Optical telescopic device and multi-pupil eyepiece structure

Abstract

The embodiment of the present application provides an optical telescopic device and a multi-pupil eyepiece structure, the multi-pupil eyepiece structure comprises a first lens group with positive focal length, a second lens group with negative focal length and a third lens group with positive focal length arranged in sequence from an eye observation position to an imaging surface; the first lens group comprises a first lens for converging light; the second lens group comprises a second lens for compensating spherical aberration caused by the first lens group; the third lens group comprises a third lens with positive focal length and a fourth lens with negative focal length, the third lens is used for converging light, and the fourth lens is used for balancing residual aberration; the first lens, the second lens, the third lens and the fourth lens can meet imaging under different exit pupil conditions in multiple configurations.

Description

Technical Field

[0001] This application relates to the field of optical technology, and in particular to an optical telescope and a multi-pupil eyepiece structure. Background Technology

[0002] In the outdoor field, with the development of technology, various optical aiming equipment are constantly being updated and iterated, placing higher demands on optical telescopes used in handheld devices and rifle sights for long-distance, day and night observation and aiming. Among these, optical telescopes play an irreplaceable role as the "eyes" for reconnaissance of targets and enemy activity. The eyepiece, as a basic and crucial component of an optical telescope, amplifies the image formed by the objective lens or the image on various types of displays and emits it as a parallel beam of light to meet the requirements of the human eye for target identification.

[0003] Key optical parameters of an eyepiece include focal length, exit pupil diameter, and exit pupil distance. To meet the observation requirements of the human eye, exit pupil conditions such as exit pupil distance and exit pupil diameter vary considerably depending on the specific application. However, eyepiece designs typically only meet a single requirement, making it impossible for a single eyepiece to satisfy the needs of multiple usage scenarios. Summary of the Invention

[0004] To address the existing technical problems, embodiments of this application provide a multi-pupil eyepiece structure with multiple exit pupils to adapt to multiple usage scenarios, and an optical telescope device including the multi-pupil eyepiece structure.

[0005] To achieve the above objectives, the technical solution of this application embodiment is implemented as follows:

[0006] One aspect of this application provides a multi-pupil eyepiece structure, including a first lens group with a positive focal length, a second lens group with a negative focal length, and a third lens group with a positive focal length arranged sequentially from the human eye observation position to the imaging plane.

[0007] The first lens group includes a first lens for converging light rays;

[0008] The second lens group includes a second lens for compensating for spherical aberration caused by the first lens group;

[0009] The third lens group includes a third lens with a positive focal length and a fourth lens with a negative focal length. The third lens is used to converge light rays, and the fourth lens is used to balance residual aberrations.

[0010] The first lens, the second lens, the third lens, and the fourth lens can satisfy imaging under different exit pupil conditions in multiple configurations.

[0011] In another aspect, this application provides an optical telescope, including the multi-pupil eyepiece structure described in any embodiment of this application, wherein the imaging surface is an OLED display module.

[0012] In another aspect, this application provides an optical telescope, including a telescope tube, an objective lens disposed at the front end of the telescope tube, and a multi-pupil eyepiece structure as described in any embodiment of this application, disposed at the rear end of the telescope tube.

[0013] The multi-pupil eyepiece structure provided in the above embodiments includes a first lens group with a positive focal length, a second lens group with a negative focal length, and a third lens group with a positive focal length, arranged sequentially from the human eye observation position to the imaging plane. The first lens group, the second lens group, and the third lens group form a positive, negative, and positive lens group structure, which can effectively avoid aberrations and facilitate obtaining higher image quality under given configuration conditions. The third lens group is configured to include a third lens and a fourth lens. Based on satisfying the positive, negative, and positive lens group structure, the third lens group with a positive focal length is formed by combining two separate positive and negative lenses. This is beneficial for correcting field curvature and astigmatism, and can increase the variables, making it easier to achieve the goal of obtaining high image quality while simultaneously satisfying multiple given configuration conditions. It also takes into account the correction of off-axis aberrations and aperture spherical aberration under multiple configuration conditions. In this way, the first lens, the second lens, the third lens, and the fourth lens can meet imaging under different exit pupil conditions in multiple configurations. The multi-pupil eyepiece structure has multiple exit pupil conditions, thus adapting to multiple usage scenarios. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the multi-pupil eyepiece structure in one embodiment;

[0015] Figure 2 This is a schematic diagram of the structure of an optical telescope in one embodiment;

[0016] Figure 3 This is a schematic diagram of the optical system of a multi-pupil eyepiece structure under the configuration conditions of an exit pupil diameter of 12mm and an exit pupil distance of 20mm;

[0017] Figure 4 This is a schematic diagram of the optical system of a multi-pupil eyepiece structure under the configuration conditions of an exit pupil diameter of 8mm and an exit pupil distance of 30mm;

[0018] Figure 5 The MTF diagram of a multi-pupil eyepiece structure under the configuration conditions of an exit pupil diameter of 12 mm and an exit pupil distance of 20 mm is shown.

[0019] Figure 6 The MTF diagram of a multi-pupil eyepiece structure under the configuration conditions of an exit pupil diameter of 8 mm and an exit pupil distance of 30 mm is shown.

[0020] Figure 7 Field curvature distortion diagram of a multi-pupil eyepiece structure under the configuration conditions of an exit pupil diameter of 12 mm and an exit pupil distance of 20 mm;

[0021] Figure 8 The field curvature distortion diagram of a multi-pupil eyepiece structure under the configuration conditions of an exit pupil diameter of 8 mm and an exit pupil distance of 30 mm;

[0022] Figure 9 This is a dot diagram of a multi-pupil eyepiece structure under the configuration conditions of an exit pupil diameter of 12mm and an exit pupil distance of 20mm;

[0023] Figure 10 This is a dot diagram of a multi-pupil eyepiece structure under the configuration conditions of an exit pupil diameter of 8mm and an exit pupil distance of 30mm;

[0024] Figure 11 This is a schematic diagram of the optical telescope device in another embodiment.

[0025] Component symbol explanation:

[0026] 10 human eye observation positions, 20 lens combinations, 21 first lens group, 211 first lens, 22 second lens group, 221 second lens, 23 third lens group, 231 third lens, 232 fourth lens, 25 lens barrel, 27 objective lens, 30 imaging plane, 33 OLED display module Detailed Implementation

[0027] The technical solution of this application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the ways in which the invention may be implemented. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0029] In the description of this invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0030] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] Please refer to the following: Figure 1 and Figure 2 This application provides a multi-pupil eyepiece structure, comprising a first lens group 21 with a positive focal length, a second lens group 22 with a negative focal length, and a third lens group 23 with a positive focal length, arranged sequentially from the human eye observation position 10 to the imaging plane 30; the first lens group 21, the second lens group 22, and the third lens group 23 form a lens assembly 20; the first lens group 21 includes a first lens 211 for converging light; the second lens group 22 includes a second lens 221 for compensating for spherical aberration caused by the first lens group 21; the third lens group 23 includes a third lens 231 with a positive focal length and a fourth lens 232 with a negative focal length, the third lens 231 being used to converge light and the fourth lens 232 being used to balance residual aberrations; the first lens 211, the second lens 221, the third lens 231, and the fourth lens 232 can satisfy imaging under different exit pupil conditions in multiple configurations.

[0032] A positive focal length refers to a focal length that is positive along the direction of light propagation. A lens group with a positive focal length is one that converges light rays and forms a real focal point along the direction of light propagation. A negative focal length refers to a focal length that is negative along the direction of light propagation. A lens group with a negative focal length is one that diverges light rays and forms a virtual focal point along the direction of light propagation. Any lens group can refer to one or more lenses.

[0033] Aberration (also known as chromatic aberration) refers to the discrepancy between the results obtained from tracing non-paraxial rays and paraxial rays in a real optical system, and the deviation from the ideal state of Gaussian optics (first-order approximation theory or paraxial rays). Aberrations are generally classified into spherical aberration, coma, field curvature, astigmatism, distortion, chromatic aberration, and wave aberration. In the embodiments of this application, the optical system refers to an optical system formed by a multi-pupil eyepiece structure. Spherical aberration refers to the circular blur pattern formed on the image plane by rays emanating from an on-axis object point intersecting the optical axis at different angles after passing through the optical system. It is generally measured by the axial distance between the intersection point of the actual ray and the optical axis on the image side and the intersection point of the paraxial ray and the optical axis (i.e., the Gaussian image point). For example, when the object distance L of the on-axis object point is determined, the image point position L' is a function of the aperture angle U, and the difference between the position of the actual image point and the ideal image point.

[0034] The exit pupil refers to the common exit point of the light beam emitted from each point on the object surface after passing through the entire optical system and exiting from the last aperture. The human eye can observe from a position at a set distance from the exit pupil. The exit pupil diameter refers to the diameter of the light beam emitted from the multi-pupil eyepiece structure, which is usually the product of the aperture diameter and the magnification. The exit pupil distance refers to the distance from the vertex of the last surface of the optical system to the intersection of the exit pupil plane and the optical axis, which is the set distance mentioned above. Correspondingly, exit pupil conditions mainly include exit pupil diameter and exit pupil distance. Generally, the larger the exit pupil diameter, the brighter the image field. However, when the exit pupil diameter is larger than the diameter of the human pupil, some light will be wasted because it does not enter the human eye, resulting in a smaller effective aperture of the optical system. Secondly, the distance that the human eye needs to maintain between itself and the eyepiece varies depending on the application scenario of the optical telescope. For example, for eyepieces used in some handheld devices, the human eye is often close to the eyepiece for observation, which requires a small exit pupil distance. However, if the eye is too close to the eyepiece, eyelashes may obstruct observation, and moisture on the eyeball may also cause the eyepiece to become blurry. For eyepieces used in some rifle sights, in order to avoid damage to the human eye from the recoil of the shot, a certain distance needs to be maintained between the human eye and the eyepiece, which requires a large exit pupil distance. However, if the eye is too far away from the eyepiece, there will be dark shadows at the edges during observation, and the field of view will be too small to be suitable for viewing.

[0035] Configuration refers to the process of using tools and methods provided by application software to complete a specific task in an engineering project. Each configuration corresponds to a task. Imaging under one exit pupil condition is considered a task. Imaging under different exit pupil conditions in multiple configurations corresponds to multiple tasks that satisfy imaging under different exit pupil conditions. Satisfying imaging under different exit pupil conditions in multiple configurations means that the image quality of the imaging under the corresponding exit pupil conditions in multiple configurations meets the set requirements. The multi-pupil eyepiece structure forms a positive and negative lens group structure through the first lens 211, the second lens 221, the third lens 231, and the fourth lens 232. It is constructed to satisfy imaging under multiple exit pupil conditions as the tasks of the multi-pupil eyepiece structure, so that the multi-pupil eyepiece structure can meet the usage requirements of exit pupil conditions in different scenarios through a single optical system.

[0036] In the above embodiments, the multi-pupil eyepiece structure includes a first lens group 21 with a positive focal length, a second lens group 22 with a negative focal length, and a third lens group 23 with a positive focal length, arranged sequentially from the human eye observation position 10 to the imaging plane 30. The first lens group 21, the second lens group 22, and the third lens group 23 form a positive, negative, and positive lens group structure, which enables the optical system to effectively avoid aberrations and facilitates obtaining higher image quality under given configuration conditions. Specifically, the third lens group 23 is configured to include a third lens 231 and a fourth lens 232, satisfying the requirements of a positive, negative, and positive lens group. Based on the structural form, a third lens group 23 with a positive focal length is formed by combining two lenses with separate positive and negative lenses. This is beneficial for correcting field curvature and astigmatism, and can increase the variables, making it easier to obtain high image quality under multiple given configuration conditions at the same time. It also takes into account the correction of off-axis aberrations and aperture spherical aberration under multiple configuration conditions. In this way, the first lens 211, the second lens 221, the third lens 231 and the fourth lens 232 can meet the imaging under different exit pupil conditions in multiple configurations. The multi-pupil eyepiece structure has multiple exit pupil conditions, so it can be adapted to multiple usage scenarios.

[0037] Optionally, the first lens 211, the second lens 221, the third lens 231, and the fourth lens 232 can satisfy two imaging states under the first exit pupil condition and the second exit pupil condition; the first exit pupil condition is the first exit pupil diameter and the first exit pupil distance applicable to handheld devices; the second exit pupil condition is the second exit pupil diameter and the second exit pupil distance applicable to rifle sights. Here, "handheld device" refers to a aiming category applicable to ordinary optical instruments, typically referring to an aiming category where the human eye is relatively close to the eyepiece for aiming, and the margin requirement for the exit pupil distance between the human eye and the eyepiece is not high. "Rifle sight" refers to an aiming category applicable to hunting rifles. In this embodiment, the first exit pupil diameter applicable to handheld devices is 12mm, and the first exit pupil distance is 20mm; the second exit pupil diameter applicable to rifle sights is 8mm, and the second exit pupil distance is 30mm. When the distance of the first exit pupil is less than the distance of the second exit pupil, the diameter of the first exit pupil is greater than the diameter of the second exit pupil. When the human eye is relatively closer to the eyepiece for aiming and observation, the larger exit pupil diameter can support the human eye to move within a certain range for observation, so that the optical device with this multi-pupil eyepiece structure can better meet the needs of use in sports scenarios.

[0038] In one optional specific example, the first lens 211 is a biconvex lens, the second lens 221 is a biconcave lens, the third lens 231 is a biconvex lens, and the fourth lens 232 is a meniscus lens, with the concave surface of the meniscus lens facing the third lens 231 and the convex surface facing the imaging plane 30. The focal length f1 of the first lens 211 and the focal length F of the multi-pupil eyepiece structure satisfy 0.60≤f1 / F≤0.77; the focal length f2 of the second lens 221 and the focal length F of the multi-pupil eyepiece structure satisfy -1.21≤f2 / F≤-1.08; the focal length f3 of the third lens 231 and the focal length F of the multi-pupil eyepiece structure satisfy 0.58≤f3 / F≤0.73; and the focal length f4 of the fourth lens 232 and the focal length F of the multi-pupil eyepiece structure satisfy -0.63≤f4 / F≤-0.49. In this embodiment, a multi-pupil eyepiece structure is constructed using a lens combination 20 formed by a biconvex lens, a biconcave lens, a biconvex lens, and a meniscus lens. This allows the optical system to satisfy the structural forms of positive, negative, and positive lens groups. The focal lengths of the biconvex, biconcave, and meniscus lenses are used as variables to ensure that the multi-pupil eyepiece structure satisfies imaging under different exit pupil conditions in multiple reconfiguration states. For example, using a first exit pupil condition with a diameter of 12mm and a distance of 20mm, and a second exit pupil condition with a diameter of 8mm and a distance of 30mm, as input conditions for two reconfiguration states, the output results of the variables determined by the multi-pupil eyepiece structure satisfying the first and second exit pupil conditions are obtained. In the structure, the lens assembly 20, from the first end near the human eye observation position 10 to the second end near the imaging plane 30, sequentially arranges a biconvex lens with a focal length ratio satisfying 0.60≤f1 / F≤0.77, a biconcave lens with a focal length ratio satisfying -1.21≤f2 / F≤-1.08, a biconvex lens with a focal length ratio satisfying 0.58≤f3 / F≤0.73, and a meniscus lens with a focal length ratio satisfying -0.63≤f4 / F≤-0.49. This allows the multi-pupil eyepiece structure to maintain a lightweight design. Furthermore, by combining two separate positive and negative lenses to form a third lens group 23 with a positive focal length, variables can be added. Under the same lens assembly and optical parameters, for the same multi-pupil eyepiece structure, please refer to [reference needed]. Figure 3 and Figure 4 This design aims to achieve the goal of providing an optical system with multiple pupil eyepiece structures that meet the exit pupil conditions in different scenarios. Specifically, the concave surface of the meniscus lens faces the human eye observation position 10, and the convex surface faces the imaging plane 30, so that it can form a third lens group 23 with a positive focal length with the adjacent biconvex lens in front, and can balance the residual aberrations caused by the convergence of off-axis rays by the two biconvex lenses in front.

[0039] Furthermore, the curvature of the convex surface of the first lens 211 facing the human eye observation position 10 is greater than the curvature of the convex surface facing the second lens 221; the curvature of the concave surface of the second lens 221 facing the first lens 211 is greater than the curvature of the concave surface facing the third lens 231; the curvature of the convex surface of the third lens 231 facing the second lens 221 is greater than the curvature of the convex surface facing the fourth lens 232; and the curvature of the concave surface of the fourth lens 232 is greater than the curvature of the convex surface of the fourth lens 232. The first lens 211 has a surface curvature radius of R16.8 on its convex surface facing the human eye observation position 10 and a surface curvature radius of R194.2 on its convex surface facing the second lens 221. The second lens 221 has a surface curvature radius of R37.8 on its concave surface facing the first lens 211 and a surface curvature radius of R168.0 on its concave surface facing the third lens 231. The third lens 231 has a surface curvature radius of R22.3 on its convex surface facing the second lens 221 and a surface curvature radius of R35.1 on its convex surface facing the fourth lens 232. The fourth lens 232 has a surface curvature radius of R12.3 on its concave surface facing the third lens 231 and a surface curvature radius of R48.5 on its convex surface facing the imaging surface 30. In this embodiment, a multi-pupil eyepiece structure is constructed using a lens combination 20 formed by a biconvex lens, a biconcave lens, a biconvex lens, and a meniscus lens. This allows the optical system to satisfy the structural forms of positive, negative, and positive lens groups. Furthermore, the surface curvatures of each of the biconvex, biconcave, and meniscus lenses are used as variables to ensure that the multi-pupil eyepiece structure achieves higher image quality and satisfies imaging under different exit pupil conditions in multiple reassemblies. For example, using a first exit pupil condition with a diameter of 12mm and a distance of 20mm, and a second exit pupil condition with a diameter of 8mm and a distance of 30mm, as input conditions for two reassemblies, the multi-pupil eyepiece structure satisfies the first and second exit pupil conditions. The output results of the variables determined by imaging under exit pupil conditions are as follows: In the multi-pupil eyepiece structure, the lens assembly 20 is arranged sequentially from the first end near the human eye observation position 10 to the second end near the imaging surface 30, with the surface curvature radii of the biconvex lenses being R16.8 and R194.2 respectively; the surface curvature radii of the biconcave lenses being R37.8 and R168.0 respectively; the surface curvature radii of the biconvex lenses being R22.3 and R35.1 respectively; and the surface curvature radii of the meniscus lens being R12.3 and R48.5 respectively. This allows the optical system to maintain a lightweight overall design while achieving higher image quality, and realizes the purpose of the multi-pupil eyepiece structure to meet the usage requirements of exit pupil conditions under different scenarios through a single optical system.

[0040] Optionally, the refractive index of the first lens 211 is 1.55, the refractive index of the second lens 221 is 1.95, the refractive index of the third lens 231 is 1.75, and the refractive index of the fourth lens 232 is 1.95. In this embodiment, a lens combination 20 formed by a biconvex lens, a biconcave lens, a biconvex lens, and a meniscus lens is used to construct a multi-pupil eyepiece structure, so that the optical system can satisfy the structural form of positive, negative, and positive lens groups. The refractive indices of the biconvex lens, the biconcave lens, the biconvex lens, and the meniscus lens are further used as variables. For example, the first exit pupil condition with a first exit pupil diameter of 12mm and a first exit pupil distance of 20mm and the second exit pupil condition with a second exit pupil diameter of 8mm and a second exit pupil distance of 30mm are used as two sets of recurrent condition inputs to obtain the output result of the variables determined by the imaging of the multi-pupil eyepiece structure under the first and second exit pupil conditions. In the multi-pupil eyepiece structure, the lens combination 20 extends from the observation position 10 close to the human eye. The first end of the lens assembly 20, moving towards the second end near the imaging surface 30, is sequentially equipped with a biconvex lens with a refractive index of 1.55, a biconcave lens with a refractive index of 1.95, a biconvex lens with a refractive index of 1.75, and a meniscus lens with a refractive index of 1.95. Furthermore, the lens assembly 20, moving from the first end near the human eye observation position 10 towards the second end near the imaging surface 30, is sequentially equipped with a biconvex lens with an Abbe number of 56.3, a biconcave lens with an Abbe number of 17.8, a biconvex lens with an Abbe number of 52.3, and a meniscus lens with an Abbe number of 17.9. In this way, while maintaining the overall lightweight design of the optical system, it achieves higher image quality and enables the multi-pupil eyepiece structure to meet the exit pupil conditions of different scenarios through a single optical system.

[0041] Optionally, the thickness of the first lens 211 is 6mm, the thickness of the second lens 221 is 1.5mm, the thickness of the third lens 231 is 4mm, and the thickness of the fourth lens 232 is 1mm. In this embodiment, a lens combination 20 formed by a biconvex lens, a biconcave lens, a biconvex lens, and a meniscus lens is used to construct a multi-pupil eyepiece structure. The focal length and surface curvature radius of each lens are used as variables, and the imaging under different exit pupil conditions in multiple configurations is used as input to obtain the output results of each variable, thus achieving the multi-pupil eyepiece structure's ability to meet the exit pupil conditions in different scenarios. Furthermore, from the human eye observation position 10 to the imaging surface 30, the thicknesses of the biconvex lens (6mm), the biconcave lens (1.5mm), the biconvex lens (4mm), and the meniscus lens (1mm) are sequentially arranged. Furthermore, from the human eye observation position 10 to the imaging surface 30, the first lens 211 and the second lens 221 are sequentially arranged. The spacing between the lenses is 2mm, the spacing between the second lens 221 and the third lens 231 is 8mm, the spacing between the third lens 231 and the fourth lens 232 is 3mm, and the spacing between the fourth lens 232 and the imaging plane 30 is 5.8mm. This allows the optical system to maintain a lightweight design while achieving higher image quality. It also enables the multi-pupil eyepiece structure to meet the exit pupil requirements of different scenarios through a single optical system. In addition, by controlling the number of lenses in the optical system and simplifying the structure of the optical system, the overall length of the optical system can be effectively controlled, the system weight can be reduced, and portability can be improved. This allows the multi-pupil eyepiece structure to meet the requirements of miniaturization, lightweighting, and economy in higher precision equipment.

[0042] Optionally, the first lens 211, the second lens 221, the third lens 231, and the fourth lens 232 are made of optical glass and are all spherical lenses. In this embodiment, the surface shape of each lens is spherical, which is beneficial for controlling system tolerances, simplifying assembly, and reducing processing technology and assembly difficulty. Furthermore, the use of glass as the material for each lens, with its high refractive index, helps to shorten the overall system length to meet lighter weight requirements and avoids the problem of image quality degradation caused by temperature fluctuations.

[0043] To gain a more comprehensive understanding of the multi-pupil eyepiece structure provided in this application, the design input is based on the following conditions: clear imaging is achieved under two different states, with an exit pupil distance of 20mm and an exit pupil diameter of 12mm, and an exit pupil distance of 30mm and an exit pupil diameter of 8mm. A lens combination 20, consisting of a biconvex lens, a biconcave lens, a biconvex lens, and a meniscus lens, is used to construct the multi-pupil eyepiece structure, forming positive, negative, and positive lens groups. Optical structural parameters such as the focal length, surface curvature, thickness, and adjacent spacing of the biconvex lens, biconcave lens, biconvex lens, and meniscus lens are used as design variables. The output result is obtained showing that the multi-pupil eyepiece structure can achieve high image quality under the given two different states. The optical structural parameters of the biconvex lens, biconcave lens, biconvex lens, and meniscus lens are shown in Table 1.

[0044] Table 1: Optical Structure Parameters of the Optical System

[0045]

[0046]

[0047] Among them, the magnification of the multi-pupil eyepiece structure is 9×, the focal length is 27mm, the imaging surface 30 refers to the OLED screen with a target surface of 0.39 inches, the light incident direction is the object side close to the human eye observation position 10, the light exit direction is the image side where the OLED screen is located, and the object side imaging beam passes through a biconvex lens, a biconcave lens, a biconvex lens and a meniscus lens in sequence to image onto the OLED screen.

[0048] Please see Figures 5 to 10 Under the optical structural parameters in Table 1 above, the multi-pupil eyepiece structure achieves high image quality for exit pupil distances of 20mm and 12mm and exit pupil diameters of 30mm and 8mm, respectively. Figure 5 and Figure 6 The graph shows the MTF (modulation transfer function) of a multi-pupil eyepiece optical system in two scenarios. MTF reflects the imaging quality of an optical system; the larger the area enclosed by the MTF curve and the x-axis, the smoother the MTF curve transition, and thus the better the imaging quality. The graph shows that in a scenario with an exit pupil diameter of 12mm and an exit pupil distance of 20mm, the MTF for all fields of view is ≥0.15 line pairs (LP) / mm; while in a scenario with an exit pupil diameter of 8mm and an exit pupil distance of 30mm, the MTF for all fields of view is ≥0.38 line pairs (LP) / mm. Figure 7 , Figure 8This diagram shows the field curvature and astigmatism of the optical system with a multi-pupil eyepiece structure. The left side shows the field curvature and astigmatism, while the right side shows the distortion. Field curvature and astigmatism are described using both meridional and sagittal directions and are typically caused by off-axis beams, affecting image quality. The diagram shows that off-axis aberration correction is good, with a maximum field curvature ≤0.1mm, which meets the correction range of the human eye. The human eye cannot perceive distortion ≤5%. As shown in the diagram, the distortion of the optical system with a multi-pupil eyepiece structure is ≤1%, which is very small and meets the requirements for human eye use. Figure 9 , Figure 10 This is a dot plot of an optical system with a multi-pupil eyepiece structure. The dot plot reflects the light convergence of the system. In an optical system, the smaller the RMS (root-mean square granularity) radius of the dot plot, the better the image quality. As can be seen from the figure, in both application scenarios, controlling the RMS radius to within 20µm results in high image quality.

[0049] Thus, the multi-pupil eyepiece structure provided in this application embodiment enables the optical system to maintain a lightweight overall design while simultaneously achieving clear imaging under multiple exit pupil positions and sizes. This breaks through the conventional design for a single application scenario and can adapt to the usage needs of multiple different scenarios. Furthermore, by controlling the number of lenses in the optical system and simplifying the optical system structure, the overall length of the optical system is effectively controlled, the system weight is reduced, and portability is improved, so that the multi-pupil eyepiece structure can meet the requirements of miniaturization, lightweighting, and economy in higher precision equipment.

[0050] It should be noted that the multi-pupil eyepiece structure described in this application embodiment can be applied to various optical telescopes that require target imaging for aiming, such as gun sights, thermal imagers, telescopes and other visual optical instruments, and is not limited here.

[0051] In another aspect, this application provides an optical telescope, including a multi-pupil eyepiece structure as described in any of the foregoing embodiments, wherein the imaging surface is an OLED display module 33. In an optional specific example, the optical telescope is a gun sight device.

[0052] Please see Figure 11 In another aspect, this application also provides an optical telescope, including a lens barrel 25, an objective lens 27 disposed at the front end of the lens barrel 25, and a multi-pupil eyepiece structure as described in any of the preceding embodiments disposed at the rear end of the lens barrel 25. The lens barrel 25 provides support for the installation and fixation of various optical elements, and forms an optical path channel for incident light to pass through for target imaging. In an optional specific example, the optical telescope is a telescope.

[0053] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A multi-pupil eyepiece structure, characterized by, The multi-pupil eyepiece structure comprises, in sequence from an eye observation position (10) to an imaging surface (30), a first lens group (21) with positive focal length, a second lens group (22) with negative focal length, and a third lens group (23) with positive focal length; The first lens group (21) comprises a first lens (211) for converging light rays; The second lens group (22) comprises a second lens (221) for compensating spherical aberration caused by the first lens group (21); The third lens group (23) comprises a third lens (231) with positive focal length and a fourth lens (232) with negative focal length, the third lens (231) is used for converging light rays, and the fourth lens (232) is used for balancing residual aberration; The first lens (211), the second lens (221), the third lens (231), and the fourth lens (232) can meet the imaging under different pupil conditions in multiple configurations; The first lens (211), the second lens (221), the third lens (231), and the fourth lens (232) can meet the imaging in two multiple configurations under a first pupil condition and a second pupil condition; the first pupil condition is a first pupil diameter and a first pupil distance suitable for a handheld device; and the second pupil condition is a second pupil diameter and a second pupil distance suitable for a gunsight device; The focal length f1 of the first lens (211) and the focal length F of the multi-pupil eyepiece structure satisfy 0.60≤f1 / F≤0.77; The focal length f2 of the second lens (221) and the focal length F of the multi-pupil eyepiece structure satisfy -1.21≤f2 / F≤-1.08; The focal length f3 of the third lens (231) and the focal length F of the multi-pupil eyepiece structure satisfy 0.58≤f3 / F≤0.73; The focal length f4 of the fourth lens (232) and the focal length F of the multi-pupil eyepiece structure satisfy -0.63≤f4 / F≤-0.

49.

2. The multi-pupil eyepiece structure of claim 1, wherein The first lens (211) is a biconvex lens, the second lens (221) is a biconcave lens, the third lens (231) is a biconvex lens, and the fourth lens (232) is a meniscus lens, the concave surface of the meniscus lens faces the third lens (231), and the convex surface faces the imaging surface (30).

3. The multi-pupil eyepiece structure of claim 2, wherein The curvature of the convex surface of the first lens (211) facing the eye observation position (10) is greater than the curvature of the convex surface facing the second lens (221); the curvature of the concave surface of the second lens (221) facing the first lens (211) is greater than the curvature of the concave surface facing the third lens (231); the curvature of the convex surface of the third lens (231) facing the second lens (221) is greater than the curvature of the convex surface facing the fourth lens (232); and the curvature of the concave surface of the fourth lens (232) is greater than the curvature of the convex surface of the fourth lens (232).

4. The multi-pupil eyepiece structure of claim 3, wherein The first lens (211) has a surface curvature radius of R16.8 facing the convex surface of the human eye observation site (10) and a surface curvature radius of R194.2 facing the convex surface of the second lens (221); The second lens (221) has a surface curvature radius of R37.8 facing the concave surface of the first lens (211) and a surface curvature radius of R168.0 facing the concave surface of the third lens (231); The third lens (231) has a surface curvature radius of R22.3 facing the convex surface of the second lens (221) and a surface curvature radius of R35.1 facing the convex surface of the fourth lens (232); The fourth lens (232) has a surface curvature radius of R12.3 facing the concave surface of the third lens (231) and a surface curvature radius of R48.5 facing the convex surface of the imaging surface (30).

5. The multi-pupil eyepiece structure of claim 4, wherein The first lens (211) has a refractive index of 1.55, the second lens (221) has a refractive index of 1.95, the third lens (231) has a refractive index of 1.75, and the fourth lens (232) has a refractive index of 1.

95.

6. The multi-pupil eyepiece structure of claim 4, wherein The first lens (211) has a thickness of 6mm, the second lens (221) has a thickness of 1.5mm, the third lens (231) has a thickness of 4mm, and the fourth lens (232) has a thickness of 1mm.

7. The multi-pupil eyepiece structure of any one of claims 1 to 6, wherein, The first lens (211), the second lens (221), the third lens (231), and the fourth lens (232) are made of optical glass and are all spherical lenses.

8. An optical telescopic device, characterized in that The multi-pupil eyepiece structure as claimed in any one of claims 1 to 7, wherein the imaging surface is an OLED display module (33).

9. An optical telescopic device, characterized in that A lens barrel (25), an objective lens (27) arranged at the front end of the lens barrel (2), and the multi-pupil eyepiece structure as claimed in any one of claims 1 to 7 arranged at the rear end of the lens barrel (25).

Images