Optical lens

Abstract

The utility model discloses an optical lens, which comprises a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens and a sixth lens which are sequentially arranged from an object side to an image side along an optical axis direction, the third lens and the fourth lens are glued to form a doublet lens; the first lens is provided with a convex surface and a concave surface and is installed in the forward direction or the reverse direction. When the first lens is installed in the forward direction, the convex surface faces the object side, and the concave surface faces the image side. When the first lens is reversely installed, the convex surface faces the image side, and the concave surface faces the object side. According to the optical lens, the first lens provided with the convex surface and the concave surface is installed in the forward direction or the reverse direction, the diaphragm and the multiple lenses are combined for cooperative imaging, the optical lens can have at least two imaging effects, standard imaging performance is provided through forward installation, and the conventional photographing requirement is met; the light propagation path is changed through reverse installation, so that background blurring light spots are radially diffused, and a unique out-of-focus bursting effect is formed.

Description

Technical Field

[0001] This utility model relates to the field of optical imaging technology, and in particular to an optical lens. Background Technology

[0002] In the field of optical lenses, as users' demands for diverse imaging effects increase, traditional optical lenses can no longer meet the market's requirements for special visual effects and high-performance imaging. Existing optical lens structures are relatively fixed, resulting in limited imaging effects and lacking the flexibility to achieve special visual effects such as bokeh. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings of existing optical lenses in terms of their limited imaging capabilities and to provide a new type of optical lens.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] This utility model provides an optical lens, comprising: a first lens, a second lens, a third lens, a fourth lens, an aperture stop, a fifth lens, and a sixth lens arranged sequentially from the object side to the image side along the optical axis; the third lens and the fourth lens are cemented together to form a cemented doublet lens; the first lens has a convex surface and a concave surface, and is mounted in a forward or reverse orientation; when the first lens is mounted in a forward orientation, the convex surface faces the object side, and the concave surface faces the image side; when the first lens is mounted in a reverse orientation, the convex surface faces the image side, and the concave surface faces the object side.

[0006] In one embodiment, the focal length of the optical lens is 37mm;

[0007] When the first lens is mounted facing forward, the total optical length of the optical lens is 88mm to 93mm; the distance between the first lens and the second lens is 21.33mm to 28.86mm; the distance between the second lens and the third lens is 2.60mm to 3.52mm; the distance between the fourth lens and the aperture stop is 3.28mm to 4.16mm; the distance between the aperture stop and the fifth lens is 3.14mm to 4.05mm; and the distance between the fifth lens and the sixth lens is 0.085mm to 0.115mm.

[0008] When the first lens is mounted in reverse, the distance between the first lens and the second lens is 5.18 mm to 7.01 mm.

[0009] In one embodiment, the radius of curvature of the convex surface is 48.86 mm to 54.01 mm; the radius of curvature of the concave surface is 25.48 mm to 28.17 mm.

[0010] The second lens has an object-side radius of curvature of 44.81 mm to 49.52 mm and an image-side radius of curvature of -298.76 mm to -270.31 mm.

[0011] The third lens has an object-side radius of curvature of 15.12 mm to 16.71 mm and an image-side radius of curvature of -136.53 mm to -123.53 mm.

[0012] The fourth lens has an object-side radius of curvature of -136.53 mm to -123.53 mm and an image-side radius of curvature of 13.63 mm to 15.07 mm.

[0013] The object-side radius of curvature of the fifth lens is -11.90 mm to -10.76 mm, and the image-side radius of curvature is -14.27 mm to -12.91 mm.

[0014] The object-side radius of curvature of the sixth lens is -423.06 mm to -382.77 mm, and the image-side radius of curvature is -24.76 mm to -22.41 mm.

[0015] In one embodiment, the focal length of the optical lens is 57mm;

[0016] When the first lens is mounted facing forward, the total optical length of the optical lens is 90mm to 94mm; the distance between the first lens and the second lens is 15.30mm to 20.70mm; the distance between the second lens and the third lens is 0.085mm to 0.115mm; the distance between the fourth lens and the aperture stop is 5.98mm to 8.09mm; the distance between the aperture stop and the fifth lens is 4.27mm to 5.78mm; and the distance between the fifth lens and the sixth lens is 0.085mm to 0.115mm.

[0017] When the first lens is mounted in reverse, the distance between the first lens and the second lens is 5.95 mm to 8.05 mm.

[0018] In one embodiment, the radius of curvature of the convex surface is +37.90 mm to +41.89 mm; the radius of curvature of the concave surface is +45.82 mm to +50.65 mm.

[0019] The second lens has an object-side radius of curvature of +30.22 mm to +33.40 mm and an image-side radius of curvature of +81.05 mm to +89.59 mm.

[0020] The third lens has an object-side radius of curvature of +18.05 mm to +19.95 mm and an image-side radius of curvature of +102.68 mm to +113.48 mm.

[0021] The radius of curvature of the object side of the fourth lens is +102.68 mm to +113.48 mm, and the radius of curvature of the image side is +102.68 mm to +113.48 mm.

[0022] The fifth lens has an object-side radius of curvature of -13.28 mm to -12.02 mm and an image-side radius of curvature of -17.55 mm to -15.88 mm.

[0023] The object-side radius of curvature of the sixth lens is -237.27 mm to -214.67 mm, and the image-side radius of curvature is -24.76 mm to -22.41 mm.

[0024] In one embodiment, the first lens has a refractive index of 1.4 to 1.5 and an Abbe number of 70 to 75; the second lens has a refractive index of 1.9 to 2.0 and an Abbe number of 15 to 20; the third lens has a refractive index of 1.5 to 1.6 and an Abbe number of 60 to 65; the fourth lens has a refractive index of 1.9 to 2.0 and an Abbe number of 20 to 25; the fifth lens has a refractive index of 1.9 to 2.0 and an Abbe number of 15 to 20; and the sixth lens has a refractive index of 1.8 to 1.9 and an Abbe number of 45 to 50.

[0025] In one embodiment, the focal length of the optical lens is 77mm;

[0026] When the first lens is mounted facing forward, the distance between the first lens and the second lens is 11.90 mm to 16.10 mm; the distance between the second lens and the third lens is 0.085 mm to 0.115 mm; the distance between the fourth lens and the aperture is 5.11 mm to 6.92 mm; the distance between the aperture and the fifth lens is 1.80 mm to 2.44 mm; and the distance between the fifth lens and the sixth lens is 4.51 mm to 6.11 mm.

[0027] When the first lens is mounted in reverse, the total optical length of the optical lens is 84mm to 88mm, and the distance between the first lens and the second lens is 4.25mm to 5.75mm.

[0028] In one embodiment, the radius of curvature of the convex surface is +28.77 mm to +31.80 mm;

[0029] The radius of curvature of the concave surface is +32.90 mm to +36.37 mm;

[0030] The second lens has an object-side radius of curvature ranging from +29.30 mm to +32.39 mm and an image-side radius of curvature ranging from +90.16 mm to +99.65 mm.

[0031] The third lens has an object-side radius of curvature of +16.53 mm to +18.27 mm and an image-side radius of curvature of +519.28 mm to +573.94 mm.

[0032] The fourth lens has an object-side radius of curvature ranging from +519.28 mm to +573.94 mm and an image-side radius of curvature ranging from +14.14 mm to +15.63 mm.

[0033] The object-side radius of curvature of the fifth lens is -42.52 mm to -38.47 mm, and the image-side radius of curvature is -41.07 mm to -37.16 mm.

[0034] The object-side radius of curvature of the sixth lens is +36.93 mm to +40.82 mm, and the image-side radius of curvature is +43.64 mm to +48.23 mm.

[0035] In one embodiment, the first lens has a refractive index of 1.7 to 1.8 and an Abbe number of 45 to 50; the second lens has a refractive index of 1.8 to 1.9 and an Abbe number of 35 to 40; the third lens has a refractive index of 1.4 to 1.5 and an Abbe number of 80 to 85; the fourth lens has a refractive index of 1.8 to 1.9 and an Abbe number of 30 to 35; the fifth lens has a refractive index of 1.9 to 2.0 and an Abbe number of 30 to 35; and the sixth lens has a refractive index of 1.8 to 1.9 and an Abbe number of 20 to 25.

[0036] In one embodiment, the optical lens further includes an infrared filter located on the side of the sixth lens away from the fifth lens.

[0037] The advantages of the optical lens of this invention compared with the prior art are: by mounting the first lens with convex and concave surfaces in the forward or reverse direction, and combining it with the aperture and multiple lenses to form an image, the optical lens can have at least two imaging effects. The forward mounting provides standard imaging performance to meet the needs of conventional photography; the reverse mounting changes the light propagation path, causing the background blur spot to diffuse radially, forming a unique "bokeh" effect.

[0038] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 A schematic diagram of the structure of an optical lens with a focal length of 37mm when the first lens is in the upright position, provided by this utility model;

[0041] Figure 2 A schematic diagram of the structure of an optical lens with a focal length of 37mm when the first lens is in the reversed position, provided by this utility model;

[0042] Figure 3 A schematic diagram of the structure of an optical lens with a focal length of 57mm when the first lens is in the upright position, provided by this utility model;

[0043] Figure 4 A schematic diagram of the structure of an optical lens with a focal length of 57mm when the first lens is in the reversed position, provided by this utility model;

[0044] Figure 5 A schematic diagram of the structure of an optical lens with a focal length of 77mm when the first lens is in the upright position, provided by this utility model;

[0045] Figure 6 This is a schematic diagram of the structure of an optical lens with a focal length of 77mm when the first lens is in the reversed position, as provided by this utility model.

[0046] 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Aperture stop; 6. Fifth lens; 7. Sixth lens; 8. Infrared filter. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0049] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to 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 this utility model.

[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0051] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0052] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0054] See Figures 1 to 6 As shown, this utility model embodiment provides an optical lens, including: a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, an aperture 5, a fifth lens 6, and a sixth lens 7 arranged sequentially from the object side to the image side along the optical axis; the third lens 3 and the fourth lens 4 are cemented together to form a cemented doublet lens; the first lens 1 has a convex surface and a concave surface, and is installed in a forward or reverse orientation; when the first lens 1 is installed in a forward orientation, the convex surface faces the object side and the concave surface faces the image side; when the first lens 1 is installed in a reverse orientation, the convex surface faces the image side and the concave surface faces the object side.

[0055] Specifically, the core innovation of this solution lies in constructing a collaborative optical architecture of a six-element lens group and an aperture stop 5. The bidirectional reversible mounting design of the first lens 1 enables multi-functional imaging with a single lens. The third lens 3 and the fourth lens 4 are cemented together to form a cemented doublet lens, utilizing the complementary properties of high / low dispersion materials to suppress chromatic aberration. The aperture stop 5 is positioned between the fourth lens 4 and the fifth lens 6, precisely controlling the incident angle of edge rays. The convex and concave design of the first lens 1 allows it to be mounted in either the forward or reverse orientation, enabling switching of imaging styles by changing the initial refraction direction of the light path.

[0056] After light enters from the object side, it first undergoes primary modulation by the first lens 1: when mounted facing forward (convex side towards the object), the light converges smoothly; when mounted facing backward (concave side towards the object), the light diverges. The beam then passes through the second lens 2 to correct field curvature, and a cemented doublet eliminates axial chromatic aberration. After the aperture stop 5 filters the effective imaging beam, the fifth lens 6 compresses the image-side aperture angle, and the sixth lens 7 suppresses edge distortion, ultimately forming a clear image point on the image plane.

[0057] This structure breaks through the unidirectional optical path limitation of traditional lenses. Forward mounting provides standard imaging performance, meeting the resolution and contrast requirements of conventional photography; reverse mounting alters the light propagation path in the out-of-focus area, causing radial diffusion of the background blur spots, creating a unique "bokeh" effect. The cemented doublet lens significantly reduces focus drift for multi-wavelength light, and the rear-positioned 5-stop design reduces stray light interference within the lens barrel, improving image purity in low-light environments.

[0058] In one embodiment, the focal length of the optical lens is 37mm;

[0059] When the first lens 1 is mounted facing forward, the total optical length of the optical lens is 88mm to 93mm; the distance between the first lens 1 and the second lens 2 is 21.33mm to 28.86mm; the distance between the second lens 2 and the third lens 3 is 2.60mm to 3.52mm; the distance between the fourth lens 4 and the aperture 5 is 3.28mm to 4.16mm; the distance between the aperture 5 and the fifth lens 6 is 3.14mm to 4.05mm; and the distance between the fifth lens 6 and the sixth lens 7 is 0.085mm to 0.115mm.

[0060] When the first lens 1 is mounted in reverse, the distance between the first lens 1 and the second lens 2 is 5.18 mm to 7.01 mm.

[0061] Specifically, for the 37mm focal length requirement at the wide-angle end, this embodiment balances the field of view and aberrations by precisely controlling the lens spacing. When the first lens 1 is mounted upright, the large spacing of 21.33 to 28.86mm forms the negative optical power distribution of the front group, expanding the edge field of view coverage; the front and rear spacing of the aperture stop 5 (3.28 to 4.16mm and 3.14 to 4.05mm) limits the incident light cone angle and suppresses coma; the fifth and sixth lenses, with a macro spacing of 70.085 to 0.115mm, form a quasi-concentric system to correct astigmatism.

[0062] When mounted upright, the convex surface of the first lens 1 (radius of curvature 48.86 to 54.01 mm) smoothly converges the light, while the long-spacing design allows the second lens 2 to receive the diverging beam. In the cemented doublet, the combination of the strong positive optical power of the third lens 3 (radius of curvature 15.12 to 16.71 mm) and the negative optical power of the fourth lens 4 (radius of curvature -136.53 to -123.53 mm) cancels out chromatic aberration. The large negative curvature image-side surface of the sixth lens 7 (-382.77 to -423.06 mm) suppresses edge distortion.

[0063] Achieving an ultra-wide field of view with a compact overall length of 88 to 93 mm and minimal edge illumination attenuation. When mounted in reverse, the short spacing of 5.18 to 7.01 mm forces light divergence from the concave surface of the first lens 1, resulting in starburst-shaped diffraction fringes for out-of-focus point sources. The cemented doublet lens keeps second-order spectral shift to an extremely low level, giving the optical lens excellent chromatic aberration correction capabilities.

[0064] In one embodiment, the radius of curvature of the convex surface is from 48.86 mm to 54.01 mm; the radius of curvature of the concave surface is from 25.48 mm to 28.17 mm.

[0065] The object-side radius of curvature of the second lens 2 is 44.81 mm to 49.52 mm, and the image-side radius of curvature is -298.76 mm to -270.31 mm.

[0066] The object-side radius of curvature of the third lens 3 is 15.12 mm to 16.71 mm, and the image-side radius of curvature is -136.53 mm to -123.53 mm.

[0067] The radius of curvature of the object side of the fourth lens 4 is -136.53 mm to -123.53 mm, and the radius of curvature of the image side is 13.63 mm to 15.07 mm.

[0068] The radius of curvature of the object side of the fifth lens 6 is -11.90 mm to -10.76 mm, and the radius of curvature of the image side is -14.27 mm to -12.91 mm.

[0069] The object-side radius of curvature of the sixth lens 7 ranges from -423.06 mm to -382.77 mm, and the image-side radius of curvature ranges from -24.76 mm to -22.41 mm.

[0070] Specifically, this scheme improves wide-angle optical performance through the synergistic optimization of the curvature of each lens: the curvature ratio of the convex to concave surfaces of the first lens 1 (48.86 to 54.01 mm / 25.48 to 28.17 mm) controls primary spherical aberration; the positive curvature of the object side of the second lens 2 (44.81 to 49.52 mm) and the large negative curvature of the image side (-298.76 to -270.31 mm) are combined to correct the field curvature; and the double negative curvature design of the fifth lens 6 (-11.90 to -10.76 mm / -14.27 to -12.91 mm) compresses the image-side light cone angle.

[0071] When light passes through the convex surface of the first lens 1, it undergoes gentle refraction, and the concave surface provides secondary modulation to reduce spherical aberration. The large radius of curvature on the image-side surface of the second lens 2 causes peripheral rays to bend inward, compensating for off-axis astigmatism. The fifth lens 6 has a strong negative optical power to reduce the beam diameter, and the sixth lens 7 has an extremely large negative curvature on the object-side surface (-423.06 to -382.77 mm) to eliminate barrel distortion.

[0072] This embodiment significantly reduces the distortion rate of the optical lens and substantially reduces the edge resolution attenuation rate. When mounted in reverse, the negative spherical aberration generated by the concave surface (radius of curvature of 25.48 to 28.17 mm) couples with the 6th field curvature of the fifth lens, causing the diameter of the background blur spot to increase and exhibit a radial texture.

[0073] In one embodiment, the focal length of the optical lens is 57mm;

[0074] When the first lens 1 is mounted facing forward, the total optical length of the optical lens is 90mm to 94mm; the distance between the first lens 1 and the second lens 2 is 15.30mm to 20.70mm; the distance between the second lens 2 and the third lens 3 is 0.085mm to 0.115mm; the distance between the fourth lens 4 and the aperture 5 is 5.98mm to 8.09mm; the distance between the aperture 5 and the fifth lens 6 is 4.27mm to 5.78mm; and the distance between the fifth lens 6 and the sixth lens 7 is 0.085mm to 0.115mm.

[0075] When the first lens 1 is installed in reverse, the distance between the first lens 1 and the second lens 2 is 5.95 mm to 8.05 mm.

[0076] Specifically, this scheme achieves a 57mm focal length transition through optical power redistribution: when the first lens 1 is mounted upright, a spacing of 15.30 to 20.70mm forms a front group with medium negative optical power; the cemented doublet lens adopts a symmetrical curvature design (102.68 to 113.48mm) to eliminate field curvature asymmetry; the aperture 5 is moved back (64.27 to 5.78mm from the fifth lens) to expand the effective light transmission aperture.

[0077] When mounted upright, the convex surface of the first lens 1 (37.90 to 41.89 mm) and the positive curvature object-side surface of the second lens 2 (30.22 to 33.40 mm) form a converging cone. The equal curvature design of the cemented doublet lenses ensures symmetrical bending of the optical path, eliminating oblique astigmatism. The strong negative optical power of the fifth lens 6 (-12.02 to -13.28 mm) and the negative curvature image-side surface of the sixth lens 7 (-22.41 to -24.76 mm) form a telecentric structure.

[0078] A large F / 2.0 aperture is achieved with an overall length of 90 to 94 mm, reducing focal plane shift. When mounted in reverse, the negative spherical aberration generated by the concave surface of the first lens 1 (45.82 to 50.65 mm) couples with the positive field curvature of the fifth lens 6, blurring the background to form a vortex-like bokeh, and the light spots in the transition area exhibit a dynamic blur effect.

[0079] In one embodiment, the radius of curvature of the convex surface is +37.90 mm to +41.89 mm; the radius of curvature of the concave surface is +45.82 mm to +50.65 mm.

[0080] The object-side radius of curvature of the second lens 2 is +30.22 mm to +33.40 mm, and the image-side radius of curvature is +81.05 mm to +89.59 mm.

[0081] The object-side radius of curvature of the third lens 3 is +18.05 mm to +19.95 mm, and the image-side radius of curvature is +102.68 mm to +113.48 mm.

[0082] The radius of curvature of the object side of the fourth lens 4 is +102.68 mm to +113.48 mm, and the radius of curvature of the image side is +102.68 mm to +113.48 mm.

[0083] The radius of curvature of the object side of the fifth lens 6 is -13.28 mm to -12.02 mm, and the radius of curvature of the image side is -17.55 mm to -15.88 mm.

[0084] The object-side radius of curvature of the sixth lens 7 is -237.27 mm to -214.67 mm, and the image-side radius of curvature is -24.76 mm to -22.41 mm.

[0085] Specifically, the double-cemented lens in this design has a consistent curvature on both the object and image sides (102.68 to 113.48 mm), achieving a zero-field curvature design; the sixth lens 7 has an ultra-large negative curvature on the object side (-237.27 to -214.67 mm) to suppress chromatic aberration at magnification; the first lens 1 has a concave curvature (45.82 to 50.65 mm) and a convex curvature (37.90 to 41.89 mm), reserving optical correction space for reverse mounting.

[0086] Light rays maintain stable propagation direction when passing through symmetrical cemented doublet lenses, avoiding the accumulation of off-axis aberrations. The fifth lens (6) has a negative curvature on the image side (-15.88 to -17.55 mm) to produce negative distortion to compensate for the positive distortion of the previous group. The sixth lens (7) has strong negative optical power to compress the image-side beam diameter and improve the uniformity of edge illumination.

[0087] This embodiment achieves invisible chromatic aberration correction across the entire field of view, significantly reducing the diameter of the blur spot at large apertures. When mounted in reverse, the concave curvature interacts with the positive optical power of the second lens 2, causing the foreground blurred spot to exhibit a comet tail effect, enhancing the sense of depth in the image.

[0088] In one embodiment, the first lens 1 has a refractive index of 1.4 to 1.5 and an Abbe number of 70 to 75; the second lens 2 has a refractive index of 1.9 to 2.0 and an Abbe number of 15 to 20; the third lens 3 has a refractive index of 1.5 to 1.6 and an Abbe number of 60 to 65; the fourth lens 4 has a refractive index of 1.9 to 2.0 and an Abbe number of 20 to 25; the fifth lens 6 has a refractive index of 1.9 to 2.0 and an Abbe number of 15 to 20; and the sixth lens 7 has a refractive index of 1.8 to 1.9 and an Abbe number of 45 to 50.

[0089] Zero chromatic aberration gradient is achieved by precisely matching the optical constants of the materials: the first lens 1 is made of low-dispersion material (Abbe number 70-75) to suppress short-wavelength focus drift; the second lens 2, the fourth lens 4, and the fifth lens 6 are made of high-refractive-index material (refractive index 1.9-2.0) to compress the system size; in the cemented doublet, the third lens 3 with a high Abbe number (60-65) and the fourth lens 4 with a low Abbe number (20-25) form a dispersion complementary pair.

[0090] At the 37mm wide-angle end, focus drift at the 435nm wavelength is suppressed to an imperceptible level. At the 57mm medium focal length end, the combination of a medium Abbe number (45-50) and a high refractive index (1.8-1.9) in the sixth lens effectively suppresses chromatic aberration caused by large incident angles and effectively eliminates edge chromatic fringing.

[0091] In one embodiment, the focal length of the optical lens is 77mm;

[0092] When the first lens 1 is mounted facing forward, the distance between the first lens 1 and the second lens 2 is 11.90 mm to 16.10 mm; the distance between the second lens 2 and the third lens 3 is 0.085 mm to 0.115 mm; the distance between the fourth lens 4 and the aperture 5 is 5.11 mm to 6.92 mm; the distance between the aperture 5 and the fifth lens 6 is 1.80 mm to 2.44 mm; and the distance between the fifth lens 6 and the sixth lens 7 is 4.51 mm to 6.11 mm.

[0093] When the first lens 1 is mounted in reverse, the total optical length of the optical lens is 84mm to 88mm, and the distance between the first lens 1 and the second lens 2 is 4.25mm to 5.75mm.

[0094] A 77mm telephoto lens is achieved using an anti-reverse telescope structure: the positive optical power of the first lens 1 (radius of curvature from 28.77 to 31.80 mm) and the positive curvature image side surface of the sixth lens 7 (43.64 to 48.23 mm) extend the back intercept; the aperture 5 is moved forward (from 45.11 to 6.92 mm to the fourth lens) to compress the incident light cone angle; the large distance between the fifth and sixth lenses (74.51 to 6.11 mm) forms an air lens to correct the image plane curvature.

[0095] When mounted upright, the second lens 2 and the third lens 3 are arranged at a micro-distance (0.085 to 0.115 mm) to form a compound achromatic group. The fourth lens 4 in the cemented doublet has a strong positive optical power (14.14 to 15.63 mm) to compensate for the spherical aberration of the preceding group. The fifth lens 6 has a negative optical power, and the sixth lens 7 has a positive optical power, which together balance the Petzval sum.

[0096] A super-large aperture of F / 1.8 is achieved with an overall length of 84 to 88 mm, extending the depth of focus to 1.8 times that of conventional designs. When mounted in reverse, the short distance of 4.25 to 5.75 mm causes barrel distortion on the concave surface of the first lens 1 (32.90 to 36.37 mm), resulting in annular diffraction away from the focal light source and a significant improvement in the sharpness gradient of the bokeh transition zone.

[0097] In one embodiment, the radius of curvature of the convex surface is from +28.77 mm to +31.80 mm;

[0098] The radius of curvature of the concave surface ranges from +32.90 mm to +36.37 mm;

[0099] The object-side radius of curvature of the second lens 2 is +29.30 mm to +32.39 mm, and the image-side radius of curvature is +90.16 mm to +99.65 mm.

[0100] The object-side radius of curvature of the third lens 3 is +16.53 mm to +18.27 mm, and the image-side radius of curvature is +519.28 mm to +573.94 mm.

[0101] The radius of curvature of the object side of the fourth lens 4 is +519.28 mm to +573.94 mm, and the radius of curvature of the image side is +14.14 mm to +15.63 mm.

[0102] The radius of curvature of the object side of the fifth lens 6 is -42.52 mm to -38.47 mm, and the radius of curvature of the image side is -41.07 mm to -37.16 mm.

[0103] The object-side radius of curvature of the sixth lens 7 is +36.93 mm to +40.82 mm, and the image-side radius of curvature is +43.64 mm to +48.23 mm.

[0104] The third lens 3 has an ultra-large radius of curvature on its image side (519.28 to 573.94 mm) to reduce sensitivity; the fourth lens 4 inherits this curvature on its object side to achieve a smooth transition in the optical path; the fifth lens 6 has double negative curvature (-38.47 to -42.52 mm / -37.16 to -41.07 mm) to form an astigmatism correction group; the sixth lens 7 has double positive curvature (36.93 to 40.82 mm / 43.64 to 48.23 mm) to achieve telecentric imaging.

[0105] The third lens (3) features an approximately planar design to reduce the impact of manufacturing tolerances. The fourth lens (4) has a small curvature image side surface (14.14 to 15.63 mm) that generates strong converging force. The fifth lens (6) uses air gaps to create a negative lens effect to compensate for field curvature. The sixth lens (7) has positive optical power to output a parallel beam.

[0106] This embodiment achieves the highest MTF value across the entire focal length range and maintains a high contrast ratio at a spatial frequency of 200 lp / mm. When mounted in reverse, the concave curvature combined with the telephoto characteristics creates an axial stretching effect on the foreground bokeh, resulting in a unique "out-of-focus tunnel" visual experience.

[0107] In one embodiment, the first lens 1 has a refractive index of 1.7 to 1.8 and an Abbe number of 45 to 50; the second lens 2 has a refractive index of 1.8 to 1.9 and an Abbe number of 35 to 40; the third lens 3 has a refractive index of 1.4 to 1.5 and an Abbe number of 80 to 85; the fourth lens 4 has a refractive index of 1.8 to 1.9 and an Abbe number of 30 to 35; the fifth lens 6 has a refractive index of 1.9 to 2.0 and an Abbe number of 30 to 35; and the sixth lens 7 has a refractive index of 1.8 to 1.9 and an Abbe number of 20 to 25.

[0108] The first lens 1 has medium dispersion (Abbe number 45-50) to balance spherical aberration and chromatic aberration; the third lens 3 has ultra-low dispersion (Abbe number 80-85) to suppress secondary spectrum; the fifth lens 6 has high refractive index (1.9-2.0) and medium Abbe number (30-35) to improve field curvature correction efficiency.

[0109] At a large aperture of F / 1.8, the focus drift at a long wavelength of 700nm is suppressed to a level imperceptible to the human eye. When mounted in reverse, the material properties of the first lens 1 and its concave design work together to create a rainbow-colored halo effect in the out-of-focus area.

[0110] In one embodiment, the optical lens further includes an infrared filter 8, which is located on the side of the sixth lens 7 away from the fifth lens 6.

[0111] In this embodiment, an infrared filter 8 is added to the optical lens, located on the side of the sixth lens 7 away from the fifth lens 6. This effectively blocks infrared light from entering, avoiding color casts and blurring caused by infrared interference, thus ensuring true-to-life colors and clear images. Especially in complex lighting environments, it significantly improves image quality, making the lens suitable for shooting scenarios with high color reproduction requirements, and enhancing the applicability and imaging stability of the optical lens.

[0112] Please refer to Tables 1 and 2 below. Table 1 shows the parameters of the first lens 1 in a group of optical lenses with a focal length of 37mm when mounted upright, and Table 2 shows the parameters of the first lens 1 in a group of optical lenses with a focal length of 37mm when mounted in reverse. Face numbers 1, 3, 5, 6, 9, 11, and 13 represent the object-side faces of the first lens 1, second lens 2, third lens 3, fourth lens 4, fifth lens 6, sixth lens 7, and infrared filter 8, respectively. Face numbers 2, 4, 7, 8, 10, 12, and 14 represent the image-side faces of the first lens 1, second lens 2, fourth lens 4, aperture 5, fifth lens 6, sixth lens 7, and infrared filter 8, respectively. All the specific parameters meet all the above parameter requirements necessary for an optical lens with a focal length of 37mm.

[0113] Face number radius of curvature Thickness / Gap Material refractive index Abbe number surface infinity Infinity 1 51.436251 2 1.48749 70.440487 2 26.825805 25.099308 3 47.164946 2.89702 1.92286 18.895887 4 -284.535017 3.058237 5 15.918218 3.855344 1.58913 61.253571 6 -130.029634 2.818025 1.92286 20.879915 7 14.350022 3.862247 8 infinity 3.696028 9 -11.328804 2.521326 1.92286 18.895887 10 -13.586262 0.1 11 -402.91737 3.242464 1.804 46.574487 12 -23.617204 5.496 13 infinity 2 1.5168 64.198732 14 infinity 30 Image infinity

[0114] Table 1

[0115]

[0116]

[0117] Table 2

[0118] When the 37mm focal length optical lens is in its upright position, lenses 1 through 7 are sequentially arranged along the incident light path, with lens 3 and lens 4 cemented together. Lens 1 has an object-side radius of curvature of 51.436251, a refractive index of 1.48749, and an Abbe number of 70.440487. This lens, combined with subsequent lenses, forms a specific optical power distribution. When light is incident, lens 1 first converges the light, and then, in conjunction with subsequent high-refractive-index lenses (e.g., greater than 1.9) to correct aberrations (at least three lenses with refractive indices greater than 1.9 effectively control spherical aberration and other aberrations), and cemented doublet lenses to compensate for chromatic aberration (at least one lens with an Abbe number of 70 to 75, and at least two with Abbe numbers of 15 to 20), the total optical length of the entire optical lens is controlled within the range of 88 to 93 mm when focusing at infinity, ultimately achieving a standard imaging effect with a 37mm focal length. Its performance is characterized by clear and sharp imaging, natural and smooth out-of-focus transitions, conforming to the actual shooting characteristics of traditional lenses, uniform relative illumination curve, lateral chromatic aberration and distortion controlled within a reasonable range, and MTF curve showing balanced imaging performance at various spatial frequencies, making it suitable for conventional film and television shooting scenarios.

[0119] When the 37mm focal length optical lens is in reverse mounting, the radius of curvature of the object-side surface of the first lens 1 along the incident direction of the light path becomes -26.825805, meaning the first lens 1 is mounted in reverse relative to its upright mounting state. At this time, the effect of the first lens 1 on the incident light changes from converging to diverging, disrupting the balanced optical power distribution as in the upright mounting state. Although subsequent lenses (such as cemented lenses and high-refractive-index lenses) still adjust the light, the reverse mounting of the first lens 1 causes a change in the initial deflection direction of the light path, resulting in a significant change in the way light diffuses in the out-of-focus area—the originally uniform out-of-focus blur spot transforms into a radially "exploded" effect. In this state, the optical lens maintains a total focal length of 37mm through the synergistic effect of the radii of curvature of each lens (e.g., the radius of curvature of surface number 2 becomes -51.436251), thickness spacing (e.g., the thickness / spacing of surface number 2 becomes 6.099308), and material parameters. Its appearance is as follows: the out-of-focus point light source presents a starburst diffusion, and the edge has a unique radial texture, which contrasts sharply with the soft out-of-focus of the front view, providing a visually striking effect with artistic tension for film and television creation. It is especially suitable for shooting scenarios that require highlighting creative expression of out-of-focus, filling the gap in the market for 37mm focal length optical lenses that have different imaging effects for front and rear views.

[0120] This 37mm short-focal-length optical lens achieves dual imaging modes through reversible mounting, combining practicality and creativity within the short-focal-length category. On one hand, when mounted upright, it utilizes the wide field of view and large depth of field of its short focal length to meet the needs of conventional shooting such as documentary and landscape photography, while keeping the total optical length under 93mm, balancing portability and image quality. On the other hand, when mounted in reverse, the synergy between the short-focal-length structure and the inverted lens creates an artistic effect of bokeh explosion, filling a market gap. Technically, it employs a standard spherical lens and cemented doublet technology, combined with high refractive index (>1.9) and specific Abbe numbers (70-75, 15-20) material selection, achieving aberration optimization while reducing costs. Suitable for various shooting scenarios such as film and television, and social media, it demonstrates the advantages of short-focal-length lenses in terms of functional integration and cost-effectiveness.

[0121] Please refer to Tables 3 and 4 below. Table 3 shows the parameters of the first lens 1 in a group of optical lenses with a focal length of 57mm when mounted upright, and Table 4 shows the parameters of the first lens 1 in a group of optical lenses with a focal length of 57mm when mounted in reverse. Face numbers 1, 3, 5, 6, 9, 11, and 13 represent the object-side faces of the first lens 1, second lens 2, third lens 3, fourth lens 4, fifth lens 6, sixth lens 7, and infrared filter 8, respectively. Face numbers 2, 4, 7, 8, 10, 12, and 14 represent the image-side faces of the first lens 1, second lens 2, fourth lens 4, aperture 5, fifth lens 6, sixth lens 7, and infrared filter 8, respectively. All the specific parameters meet all the above parameter requirements necessary for an optical lens with a focal length of 57mm.

[0122]

[0123]

[0124] Table 3

[0125] Face number radius of curvature Thickness / Gap Material refractive index Abbe number surface infinity infinity 1 -48.233405 4.82 1.48749 70.440487 2 -39.897616 7 3 31.809023 3.13 1.92286 18.895887 4 85.319243 0.1 5 19.004567 4.13 1.58913 61.253571 6 108.080669 4 1.92286 20.879915 7 13.482095 7.034692 8 infinity 5.025274 9 -12.648804 3.06 1.92286 18.895887 10 -16.718103 0.1 11 -225.972194 4.1 1.804 46.574487 12 -23.584398 5.5125 13 infinity 2 1.5168 64.198732 14 infinity 31.502586 Image infinity

[0126] Table 4

[0127] When the 57mm focal length optical lens is in its upright mounting state, the first lens 1 to the sixth lens 7, arranged sequentially along the incident light path, have an object-side surface curvature radius of 39.897616. Their structural parameters ensure that light, after refraction by the first lens 1, propagates along a conventional path. This, combined with the subsequent second lens 2, third lens 3 (cemented with the fourth lens 4), variable aperture 5, fifth lens 6, and sixth lens 7, forms an optical path consistent with the actual shooting effect of a conventional lens. At this time, the overall optical power distribution of the lens results in a smooth and uniform distribution of light diffusion spots in the out-of-focus area, achieving the soft bokeh effect characteristic of conventional lenses. In this upright mounting state, the focal length of the optical lens is strictly maintained at 57mm, suitable for film and television and social media shooting scenarios with conventional image quality requirements, meeting the demands for image sharpness and natural bokeh transitions in everyday shooting.

[0128] When the 57mm focal length optical lens is reversed, the radius of curvature of the object-side surface of the first lens 1 becomes -48.233405. This structural reversal fundamentally changes the angle of refraction when light enters the first lens 1, thus affecting the overall optical lens's power distribution and light convergence path. This structural change causes the bokeh in the out-of-focus area to no longer be uniformly distributed after passing through the subsequent lens group, but instead to exhibit a radial outward diffusion pattern, creating a unique "bokeh explosion" visual effect. Although the first lens 1 is reversed, the optical lens can still maintain a focal length of 57mm through parameter matching of the subsequent lens group (such as the coordinated design of the radius of curvature, material refractive index, and dispersion value of each lens). This reversed mounting is suitable for shooting scenarios requiring special artistic expression, adding creative visual elements to the image through the unique shape of the out-of-focus area, filling the gap in the market for medium telephoto lenses that combine conventional and creative out-of-focus effects.

[0129] Please refer to Tables 5 and 6 below. Table 5 shows the parameters of the first lens 1 in a group of optical lenses with a focal length of 77mm when mounted upright, and Table 6 shows the parameters of the first lens 1 in a group of optical lenses with a focal length of 77mm when mounted in reverse. Face numbers 1, 3, 5, 6, 9, 11, and 13 represent the object-side faces of the first lens 1, second lens 2, third lens 3, fourth lens 4, fifth lens 6, sixth lens 7, and infrared filter 8, respectively. Face numbers 2, 4, 7, 8, 10, 12, and 14 represent the image-side faces of the first lens 1, second lens 2, fourth lens 4, aperture 5, fifth lens 6, sixth lens 7, and infrared filter 8, respectively. All the specific parameters meet all the above parameter requirements necessary for an optical lens with a focal length of 77mm.

[0130]

[0131]

[0132] Table 5

[0133]

[0134]

[0135] Table 6

[0136] When a 77mm focal length optical lens is mounted in its upright position, lenses 1 through 7 are sequentially arranged along the incident light path. The object-side radius of curvature of lens 1 is 30.284213. This curvature configuration ensures that after light is refracted by lens 1, it forms a coordinated optical path with the subsequent lenses 2, 3 (cemented with lens 4), 6, and 7. Through reasonable matching of the refractive indices of each lens material (e.g., 1.7433 for lens 1, 1.883 for lens 3) and dispersion values, combined with the luminous flux control of the variable aperture 5, the entire optical lens achieves a 77mm focal length imaging effect when focusing at infinity. The resulting image exhibits the characteristics of a conventional lens in actual shooting: uniform and soft bokeh, uniform image plane illumination distribution (as shown in the upright relative illumination curve), lateral chromatic aberration and optical distortion controlled within the normal range, and an MTF curve demonstrating resolution characteristics consistent with a telephoto lens. This makes it suitable for film and television shooting scenarios with conventional imaging requirements.

[0137] When the 77mm focal length optical lens is in reverse mounting, the first lens 1 is mounted in reverse with an object-side surface curvature radius of -34.636367, changing the initial refraction angle and path of the light. Due to the reversed configuration of the first lens 1, the interaction between the light and subsequent lenses after refraction is altered, resulting in differences in the light diffusion characteristics in the out-of-focus area. Although the first lens 1 is reversed, the system focal length is maintained at 77mm through the cemented structure of the third lens 3 and the fourth lens 4, the coordinated correction of the refractive index of each lens material (e.g., maintaining at least three lenses with a refractive index of 1.8 to 1.9), and the Abbe number (e.g., at least one lens with an Abbe number of 80 to 85), combined with the total optical length controlled at 84mm to 88mm when reversed (for focusing at infinity). Its appearance is characterized by an "explosion" effect in the out-of-focus area, where the out-of-focus blur spots exhibit radial extension characteristics, which is significantly different from the soft blur of the front view. This unique out-of-focus imaging style can meet the needs of special artistic effects in film and television creation. At the same time, parameters such as the relative illumination curve, lateral chromatic aberration, and MTF curve in the reverse view state are still kept within an acceptable range of optical performance, achieving a combination of focal length stability and special imaging effects.

[0138] It is understandable that although this application only describes in detail optical lenses with focal lengths of 37mm, 57mm and 77mm, the structural design consisting of six lenses (including a cemented doublet lens composed of a third lens 3 and a fourth lens 4) and with the first lens 1 being reversible, can be extended to optical lenses with other focal lengths as needed by reasonably adjusting parameters such as the radius of curvature, refractive index, Abbe number and total optical length of each lens, thereby achieving the dual functions of conventional imaging and special bokeh effects.

[0139] The above embodiments are preferred implementations of this utility model. In addition, this utility model can also be implemented in other ways. Any obvious substitutions without departing from the concept of this technical solution are within the protection scope of this utility model.

Claims

1. An optical lens characterized in that, include: A first lens, a second lens, a third lens, a fourth lens, an aperture stop, a fifth lens, and a sixth lens are arranged sequentially from the object side to the image side along the optical axis. The third lens and the fourth lens are cemented together to form a cemented doublet lens. The first lens has a convex surface and a concave surface, and is installed either facing forward or backward. When the first lens is installed forward, the convex surface faces the object side, and the concave surface faces the image side. When the first lens is installed backward, the convex surface faces the image side, and the concave surface faces the object side.

2. The optical lens of claim 1, wherein, The focal length of the optical lens is 37mm; When the first lens is mounted facing forward, the total optical length of the optical lens is 88mm to 93mm; the distance between the first lens and the second lens is 21.33mm to 28.86mm; the distance between the second lens and the third lens is 2.60mm to 3.52mm; the distance between the fourth lens and the aperture stop is 3.28mm to 4.16mm; the distance between the aperture stop and the fifth lens is 3.14mm to 4.05mm; and the distance between the fifth lens and the sixth lens is 0.085mm to 0.115mm. When the first lens is mounted in reverse, the distance between the first lens and the second lens is 5.18 mm to 7.01 mm.

3. The optical lens according to claim 2, characterized in that, The radius of curvature of the convex surface is 48.86 mm to 54.01 mm; the radius of curvature of the concave surface is 25.48 mm to 28.17 mm. The second lens has an object-side radius of curvature of 44.81 mm to 49.52 mm and an image-side radius of curvature of -298.76 mm to -270.31 mm. The third lens has an object-side radius of curvature of 15.12 mm to 16.71 mm and an image-side radius of curvature of -136.53 mm to -123.53 mm. The fourth lens has an object-side radius of curvature of -136.53 mm to -123.53 mm and an image-side radius of curvature of 13.63 mm to 15.07 mm. The object-side radius of curvature of the fifth lens is -11.90 mm to -10.76 mm, and the image-side radius of curvature is -14.27 mm to -12.91 mm. The object-side radius of curvature of the sixth lens is -423.06 mm to -382.77 mm, and the image-side radius of curvature is -24.76 mm to -22.41 mm.

4. The optical lens of claim 1, wherein, The focal length of the optical lens is 57mm; When the first lens is mounted facing forward, the total optical length of the optical lens is 90mm to 94mm; the distance between the first lens and the second lens is 15.30mm to 20.70mm; the distance between the second lens and the third lens is 0.085mm to 0.115mm; the distance between the fourth lens and the aperture stop is 5.98mm to 8.09mm; the distance between the aperture stop and the fifth lens is 4.27mm to 5.78mm; and the distance between the fifth lens and the sixth lens is 0.085mm to 0.115mm. When the first lens is mounted in reverse, the distance between the first lens and the second lens is 5.95 mm to 8.05 mm.

5. The optical lens according to claim 4, characterized in that, The radius of curvature of the convex surface is +37.90 mm to +41.89 mm; the radius of curvature of the concave surface is +45.82 mm to +50.65 mm. The second lens has an object-side radius of curvature of +30.22 mm to +33.40 mm and an image-side radius of curvature of +81.05 mm to +89.59 mm. The third lens has an object-side radius of curvature of +18.05 mm to +19.95 mm and an image-side radius of curvature of +102.68 mm to +113.48 mm. The radius of curvature of the object side of the fourth lens is +102.68 mm to +113.48 mm, and the radius of curvature of the image side is +102.68 mm to +113.48 mm. The fifth lens has an object-side radius of curvature of -13.28 mm to -12.02 mm and an image-side radius of curvature of -17.55 mm to -15.88 mm. The object-side radius of curvature of the sixth lens is -237.27 mm to -214.67 mm, and the image-side radius of curvature is -24.76 mm to -22.41 mm.

6. The optical lens according to claim 3 or 5, characterized in that, The first lens has a refractive index of 1.4 to 1.5 and an Abbe number of 70 to 75; the second lens has a refractive index of 1.9 to 2.0 and an Abbe number of 15 to 20; the third lens has a refractive index of 1.5 to 1.6 and an Abbe number of 60 to 65; the fourth lens has a refractive index of 1.9 to 2.0 and an Abbe number of 20 to 25; the fifth lens has a refractive index of 1.9 to 2.0 and an Abbe number of 15 to 20; and the sixth lens has a refractive index of 1.8 to 1.9 and an Abbe number of 45 to 50.

7. The optical lens of claim 1, wherein, The focal length of the optical lens is 77mm; When the first lens is mounted facing forward, the distance between the first lens and the second lens is 11.90 mm to 16.10 mm; the distance between the second lens and the third lens is 0.085 mm to 0.115 mm; the distance between the fourth lens and the aperture is 5.11 mm to 6.92 mm; the distance between the aperture and the fifth lens is 1.80 mm to 2.44 mm; and the distance between the fifth lens and the sixth lens is 4.51 mm to 6.11 mm. When the first lens is mounted in reverse, the total optical length of the optical lens is 84mm to 88mm, and the distance between the first lens and the second lens is 4.25mm to 5.75mm.

8. The optical lens according to claim 7, characterized in that, The radius of curvature of the convex surface is +28.77 mm to +31.80 mm; The radius of curvature of the concave surface is +32.90 mm to +36.37 mm; The second lens has an object-side radius of curvature ranging from +29.30 mm to +32.39 mm and an image-side radius of curvature ranging from +90.16 mm to +99.65 mm. The third lens has an object-side radius of curvature of +16.53 mm to +18.27 mm and an image-side radius of curvature of +519.28 mm to +573.94 mm. The fourth lens has an object-side radius of curvature ranging from +519.28 mm to +573.94 mm and an image-side radius of curvature ranging from +14.14 mm to +15.63 mm. The object-side radius of curvature of the fifth lens is -42.52 mm to -38.47 mm, and the image-side radius of curvature is -41.07 mm to -37.16 mm. The object-side radius of curvature of the sixth lens is +36.93 mm to +40.82 mm, and the image-side radius of curvature is +43.64 mm to +48.23 mm.

9. The optical lens of claim 8, wherein, The first lens has a refractive index of 1.7 to 1.8 and an Abbe number of 45 to 50; the second lens has a refractive index of 1.8 to 1.9 and an Abbe number of 35 to 40; the third lens has a refractive index of 1.4 to 1.5 and an Abbe number of 80 to 85; the fourth lens has a refractive index of 1.8 to 1.9 and an Abbe number of 30 to 35; the fifth lens has a refractive index of 1.9 to 2.0 and an Abbe number of 30 to 35; and the sixth lens has a refractive index of 1.8 to 1.9 and an Abbe number of 20 to 25.

10. The optical lens of claim 1, wherein, The optical lens also includes an infrared filter, which is located on the side of the sixth lens away from the fifth lens.

Images