the third lens, R5 is the radius of curvature of the object side surface of the third lens, and T23 is the air gap between the second lens and the third lens on the optical axis.

[0039] According to an embodiment of the present invention, the optical system of the head-mounted device further satisfies the following condition: 0.05 < CP2 / |SAG31| < 0.30, where SAG31 is the axial distance between the intersection of the object side surface of the third lens and the optical axis and the vertex of the effective radius of the object side surface of the third lens.

[0040] On the other hand, according to the present application, the present application further provides a head-mounted device, including:

[0041] A head-mounted device body; and

[0042] At least one optical system as described in any one of the above, wherein the optical system is mounted on the head-mounted device body.

[0043] Through the understanding of the subsequent description and the drawings, the further objects and advantages of the present invention will be fully reflected.

[0044] These and other objects, features, and advantages of the present invention are fully reflected through the following detailed description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Hereinafter, the technical solutions of the present invention will be further described in detail in conjunction with the drawings and embodiments. In the drawings, unless otherwise specified, the same reference numerals are used to represent the same components. Among them:

[0046] Figure 1 It is a schematic structural diagram of the optical system of the head-mounted device according to the first preferred embodiment of the present invention.

[0047] Figure 2 It is a schematic structural diagram of the optical system of the head-mounted device according to the second preferred embodiment of the present invention.

[0048] Figure 3 It is a schematic structural diagram of the optical system of the head-mounted device according to the third preferred embodiment of the present invention.

[0049] Figure 4 It is a schematic structural diagram of the optical system of the head-mounted device according to the fourth preferred embodiment of the present invention.

[0050] Figure 5 It is a schematic structural diagram of the optical system of the head-mounted device according to the fifth preferred embodiment of the present invention.

[0051] Figure 6 4 is a schematic diagram of the structure of the optical system of the head-mounted device according to the sixth preferred embodiment of the present invention.

[0052] Figure 7 4 is a schematic diagram of the structure of the optical system of the head-mounted device according to the seventh preferred embodiment of the present invention.

[0053] Figure 8 2 is a schematic structural diagram of an optical system of a head mounted device according to an eighth preferred embodiment of the present invention.

[0054] Fig. 9 4 is a schematic diagram of the structure of the optical system of the head-mounted device according to the ninth preferred embodiment of the present invention.

[0055] FIG. 10A to FIG. 10C Schematic diagram of an axial chromatic aberration curve, an astigmatism curve and a distortion curve of the optical system of the head mounted device according to the first to third preferred embodiments of the present invention.

[0056] FIG. 11A to FIG. 11C Schematic diagram of an axial chromatic aberration curve, an astigmatism curve and a distortion curve of the optical system of the head mounted device according to the fourth to sixth preferred embodiments of the present invention.

[0057] FIG. 12A to FIG. 12C Schematic diagram of an axial chromatic aberration curve, an astigmatism curve and a distortion curve of the optical system of the head mounted device according to the seventh to ninth preferred embodiments of the present invention.

[0058] Fig.13 Schematic diagram of the dimensions of the optical system of the head mounted device according to the first preferred embodiment of the present invention.

[0059] Fig.14 Schematic diagram of the dimensions of the first lens of the optical system of the head mounted device according to the first preferred embodiment of the present invention. DETAILED DESCRIPTION

[0060] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0061] Those skilled in the art should understand that, in the disclosure of the present invention, the orientation or positional relationship indicated by terms such as longitudinal, transverse, up, down, front, back, left, right, vertical, horizontal, top, bottom, inside, outside, etc. is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0062] It is understandable that the term one should be understood as at least one or one or more, that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term one should not be understood as a limitation on the quantity.

[0063] Referring to the drawings of this application specification Figures 1 to 14 As shown, an optical system of a head-mounted device according to one aspect of the present application is explained in the following description. The optical system of the head-mounted device includes the lens barrel P0 and a lens group E assembled in the lens barrel P0 and at least one spacing element P. The lens group E includes a reflective polarizing element S1, a quarter wave plate S2, a first lens E1, a second lens E2 and a third lens E3, wherein the at least one spacing element P is arranged at intervals between the first lens E1, the second lens E2 and the third lens E3. The optical system of the head-mounted device has an object side end and an image side end, wherein the reflective polarizing element S1, the quarter wave plate S2, the first lens E1, the second lens E2 and the third lens E3 of the lens group E are arranged in sequence from the object side end (first side) of the lens barrel P0 to the image side end (second side).

[0064] Among them, the reflective polarizing element S1, the quarter wave plate S2, and the first lens E1 constitute an optical element group E0, and the optical element group E0 has positive focal length. Positive focal length means that the optical element group E0 can converge light, thereby playing an important role in the imaging process. It should be noted that in this preferred embodiment of the present application, the reflective polarizing element S1 can selectively reflect or transmit light in a specific polarization direction, thereby improving the contrast and color saturation of the image. The quarter wave plate S2 can convert linearly polarized light into circularly polarized light or vice versa, further enhancing the performance of the optical system. The shape and parameters of the first lens E1 directly affect the imaging quality of the entire optical system.

[0065] Preferably, in this preferred embodiment of the present application, the reflective polarizing element S1 and the quarter-wave plate S2 are attached to the object-side end of the first lens E1, that is, the reflective polarizing element S1, the quarter-wave plate S2, and the first lens E1 are combined to form the optical element group E0.

[0066] The reflective polarizing element S1 and the quarter wave plate S2 of the optical element group E0 are located on the object side of the first lens E1, wherein the reflective polarizing element S1 can be used as the first object side surface of the optical element group E0, and the quarter wave plate S2 is used as the second object side surface of the optical element group E0. Further, the first lens E1 has a first lens object side surface S3 facing the object side and a first lens image side surface S4 facing the image side, the second lens E2 has a second lens object side surface S5 facing the object side and a second lens image side surface S6 facing the image side, and the third lens E3 has a third lens object side surface S7 facing the object side and a third lens image side surface S8 facing the image side.

[0067] The second lens E2 has optical power, and its image side surface (i.e., the image side surface S6 of the second lens) is a convex surface, which can make the light more concentrated when passing through the second lens E2, thereby improving the clarity and brightness of the image. The convex image side surface can better collect and focus the light, making the image sharper.

[0068] The third lens E3 also has optical power, and its image side surface (i.e., the image side surface S8 of the third lens) is also convex. Similar to the second lens E2, the convex image side surface of the third lens E3 can effectively collect light and improve the image quality. In addition, the optical power of the third lens E3 can cooperate with the first lens E1 and the second lens E2 to jointly adjust the focal length and field of view of the optical system to meet different application requirements.

[0069] The spacer element P further includes a first spacer element P1 and a second spacer element P2, wherein the first spacer element P1 is located between the first lens E1 and the second lens E2 and abuts against the second side surface of the first lens E1. The second spacer element P2 is disposed between the second lens E2 and the third lens E3.

[0070] It is worth mentioning that the function of the spacer element P is to keep the distance between the lenses stable and prevent collision and friction between the lenses, thereby ensuring the stability and reliability of the optical system.

[0071] The lens barrel P0 has an object side end surface P01 and an image side end surface P02 , wherein the object side end surface P01 is located at the object side end of the lens barrel P0 , and the image side end surface P02 is located at the image side end of the lens barrel P0 .

[0072] To ensure the performance of the optical system, the following conditions need to be met: 0.9 < L / f < 1.4. Here, f is the effective focal length of the optical system, and L is the maximum horizontal distance along the optical axis from the object side surface P01 to the image side surface P02 of the lens barrel P0. It can be understood that this technical condition of the optical system can effectively control the focal length of the optical system, thereby restricting the field of view angle of the system and enabling the system to meet the characteristics of a large field of view of a VR lens. A large field of view allows users to obtain a broader field of view when wearing the head-mounted device, enhancing the immersion feeling.

[0073] Furthermore, the optical system further meets the following condition: 1.4 < d1m / F1 < 2.3, where F1 is the focal length of the optical element group E0, and d1m is the inner diameter of the plane perpendicular to the optical axis of the image side surface of the spacer element P1. It is worth mentioning that when d1m / F1 is less than 1.4, a series of problems will occur. First, the length of the lens barrel P0 is short, resulting in an insufficient propagation path of light in the lens barrel P0. This will make it easy for light to be blurred or distorted during the imaging process, affecting the image quality. To compensate for this problem, more complex optical elements need to be used for compensation. However, this will increase the cost and structural complexity, which is not conducive to the large-scale production and application of the head-mounted device; when d1m / F1 is greater than 2.3, adverse effects will also be generated. A larger d1m means that light may spread to the edge area when passing through P1, and these areas may not be effectively utilized or collected. In this way, the light reaching the image plane will be reduced, thereby affecting the imaging brightness. In addition, a larger ratio of d1m to F1 may also lead to an increase in aberration. Light is more susceptible to various aberrations when passing through a larger aperture, such as spherical aberration, coma aberration, astigmatism, etc. These aberrations will reduce the imaging quality, making the image blurred and distorted. Moreover, an overly large d1m may mean design redundancy, increasing the volume, weight, and cost of the system without bringing substantial performance improvement.

[0074] It is worth mentioning that when the optical system satisfies the above relational expressions, the following several effects can be achieved: First, the focal length of the optical system can be effectively controlled, the field of view angle of the system is constrained, and the system meets the characteristics of a large field of view of a VR lens. A large field of view can bring a more immersive experience to users, making them feel as if they are in a virtual world. Second, by constraining the outer dimensions of the barrel P0, on the premise of ensuring the machinability of the barrel P0, the outer dimensions of the barrel P0 are made as small as possible, thereby reducing the overall size of the machine. This is very important for a head-mounted device because a smaller size can improve the wearing comfort and portability. Third, by controlling the effective focal length of the first lens E1, it is beneficial to control the shape of the first lens E1, thereby determining the position conducive to the attachment of the RP film (reflection type polarization film, i.e., the reflection type polarizing element S1). The attachment of the RP film can further improve the performance of the optical system, such as reducing reflection and increasing contrast. Finally, by controlling the distance from the object side end face of the barrel P0 to the spacer element P1, the wall thickness of the front end face of the barrel P0 and the mechanism diameter thickness of the spacer element P1 can be controlled. This is beneficial to the forming of the barrel P0 and the lens, improving production efficiency and quality. At the same time, it is also beneficial to control the size of the components and reduce costs.

[0075] It can be understood that through reasonable design and parameter control, the optical system of the head-mounted device in this preferred embodiment of the present application achieves excellent performance and effects. It not only meets the requirements of a large field of view of a VR lens, but also reduces the overall size of the machine on the premise of ensuring the imaging quality, improving the wearing comfort and portability.

[0076] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 0.30 < EP12 / (d1s - 2*DT11) < 2.55, where EP12 is the interval distance between the image side of the first spacer element P1 and the object side of the second spacer element P2 in the optical axis direction, d1s is the inner diameter of the plane perpendicular to the optical axis of the object side of the spacer element P1, and DT11 is the maximum effective radius of the object side S3 of the first lens. It is worth mentioning that in this preferred embodiment of the present application, the setting of the above technical condition parameter range can effectively control the shape of the first lens E1 and reduce the forming difficulty. At the same time, it can also control the interval between the first spacer element P1 and the second spacer element P2, which is beneficial to reducing the body height and realizing the miniaturization of the VR lens.

[0077] In other words, this preferred embodiment of the present application can effectively control the shape of the first lens E1 and reduce its molding difficulty by reasonably setting the maximum effective radius of the object side S3 of the first lens, the spacing distance between the first spacing element P1 and the second spacing element P2, which is of great significance for improving production efficiency and reducing costs. In addition, it can be understood that by controlling the spacing between the two spacing elements, the main body height of the optical system can be reduced, which is very important for head-mounted devices because it can make the device lighter, more comfortable, and more convenient to wear. In addition, this preferred embodiment of the present application can further reduce the size of the optical system by controlling the inner diameter of the object side end of the first spacing element P1, which is conducive to the miniaturization of VR lenses, making the device more portable and convenient for users to carry and use.

[0078] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 2.0<(D1s-d1m) / |SAG11|≤12.6, wherein d1m represents the inner diameter of the plane of the first spacer element P1 perpendicular to the optical axis, which determines the range of light that can enter the optical system through the first spacer element P1. A smaller inner diameter can limit the entry of too much light and prevent overexposure caused by excessive light flux; while a larger inner diameter may allow more light to enter the system, which requires careful adjustment to avoid underexposure caused by insufficient light flux. D1s is the outer diameter of the plane of the first spacer element P1 perpendicular to the optical axis. It can be understood that this outer diameter size together with the inner diameter defines the overall size of the first spacer element P1. A larger outer diameter can provide more space for the optical system to arrange other components, but it may also increase the size of the entire machine and affect the portability of the device. Therefore, it is necessary to reasonably control the size of the outer diameter while ensuring the optical performance. SAG11 is the on-axis distance between the intersection of the first lens object side S3 and the optical axis to the effective radius vertex of the first lens object side S3. This distance reflects the shape and curvature of the first lens and plays an important role in the refraction and focusing of light. Therefore, by adjusting the value of SAG11, the optical performance of the first lens E1 can be changed, thereby affecting the imaging quality of the entire optical system.

[0079] It is worth mentioning that in this preferred embodiment of the present application, the ratio of (D1s-d1m) / |SAG11| in the above relationship reflects the relationship between the size of the first spacing element P1 and the shape of the first lens E1. When this ratio varies between 2.0 and 12.6, it means that the size of the first spacing element P1 and the shape of the first lens E1 can be adjusted within a certain range to meet different optical design requirements. For example, when a larger field of view is required, the values ​​of D1s and d1m can be appropriately increased, while the value of SAG11 can be reduced to increase the incident angle and range of light. When a higher resolution is required, the values ​​of D1s and d1m can be reduced, while the value of SAG11 can be increased to improve the focusing accuracy and imaging quality of light.

[0080] First, in the above relationship of the preferred embodiment of the present application, d1m limits the amount of light that can enter the optical system. Under different lighting conditions, by adjusting the value of d1m, it is possible to ensure that the optical system receives the appropriate amount of light and avoid overexposure or underexposure. For example, in a strong light environment, the value of d1m can be reduced to reduce the amount of light entering the system and prevent the image from being too bright; while in a weak light environment, the value of d1m can be appropriately increased to increase the collection of light and improve the brightness of the image. Therefore, this control of the light flux can improve the quality and stability of the image, so that the head-mounted device can provide clear and accurate images in different environments. Secondly, in the above relationship of the preferred embodiment of the present application, although D1s does not directly affect the light flux, it defines the overall size of the first spacing element P1 together with d1m. Reasonable control of the values ​​of D1s and d1m can make the size of the first spacing element P1 match other optical elements and the overall structure, thereby helping to constrain the size of the overall machine and improve the compactness of the system. For head-mounted devices, a compact design can make the device lighter, more comfortable, and more convenient to wear. At the same time, the smaller size is also conducive to the carrying and storage of the device, improving the user experience.

[0081] In addition, in the above-mentioned relationship of the preferred embodiment of the present application, the optical system of the head-mounted device allows (D1s-d1m) / |SAG11| to vary within a certain range, which provides great flexibility for optical design. Designers can adjust the size and position of the spacer elements and lenses according to specific needs, such as focal length, field of view, aperture size, etc., to achieve optimal optical performance. For example, when the focal length needs to be adjusted, it can be achieved by changing the curvature of the first lens E1 and the position of the first spacer element P1. When the field of view needs to be changed, the values ​​of D1s and d1m can be adjusted to change the incident angle and range of the light. This flexibility enables the optical system to adapt to different application scenarios and user needs, improving the versatility and competitiveness of the product.

[0082] Therefore, when the optical system of the head-mounted device in the preferred embodiment of the present application satisfies the following relational expression: 2.0 < (D1s - d1m) / |SAG11| ≤ 12.6, by controlling the size of the first spacer element P1 and the shape of the first lens, the control of the light flux, the constraint of the overall size of the device, and the flexibility of the optical design are achieved, facilitating the provision of high-quality images and a comfortable user experience.

[0083] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 0.80 < EP01 / CT1 < 1.25, where EP01 is the distance between the object-side end face P01 of the lens barrel and the object side surface of the first spacer element P1 along the optical axis direction, and CT1 is the central thickness of the first lens E1 on the optical axis.

[0084] It is worth mentioning that EP01 not only affects the structural layout at the front end of the lens barrel but is also closely related to the optical performance. An appropriate value of EP01 can ensure that light rays can propagate at the optimal angle and path when entering the optical system, improving the imaging quality. Specifically, the size of EP01 affects the wall thickness of the front end face of the lens barrel. If EP01 is too small, the wall thickness of the front end face of the lens barrel may be insufficient, resulting in a reduction in the strength and stability of the lens barrel. On the contrary, if EP01 is too large, the wall thickness of the front end face of the lens barrel may be too large, increasing the weight and volume of the lens barrel, which is not conducive to the miniaturization and lightweight design of the device.

[0085] It is worth mentioning that the change in the central thickness of the first lens E1 will cause changes in the curvature and surface shape of the first lens. Therefore, by controlling CT1, the shape of the first lens E1 can be precisely adjusted to meet different optical design requirements.

[0086] When the value of CT1 increases, the central part of the first lens E1 becomes thicker, thereby changing the curvature of the lens. This change can affect the refraction and focusing of light rays, and thus adjust the imaging effect of the optical system. It can be understood that in the preferred embodiment of the present application, by adjusting the value of CT1, the surface shape of the first lens E1 can be made smoother and more regular, providing a good basis for the attachment of the RP film. This can not only improve the adhesion firmness of the RP film but also ensure the stable and reliable optical performance of the optical system.

[0087] By controlling the distance EP01 from the object-side end face P01 of the lens barrel to the spacer element P1, the wall thickness of the front end face of the lens barrel and the structural radial thickness of the first spacer element P1 can be effectively controlled. During the molding process of the lens barrel P0, an appropriate wall thickness of the front end face can ensure that the lens barrel has sufficient strength and rigidity to withstand the pressure of internal optical elements and external impacts. At the same time, a reasonable structural radial thickness of the first spacer element P1 can ensure that the spacer element can be stably installed in the lens barrel, providing reliable support and separation for the lens group. For example, by adjusting the value of EP01, the wall thickness of the front end face of the lens barrel and the structural radial thickness of the first spacer element P1 can reach the optimal state, thereby improving the molding quality of the lens barrel and the lens. This can reduce defects and scrap rates during the production process and lower production costs.

[0088] In this preferred embodiment of the present application, by controlling the ratio of EP01 to CT1, it helps to constrain the overall dimensions of the first spacer element P1 and the lens. That is, by reasonably adjusting these two parameters, the optical system can be made more compact, reducing the volume and weight of the device and improving the portability and usability of the device.

[0089] As an example, in a specific example of the present application, by optimizing the values of EP01 and CT1, the dimensions of the lens barrel and the lens can be made smaller and more compact, thus meeting the requirements of different application scenarios. In some occasions with high space requirements, such as head-mounted display devices, micro cameras, etc., a miniaturized optical system can provide a better user experience.

[0090] When the optical system of the head-mounted device in this preferred embodiment of the present application satisfies: 0.80 < EP01 / CT1 < 1.25, that is, by controlling the central thickness CT1 of the first lens E1 and the distance EP01 from the object-side end face P01 of the lens barrel to the spacer element P1, precise control of the shape of the first lens E1 can be achieved, determining a position favorable for RP film attachment; at the same time, the wall thickness of the front end face of the lens barrel and the structural radial thickness of the spacer element P1 can also be controlled, which is beneficial to the molding of the lens barrel and the lens; in addition, the overall dimensions of the spacer element and the lens can be constrained, realizing the miniaturization and lightweight design of the optical system.

[0091] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 1.4 ≤ L / EP02 < 1.7, where L is the maximum horizontal distance along the optical axis from the object-side end face P01 of the lens barrel to the image-side end face P02 of the lens barrel, and EP02 is the spacer distance along the optical axis from the object-side end face P01 of the lens barrel to the object side face of the second spacer element P2.

[0092] It is worth mentioning that by restricting the ratio between L and EP02 within the range of 1.4 ≤ L / EP02 < 1.7, the relative position between the lens barrel P0 and the second spacer element P2 can be ensured to be reasonable. That is to say, when designing the optical system, the distance between the lens barrel and the spacer element can be precisely controlled to avoid spatial conflicts or waste. For example, if the ratio of L to EP02 is too large, it may lead to an overly long distance between the lens barrel and the spacer element, wasting space and increasing the volume of the optical system; while if the ratio is too small, the distance between the lens barrel and the spacer element may be too short, causing obstruction to the light propagation and affecting the imaging quality. Therefore, by precisely controlling the distance between the lens barrel and the spacer element, the optimal optical performance can be achieved within a limited space, meeting the high requirements of users for optical devices.

[0093] In addition, by reasonably adjusting the ratio of L to EP02, the light can propagate more smoothly in the optical system, reducing light scattering and loss, and improving the clarity and contrast of the image. Furthermore, the performance indicators such as the field of view angle and focal length of the optical system can be optimized to meet the requirements of different application scenarios. By optimizing the positional relationship between the lens barrel and the spacer element, the volume and weight of the optical system can be minimized as much as possible on the premise of meeting the optical performance requirements, thereby reducing the material usage. When mass-producing optical devices, by precisely controlling the ratio of L to EP02, standardized production can be achieved, improving production efficiency and reducing production costs. At the same time, the scrap rate can also be reduced, improving the quality and reliability of the product.

[0094] When the optical system of the head-mounted device in the preferred embodiment of the present application satisfies the technical feature of 1.4 ≤ L / EP02 < 1.7, by restricting the ratio between L and EP02, the relative position between the lens barrel P0 and the spacer element P2 can be ensured to be reasonable, avoiding spatial conflicts or waste; optimizing the positional relationship between the lens barrel and the spacer element can improve the performance of the optical system without incurring excessive costs; a reasonable layout also helps to reduce material consumption and manufacturing costs.

[0095] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 0.15 < CP1 / (CT1 + T12) < 0.80, where CP1 is the maximum thickness of the first spacer element P1 along the optical axis direction, CT1 is the central thickness of the first lens E1 on the optical axis, and T12 is the air gap between the first lens E1 and the second lens E2 on the optical axis.

[0096] In this preferred embodiment of the present application, by restricting the ratio between CP1 and (CT1 + T12) within the range of 0.15 < CP1 / (CT1 + T12) < 0.80, it helps to ensure the compactness of the optical system. This inequality requires that the thickness of the first spacer element P1 cannot be too large so as not to occupy too much space, and at the same time cannot be too small to ensure its structural stability and functionality. This balanced design enables the optical system to achieve optimal performance within a limited space, meeting the requirements of modern optical devices for miniaturization and portability. For example, when designing small optical systems such as head-mounted display devices or micro cameras, compactness is a key consideration. By reasonably controlling the parameters of CP1, CT1, and T12, the optical system can be made smaller, lighter, and more convenient to carry and use.

[0097] It is worth mentioning that although this inequality is directly related to the ratio of physical dimensions, it indirectly affects the imaging quality of the optical system. The thickness of the first spacer element P1, the central thickness of the lens, and the air gap between the lenses are all important factors affecting the light propagation path and aberration. By optimizing the ratio of these parameters, aberrations such as spherical aberration, coma, and astigmatism can be reduced, thereby improving the clarity and resolution of the image.

[0098] Spherical aberration is an aberration caused by the different focusing abilities of the lens for light of different wavelengths. By reasonably adjusting the parameters of CP1, CT1, and T12, the light can be focused more evenly when passing through the lens and the spacer element, reducing the influence of spherical aberration. Coma is an aberration caused by the uneven refraction of light when passing through the edge of the lens. By optimizing the shape of the lens and the position of the spacer element, the generation of coma can be reduced. Astigmatism is an aberration caused by the different focusing abilities of light in different directions. By adjusting the air gap between the lenses and the thickness of the spacer element, the propagation of light in different directions can be made more uniform, reducing the influence of astigmatism.

[0099] It can be understood that these parameters can be adjusted according to specific requirements (such as focal length, field of view angle, aperture size, etc.) to achieve the best optical performance. For example, in a design that requires a longer focal length or a larger field of view angle, it may be necessary to increase the air gap T12 between the lenses, and at the same time appropriately adjust the thickness CP1 of the first spacer element P1 to keep the ratio within a reasonable range.

[0100] If a longer focal length is required, usually the distance between the lenses needs to be increased to achieve a farther focus of the light. In this case, the value of T12 can be appropriately increased, and the thickness of CP1 can be adjusted to ensure the compactness and stability of the optical system. If a larger field of view angle is required, then the shape and position of the lens, as well as the thickness and position of the spacer element, need to be optimized to ensure that the light can enter the optical system at a wider angle and form a clear image on the imaging surface.

[0101] In addition, the aperture size also affects the performance of the optical system. A larger aperture allows more light to enter the optical system, improving the brightness and contrast of the image, but may also increase aberration. By reasonably adjusting the parameters of CP1, CT1, and T12, the best imaging effect can be achieved at different aperture sizes.

[0102] When the optical system of the head-mounted device in the preferred embodiment of the present application satisfies: 0.15 < CP1 / (CT1 + T12) < 0.80, by restricting the ratio of the thickness of the first spacer element P1 to the sum of the central thickness of the first lens E1 and the air gap between the first lens E1 and the second lens E2 on the optical axis, the compactness of the optical system can be ensured, the imaging quality can be improved, and different design requirements can be met. Designers can reasonably adjust these parameters according to specific application scenarios and performance requirements to achieve the best optical performance.

[0103] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 1.4 < CP2 / T23 < 6.2, where CP2 is the maximum thickness of the second spacer element P2 along the optical axis direction, and T23 is the air gap between the second lens E2 and the third lens E3 on the optical axis.

[0104] In wearable electronic devices, compactness is an important design goal. In the preferred embodiment of the present application, by restricting the ratio of CP2 to T23 within the range of 1.4 < CP2 / T23 < 6.2, the thickness of the second spacer element P2 and the air gap between the two lenses (the second lens E2 and the third lens E3) can be effectively controlled, thereby maintaining the compactness of the system. When the ratio is within this range, it is possible to avoid the second spacer element P2 being too thick and occupying too much space, and prevent it from being too thin to provide sufficient support and adjustment space. At the same time, an appropriate air gap also helps to optimize the propagation of light, reduce unnecessary space waste, and enable the optical system to achieve the best performance within a limited space.

[0105] It is worth mentioning that the thickness of the second spacer element P2 and the air gap between the second lens E2 and the third lens E3 directly affect the layout of the optical elements. By restricting the ratio of CP2 to T23 in the present application, while ensuring the compactness of the system, sufficient space can be left for other optical elements to achieve a reasonable layout.

[0106] The second spacer element P2 in the optical system not only serves to separate optical elements, but also needs to provide certain structural support for the optical elements. An appropriate thickness can ensure that the second spacer element P2 has sufficient strength and stability to withstand the weight of the optical elements and external pressure. At the same time, a certain thickness also provides space for adjusting the position and angle of the optical elements, facilitating the calibration and optimization of the optical system.

[0107] Therefore, when the optical system of the head-mounted device in the preferred embodiment of the present application satisfies: 1.4 < CP2 / T23 < 6.2, that is, by reasonably controlling the ratio of the thickness of the second spacer element P2 and the air gap between the second lens E2 and the third lens E3, while maintaining the compactness of the system, the optical elements can be reasonably arranged to provide sufficient structural support and adjustment space for the optical system, thereby improving the performance and stability of the optical system.

[0108] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 2.05 < d0m / DT32 < 3.30, where d0m is the inner diameter of the plane perpendicular to the optical axis of the image side P02 of the lens barrel, and DT32 is the maximum effective radius of the image side S8 of the third lens.

[0109] It is worth mentioning that aberration in the optical system is an important factor affecting imaging quality; spherical aberration causes light rays not to accurately focus on a single point when passing through the lens, resulting in blurred imaging; coma aberration causes light rays to form comet-shaped light spots on the imaging plane; astigmatism causes the focusing ability of light rays in different directions to be different, resulting in imaging distortion; field curvature causes the imaging plane not to be a plane but a curved surface; distortion causes the shape of the imaging to be distorted. In the preferred embodiment of the present application, by adjusting the ratio of the inner diameter of the plane perpendicular to the optical axis of the image side P02 of the lens barrel to the maximum effective radius of the image side S8 of the third lens within the range of 2.05 < d0m / DT32 < 3.30, these aberrations can be controlled to a certain extent.

[0110] As an example, when the ratio is appropriate, the propagation path of light rays in the optical system can be optimized, reducing the generation of spherical aberration and coma aberration. At the same time, astigmatism and field curvature can also be adjusted to make the imaging plane flatter. In addition, a reasonable ratio can also control distortion, making the shape of the imaging more accurate. By controlling these aberrations, the clarity and resolution of the imaging can be improved, providing a better visual experience for users.

[0111] It can be understood that a larger inner diameter d0m allows more light to enter the system, and more light flux can improve the brightness of the imaging, making the image clearer and more visible. However, an overly large inner diameter will also increase the complexity and cost of the system. On the one hand, a larger lens barrel requires more materials and manufacturing processes, increasing the production cost. On the other hand, a lens barrel with a large inner diameter may introduce more stray light, and additional optical elements are needed to eliminate this stray light, increasing the complexity of the system.

[0112] By setting the proportional relationship between d0m and DT32, it is possible to avoid unnecessary waste and complexity while ensuring sufficient light flux. When the ratio is within an appropriate range, good light flux can be obtained without significantly increasing the system cost and complexity, improving the imaging quality.

[0113] Therefore, when the optical system of the head-mounted device in the preferred embodiment of the present application satisfies: 2.05 < d0m / DT32 < 3.30, that is, by reasonably adjusting the ratio of the inner diameter of the lens barrel to the effective radius of the lens, it can play an important role in controlling aberration and balancing light flux, improving the imaging quality of the optical system, and meeting the requirements of different application scenarios.

[0114] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 35.05 < d2m / |SAG22| < 59.35, where d2m is the inner diameter of the plane perpendicular to the optical axis of the image side of the second spacer element P2, and SAG22 is the axial distance between the intersection of the image side S6 of the second lens and the optical axis and the vertex of the effective radius of the image side S6 of the second lens.

[0115] It is worth mentioning that VR systems usually require a large field of view angle to provide a more immersive experience. In the preferred embodiment of the present application, by adjusting the ratio between d2m and SAG22 within the range of 35.05 < d2m / |SAG22| < 59.35, it is possible to affect the propagation path of light and the focal length of the system, thereby optimizing the field of view angle to a certain extent. When the ratio is appropriate, the light can propagate in a more reasonable manner in the optical system, so that the field of view angle can not only meet the user's demand for an immersive experience, but also not cause excessive aberration to affect the imaging quality.

[0116] The field of view angle can be optimized by adjusting the inner diameter d2m of the spacer element P2 and the SAG22 value of the second lens E2. If the field of view angle is too small, the user will feel that the field of view is narrow and the immersion is insufficient when using the VR system; while if the field of view angle is too large, it may cause image distortion and increased aberration, affecting the imaging quality. By reasonably adjusting this ratio, the field of view angle can be increased as much as possible while ensuring the imaging quality, improving the user experience.

[0117] By adjusting the ratio of d2m to SAG22, while ensuring the imaging quality, the size and weight of the optical system can be optimized. For example, the size of the spacer element P2 can be reduced by decreasing the value of d2m, or the shape and curvature of the second lens E2 can be changed by adjusting the value of SAG22, thereby reducing the volume and weight of the entire optical system. Additionally, by reasonably adjusting this ratio, the propagation path of light can be optimized, the generation of aberrations can be reduced, and the imaging quality can be improved.

[0118] When the optical system of the head-mounted device in the preferred embodiment of this application satisfies: 35.05 < d2m / |SAG22| < 59.35, that is, by adjusting the ratio between the inner diameter of the spacer element P2 and the SAG22 value of the image side surface S6 of the second lens, the field of view angle can be optimized, the relationship between the system size and performance can be balanced, and the imaging quality and user experience of the VR system can be improved.

[0119] Furthermore, in a specific example of this application, the optical system of the head-mounted device further satisfies the following condition: 0.20 < (d0m - d0s) / f < 1.30, where d0s is the inner diameter of the object side surface P01 of the lens barrel perpendicular to the optical axis plane, and d0m is the inner diameter of the image side surface P02 of the lens barrel perpendicular to the optical axis plane.

[0120] It is worth mentioning that the difference (d0m - d0s) between the inner diameters of the object side and the image side of the lens barrel P0 directly affects the amount of light that the system can collect. A larger difference means that more light can enter the system, thereby improving the light collection efficiency.

[0121] Therefore, in the preferred embodiment of this application, by setting the ratio relationship of 0.20 < (d0m - d0s) / f < 1.30, while ensuring the light collection efficiency, the problems of excessive light divergence or inaccurate focusing can be avoided.

[0122] By adjusting the ratio relationship between the difference in the inner diameters of the object side and the image side of the lens barrel and the focal length, the propagation path of light and the imaging characteristics of the system can be affected, thereby optimizing the imaging quality to a certain extent. Different ratio relationships will cause changes in the refraction, reflection, and focusing methods of light in the optical system, and thus affect aspects such as imaging clarity, contrast, and color reproducibility.

[0123] It is worth mentioning that in the preferred embodiment of this application, by reasonably adjusting this ratio, the generation of aberrations such as spherical aberration, coma aberration, and astigmatism can be reduced. By optimizing the ratio of the difference in the inner diameter of the lens barrel to the focal length, the propagation path of light can be adjusted, the influence of these aberrations can be reduced, and the imaging clarity and resolution can be improved.

[0124] It can be understood that the proportional relationship between the difference in the inner diameters of the object side and the image side of the lens barrel and the focal length is also related to the overall size of the system. Through reasonable adjustment, the size of the system can be minimized as much as possible while ensuring performance. If the inner diameter difference is too large or the focal length is too long, it may lead to an increase in the volume of the lens barrel, which is not conducive to the miniaturization and portability of the system. By optimizing this proportional relationship, the size of the lens barrel can be reduced while meeting the requirements of light collection efficiency and imaging quality, making the optical system more compact. Therefore, by selecting appropriate lens materials and manufacturing processes, and optimizing the layout of the optical system, the size of the lens barrel can be reduced while ensuring imaging quality and light collection efficiency.

[0125] When the optical system of the head-mounted device in the preferred embodiment of the present application satisfies: 0.20 < (d0m - d0s) / f < 1.30, that is, by reasonably adjusting the proportional relationship between the difference in the inner diameters of the object side and the image side of the lens barrel and the focal length, the balance between light collection efficiency and focusing accuracy can be achieved, the imaging quality can be optimized, the system size can be controlled, and the requirements of different application scenarios can be met.

[0126] Further, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 0.95 < d1m / (DT12 * 2) < 1.20, where d1m is the inner diameter of the plane perpendicular to the optical axis of the image side of the first spacer element P1, and DT12 is the maximum effective radius of the image side S4 of the first lens E1.

[0127] In the preferred embodiment of the present application, by adjusting the proportional relationship between d1m and DT12 within the range of 0.95 < d1m / (DT12 * 2) < 1.20, the occurrence of aberration can be controlled to a certain extent. A reasonable proportional setting can optimize the propagation path of light in the optical system, reduce the generation of aberration, and improve the clarity and accuracy of the image.

[0128] When the proportion is appropriate, the light can be focused more evenly when passing through the first spacer element P1 and the first lens E1, reducing the influence of spherical aberration and coma. At the same time, astigmatism and field curvature can also be adjusted to make the imaging plane flatter. In addition, a reasonable proportion can also control distortion to make the shape of the image more accurate. By controlling aberration, the imaging quality of the optical system can be improved, providing a clearer and more accurate image for the user.

[0129] By optimizing the ratio of d1m and DT12, the sizes of the first spacer element P1 and the first lens E1 can be made more compact, thereby reducing the volume of the entire optical system. The size of the first spacer element P1 can be reduced by reducing the value of d1m, or the shape and size of the first lens E1 can be changed by adjusting the value of DT12.

[0130] It is understandable that a reasonable proportional relationship helps to ensure a reasonable relative positional relationship among the various components in the system, thereby improving the overall performance, stability, and reliability of the system. The positional relationship between the first spacer element P1 and the first lens E1 has an important impact on the propagation of light and the imaging quality. If the positional relationship between them is unreasonable, it may lead to inaccurate scattering, reflection, and focusing of light, affecting the imaging quality. Therefore, by adjusting the ratio of d1m to DT12, the relative positions of the first spacer element P1 and the first lens E1 can be made more reasonable, optimizing the light propagation path and improving the performance and stability of the system.

[0131] Optimizing the ratio of d1m to DT12 also helps to reduce the mass of the whole machine. In an optical system, the mass of each component affects the weight and portability of the entire device. By reducing the size and weight of the first spacer element P1 and the first lens E1, the mass of the entire optical system can be reduced, making the device lighter and more convenient to carry and use.

[0132] When the optical system of the head-mounted device in the preferred embodiment of the present application satisfies: 0.95 < d1m / (DT12 * 2) < 1.20, that is, by adjusting the ratio of the inner diameter of the first spacer element P1 to the effective radius of the image side surface S4 of the first lens, the occurrence of aberration can be controlled, the image quality can be improved; the system size can be optimized to achieve a miniaturized design; the relative positions of the components can be ensured to be reasonable, improving the system performance and stability; the mass of the whole machine can be reduced, improving portability. Designers can reasonably adjust this ratio according to specific application requirements and performance requirements to achieve the best optical performance and design goals.

[0133] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 0.95 < (CP1 + E12 + CP2) / (T12 + CT2 + T23) < 2.80, where CP1 is the maximum thickness of the first spacer element P1 along the optical axis direction, CP2 is the maximum thickness of the second spacer element P2 along the optical axis direction, T12 is the air gap between the first lens E1 and the second lens E2 on the optical axis, T23 is the air gap between the second lens E2 and the third lens E3 on the optical axis, and CT2 is the central thickness of the second lens E2 on the optical axis.

[0134] Specifically, in this preferred embodiment of the present application, by adjusting the proportional relationship of 0.95 < (CP1 + E12 + CP2) / (T12 + CT2 + T23) < 2.80, the overall size of the system can be minimized while ensuring the system performance. Smaller intervals and thicknesses mean that the system can be more compact, reducing space occupancy. For wearable devices such as VR headsets, this can improve the wearing comfort and portability. Users will not feel heavy or oppressed when using it, and it is also more convenient to carry and store.

[0135] In addition, in the present application, by adjusting the relative sizes and intervals between the spacer element P and the lens, the optical path length can be controlled. A reasonable optical path length helps to reduce the loss and distortion of light during propagation, thereby optimizing the imaging quality. If the optical path length is too long, light may scatter, be absorbed, etc. during propagation, resulting in a decrease in imaging brightness and clarity; if the optical path length is too short, the optical performance of the lens may not be fully utilized, which will also affect the imaging quality.

[0136] It can be understood that when designing a VR optical system, it is necessary to balance the relationship between system performance and cost. Smaller intervals and thicknesses may mean lower manufacturing costs because the amount of material used and the complexity of the manufacturing process can be reduced. However, at the same time, it may also have a certain impact on system performance. By setting this proportional relationship, the manufacturing cost can be minimized while ensuring that the system performance meets the requirements.

[0137] When the optical system of the head-mounted device in this preferred embodiment of the present application satisfies: 0.95 < (CP1 + E12 + CP2) / (T12 + CT2 + T23) < 2.80, that is, by adjusting this proportional relationship, the system size can be reduced, the portability and comfort can be improved; the optical path length can be controlled to optimize the imaging quality; the system performance and cost can be balanced to achieve a more efficient and economical design.

[0138] Further, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: -4.85 < f23 / R5 * (CP2 / T23) < 9.3, where f23 is the combined focal length of the second lens E2 and the third lens E3, R5 is the curvature radius of the object side surface S7 of the third lens, and T23 is the air interval between the second lens E2 and the third lens E3 on the optical axis.

[0139] Specifically, in this preferred embodiment of the present application, the proportional relationship between the combined focal length f23 and the curvature radius R5 of the object side surface of the third lens E3 directly affects the imaging performance of the system. Therefore, in this preferred embodiment of the present application, by adjusting this ratio, the focusing characteristics of light can be controlled. The ratio between the thickness CP2 of the second spacer element P2 and the air gap T23 also plays a similar role. They jointly affect the propagation path of light and the imaging effect. By reasonably adjusting these two ratios, the propagation of light in the optical system can be optimized, the generation of aberrations can be reduced, and the imaging quality can be improved.

[0140] It can be understood that smaller gaps and thicknesses mean that the system can be more compact, reducing the size and weight of the system. This is very important for VR devices because lightweight devices can improve wearing comfort and portability. By reasonably adjusting the ratio of CP2 and T23, the thickness of the spacer element P2 and the air gap can be reduced, thus making the optical system more compact.

[0141] Different VR optical systems may have different design requirements and goals. Some systems may focus more on imaging quality, while others may focus more on the lightweight and cost-effectiveness of the system. Therefore, by adjusting the proportional relationship of -4.85 < f23 / R5 * (CP2 / T23) < 9.3, VR optical systems that meet different requirements can be designed.

[0142] When the optical system of the head-mounted device in this preferred embodiment of the present application satisfies: -4.85 < f23 / R5 * (CP2 / T23) < 9.3, that is, by adjusting this proportional relationship, the focusing characteristics of light can be controlled, the imaging quality can be optimized; the size and weight of the system can be reduced, and the wearing comfort and portability can be improved; different design requirements can be adapted to design a more excellent VR optical system.

[0143] Furthermore, in a specific example of the present application, the optical system of the head-mounted device further satisfies the following condition: 0.05 < CP2 / |SAG31| < 0.30, where SAG31 is the axial distance between the intersection point of the object side surface S7 of the third lens and the optical axis and the vertex of the effective radius of the object side surface S7 of the third lens.

[0144] Specifically, in this preferred embodiment of the present application, by restricting the ratio range of CP2 to |SAG31| within 0.05 < CP2 / |SAG31| < 0.30, the tilt and eccentricity of the lens can be indirectly controlled. If the lens has a large tilt or eccentricity, the light will deviate from the ideal path when passing through the lens, resulting in problems such as blurred imaging, distortion, or chromatic aberration, which will seriously affect the imaging effect. In addition, the tilt and eccentricity of the lens may also cause a decrease in the stability of the optical system, and it is easily affected by external vibrations and other factors during use, further reducing the imaging quality. By reasonably controlling this ratio range, the position of the third lens E3 on the optical axis can be ensured to be accurate, reducing the occurrence of tilt and eccentricity, thereby guaranteeing the imaging quality and stability of the system.

[0145] It is worth mentioning that although this inequality itself does not directly relate to the overall size of the system, by reasonably controlling the ratio relationship between CP2 and SAG31, the size of some components in the system can be minimized while ensuring the system performance. For wearable devices such as VR headsets, the compactness of the system is crucial. A smaller volume and weight can improve the wearing comfort and reduce the burden on the user's head. At the same time, it is also convenient for carrying and using, increasing the portability of the device. For example, when designing a VR optical system, by reasonably controlling the ratio relationship between CP2 and SAG31, the optical system can be made more compact and lightweight, improving the user experience.

[0146] During the manufacturing process of the optical system, it is necessary to precisely control the size and shape of each component to ensure that the system performance meets the design requirements. The ratio range of CP2 and SAG31 provides a specific target for size control during the manufacturing process, helping to improve the manufacturing accuracy. At the same time, during the assembly process of the system, the position of the lens and the thickness of the spacer element can also be adjusted according to this ratio range to ensure the relative position of each component is accurate.

[0147] Improving the manufacturing and assembly accuracy can reduce the performance degradation caused by manufacturing and assembly errors. If there are large errors during the manufacturing and assembly processes, the imaging quality of the optical system may decrease, or even the system may not work properly. By strictly controlling the ratio relationship between CP2 and SAG31, the influence of these errors can be effectively reduced, improving the performance stability of the system.

[0148] When the optical system of the head-mounted device in the preferred embodiment of the present application satisfies: 0.05 < CP2 / |SAG31| < 0.30, that is, by reasonably controlling the proportional relationship between the thickness CP2 of the spacer element P2 and the axial distance SAG31 on the object side of the third lens, the tilt and eccentricity of the lens can be indirectly controlled, ensuring imaging quality and stability; realizing the compact design of the system, improving the comfort and portability of wearing; providing clear guidance for the manufacturing and assembly processes, improving the manufacturing and assembly accuracy, and reducing performance degradation.

[0149] As Figures 1 to 9 Shown in the figure are 9 different specific embodiments of the optical system of the head-mounted device in the preferred embodiment of the present application. Among them, the optical elements in the optical systems of Embodiment 1, Embodiment 2, and Embodiment 3 have the same optical characteristics; among them, the optical elements in the optical systems of Embodiment 4, Embodiment 5, and Embodiment 6 have the same optical characteristics; among them, the optical elements in the optical systems of Embodiment 7, Embodiment 8, and Embodiment 9 have the same optical characteristics, such as the surface type, radius of curvature, thickness, material, etc. of each surface. The difference lies in the above relationships.

[0150] FIG. 10A to FIG. 10C Shows the axial chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of the head-mounted device in the first to third preferred embodiments of the present invention; FIG. 11A to FIG. 11C Shows the axial chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of the head-mounted device in the fourth to sixth preferred embodiments of the present invention; FIG. 12A to FIG. 12C Shows the axial chromatic aberration curve, astigmatism curve, and distortion curve of the optical system of the head-mounted device in the seventh to ninth preferred embodiments of the present invention; Fig.13 Shows the size of the optical system of the head-mounted device in the first preferred embodiment of the present invention; Fig.14 Shows the size of the first lens of the optical system of the head-mounted device in the first preferred embodiment of the present invention.

[0151] Specifically, Table 1 shows the optical parameters of each optical element in Embodiment 1, Embodiment 2, and Embodiment 3 of the present invention; Table 2 shows the surface parameters of the lenses of each optical element in Embodiment 1, Embodiment 2, and Embodiment 3 of the present invention.

[0152] Table 1 Optical parameters of each optical element in Embodiment 1, Embodiment 2, and Embodiment 3

[0153]

[0154]

[0155] Table 2 Surface parameters of the lenses of each optical element in Embodiment 1, Embodiment 2, and Embodiment 3

[0156] surface 3 4 5 6 7 A4 -2.3109E-07 9.3349E-07 1.0325E-05 2.1320E-06 1.0605E-05 A6 5.5331E-10 -4.2345E-10 1.7868E-08 1.5578E-08 -1.1391E-07 A8 1.7081E-12 9.4844E-12 2.6550E-11 3.2325E-11 1.8865E-10 A10 -3.3433E-15 -1.6437E-14 3.1407E-14 7.2565E-15 -1.5117E-13 A12 0.0000E+00 1.1039E-17 -7.4441E-17 -1.7271E-16 6.9996E-17 A14 0.0000E+00 -2.7319E-21 0.0000E+00 0.0000E+00 -1.9705E-20 A16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 3.3338E-24 A18 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 -3.1204E-28 A20 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 1.2428E-32

[0157] Table 3 shows the optical parameters of each optical element in the fourth embodiment, the fifth embodiment and the sixth embodiment of the present invention; Table 4 shows the surface parameters of the lens of each optical element in the fourth embodiment, the fifth embodiment and the sixth embodiment of the present invention.

[0158] Table 3 Optical parameters of each optical element in Example 4, Example 5 and Example 6

[0159]

[0160] Table 4 Surface parameters of lenses of various optical elements in Embodiment 4, Embodiment 5 and Embodiment 6

[0161]

[0162]

[0163] Table 5 shows the optical parameters of each optical element in Embodiment 7, Embodiment 8 and Embodiment 9 of the present invention; Table 6 shows the surface parameters of the lens of each optical element in Embodiment 7, Embodiment 8 and Embodiment 9 of the present invention.

[0164] Table 5 Optical parameters of each optical element in Example 7, Example 8 and Example 9

[0165]

[0166] Table 6 Surface parameters of lenses of various optical elements in Embodiment 7, Embodiment 8 and Embodiment 9

[0167] surface 3 4 5 6 7 8 A4 -4.2137E-08 0.0000E+00 -1.8579E-05 0.0000E+00 0.0000E+00 -2.9287E-05 A6 -1.4631E-09 0.0000E+00 7.0560E-09 0.0000E+00 0.0000E+00 1.4825E-07 A8 2.9789E-13 0.0000E+00 1.5033E-10 0.0000E+00 0.0000E+00 -2.2567E-10 A10 -3.3682E-14 0.0000E+00 1.2382E-13 0.0000E+00 0.0000E+00 1.7249E-13 A12 -3.9252E-17 0.0000E+00 -1.8394E-16 0.0000E+00 0.0000E+00 -7.3184E-17 A14 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 1.7134E-20 A16 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 -1.9295E-24 A18 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 4.1953E-29 A20 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 6.3544E-33

[0168] Table 7 shows the characteristic data of each parameter in Example 1 (1) to Example 9 (9) of the present application.

[0169] Table 7 Parameter characteristic data in Examples 1 to 9

[0170]

[0171]

[0172] Table 8 shows the characteristic data of each parameter in Example 1 (1) to Example 9 (9) of the present application.

[0173] Table 8 Parameter characteristic data in Examples 1 to 9

[0174] Example Data 1 2 3 4 5 6 7 8 9 d1s 42.93 42.92 41.82 40.06 41.00 41.98 38.05 38.66 43.08 d1m 44.18 44.19 40.89 42.23 39.64 39.51 39.18 39.92 35.66 D1s 45.71 45.74 45.09 42.71 43.28 44.63 43.90 42.96 45.27 d2m 43.00 45.71 36.71 42.31 42.15 39.95 37.50 37.49 39.03 d0s 30.95 30.54 31.00 31.54 31.54 31.54 31.75 31.75 31.01 d0m 52.52 49.92 34.69 49.44 49.34 37.50 49.01 49.01 35.66 EP01 6.58 6.59 6.59 8.09 8.09 8.09 6.63 6.63 6.02 CP1 6.51 5.82 5.82 4.76 4.76 4.76 1.28 2.08 2.08 EP12 1.34 2.03 2.33 1.72 1.72 1.98 5.86 5.07 5.43 CP2 3.85 4.59 4.56 1.21 1.21 0.85 2.44 2.44 2.08 EP02 14.43 14.44 14.74 14.58 14.58 14.84 13.78 13.78 13.53 L 24.00 21.62 22.37 20.38 20.43 21.08 21.01 21.01 19.04

[0175] Table 9 shows the conditional data in Examples 1 (1) to 9 (9) of the present application.

[0176] Table 9 Conditional formula data in Examples 1 to 9

[0177] Conditional / Example 1 2 3 4 5 6 7 8 9 d1m / F1 2.29 2.29 2.12 1.53 1.43 1.43 2.16 2.20 1.97 L / f 1.39 1.25 1.29 0.92 0.93 0.96 1.22 1.22 1.11 EP12 / (d1s-2*DT11) 0.34 0.51 0.81 0.39 0.32 0.31 2.54 1.74 0.74 (D1s-d1m) / |SAG11| 10.71 10.86 12.60 2.41 2.07 2.41 5.60 4.12 2.10 EP01 / CT1 0.82 0.82 0.82 1.21 1.21 1.21 1.11 1.11 1.00 L / EP02 1.66 1.50 1.52 1.40 1.40 1.42 1.52 1.52 1.41 CP1 / (CT1+T12) 0.77 0.68 0.68 0.64 0.64 0.64 0.18 0.30 0.30 CP2 / T23 5.17 6.16 6.12 2.07 2.07 1.45 3.16 3.16 2.69 d0m / DT32 3.26 3.10 2.15 2.74 2.74 2.08 2.89 2.89 2.11 d2m / |SAG22| 54.38 57.80 46.42 59.30 59.08 56.00 35.10 35.09 36.53 (d0m-d0s) / f 1.25 1.12 0.21 0.81 0.81 0.27 1.00 1.00 0.27 d1m / (DT12*2) 1.13 1.13 1.05 1.16 1.09 1.08 1.08 1.10 0.98 (CP1+E12+CP2) / (T12+CT2+T23) 2.54 2.70 2.76 0.98 0.98 0.97 1.16 1.16 1.16 f23 / R5*(CP2 / T23) 7.76 9.25 9.19 -1.05 -1.05 -0.74 -4.81 -4.81 -4.10 CP2 / |SAG31| 0.23 0.28 0.28 0.07 0.07 0.05 0.14 0.14 0.12

[0178] According to another aspect of the present application, the present application further provides a head-mounted device, wherein the head-mounted device may be but is not limited to an AR device or a VR device, such as AR (VR) glasses, wherein the head-mounted device includes a head-mounted device body (not shown in the figure) and at least one optical system arranged on the head-mounted device body, and the at least one optical system is mounted on the head-mounted device body. The at least one optical system is as described in any of the above embodiments, and the present application will not elaborate on this.

[0179] It should be understood by those skilled in the art that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. An optical system of a head mounted device, characterized in that: Comprising: A lens barrel; A lens group, wherein the lens group includes a reflective polarizing element, a quarter-wave plate, a first lens, a second lens, and a third lens. The reflective polarizing element, the quarter-wave plate, and the first lens form an optical element group, and the optical element group has a positive optical power. The second lens has a positive optical power, the third lens has an optical power, and the image sides of the second lens and the third lens are convex; and a spacer element, wherein the spacer element includes a first spacer element, and the first spacer element is located between the first lens and the second lens and abuts against the second side surface of the first lens. The optical system satisfies the following conditions: 0.9 < L / f < 1.4 and 1.4 < d1m / F1 < 2.3, where f is the effective focal length of the optical system, L is the maximum horizontal distance along the optical axis from the object side surface to the image side surface of the lens barrel, F1 is the focal length of the optical element group, and d1m is the inner diameter of the plane perpendicular to the optical axis of the image side surface of the spacer element.

2. The optical system of the head-mounted device according to claim 1, wherein the spacer element further includes a second spacer element, and the second spacer element is disposed between the second lens and the third lens. The optical system of the head-mounted device further satisfies the following condition: 0.30 < EP12 / (d1s - 2*DT11) < 2.55, where EP12 is the axial spacing distance between the image side surface of the first spacer element and the object side surface of the second spacer element, d1s is the inner diameter of the plane perpendicular to the optical axis of the object side surface of the spacer element, and DT11 is the maximum effective radius of the object side surface of the first lens.

3. The optical system of the head-mounted device according to claim 2, wherein the optical system of the head-mounted device further satisfies the following condition: 2.0<(D1s-d1m) / |SAG11|≤12.6, wherein, d1m is the inner diameter of the plane perpendicular to the optical axis of the image side surface of the first spacer element, D1s is the outer diameter of the plane perpendicular to the optical axis of the object side surface of the first spacer element, and SAG11 is the axial distance between the intersection of the object side surface of the first lens and the optical axis and the vertex of the effective radius of the object side surface of the first lens.

4. The optical system of the head-mounted device according to claim 3, wherein the optical system of the head-mounted device further satisfies the following condition: 0.80 < EP01 / CT1 < 1.25, where, EP01 is the axial spacing distance from the object side end face of the lens barrel to the object side surface of the first spacer element, and CT1 is the central thickness of the first lens on the optical axis.

5. The optical system of the head-mounted device according to claim 4, wherein the optical system of the head-mounted device further satisfies the following condition: 1.4≤L / EP02<1.7, wherein, L is the maximum horizontal distance along the optical axis from the object side end face to the image side end face of the lens barrel, and EP02 is the axial spacing distance from the object side end face of the lens barrel to the object side surface of the second spacer element.

6. The optical system of the head-mounted device according to claim 5, wherein the optical system of the head-mounted device further satisfies the following condition: 0.15 < CP1 / (CT1 + T12) < 0.80, where, CP1 is the maximum thickness of the first spacer element along the optical axis, CT1 is the central thickness of the first lens on the optical axis, and T12 is the air gap between the first lens and the second lens on the optical axis.

7. The optical system of the head-mounted device according to claim 6, wherein the optical system of the head-mounted device further satisfies the following condition: 1.4 < CP2 / T23 < 6.2, where, CP2 is the maximum thickness of the second spacer element along the optical axis, and T23 is the air gap between the second lens and the third lens on the optical axis.

8. The optical system of the head-mounted device according to claim 7, wherein the optical system of the head-mounted device further satisfies the following condition: 2.05 < d0m / DT32 < 3.30, where, d0m is the inner diameter of the plane perpendicular to the optical axis of the image side surface of the lens barrel, and DT32 is the maximum effective radius of the image side surface of the third lens.

9. The optical system of the head-mounted device according to claim 8, wherein the optical system of the head-mounted device further satisfies the following condition: 35.05 < d2m / |SAG22| < 59.35, where, d2m is the inner diameter of the plane perpendicular to the optical axis of the image side surface of the second spacer element, and SAG22 is the axial distance between the intersection of the image side surface of the second lens and the optical axis and the vertex of the effective radius of the image side surface of the second lens.

10. The optical system of the head-mounted device according to claim 9, wherein the optical system of the head-mounted device further satisfies the following condition: 0.20<(d0m-d0s) / f<1.30, wherein, d0s is the inner diameter of the plane on the object side of the lens barrel that is perpendicular to the optical axis, and d0m is the inner diameter of the plane on the image side of the lens barrel that is perpendicular to the optical axis.

11. The optical system of the head-mounted device according to claim 10, wherein the optical system of the head-mounted device further satisfies the following condition: 0.95 < d1m / (DT12*2) < 1.20, where, d1m is the inner diameter of the plane of the image side surface of the first spacer element perpendicular to the optical axis, and DT12 is the maximum effective radius of the image side surface of the first lens.

12. The optical system of the head-mounted device according to claim 11, wherein the optical system of the head-mounted device further satisfies the following condition: 0.95<(CP1+E12+CP2) / (T12+CT2+T23)<2.80, wherein, CP1 is the maximum thickness of the first spacing element along the optical axis, CP2 is the maximum thickness of the second spacing element along the optical axis, T12 is the air spacing between the first lens and the second lens on the optical axis, T23 is the air spacing between the second lens and the third lens on the optical axis, and CT2 is the center thickness of the second lens on the optical axis.

13. The optical system of the head-mounted device according to claim 12, wherein the optical system of the head-mounted device further satisfies the following condition: -4.85 < f23 / R5*(CP2 / T23) < 9.3, where, f23 is the combined focal length of the second lens and the third lens, R5 is the radius of curvature of the object side of the third lens, and T23 is the air distance between the second lens and the third lens on the optical axis.

14. The optical system of the head-mounted device according to claim 13, wherein the optical system of the head-mounted device further satisfies the following condition: 0.05 < CP2 / |SAG31| < 0.30, where, SAG31 is the on-axis distance between the intersection of the objective side of the third lens and the optical axis to the vertex of the effective radius of the objective side of the third lens.

15. A head-mounted device, characterized in that: include: A head mounted device body; and At least one optical system as claimed in any one of claims 1 to 14, wherein the optical system is mounted on the head-mounted device body.

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