Pupil-exit miniaturized large field of view high resolution low distortion human eye-like lens

Abstract

The application provides a small-size large-view-field high-resolution low-distortion human-eye-simulating lens with a pupil outside, which comprises, in sequence from an object side to an image side, an aperture for simulating a human eye pupil, a lens set comprising first to seventh lenses arranged in sequence from the object side to the image side and having air gaps between each adjacent lens; wherein the first lens is an aspherical lens, and the second to seventh lenses are spherical lenses; wherein the first, fourth and fifth lenses have positive focal powers, and the second, third, sixth and seventh lenses have negative focal powers; wherein a separation distance ST of the aperture and the first lens on an optical axis is greater than or equal to 8 mm; a focal length f1 of the first lens and a central thickness d1 satisfy: 8.17 <= |f1 / d1| <= 18.88; and a combined focal length f02 of the second to seventh lenses and an effective focal length f of the human-eye-simulating lens satisfy: 2.08 <= |f02 / f| <= 6.75.

Description

Technical Field

[0001] This invention belongs to the field of performance testing of visual display devices, and relates to a miniaturized, large field of view, high-resolution, low-distortion humanoid eyeglass lens with an external pupil. Background Technology

[0002] With the rapid popularization of next-generation visual display technologies such as VR / AR, near-eye displays, automotive HUDs, and smart glasses, the market's demands for the visual experience of head-mounted display devices are increasing. As the core hardware of these display devices, the optical performance of the humanoid eyepiece directly determines the calibration accuracy and reliability of the testing equipment, and its design requirements are becoming increasingly stringent. An ideal humanoid eyepiece needs to accurately simulate the optical characteristics of the human eye, including a specific entrance pupil diameter, a reasonable field of view, high resolution, and low distortion.

[0003] Existing anthropomorphic eyeglass lenses generally have many lenses and are large in size, which is not conducive to the performance testing of display devices, and the field of view is also limited, failing to meet the growing technical demand for miniaturization and large field of view. In pursuit of high image quality, most existing technologies adopt a multi-spherical lens design, which is too complex and not conducive to miniaturization design.

[0004] Patent CN111367044A discloses a humanoid eyeglass lens. Although the number of lenses is small, according to the provided embodiment, the total length from the first lens to the image plane is 51.08mm, which is still relatively long. Furthermore, the field of view is only 50°, ensuring high-quality imaging within a 40° field of view. Although the system aperture is external, the distance from it to the first lens is only 4.84mm. Because the outermost surface of the first lens is concave, the actual distance from the pupil to the lens end face is far less than 4.84mm, which is not conducive to matching and interfacing with display devices. This solution uses two sets of double-laminated lenses. During the lamination process, bubbles, impurities, uneven adhesive layer thickness, and edge overflow are easily generated, causing stray light, scattering noise, and reduced transmittance, affecting the system's imaging quality. Moreover, the environmental stability is poor; high and low temperature cycling and humid environments can easily lead to adhesive layer aging, yellowing, delamination, or peeling, posing a risk of insufficient long-term stability. In addition, the sixth biconvex lens in this solution presents significant manufacturing difficulties, greatly impacting the practical application value of the solution.

[0005] Patent CN120276125A discloses a humanoid eyeglass lens with 14 lenses, which is relatively numerous. The system is quite long, with a maximum field of view of only 43° and a maximum distortion of nearly 2%, indicating significant system distortion. Furthermore, the system contains three sets of cemented doublet lenses, resulting in the aforementioned drawbacks of poor image quality and poor environmental stability.

[0006] Patent CN120065455A discloses a humanoid eyeglass lens with 17 lenses, a relatively large number, resulting in a long system size. Although the system aperture is external, the distance between it and the first lens is only 0.1mm, which is not conducive to matching and docking with display devices during use. Furthermore, the system's field of view is only 30°, and the edge field of view distortion is very large, exceeding 50%, seriously affecting image quality. Additionally, the system contains a triple-laminated lens. As mentioned above, laminated lenses pose risks of poor environmental stability and defects in the lamination layer, which can affect image quality.

[0007] In addition, most existing humanoid glasses lenses have the pupil aperture built in to achieve the technical goal of low distortion and high resolution. However, this design is not conducive to the matching and docking of the device with the display system during use, and does not meet the practical scenarios and pupil matching requirements of humanoid glasses lenses.

[0008] Patent CN120630451A discloses a compact, wide-field-of-view anthropomorphic lens. This lens has 13 lenses, which is relatively numerous, resulting in a long system size. The aperture stop is located between the first and second lenses, and it is not an external pupil system. The system contains three sets of cemented triplet lenses, exhibiting the drawbacks of poor image quality and poor environmental stability found in the aforementioned systems.

[0009] In summary, existing external pupil anthropomorphic lenses struggle to achieve an ideal balance across multiple performance dimensions, including a wide field of view, high resolution, low distortion, miniaturization, accurate pupil simulation, and high stability. In particular, under the condition of ensuring that the entrance pupil diameter simulates the human eye and that an aperture stop is placed in front, how to simultaneously achieve effective compression of the total optical length, improvement of edge field of view imaging quality, and enhancement of temperature stability through reasonable optical power allocation and lens configuration design has become a technical challenge that urgently needs to be solved by those skilled in the art.

[0010] In view of this, designing a miniaturized, wide-field-of-view, high-resolution, low-distortion humanoid eyepiece with an external pupil has significant application value and technical significance. Summary of the Invention

[0011] The purpose of this invention is to solve the technical problems of existing pupil-external anthropomorphic eyepieces, which are difficult to achieve an ideal balance in multiple performance dimensions such as large field of view, high resolution, low distortion, miniaturization, accurate pupil simulation and high stability, and have the disadvantages of large number of lenses, difficulty in miniaturization, poor system imaging quality and poor environmental stability. Specifically, this invention provides a miniaturized pupil-external anthropomorphic eyepiece with a large field of view, high resolution and low distortion.

[0012] To achieve the above objectives, the present invention proposes the following technical solution: Firstly, a miniaturized, wide-field-of-view, high-resolution, low-distortion humanoid eyepiece with an external pupil is proposed. The humanoid eyepiece, from its object side to its image side, comprises: An aperture is used to simulate the pupil of the human eye; The lens group includes a first lens to a seventh lens arranged sequentially from the object side to the image side, and there is an air gap between each adjacent lens; The first lens is an aspherical lens, while the second to seventh lenses are all spherical lenses. The first lens, the fourth lens, and the fifth lens have positive optical power, while the second lens, the third lens, the sixth lens, and the seventh lens have negative optical power. Wherein, the distance ST between the aperture and the first lens on the optical axis is ≥8 mm; The focal length f1 and center thickness d1 of the first lens satisfy: 8.17 ≤ |f1 / d1| ≤ 18.88; The combined focal length f02 of the second lens to the seventh lens and the effective focal length f of the anthropomorphic lens satisfy: 2.08 ≤ |f02 / f| ≤ 6.75.

[0013] Furthermore, the maximum field of view (FOV) of the anthropomorphic eyepiece is 55°.

[0014] Furthermore, the anthropomorphic lens satisfies the following conditions: TTL / N ≤ 6.2, and TTL < 43 mm; Wherein, TTL is the distance on the optical axis from the center of the object side of the first lens to the imaging surface of the anthropomorphic eyepiece, and N is the number of lenses in the lens group.

[0015] Furthermore, the anthropomorphic lens satisfies: TTL / IH ≤ 2.8; Wherein, TTL is the distance on the optical axis from the center of the object side of the first lens to the imaging surface of the humanoid eyepiece, and IH is the maximum effective image circle radius on the imaging surface of the humanoid eyepiece.

[0016] Furthermore, the anthropomorphic lens satisfies: 1.43 < |TTL / f| < 1.46; Wherein, TTL is the distance on the optical axis from the center of the object side of the first lens to the imaging surface of the humanoid eyepiece, and f is the effective focal length of the humanoid eyepiece.

[0017] Furthermore, the anthropomorphic lens satisfies: 3.41 ≤ |f / EPD| ≤ 3.70, and EPD ≥ 8 mm; Wherein, EPD is the entrance pupil diameter of the anthropomorphic lens, and f is the effective focal length of the anthropomorphic lens.

[0018] Furthermore, at a spatial frequency of 120 lp / mm, the MTF modulation transfer function value of the anthropomorphic eyepiece is ≥0.2 across the entire field of view.

[0019] Furthermore, the anthropomorphic lens satisfies: |Dist| < 0.3%; Where Dist is the optical distortion value of the anthropomorphic lens at its maximum field of view.

[0020] Furthermore, the first lens includes a first surface located on the object side and a second surface located on the image side; The first surface is an even-order aspherical surface, and the second surface is a spherical surface.

[0021] Furthermore, the refractive index Nd1 and its Abbe number Vd1 of the first lens satisfy: 1.55≤ Nd1≤1.61, 60≤ Vd1≤68; The refractive index Nd2 and its Abbe number Vd2 of the second lens satisfy: 1.56≤ Nd2≤1.65, 36≤ Vd2≤58; The refractive index Nd3 and its Abbe number Vd3 of the third lens satisfy: 1.75≤ Nd3≤1.81, 22≤ Vd3≤27; The refractive index Nd4 and its Abbe number Vd4 of the fourth lens satisfy: 1.58 ≤ Nd4 ≤ 1.61, 67 ≤ Vd4 ≤ 69; The refractive index Nd5 and its Abbe number Vd5 of the fifth lens satisfy: 1.64≤ Nd5≤1.76, 50≤ Vd5≤56; The refractive index Nd6 and its Abbe number Vd6 of the sixth lens satisfy: 1.71≤ Nd6≤1.81, 23≤ Vd6≤28; The refractive index Nd7 and its Abbe number Vd7 of the seventh lens satisfy: 1.51≤ Nd7≤1.57, 60≤ Vd7≤65.

[0022] The beneficial effects of this invention are: The present invention provides a miniaturized, large field of view, high-resolution, low-distortion humanoid eyeglass lens with an external pupil, which simulates the optical characteristics of the human eye. The lens has an external pupil and features miniaturization, large field of view, high resolution, and low distortion. When placed in front of a visual display device, it can accurately measure the optical performance of the visual display device.

[0023] On the one hand, this invention achieves a large field of view imaging with an external pupil, reaching up to 55°, and the pupil is no less than 8mm, which covers the maximum pupil size of healthy individuals without drug intervention, conforming to the actual characteristics of the human eye and improving the reliability of performance testing of visual display devices. On the other hand, this invention achieves system miniaturization, with the total length from the first lens to the image plane being less than 43mm, significantly smaller than the size of humanoid glasses lenses in the prior art, realizing a small-sized humanoid glasses lens design, which is beneficial for the system construction during visual display device testing and can be used in AR / VR glasses with temples and related application scenarios.

[0024] On the other hand, this invention achieves high resolution and low distortion imaging under the premise of full field of view. The full field of view resolution can reach 0.2 at 120 lp / mm, and the maximum distortion does not exceed 0.3%, resulting in high imaging quality and significantly improving the accuracy of performance testing of visual display devices. This invention has a simple structure, with the entire system containing only seven lenses, including one aspherical lens, thereby achieving better aberration correction effect and avoiding the use of cemented lenses. This solves the technical problems of high assembly and adjustment difficulty, poor system imaging quality, and poor environmental stability caused by the use of cemented lenses.

[0025] In summary, this invention employs a front-aperture optical system composed of seven independent single lenses, without using any double or triple bonded structures. It adopts a chromatic aberration correction mechanism that is fundamentally different from traditional bonded structures. Through the alternating arrangement of high and low Abbe number glass and the matching of refractive index gradients, it achieves systematic correction of axial chromatic aberration, magnification chromatic aberration, and monochromatic aberration, resulting in a miniaturized, large field of view, high resolution, and low distortion lens effect.

[0026] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below can be considered part of the inventive subject matter of this disclosure, provided that such concepts do not contradict each other. Attached Figure Description

[0027] The accompanying drawings are not drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures can be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the invention will now be described by way of example and with reference to the accompanying drawings. The embodiments in the drawings do not constitute any limitation on the invention. Other drawings can be obtained by those skilled in the art based on the following drawings without inventive effort, wherein: Figure 1 This is a schematic diagram of the structure of the anthropomorphic eyeglass lens provided by the present invention; Figure 2 This is the MTF curve of the anthropomorphic eyeglass lens provided in Embodiment 1 of the present invention; Figure 3 This is the distortion curve of the anthropomorphic eyeglass lens provided in Embodiment 1 of the present invention; Figure 4 This is the MTF curve of the anthropomorphic eyeglass lens provided in Embodiment 2 of the present invention; Figure 5 This is the distortion curve of the anthropomorphic eyeglass lens provided in Embodiment 2 of the present invention; Figure 6 This is the MTF curve of the anthropomorphic eyeglass lens provided in Embodiment 3 of the present invention; Figure 7 This is the distortion curve of the anthropomorphic eyeglass lens provided in Embodiment 3 of the present invention.

[0028] Legend: 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Seventh lens. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art.

[0030] The terms "first," "second," and similar terms used in the specification and claims of this patent application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" indicate that the elements or objects preceding "comprising" encompass the features, integrals, steps, operations, elements, and / or components listed following "comprising" or "including," and do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof.

[0031] As a core component for testing AR / VR modules, the anthropomorphic lens is designed to accurately simulate the optical characteristics of the human eye, including entrance pupil position, entrance pupil diameter, field of view, resolution, and distortion control. Specifically, the anthropomorphic lens is not intended to replicate the human eyeball, but rather to simulate the way the human eye observes and to objectively detect and evaluate the characteristic parameters of VR / AR display devices.

[0032] As the core optical system for performance testing of VR / AR display devices, the humanoid eyepiece lens must meet requirements such as high detection accuracy and objective detection characteristic parameters. Therefore, matching the entrance pupil of the humanoid eyepiece lens with the exit pupil of the device under test is a prerequisite for testing. The entrance pupil is defined as follows: In an optical system, the image formed in object space by the aperture stop in front of the optical group is called the entrance pupil of the system.

[0033] Since the human pupil is located at the very front of the eyeball, anthropomorphic eyepieces must place the aperture stop at the very front of the system to simulate the entrance pupil position of the human eye. However, in optical design, placing the aperture stop at the front causes light rays from the edge of a large field of view to enter the first lens at a large angle, resulting in defects such as a sharp decrease in edge illumination, difficulty in correcting off-axis aberrations, and an excessively large aperture of the front lens group, making it difficult to meet the technical requirements of a large field of view.

[0034] To achieve the technical goal of a large field of view, existing technologies typically place the aperture stop in the center, that is, after the first lens element. This results in the entrance pupil of the lens being the image of the aperture stop formed by the first lens element in the object space, which greatly reduces the detection accuracy and objectivity of the lens.

[0035] Therefore, it is generally difficult to simultaneously achieve a front-positioned aperture and a wide field of view in existing technologies. Meanwhile, traditional wide-angle lens designs typically employ a "reverse telephoto structure," i.e., a front negative and rear positive design, using a front negative lens group to expand the field of view. However, to achieve a larger field of view, the negative optical power of the front negative lens group needs to be enhanced, and a sufficiently long back working distance is required to accommodate the subsequent positive lens group. This leads to a significant increase in the overall optical length, resulting in a significant contradiction between the miniaturization requirements of humanoid eyeglass lenses and the need for a large field of view.

[0036] High resolution demands lenses with excellent aberration correction capabilities, especially strict control over spherical and chromatic aberration. Low distortion requires lenses to have stable magnification in the off-axis field of view, which typically requires complex lens assembly, such as symmetrical structures and multi-stage cemented lenses. However, under the dual constraints of an external pupil and a large field of view, the asymmetry of the optical path is significantly enhanced, and spherical aberration and distortion often couple. Correcting spherical aberration may exacerbate distortion, and vice versa. To simultaneously achieve high resolution and low distortion, existing technologies often increase the number of lenses to distribute aberrations. However, an excessive number of lenses significantly increases the difficulty of assembly and adjustment and also hinders miniaturization, limiting the widespread application of such lenses in the VR / AR field.

[0037] This invention overcomes the aforementioned technical biases and achieves an ideal balance in five dimensions: external pupil, large field of view, high resolution, low distortion, and miniaturization. While ensuring the biomimetic requirement of external pupil, it simultaneously achieves a large field of view, high resolution, and low distortion through a simplified optical structure, and effectively compresses the overall optical length.

[0038] See attached document Figure 1 As shown, this invention discloses a miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyeglass lens with an external pupil. The humanoid eyeglass lens comprises, from the object side to the image side, the following components: The aperture, used to simulate the human pupil, is located at the position shown as STO in the figure. It determines the amount of light entering the lens and the depth of field. Opposite to it is the imaging plane located on the other side of the lens group, which is located at the position shown as IMG in the figure. It simulates the human retina and is the position of the image sensor in the detection device.

[0039] The lens group, disposed between the aperture stop and the imaging plane, includes a first lens 1 to a seventh lens 7 arranged sequentially from the object side to the image side, and there is an air gap between each adjacent lens, namely the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6 and the seventh lens 7.

[0040] Among them, the first lens 1 is an aspherical lens, and the second lens 2 to the seventh lens 7 are all spherical lenses with optical power; Among them, the first lens 1, the fourth lens 4 and the fifth lens 5 have positive optical power, and the second lens 2, the third lens 3, the sixth lens 6 and the seventh lens 7 have negative optical power.

[0041] The distance ST between the aperture and the first lens 1 on the optical axis is ≥8 mm.

[0042] Specifically, the aperture stop of the anthropomorphic eyepiece lens provided by this invention is an external aperture stop. There are no optical components in front of the aperture stop, so the aperture stop is the entrance pupil of the lens, which makes it easy to match the entrance pupil of this system with the exit pupil of the device under test during testing. The position of the aperture stop determines the entrance pupil position, principal ray angle, aberration distribution, distortion correction method, and illuminance distribution, and is the core architectural feature of the optical system.

[0043] The above-mentioned lens group achieves aberration correction by combining different lenses, adjusting air gaps and curvature, avoiding the use of cemented lenses, effectively avoiding the risks associated with cemented lenses. The system has no cementing stress and high stability; there are no risks of delamination, mold growth, etc., and the service life is long; the overall lens processing difficulty is low, the process is relatively simple, and the material and processing costs are also significantly reduced.

[0044] In this invention, the lens group includes a first lens group and a second lens group, wherein the first lens group is composed of a first lens 1, and the second lens group is composed of a second lens 2 to a seventh lens 7.

[0045] The focal length f1 and center thickness d1 of the first lens 1 satisfy: 8.17≤ |f1 / d1| ≤18.88.

[0046] Specifically, by controlling the |f1 / d1| value within a moderate range, the first lens 1 is ensured to effectively reduce the overall length while maintaining sufficient thickness to guarantee strength and manufacturability. In particular, by limiting the range of |f1 / d1|, this invention ensures that while shortening the overall system length, the first lens 1 has sufficient central thickness to maintain mechanical strength and impact resistance, avoiding lens fragility or poor molding due to excessive pursuit of miniaturization. The focal length and central thickness of the first lens 1 together affect the initial state of spherical aberration, coma, and field curvature. An appropriate ratio can reduce the aberration correction burden on subsequent lenses, thereby achieving high resolution with a smaller number of lenses.

[0047] The effective focal length of the second lens group, namely the combined focal length f02 of the second lens 2 to the seventh lens 7, satisfies the following condition: 2.08 ≤ |f02 / f| ≤ 6.75.

[0048] Specifically, this invention controls the |f02 / f| value within a reasonable range, enabling the combined lens of the second lens 2 to the seventh lens 7 to bear a moderate optical power, effectively shortening the total optical length while ensuring image quality, thus achieving a miniaturized design. By optimizing the ratio of the combined focal length of the second lens 2 to the seventh lens 7 to the system focal length, and working synergistically with the first lens 1, the combined lens possesses sufficient aberration correction capability, effectively balancing coma, astigmatism, and field curvature introduced by the first lens 1, achieving high-resolution imaging across the entire field of view, and simultaneously achieving synergistic optimization of a large field of view and low distortion while effectively converging incident light rays from a large field of view. By limiting the ratio of the combined focal length of the latter group to the system focal length within a specific range, and in addition, working synergistically with the performance limitations of the first lens 1, the optical power distribution of the lens group is more uniform, reducing the sensitivity to the surface shape of individual lenses, and improving the temperature stability and production yield of the lens.

[0049] In this invention, the maximum field of view (FOV) of the anthropomorphic eyepiece lens is 55°.

[0050] In this invention, the anthropomorphic lens satisfies the following conditions: TTL / N ≤ 6.2, and TTL < 43 mm; Where TTL is the distance on the optical axis from the center of the object side of the first lens 1 to the imaging surface of the anthropomorphic eyepiece lens, and N is the number of lenses in the lens group, specifically 7.

[0051] Specifically, by limiting the TTL value, the lens can be integrated into compact devices with strict space constraints, such as smartphones, automotive cameras, and endoscopes, meeting the urgent miniaturization needs of modern consumer electronics and industrial equipment. By limiting the TTL / N value, the axial space of each lens is fully utilized, avoiding problems such as excessively thin lenses, difficult processing, and easy deformation caused by an excessively small TTL / N, and avoiding problems such as volume redundancy and uneven distribution of optical power caused by an excessively large TTL / N. Thus, by rationally allocating positive and negative optical power and aspherical surface shape, a large field of view, high resolution, and low distortion imaging performance can be achieved within a limited total length, while maintaining a high production yield and low cost.

[0052] In this invention, the anthropomorphic lens satisfies: TTL / IH ≤ 2.8; Where TTL is the distance on the optical axis from the center of the object side of the first lens 1 to the imaging surface of the humanoid eyepiece lens, and IH is the maximum effective image circle radius on the imaging surface of the humanoid eyepiece lens.

[0053] Specifically, while achieving a wide field of view, the overall optical length is controlled within a reasonable range, making the lens suitable for applications with strict size requirements, such as smartphones, automotive cameras, and endoscopes.

[0054] In this invention, the anthropomorphic lens satisfies: 1.43 < |TTL / f| < 1.46; Where TTL is the distance on the optical axis from the center of the object side of the first lens 1 to the imaging surface of the humanoid eyepiece, and f is the effective focal length of the humanoid eyepiece.

[0055] Specifically, a reverse telescope structure is used to achieve wide-angle imaging, while the rear group has sufficient optical power to correct coma, astigmatism and distortion introduced by the first lens, so that the system can still achieve high resolution in a compact structure.

[0056] In this invention, the anthropomorphic lens satisfies: 3.41≤|f / EPD|≤ 3.70, and EPD ≥8 mm; Where EPD is the entrance pupil diameter of the anthropomorphic lens, and f is the effective focal length of the anthropomorphic lens.

[0057] Specifically, while ensuring sufficient light transmission, the depth of field is reasonably controlled to achieve the requirements of human-like glasses lenses to simulate natural depth of field, making the imaging effect closer to the human eye's visual experience.

[0058] In summary, the anthropomorphic eyepiece provided by this invention achieves a relatively short overall optical length while maintaining a large entrance pupil diameter, i.e., a large aperture characteristic. This allows the lens to obtain sufficient light intake in limited spaces, such as in applications like drones, smart glasses, and miniature camera modules, making it particularly suitable for high-definition imaging in low-light environments.

[0059] In this invention, at a spatial frequency of 120 lp / mm, the MTF modulation transfer function value of the anthropomorphic eyepiece lens is ≥0.2 across the entire field of view.

[0060] Specifically, the anthropomorphic eyepiece provided by this invention can maintain high resolution at both the center and the edges, meeting the resolution requirements of high-pixel sensors. Combined with the large aperture characteristics, it can achieve high-resolution imaging and output clear and sharp images even in low-light environments.

[0061] In this invention, the anthropomorphic lens satisfies: |Dist| < 0.3%; Where Dist is the optical distortion value of the anthropomorphic lens at its maximum field of view.

[0062] Specifically, distortion is an important evaluation indicator for humanoid eyeglasses. The humanoid eyeglasses provided by this invention achieves extremely low optical distortion across the entire field of view, enabling low-distortion imaging across the entire field of view. It effectively suppresses barrel or pincushion distortion at the edges of the image, making the imaging effect closer to human visual perception. It is suitable for fields with extremely high requirements for realism, such as virtual reality, augmented reality, and bionic vision.

[0063] Traditional large-aperture lenses often exhibit noticeable vignetting at the edges, affecting the viewing experience. The human-eye lens design provided by this invention eliminates vignetting, ensuring uniform brightness in the image and preventing vignetting around the edges. Specifically, by optimizing pupil matching and beam control, it achieves near-ideal high illumination uniformity, ensuring consistent brightness from the center to the edges of the image, further enhancing the realistic human-eye experience.

[0064] In this invention, the first lens 1 includes a first surface located on the object side and a second surface located on the image side; The first surface is an even-order aspherical surface, and the second surface is a spherical surface; An even-order aspherical surface is formed by superimposing a reference sphere and an aspherical polynomial, in which only the 4th, 6th and 8th power terms of the radial coordinate are included.

[0065] Specifically, the sag of an even-order aspherical surface is determined by the following formula: ; Where r is the perpendicular distance from a point on the even-order aspherical surface to the optical axis, z is the sag of the even-order aspherical surface, c is the curvature, k is the conic coefficient, and A4, A6, and A8 are aspherical coefficients, and the second-order term and its aspherical coefficients greater than the eighth order are all 0.

[0066] Specifically, the aspherical polynomial of the even-order aspherical lens used in the first lens 1 only contains the 4th, 6th, and 8th powers of r, and does not contain higher-order terms. This allows the aspherical mold to be machined by standard diamond single-point turning without the need for ultra-precision compensation processes, thus significantly reducing the mold manufacturing cost. At the same time, the three coefficients A4, A6, and A8 form a stepwise aberration correction chain from low to high order. Without the intervention of higher-order terms, high-resolution imaging of the entire field of view is achieved, ensuring good imaging uniformity.

[0067] In this invention, the refractive index Nd1 and its Abbe number Vd1 of the first lens 1 satisfy: 1.55≤ Nd1≤1.61, 60≤Vd1≤68; The refractive index Nd2 and its Abbe number Vd2 of the second lens 2 satisfy: 1.56≤ Nd2≤1.65, 36≤ Vd2≤58; The refractive index Nd3 and its Abbe number Vd3 of the third lens 3 satisfy: 1.75≤ Nd3≤1.81, 22≤ Vd3≤27; The refractive index Nd4 and its Abbe number Vd4 of the fourth lens 4 satisfy: 1.58 ≤ Nd4 ≤ 1.61, 67 ≤ Vd4 ≤ 69; The refractive index Nd5 and Abbe number Vd5 of the fifth lens 5 satisfy: 1.64≤ Nd5≤1.76, 50≤ Vd5≤56; The refractive index Nd6 and Abbe number Vd6 of the sixth lens 6 satisfy: 1.71≤ Nd6≤1.81, 23≤ Vd6≤28; The refractive index Nd7 and Abbe number Vd7 of the seventh lens 7 satisfy: 1.51≤ Nd7≤1.57, 60≤ Vd7≤65.

[0068] The miniaturized, wide-field-of-view, high-resolution, low-distortion humanoid eyeglass lens with an external pupil disclosed in this invention will be further described in detail below with reference to specific embodiments. Unless otherwise specified, the materials used in the embodiments and comparative examples are commercially available.

[0069] Example 1 A miniaturized, wide-field-of-view, high-resolution, low-distortion humanoid eyepiece with an external pupil, as shown in the attached image. Figure 1 As shown, it includes: Apertures and lens groups are arranged sequentially from the object side to the image side.

[0070] The lens group comprises, in sequence, a first lens 1 to a seventh lens 7 with air gaps between them, namely, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6 and a seventh lens 7.

[0071] The first lens 1 is an aspherical lens, and the second lens 2 to the seventh lens 7 are all spherical lenses with optical power; the first lens 1, the fourth lens 4 and the fifth lens 5 have positive optical power, and the second lens 2, the third lens 3, the sixth lens 6 and the seventh lens 7 have negative optical power.

[0072] The specific optical system of the lens group is shown in Table 1, where the first lens 1 to the seventh lens 7 are briefly referred to as lens 1 to lens 7 respectively.

[0073] Table 1. Optical system information for Example 1

[0074] Among them, the distance ST between the aperture stop and the first lens 1 on the optical axis is 8 mm; the entrance pupil diameter EPD of the anthropomorphic lens is 8 mm; the thickness d1 of the first lens 1 is 3.187 mm; the focal length f1 of the first lens 1 is 32.47 mm; the combined focal length f02 of the second lens 2 to the seventh lens 7 is -102.06 mm; the effective focal length f of the anthropomorphic lens is 28.5 mm; and the distance TTL on the optical axis from the center of the object side of the first lens 1 to the imaging surface of the anthropomorphic lens is 41.06 mm.

[0075] As attached Figure 2 Appendix Figure 3 As shown, based on the anthropomorphic eyepiece provided in Embodiment 1, with... Figure 2 The figure shows the MTF curve for the entire field of view. As can be seen, the system's maximum field of view is 55°, and the MTF modulation transfer function value is ≥0.2 across the entire field of view at a spatial frequency of 120 lp / mm. (Attached) Figure 3 The distortion curve is shown in the figure. As can be seen from the figure, the maximum distortion across the entire field of view does not exceed 0.3%. This proves that the anthropomorphic eyepiece provided in Example 1 achieves high-resolution, low-distortion imaging over a large field of view.

[0076] Example 2 A miniaturized, wide-field-of-view, high-resolution, low-distortion humanoid eyepiece with an external pupil, as shown in the attached image. Figure 1 As shown, it includes: Apertures and lens groups are arranged sequentially from the object side to the image side.

[0077] The lens group comprises, in sequence, a first lens 1 to a seventh lens 7 with air gaps between them, namely, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6 and a seventh lens 7.

[0078] The first lens 1 is an aspherical lens, and the second lens 2 to the seventh lens 7 are all spherical lenses with optical power; the first lens 1, the fourth lens 4 and the fifth lens 5 have positive optical power, and the second lens 2, the third lens 3, the sixth lens 6 and the seventh lens 7 have negative optical power.

[0079] The specific optical system of the lens group is shown in Table 2, where the first lens 1 to the seventh lens 7 are briefly referred to as lens 1 to lens 7 respectively.

[0080] Table 2. Optical system information for Example 2

[0081] The distance ST between the aperture stop and the first lens 1 on the optical axis is 8.5 mm; the entrance pupil diameter EPD of the anthropomorphic lens is 8 mm; the thickness d1 of the first lens 1 is 3.632 mm; the focal length f1 of the first lens 1 is 29.68 mm; the combined focal length f02 of the second lens 2 to the seventh lens 7 is -60.23 mm; the effective focal length f of the anthropomorphic lens is 29.0 mm; and the distance TTL on the optical axis from the center of the object side of the first lens 1 to the imaging surface of the anthropomorphic lens is 41.66 mm.

[0082] As attached Figure 4 Appendix Figure 5 As shown, based on the anthropomorphic eyepiece provided in Embodiment 2, with... Figure 4 The figure shows the MTF curve for the entire field of view. As can be seen, the system's maximum field of view is 55°, and the MTF modulation transfer function value is ≥0.2 across the entire field of view at a spatial frequency of 120 lp / mm. (Attached) Figure 5 The distortion curve is shown in the figure. It can be seen from the figure that the maximum distortion across the entire field of view does not exceed 0.3%. This proves that the anthropomorphic eyepiece provided in Example 2 achieves high-resolution, low-distortion imaging over a large field of view.

[0083] Example 3 A miniaturized, wide-field-of-view, high-resolution, low-distortion humanoid eyepiece with an external pupil, as shown in the attached image. Figure 1 As shown, it includes: Apertures and lens groups are arranged sequentially from the object side to the image side.

[0084] The lens group comprises, in sequence, a first lens 1 to a seventh lens 7 with air gaps between them, namely, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6 and a seventh lens 7.

[0085] The first lens 1 is an aspherical lens, and the second lens 2 to the seventh lens 7 are all spherical lenses with optical power; the first lens 1, the fourth lens 4 and the fifth lens 5 have positive optical power, and the second lens 2, the third lens 3, the sixth lens 6 and the seventh lens 7 have negative optical power.

[0086] The specific optical system of the lens group is shown in Table 3, where the first lens 1 to the seventh lens 7 are briefly referred to as lens 1 to lens 7 respectively.

[0087] Table 3. Optical system information for Example 3

[0088] Among them, the distance ST between the aperture stop and the first lens 1 on the optical axis is 9 mm; the entrance pupil diameter EPD of the anthropomorphic lens is 8 mm; the thickness d1 of the first lens 1 is 2.697 mm; the focal length f1 of the first lens 1 is 50.93 mm; the combined focal length f02 of the second lens 2 to the seventh lens 7 is 199.36 mm; the effective focal length f of the anthropomorphic lens is 29.5 mm; and the distance TTL on the optical axis from the center of the object side of the first lens 1 to the imaging surface of the anthropomorphic lens is 42.33 mm.

[0089] As attached Figure 6 Appendix Figure 7 As shown, based on the anthropomorphic eyepiece provided in Embodiment 3, with... Figure 6 The figure shows the MTF curve for the entire field of view. As can be seen, the system's maximum field of view is 55°, and the MTF modulation transfer function value is ≥0.2 across the entire field of view at a spatial frequency of 120 lp / mm. (Attached) Figure 7 The distortion curve is shown in the figure. It can be seen from the figure that the maximum distortion across the entire field of view does not exceed 0.3%. This proves that the anthropomorphic eyepiece provided in Example 3 achieves high-resolution, low-distortion imaging over a large field of view.

[0090] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0091] The foregoing has provided a detailed description of a miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil, as provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A miniaturized, wide-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil, characterized in that, The anthropomorphic lens, from its object side to its image side, comprises: An aperture is used to simulate the pupil of the human eye; The lens group includes a first lens to a seventh lens arranged sequentially from the object side to the image side, and there is an air gap between each adjacent lens; The first lens is an aspherical lens, while the second to seventh lenses are all spherical lenses. The first lens, the fourth lens, and the fifth lens have positive optical power, while the second lens, the third lens, the sixth lens, and the seventh lens have negative optical power. Wherein, the distance ST between the aperture and the first lens on the optical axis is ≥8 mm; The focal length f1 and center thickness d1 of the first lens satisfy: 8.17 ≤ |f1 / d1| ≤ 18.88; The combined focal length f02 of the second lens to the seventh lens and the effective focal length f of the anthropomorphic lens satisfy: 2.08 ≤ |f02 / f| ≤ 6.

75.

2. The miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyeglass lens with an externally positioned pupil as described in claim 1, characterized in that, The maximum field of view (FOV) of the anthropomorphic eyepiece is 55°.

3. The miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil as described in claim 1, characterized in that... The anthropomorphic lens satisfies the following conditions: TTL / N ≤ 6.2, and TTL < 43 mm; Wherein, TTL is the distance on the optical axis from the center of the object side of the first lens to the imaging surface of the anthropomorphic eyepiece, and N is the number of lenses in the lens group.

4. The miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil as described in claim 1, characterized in that... The anthropomorphic lens satisfies: TTL / IH ≤ 2.8; Wherein, TTL is the distance on the optical axis from the center of the object side of the first lens to the imaging surface of the humanoid eyepiece, and IH is the maximum effective image circle radius on the imaging surface of the humanoid eyepiece.

5. A miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil, as described in claim 1, is characterized in that... The anthropomorphic lens satisfies: 1.43 < |TTL / f| < 1.46; Where TTL is the distance on the optical axis from the center of the object side of the first lens to the imaging surface of the humanoid eyepiece, and f is the effective focal length of the humanoid eyepiece.

6. A miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil, as described in claim 1, is characterized in that... The anthropomorphic lens satisfies the following conditions: 3.41 ≤ |f / EPD| ≤ 3.70, and EPD ≥ 8 mm; Wherein, EPD is the entrance pupil diameter of the anthropomorphic lens, and f is the effective focal length of the anthropomorphic lens.

7. A miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil, as described in claim 1, is characterized in that... At a spatial frequency of 120 lp / mm, the MTF modulation transfer function value of the anthropomorphic eyepiece is ≥0.2 across the entire field of view.

8. A miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil, as described in claim 1, is characterized in that... The anthropomorphic lens satisfies: |Dist| < 0.3%; Where Dist is the optical distortion value of the anthropomorphic lens at its maximum field of view.

9. A miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil, as described in claim 1, is characterized in that... The first lens includes a first surface on the object side and a second surface on the image side; The first surface is an even-order aspherical surface, and the second surface is a spherical surface.

10. A miniaturized, large-field-of-view, high-resolution, low-distortion humanoid eyepiece with an externally positioned pupil, as described in claim 1, characterized in that... The refractive index Nd1 and its Abbe number Vd1 of the first lens satisfy: 1.55≤ Nd1≤1.61, 60≤ Vd1≤68; The refractive index Nd2 and its Abbe number Vd2 of the second lens satisfy: 1.56≤ Nd2≤1.65, 36≤ Vd2≤58; The refractive index Nd3 and its Abbe number Vd3 of the third lens satisfy: 1.75≤ Nd3≤1.81, 22≤ Vd3≤27; The refractive index Nd4 and its Abbe number Vd4 of the fourth lens satisfy: 1.58 ≤ Nd4 ≤ 1.61, 67 ≤ Vd4 ≤ 69; The refractive index Nd5 and its Abbe number Vd5 of the fifth lens satisfy: 1.64≤ Nd5≤1.76, 50≤ Vd5≤56; The refractive index Nd6 and its Abbe number Vd6 of the sixth lens satisfy: 1.71≤ Nd6≤1.81, 23≤ Vd6≤28; The refractive index Nd7 and its Abbe number Vd7 of the seventh lens satisfy: 1.51≤ Nd7≤1.57, 60≤ Vd7≤65.

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