Deformable lens

Abstract

The invention discloses a deformable lens, which belongs to the field of optical lenses and comprises a first spherical lens group, a second spherical lens group, a first cylindrical lens group, a third spherical lens group, a fourth spherical lens group, a second cylindrical lens group, a fifth spherical lens group and an aspherical lens group. The focal lengths of all the lens groups meet the following conditions: 1.3 lt; f (G1-G8) Y / f (G1-G8) Xlt; 1.8); -7.8 lt,-7.8 lt; f (G2) X / f (G1-G4) Xlt; -4.6); -4.1 lt;-4.1 lt; f (G3) X / f (G1-G4) Xlt; -0.9;-0.9; -1.5 lt,-1.5 lt; f (G6) Y / f (G5-G8) Ylt; 1.6); -1.3 lt; f (G1-G4) X / f (G5-G8) Xlt; 1.8); -1.6 lt,-1.6 lt; f (G1-G4) Y / f (G5-G8) Ylt; and 1.6. The lens has the optical properties of small size, large aperture, high resolution, low respiration, low distortion, high deformation ratio and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of optical lenses, and particularly to an anamorphic lens. Background Art

[0002] With the rapid development of Internet technology, taking photos and videos has become an essential part of the lives of ordinary consumers. In recent years, driven by technologies such as 5G, video sharing such as Vlogs has become more and more popular, and the number of people using tools such as mobile phones and cameras to shoot short films and micro-movies is increasing.

[0003] However, currently, the conventional shooting ratio of devices such as mobile phones, tablets, and cameras on the market is 16:9, while the ratio of wide-screen videos with a cinematic feel is 2.4:1. At the same time, good micro-movie or video shooting requires the cooperation of different focal length lenses. In particular, a medium and long focal length anamorphic lens is needed for close-ups of people.

[0004] Existing anamorphic lenses have technical problems such as high price, large volume and weight, large breathing effect, and non-constant magnification. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the technical problems of high price, large volume and weight, large breathing effect, and non-constant magnification existing in anamorphic lenses in the prior art, so as to provide an anamorphic lens.

[0006] To solve the above technical problems, the technical solution of the present invention is as follows: An anamorphic lens, comprising a first spherical lens group, a second spherical lens group, a first cylindrical lens group, a third spherical lens group, a fourth spherical lens group, a second cylindrical lens group, a fifth spherical lens group, and an aspherical lens group, which are sequentially arranged along the optical path from the object side to the image side; The first spherical lens group has a negative optical power, the second spherical lens group has a negative optical power, the first cylindrical lens group has a negative optical power, the third spherical lens group has a positive optical power, the fourth spherical lens group has a negative optical power, the second cylindrical lens group has a negative optical power, and the fifth spherical lens group has a positive optical power; The combined optical focal lengths of all lens groups satisfy the following conditional expressions: 1.3 < f(G1-G8)Y / f(G1-G8)X < 1.8; -7.8 < f(G2)X / f(G1-G4)X < -4.6; -4.1 < f(G3)X / f(G1-G4)X < -0.9; -1.5 < f(G6)Y / f(G5-G8)Y < 1.6; -1.3 < f(G1-G4)X / f(G5-G8)X < 1.8; -1.6 < f(G1 - G4)Y / f(G5 - G8)Y < 1.6; Wherein, the curvature direction of the first cylindrical lens group is the X direction, and the Y direction is the direction perpendicular to the X direction; f(Gm)X is the comprehensive optical focal length of the m-th lens group in the X direction, f(Gm)Y is the comprehensive optical focal length of the m-th lens group in the Y direction, f(Gm - Gn)X is the comprehensive optical focal length from the m-th lens group to the n-th lens group in the X direction, f(Gm - Gn)Y is the comprehensive optical focal length from the m-th lens group to the n-th lens group in the Y direction, m and n are both positive integers, and 1 ≤ m < n ≤ 8.

[0007] Furthermore, the first spherical lens group includes a first lens sequentially arranged along the optical path from the object side to the image side, and the first lens is a spherical lens with negative optical power; The second spherical lens group includes a second lens and a third lens sequentially arranged along the optical path from the object side to the image side, the second lens is a spherical lens with negative optical power, and the third lens is a spherical lens with positive optical power; The first cylindrical lens group includes a fourth lens, a fifth lens, and a sixth lens sequentially arranged along the optical path from the object side to the image side, the fourth lens and the fifth lens are both cylindrical lenses with negative optical power, and the sixth lens is a cylindrical lens with positive optical power; The third spherical lens group includes a seventh lens, an eighth lens, a ninth lens, a tenth lens, and an eleventh lens sequentially arranged along the optical path from the object side to the image side, the seventh lens is a spherical lens with negative optical power, the eighth lens is a spherical lens with positive optical power, the ninth lens is a spherical lens with positive optical power, the tenth lens is a spherical lens with positive optical power, and the eleventh lens is a spherical lens with negative optical power; The fourth spherical lens group includes a twelfth lens, and the twelfth lens is a spherical lens with negative optical power; The second cylindrical lens group includes a thirteenth lens, and the thirteenth lens is a cylindrical lens with negative optical power; The fifth spherical lens group includes a fourteenth lens, a fifteenth lens, a sixteenth lens, a seventeenth lens, and an eighteenth lens sequentially arranged along the optical path from the object side to the image side, the fourteenth lens is a spherical lens with positive optical power, the fifteenth lens is a spherical lens with negative optical power, the sixteenth lens is a spherical lens with negative optical power, the seventeenth lens is a spherical lens with positive optical power, and the eighteenth lens is a spherical lens with positive optical power; The aspherical lens group includes a nineteenth lens, and the nineteenth lens is an aspherical lens.

[0008] Furthermore, the second lens and the third lens form an internal focusing group.

[0009] Further, the fifth lens and the sixth lens are cemented to form a cemented cylindrical lens.

[0010] Further, the seventh lens and the eighth lens are cemented to form a cemented spherical lens; and / or, the tenth lens and the eleventh lens are cemented to form a cemented spherical lens; and / or, the fourteenth lens and the fifteenth lens are cemented to form a cemented spherical lens; and / or, the seventeenth lens and the eighteenth lens are cemented to form a cemented spherical lens.

[0011] Further, the focal length of the anamorphic lens in the Y direction is 44 mm.

[0012] Further, the zoom ratio of the anamorphic lens is 1.5X, and the magnification at different object distances remains constant.

[0013] Further, the overall optical length of the anamorphic lens does not exceed 180 mm.

[0014] Further, the F-number of the aperture of the anamorphic lens does not exceed 2.

[0015] Further, the lenses in the first spherical lens group, the second spherical lens group, the first cylindrical lens group, the third spherical lens group, the fourth spherical lens group, the second cylindrical lens group, and the fifth spherical lens group are all optical glass lenses; the lenses in the aspherical lens group are aspherical glass lenses.

[0016] The technical solution of the present invention has the following advantages: By combining and using the cylindrical lens group and the spherical lens group in the X direction, the optical power is reasonably distributed, making the optical structure of the anamorphic lens more compact and small, with lower cost. After the spherical lens group corrects the light rays comprehensively, and then using the optical characteristics of the cylindrical lens group, the light rays entering horizontally are "compressed", while the light rays entering vertically remain unchanged, thereby increasing the horizontal field of view of the lens shooting and ensuring the performance in the X direction. Then, the cylindrical lens group and the spherical lens group in the Y direction are used to stabilize the performance in the other direction. In this way, the full-frame and large magnification of the lens are realized. In addition, the integrated and compact design of the cylindrical lens and the spherical lens makes the lens small in volume, light in weight, and greatly reduces the cost. The aspherical lens can effectively correct the spherical aberration and astigmatism of the lens, improving the resolution of the lens while reducing the volume and weight of the lens. Description of the Drawings

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is the optical structure diagram of the anamorphic lens in the X direction when the object-image distance is infinite in the embodiment of the present invention; Figure 2 It is the optical structure diagram of the anamorphic lens in the Y direction when the object-image distance is infinite in the embodiment of the present invention; Figure 3 It is the spherical aberration, field curvature, and distortion diagram of the anamorphic lens when the object-image distance is infinite in the embodiment of the present invention; Figure 4 It is the optical structure diagram of the anamorphic lens in the X direction when the object-image distance is 0.65m in the embodiment of the present invention; Figure 5 It is the optical structure diagram of the anamorphic lens in the Y direction when the object-image distance is 0.65m in the embodiment of the present invention; Figure 6 It is the spherical aberration, field curvature, and distortion diagram of the anamorphic lens when the object-image distance is 0.65m in the embodiment of the present invention.

[0019] Explanation of reference numerals: G1, the first spherical lens group; G2, the second spherical lens group; G3, the first cylindrical lens group; G4, the third spherical lens group; G5, the fourth spherical lens group; G6, the second cylindrical lens group; G7, the fifth spherical lens group; G8, the aspherical lens group; 1, the first lens; 2, the second lens; 3, the third lens; 4, the fourth lens; 5, the fifth lens; 6, the sixth lens; 7, the seventh lens; 8, the eighth lens; 9, the ninth lens; 10, the tenth lens; 11, the eleventh lens; 12, the twelfth lens; 13, the thirteenth lens; 14, the fourteenth lens; 15, the fifteenth lens; 16, the sixteenth lens; 17, the seventeenth lens; 18, the eighteenth lens; 19, the nineteenth lens. Detailed embodiments

[0020] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the drawings. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0021] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0022] As Figures 1-6 shown, a deformable lens includes a first spherical lens group G1, a second spherical lens group G2, a first cylindrical lens group G3, a third spherical lens group G4, a fourth spherical lens group G5, a second cylindrical lens group G6, a fifth spherical lens group G7, and an aspherical lens group G8, which are sequentially arranged along the optical path from the object side to the image side. Among them, the first spherical lens group G1 has a negative optical power, the second spherical lens group G2 has a negative optical power, the first cylindrical lens group G3 has a negative optical power, the third spherical lens group G4 has a positive optical power, the fourth spherical lens group G5 has a negative optical power, the second cylindrical lens group G6 has a negative optical power, and the fifth spherical lens group G7 has a positive optical power; the lens of the aspherical lens group G8 is an aspherical glass lens.

[0023] The combined optical focal length of all lens groups satisfies the following conditional expressions: 1.3 < f(G1 - G8)Y / f(G1 - G8)X < 1.8; -7.8 < f(G2)X / f(G1 - G4)X < -4.6; -4.1 < f(G3)X / f(G1 - G4)X < -0.9; -1.5 < f(G6)Y / f(G5 - G8)Y < 1.6; -1.3 < f(G1 - G4)X / f(G5 - G8)X < 1.8; -1.6 < f(G1 - G4)Y / f(G5 - G8)Y < 1.6; Among them, the curvature direction of the first cylindrical lens group G3 is the X direction, and the Y direction is perpendicular to the X direction; f(G1-G8)Y is the combined optical focal length of the first spherical lens group G1 to the aspherical lens group G8 in the Y direction, f(G1-G8)X is the combined optical focal length of the first spherical lens group G1 to the aspherical lens group G8 in the X direction, f(G2)X is the combined optical focal length of the second spherical lens group G2 in the X direction, f(G3)X is the combined optical focal length of the first cylindrical lens group G3 in the X direction, f(G1-G4)X is the combined optical focal length of the first spherical lens group G1 to the third spherical lens group G4 in the X direction, f(G6)Y is the combined optical focal length of the second cylindrical lens group G6 in the Y direction, f(G5-G8)Y is the combined optical focal length of the fourth spherical lens group G5 to the aspherical lens group G8 in the Y direction, f(G5-G8)X is the combined optical focal length of the fourth spherical lens group G5 to the aspherical lens group G8 in the X direction, and f(G1-G4)Y is the combined optical focal length of the first spherical lens group G1 to the third spherical lens group G4 in the Y direction.

[0024] This anamorphic lens combines a cylindrical lens group in the X direction and a spherical lens group for use, rationally distributes the optical power, makes the optical structure of the anamorphic lens more compact and small, and has a lower cost. The spherical lens group comprehensively corrects the light rays, and then utilizes the optical characteristics of the cylindrical lens group to "compress" the light rays entering horizontally, while the light rays entering vertically remain unchanged, thereby increasing the horizontal field of view angle of the lens and ensuring the performance in the X direction. Then, the cylindrical lens group and the spherical lens group in the Y direction are used to stabilize the performance in the other direction. In this way, the full-frame and large magnification of the lens are achieved. In addition, the compact design of the integration of the cylindrical lens and the spherical lens makes the lens small in size, light in weight, and greatly reduces the cost. The aspherical lens can effectively correct the spherical aberration and astigmatism of the lens, improve the resolution of the lens while reducing the volume and weight of the lens.

[0025] In some embodiments of this embodiment, the first spherical lens group G1 includes a first lens 1 arranged in sequence from the object side to the image side along the optical path, and the first lens 1 is a spherical lens with negative optical power.

[0026] The second spherical lens group G2 includes a second lens 2 and a third lens 3 arranged in sequence from the object side to the image side along the optical path. The second lens 2 is a spherical lens with negative optical power, and the third lens 3 is a spherical lens with positive optical power.

[0027] The first cylindrical lens group G3 includes a fourth lens 4, a fifth lens 5, and a sixth lens 6 arranged in sequence from the object side to the image side along the optical path. Both the fourth lens 4 and the fifth lens 5 are cylindrical lenses with negative optical power, and the sixth lens 6 is a cylindrical lens with positive optical power.

[0028] The third spherical lens group G4 includes a seventh lens 7, an eighth lens 8, a ninth lens 9, a tenth lens 10, and an eleventh lens 11 arranged in sequence from the object side to the image side along the optical path. The seventh lens 7 is a spherical lens with negative optical power, the eighth lens 8 is a spherical lens with positive optical power, the ninth lens 9 is a spherical lens with positive optical power, the tenth lens 10 is a spherical lens with positive optical power, and the eleventh lens 11 is a spherical lens with negative optical power.

[0029] The fourth spherical lens group G5 includes a twelfth lens 12, and the twelfth lens 12 is a spherical lens with negative optical power.

[0030] The second cylindrical lens group G6 includes a thirteenth lens 13, and the thirteenth lens 13 is a cylindrical lens with negative optical power.

[0031] The fifth spherical lens group G7 includes a fourteenth lens 14, a fifteenth lens 15, a sixteenth lens 16, a seventeenth lens 17, and an eighteenth lens 18 arranged in sequence from the object side to the image side along the optical path. The fourteenth lens 14 is a spherical lens with positive optical power, the fifteenth lens 15 is a spherical lens with negative optical power, the sixteenth lens 16 is a spherical lens with negative optical power, the seventeenth lens 17 is a spherical lens with positive optical power, and the eighteenth lens 18 is a spherical lens with positive optical power.

[0032] The aspherical lens group G8 includes a nineteenth lens 19, and the nineteenth lens 19 is an aspherical lens.

[0033] The focal length distribution of the first lens 1 to the nineteenth lens 19 satisfies the following relationship: 1.3 < f(1 - 19)Y / f(1 - 19)X < 1.8; -7.8 < f(2 - 3)X / f(1 - 11)X < -4.6; -4.1 < f(4 - 6)X / f(1 - 11)X < -0.9; -1.5 < f(13)Y / f(12 - 19)Y < 1.6; -1.3 < f(1 - 11)X / f(12 - 19)X < 1.8; -1.6 < f(1 - 11)Y / f(12 - 19)Y < 1.6; Among them, the curvature direction of the sixth lens 6 is the X direction, and the Y direction is the direction perpendicular to the X direction; f(m - n)Y is the combined optical focal length of the mth lens to the nth lens along the Y direction, f(m - n)X is the combined optical focal length of the mth lens to the nth lens along the X direction, m and n are both positive integers, and 1 ≤ m < n ≤ 19. In some embodiments of this embodiment, the focal length distribution of the first lens 1 to the nineteenth lens 19 satisfies the following conditions: f(1 - 19)Y / f(1 - 19)X = 1.5; f(2 - 3)X / f(1 - 11)X = -6.2; -f(4 - 6)X / f(1 - 11)X = -2.6; f(13)Y / f(12 - 19)Y = 0.03; f(1 - 11)X / f(12 - 19)X = 0.22; f(1 - 11)Y / f(12 - 19)Y = -0.01.

[0034] In some embodiments of the present embodiment, the number of lenses in the anamorphic lens is not limited to 19 lenses, and the number of lenses in the anamorphic lens can be further changed as long as the combined optical focal lengths of various lens groups in the anamorphic lens satisfy the above mathematical relationship.

[0035] In the present embodiment, the combined optical focal length of the anamorphic lens in the Y direction is 44 mm. The zoom ratio of the anamorphic lens is 1.5X, and the magnification at different object distances remains constant. The overall optical length of the anamorphic lens does not exceed 180 mm. The F value of the aperture of the anamorphic lens does not exceed 2.

[0036] In the present embodiment, the second lens 2 and the third lens 3 form an internal focusing group. During adjustment, the overall length of the lens remains unchanged, and a floating internal focusing group is used to achieve focusing from 0.65 m to infinity for the object image distance, while overcoming the technical difficulties of large breathing effect and non-constant magnification of the 44 mm anamorphic lens.

[0037] In the present embodiment, the fifth lens 5 and the sixth lens 6 are cemented to form a doublet cylindrical lens; the seventh lens 7 and the eighth lens 8 are cemented to form a doublet spherical lens; the tenth lens 10 and the eleventh lens 11 are cemented to form a doublet spherical lens; the fourteenth lens 14 and the fifteenth lens 15 are cemented to form a doublet spherical lens; the seventeenth lens 17 and the eighteenth lens 18 are cemented to form a doublet spherical lens. The doublet spherical lenses are used to correct the optical chromatic aberration of the anamorphic lens in the horizontal and vertical directions.

[0038] It should be noted that the above combination method of multiple doublet spherical lenses is bonding. As an alternative embodiment, based on the concept of the present invention, in order to distinguish it from the present application, after changing the above combination method, such as bonding, integrally forming, etc., and then making an adaptive change to the shape of the combined lens, it should also be included in the protection scope of the present application. For a single lens or two consecutive lenses with the same sign of optical power, the single lens can be split into two or more lenses, or two consecutive lenses with the same sign can be combined into one lens. Such simple transformations of the optical structure of the patent, such as the optical power distribution of the transformed lens or lens group within the range of the mathematical relationship expression of the patent. On the basis of the present embodiment, changes and replacements made to the number of lenses and the combination method in order to distinguish it from the present application, without departing from the main idea of the present application, all belong to the protection scope of the present application.

[0039] In this embodiment, the lenses in the first spherical lens group G1, the second spherical lens group G2, the first cylindrical lens group G3, the third spherical lens group G4, the fourth spherical lens group G5, the second cylindrical lens group G6, and the fifth spherical lens group G7 are all optical glass lenses, and the lenses in the aspherical lens group G8 are aspherical glass lenses.

[0040] See Figure 3 As shown, they are the spherical aberration diagram, the field curvature diagram, and the distortion diagram of the anamorphic lens. It can be seen from the curves in the figure that the spherical aberration is basically less than ±0.5, ensuring the clarity of the image center; the field curvature is basically less than ±0.5, ensuring the same clarity for the large field of view; the distortion is less than 10%, ensuring a small amount of deformation in the imaging picture.

[0041] Refer to Figure 4 and Figure 5 , adjust the internal focusing group within the anamorphic lens, and the overall length of the anamorphic lens remains unchanged, realizing an ultra-close object image distance of 0.65 m for the large magnification anamorphic lens in the full frame.

[0042] See Figure 6 As shown, they are the spherical aberration diagram, the field curvature diagram, and the distortion diagram of the anamorphic lens at a short object distance. It can be seen from the curves in the figure that the spherical aberration is basically less than ±0.5, ensuring the clarity of the image center; each field curvature is basically less than ±0.5, ensuring the same clarity for the large field of view; the distortion is less than 10%, ensuring a small amount of deformation in the imaging picture.

[0043] The following Table 1 lists the actual parameters of each lens in this embodiment that meet the above mathematical relationship: Table 1

[0044] The following Table 2 shows the aspherical coefficients of the nineteenth lens 19: Table 2

[0045] The anamorphic lens provided by the present invention adopts an integrated design, achieving excellent ultra-cost-effective optical performance such as a small lens volume, high resolution, low breathing, low distortion, full frame, and 1.5X high magnification. It can be designed to be compatible with the mounts of various brands of cameras according to actual usage requirements to achieve personalized customization and general compatibility.

[0046] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A variable-focus lens, characterized in that, It includes a first spherical lens group (G1), a second spherical lens group (G2), a first cylindrical lens group (G3), a third spherical lens group (G4), a fourth spherical lens group (G5), a second cylindrical lens group (G6), a fifth spherical lens group (G7) and an aspherical lens group (G8) which are sequentially arranged from the object side to the image side along the optical path; the first spherical lens group (G1), the second spherical lens group (G2), the first cylindrical lens group (G3), the fourth spherical lens group (G5), and the second cylindrical lens group (G6) all have negative optical powers, and the third spherical lens group (G4) and the fifth spherical lens group (G7) both have positive optical powers; The combined optical focal lengths of all lens groups satisfy the following conditional expressions: 1.3 < f(G1 - G8)Y / f(G1 - G8)X < 1.8; -7.8 < f(G2)X / f(G1 - G4)X < -4.6; -4.1 < f(G3)X / f(G1 - G4)X < -0.9; -1.5 < f(G6)Y / f(G5 - G8)Y < 1.6; -1.3 < f(G1 - G4)X / f(G5 - G8)X < 1.8; -1.6 < f(G1 - G4)Y / f(G5 - G8)Y < 1.6; Wherein, the curvature direction of the first cylindrical lens group (G3) is the X direction, and the Y direction is the direction perpendicular to X; f(Gm)X is the combined optical focal length of the mth lens group along the X direction, f(Gm)Y is the combined optical focal length of the mth lens group along the Y direction, f(Gm - Gn)X is the combined optical focal length of the mth lens group to the nth lens group along the X direction, f(Gm - Gn)Y is the combined optical focal length of the mth lens group to the nth lens group along the Y direction, m and n are both positive integers, and 1 ≤ m < n ≤ 8.

2. The deformable lens according to claim 1, wherein, The first spherical lens group (G1) includes a first lens (1), and the first lens (1) is a spherical lens with negative optical power; The second spherical lens group (G2) includes a second lens (2) and a third lens (3) which are sequentially arranged from the object side to the image side along the optical path. The second lens (2) is a spherical lens with negative optical power, and the third lens (3) is a spherical lens with positive optical power; The first cylindrical lens group (G3) includes a fourth lens (4), a fifth lens (5) and a sixth lens (6) which are sequentially arranged from the object side to the image side along the optical path. The fourth lens (4) and the fifth lens (5) are both cylindrical lenses with negative optical power, and the sixth lens (6) is a cylindrical lens with positive optical power; The third spherical lens group (G4) includes a seventh lens (7), an eighth lens (8), a ninth lens (9), a tenth lens (10) and an eleventh lens (11) which are sequentially arranged from the object side to the image side along the optical path. The seventh lens (7) and the eleventh lens (11) are both spherical lenses with negative optical power, and the eighth lens (8), the ninth lens (9) and the tenth lens (10) are all spherical lenses with positive optical power; The fourth spherical lens group (G5) includes a twelfth lens (12), and the twelfth lens (12) is a spherical lens with negative optical power; The second cylindrical lens group (G6) includes a thirteenth lens (13), and the thirteenth lens (13) is a cylindrical lens with a negative optical power; The fifth spherical lens group (G7) includes a fourteenth lens (14), a fifteenth lens (15), a sixteenth lens (16), a seventeenth lens (17), and an eighteenth lens (18) arranged in sequence from the object side to the image side along the optical path. The fourteenth lens (14), the seventeenth lens (17), and the eighteenth lens (18) are all spherical lenses with positive optical powers, and the fifteenth lens (15) and the sixteenth lens (16) are both spherical lenses with negative optical powers; The aspherical lens group (G8) includes a nineteenth lens (19), and the nineteenth lens (19) is an aspherical lens.

3. The anamorphic lens according to claim 2, wherein, The second lens (2) and the third lens (3) form an internal focusing group.

4. The anamorphic lens according to claim 2, wherein, The fifth lens (5) and the sixth lens are cemented to form a cemented cylindrical lens.

5. The anamorphic lens according to claim 2, characterized in that, The seventh lens (7) and the eighth lens (8) are cemented to form a cemented spherical lens; and / or, the tenth lens (10) and the eleventh lens (11) are cemented to form a cemented spherical lens; and / or, the fourteenth lens (14) and the fifteenth lens (15) are cemented to form a cemented spherical lens; and / or, the seventeenth lens (17) and the eighteenth lens (18) are cemented to form a cemented spherical lens.

6. The anamorphic lens according to claim 1, characterized in that The integrated optical focal length of the anamorphic lens in the Y direction is 44 mm.

7. The anamorphic lens according to claim 1, characterized in that, The zoom ratio of the anamorphic lens is 1.5X, and the magnification at different object distances remains constant.

8. The anamorphic lens according to claim 1, wherein The overall optical length of the anamorphic lens does not exceed 180 mm.

9. The anamorphic lens according to claim 1, wherein The F-number of the aperture of the anamorphic lens does not exceed 2.

10. The anamorphic lens according to claim 1, characterized in that, The lenses in the first spherical lens group (G1), the second spherical lens group (G2), the first cylindrical lens group (G3), the third spherical lens group (G4), the fourth spherical lens group (G5), the second cylindrical lens group (G6), and the fifth spherical lens group (G7) are all optical glass lenses; the lens in the aspherical lens group (G8) is an aspherical glass lens.

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