A zoom lens

Abstract

The embodiment of the present invention discloses a zoom lens, comprising a focus lens group, a zoom lens group and a fixed lens group arranged in sequence from the object plane to the image plane along the optical axis; the focal power of the focus lens group is negative, the focal power of the zoom lens group is positive, and the focal power of the fixed lens group is positive; the focus lens group comprises a first lens with a negative focal power, a second lens with a negative focal power and a third lens with a positive focal power; the zoom lens group comprises a fourth lens with a positive focal power, a fifth lens with a positive focal power, a sixth lens with a positive focal power, a seventh lens with a negative focal power, an eighth lens with a positive focal power and a ninth lens with a negative focal power; the fixed lens group comprises a tenth lens with a positive focal power. By adopting the above technical scheme, by reasonably setting the focal power of each lens group, the number of lenses included in each lens group and the focal power of each lens, it is ensured that a zoom lens with a larger aperture and higher image quality can be achieved, which is suitable for more situations.

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] In the security field, zoom lenses have been widely used due to their advantages such as long shooting distance and large shooting angle. With the development of technology, cameras are gradually moving towards miniaturization and refinement, which also puts forward more stringent requirements for mainstream zoom lenses.

[0003] At present, the mainstream chip on the market is still 1 / 2.7", but as the size of cameras gradually decreases, the size of traditional zoom lenses gradually cannot meet the requirements of cameras, and traditional zoom lenses have problems such as small aperture. Therefore, it is necessary to develop a lens with small size and large aperture. Summary of the invention

[0004] The present invention provides a zoom lens, which realizes a zoom lens design that can take into account both small size and large aperture.

[0005] An embodiment of the present invention provides a zoom lens, comprising a focus lens group, a zoom lens group and a fixed lens group arranged in sequence from an object plane to an image plane along an optical axis; the optical focal power of the focus lens group is negative, the optical focal power of the zoom lens group is positive, and the optical focal power of the fixed lens group is positive;

[0006] The focusing lens group includes a first lens with negative optical power, a second lens with negative optical power, and a third lens with positive optical power;

[0007] The zoom lens group includes a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with positive optical power, a seventh lens with negative optical power, an eighth lens with positive optical power and a ninth lens with negative optical power;

[0008] The fixed lens group includes a tenth lens with positive optical power.

[0009] Optionally, the first lens, the fourth lens, the sixth lens and the seventh lens are all glass spherical lenses, and the second lens, the third lens, the fifth lens, the eighth lens, the ninth lens and the tenth lens are all plastic aspherical lenses.

[0010] 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;

[0011] The second lens comprises a second object-side surface close to the object plane and a second image-side surface close to the image plane, the second object-side surface is a concave surface, and the second image-side surface is a concave surface;

[0012] The third lens comprises a third object-side surface close to the object plane, and the third object-side surface is a convex surface;

[0013] The fourth lens comprises a fourth object-side surface close to the object plane, and the fourth object-side surface is a convex surface;

[0014] 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 convex surface, and the fifth image-side surface is a concave surface;

[0015] The sixth lens comprises a sixth object-side surface close to the object plane and a sixth image-side surface close to the image plane, the sixth object-side surface is a convex surface, and the sixth image-side surface is a convex surface;

[0016] The seventh lens comprises a seventh object-side surface close to the object plane, and the seventh object-side surface is a concave surface;

[0017] 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;

[0018] 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 concave surface;

[0019] The tenth lens includes a tenth object-side surface close to the object plane and a tenth image-side surface close to the image plane. The tenth object-side surface is a concave surface, and the tenth image-side surface is a convex surface.

[0020] Optionally, the sixth lens and the seventh lens are bonded together.

[0021] Optional, -2.74≤F1 / FW≤-2.54; 2.61≤F2 / FW≤3.10; 21.0≤F3 / FW≤42.6;

[0022] Among them, F1 represents the focal length of the focus lens group, F2 represents the focal length of the zoom lens group, F3 represents the focal length of the fixed lens group; and FW represents the focal length of the wide-angle end of the zoom lens.

[0023] Optional, 0.551≤S1 / S2≤0.583;

[0024] Among them, S1 represents the distance between the closest position of the focus lens group in the zoom lens to the image plane and the farthest position from the image plane during the movement, and S2 represents the distance between the closest position of the zoom lens group in the zoom lens to the image plane and the farthest position from the image plane during the movement.

[0025] Optional, 1.43≤nd1≤1.85; 4.6≤vd1≤96.0; 1.43≤nd4≤1.59, 68.2≤vd4≤96.5;

[0026] 1.43≤nd6≤1.59; 42.8≤vd6≤96.6; 1.64≤nd7≤1.90; 22.8≤vd7≤31.7;

[0027] Among them, nd1 represents the refractive index of the first lens, and vd1 represents the Abbe number of the first lens; nd4 represents the refractive index of the fourth lens, and vd4 represents the Abbe number of the fourth lens; nd6 represents the refractive index of the sixth lens, and vd6 represents the Abbe number of the sixth lens; nd7 represents the refractive index of the seventh lens, and vd7 represents the Abbe number of the seventh lens.

[0028] Optionally, 0.300<ΦG1 / TTLW<0.351; wherein ΦG1 represents the maximum lens diameter in the focusing lens group, and TTLW represents the total optical length of the zoom lens at the wide-angle end.

[0029] Optionally, 4.9≤FT / FW≤6.0; wherein FT represents the focal length of the zoom lens at the telephoto end, and FW represents the focal length of the zoom lens at the wide-angle end.

[0030] Optionally, the zoom lens further includes an aperture stop, and the aperture stop is arranged in the optical path between the fourth lens and the fifth lens.

[0031] The zoom lens provided by the embodiment of the present invention is provided with a focus lens group with negative optical power, a zoom lens group with positive optical power and a fixed lens group with positive optical power, and the focus lens group is provided with a first lens with negative optical power, a second lens with negative optical power and a third lens with positive optical power, the zoom lens group is provided with a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with positive optical power, a seventh lens with negative optical power, an eighth lens with positive optical power and a ninth lens with negative optical power, and the fixed lens group is provided with a tenth lens with positive optical power. By reasonably setting the optical power of each lens group, the number of lenses included in each lens group and the optical power of each lens, it is ensured that a zoom lens with a larger aperture and higher image quality can be achieved, which is suitable for a wider number of situations.

[0032] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they 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

[0033] 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.

[0034] 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;

[0035] 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;

[0036] Figure 3 A schematic diagram of an axial aberration curve of the zoom lens at the wide-angle end provided in Embodiment 1 of the present invention;

[0037] Figure 4 A light fan diagram of the zoom lens at the wide-angle end provided in the first embodiment of the present invention;

[0038] Figure 5 A vertical axis chromatic aberration diagram of the zoom lens provided in the first embodiment of the present invention at the wide-angle end;

[0039] Figure 6 A schematic diagram of an axial aberration curve of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0040] Figure 7 A light fan diagram of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0041] Figure 8 A vertical axis chromatic aberration diagram of the zoom lens provided in the first embodiment of the present invention at the telephoto end;

[0042] 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;

[0043] Fig.10 A schematic diagram of the structure of a zoom lens at the telephoto end provided by Embodiment 2 of the present invention;

[0044] Fig.11 A schematic diagram of an axial aberration curve of a zoom lens at a wide-angle end provided in Embodiment 2 of the present invention;

[0045] Fig.12A light fan diagram of the zoom lens at the wide-angle end provided in the second embodiment of the present invention;

[0046] Fig.13 A vertical axis chromatic aberration diagram of the zoom lens provided in the second embodiment of the present invention at the wide-angle end;

[0047] Fig.14 A schematic diagram of an axial aberration curve of a zoom lens at a telephoto end provided by Embodiment 2 of the present invention;

[0048] Fig.15 A light fan diagram of the zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0049] Fig.16 A vertical axis chromatic aberration diagram of the zoom lens provided in the second embodiment of the present invention at the telephoto end;

[0050] 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;

[0051] Fig.18 A schematic diagram of the structure of a zoom lens at the telephoto end provided by Embodiment 3 of the present invention;

[0052] Fig.19 A schematic diagram of an axial aberration curve of a zoom lens at a wide-angle end provided in Embodiment 3 of the present invention;

[0053] Fig. 20 A light fan diagram of the zoom lens at the wide-angle end provided in the third embodiment of the present invention;

[0054] Fig.21 A vertical axis chromatic aberration diagram of the zoom lens provided in Embodiment 3 of the present invention at the wide-angle end;

[0055] Fig. 22 A schematic diagram of an axial aberration curve of a zoom lens at a telephoto end provided in Embodiment 3 of the present invention;

[0056] Fig.23 A light fan diagram of the zoom lens at the telephoto end provided by the third embodiment of the present invention;

[0057] Fig.24 This is a diagram of vertical axis chromatic aberration of the zoom lens provided in Embodiment 3 of the present invention at the telephoto end. DETAILED DESCRIPTION

[0058] 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.

[0059] Embodiment 1

[0060] 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 This is a schematic diagram of the structure of the zoom lens at the telephoto end provided by the first embodiment of the present invention, as shown in FIG. Figure 1 and Figure 2 As shown, the zoom lens provided in the first embodiment of the present invention comprises a focus lens group G1, a zoom lens group G2 and a fixed lens group G3 which are arranged in sequence from the object plane to the image plane along the optical axis; the optical focal power of the focus lens group G1 is negative, the optical focal power of the zoom lens group G2 is positive, and the optical focal power of the fixed lens group G3 is positive; the focus lens group G1 comprises a first lens 101 with negative optical focal power, a second lens 102 with negative optical focal power and a third lens 103 with positive optical focal power; the zoom lens group G2 comprises a fourth lens 104 with positive optical focal power, a fifth lens 105 with positive optical focal power, a sixth lens 106 with positive optical focal power, a seventh lens 107 with negative optical focal power, an eighth lens 108 with positive optical focal power and a ninth lens 109 with negative optical focal power; the fixed lens group G3 comprises a tenth lens 110 with positive optical focal power.

[0061] Specifically, in the zoom lens provided in this embodiment, the focus lens group G1, the zoom lens group G2 and the fixed lens group G3 can be arranged in a lens barrel ( Figure 1 The fixed lens group G3 is fixed in the lens barrel, and the focus lens group G1 and the zoom lens group G2 can move back and forth along the optical axis in the lens barrel. Through the joint movement of the focus lens group G1 and the zoom lens group G2, 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 focus position.

[0062] It can be understood that in the process of zooming by moving the focus lens group G1 and the zoom lens group G2, 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 optical focal powers, and also has different lengths or shapes.

[0063] Furthermore, the focal length is equal to the difference between the convergence of the image beam and the convergence of the object beam, and it characterizes the ability of the optical system to deflect light. The larger the absolute value of the focal length, the stronger the ability to bend light, and the smaller the absolute value of the focal length, the weaker the ability to bend light. 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 system formed by multiple lenses (i.e., a lens group). The focal length of the focusing lens group G1 is negative to ensure that the light has a larger aperture before entering the aperture, increasing the aperture of the fixed focus lens. At the same time, the focusing lens group G1 cooperates with the fourth lens 104 in the zoom lens group G2 to ensure that the light passes smoothly through the aperture 111, avoiding the generation of stray light such as reflection at the position of the aperture 111, and can adjust the aberration of the zoom lens to a certain extent, ensuring the aberration balance and high and low temperature performance stability of the zoom lens.

[0064] Furthermore, the first lens 101 and the second lens 102 are negative power lenses, which can effectively deflect incident light at large angles, ensuring that more light enters the optical system, thereby effectively increasing the field of view of the zoom lens and ensuring that the optical system has wide-angle characteristics. The third lens 103 is a negative power lens, so that the third lens 103 can timely correct the large aberrations generated by the first lens 101 and the second lens 102, especially the edge aberrations of the zoom lens, thereby improving the imaging resolution of the optical system.

[0065] In summary, the zoom lens provided by the embodiment of the present invention is provided with a focus lens group with negative optical power, a zoom lens group with positive optical power and a fixed lens group with positive optical power, and the focus lens group is provided with a first lens with negative optical power, a second lens with negative optical power and a third lens with positive optical power, the zoom lens group is provided with a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with positive optical power, a seventh lens with negative optical power, an eighth lens with positive optical power and a ninth lens with negative optical power, and the fixed lens group is provided with a tenth lens with positive optical power. By reasonably setting the optical power of each lens group, the number of lenses included in each lens group and the optical power of each lens, it is ensured that a zoom lens with a larger aperture and a higher image quality can be achieved, which is suitable for a wider number of situations.

[0066] Based on the above embodiments, continue to refer to Figure 1 and Figure 2 As shown, the zoom lens further includes an aperture 111 , which is disposed in the optical path between the fourth lens 104 and the fifth lens 105 .

[0067] Specifically, the propagation direction of the light beam can be adjusted by setting the aperture 111, which is beneficial to improving the imaging quality. In addition, the aperture 111 in the zoom lens can be located in the light path between the fourth lens 104 and the fifth lens 105. The aperture 111 is located in the middle of the zoom lens to ensure that the front and rear apertures of the zoom lens are minimized.

[0068] Based on the above embodiments, continue to refer to Figure 1 and Figure 2 As shown, the zoom lens provided by the embodiment of the present invention may further include a filter 112. The filter 112 is disposed in the light path between the tenth lens 110 and the image plane. The filter 112 may filter out interference light and improve the imaging effect of the zoom lens.

[0069] Based on the above embodiments, continue to refer to Figure 1 and Figure 2 As shown, the zoom lens provided by the embodiment of the present invention may further include flat glass, which is arranged in the light path between the filter 112 and the image plane. The flat glass can protect the photosensitive chip in the imaging sensor, wherein the imaging chip is used to convert the light signal collected by the zoom lens into an electrical signal, thereby ensuring the imaging effect of the zoom lens.

[0070] Based on the above embodiments, the first lens 101, the fourth lens 104, the sixth lens 106 and the seventh lens 107 are all glass spherical lenses, and the second lens 102, the third lens 103, the fifth lens 105, the eighth lens 108, the ninth lens 109 and the tenth lens 110 are all plastic aspherical lenses.

[0071] Specifically, the characteristic of the aspherical 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 aspherical lens has a better curvature radius characteristic and has the advantages of improving distortion aberration and improving astigmatism aberration. After adopting the aspherical lens, the aberration occurring during imaging can be eliminated as much as possible, thereby improving the imaging quality of the lens. In addition, the cost of plastic lenses is much lower than that of glass lenses and they are lightweight. From the cost point of view, the use of plastic aspherical lenses in the zoom lens can reduce costs on the one hand and reduce the weight of the lens on the other hand, so that it can meet the requirements of a wider range of uses. The characteristic of the spherical lens is that it has 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. In addition, the thermal expansion coefficient of the glass lens is small and the stability is good. Therefore, the zoom lens includes a glass spherical lens, which can balance high and low temperatures. When the ambient temperature of the zoom lens changes greatly, it is beneficial to maintain the focal length of the zoom lens stable, for example, to ensure that the zoom lens has stable optical performance at -40℃ to 85℃.

[0072] The zoom lens in the embodiment of the present invention includes at least four glass spherical lenses, and there is at least one plastic aspherical lens in the focus lens group G1, the zoom lens group G2 and the fixed lens group G3 of the zoom lens. Glass and plastic can compensate each other. The combination of glass lenses and plastic lenses in the zoom lens can better balance the resolution of the lens under high and low temperature conditions. At the same time, the use of reasonable glass lens combination can also have a good correction effect on the aberration of the lens; the use of the above materials can ensure that the lens has good resolution in the range of -40 to 80°C. In addition, the use of glass lenses can correct the chromatic aberration of the lens to a large extent. The use of the above glass lens combination can meet the requirements of good resolution in the full band range of 430nm-850nm, expanding the scope of use of the lens.

[0073] Furthermore, the use of glass material for the first lens 101 in the focus lens group G1 can protect the lens to a certain extent and extend the service life of the lens. On the other hand, it can also play a certain role in achromatic aberration, avoiding the chromatic aberration at the rear end of the lens from being too large to be corrected; in addition, the first lens 101, the second lens 102 and the third lens 103 form the focus lens group G1, and in this lens group, the high and low temperature state of the lens group needs to be guaranteed to a certain extent. The use of glass material for the first lens 101 can control the high and low temperature conditions of the focus lens group G1 to a large extent, avoiding serious impact on the entire lens. The use of glass material for the fourth lens 104 in the zoom lens group G2 can correct the chromatic aberration of the light before entering the aperture as much as possible, avoiding greater impact on the rear end; at the same time, the fourth lens 104 is a glass lens, which can ensure the high and low temperature state of the zoom lens group G2 to a certain extent. The sixth lens 106 and the seventh lens 107 in the zoom lens group G2 are made of glass, which can cooperate with the fourth lens 104 to control the high and low temperature conditions of the zoom group. The use of a plastic aspherical lens in the tenth lens 110 can control the high-order aberration of light at the rear end of the lens, further improving the image quality. In addition, the use of an aspherical lens at the rear end of the lens can more finely control the exit angle of light at the lens, thereby improving the matching degree between the lens and the signal receiving device.

[0074] On the basis of the above embodiment, the sixth lens 106 and the seventh lens 107 are bonded together. The bonding of the lenses can effectively eliminate the chromatic aberration of the light just passing through the aperture 111, and prevent the generation of difficult-to-eliminate high-order aberrations at the rear end of the lens, thereby improving the imaging quality of the lens to a certain extent, and further ensuring that the lens forms a clear image in the full band. In addition, after the light passes through the aperture, the use of the bonded lens group can effectively correct the chromatic aberration, and avoid the situation where the chromatic aberration is superimposed at the rear end of the lens, resulting in the need for a large amount of high Abbe number materials to pull back at the rear end, thereby saving costs and improving image quality.

[0075] On the basis of the above embodiments, 1.43≤nd1≤1.85; 4.6≤vd1≤96.0; 1.43≤nd4≤1.59, 68.2≤vd4≤96.5; 1.43≤nd6≤1.59; 42.8≤vd6≤96.6; 1.64≤nd7≤1.90; 22.8≤vd7≤31.7; wherein nd1 represents the refractive index of the first lens, and vd1 represents the Abbe number of the first lens; nd4 represents the refractive index of the fourth lens, and vd4 represents the Abbe number of the fourth lens; nd6 represents the refractive index of the sixth lens, and vd6 represents the Abbe number of the sixth lens; nd7 represents the refractive index of the seventh lens, and vd7 represents the Abbe number of the seventh lens.

[0076] Specifically, the refractive index is the ratio of the speed of light in a vacuum to the speed of light in the medium. It is mainly used to describe the material's ability to refract light. Different materials have different refractive indices. In this way, by matching and setting the refractive indices of each glass lens in the zoom lens, the aberration of the lens can be corrected better. The Abbe number is an index used to indicate the dispersion ability of a transparent medium. The more severe the dispersion of the medium, the smaller the Abbe number; conversely, the milder the dispersion of the medium, the larger the Abbe number. The fourth lens 104 in the zoom lens group G2 uses a glass material with a larger Abbe number to correct the chromatic aberration of the light before entering the aperture 111 as much as possible, avoiding a greater impact on the rear end.

[0077] On the basis of the above embodiment, 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 object-side surface close to the object plane and a second image-side surface close to the image plane, the second object-side surface is concave, and the second image-side surface is concave; the third lens 103 includes a third object-side surface close to the object plane, the third object-side surface is convex; the fourth lens 104 includes a fourth object-side surface close to the object plane, the fourth object-side surface is convex; 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 convex, and the fifth image-side surface is concave; the sixth lens 101 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 convex, and the fifth image-side surface is concave; The lens 06 includes a sixth object-side surface close to the object plane and a sixth image-side surface close to the image plane, the sixth object-side surface is a convex surface, and the sixth image-side surface is a convex surface; the seventh lens 107 includes a seventh object-side surface close to the object plane, and the seventh object-side surface is a concave surface; 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 a convex surface, and the eighth image-side surface is a concave surface; 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 a convex surface, and the ninth image-side surface is a concave surface; the tenth lens 110 includes a tenth object-side surface close to the object plane and a tenth image-side surface close to the image plane, the tenth object-side surface is a concave surface, and the tenth image-side surface is a convex surface.

[0078] Specifically, the first object side surface is a convex surface, and the first image side surface is a concave surface, that is, the object side surface of the first lens 101 is convex toward the object plane, and the image side surface is concave toward the image plane, that is, the first lens 101 is a lens of a convex-concave structure. The second object side surface is a concave surface, and the second image side surface is a concave surface, that is, the object side surface of the second lens 102 is concave toward the object plane, and the image side surface is concave toward the image plane, that is, the second lens 102 is a lens of a double concave structure. The third object side surface is a convex surface, that is, the object side surface of the third lens 103 is convex toward the object plane. The fourth object side surface is a convex surface, that is, the object side surface of the fourth lens 104 is convex toward the object plane. The fifth object side surface is a convex surface, and the fifth image side surface is a concave surface, that is, the object side surface of the fifth lens 105 is convex toward the object plane, and the image side surface is concave toward the image plane, that is, the fifth lens 105 is a lens of a convex-concave structure. The sixth object side surface is a convex surface, and the sixth image side surface is a convex surface, that is, the object side surface of the sixth lens 106 is convex toward the object plane, and the image side surface is convex toward the image plane, that is, the sixth lens 106 is a lens of a double convex structure. The seventh object side surface is a concave surface, that is, the object side surface of the seventh lens 105 is concave toward the object plane. The eighth object 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, and the image side surface is concave toward the image plane, that is, the eighth lens 108 is a lens with a convex-concave structure. The ninth object side surface is a convex surface, and the ninth image side surface is a concave surface, that is, the object side surface of the ninth lens 109 is convex toward the object plane, and the image side surface is concave toward the image plane, that is, the ninth lens 109 is a lens with a convex-concave structure. The tenth object side surface is a concave surface, and the ninth image side surface is a convex surface, that is, the object side surface of the tenth lens 110 is concave toward the object plane, and the image side surface is convex toward the image plane, that is, the tenth lens 110 is a lens with a concave-convex structure. Through the surface design of each of the above lenses, combined with the optical focal length of each lens, the imaging effect of the zoom lens can be further adjusted.

[0079] Furthermore, the design of the convex-concave structure of the first lens 101 is conducive to the collection of light to ensure a larger field angle range of the zoom lens. The concave image side surface of the second lens 102 cooperates with the convex object side surface of the third lens 103, which can shorten the total optical length of the focus lens group G1, thereby shortening the total length of the zoom lens. The concave image side surface of the fifth lens 105 cooperates with the convex object side surface of the sixth lens 106, and the concave image side surface of the eighth lens 108 cooperates with the convex object side surface of the ninth lens 109, which can shorten the total optical length of the zoom lens group G2, thereby shortening the total length of the zoom lens.

[0080] Based on the above embodiment, -2.74≤F1 / FW≤-2.54; 2.61≤F2 / FW≤3.10; 21.0≤F3 / FW≤42.6; where F1 represents the focal length of the focus lens group, F2 represents the focal length of the zoom lens group, and F3 represents the focal length of the fixed lens group; FW represents the focal length of the zoom lens at the wide-angle end. This lens matching method is used to achieve a reasonable matching of optical power, so that light passes through the lens more smoothly, and to a large extent corrects the influence of the lens's high-level aberration on the imaging quality.

[0081] On the basis of the above embodiment, 0.551≤S1 / S2≤0.583; wherein S1 represents the distance between the closest position of the focus lens group in the zoom lens and the farthest position from the image plane during the movement, and S2 represents the distance between the closest position of the zoom lens group in the zoom lens and the farthest position from the image plane during the movement. By controlling the moving distances of the focus lens group G1 and the zoom lens group G2, it is ensured that the moving range of the focus lens group G1 is reduced to the greatest extent, and the lens volume is reduced to a great extent.

[0082] Based on the above embodiment, 0.300<ΦG1 / TTLW<0.351; where ΦG1 represents the maximum lens diameter in the focus lens group, and TTLW represents the total optical length of the zoom lens at the wide-angle end. This range limit can control the size of the lens, making the lens more compact while maximizing the field of view and light intake of the lens to meet the use requirements under more stringent conditions.

[0083] Based on the above embodiment, 4.9≤FT / FW≤6.0; wherein FT represents the focal length of the telephoto end of the zoom lens, and FW represents the focal length of the wide-angle end of the zoom lens. By controlling the focal length ratio between the wide-angle end and the telephoto end of the lens, the zoom range and focal length range of the lens can be controlled to meet the use requirements under more conditions.

[0084] As a feasible implementation, the parameters of each lens in the zoom lens are described below.

[0085] Table 1 Optical design values ​​of the zoom lens in Example 1

[0086]

[0087]

[0088] Table 2 Design values ​​of optical physical parameters of a zoom lens

[0089] Surface number Surface type Radius of curvature thickness Refractive index (nd) Abbe number (vd) 1 Standard surface 25.669 0.706 1.77 45.00 2 Standard surface 7.044 4.671 3 Aspheric -22.384 1.261 1.54 55.71 4 Aspheric 14.050 0.192 5 Aspheric 24.696 2.320 1.66 20.38 6 Aspheric -62.561 Zoom interval 1 7 Standard surface 7.666 2.998 1.43 96.50 8 Standard surface -200.767 1.331 9 STO INF -0.539 10 Aspheric 10.558 1.182 1.54 55.71 11 Aspheric 40.444 0.520 12 Standard surface 20.210 2.599 1.43 96.58 13 Standard surface -7.700 0.468 1.64 31.64 14 Standard surface -50.317 0.066 15 Aspheric -30.391 3.281 1.63 30.00 16 Aspheric -67.090 0.515 17 Aspheric 6.309 0.982 1.54 55.71 18 Aspheric 5.753 Zoom interval 2 19 Aspheric -17.523 0.924 1.63 24.64 20 Aspheric -15.164 2.995 21 Standard surface INF 0.693 1.52 64.2 22 Standard surface INF 1.291 23 IMA INF -

[0090] Table 3 Zoom intervals at the wide-angle and telephoto ends of a zoom lens

[0091] Wide angle Telephoto end Zoom interval 1 21.6945 0.6053 Zoom interval 2 0.8920 17.4459

[0092] In the above Table 2, the surface numbers are numbered according to the order of the surfaces of each lens. "S1" represents the object surface of the first lens, "S2" represents the image surface of the first lens, and so on. "STO" represents the aperture of the lens. The radius of curvature represents the degree of curvature of the lens surface. 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. "INF" represents that the surface is a plane and the radius of curvature is infinite. The thickness represents the central axial distance from the current surface to the next surface. The refractive index 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. The Abbe constant represents the dispersion characteristics of the material between the current surface and the next surface to light. A blank space represents that the current position is air.

[0093] The zoom intervals in Table 3 above are different interval values ​​of the lens at the wide-angle end and the telephoto end.

[0094] Table 4 Design values ​​of aspheric cone coefficients in a zoom lens

[0095]

[0096]

[0097] "-8.212795578E-04" means -8.212795578*10 -4 The remaining coefficients are expressed in this way.

[0098] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0099]

[0100] 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.

[0101] The optical parameters of the optical system of this embodiment are shown in Table 5 below.

[0102] Table 5 Specific parameters for this embodiment

[0103]

[0104] Figure 3 Schematic diagram of the axial aberration curve of the zoom lens at the wide-angle end provided in the first embodiment of the present invention, as shown in FIG. Figure 3 As shown, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in millimeters (mm). Figure 3 It can be seen that the axial aberration of normalized apertures of different wavelengths from 0.3 to 1.0 is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled. In addition, at the pupil position of 0.5-0.9, there is no obvious chromatic aberration between visible light and infrared light, which meets the basic requirements of clear imaging at night and achieves the effect of clear imaging in the full band.

[0105] Figure 4 This is a light fan diagram of the zoom lens provided in the first embodiment of the present invention at the wide-angle end, such as Figure 4 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in the 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. The light fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Figure 4 It can be seen that the zoom lens is close to the horizontal axis at each wavelength (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm) in each field of view, indicating that the vertical axis aberration of each wavelength is well corrected. In addition, the curves of each color are not obviously scattered, indicating that the zoom lens also has good correction for chromatic aberration, ensuring the imaging requirements of the zoom lens for clear images in the full band.

[0106] Figure 5 The vertical axis chromatic aberration diagram of the zoom lens provided in the first embodiment of the present invention at the wide-angle end is shown in FIG. Figure 5 As shown in the figure, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (μm). Figure 5 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide-spectrum applications in the full band.

[0107] Figure 6 This is a schematic diagram of the axial aberration curve of the zoom lens at the telephoto end provided in the first embodiment of the present invention. Figure 6As shown, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in millimeters (mm). Figure 6 It can be seen that the axial aberration of normalized apertures of different wavelengths from 0.3 to 1.0 is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled. In addition, at the pupil position of 0.5-0.9, there is no obvious chromatic aberration between visible light and infrared light, which meets the basic requirements of clear imaging at night and achieves the effect of clear imaging in the full band.

[0108] Figure 7 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 7 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in the 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. The light fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Figure 7 It can be seen that the zoom lens is close to the horizontal axis at each wavelength (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm) in each field of view, indicating that the vertical axis aberration of each wavelength is well corrected. In addition, the curves of each color are not obviously scattered, indicating that the zoom lens also has good correction for chromatic aberration, ensuring the imaging requirements of the zoom lens for clear images in the full band.

[0109] Figure 8 The vertical axis chromatic aberration diagram of the zoom lens provided in the first embodiment of the present invention at the telephoto end is shown in FIG. Figure 8 As shown in the figure, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (μm). Figure 8 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled and can meet the needs of wide spectrum applications in the full band.

[0110] In summary, the zoom lens provided in the first embodiment of the present invention realizes full-band confocality in the 436nm-850nm band under a 1 / 2.7″ target surface, a larger aperture, and higher image quality by reasonably setting the optical power of different lens groups, the number of lenses included in different lens groups, and the optical power of each lens, and at the same time, by setting the glass-plastic form and surface shape of each lens, the ratio between the focal length of each lens group and the focal length of the wide-angle end of the zoom lens, the refractive index of the lens, the Abbe number, the bonding condition and other optical parameters. It is suitable for use in more situations.

[0111] Embodiment 2

[0112] 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 The structure diagram of the zoom lens at the telephoto end provided by the second embodiment of the present invention is as follows: Fig. 9 and Fig.10 As shown, the zoom lens provided in Embodiment 2 of the present invention comprises a focus lens group G1, a zoom lens group G2 and a fixed lens group G3 which are arranged in sequence from the object plane to the image plane along the optical axis; the optical focal power of the focus lens group G1 is negative, the optical focal power of the zoom lens group G2 is positive, and the optical focal power of the fixed lens group G3 is positive; the focus lens group G1 comprises a first lens 101 with negative optical focal power, a second lens 102 with negative optical focal power and a third lens 103 with positive optical focal power; the zoom lens group G2 comprises a fourth lens 104 with positive optical focal power, a fifth lens 105 with positive optical focal power, a sixth lens 106 with positive optical focal power, a seventh lens 107 with negative optical focal power, an eighth lens 108 with positive optical focal power and a ninth lens 109 with negative optical focal power; the fixed lens group G3 comprises a tenth lens 110 with positive optical focal power.

[0113] The configuration of the above-mentioned lens is the same as that in the first embodiment, and will not be described in detail here.

[0114] As another feasible implementation, specific parameters in the zoom lens are described below.

[0115] Table 6 Optical design values ​​of the zoom lens in Example 2

[0116]

[0117]

[0118] Table 7 Design values ​​of optical physical parameters of a zoom lens

[0119] Surface number Surface type Radius of curvature thickness Materials (n.d.) Material (vd) 1 Standard surface 25.474 0.695 1.84 44.6 2 Standard surface 7.499 4.662 3 Aspheric -24.062 1.250 1.54 55.7 4 Aspheric 10.816 0.192 5 Aspheric 15.170 2.313 1.66 20.4 6 Aspheric -129.581 Zoom interval 1 7 Standard surface 8.592 2.979 1.59 68.2 8 Standard surface 673.548 1.120 9 STO INF -0.350 10 Aspheric 25.530 1.184 1.54 55.7 11 Aspheric 39.958 0.507 12 Standard surface 13.936 2.594 1.59 68.5 13 Standard surface -10.451 0.451 1.80 22.8 14 Standard surface -3659.060 0.064 15 Aspheric -59.262 3.276 1.63 24.6 16 Aspheric -56.527 0.503 17 Aspheric 8.952 0.986 1.54 55.7 18 Aspheric 7.671 Zoom interval 2 19 Aspheric -10.581 0.925 1.63 24.6 20 Aspheric -9.493 3.000 21 Standard surface INF 0.700 1.52 64.2 22 Standard surface INF 1.501 23 IMA INF -

[0120] Table 8 Zoom intervals at the wide-angle and telephoto ends of a zoom lens

[0121] Wide angle Telephoto end Zoom interval 1 23.7070 0.0355 Zoom interval 2 0.7570 119.964

[0122] In the above Table 7, the surface numbers are numbered according to the order of the surfaces of each lens. "S1" represents the object surface of the first lens, "S2" represents the image surface of the first lens, and so on. "STO" represents the aperture of the lens. The radius of curvature represents the degree of curvature of the lens surface. 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. "INF" represents that the surface is a plane and the radius of curvature is infinite. The thickness represents the central axial distance from the current surface to the next surface. The refractive index 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. The Abbe constant represents the dispersion characteristics of the material between the current surface and the next surface to light. A blank space represents that the current position is air.

[0123] The zoom intervals in Table 8 above are different interval values ​​for the lens at the wide-angle end and the telephoto end.

[0124] Table 9 Design values ​​of aspheric cone coefficients in a zoom lens

[0125]

[0126]

[0127] "-8.8898582996E-04" means -8.88985829964E*10 -4 The remaining coefficients are expressed in this way.

[0128] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0129]

[0130] 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.

[0131] The optical parameters of the optical system of this embodiment are shown in Table 10 below.

[0132] Table 10 Specific parameters for this embodiment

[0133]

[0134] Fig.11 This is a schematic diagram of the axial aberration curve of the zoom lens at the wide-angle end provided in the second embodiment of the present invention, as shown in FIG. Fig.11 As shown, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in millimeters (mm). Fig.11 It can be seen that the axial aberration of normalized apertures of different wavelengths from 0.3 to 1.0 is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled. In addition, at the pupil position of 0.5-0.9, there is no obvious chromatic aberration between visible light and infrared light, which meets the basic requirements of clear imaging at night and achieves the effect of clear imaging in the full band.

[0135] Fig.12 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.12 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in the 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. The light fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Fig.12 It can be seen that the zoom lens is close to the horizontal axis at each wavelength (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm) in each field of view, indicating that the vertical axis aberration of each wavelength is well corrected. In addition, the curves of each color are not obviously scattered, indicating that the zoom lens also has good correction for chromatic aberration, ensuring the imaging requirements of the zoom lens for clear images in the full band.

[0136] Fig.13 The vertical axis chromatic aberration diagram of the zoom lens provided in the second embodiment of the present invention at the wide-angle end is as follows: Fig.13 As shown in the figure, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (μm). Fig.13 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide-spectrum applications in the full band.

[0137] Fig.14 This is a schematic diagram of the axial aberration curve of the zoom lens at the telephoto end provided by the second embodiment of the present invention, as shown in FIG. Fig.14As shown, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in millimeters (mm). Fig.14 It can be seen that the axial aberration of normalized apertures of different wavelengths from 0.3 to 1.0 is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled. In addition, at the pupil position of 0.5-0.9, there is no obvious chromatic aberration between visible light and infrared light, which meets the basic requirements of clear imaging at night and achieves the effect of clear imaging in the full band.

[0138] Fig.15 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.15 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in the 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. The light fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Fig.15 It can be seen that the zoom lens is close to the horizontal axis at each wavelength (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm) in each field of view, indicating that the vertical axis aberration of each wavelength is well corrected. In addition, the curves of each color are not obviously scattered, indicating that the zoom lens also has good correction for chromatic aberration, ensuring the imaging requirements of the zoom lens for clear images in the full band.

[0139] Fig.16 The vertical axis chromatic aberration diagram of the zoom lens provided in the second embodiment of the present invention at the telephoto end is as follows: Fig.16 As shown in the figure, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (μm). Fig.16 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled and can meet the needs of wide spectrum applications in the full band.

[0140] In summary, the zoom lens provided in the second embodiment of the present invention realizes full-band confocality in the 436nm-850nm band under a 1 / 2.7″ target surface, a larger aperture, and higher image quality by reasonably setting the optical power of different lens groups, the number of lenses included in different lens groups, and the optical power of each lens, and at the same time, by setting the glass-plastic form and surface shape of each lens, the ratio between the focal length of each lens group and the focal length of the wide-angle end of the zoom lens, the refractive index of the lens, the Abbe number, the bonding condition and other optical parameters. It is suitable for use in more situations.

[0141] Embodiment 3

[0142] 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 Embodiment 3 of the present invention comprises a focus lens group G1, a zoom lens group G2 and a fixed lens group G3 which are arranged in sequence from the object plane to the image plane along the optical axis; the optical focal power of the focus lens group G1 is negative, the optical focal power of the zoom lens group G2 is positive, and the optical focal power of the fixed lens group G3 is positive; the focus lens group G1 comprises a first lens 101 with negative optical focal power, a second lens 102 with negative optical focal power and a third lens 103 with positive optical focal power; the zoom lens group G2 comprises a fourth lens 104 with positive optical focal power, a fifth lens 105 with positive optical focal power, a sixth lens 106 with positive optical focal power, a seventh lens 107 with negative optical focal power, an eighth lens 108 with positive optical focal power and a ninth lens 109 with negative optical focal power; the fixed lens group G3 comprises a tenth lens 110 with positive optical focal power.

[0143] The configuration of the above-mentioned lens is the same as that in the first embodiment, and will not be described in detail here.

[0144] As another feasible implementation, specific parameters in the zoom lens are described below.

[0145] Table 11 Optical design values ​​of the zoom lens in Example 3

[0146]

[0147]

[0148] Table 12 Design values ​​of optical physical parameters of a zoom lens

[0149]

[0150]

[0151] Table 13 Zoom intervals at the wide-angle and telephoto ends of a zoom lens

[0152] Wide angle Telephoto end Zoom interval 1 20.7648 0.02 Zoom interval 2 0.9070 17.4040

[0153] In the above Table 12, the surface numbers are numbered according to the order of the surfaces of each lens. "S1" represents the object surface of the first lens, "S2" represents the image surface of the first lens, and so on. "STO" represents the aperture of the lens. The radius of curvature represents the degree of curvature of the lens surface. 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. "INF" represents that the surface is a plane and the radius of curvature is infinite. The thickness represents the central axial distance from the current surface to the next surface. The refractive index 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. The Abbe constant represents the dispersion characteristics of the material between the current surface and the next surface to light. A blank space represents that the current position is air.

[0154] The zoom intervals in Table 13 above are different interval values ​​for the lens at the wide-angle end and the telephoto end.

[0155] Table 14 Design values ​​of aspheric cone coefficients in a zoom lens

[0156]

[0157]

[0158] "-9.2563783044E-04" means -9.2563783044*10 -4 The remaining coefficients are expressed in this way.

[0159] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0160]

[0161] 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.

[0162] The optical parameters of the optical system of this embodiment are shown in Table 15 below.

[0163] Table 15 Specific parameters for this embodiment

[0164]

[0165]

[0166] Fig.19 This is a schematic diagram of the axial aberration curve of the zoom lens at the wide-angle end provided in the third embodiment of the present invention. Fig.19 As shown, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in millimeters (mm). Fig.19 It can be seen that the axial aberration of normalized apertures of different wavelengths from 0.3 to 1.0 is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled. In addition, at the pupil position of 0.5-0.9, there is no obvious chromatic aberration between visible light and infrared light, which meets the basic requirements of clear imaging at night and achieves the effect of clear imaging in the full band.

[0167] Fig. 20 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. 20 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in the 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. The light fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Fig. 20 It can be seen that the zoom lens is close to the horizontal axis at each wavelength (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm) in each field of view, indicating that the vertical axis aberration of each wavelength is well corrected. In addition, the curves of each color are not obviously scattered, indicating that the zoom lens also has good correction for chromatic aberration, ensuring the imaging requirements of the zoom lens for clear images in the full band.

[0168] Fig.21 This is a vertical axis chromatic aberration diagram of the zoom lens provided in the third embodiment of the present invention at the wide-angle end, as shown in FIG. Fig.21 As shown in the figure, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (μm). Fig.21 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled and can meet the needs of wide-spectrum applications in the full band.

[0169] Fig. 22 This is a schematic diagram of the axial aberration curve of the zoom lens at the telephoto end provided by the second embodiment of the present invention, as shown in FIG. Fig. 22 As shown, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in millimeters (mm). Fig. 22 It can be seen that the axial aberration of normalized apertures of different wavelengths from 0.3 to 1.0 is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the wide-angle end is well controlled. In addition, at the pupil position of 0.5-0.9, there is no obvious chromatic aberration between visible light and infrared light, which meets the basic requirements of clear imaging at night and achieves the effect of clear imaging in the full band.

[0170] Fig.23 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.23 As shown in the figure, the horizontal axis in a single figure is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, and all light rays in the 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. The light fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Fig.23 It can be seen that the zoom lens is close to the horizontal axis at each wavelength (specifically 436nm, 486nm, 546nm, 588nm, 656nm and 850nm) in each field of view, indicating that the vertical axis aberration of each wavelength is well corrected. In addition, the curves of each color are not obviously scattered, indicating that the zoom lens also has good correction for chromatic aberration, ensuring the imaging requirements of the zoom lens for clear images in the full band.

[0171] Fig.24 The vertical axis chromatic aberration diagram of the zoom lens provided in the second embodiment of the present invention at the telephoto end is as follows: Fig.24 As shown in the figure, the vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertex in the vertical axis represents the maximum pupil radius; the main wavelength uses 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (μm). Fig.24 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a reasonable range, indicating that the vertical chromatic aberration of the zoom lens at the telephoto end is well controlled and can meet the needs of wide spectrum applications in the full band.

[0172] In summary, the zoom lens provided in the second embodiment of the present invention realizes full-band confocality in the 436nm-850nm band under a 1 / 2.7″ target surface, a larger aperture, and higher image quality by reasonably setting the optical power of different lens groups, the number of lenses included in different lens groups, and the optical power of each lens, and at the same time, by setting the glass-plastic form and surface shape of each lens, the ratio between the focal length of each lens group and the focal length of the wide-angle end of the zoom lens, the refractive index of the lens, the Abbe number, the bonding condition and other optical parameters. It is suitable for use in more situations.

[0173] 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 comprises a focus lens group, a zoom lens group and a fixed lens group which are arranged in sequence from the object plane to the image plane along the optical axis; the optical focal power of the focus lens group is negative, the optical focal power of the zoom lens group is positive, and the optical focal power of the fixed lens group is positive; The focusing lens group includes a first lens with negative optical power, a second lens with negative optical power, and a third lens with positive optical power; The zoom lens group includes a fourth lens with positive optical power, a fifth lens with positive optical power, a sixth lens with positive optical power, a seventh lens with negative optical power, an eighth lens with positive optical power and a ninth lens with negative optical power; The fixed lens group includes a tenth lens with positive optical power.

2. The zoom lens according to claim 1, wherein: The first lens, the fourth lens, the sixth lens and the seventh lens are all glass spherical lenses, and the second lens, the third lens, the fifth lens, the eighth lens, the ninth lens and the tenth lens are all plastic aspherical lenses.

3. The zoom lens according to claim 1, 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 object-side surface close to the object plane and a second image-side surface close to the image plane, the second object-side surface is a concave surface, and the second image-side surface is a concave surface; The third lens comprises a third object-side surface close to the object plane, and the third object-side surface is a convex surface; The fourth lens comprises a fourth object-side surface close to the object plane, and the fourth object-side surface is a convex 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 convex surface, and the fifth image-side surface is a concave surface; The sixth lens comprises a sixth object-side surface close to the object plane and a sixth image-side surface close to the image plane, the sixth object-side surface is a convex surface, and the sixth image-side surface is a convex surface; The seventh lens comprises a seventh object-side surface close to the object plane, and the seventh object-side surface is a concave 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 concave surface, and the eighth image-side surface is a convex 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 concave surface; The tenth lens includes a tenth object-side surface close to the object plane and a tenth image-side surface close to the image plane. The tenth object-side surface is a concave surface, and the tenth image-side surface is a convex surface.

4. The zoom lens according to claim 1, wherein: The sixth lens is glued to the seventh lens.

5. The zoom lens according to claim 1, wherein: -2.74≤F1 / FW≤-2.54; 2.61≤F2 / FW≤3.10; 21.0≤F3 / FW≤42.6; Among them, F1 represents the focal length of the focus lens group, F2 represents the focal length of the zoom lens group, F3 represents the focal length of the fixed lens group; and FW represents the focal length of the wide-angle end of the zoom lens.

6. The zoom lens according to claim 1, wherein: 0.551≤S1 / S2≤0.583; Among them, S1 represents the distance between the closest position of the focus lens group in the zoom lens to the image plane and the farthest position from the image plane during the movement, and S2 represents the distance between the closest position of the zoom lens group in the zoom lens to the image plane and the farthest position from the image plane during the movement.

7. The zoom lens according to claim 1, wherein: 1.43≤nd1≤1.85;4.6≤vd1≤96.0; 1.43≤nd4≤1.59, 68.2≤vd4≤96.5; 1.43≤nd6≤1.59;42.8≤vd6≤96.6; 1.64≤nd7≤1.90; 22.8≤vd7≤31.7; Among them, nd1 represents the refractive index of the first lens, and vd1 represents the Abbe number of the first lens; nd4 represents the refractive index of the fourth lens, and vd4 represents the Abbe number of the fourth lens; nd6 represents the refractive index of the sixth lens, and vd6 represents the Abbe number of the sixth lens; nd7 represents the refractive index of the seventh lens, and vd7 represents the Abbe number of the seventh lens.

8. The zoom lens according to claim 1, wherein: 0.300<ΦG1 / TTLW<0.351; Wherein, ΦG1 represents the maximum lens diameter in the focusing lens group, and TTLW represents the total optical length of the zoom lens at the wide-angle end.

9. The zoom lens according to claim 1, wherein: 4.9≤FT / FW≤6.0; Wherein, FT represents the focal length of the zoom lens at the telephoto end, and FW represents the focal length of the zoom lens at the wide-angle end.

10. The zoom lens according to claim 1, wherein: The zoom lens further includes an aperture stop, which is disposed in the optical path between the fourth lens and the fifth lens.

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