A lens

Abstract

The present application relates to photographic equipment technical field, especially a lens, including in order along the light incident direction set front mirror group, diaphragm and rear mirror group, the front mirror group is fixed mirror group, the rear mirror group is the adjustment mirror group that can move along the light incident line, the diaphragm is connected with the front mirror group or the diaphragm is connected with the rear mirror group;The front mirror group includes four groups of lenses, and the rear mirror group includes four groups of lenses, each group of lenses includes at least one lens, the lens in the rear mirror group located at the end of the end away from the front mirror group is aspherical lens;The resolution and contrast of the lens obtained by the design are better, and the field curvature is small;Meanwhile, the diaphragm of the application can be connected with the front mirror group or the rear mirror group, which is beneficial to the structural diversity of the lens.

Description

[Technical Field] This invention relates to the field of photographic equipment technology, and in particular to a lens. [Background Technology] With the advancement of smart technology, electronic products such as computers, mobile phones, and camera modules have become essential tools for modern people. Camera modules, in particular, meet users' needs to record life's moments anytime, anywhere, making them one of the most popular electronic products. People's requirements for camera lenses are gradually increasing, but the existing lens types are too limited. [Summary of the Invention] To address the problem of the limited variety of existing lenses, this invention provides a novel lens.

[0001] The solution to the technical problem of the present invention is to provide a lens, including a front lens group, an aperture stop and a rear lens group arranged sequentially along the incident direction of light. The front lens group is a fixed lens group, the rear lens group is an adjustable lens group that can move along the incident line of light, and the aperture stop is connected to the front lens group or the aperture stop is connected to the rear lens group. The front lens group includes four lens groups, and the rear lens group includes four lens groups. Each lens group includes at least one lens. The lens in the rear lens group located at the end furthest from the front lens group is an aspherical lens.

[0002] Preferably, the front lens group includes a first lens group, a second lens group, a third lens group, and a fourth lens group arranged sequentially along the incident direction of light. The first lens group includes a first lens, the second lens group includes a second lens and a third lens that are closely attached to each other, the third lens group includes a fourth lens and a fifth lens that are closely attached to each other, and the fourth lens group includes a sixth lens and a seventh lens that are closely attached to each other.

[0003] Preferably, the rear lens group includes a fifth lens group, a sixth lens group, a seventh lens group, and an eighth lens group arranged sequentially along the incident direction of light. The fifth lens group includes an eighth lens and a ninth lens that are closely attached to each other. The sixth lens group includes a tenth lens. The seventh lens group includes an eleventh lens and a twelfth lens that are closely attached to each other. The eighth lens group includes a thirteenth lens, and the thirteenth lens is an aspherical lens.

[0004] Preferably, the second lens, the fifth lens, the sixth lens, the ninth lens, the tenth lens, and the eleventh lens are positive lenses, and the first lens, the third lens, the fourth lens, the seventh lens, the eighth lens, and the twelfth lens are negative lenses.

[0005] Preferably, the focal length of the rear lens group is less than the focal length of the front lens group.

[0006] Preferably, the aspherical lens includes a concave surface and a convex surface, and the convex surface of the aspherical lens satisfies the following formula: , Indicates the full diameter of the convex surface. The radius of the convex surface is represented by ; the concave surface of the aspherical lens satisfies the following formula: , Indicates the full diameter of the concave surface. Indicates the radius of the concave surface.

[0007] Preferably, the interval between the first lens group and the second lens group is 5.00~6.00mm; and / or, the interval between the second lens group and the third lens group is 16.00~17.00mm; and / or, the interval between the third lens group and the fourth lens group is 0~1.00mm; and / or, the interval between the fifth lens group and the sixth lens group is 0~1.00mm; and / or, the interval between the sixth lens group and the seventh lens group is 0~1.00mm; and / or, the interval between the seventh lens group and the eighth lens group is 1.00~2.00mm.

[0008] Preferably, the refractive index of the first lens is in the range of 1.55 to 1.62; and / or, the refractive index of the second lens is in the range of 1.45 to 1.55; and / or, the refractive index of the third lens is in the range of 1.65 to 1.75; and / or, the refractive index of the fourth lens is in the range of 1.65 to 1.75; and / or, the refractive index of the fifth lens is in the range of 1.85 to 1.95; and / or, the refractive index of the sixth lens is in the range of 1.85 to 1.95; and / or, the refractive index of the seventh lens is in the range of 1.85 to 1.95. The refractive index ranges as follows: 1.75 to 1.85; and / or, the refractive index range of the eighth lens is 1.70 to 1.80; and / or, the refractive index range of the ninth lens is 1.65 to 1.75; and / or, the refractive index range of the tenth lens is 1.95 to 2.05; and / or, the refractive index range of the eleventh lens is 1.65 to 1.75; and / or, the refractive index range of the twelfth lens is 1.75 to 1.85; and / or, the refractive index range of the thirteenth lens is 1.75 to 1.85.

[0009] Preferably, the Abbe number of the first lens is in the range of 59 to 61; and / or, the Abbe number of the second lens is in the range of 80 to 83; and / or, the Abbe number of the third lens is in the range of 28 to 31; and / or, the Abbe number of the fourth lens is in the range of 48 to 50; and / or, the Abbe number of the fifth lens is in the range of 38 to 40; and / or, the Abbe number of the sixth lens is in the range of 30 to 32; and / or, the Abbe number of the seventh lens is in the range of 59 to 61; and / or, the Abbe number of the fifth lens is in the range of 80 to 83; and / or, the Abbe number of the sixth lens is in the range of 30 to 32; and / or, the Abbe number of the seventh lens is in the range of 30 to 32. The Abbe number of the eighth lens is in the range of 24 to 26; and / or the Abbe number of the ninth lens is in the range of 48 to 50; and / or the Abbe number of the tenth lens is in the range of 24 to 26; and / or the Abbe number of the eleventh lens is in the range of 48 to 50; and / or the Abbe number of the twelfth lens is in the range of 24 to 26; and / or the Abbe number of the thirteenth lens is in the range of 40 to 42.

[0010] Preferably, the lens has a focal length of 16.9mm and an aperture of F0.90~F1.05.

[0011] Preferably, the lens has a focal length of 20mm and an aperture of F0.95; the second lens, the fifth lens, the sixth lens, the ninth lens, the tenth lens, and the eleventh lens are positive lenses convex to the object side, the first lens is a negative lens convex to the object side, the third lens, the fourth lens, the seventh lens, the eighth lens, and the twelfth lens are negative lenses concave to the object side, and the thirteenth lens is an aspherical lens convex to the object side.

[0012] Preferably, the lens further includes a housing assembly, the front lens group is connected to the housing assembly, the rear lens group is a focusing group, the aperture is connected to the rear lens group, and the aperture can move with the rear lens group.

[0013] Compared with the prior art, the lens of the present invention has the following advantages: 1. The lens of the present invention has a front lens group and a rear lens group, and four lens groups are respectively set in the front and rear lens groups. Then, the lens in the rear lens group located at the end far from the front lens group is set as an aspherical lens. The lens obtained by this design has better resolution and contrast and smaller field curvature. At the same time, the aperture of the present application can be connected to the front lens group or the rear lens group, which is conducive to enriching the structural diversity of the lens.

[0014] 2. This invention uses a lens structure consisting of eight groups of thirteen lenses to form the lens, thereby optimizing the lens structure. The front lens group consists of four groups of seven lenses, and the rear lens group consists of four groups of six lenses.

[0015] 3. The lens group of the present invention uses a variety of lenses, and optimizes the lens structure by combining positive lenses, negative lenses and aspherical lenses.

[0016] 4. By optimizing the spacing between lenses, the refractive index of the lens, and the Abbe number range, this invention enables the lens to achieve superior performance, with an aperture size between 0.8 and 1.1, a focal length of 16.9mm, and minimal lens distortion. At the optimal object distance, the MTF for 10 line pairs is greater than 0.9, and the MTF for 30 line pairs is greater than 0.75.

[0017] 5. This invention provides a lens with excellent performance, featuring a focal length of 20mm and an aperture of F0.95, through the careful design and combination of multiple lenses.

[0018] 6. In this invention, the lens also includes a housing assembly, the front lens group is connected to the housing assembly, the rear lens group is a focusing group, the aperture is connected to the rear lens group, and the aperture can move with the rear lens group; it can be understood that by making the aperture move synchronously with the rear lens group, the breathing effect during use can be effectively reduced, so that the lens can have an almost zero breathing effect when in use. [Attached Image Description] To more clearly illustrate the technical solutions in the embodiments of the present invention, 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 the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the lens arrangement in the lens provided in the first embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of another arrangement of lenses in the lens provided in the first embodiment of the present invention.

[0021] Figure 3 This is a lens parameter table provided in the first embodiment of the present invention.

[0022] Figure 4 This is an MTF (modulation transfer function) curve of the lens provided in the first embodiment of the present invention.

[0023] Figure 5 This is a field curvature and distortion curve diagram of the lens provided in the first embodiment of the present invention.

[0024] Explanation of reference numerals in the attached diagram: 1. Front lens assembly; 11. First lens group; 111. First lens; 12. Second lens group; 121. Second lens; 122. Third lens; 13. Third lens group; 131. Fourth lens; 132. Fifth lens; 14. Fourth lens group; 141. Sixth lens; 142. Seventh lens; 2. Rear mirror assembly; 21. Fifth lens group; 211. Eighth lens; 212. Ninth lens; 22. Sixth lens group; 221. Tenth lens; 23. Seventh lens group; 231. Eleventh lens; 232. Twelfth lens; 24. Eighth lens group; 241. Thirteenth lens; 3. Aperture; 41. Line 10 corresponds to the sagittal curve; 42. Line 10 corresponds to the meridian curve; 43. Line 30 corresponds to the sagittal curve; 44. Line 30 corresponds to the meridian curve.

Detailed Implementation Methods

[0025] The terms “vertical,” “horizontal,” “left,” “right,” “up,” “down,” “upper left,” “upper right,” “lower left,” “lower right,” “lower left,” “lower right,” and similar expressions used in this article are for illustrative purposes only.

[0026] Please combine Figure 1 and Figure 2 The first embodiment of the present invention provides a lens, including a front lens group 1, an aperture 3 and a rear lens group 2 arranged sequentially along the incident direction of light. The front lens group 1 is a fixed lens group, the rear lens group 2 is an adjustable lens group that can move along the incident line of light, and the aperture 3 is connected to the front lens group 1 or the aperture 3 is connected to the rear lens group 2. The front lens group 1 includes four lens groups, and the rear lens group 2 includes four lens groups. Each lens group includes at least one lens. The lens in the rear lens group 2 located at the end furthest from the front lens group 1 is an aspherical lens.

[0027] It is understood that the lens in the embodiment of the present invention sets up a front lens group 1 and a rear lens group 2, and sets four groups of lenses in the front and rear lens groups 2 respectively. Then, the lens in the rear lens group 2 located at the end far from the front lens group 1 is set as an aspherical lens. The lens obtained by this design has better resolution and contrast and smaller field curvature. At the same time, the aperture 3 of this application can be connected to the front lens group 1 or the rear lens group 2, which is beneficial to enriching the structural diversity of this lens.

[0028] Please continue reading. Figure 1 and Figure 2Furthermore, the front lens group 1 includes a first lens group 11, a second lens group 12, a third lens group 13 and a fourth lens group 14 arranged sequentially along the light incident direction. The first lens group 11 includes a first lens 111, the second lens group 12 includes a second lens 121 and a third lens 122 that are closely attached, the third lens group 13 includes a fourth lens 131 and a fifth lens 132 that are closely attached, and the fourth lens group 14 includes a sixth lens 141 and a seventh lens 142 that are closely attached.

[0029] Furthermore, the rear lens group 2 includes a fifth lens group 21, a sixth lens group 22, a seventh lens group 23, and an eighth lens group 24 arranged sequentially along the incident direction of light. The fifth lens group 21 includes an eighth lens 211 and a ninth lens 212 that are closely attached to each other. The sixth lens group 22 includes a tenth lens 221. The seventh lens group 23 includes an eleventh lens 231 and a twelfth lens 232 that are closely attached to each other. The eighth lens group 24 includes a thirteenth lens 241, which is an aspherical lens.

[0030] It is understood that the embodiments of the present invention optimize the lens structure by combining eight groups of thirteen lenses in total, wherein the front lens group 1 includes four groups of seven lenses and the rear lens group 2 includes four groups of six lenses.

[0031] Furthermore, the second lens group 12, the third lens group 13, the fourth lens group 14, the fifth lens group 21, and the seventh lens group 23 are bonded together by adhesive bonding. Adhesive bonding is a common technique in the industry and will not be elaborated here.

[0032] Furthermore, the second lens 121, the fifth lens 132, the sixth lens 141, the ninth lens 212, the tenth lens 221 and the eleventh lens 231 are positive lenses, while the first lens 111, the third lens 122, the fourth lens 131, the seventh lens 142, the eighth lens 211 and the twelfth lens 232 are negative lenses.

[0033] Specifically, in this embodiment, the second lens 121, the fifth lens 132, the sixth lens 141, the ninth lens 212, the tenth lens 221, and the eleventh lens 231 are positive lenses convex to the object side, the first lens 111 is a negative lens convex to the object side, the third lens 122, the fourth lens 131, the seventh lens 142, the eighth lens 211, and the twelfth lens 232 are negative lenses concave to the object side, and the thirteenth lens is an aspherical lens convex to the object side.

[0034] Understandably, the lens group of the present invention employs a variety of lenses, and optimizes the lens structure by combining positive lenses, negative lenses, and aspherical lenses.

[0035] Furthermore, the focal length of the rear lens group 2 is shorter than that of the front lens group 1.

[0036] Furthermore, aspherical lenses include concave and convex surfaces, and the convex surface of an aspherical lens satisfies the following formula: , indicating the full diameter of the convex surface. This represents the radius of the convex surface; the concave surface of an aspherical lens satisfies the following formula: , indicating the full diameter of the concave surface. Indicates the radius of the concave surface.

[0037] Please see Figure 3 Furthermore, the interval between the first lens group 11 and the second lens group 12 is 5.00~6.00mm; and / or, the interval between the second lens group 12 and the third lens group 13 is 16.00~17.00mm; and / or, the interval between the third lens group 13 and the fourth lens group 14 is 0~1.00mm; and / or, the interval between the fifth lens group 21 and the sixth lens group 22 is 0~1.00mm; and / or, the interval between the sixth lens group 22 and the seventh lens group 23 is 0~1.00mm; and / or, the interval between the seventh lens group 23 and the eighth lens group 24 is 1.00~2.00mm.

[0038] Furthermore, the refractive index of the first lens 111 is in the range of 1.55 to 1.62; and / or, the refractive index of the second lens 121 is in the range of 1.45 to 1.55; and / or, the refractive index of the third lens 122 is in the range of 1.65 to 1.75; and / or, the refractive index of the fourth lens 131 is in the range of 1.65 to 1.75; and / or, the refractive index of the fifth lens 132 is in the range of 1.85 to 1.95; and / or, the refractive index of the sixth lens 141 is in the range of 1.85 to 1.95; and / or, the refractive index of the seventh lens 142 is... The refractive index ranges from 1.75 to 1.85; and / or, the refractive index range of the eighth lens 211 is 1.70 to 1.80; and / or, the refractive index range of the ninth lens 212 is 1.65 to 1.75; and / or, the refractive index range of the tenth lens 221 is 1.95 to 2.05; and / or, the refractive index range of the eleventh lens 231 is 1.65 to 1.75; and / or, the refractive index range of the twelfth lens 232 is 1.75 to 1.85; and / or, the refractive index range of the thirteenth lens 241 is 1.75 to 1.85.

[0039] Furthermore, the Abbe number of the first lens 111 ranges from 59 to 61; and / or, the Abbe number of the second lens 121 ranges from 80 to 83; and / or, the Abbe number of the third lens 122 ranges from 28 to 31; and / or, the Abbe number of the fourth lens 131 ranges from 48 to 50; and / or, the Abbe number of the fifth lens 132 ranges from 38 to 40; and / or, the Abbe number of the sixth lens 141 ranges from 30 to 32; and / or, the Abbe number of the seventh lens 142 ranges from 59 to 61. The Abbe number ranges from 24 to 26; and / or, the Abbe number range of the eighth lens 211 is 26 to 28; and / or, the Abbe number range of the ninth lens 212 is 48 to 50; and / or, the Abbe number range of the tenth lens 221 is 24 to 26; and / or, the Abbe number range of the eleventh lens 231 is 48 to 50; and / or, the Abbe number range of the twelfth lens 232 is 24 to 26; and / or, the Abbe number range of the thirteenth lens 241 is 40 to 42.

[0040] For further information, please refer to [link / reference]. Figure 3 The first lens 111 has an incident surface radius of 73.212 and an exit surface radius of 33; and / or, the second lens 121 has an incident surface radius of 70; and / or, the third lens 122 has an incident surface radius of -199.67 and an exit surface radius of 26; and / or, the fourth lens 131 has an incident surface radius of -33.821; and / or, the fifth lens 132 has an incident surface radius of 70 and an exit surface radius of -57.6939; and / or, the sixth lens 141 has an incident surface radius of 44.303; and / or, the seventh lens 142 has an incident surface radius of -37.0242 and an exit surface radius of -273. .27; and / or, the incident spherical radius of the eighth lens 211 is -27.026; and / or, the incident spherical radius of the ninth lens 212 is 27.026, and the exit spherical radius is -69.3; and / or, the incident spherical radius of the tenth lens 221 is 37.544, and the exit spherical radius is -107; and / or, the incident spherical radius of the eleventh lens 231 is 27.393; and / or, the incident spherical radius of the twelfth lens 232 is -23.53, and the exit spherical radius is 27; and / or, the incident spherical radius of the twelfth lens 232 is 72.6400379131646, and the exit spherical radius is 265.33.

[0041] It should be noted that the two lenses used in the same lens group are in close contact, so the spherical radius of their mating surfaces is set to be the same numerically, therefore one of them is omitted in the table.

[0042] Please combine Figures 3 to 5It is understandable that this invention optimizes the spacing between lenses, the refractive index of the lens, and the Abbe number range to achieve superior performance in this lens. When the aperture is between 0.8 and 1.1, the lens focal length is 16.9mm, the lens distortion is small, and the MTF (modulation transfer function) of 10 line pairs is greater than 0.9 at the optimal object distance, and the MTF of 30 line pairs is greater than 0.75.

[0043] Please continue reading. Figure 4 , Figure 4 The MTF curve of the lens provided in the first embodiment of the invention is shown in the figure. The vertical axis of the figure represents the percentage of the image quality that is close to the actual object, from 0 to 1, that is, 0 to 100%. The horizontal axis of the figure represents the radius of the lens imaging plane from the center to the edge from left to right. The leftmost is zero, which is the center of the lens, and the rightmost is the edge of the image field. The maximum value depends on the size of the lens image field. The unit of measurement is millimeters.

[0044] The four markings on the right side of the figure represent four test objects. It should be noted that at positions away from the center of the image field, the MTF values ​​measured by sinusoidal gratings along the tangent direction and along the diameter direction are different. Therefore, the MTF curve generated by the line parallel to the diameter is usually called the sagittal curve, while the MTF curve generated by the line perpendicular to the tangent is called the meridional curve.

[0045] Specifically, the four objects tested in this embodiment are the 10-line-to-sagittal curve 41, denoted as 10LP / MM (sagittal), the 10-line-to-meridian curve 42, denoted as 10LP / MM (meridional), the 30-line-to-sagittal curve 43, denoted as 30LP / MM (sagittal), and the 30-line-to-meridian curve 44, denoted as 30LP / MM (meridional).

[0046] Please continue reading. Figure 4 As can be seen from the figure, the attenuation of the 10-line to sagittal curve 41 and the 10-line to meridional curve is not significant. In particular, the 10-line to sagittal curve 41 can maintain an MTF value of over 0.9 within a radius of 36 mm; while the attenuation of the 10-line to meridional curve is also very slight within a radius of 25 mm.

[0047] The attenuation of the 30-line relative to the sagittal curve 43 and the 30-line meridian curve 44 is also relatively gradual.

[0048] Please combine Figure 1 and Figure 5 , Figure 5 The field curvature and distortion curves of the lens provided in the first embodiment of the present invention show that the distortion of the lens is less than 2.5%.

[0049] Furthermore, the lens has a focal length of 16.9mm and an aperture of F0.90~F1.05.

[0050] Specifically, in this embodiment, the lens has a focal length of 16.9mm and an aperture of F0.95.

[0051] Furthermore, the lens also includes a housing assembly, with the front lens group 1 connected to the housing assembly, the rear lens group 2 being a focusing group, and the aperture 3 connected to the rear lens group 2, which can move with the rear lens group 2.

[0052] Understandably, by moving the aperture stop 3 synchronously with the rear lens group 2, the breathing effect during use can be effectively reduced, making the lens nearly free of breathing effect during use. In other embodiments, the front lens group 1 can also be set as the focusing group.

[0053] It should be noted that in practical applications, the lens in the front lens group 1 is usually fixed by a housing, and the lens in the rear lens group 2 is fixed by another housing. The aperture stop 3 is set on the housing of the front lens group 1 or the rear lens group 2 respectively. The distance between the front lens group 1 and the rear lens group 2 is adjusted by adjusting the distance between the two housings along the incident light line, thereby zooming.

[0054] The aperture stop 3 is a structure in the lens used to control the amount of light passing through. In this invention, it is sufficient to ensure that it is set between the front lens group 1 and the rear lens group 2. Whether it is connected to the front lens group 1 or the rear lens group 2, the purpose of controlling the amount of light passing through can be achieved.

[0055] Compared with the prior art, the lens of the present invention has the following advantages: 1. The lens of the present invention has a front lens group and a rear lens group, and four lens groups are respectively set in the front and rear lens groups. Then, the lens in the rear lens group located at the end far from the front lens group is set as an aspherical lens. The lens obtained by this design has better resolution and contrast and smaller field curvature. At the same time, the aperture of the present application can be connected to the front lens group or the rear lens group, which is conducive to enriching the structural diversity of the lens.

[0056] 2. This invention uses a lens structure consisting of eight groups of thirteen lenses to form the lens, thereby optimizing the lens structure. The front lens group consists of four groups of seven lenses, and the rear lens group consists of four groups of six lenses.

[0057] 3. The lens group of the present invention uses a variety of lenses, and optimizes the lens structure by combining positive lenses, negative lenses and aspherical lenses.

[0058] 4. By optimizing the spacing between lenses, the refractive index of the lens, and the Abbe number range, this invention enables the lens to achieve superior performance. When the aperture is between 0.8 and 1.1, the lens focal length is 19 to 21 mm, the lens distortion is small, and the MTF of 10 line pairs is greater than 0.9 at the optimal object distance, and the MTF of 30 line pairs is greater than 0.75.

[0059] 5. This invention provides a lens with excellent performance, featuring a focal length of 16.9mm and an aperture of F0.95, through the careful design and combination of multiple lenses.

[0060] 6. In this invention, the lens also includes a housing assembly, the front lens group is connected to the housing assembly, the rear lens group is a focusing group, the aperture is connected to the rear lens group, and the aperture can move with the rear lens group; it can be understood that by making the aperture move synchronously with the rear lens group, the breathing effect during use can be effectively reduced, so that the lens can have an almost zero breathing effect when in use.

[0061] The foregoing has provided a detailed description of a lens disclosed in an embodiment of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention. Any modifications, equivalent substitutions, and improvements made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A lens, characterized in that: It includes a front mirror group, an aperture, and a rear mirror group arranged sequentially along the incident direction of light. The front mirror group is a fixed mirror group, and the rear mirror group is an adjustable mirror group that can move along the incident line of light. The aperture is connected to the front mirror group or the aperture is connected to the rear mirror group. The front lens group includes four lens groups, and the rear lens group includes four lens groups. Each lens group includes at least one lens. The lens in the rear lens group located at the end furthest from the front lens group is an aspherical lens. The front lens group includes a first lens group, a second lens group, a third lens group, and a fourth lens group arranged sequentially along the light incident direction. The first lens group includes a first lens. The second lens group includes a second lens and a third lens in close proximity. The third lens group includes a fourth lens and a fifth lens in close proximity. The fourth lens group includes a sixth lens and a seventh lens in close proximity. The rear lens group includes a fifth lens group, a sixth lens group, a seventh lens group, and an eighth lens group arranged sequentially along the light incident direction. The fifth lens group includes an eighth lens and a ninth lens in close proximity. The sixth lens group includes a tenth lens. The seventh lens group includes an eleventh lens and a twelfth lens in close proximity. The eighth lens group includes a thirteenth lens. The lens has 13 lenses with optical power. The lens parameters are shown in the table below. In the table, parameter r1 represents the incident light radius, parameter r2 represents the exit light radius, and the units of parameters d, r1, and r2 are millimeters.

2. The lens as described in claim 1, characterized in that: The focal length of the rear lens group is less than the focal length of the front lens group.

3. The lens as described in claim 1, characterized in that: The lens also includes a housing assembly, the front lens group is connected to the housing assembly, the rear lens group is a focusing group, the aperture is connected to the rear lens group, and the aperture can move with the rear lens group.

Images