A anamorphic lens

Abstract

The present invention discloses a deformable lens, belonging to the field of optical lenses, which includes 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 lens groups satisfy: 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. It has optical properties such as small lens volume, large aperture, high resolution, low breathing, low distortion, and high deformation ratio.

Description

Technical Field

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

[0002] With the rapid development of internet technology, taking photos and videos has become an essential part of everyday life for ordinary consumers. In recent years, driven by technologies like 5G, the sharing of videos like vlogs has become increasingly popular, and more and more people are using mobile phones, cameras, and other tools to shoot short videos and micro-films.

[0003] However, the typical shooting ratio on mobile phones, tablets, cameras, and other devices on the market is 16:9, while the ratio for cinematic widescreen videos is 2.4:1. Furthermore, shooting a good micro-film or video requires lenses of different focal lengths to work together, especially close-ups of characters, which require medium- to long-focus anamorphic lenses.

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

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the technical problems of the prior art anamorphic lenses, such as high price, large volume and weight, large breathing effect, and unstable magnification, thereby providing an anamorphic lens.

[0006] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0007] 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 arranged in sequence along an optical path from the object side to the image side;

[0008] The first spherical lens group has negative optical power, the second spherical lens group has negative optical power, the first cylindrical lens group has negative optical power, the third spherical lens group has positive optical power, the fourth spherical lens group has negative optical power, the second cylindrical lens group has negative optical power, and the fifth spherical lens group has positive optical power;

[0009] The comprehensive optical focal length of all lens groups satisfies the following condition:

[0010] 1.3 <f(G1-G8)Y / f(G1-G8)X<1.8;

[0011] -7.8 <f(G2)X / f(G1-G4)X<-4.6;

[0012] -4.1 <f(G3)X / f(G1-G4)X<-0.9;

[0013] -1.5 <f(G6)Y / f(G5-G8)Y<1.6;

[0014] -1.3 <f(G1-G4)X / f(G5-G8)X<1.8;

[0015] -1.6 <f(G1-G4)Y / f(G5-G8)Y<1.6;

[0016] 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 along the X direction, f(Gm)Y is the comprehensive optical focal length of the m-th lens group along 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 along the X direction, and f(Gm-Gn)Y is the comprehensive optical focal length from the m-th lens group to the n-th lens group along the Y direction, m and n are both positive integers, and 1≤m<n≤8.

[0017] Furthermore, the first spherical lens group includes first lenses sequentially arranged along the optical path from the object side to the image side, and the first lenses are spherical lenses with negative optical power;

[0018] The second spherical lens group includes a second lens and a third lens arranged in sequence 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;

[0019] The first cylindrical lens group includes a fourth lens, a fifth lens, and a sixth lens arranged in sequence 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;

[0020] The third spherical lens group includes a seventh lens, an eighth lens, a ninth lens, a tenth lens, and an eleventh lens, which are arranged in sequence along the optical path from the object side to the image side, wherein 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;

[0021] The fourth spherical lens group includes a twelfth lens, and the twelfth lens is a spherical lens with negative optical power;

[0022] The second cylindrical lens group includes a thirteenth lens, and the thirteenth lens is a cylindrical lens with negative optical power;

[0023] The fifth spherical lens group includes a fourteenth lens, a fifteenth lens, a sixteenth lens, a seventeenth lens, and an eighteenth lens arranged in sequence 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;

[0024] The aspheric lens group includes a nineteenth lens, and the nineteenth lens is an aspheric lens.

[0025] Furthermore, the second lens and the third lens constitute an inner focus group.

[0026] Furthermore, the fifth lens and the sixth lens are cemented together to form a double cemented cylindrical lens.

[0027] Furthermore, the seventh lens and the eighth lens are cemented to form a double cemented spherical lens; and / or, the tenth lens and the eleventh lens are cemented to form a double cemented spherical lens; and / or, the fourteenth lens and the fifteenth lens are cemented to form a double cemented spherical lens; and / or, the seventeenth lens and the eighteenth lens are cemented to form a double cemented spherical lens.

[0028] Furthermore, the focal length of the anamorphic lens in the Y direction is 44 mm.

[0029] Furthermore, the zoom ratio of the anamorphic lens is 1.5X, and the magnification ratio remains constant at different object distances.

[0030] Furthermore, the total optical length of the anamorphic lens does not exceed 180 mm.

[0031] Furthermore, the aperture F value of the anamorphic lens does not exceed 2.

[0032] Furthermore, 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; and the lenses in the aspherical lens group are aspherical glass lenses.

[0033] The technical solution of the present invention has the following advantages: by combining an X-direction cylindrical lens group and a spherical lens group, the optical power is rationally distributed, making the optical structure of the anamorphic lens more compact and cost-effective. The spherical lens group comprehensively corrects the light, and then utilizes the optical properties of the cylindrical lens group to "compress" the light entering horizontally while keeping the light entering vertically unchanged, thereby increasing the lens's horizontal field of view and ensuring performance in the X direction. The Y-direction cylindrical lens group and spherical lens group then stabilize performance in the other direction. In this way, the full frame and high magnification of the lens are achieved. In addition, the compact design of the integrated cylindrical and spherical lenses makes the lens small and lightweight, greatly reducing cost. The aspherical lens can effectively correct the lens's spherical aberration and astigmatism, improving the lens's resolution while reducing its size and weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] Figure 1 This is an optical structure diagram of the anamorphic lens in the X direction when the object-image distance is infinite in an embodiment of the present invention;

[0036] Figure 2 This is an optical structure diagram of the anamorphic lens in the Y direction when the object-image distance is infinite in an embodiment of the present invention;

[0037] Figure 3 Graphs showing spherical aberration, field curvature, and distortion of an anamorphic lens when the object-image distance is infinite in an embodiment of the present invention;

[0038] Figure 4 : This is an optical structure diagram of the anamorphic lens in the X direction when the object-image distance is 0.65m in an embodiment of the present invention;

[0039] Figure 5 : This is an optical structure diagram of the anamorphic lens in the Y direction when the object-image distance is 0.65m in an embodiment of the present invention;

[0040] Figure 6 Graphs showing spherical aberration, field curvature, and distortion of the anamorphic lens when the object-image distance is 0.65 m in an embodiment of the present invention.

[0041] Explanation of the accompanying drawings: G1, first spherical lens group; G2, second spherical lens group; G3, first cylindrical lens group; G4, third spherical lens group; G5, fourth spherical lens group; G6, second cylindrical lens group; G7, fifth spherical lens group; G8, aspherical lens group; 1, first lens; 2, second lens; 3, third lens; 4, fourth lens; 5, fifth lens; 6, sixth lens; 7, seventh lens; 8, eighth lens; 9, ninth lens; 10, tenth lens; 11, eleventh lens; 12, twelfth lens; 13, thirteenth lens; 14, fourteenth lens; 15, fifteenth lens; 16, sixteenth lens; 17, seventeenth lens; 18, eighteenth lens; 19, nineteenth lens. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0043] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] like Figures 1-6 The anamorphic lens shown 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 arranged in sequence along the optical path from the object side to the image side. The first spherical lens group G1 has negative optical power, the second spherical lens group G2 has negative optical power, the first cylindrical lens group G3 has negative optical power, the third spherical lens group G4 has positive optical power, the fourth spherical lens group G5 has negative optical power, the second cylindrical lens group G6 has negative optical power, and the fifth spherical lens group G7 has positive optical power. The lenses of the aspherical lens group G8 are aspherical glass lenses.

[0045] The comprehensive optical focal length of all lens groups satisfies the following condition:

[0046] 1.3 <f(G1-G8)Y / f(G1-G8)X<1.8;

[0047] -7.8 <f(G2)X / f(G1-G4)X<-4.6;

[0048] -4.1 <f(G3)X / f(G1-G4)X<-0.9;

[0049] -1.5 <f(G6)Y / f(G5-G8)Y<1.6;

[0050] -1.3 <f(G1-G4)X / f(G5-G8)X<1.8;

[0051] -1.6 <f(G1-G4)Y / f(G5-G8)Y<1.6;

[0052] 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(G1-G8)Y is the comprehensive optical focal length of the first spherical lens group G1 to the aspherical lens group G8 along the Y direction, f(G1-G8)X is the comprehensive optical focal length of the first spherical lens group G1 to the aspherical lens group G8 along the X direction, f(G2)X is the comprehensive optical focal length of the second spherical lens group G2 along the X direction, f(G3)X is the comprehensive optical focal length of the first cylindrical lens group G3 along the X direction, and f(G1-G4)X is the comprehensive optical focal length of the first cylindrical lens group G3 along the X direction. is the combined optical focal length of the first spherical lens group G1 to the third spherical lens group G4 along the X direction, f(G6)Y is the combined optical focal length of the second cylindrical lens group G6 along 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 along 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 along 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 along the Y direction.

[0053] This anamorphic lens combines an X-direction cylindrical lens group with a spherical lens group to rationally distribute optical power, making the anamorphic lens's optical structure more compact and cost-effective. The spherical lens group provides comprehensive correction for light, and then leverages the optical properties of the cylindrical lens group to "compress" horizontally entering light while maintaining vertical light. This increases the lens' horizontal field of view and ensures performance in the X direction. The Y-direction cylindrical and spherical lens groups stabilize performance in the other direction. This enables the lens's full frame and high magnification. Furthermore, the compact, integrated design of the cylindrical and spherical lenses results in a small, lightweight lens, significantly reducing cost. The aspherical lens effectively corrects spherical aberration and astigmatism, improving resolution while reducing size and weight.

[0054] In some implementations of this embodiment, the first spherical lens group G1 includes first lenses 1 sequentially arranged along the optical path from the object side to the image side, and the first lenses 1 are spherical lenses with negative optical power.

[0055] The second spherical lens group G2 includes a second lens 2 and a third lens 3 arranged in sequence along the optical path from the object side to the image side. 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.

[0056] The first cylindrical lens group G3 includes a fourth lens 4, a fifth lens 5 and a sixth lens 6 arranged in sequence along the optical path from the object side to the image side. 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.

[0057] 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 arranged in sequence along the optical path from the object side to the image side. 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 are all spherical lenses with negative optical power.

[0058] The fourth spherical lens group G5 includes a twelfth lens 12 , which is a spherical lens with negative optical power.

[0059] The second cylindrical lens group G6 includes a thirteenth lens 13 , which is a cylindrical lens with negative refractive power.

[0060] 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, which are arranged in sequence along the optical path from the object side to the image side. 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.

[0061] The aspherical lens group G8 includes a nineteenth lens 19 , which is an aspherical lens.

[0062] 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;

[0063] -7.8 <f(2-3)X / f(1-11)X<-4.6;

[0064] -4.1 <f(4-6)X / f(1-11)X<-0.9;

[0065] -1.5 <f(13)Y / f(12-19)Y<1.6;

[0066] -1.3 <f(1-11)X / f(12-19)X<1.8;

[0067] -1.6 <f(1-11)Y / f(12-19)Y<1.6;

[0068] The curvature direction of the sixth lens 6 is the X direction, and the Y direction is perpendicular to the X direction; f(mn)Y is the combined optical focal length of the m-th lens to the n-th lens along the Y direction, and f(mn)X is the combined optical focal length of the m-th lens to the n-th lens along the X direction, where m and n are both positive integers, and 1≤m<n≤19. In some implementations of this embodiment, the focal length distribution of the first lens 1 to the nineteenth lens 19 satisfies the following condition: f(1-19)Y / f(1-19)X=1.5;

[0069] f(2-3)X / f(1-11)X=-6.2;

[0070] -f(4-6)X / f(1-11)X=-2.6;

[0071] f(13)Y / f(12-19)Y=0.03;

[0072] f(1-11)X / f(12-19)X=0.22;

[0073] f(1-11)Y / f(12-19)Y=-0.01.

[0074] In some implementations of this embodiment, the number of lenses in the anamorphic lens is not limited to 19 lenses. The number of lenses in the anamorphic lens can be further varied as long as the combined optical focal lengths of the various lens groups in the anamorphic lens satisfy the above mathematical relationship.

[0075] In this embodiment, the anamorphic lens has a comprehensive optical focal length in the Y direction of 44 mm. The zoom ratio of the anamorphic lens is 1.5X, and the magnification ratio remains constant at different object distances. The total optical length of the anamorphic lens does not exceed 180 mm. The aperture value of the anamorphic lens does not exceed 2.

[0076] In this embodiment, the second lens element 2 and the third lens element 3 form an inner focusing group. While the overall length of the lens remains constant during adjustment, the floating inner focusing group enables focus from an object-image distance of 0.65m to infinity, while overcoming the technical difficulties of the large breathing effect and variable magnification of a 44mm anamorphic lens.

[0077] In this embodiment, the fifth lens 5 and the sixth lens 6 are cemented to form a double cemented cylindrical lens; the seventh lens 7 and the eighth lens 8 are cemented to form a double cemented spherical lens; the tenth lens 10 and the eleventh lens 11 are cemented to form a double cemented spherical lens; the fourteenth lens 14 and the fifteenth lens 15 are cemented to form a double cemented spherical lens; and the seventeenth lens 17 and the eighteenth lens 18 are cemented to form a double cemented spherical lens. The double cemented spherical lens is used to correct the optical chromatic aberration of the anamorphic lens in the horizontal and vertical directions.

[0078] It should be pointed out that the above-mentioned multiple groups of double-glued spherical lenses are combined by bonding. As an alternative embodiment, based on the concept of the present invention, in order to distinguish it from the present application, after the above-mentioned combination method is changed, such as bonding, integral molding and other combination methods, and then the shape of the combined lens is adaptively changed, it should also be included in the protection scope of the present application. For a single lens or two consecutive lenses with the same optical power, a single lens can be split into two or more lenses, and 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 distribution of the optical power of the transformed lens or lens group, are within the scope of the mathematical relationship expression of the patent. On the basis of this embodiment, changes and replacements of the number and combination of lenses in order to distinguish it from the present application, without departing from the main idea of ​​the present application, all fall within the protection scope of the present application.

[0079] 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.

[0080] See also Figure 3 As shown in the figure, the spherical aberration, field curvature and distortion diagrams of the anamorphic lens are as follows. 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 that the image has the same clarity in a large field of view; the distortion is less than 10%, ensuring that the imaging image has a small deformation.

[0081] Reference Figure 4 and Figure 5 By adjusting the internal focus group in the anamorphic lens, the overall length of the anamorphic lens remains unchanged, achieving an ultra-close object-to-image distance of 0.65m for a medium to large magnification anamorphic lens in full-frame.

[0082] See also Figure 6As shown in the figure, the spherical aberration, field curvature and distortion diagrams of the anamorphic lens at close object distance are as follows. 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 curvatures are basically less than ±0.5, ensuring the same clarity of the large field of view; the distortion is less than 10%, ensuring that the imaging screen has a small deformation.

[0083] Table 1 below lists the actual parameters of each lens of this embodiment that conform to the above mathematical relationship:

[0084] Table 1

[0085]

[0086] The following Table 2 shows the aspheric coefficients of the nineteenth lens 19:

[0087] Table 2

[0088]

[0089] The anamorphic lens provided by this invention adopts an integrated design, achieving a compact lens size while also achieving excellent cost-effective optical performance such as high resolution, low breathing, low distortion, full frame, and a high magnification of 1.5X. It can be designed to be compatible with the mounts of various camera brands on the market according to actual usage requirements, enabling personalized customization and universal compatibility.

[0090] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. An anamorphic lens, characterized in that: The optical lens comprises 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 arranged in sequence along an optical path from the object side to the image side; 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 power, and the third spherical lens group (G4) and the fifth spherical lens group (G7) both have positive optical power; The comprehensive optical focal length of all lens groups satisfies the following condition: 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; The curvature direction of the first cylindrical lens group (G3) 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 along the X direction, f(Gm)Y is the comprehensive optical focal length of the m-th lens group along 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 along the X direction, and f(Gm-Gn)Y is the comprehensive optical focal length from the m-th lens group to the n-th lens group along the Y direction, m and n are both positive integers, and 1≤m<n≤8.

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

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

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

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

6. The anamorphic lens according to claim 1, wherein: The comprehensive optical focal length of the anamorphic lens in the Y direction is 44 mm.

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

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

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

10. The anamorphic lens according to claim 1, wherein: 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 lenses in the aspherical lens group (G8) are aspherical glass lenses.

Images