Zoom lens

Abstract

The zoom lens comprises a system front group and a system rear group which are sequentially arranged from an object plane to an image plane along an optical axis, the system front group has negative focal power, and the system rear group has positive focal power; the whole zoom lens forms a reverse long-distance structure, so that the rear working distance of the zoom lens can be effectively improved, and the space requirement of a structural member of the zoom lens is met. Meanwhile, the long working distance is favorable for improving the edge illumination of the zoom lens, so that the zoom lens can achieve uniform image brightness under the condition of a 1 / 1.8 ''large image surface. Furthermore, the focal power # imgabs0 # of the front group of the system at the long focal length end and the focal power # imgabs1 # of the front group of the system at the wide-angle end meet the requirement of # imgabs2 #, so that the zoom lens has the characteristic of realizing a large aperture at the long focal length end; the focal power # imgabs3 # of the system rear group at the long focus end and the focal power # imgabs4 # of the system rear group at the wide-angle end meet # imgabs5 #, so that the motion conditions of different groups can be well reflected, the structure optimization of the zoom lens is facilitated, the cam motion mode is improved, the structure of the zoom lens is more reasonable, the production is more facilitated, and the cost is saved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of optical devices, and in particular to a zoom lens. Background Art

[0002] With the continuous advancement of science and technology and the continuous improvement of the technological level in all walks of life, society has also put forward higher and higher requirements for zoom security lenses. In terms of performance, ordinary zoom lenses have a sharp decrease in the relative aperture at the telephoto end due to the increase in focal length, resulting in a large difference in image brightness at different focal lengths and unstable image brightness. At the same time, due to technological limitations, previous zoom lenses generally have low pixels and blurred image quality.

[0003] Therefore, based on the above needs, it is necessary to develop a high-definition, large-aperture zoom security lens, so that the zoom lens has the characteristics of variable focal length, constant large aperture and high pixels. Summary of the invention

[0004] The present invention provides a zoom lens, which realizes the design of a zoom lens with higher imaging quality.

[0005] An embodiment of the present invention provides a zoom lens, comprising a system front group and a system rear group arranged in sequence from an object plane to an image plane along an optical axis, wherein the system front group has a negative optical power, and the system rear group has a positive optical power;

[0006] The optical power of the front group of the system at the wide-angle end is The optical power at the telephoto end is The optical power of the rear group of the system at the wide-angle end is The optical power at the telephoto end is

[0007] in,

[0008] Optionally, the front group of the system includes a first fixed lens group and a variable magnification lens group, and the rear group of the system includes a second fixed lens group and a compensation lens group;

[0009] The first fixed lens group has positive optical power, the variable power lens group has negative optical power, the second fixed lens group has positive optical power, and the compensation lens group has positive optical power.

[0010] Optionally, the optical power of the first fixed lens group is The optical power of the variable magnification lens group is The optical power of the second fixed lens group is The optical power of the compensation lens group is The focal length of the zoom lens at the wide-angle end is

[0011] in,

[0012] Optionally, the first fixed lens group includes a first lens, a second lens and a third lens arranged in sequence from the object plane to the image plane, the first lens has a negative optical power, the second lens has a positive optical power, and the third lens has a positive optical power;

[0013] The zoom lens group includes a fourth lens, a fifth lens and a sixth lens, the fourth lens has a negative optical power, the fifth lens has a negative optical power, and the sixth lens has a positive optical power;

[0014] The second fixed lens group includes a seventh lens, an eighth lens, a ninth lens and a tenth lens, the seventh lens has positive focal power, the ninth lens has positive focal power, and the tenth lens has negative focal power;

[0015] The compensation lens group includes an eleventh lens, a twelfth lens, a thirteenth lens and a fourteenth lens, the eleventh lens has positive focal power, the thirteenth lens has negative focal power, and the fourteenth lens has positive focal power.

[0016] Optionally, the optical power of the first lens is The optical power of the second lens is The focal power of the third lens is The optical power of the fourth lens is The optical power of the fifth lens is The optical power of the sixth lens is The optical power of the seventh lens is The optical power of the tenth lens is

[0017] in,

[0018] Optionally, the first lens and the second lens are glued together; the fifth lens and the sixth lens are glued together; and the ninth lens and the tenth lens are glued together.

[0019] Optionally, the Abbe number of the first lens is vd1, the Abbe number of the second lens is vd2, the refractive index of the third lens is nd3, the Abbe number of the third lens is vd3, the refractive index of the fifth lens is nd5, the Abbe number of the fifth lens is vd5, the refractive index of the sixth lens is nd6, the Abbe number of the sixth lens is vd6, the Abbe number of the ninth lens is vd9, and the Abbe number of the tenth lens is vd10;

[0020] Among them, vd1<28.08, vd2>72.13, nd3<1.751, vd3>72.08;

[0021] nd5<1.720, nd6>1.700, vd5>61.51, vd6<30.30;

[0022] vd9>62.00,vd10<40.00.

[0023] Optionally, the first lens includes a first object-side surface close to the object plane and a first image-side surface close to the image plane, the first object-side surface is a convex surface, and the first image-side surface is a concave surface;

[0024] The second lens comprises a second image-side surface close to the image plane, and the second image-side surface is a convex surface;

[0025] The third lens comprises a third object-side surface close to the object plane and a third image-side surface close to the image plane, the third object-side surface is a convex surface, and the third image-side surface is a concave surface;

[0026] The fourth lens comprises a fourth object-side surface close to the object plane and a fourth image-side surface close to the image plane, the fourth object-side surface is a concave surface, and the fourth image-side surface is a concave surface;

[0027] The fifth lens comprises a fifth object-side surface close to the object plane and a fifth image-side surface close to the image plane, the fifth object-side surface is a concave surface, and the fifth image-side surface is a concave surface;

[0028] The seventh lens comprises a seventh object-side surface close to the object plane, and the seventh object-side surface is a convex surface;

[0029] The eighth lens comprises an eighth object-side surface close to the object plane and an eighth image-side surface close to the image plane, the eighth object-side surface is a convex surface, and the eighth image-side surface is a concave surface;

[0030] The ninth lens comprises a ninth object-side surface close to the object plane and a ninth image-side surface close to the image plane, the ninth object-side surface is a convex surface, and the ninth image-side surface is a convex surface;

[0031] The tenth lens comprises a tenth image-side surface close to the image plane, and the tenth image-side surface is a concave surface;

[0032] The eleventh lens comprises an eleventh object-side surface close to the object plane and an eleventh image-side surface close to the image plane, the eleventh object-side surface is a convex surface, and the eleventh image-side surface is a convex surface;

[0033] The twelfth lens comprises a twelfth object-side surface close to the object plane and a twelfth image-side surface close to the image plane, the twelfth object-side surface is a concave surface, and the twelfth image-side surface is a convex surface;

[0034] The thirteenth lens comprises a thirteenth object-side surface close to the object plane and a thirteenth image-side surface close to the image plane, the thirteenth object-side surface is a concave surface, and the thirteenth image-side surface is a concave surface;

[0035] The fourteenth lens includes a fourteenth object-side surface close to the object plane and a fourteenth image-side surface close to the image plane. The fourteenth object-side surface is a convex surface, and the fourteenth image-side surface is a concave surface.

[0036] Optionally, the center thickness of the thirteenth lens is THIC 13 , the edge thickness of the thirteenth lens is EG 13 , the center thickness of the fourteenth lens is THIC 14 , the edge thickness of the fourteenth lens is EG 14 ;

[0037] Of which, 0.300 <THIC 13 / EG 13 <1.000, EG 14 / THIC 14 <1.000.

[0038] Optionally, the focal length of the zoom lens at the wide-angle end is The optical power at the telephoto end is

[0039] in,

[0040] Optionally, the F number of the zoom lens at the wide-angle end is F W , the F number at the telephoto end is F T ;

[0041] Among them, F T / F W <1.159.

[0042] Optionally, it is characterized in that F T >1.593.

[0043] Optionally, the field of view angle of the zoom lens at the telephoto end is ω T ;

[0044] Among them, ω T ≥15.369°.

[0045] Optionally, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the ninth lens, the tenth lens and the eleventh lens are all glass spherical lenses;

[0046] The eighth lens, the twelfth lens, the thirteenth lens and the fourteenth lens are all plastic aspherical lenses.

[0047] Optionally, the zoom lens further includes an aperture and a filter;

[0048] The aperture is arranged in the optical path between the front group of the system and the rear group of the system;

[0049] The filter is arranged in the optical path between the system rear group and the image plane.

[0050] The zoom lens provided by the present invention includes a system front group and a system rear group. The system front group has negative optical power, and the system rear group has positive optical power. The overall zoom lens forms an anti-telephoto structure, which can effectively increase the rear working distance of the zoom lens and meet the space requirements of the zoom lens structural parts (such as filters, base length, etc.). At the same time, the long working distance is conducive to improving the edge illumination of the zoom lens, so that the zoom lens can achieve a 1 / 1.8" large image surface, and the image brightness is also uniform. Furthermore, the optical power of the system front group at the telephoto end is With the optical power at the wide angle end satisfy This is conducive to the zoom lens to achieve a large aperture at the telephoto end; and the optical power of the system rear group at the telephoto end Optical power of the rear group at the wide angle end satisfy The optical power ratio of different focal lengths between groups can well reflect the movement conditions of different groups, which is beneficial to the structural optimization of the zoom lens, improve the cam movement mode, make the structure of the zoom lens more reasonable, more conducive to production, and save costs.

[0051] It should be understood that the content described in this section is not intended to identify the key or important features of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0053] Figure 1 A schematic diagram of the structure of the zoom lens at the wide-angle end provided in the first embodiment of the present invention;

[0054] Figure 2 A schematic diagram of the structure of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0055] Figure 3 A schematic diagram of a light fan of a zoom lens at a wide-angle end provided by Embodiment 1 of the present invention;

[0056] Figure 4 A schematic diagram of axial chromatic aberration of the zoom lens at the wide-angle end provided by the first embodiment of the present invention;

[0057] Figure 5 A schematic diagram of vertical axis chromatic aberration of the zoom lens at the wide-angle end provided by the first embodiment of the present invention;

[0058] Figure 6 A schematic diagram of a light fan of a zoom lens at a telephoto end provided by Embodiment 1 of the present invention;

[0059] Figure 7 A schematic diagram of axial chromatic aberration of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0060] Figure 8 A schematic diagram of vertical axis chromatic aberration of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0061] Fig. 9 A schematic diagram of the structure of a zoom lens at the wide-angle end provided in Embodiment 2 of the present invention;

[0062] Fig.10 A schematic diagram of the structure of a zoom lens at the telephoto end provided by Embodiment 2 of the present invention;

[0063] Fig.11 A schematic diagram of a light fan of a zoom lens at a wide-angle end provided by Embodiment 2 of the present invention;

[0064] Fig.12 A schematic diagram of axial chromatic aberration of a zoom lens at a wide-angle end provided by Embodiment 2 of the present invention;

[0065] Fig.13 A schematic diagram of vertical axis chromatic aberration of a zoom lens at a wide-angle end provided by Embodiment 2 of the present invention;

[0066] Fig.14 A schematic diagram of a light fan of a zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0067] Fig.15 A schematic diagram of axial chromatic aberration of a zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0068] Fig.16 A schematic diagram of vertical axis chromatic aberration of a zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0069] Fig.17 A schematic diagram of the structure of a zoom lens at the wide-angle end provided in Embodiment 3 of the present invention;

[0070] Fig.18 A schematic diagram of the structure of a zoom lens at the telephoto end provided by Embodiment 3 of the present invention;

[0071] Fig.19 A schematic diagram of a light fan of a zoom lens at a wide-angle end provided in Embodiment 3 of the present invention;

[0072] Fig. 20 A schematic diagram of axial chromatic aberration of a zoom lens at a wide-angle end provided in Embodiment 3 of the present invention;

[0073] Fig.21 A schematic diagram of vertical axis chromatic aberration of a zoom lens at a wide-angle end provided by Embodiment 3 of the present invention;

[0074] Fig. 22 A schematic diagram of a light fan of a zoom lens at the telephoto end provided by Embodiment 3 of the present invention;

[0075] Fig.23 A schematic diagram of axial chromatic aberration of a zoom lens at the telephoto end provided by Embodiment 3 of the present invention;

[0076] Fig.24 Schematic diagram of vertical axis chromatic aberration of a zoom lens at the telephoto end provided by Embodiment 3 of the present invention. DETAILED DESCRIPTION

[0077] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0078] Embodiment 1

[0079] Figure 1 This is a schematic diagram of the structure of the zoom lens at the wide-angle end provided in Embodiment 1 of the present invention. Figure 2 The structure diagram of the zoom lens at the telephoto end provided by the first embodiment of the present invention is as follows: Figure 1 and Figure 2As shown, the zoom lens provided in the first embodiment of the present invention comprises a system front group G1 and a system rear group G2 arranged in sequence from the object plane to the image plane along the optical axis, the system front group G1 has a negative optical power, and the system rear group G2 has a positive optical power; the optical power of the system front group G1 at the wide-angle end is The optical power at the telephoto end is The optical power of the rear group G2 at the wide angle end is The optical power at the telephoto end is in,

[0080]

[0081] Specifically, the system front group G1 can be understood as a combination of multiple lenses located in the front part of the optical path structure of the zoom lens, and the system rear group G2 can be understood as a combination of multiple lenses located in the rear part of the optical path structure of the zoom lens.

[0082] Furthermore, the focal length is equal to the difference between the convergence degree of the image plane light beam and the convergence degree of the object plane light beam, which characterizes the ability of the zoom lens to deflect light. The larger the absolute value of the focal length is, the stronger the ability to bend light is, and the smaller the absolute value of the focal length is, the weaker the ability to bend light is. When the focal length is a positive number, the refraction of light is convergent; when the focal length is a negative number, the refraction of light is divergent. The focal length can be used to characterize a certain refractive surface of a lens (i.e., a surface of a lens), can be used to characterize a certain lens, and can also be used to characterize a zoom lens (i.e., a lens group) formed by multiple lenses. In an embodiment of the present invention, the system front group G1 has a negative focal length, and the system rear group G2 has a positive focal length. In this way, the system front group G1 and the system rear group G2 constitute an anti-telephoto structure as a whole, which can effectively increase the rear working distance of the zoom lens and meet the space requirements of the zoom lens structural components (such as filters, base length, etc.). At the same time, the long working distance is conducive to improving the edge illumination of the zoom lens, so that the zoom lens can achieve a 1 / 1.8" large image surface with uniform image brightness.

[0083] Furthermore, the optical power of the front group G1 at the wide angle end With the optical power at the telephoto end Satisfaction between This is more conducive to the zoom lens to achieve a large aperture at the telephoto end. Specifically, in the embodiment of the present invention, the F number of the zoom lens at the telephoto end is F T , where F T >1.593, which means that the zoom lens has the characteristics of large aperture at the telephoto end, which is conducive to improving the image brightness and image quality at the telephoto end. At the same time, the optical power of the rear group G2 at the wide-angle end With the optical power at the telephoto end satisfy The optical power ratio of the system front group G1 and the system rear group G2 at different focal lengths can well reflect the movement conditions of different groups, which is beneficial to the optimization of the zoom lens structure, improving the cam movement mode, making the zoom lens structure more reasonable, more conducive to production, and saving costs.

[0084] Based on the above embodiments, continue to refer to Figure 1 and Figure 2 As shown, the zoom lens further includes an aperture STO and a filter 115; the aperture STO is arranged in the optical path between the system front group G1 and the system rear group G2; the filter 115 is arranged in the optical path between the system rear group G3 and the image plane.

[0085] Specifically, by setting the aperture STO, the propagation direction of the light beam can be adjusted, which is beneficial to improving the imaging quality. And the aperture STO in the zoom lens can be located in the optical path between the system front group G1 and the system rear group G2, with the purpose of controlling the high-order aberrations of the lens at the front end of the lens, ensuring that the image height is increased and the target surface is expanded at the rear end of the lens while also having good image quality. Furthermore, the filter 115 is arranged in the optical path between the system rear group G2 and the image plane, and the filter 115 can filter out interference light and improve the imaging effect of the zoom lens. Furthermore, the zoom lens provided in an embodiment of the present invention may also include a protective glass and an image acquisition element, and the protective glass can be arranged on the image side of the filter, and the image acquisition element can be arranged on the image side of the protective glass. The optical system is protected by the protective glass, and the image is acquired by the image acquisition element, so as to realize the normal imaging function of the optical system.

[0086] Based on the above embodiments, continue to refer to Figure 1 and Figure 2 As shown, the system front group G1 includes a first fixed lens group S1 and a zoom lens group S2, and the system rear group G2 includes a second fixed lens group S3 and a compensation lens group S4; the first fixed lens group S1 has positive optical power, the zoom lens group S2 has negative optical power, the second fixed lens group S3 has positive optical power, and the compensation lens group S4 has positive optical power.

[0087] Specifically, in the zoom lens provided in this embodiment, the first fixed lens group S1, the variable power lens group S2, the second fixed lens group S3 and the compensation lens group S4 can be arranged in one lens barrel ( Figure 1 and Figure 2 The first fixed lens group S1 and the second fixed lens group S3 are fixed in the lens barrel, and the variable-power lens group S2 and the compensating lens group S4 can move back and forth along the optical axis in the lens barrel. Through the movement of the variable-power lens group S2 and the compensating lens group S4, the focal length of the zoom lens can be continuously changed from wide angle to telephoto, ensuring that the zoom lens has high image quality at each focal position.

[0088] It can be understood that in the process of zooming by moving the zoom lens group S2, the zoom lens is located at the wide-angle end when the focal length is shortest, and is located at the telephoto end when the focal length is longest. At the wide-angle end and the telephoto end, the zoom lens has different focal lengths and different lengths or shapes.

[0089] Furthermore, the first fixed lens group S1 has positive focal power, which can compress the overall light aperture at the telephoto end and increase the field of view at the telephoto end. Specifically, the field of view of the zoom lens provided by the embodiment of the present invention at the telephoto end is ω T , where ω T ≥15.369°, ensuring that the zoom lens has a good imaging field of view at the telephoto end and ensuring the imaging quality. Furthermore, the zoom lens group S2 has a negative focal length, which can expand the axial light aperture, increase the relative aperture at the wide-angle end, and achieve the characteristics of a large aperture. The second fixed lens group S3 has a positive focal length, which can well optimize the axial aberration and vertical axis aberration of the zoom lens at different focal lengths, and improve the imaging quality of the zoom lens. The compensation lens group S4 has a positive focal length, which is used to optimize the off-axis aberration and vertical axis chromatic aberration of the zoom lens, and improve the imaging quality of different focal lengths and different fields of view.

[0090] Based on the above embodiment, the optical power of the first fixed lens group S1 is The optical power of the zoom lens group S2 is The optical power of the second fixed lens group S3 is The optical power of the compensation lens group S4 is The focal length of a zoom lens at the wide angle end is in, A certain optical focal ratio can adjust the structure of the zoom lens very well, making the light change smoothly from the wide-angle end to the telephoto end of the zoom lens, which is beneficial to reducing the aberration of the zoom lens, improving the overall image quality of the zoom lens, and achieving good resolution at different focal ends.

[0091] On the basis of the above embodiment, the first fixed lens group S1 includes a first lens 101, a second lens 102 and a third lens 103 arranged in sequence from the object plane to the image plane, the first lens 101 has a negative focal power, the second lens 102 has a positive focal power, and the third lens 103 has a positive focal power; the variable power lens group S2 includes a fourth lens 104, a fifth lens 105 and a sixth lens 106, the fourth lens 104 has a negative focal power, the fifth lens 105 has a negative focal power, and the sixth lens 106 has a positive focal power; The second fixed lens group S3 includes a seventh lens 107, an eighth lens 108, a ninth lens 109 and a tenth lens 110, the seventh lens 107 has positive focal power, the ninth lens 109 has positive focal power, and the tenth lens 110 has negative focal power; the compensation lens group S4 includes an eleventh lens 111, a twelfth lens 112, a thirteenth lens 113 and a fourteenth lens 114, the eleventh lens 111 has positive focal power, the thirteenth lens 113 has negative focal power, and the fourteenth lens 114 has positive focal power.

[0092] Specifically, the first lens 101 is a negative power lens. The first lens 101 with negative power in the front can reduce the inclination angle of the off-axis light beam. In addition to optimizing the chromatic aberration caused by the first fixed lens group S1 itself, it can also effectively reduce the aberration of the off-axis field of view. The second lens 102 and the third lens 103 are both positive power lenses. In this way, the second lens 102 and the third lens 103 can realize timely correction of the larger aberration generated by the first lens 101, especially can have a significant correction effect on the edge aberration of the zoom lens, thereby improving the imaging resolution of the zoom lens. In addition, the setting of the negative power of the first lens 101, the positive power of the second lens 102 and the positive power of the third lens 103 ensures that the positive power of the first fixed lens group S1 can be set. Further, the setting of the negative focal power of the fourth lens 104, the negative focal power of the fifth lens 105, and the positive focal power of the sixth lens 106 ensures that the setting of the negative focal power of the zoom lens group S2 can be achieved, and the setting of the negative focal power of the fourth lens 104 can neutralize the negative spherical aberration caused by the setting of the positive focal power of the first fixed lens group S. Further, the setting of the positive focal power of the seventh lens 107, the positive focal power of the ninth lens 109, and the negative focal power of the tenth lens 110 can achieve the setting of the positive focal power of the second fixed lens group S3. The setting of the positive focal power of the eleventh lens 111, the negative focal power of the thirteenth lens 113, and the positive focal power of the fourteenth lens 114 can achieve the setting of the positive focal power of the compensation lens group S4. Further, the eighth lens 108 and the twelfth lens 112 are both lenses with focal power, and the focal power of the two lenses can be positive or negative, which is not limited in the embodiment of the present invention.

[0093] Based on the above embodiment, the optical power of the first lens 101 is The optical power of the second lens 102 is The optical power of the third lens 103 is The optical power of the fourth lens 104 is The optical power of the fifth lens 105 is The optical power of the sixth lens 106 is The optical power of the seventh lens 107 is The optical power of the tenth lens 110 is in,

[0094] Specifically, the maximum optical power absolute value among the first lens 101, the second lens 102 and the third lens 103 is in Appropriate optical power can reduce the contribution of a single lens to zoom lens aberrations.

[0095] Furthermore, the absolute value of the minimum optical power among the fourth lens 104, the fifth lens 105 and the sixth lens 106 is in A certain optical focal length can better improve the system's zoom ratio and relative aperture.

[0096] Furthermore, the optical power of the seventh lens element 107 is satisfy Appropriate optical power can converge the aperture angle brought by the front group G1 of the system and reduce the volume of the rear group G2 of the system.

[0097] Furthermore, the optical power of the tenth lens 110 is satisfy In this way, the influence of the chromatic aberration of the second fixed lens group S3 on the zoom lens can be well reduced, which is conducive to the zoom lens to achieve the infrared confocal feature.

[0098] Based on the above embodiments, continue to refer to Figure 1 and Figure 2 As shown, the first lens 101 and the second lens 102 are cemented together; the fifth lens 105 and the sixth lens 106 are cemented together; and the ninth lens 109 and the tenth lens 110 are cemented together.

[0099] Specifically, the first lens 101 and the second lens 102 are bonded together, which can be understood as the surface of the first lens 101 close to the image side is bonded to the surface of the second lens 102 close to the object plane, that is, the image side surface of the first lens 101 is bonded to the object side surface of the second lens 102. The fifth lens 105 and the sixth lens 106 are bonded together, which can be understood as the surface of the fifth lens 105 close to the image side is bonded to the surface of the sixth lens 106 close to the object plane, that is, the image side surface of the fifth lens 105 is bonded to the object side surface of the sixth lens 106. The ninth lens 109 and the tenth lens 110 are bonded together, which can be understood as the surface of the ninth lens 109 close to the image side is bonded to the surface of the tenth lens 110 close to the object plane, that is, the image side surface of the ninth lens 109 is bonded to the object side surface of the tenth lens 110. By setting the first lens 101 and the second lens 102 to be glued together, the air gap between the first lens 101 and the second lens 102 can be reduced, the air gap between the fifth lens 105 and the sixth lens 105 can be reduced by setting the fifth lens 105 and the sixth lens 105 to be glued together, and the air gap between the ninth lens 109 and the tenth lens 110 can be reduced by setting the ninth lens 109 and the tenth lens 110 to be glued together, and all of them are helpful to reduce the total optical length of the lens, and can also reduce the tolerance sensitivity problems such as tilt / eccentricity generated by the lens unit during the assembly process, simplify the assembly procedures in the lens manufacturing process, and improve equipment efficiency. At the same time, the glued arrangement of the first lens 101 and the second lens 102, the glued arrangement of the fifth lens 105 and the sixth lens 105, and the glued arrangement of the ninth lens 109 and the tenth lens 110 can also reduce the light loss caused by reflection between lenses, improve illumination, and reduce the risk of ghosting. Furthermore, the cemented lens can be used to minimize or eliminate chromatic aberration. The use of the cemented lens in the zoom lens can improve the image quality and reduce the reflection loss of light energy, thereby improving the image quality and enhancing the clarity of the lens imaging. Furthermore, the cemented arrangement between the first lens 101 and the second lens 102, between the fifth lens 105 and the sixth lens 106, and between the ninth lens 109 and the tenth lens 110 can be supported by a gasket or can be bonded by glue. The embodiment of the present invention does not limit the specific bonding method.

[0100] On the basis of the above embodiment, the Abbe number of the first lens 101 is vd1, the Abbe number of the second lens 102 is vd2, the refractive index of the third lens 103 is nd3, the Abbe number of the third lens 103 is vd3, the refractive index of the fifth lens 105 is nd5, the Abbe number of the fifth lens 105 is vd5, the refractive index of the sixth lens 106 is nd6, the Abbe number of the sixth lens 106 is vd6, the Abbe number of the ninth lens 109 is vd9, and the Abbe number of the tenth lens 110 is vd10; wherein, vd1<28.08, vd2>72.13, nd3<1.751, vd3>72.08; nd5<1.720, nd6>1.700, vd5>61.51, vd6<30.30; vd9>62.00, vd10<40.00.

[0101] Specifically, vd1<28.08, vd2>72.13, nd3<1.751, vd3>72.08, nd5<1.720, nd6>1.700, vd5>61.51, vd6<30.30 are set. Such low refractive index materials combined with high Abbe numbers can reduce the influence of single lenses on the chromatic aberration of the zoom lens, so that the zoom lens can not only achieve chromatic aberration correction in the visible light band, but also reduce the axial chromatic aberration in the infrared band, which is conducive to the zoom lens to achieve the infrared confocal feature. Further, vd9>62.00, vd10<40.00 are set, which can well reduce the influence of the chromatic aberration of the second fixed lens group S3 on the zoom lens, which is conducive to the zoom lens to achieve the infrared confocal feature.

[0102] Based on the above embodiments, continue to refer to Figure 1 and Figure 2As shown, the first lens 101 includes a first object-side surface close to the object plane and a first image-side surface close to the image plane, the first object-side surface is convex, and the first image-side surface is concave; the second lens 102 includes a second image-side surface close to the image plane, and the second image-side surface is convex; the third lens 103 includes a third object-side surface close to the object plane and a third image-side surface close to the image plane, the third object-side surface is convex, and the third image-side surface is concave; the fourth lens 104 includes a fourth object-side surface close to the object plane and a fourth image-side surface close to the image plane, the fourth object-side surface is concave, and the fourth image-side surface is concave; the fifth lens 105 includes a fifth object-side surface close to the object plane and a fifth image-side surface close to the image plane, the fifth object-side surface is concave, and the fifth image-side surface is concave; the seventh lens 107 includes a seventh object-side surface close to the object plane, and the seventh object-side surface is convex; the eighth lens 108 includes an eighth object-side surface close to the object plane and an eighth image-side surface close to the image plane, the eighth object-side surface is convex, and the eighth image-side surface is concave. The image side surface is concave; the ninth lens 109 includes a ninth object side surface close to the object plane and a ninth image side surface close to the image plane, the ninth object side surface is convex, and the ninth image side surface is convex; the tenth lens 110 includes a tenth image side surface close to the image plane, and the tenth image side surface is concave; the eleventh lens 111 includes an eleventh object side surface close to the object plane and an eleventh image side surface close to the image plane, the eleventh object side surface is convex, and the eleventh image side surface is convex; the twelfth lens 112 includes a twelfth object side surface close to the object plane and a twelfth image side surface close to the image plane, the twelfth object side surface is concave, and the twelfth image side surface is convex; the thirteenth lens 113 includes a thirteenth object side surface close to the object plane and a thirteenth image side surface close to the image plane, the thirteenth object side surface is concave, and the thirteenth image side surface is concave; the fourteenth lens 114 includes a fourteenth object side surface close to the object plane and a fourteenth image side surface close to the image plane, the fourteenth object side surface is convex, and the fourteenth image side surface is concave.

[0103] Specifically, the object side of the lens can be understood as the surface of the lens on the side close to the object plane, and the image side of the lens can be understood as the surface of the lens on the side close to the image plane. The first object side is a convex surface, and the first image side is a concave surface, that is, the object side of the first lens 101 is convex toward the object plane at the near optical axis position, and the image side is concave toward the image plane at the near optical axis position, that is, the first lens 102 is a lens of a convex-concave structure. The second image side is a convex surface, that is, the image side of the second lens 102 is convex toward the image plane at the near optical axis position. The third object side is a convex surface, and the third image side is a concave surface, that is, the object side of the third lens 103 is convex toward the object plane at the near optical axis position, and the image side is concave toward the image plane at the near optical axis position, that is, the third lens 103 is a lens of a convex-concave structure. The fourth object side is a concave surface, and the fourth image side is a concave surface, that is, the object side of the fourth lens 104 is concave toward the object plane at the near optical axis position, and the image side is concave toward the image plane at the near optical axis position, that is, the fourth lens 104 is a lens of a double concave structure. The fourth lens 104 is biconcave on the object-image side, which can reduce its own spherical aberration. The fifth object-side surface is concave, and the fifth image-side surface is concave, that is, the object-side surface of the fifth lens 105 is concave toward the object surface at the near optical axis position, and the image-side surface is concave toward the image surface at the near optical axis position, that is, the fifth lens 105 is a lens with a biconcave structure. The fifth lens 105 is of the same shape as the fourth lens 104, and is glued with the sixth lens 106, which can reduce the magnification chromatic aberration and position chromatic aberration of the zoom lens group S2, and is conducive to reducing the resolution difference of visible light and infrared light at different focal lengths.

[0104] The seventh object side surface is a convex surface, that is, the object side surface of the seventh lens 107 is convex toward the object plane at the near optical axis position. The eighth image side surface is a convex surface, and the eighth image side surface is a concave surface, that is, the object side surface of the eighth lens 108 is convex toward the object plane at the near optical axis position, and the image side surface is concave toward the image plane at the near optical axis position, that is, the eighth lens 108 is a lens of a convex-concave structure. The ninth object side surface is a convex surface, and the ninth image side surface is a convex surface, that is, the object side surface of the ninth lens 109 is convex toward the object plane at the near optical axis position, and the image side surface is convex toward the image plane at the near optical axis position, that is, the ninth lens 109 is a lens of a double convex structure. The tenth image side surface is a concave surface, that is, the image side surface of the tenth lens 110 is concave toward the image plane at the near optical axis position. The eleventh object side surface is a convex surface, and the eleventh image side surface is a convex surface, that is, the object side surface of the eleventh lens 111 is convex toward the object plane at the near optical axis position, and the image side surface is convex toward the image plane at the near optical axis position, that is, the eleventh lens 111 is a lens of a double convex structure. The surface shape of the eleventh lens 111 combined with its positive optical power setting can reduce the spherical aberration of the compensation lens group. The twelfth image side surface is a concave surface, and the twelfth image side surface is a convex surface, that is, the object side surface of the twelfth lens 112 is concave toward the object plane at the near optical axis position, and the image side surface is convex toward the image plane at the near optical axis position, that is, the twelfth lens 112 is a lens with a concave-convex structure. The shape design of the concave-convex structure of the twelfth lens 112 is combined with the double convex structure design of the eleventh lens 111, which can further reduce the influence of spherical aberration on the system, thereby improving the coma of the system. The thirteenth image side surface is a concave surface, and the thirteenth image side surface is a concave surface, that is, the object side surface of the thirteenth lens 113 is concave toward the object plane at the near optical axis position, and the image side surface is concave toward the image plane at the near optical axis position, that is, the thirteenth lens 113 is a lens with a double concave structure. The fourteenth image side surface is a convex surface, and the fourteenth image side surface is a concave surface, that is, the object side surface of the fourteenth lens 114 is convex toward the object plane at the near optical axis position, and the image side surface is concave toward the image plane at the near optical axis position, that is, the fourteenth lens 114 is a lens with a convex-concave structure. Through the surface design of each lens mentioned above, combined with the optical power of each lens, the imaging effect of the zoom lens can be further adjusted.

[0105] Based on the above embodiment, the center thickness of the thirteenth lens 113 is THIC 13 , the edge thickness of the thirteenth lens 113 is EG 13 , the center thickness of the fourteenth lens 114 is THIC 14 , the edge thickness of the fourteenth lens 114 is EG 14 ; Among them, 0.300 <THIC 13 / EG 13 <1.000, EG 14 / THIC 14 <1.000. This setting is helpful to optimize the system's off-axis field of view resolution and improve the system's image quality.

[0106] Based on the above embodiment, the focal length of the zoom lens at the wide-angle end is The optical power at the telephoto end is in, This is conducive to realizing the large zoom ratio feature of the zoom lens.

[0107] Based on the above embodiment, the F number of the zoom lens at the wide angle end is F W , the F number at the telephoto end is F T ; Among them, F T / F W <1.159, which is conducive to achieving the constant aperture characteristic of zoom lenses at different focal lengths, ensuring that the image brightness difference at different focal lengths is small and the image brightness stability is high.

[0108] Based on the above embodiments, the first lens 101, the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 105, the sixth lens 106, the seventh lens 107, the ninth lens 109, the tenth lens 110 and the eleventh lens 111 are all glass spherical lenses; the eighth lens 108, the twelfth lens 112, the thirteenth lens 113 and the fourteenth lens 114 are all plastic aspherical lenses.

[0109] Specifically, the spherical lens is characterized by having a constant curvature from the center of the lens to the periphery of the lens, which ensures that the lens is set in a simple manner. Furthermore, since the thermal expansion coefficient of the glass lens is small and the stability is good, the first lens 101, the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 105, the sixth lens 106, the seventh lens 107, the ninth lens 109, the tenth lens 110 and the eleventh lens 111 can be set to be glass spherical lenses. The thermal properties of glass spherical lenses are more stable, and when they bear more optical power, they can ensure that the lens has good resolution within a wider temperature range. In addition, compared with plastic aspherical lenses, the range of glass materials available is wider, and the refractive index and Abbe number are relatively free to choose. To a certain extent, the high-order aberrations and chromatic aberrations of the lens can be controlled to meet the use requirements under complex conditions.

[0110] The characteristic of the aspheric lens is that the curvature changes continuously from the center of the lens to the periphery of the lens. Unlike the spherical lens with a constant curvature from the center of the lens to the periphery of the lens, the aspheric lens has a better curvature radius characteristic and has the advantages of improving distortion aberration and improving astigmatism aberration. On this basis, the aspheric lens can be a plastic aspheric lens, which is conducive to reducing the processing technology of the aspheric lens, and the cost of the aspheric lens is low. Setting the eighth lens to use a plastic aspheric lens can effectively optimize the high-level axial aberration and vertical axis aberration of the system, reduce the resolution difference between the axial field of view of the visible band and the infrared band, and at the same time, the appropriate aspheric lens can reduce the cost of the optical system. Setting the twelfth lens 112, the thirteenth lens 113 and the fourteenth lens 114 are all plastic aspheric lenses, which can effectively improve the resolution of the off-axis field of view, so that the system has good resolution under a large target surface of 1 / 1.8", and can reduce the resolution difference between the off-axis field of view of the visible band and the infrared band. A large amount of plastic materials can also reduce the manufacturing cost.

[0111] As a feasible implementation, the parameters of each lens in the zoom lens are described below.

[0112] Table 1 Optical design values ​​of the zoom lens in Example 1

[0113]

[0114] Table 2 Design values ​​of optical physical parameters of a zoom lens

[0115] Surface number Surface type Radius of curvature thickness nd vd / dP Semi-caliber K Value 1 Standard surface 134.735 0.576 1.588 20.00 / 0.000 9.869 0.000 2 Standard surface 66.531 1.934 1.577 95.00 / 0.000 9.755 0.000 3 Standard surface -94.111 0.277 9.668 0.000 4 Standard surface 23.696 2.252 1.448 95.00 / 0.000 9.017 0.000 5 Standard surface 65.383 -4.564 8.779 0.000 6 Standard surface INF STEP1 10.681 0.000 7 Standard surface -48.814 0.549 1.900 23.79 / 0.000 5.756 0.000 8 Standard surface 17.865 1.729 5.300 0.000 9 Standard surface -21.807 0.566 1.646 95.00 / 0.000 5.233 0.000 10 Standard surface 21.807 1.343 2.082 19.98 / 0.000 5.313 0.000 11 Standard surface -119.115 21.864 5.304 0.000 12 Standard surface INF -STEP1 10.680 0.000 13 STO INF -0.501 5.413 0.000 14 Standard surface 8.718 3.048 1.556 19.94 / 0.000 5.637 0.000 15 Standard surface 1081.859 0.353 5.637 0.000 16 even aspherical surface 15.476 0.599 1.331 95.00 / 0.000 5.068 2.018 17 even aspherical surface 10.520 0.569 4.741 1.198 18 Standard surface 8.906 3.855 1.616 95.00 / 0.000 4.669 0.000 19 Standard surface -8.140 0.562 1.788 19.92 / 0.000 4.669 0.000 20 Standard surface 7.399 -0.833 3.801 0.000 21 Standard surface INF STEP 2 3.584 0.000 22 Standard surface 9.569 2.766 1.752 95.00 / 0.000 4.010 0.000 23 Standard surface -17.875 0.056 4.010 0.000 24 even aspherical surface -26.573 4.232 1.778 19.99 / 0.000 3.935 0.000 25 even aspherical surface -12.335 0.250 4.043 -46.270 26 even aspherical surface -4.536 1.141 1.861 95.00 / 0.000 3.940 -6.949 27 even aspherical surface -25.771 0.246 3.876 34.392 28 even aspherical surface 4.614 1.002 1.951 19.97 / 0.000 4.048 -3.613 29 even aspherical surface 5.772 4.019 4.232 0.516 30 Standard surface INF -STEP2 0.000 31 Standard surface INF 0.700 1.517 64.20 / 0.000 0.000 32 Standard surface INF 2.985 0.000 33 Image plane

[0116] In the above Table 2, the surface numbers are numbered according to the order of the surfaces of each lens, "1" represents the object surface of the first lens, and "2" represents the image surface of the first lens. "STO" represents the aperture of the lens; the radius of curvature represents the degree of curvature of the lens surface, and the unit is mm. A positive value represents that the surface is bent toward the object side, and a negative value represents that the surface is bent toward the image side, where "INF" represents that the surface is a plane and the radius of curvature is infinite. Thickness represents the central axial distance from the current surface to the next surface, and the unit is mm. "nd" represents the ability of the material between the current surface and the next surface to deflect light. A blank space represents that the current position is air, and the refractive index is 1. "vd" represents the dispersion characteristics of the material between the current surface and the next surface for light, and a blank space represents that the current position is air. dPgF represents the relative partial dispersion of the material. The semi-aperture represents half of the aperture size of the current surface. The K value represents the numerical value of the cone coefficient of the aspheric surface.

[0117] Table 3 Zoom intervals at the wide-angle and telephoto ends of a zoom lens

[0118] Wide-angle end Telephoto end STEP1 5.841 21.108 STEP 2 2.809 2.003 focal length 10.821 29.755 F / # 1.693 1.770 Field of view 50.51° 17.09°

[0119] The zoom intervals in Table 3 are the different intervals at the wide-angle end and the telephoto end of the lens.

[0120] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0121]

[0122] Wherein, z is the axial sagittal height of the aspheric surface in the Z direction; r is the height of the aspheric surface; c is the curvature of the fitted spherical surface, which is the reciprocal of the curvature radius R; k is the fitted cone coefficient; a4, a6, a8, a10, a12, a14, a16 are the high-order aspheric coefficients of the corresponding aspheric surface of the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order, a i r i The combination becomes the high-order terms corresponding to the aspherical surface.

[0123] Table 4 Design values ​​of aspheric cone coefficients in a zoom lens

[0124]

[0125] "9.681E-05" means 9.681*10 -5 The remaining coefficients are expressed in this way.

[0126] Furthermore, Figure 3 This is a light fan diagram of the zoom lens provided in the first embodiment of the present invention at the wide-angle end, as shown in FIG. Figure 3 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, the vertical axis is the vertical axis aberration, and the light in the figure describes the aberration of the main light of the system. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in this field of view are focused on the same point on the image plane; the vertical axis in a single image can also be expressed as the maximum dispersion range of the light beam on the ideal image plane. It can be seen from the figure that the main wavelength of this zoom lens in each field of view is well close to the horizontal axis, indicating that the monochromatic aberration in each field of view is well corrected.

[0127] Figure 4 This is a schematic diagram of the axial chromatic aberration of the field curvature of the zoom lens provided in the first embodiment of the present invention at the wide-angle end. In the figure, the vertical direction represents the normalization of the pupil plane of the 0 field of view, 0 represents the center of the pupil, and the vertical vertex represents the vertex of the pupil; the horizontal direction is the axial chromatic aberration of different wavelengths (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm), in millimeters (mm). As can be seen in the figure, the axial chromatic aberration of the system is within the range of ±0.05mm, indicating that the system chromatic aberration is well corrected and the infrared confocal characteristics of the system can be well realized.

[0128] Figure 5This is a diagram of the vertical axis chromatic aberration of the zoom lens at the wide-angle end provided in Example 1 of the present invention. The vertical direction in the figure represents the field of view angle, 0 represents the field of view angle parallel to the optical axis, and the vertical vertex represents the maximum half field of view angle; the horizontal direction is the offset of the meridian range based on 0.546μm as the reference, in microns (μm). The numbers on the curves in the figure represent the wavelength represented by the curve, in microns (μm). As can be seen from the figure, the vertical axis chromatic aberration of each wavelength of the system (specifically 436nm, 486.1nm, 546nm, 587.6nm and 656.3nm) is within ±10μm, indicating that the system chromatic aberration is well corrected. As the angle increases, the vertical axis chromatic aberrations of each wavelength overlap, indicating that each field of view of the system has a certain degree of chromatic aberration correction.

[0129] Figure 6 This is a light fan diagram of the zoom lens provided in the first embodiment of the present invention at the telephoto end, such as Figure 6 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, the vertical axis is the vertical axis aberration, and the light in the figure describes the aberration of the main light of the system. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in this field of view are focused on the same point on the image plane; the vertical axis in a single image can also be expressed as the maximum dispersion range of the light beam on the ideal image plane. It can be seen from the figure that the main wavelength of this zoom lens in each field of view is well close to the horizontal axis, indicating that the monochromatic aberration in each field of view is well corrected.

[0130] Figure 7 This is a schematic diagram of the axial chromatic aberration of the zoom lens provided in the first embodiment of the present invention at the telephoto end. In the figure, the vertical direction represents the normalization of the pupil plane of the 0 field of view, 0 represents the center of the pupil, and the vertical vertex represents the vertex of the pupil; the horizontal direction is the axial chromatic aberration of different wavelengths (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm), in millimeters (mm). As can be seen in the figure, the axial chromatic aberration of the system is within the range of ±0.05mm, indicating that the system chromatic aberration is well corrected and the infrared confocal characteristics of the system can be well realized.

[0131] Figure 8 This is a diagram of the vertical axis chromatic aberration of the zoom lens at the telephoto end provided in Example 1 of the present invention. The vertical direction in the diagram represents the field of view angle, 0 represents the field of view angle parallel to the optical axis, and the vertical vertex represents the maximum half field of view angle; the horizontal direction is the offset of the reference meridian range with 0.546μm as the unit, in microns (μm). The numbers on the curves in the figure represent the wavelength represented by the curve, in microns (μm). As can be seen from the figure, the vertical axis chromatic aberration of each wavelength of the system (specifically 436nm, 486.1nm, 546nm, 587.6nm and 656.3nm) is within ±10μm, indicating that the system chromatic aberration is well corrected. As the angle increases, the vertical axis chromatic aberrations of each wavelength overlap, indicating that each field of view of the system has a certain degree of chromatic aberration correction.

[0132] In summary, the zoom lens provided in the first embodiment of the present invention uses a glass-plastic hybrid lens to meet the requirements of 1 / 1.8" large target surface and high-pixel imaging, and has the characteristics of infrared confocal, constant large aperture, and low cost.

[0133] Embodiment 2

[0134] Fig. 9 This is a schematic diagram of the structure of the zoom lens at the wide-angle end provided in the second embodiment of the present invention. Fig.10 This is a schematic diagram of the structure of the zoom lens at the telephoto end provided by the second embodiment of the present invention, as shown in FIG. Fig. 9 and Fig.10 As shown, the zoom lens provided by the second embodiment of the present invention comprises a system front group G1 and a system rear group G2 arranged in sequence from the object plane to the image plane along the optical axis, the system front group G1 has a negative optical power, and the system rear group G2 has a positive optical power; the optical power of the system front group G1 at the wide-angle end is The optical power at the telephoto end is The optical power of the rear group G2 at the wide angle end is The optical power at the telephoto end is in,

[0135]

[0136] The configuration of the above-mentioned lens is the same as that in the first embodiment, and will not be described in detail here.

[0137] As another feasible implementation, specific parameters in the zoom lens are described below.

[0138] Table 5 Optical design values ​​of the zoom lens in Example 2

[0139]

[0140] Table 6 Design values ​​of optical physical parameters of a zoom lens

[0141] Surface number Surface type Radius of curvature thickness nd vd / dP Semi-caliber K Value 1 Standard surface 71.304 0.579 1.676 24.730 / 0.000 10.686 0.000 2 Standard surface 33.224 2.275 1.638 80.140 / 0.000 10.469 0.000 3 Standard surface -340.162 0.285 10.401 0.000 4 Standard surface 40.168 1.625 1.592 80.090 / 0.000 9.957 0.000 5 Standard surface 116.660 -3.796 9.786 0.000 6 Standard surface INF STEP1 9.442 0.000 7 Standard surface -181.392 0.549 1.818 80.100 / 0.000 6.263 0.000 8 Standard surface 30.776 1.408 5.883 0.000 9 Standard surface -25.040 0.554 1.700 80.140 / 0.000 5.796 0.000 10 Standard surface 25.040 1.356 1.844 25.040 / 0.000 5.702 0.000 11 Standard surface 127.440 21.973 5.651 0.000 12 Standard surface INF -STEP1 6.203 0.000 13 STO INF -0.600 5.413 0.000 14 Standard surface 8.745 3.021 1.685 23.480 / 0.000 5.688 0.000 15 Standard surface 353.106 0.525 5.688 0.000 16 even aspherical surface 22.394 0.811 1.534 60.030 / 0.000 5.048 2.018 17 even aspherical surface 9.551 1.008 4.547 1.198 18 Standard surface 11.273 3.575 1.797 82.230 / 0.000 4.517 0.000 19 Standard surface -7.039 0.591 1.897 18.230 / 0.000 4.517 0.000 20 Standard surface 10.475 0.130 3.843 0.000 21 Standard surface INF STEP 2 3.810 0.000 22 Standard surface 11.920 3.023 1.811 24.680 / 0.000 4.431 0.000 23 Standard surface -33.045 0.058 4.431 0.000 24 even aspherical surface -57.845 2.106 1.625 24.730 / 0.000 4.405 0.000 25 even aspherical surface -15.276 0.303 4.388 -46.270 26 even aspherical surface -4.790 1.006 1.593 60.350 / 0.000 4.333 -6.949 27 even aspherical surface -219.281 0.249 4.146 34.392 28 even aspherical surface 4.455 1.148 1.618 24.040 / 0.000 4.213 -3.613 29 even aspherical surface 5.858 4.116 4.355 0.516 30 Standard surface INF -STEP2 0.000 31 Standard surface INF 0.700 1.517 64.200 / 0.000 0.000 32 Standard surface INF 2.985 0.000 33 Image plane

[0142] In the above Table 6, the surface numbers are numbered according to the order of the surfaces of each lens, "1" represents the object surface of the first lens, and "2" represents the image surface of the first lens. "STO" represents the aperture of the lens; the radius of curvature represents the degree of curvature of the lens surface, and the unit is mm. A positive value represents that the surface is bent toward the object side, and a negative value represents that the surface is bent toward the image side, where "INF" represents that the surface is a plane and the radius of curvature is infinite. Thickness represents the central axial distance from the current surface to the next surface, and the unit is mm. "nd" represents the ability of the material between the current surface and the next surface to deflect light. A blank space represents that the current position is air, and the refractive index is 1. "vd" represents the dispersion characteristics of the material between the current surface and the next surface for light, and a blank space represents that the current position is air. dPgF represents the relative partial dispersion of the material. The semi-aperture represents half of the aperture size of the current surface. The K value represents the numerical value of the cone coefficient of the aspheric surface.

[0143] Table 7 Zoom intervals at the wide-angle and telephoto ends of a zoom lens

[0144] Wide-angle end Telephoto end STEP1 4.614 21.108 STEP 2 3.504 2.033 focal length 11.178 29.768 F / # 1.686 1.778 Field of view 49.34° 17.08°

[0145] The zoom intervals in Table 7 are the different intervals at the wide-angle end and the telephoto end of the lens.

[0146] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0147]

[0148] Wherein, z is the axial sagittal height of the aspheric surface in the Z direction; r is the height of the aspheric surface; c is the curvature of the fitted spherical surface, which is the reciprocal of the curvature radius R; k is the fitted cone coefficient; a4, a6, a8, a10, a12, a14, a16 are the high-order aspheric coefficients of the corresponding aspheric surface of the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order, a i r i The combination becomes the high-order terms corresponding to the aspherical surface.

[0149] Table 8 Design values ​​of aspheric cone coefficients in a zoom lens

[0150]

[0151] "2.531E-04" means 2.531*10 -4 The remaining coefficients are expressed in this way.

[0152] Furthermore, Fig.11 This is a light fan diagram of the zoom lens at the wide-angle end provided by the second embodiment of the present invention, such as Fig.11As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, the vertical axis is the vertical axis aberration, and the light in the figure describes the aberration of the main light of the system. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in this field of view are focused on the same point on the image plane; the vertical axis in a single image can also be expressed as the maximum dispersion range of the light beam on the ideal image plane. It can be seen from the figure that the main wavelength of this zoom lens in each field of view is well close to the horizontal axis, indicating that the monochromatic aberration in each field of view is well corrected.

[0153] Fig.12 This is a schematic diagram of the axial chromatic aberration of the field curvature of the zoom lens provided in the second embodiment of the present invention at the wide-angle end. In the figure, the vertical direction represents the normalization of the pupil plane of the 0 field of view, 0 represents the center of the pupil, and the vertical vertex represents the vertex of the pupil; the horizontal direction is the axial chromatic aberration of different wavelengths (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm), in millimeters (mm). As can be seen in the figure, the axial chromatic aberration of the system is within the range of ±0.05mm, indicating that the system chromatic aberration is well corrected and the infrared confocal characteristics of the system can be well realized.

[0154] Fig.13 The vertical axis chromatic aberration diagram of the zoom lens at the wide-angle end provided in Example 2 of the present invention, in which the vertical direction represents the field of view angle, 0 represents the field of view angle parallel to the optical axis, and the vertical vertex represents the maximum half field of view angle; the horizontal direction is the offset of the reference meridian range with 0.546μm as the reference, in micrometers (μm). The numbers on the curves in the figure represent the wavelength represented by the curve, in micrometers (μm). As can be seen from the figure, the vertical axis chromatic aberration of each wavelength of the system (specifically 436nm, 486.1nm, 546nm, 587.6nm and 656.3nm) is within ±10μm, indicating that the system chromatic aberration is well corrected. As the angle increases, the vertical axis chromatic aberrations of each wavelength overlap, indicating that each field of view of the system has a certain degree of chromatic aberration correction.

[0155] Fig.14 This is a light fan diagram of the zoom lens at the telephoto end provided by the second embodiment of the present invention, such as Fig.14 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, the vertical axis is the vertical axis aberration, and the light in the figure describes the aberration of the main light of the system. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in this field of view are focused on the same point on the image plane; the vertical axis in a single image can also be expressed as the maximum dispersion range of the light beam on the ideal image plane. It can be seen from the figure that the main wavelength of this zoom lens in each field of view is well close to the horizontal axis, indicating that the monochromatic aberration in each field of view is well corrected.

[0156] Fig.15This is a schematic diagram of the axial chromatic aberration of the zoom lens at the telephoto end provided in the second embodiment of the present invention. In the figure, the vertical direction represents the normalization of the pupil plane of the 0 field of view, 0 represents the center of the pupil, and the vertical vertex represents the vertex of the pupil; the horizontal direction represents the axial chromatic aberration of different wavelengths (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm), in millimeters (mm). As can be seen in the figure, the axial chromatic aberration of the system is within the range of ±0.05mm, indicating that the system chromatic aberration is well corrected and the infrared confocal characteristics of the system can be well realized.

[0157] Fig.16 The vertical axis chromatic aberration diagram of the zoom lens at the telephoto end provided in Example 2 of the present invention, in which the vertical direction represents the field of view angle, 0 represents the field of view angle parallel to the optical axis, and the vertical vertex represents the maximum half field of view angle; the horizontal direction is the offset of the reference meridian range with 0.546μm as the reference, in micrometers (μm). The numbers on the curves in the figure represent the wavelength represented by the curve, in micrometers (μm). As can be seen from the figure, the vertical axis chromatic aberration of each wavelength of the system (specifically 436nm, 486.1nm, 546nm, 587.6nm and 656.3nm) is within ±10μm, indicating that the system chromatic aberration is well corrected. As the angle increases, the vertical axis chromatic aberrations of each wavelength overlap, indicating that each field of view of the system has a certain degree of chromatic aberration correction.

[0158] In summary, the zoom lens provided in the second embodiment of the present invention uses a glass-plastic hybrid lens, which meets the requirements of 1 / 1.8" large target surface and high-pixel imaging, and has the characteristics of infrared confocal, constant large aperture, and low cost.

[0159] Embodiment 3

[0160] Fig.17 This is a schematic diagram of the structure of the zoom lens at the wide-angle end provided in Embodiment 3 of the present invention. Fig.18 This is a schematic diagram of the structure of the zoom lens at the telephoto end provided by the third embodiment of the present invention, as shown in FIG. Fig.17 and Fig.18 As shown, the zoom lens provided in the third embodiment of the present invention comprises a system front group G1 and a system rear group G2 arranged in sequence from the object plane to the image plane along the optical axis, the system front group G1 has a negative optical power, and the system rear group G2 has a positive optical power; the optical power of the system front group G1 at the wide-angle end is The optical power at the telephoto end is The optical power of the rear group G2 at the wide angle end is The optical power at the telephoto end is in,

[0161]

[0162] The configuration of the above-mentioned lens is the same as that in the first embodiment, and will not be described in detail here.

[0163] As another feasible implementation, specific parameters in the zoom lens are described below.

[0164] Table 9 Optical design values ​​of the zoom lens in Example 3

[0165]

[0166] Table 10 Design values ​​of optical physical parameters of a zoom lens

[0167] Surface number Surface type Radius of curvature thickness nd vd Semi-caliber K Value 1 Standard surface 331.002 0.786 1.847 31.200 / -0.040 9.954 0.000 2 Standard surface 69.187 1.900 1.497 90.040 / -0.050 9.815 0.000 3 Standard surface -76.343 0.273 9.755 0.000 4 Standard surface 24.182 2.087 1.520 84.610 / 0.051 9.195 0.000 5 Standard surface 122.659 -6.046 9.052 0.000 6 Standard surface INF STEP1 11.511 0.000 7 Standard surface -46.647 0.520 1.755 46.310 / 0.003 5.458 0.000 8 Standard surface 19.322 1.296 5.256 0.000 9 Standard surface -30.096 2.584 1.593 68.340 / 0.000 5.252 0.000 10 Standard surface 26.226 1.378 2.139 27.560 / 0.000 5.471 0.000 11 Standard surface 389.660 22.256 5.480 0.000 12 Standard surface INF -STEP1 9.236 0.000 13 STO INF -0.522 5.413 0.000 14 Standard surface 11.608 2.952 1.438 94.520 / 0.000 5.658 0.000 15 Standard surface -47.042 1.144 5.658 0.000 16 even aspherical surface 7.816 1.378 1.536 55.980 / 0.000 5.082 0.341 17 even aspherical surface 5.005 0.251 4.701 -1.036 18 Standard surface 6.754 3.052 1.593 68.630 / 0.000 4.544 0.000 19 Standard surface -99.793 0.583 1.654 39.540 / 0.000 4.544 0.000 20 Standard surface 9.912 0.040 4.111 0.000 21 Standard surface INF STEP 2 4.178 0.000 22 Standard surface 12.312 2.691 1.497 42.740 / 0.095 3.966 0.000 23 Standard surface -9.013 0.128 3.966 0.000 24 even aspherical surface -11.596 1.573 1.811 20.940 / -0.018 3.748 0.000 25 even aspherical surface -41.053 0.235 3.793 -46.270 26 even aspherical surface -6.115 0.794 1.640 23.500 / 0.000 3.738 -6.949 27 even aspherical surface 3929.550 0.052 3.786 34.392 28 even aspherical surface 3.488 2.143 1.629 24.640 / 0.000 3.937 -3.613 29 even aspherical surface 5.744 5.013 3.776 0.516 30 Standard surface INF -STEP2 0.000 31 Standard surface INF 0.700 1.517 64.200 / 0.000 0.000 32 Standard surface INF 2.985 0.000 33 Image plane

[0168] In the above Table 10, the surface numbers are numbered according to the order of the surfaces of each lens, "1" represents the object surface of the first lens, and "2" represents the image surface of the first lens. "STO" represents the aperture of the lens; the radius of curvature represents the degree of curvature of the lens surface, and the unit is mm. A positive value represents that the surface is bent toward the object side, and a negative value represents that the surface is bent toward the image side, where "INF" represents that the surface is a plane and the radius of curvature is infinite. Thickness represents the central axial distance from the current surface to the next surface, and the unit is mm. "nd" represents the ability of the material between the current surface and the next surface to deflect light. A blank space represents that the current position is air, and the refractive index is 1. "vd" represents the dispersion characteristics of the material between the current surface and the next surface for light, and a blank space represents that the current position is air. dPgF represents the relative partial dispersion of the material. The semi-aperture represents half of the aperture size of the current surface. The K value represents the numerical value of the cone coefficient of the aspheric surface.

[0169] Table 11 Zoom intervals at the wide-angle and telephoto ends of a zoom lens

[0170] Wide-angle end Telephoto end STEP1 6.964 21.108 STEP 2 2.019 2.082 focal length 12.202 26.180 F / # 1.775 1.771 Field of view 43.62° 19.19°

[0171] The zoom intervals in Table 11 are the different intervals at the wide-angle end and the telephoto end of the lens.

[0172] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0173]

[0174] Wherein, z is the axial sagittal height of the aspheric surface in the Z direction; r is the height of the aspheric surface; c is the curvature of the fitted spherical surface, which is the reciprocal of the curvature radius R; k is the fitted cone coefficient; a4, a6, a8, a10, a12, a14, a16 are the high-order aspheric coefficients of the corresponding aspheric surface of the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order, a i r i The combination becomes the high-order terms corresponding to the aspherical surface.

[0175] Table 12 Design values ​​of aspheric cone coefficients in a zoom lens

[0176]

[0177] "-7.765E-04" means -7.765*10 -4 The remaining coefficients are expressed in this way.

[0178] Further, further, Fig.19 This is a light fan diagram of the zoom lens at the wide-angle end provided by the third embodiment of the present invention, such as Fig.19 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, the vertical axis is the vertical axis aberration, and the light in the figure describes the aberration of the main light of the system. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in this field of view are focused on the same point on the image plane; the vertical axis in a single image can also be expressed as the maximum dispersion range of the light beam on the ideal image plane. It can be seen from the figure that the main wavelength of this zoom lens in each field of view is well close to the horizontal axis, indicating that the monochromatic aberration in each field of view is well corrected.

[0179] Fig. 20 This is a schematic diagram of the axial chromatic aberration of the field curvature of the zoom lens provided in the third embodiment of the present invention at the wide-angle end. In the figure, the vertical direction represents the normalization of the 0 field of view pupil plane, 0 represents the center of the pupil, and the vertical vertex represents the pupil vertex; the horizontal direction is the axial chromatic aberration of different wavelengths (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm), in millimeters (mm). As can be seen in the figure, the axial chromatic aberration of the system is within the range of ±0.05mm, indicating that the system chromatic aberration is well corrected and the infrared confocal characteristics of the system can be well realized.

[0180] Fig.21 This is a diagram of the vertical axis chromatic aberration of the zoom lens at the wide-angle end provided in Example 3 of the present invention. The vertical direction in the diagram represents the field of view angle, 0 represents the field of view angle parallel to the optical axis, and the vertical vertex represents the maximum half field of view angle; the horizontal direction is the offset of the meridian range based on 0.546μm as the reference, in microns (μm). The numbers on the curves in the figure represent the wavelength represented by the curve, in microns (μm). As can be seen from the figure, the vertical axis chromatic aberration of each wavelength of the system (specifically 436nm, 486.1nm, 546nm, 587.6nm and 656.3nm) is within ±10μm, indicating that the system chromatic aberration is well corrected. As the angle increases, the vertical axis chromatic aberrations of each wavelength overlap, indicating that each field of view of the system has a certain degree of chromatic aberration correction.

[0181] Fig. 22 This is a light fan diagram of the zoom lens at the telephoto end provided by the third embodiment of the present invention, such as Fig. 22As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, the vertical axis is the vertical axis aberration, and the light in the figure describes the aberration of the main light of the system. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in this field of view are focused on the same point on the image plane; the vertical axis in a single image can also be expressed as the maximum dispersion range of the light beam on the ideal image plane. It can be seen from the figure that the main wavelength of this zoom lens in each field of view is well close to the horizontal axis, indicating that the monochromatic aberration in each field of view is well corrected.

[0182] Fig.23 This is a schematic diagram of the axial chromatic aberration of the zoom lens at the telephoto end provided in the third embodiment of the present invention. In the figure, the vertical direction represents the normalization of the pupil plane of the 0 field of view, 0 represents the center of the pupil, and the vertical vertex represents the vertex of the pupil; the horizontal direction is the axial chromatic aberration of different wavelengths (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm), in millimeters (mm). As can be seen in the figure, the axial chromatic aberration of the system is within the range of ±0.05mm, indicating that the system chromatic aberration is well corrected and the infrared confocal characteristics of the system can be well realized.

[0183] Fig.24 This is a diagram of the vertical axis chromatic aberration of the zoom lens at the telephoto end provided in Example 3 of the present invention. The vertical direction in the diagram represents the field of view angle, 0 represents the field of view angle parallel to the optical axis, and the vertical vertex represents the maximum half field of view angle; the horizontal direction is the offset of the meridian range based on 0.546μm as the reference, in microns (μm). The numbers on the curves in the figure represent the wavelength represented by the curve, in microns (μm). As can be seen from the figure, the vertical axis chromatic aberration of each wavelength of the system (specifically 436nm, 486.1nm, 546nm, 587.6nm and 656.3nm) is within ±10μm, indicating that the system chromatic aberration is well corrected. As the angle increases, the vertical axis chromatic aberrations of each wavelength overlap, indicating that each field of view of the system has a certain degree of chromatic aberration correction.

[0184] In summary, the zoom lens provided in the third embodiment of the present invention uses a glass-plastic hybrid lens, which meets the requirements of 1 / 1.8" large target surface and high-pixel imaging, and has the characteristics of infrared confocal, constant large aperture, and low cost.

[0185] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A zoom lens, characterized in that: It includes a system front group and a system rear group arranged in sequence from the object plane to the image plane along the optical axis, the system front group has a negative optical power, and the system rear group has a positive optical power; The optical power of the front group of the system at the wide-angle end is The optical power at the telephoto end is The optical power of the rear group of the system at the wide-angle end is The optical power at the telephoto end is in, 2. The zoom lens according to claim 1, wherein: The system front group includes a first fixed lens group and a variable magnification lens group, and the system rear group includes a second fixed lens group and a compensation lens group; The first fixed lens group has positive optical power, the variable power lens group has negative optical power, the second fixed lens group has positive optical power, and the compensation lens group has positive optical power.

3. The zoom lens according to claim 2, wherein: The optical power of the first fixed lens group is The optical power of the variable magnification lens group is The optical power of the second fixed lens group is The optical power of the compensation lens group is The focal length of the zoom lens at the wide-angle end is in, 4. The zoom lens according to claim 3, wherein: The first fixed lens group includes a first lens, a second lens and a third lens arranged in sequence from the object plane to the image plane, the first lens has a negative optical power, the second lens has a positive optical power, and the third lens has a positive optical power; The zoom lens group includes a fourth lens, a fifth lens and a sixth lens, the fourth lens has a negative optical power, the fifth lens has a negative optical power, and the sixth lens has a positive optical power; The second fixed lens group includes a seventh lens, an eighth lens, a ninth lens and a tenth lens, the seventh lens has positive focal power, the ninth lens has positive focal power, and the tenth lens has negative focal power; The compensation lens group includes an eleventh lens, a twelfth lens, a thirteenth lens and a fourteenth lens, the eleventh lens has positive focal power, the thirteenth lens has negative focal power, and the fourteenth lens has positive focal power.

5. The zoom lens according to claim 4, wherein: The optical power of the first lens is The optical power of the second lens is The focal power of the third lens is The optical power of the fourth lens is The optical power of the fifth lens is The optical power of the sixth lens is The optical power of the seventh lens is The optical power of the tenth lens is in, 6. The zoom lens according to claim 4, wherein: The first lens and the second lens are cemented together; the fifth lens and the sixth lens are cemented together; and the ninth lens and the tenth lens are cemented together.

7. The zoom lens according to claim 6, wherein: The Abbe number of the first lens is vd1, the Abbe number of the second lens is vd2, the refractive index of the third lens is nd3, the Abbe number of the third lens is vd3, the refractive index of the fifth lens is nd5, the Abbe number of the fifth lens is vd5, the refractive index of the sixth lens is nd6, the Abbe number of the sixth lens is vd6, the Abbe number of the ninth lens is vd9, and the Abbe number of the tenth lens is vd10; Among them, vd1<28.08, vd2>72.13, nd3<1.751, vd3>72.08; nd5<1.720, nd6>1.700, vd5>61.51, vd6<30.30; vd9>62.00,vd10<40.

00.

8. The zoom lens according to claim 4, wherein: The first lens comprises a first object-side surface close to the object plane and a first image-side surface close to the image plane, the first object-side surface is a convex surface, and the first image-side surface is a concave surface; The second lens comprises a second image-side surface close to the image plane, and the second image-side surface is a convex surface; The third lens comprises a third object-side surface close to the object plane and a third image-side surface close to the image plane, the third object-side surface is a convex surface, and the third image-side surface is a concave surface; The fourth lens comprises a fourth object-side surface close to the object plane and a fourth image-side surface close to the image plane, the fourth object-side surface is a concave surface, and the fourth image-side surface is a concave surface; The fifth lens comprises a fifth object-side surface close to the object plane and a fifth image-side surface close to the image plane, the fifth object-side surface is a concave surface, and the fifth image-side surface is a concave surface; The seventh lens comprises a seventh object-side surface close to the object plane, and the seventh object-side surface is a convex surface; The eighth lens comprises an eighth object-side surface close to the object plane and an eighth image-side surface close to the image plane, the eighth object-side surface is a convex surface, and the eighth image-side surface is a concave surface; The ninth lens comprises a ninth object-side surface close to the object plane and a ninth image-side surface close to the image plane, the ninth object-side surface is a convex surface, and the ninth image-side surface is a convex surface; The tenth lens comprises a tenth image-side surface close to the image plane, and the tenth image-side surface is a concave surface; The eleventh lens comprises an eleventh object-side surface close to the object plane and an eleventh image-side surface close to the image plane, the eleventh object-side surface is a convex surface, and the eleventh image-side surface is a convex surface; The twelfth lens comprises a twelfth object-side surface close to the object plane and a twelfth image-side surface close to the image plane, the twelfth object-side surface is a concave surface, and the twelfth image-side surface is a convex surface; The thirteenth lens comprises a thirteenth object-side surface close to the object plane and a thirteenth image-side surface close to the image plane, the thirteenth object-side surface is a concave surface, and the thirteenth image-side surface is a concave surface; The fourteenth lens includes a fourteenth object-side surface close to the object plane and a fourteenth image-side surface close to the image plane. The fourteenth object-side surface is a convex surface, and the fourteenth image-side surface is a concave surface.

9. The zoom lens according to claim 8, wherein: The center thickness of the thirteenth lens is THIC 13 , the edge thickness of the thirteenth lens is EG 13 , the center thickness of the fourteenth lens is THIC 14 , the edge thickness of the fourteenth lens is EG 14 ; Of which, 0.300 <THIC 13 / EG 13 <1.000, EG 14 / THIC 14 <1.

000.

10. The zoom lens according to claim 1, wherein: The focal length of the zoom lens at the wide-angle end is The optical power at the telephoto end is in, 11. The zoom lens according to claim 1, wherein: The F number of the zoom lens at the wide angle end is F W , the F number at the telephoto end is F T ; Among them, F T / F W <1.

159.

12. The zoom lens according to claim 1, wherein: The F number of the zoom lens at the telephoto end is F T ; Among them, F T >1.

593.

13. The zoom lens according to claim 1, wherein: The field of view of the zoom lens at the telephoto end is ω T ; Among them, ω T ≥15.369°.

14. The zoom lens according to claim 4, wherein: The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the ninth lens, the tenth lens and the eleventh lens are all glass spherical lenses; The eighth lens, the twelfth lens, the thirteenth lens and the fourteenth lens are all plastic aspherical lenses.

15. The zoom lens according to claim 1, wherein: The zoom lens also includes an aperture and a filter; The aperture is arranged in the optical path between the front group of the system and the rear group of the system; The filter is arranged in the optical path between the system rear group and the image plane.

Images