A zoom lens

Abstract

The present invention provides a zoom lens, comprising a first fixed lens group, a variator lens group, an aperture, a second fixed lens group, and a focus lens group, arranged sequentially along the optical axis from the object side to the image side. The first fixed lens group comprises a first lens, a second lens, and a third lens, arranged sequentially along the optical axis from the object side to the image side; the variator lens group comprises a fourth lens, a fifth lens, and a sixth lens, arranged sequentially along the optical axis from the object side to the image side; the second fixed lens group comprises a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, and a thirteenth lens, arranged sequentially along the optical axis from the object side to the image side; and the focus lens group comprises a fourteenth lens, a fifteenth lens, and a sixteenth lens, arranged sequentially along the optical axis from the object side to the image side. The first lens and the second lens form a cemented lens group; and the second fixed lens group comprises at least two cemented lens groups. Embodiments of the present invention achieve a large aperture, minimal distortion, and clear imaging.

Description

Technical Field

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

[0002] ITS (Intelligent Transport System) lenses are specifically designed for image sensors. They typically offer high resolution, low distortion, and high contrast, providing clear, accurate, and high-quality images. Their design carefully considers multiple factors, including optical properties, mechanical structure, and electronic interfaces, enabling them to effectively adapt to diverse and complex environments.

[0003] At present, most of the commonly used ITS lenses on the market are fixed-focus lenses with low image quality and poor tolerance in harsh environments. Faced with more complex usage environments, zoom lenses have gradually become the new favorite in the ITS field. However, the types of zoom lenses used in the ITS field on the market are extremely limited, and they have defects such as low image quality, too small focal length range, and large distortion, which have certain difficulties in practical application. Summary of the Invention

[0004] An embodiment of the present invention provides a zoom lens to achieve large aperture, small distortion and clear imaging.

[0005] An embodiment of the present invention provides a zoom lens, comprising a first fixed lens group, a variator lens group, an aperture stop, a second fixed lens group, and a focus lens group, arranged in sequence along an optical axis from the object side to the image side, wherein the first fixed lens group, the second fixed lens group, and the focus lens group have positive optical power, and the variator lens group has negative optical power;

[0006] The first fixed lens group includes a first lens, a second lens, and a third lens arranged in sequence from the object side to the image side along the optical axis; the variator lens group includes a fourth lens, a fifth lens, and a sixth lens arranged in sequence from the object side to the image side along the optical axis; the second fixed lens group includes a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, and a thirteenth lens arranged in sequence from the object side to the image side along the optical axis; and the focusing lens group includes a fourteenth lens, a fifteenth lens, and a sixteenth lens arranged in sequence from the object side to the image side along the optical axis;

[0007] The first lens and the second lens form a cemented lens group; the second fixed lens group includes at least two cemented lens groups.

[0008] Optionally, the first lens, the fourth lens, the fifth lens, the eighth lens, the tenth lens, the twelfth lens and the fifteenth lens have negative optical power;

[0009] The second lens, the third lens, the sixth lens, the seventh lens, the ninth lens, the eleventh lens, the thirteenth lens, the fourteenth lens, and the sixteenth lens have positive refractive power.

[0010] Optionally, the focal length of the first fixed lens group is FG1, the focal length of the zoom lens group is FG2, the focal length of the second fixed lens group is FG3, the focal length of the focusing lens group is FG4, and the focal length of the zoom lens at the wide-angle end is FW, satisfying:

[0011] 5.14≤FG1 / FW≤5.31;

[0012] -1.77≤FG2 / FW≤-1.66;

[0013] 2.70≤FG3 / FW≤2.89;

[0014] 2.31≤FG4 / FW≤2.76.

[0015] Optionally, the maximum distance that the zoom lens group can move along the optical axis is S2, and the maximum distance that the focus lens group can move along the optical axis is S4, satisfying:

[0016] 24.43≤S2 / S4≤86.99.

[0017] Optionally, at least two of the eighth lens, the ninth lens and the tenth lens form a cemented lens group, and at least two of the eleventh lens, the twelfth lens and the thirteenth lens form a cemented lens group.

[0018] Optionally, the combined focal length of the eighth lens, the ninth lens, and the tenth lens is F8_9_10, the combined focal length of the eleventh lens, the twelfth lens, and the thirteenth lens is F11_12_13, and the focal length of the second fixed lens group is FG3, satisfying:

[0019] -0.69≤F8_9_10 / FG3≤-0.61;

[0020] 0.62≤F11_12_13 / FG3≤0.70.

[0021] Optionally, the refractive index of the seventh lens is nd7, the Abbe number of the seventh lens is vd7, the refractive index of the sixteenth lens is nd16, and the Abbe number of the sixteenth lens is vd16, satisfying:

[0022] 1.804≤nd7≤1.953;

[0023] 32.403≤vd7≤46.513;

[0024] 1.680≤nd16≤1.914;

[0025] 32.322≤vd16≤55.222.

[0026] Optionally, the fourteenth lens and the fifteenth lens form a cemented lens group.

[0027] Optionally, the focal length of the zoom lens at the wide-angle end is FW, and the focal length of the zoom lens at the telephoto end is FT, satisfying:

[0028] 3.052≤FT / FW≤3.333.

[0029] Optionally, the maximum movable distance of the zoom lens group along the optical axis is S2, and the total optical length of the zoom lens is TTL, satisfying:

[0030] 3.795≤TTL / S2≤3.956.

[0031] The zoom lens provided in an embodiment of the present invention is composed of sixteen lenses. The aperture is located between the sixth lens and the seventh lens. By changing the positions of the zoom lens group and the focusing lens group on the optical axis, the zoom lens can be switched between the wide-angle end and the telephoto end. Using a first fixed lens group with positive focal length and a zoom lens group with negative focal length at the front end of the aperture can ensure that a larger light aperture is generated after the light passes through, increase the F number of the zoom lens, and meet the usage requirements under different conditions. In addition, using a cemented lens group in the first fixed lens group can correct the high-order chromatic aberration and aberration of the zoom lens, control the aberration balance of each lens group, ensure that the structure after the light enters the aperture does not produce serious aberrations, and improve the imaging quality of the zoom lens. Using at least two cemented lens groups in the second fixed lens group after the aperture can correct the aberration at the rear end of the zoom lens, and cooperate with the lens group at the front end of the aperture to stabilize the imaging quality of the zoom lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic structural diagram of the zoom lens at the wide-angle end provided in the first embodiment of the present invention;

[0033] Figure 2 A schematic structural diagram of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0034] Figure 3 A vertical chromatic aberration curve diagram of the zoom lens provided in the first embodiment of the present invention at the wide-angle end;

[0035] Figure 4-10 This is a ray fan diagram of the zoom lens provided in the first embodiment of the present invention at the wide-angle end;

[0036] Figure 11This is a graph showing the axial aberration of the zoom lens provided in the first embodiment of the present invention at the wide-angle end;

[0037] Figure 12 A vertical axis chromatic aberration curve diagram of the zoom lens provided in the first embodiment of the present invention at the telephoto end;

[0038] Figures 13-19 A ray fan diagram of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0039] Figure 20 This is a graph showing the axial aberration curve of the zoom lens provided in the first embodiment of the present invention at the telephoto end;

[0040] Figure 21 A schematic structural diagram of the zoom lens at the wide-angle end provided in the second embodiment of the present invention;

[0041] Figure 22 A schematic structural diagram of a zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0042] Figure 23 A vertical chromatic aberration curve diagram of the zoom lens provided in the second embodiment of the present invention at the wide-angle end;

[0043] Figures 24-30 This is a ray fan diagram of the zoom lens provided in the second embodiment of the present invention at the wide-angle end;

[0044] Figure 31 This is a graph showing the axial aberration of the zoom lens at the wide-angle end provided by the second embodiment of the present invention;

[0045] Figure 32 A vertical axis chromatic aberration curve diagram of the zoom lens provided in the second embodiment of the present invention at the telephoto end;

[0046] Figure 33-Figure 39 A ray fan diagram of the zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0047] Figure 40 This is a graph showing the axial aberration curve of the zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0048] Figure 41 A schematic structural diagram of the zoom lens at the wide-angle end provided in the third embodiment of the present invention;

[0049] Figure 42 A schematic diagram of the structure of the zoom lens at the telephoto end provided by the third embodiment of the present invention;

[0050] Figure 43 A vertical chromatic aberration curve of the zoom lens provided in Example 3 of the present invention at the wide-angle end;

[0051] Figures 44-50This is a ray fan diagram of the zoom lens provided in the third embodiment of the present invention at the wide-angle end;

[0052] Figure 51 This is a graph showing the axial aberration curve of the zoom lens at the wide-angle end provided by the third embodiment of the present invention;

[0053] Figure 52 A vertical axis chromatic aberration curve diagram of the zoom lens provided in the third embodiment of the present invention at the telephoto end;

[0054] Figures 53-59 This is a ray fan diagram of the zoom lens at the telephoto end provided by the third embodiment of the present invention;

[0055] Figure 60 This is a graph showing the axial aberration curve of the zoom lens provided in the third embodiment of the present invention at the telephoto end. DETAILED DESCRIPTION

[0056] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0057] Example 1

[0058] Figure 1 This is a schematic structural diagram of the zoom lens at the wide-angle end provided by the first embodiment 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, with reference to Figure 1 and Figure 2 The zoom lens includes a first fixed lens group G1, a variator lens group G2, an aperture STO, a second fixed lens group G3 and a focusing lens group G4, which are arranged in sequence along the optical axis from the object side to the image side. The first fixed lens group G1, the second fixed lens group G3 and the focusing lens group G4 have positive focal power, and the variator lens group G2 has negative focal power.

[0059] The first fixed lens group G1 includes a first lens L1, a second lens L2 and a third lens L3 arranged in sequence along the optical axis from the object side to the image side. The magnification lens group G2 includes a fourth lens L4, a fifth lens L5 and a sixth lens L6 arranged in sequence along the optical axis from the object side to the image side. The second fixed lens group G3 includes a seventh lens L7, an eighth lens L8, a ninth lens L9, a tenth lens L10, an eleventh lens L11, a twelfth lens L12 and a thirteenth lens L13 arranged in sequence along the optical axis from the object side to the image side. The focusing lens group G4 includes a fourteenth lens L14, a fifteenth lens L15 and a sixteenth lens L16 arranged in sequence along the optical axis from the object side to the image side.

[0060] The first lens L1 and the second lens L2 form a cemented lens group; the second fixed lens group G3 includes at least two cemented lens groups.

[0061] The zoom lens provided in an embodiment of the present invention is composed of sixteen lenses. The aperture STO is located between the sixth lens L6 and the seventh lens L7. By changing the position of the zoom lens group G2 and the focus lens group G4 on the optical axis, the zoom lens can be switched between the wide-angle end and the telephoto end. Using a first fixed lens group G1 with positive focal length and a zoom lens group G2 with negative focal length at the front end of the aperture STO can ensure that a larger light aperture is generated after the light passes through, increase the F number of the zoom lens, and meet the usage requirements under different conditions. In addition, using a cemented lens group in the first fixed lens group G1 can correct the high-order chromatic aberration and aberration of the zoom lens, control the aberration balance of each lens group, ensure that the structure after the light enters the aperture STO does not produce serious aberrations, and improve the imaging quality of the zoom lens. Using at least two cemented lens groups in the second fixed lens group G3 after the aperture STO can correct the aberration at the rear end of the zoom lens, and cooperate with the lens group at the front end of the aperture STO to stabilize the imaging quality of the zoom lens. It can achieve the requirements of large aperture, small distortion and clear imaging under the 1 / 1.2″ target surface and in the 436nm~850nm band.

[0062] At least two cemented lens groups are used in the second fixed lens group G3 after the aperture STO. When the light has just passed through the aperture STO, the use of the cemented lens group can correct chromatic aberration well, avoiding the superposition of chromatic aberration at the rear end of the zoom lens, which results in the need for a large amount of high Abbe number material to pull back at the rear end, thereby saving costs and improving image quality.

[0063] Furthermore, the same aperture diameter controls the three ends of the zoom lens (wide-angle, telephoto, and mid-focus). This reduces the aperture range structurally, ensuring a longer travel distance for the zoom lens's movable group, enabling higher imaging magnification or reducing size to meet the demands of various conditions. The movable group is the movable lens group, comprising the zoom lens group G2 and the focus lens group G4.

[0064] Exemplarily, the zoom lens is composed of sixteen glass spherical lenses, and the first lens L1 to the sixteenth lens L16 are glass spherical lenses.

[0065] For example, the cemented lens group used in zoom lens group G2 can correct high-order chromatic aberrations and aberrations of the zoom lens. The fifth lens L5 and the sixth lens L6 form a cemented lens group. In other embodiments, the fifth lens L5 and the sixth lens L6 can be used separately and do not form a cemented lens group.

[0066] Optionally, refer to Figure 1The first lens L1, the fourth lens L4, the fifth lens L5, the eighth lens L8, the tenth lens L10, the twelfth lens L12, and the fifteenth lens L15 have negative refractive power. The second lens L2, the third lens L3, the sixth lens L6, the seventh lens L7, the ninth lens L9, the eleventh lens L11, the thirteenth lens L13, the fourteenth lens L14, and the sixteenth lens L16 have positive refractive power.

[0067] For example, in the first fixed lens group G1, the first lens L1 is a convex-concave lens, the second lens L2 is a convex-convex lens, and the third lens L3 is a convex-concave lens. In the zoom lens group G2, the fourth lens L4 is a concave-concave lens, the fifth lens L5 is a concave-concave lens, and the sixth lens L6 is a convex-concave lens. In the second fixed lens group G3, the seventh lens L7 is a convex-convex lens, the eighth lens L8 is a concave-concave lens, the ninth lens L9 is a convex-convex lens, the tenth lens L10 is a concave-concave lens, the eleventh lens L11 is a convex-convex lens, the twelfth lens L12 is either a concave-concave lens or a concave-convex lens, and the thirteenth lens L13 is either a convex-convex lens or a concave-convex lens. In the focusing lens group G4, the fourteenth lens L14 is a convex-convex lens, the fifteenth lens L15 is a concave-concave lens, and the sixteenth lens L16 is a convex-concave lens. The object-side surface of a convex-concave lens is convex toward the object, while the image-side surface of a convex-concave lens is concave toward the image. A convex-convex lens is a biconvex lens. A concave-concave lens is a biconcave lens. The object-side surface of a concave-convex lens is concave toward the object, while the image-side surface of a concave-convex lens is convex toward the image.

[0068] For example, the position of the diaphragm STO of the zoom lens at different focal lengths remains consistent relative to the image plane, and the diaphragm diameter is the same at different focal lengths, while satisfying: FNO≤1.67; where FNO is the aperture number of the zoom lens at the full focal length (a zoom lens at the full focal length can simultaneously adapt to three different focal lengths: wide angle, medium focal length, and telephoto focal length).

[0069] Illustratively, 1.648≤FNO≤1.667.

[0070] Optionally, refer to Figure 1 The focal length of the first fixed lens group G1 is FG1, the focal length of the zoom lens group G2 is FG2, the focal length of the second fixed lens group G3 is FG3, the focal length of the focus lens group G4 is FG4, and the focal length of the zoom lens at the wide-angle end is FW, satisfying the following: 5.14≤FG1 / FW≤5.31; -1.77≤FG2 / FW≤-1.66;

[0071] 2.70≤FG3 / FW≤2.89; 2.31≤FG4 / FW≤2.76. By properly matching the focal lengths of the first fixed lens group G1, the zoom lens group G2, the second fixed lens group G3, and the focusing lens group G4, light passes through the zoom lens more smoothly, significantly correcting the effects of higher-order aberrations on image quality.

[0072] Optionally, refer to Figure 1 The maximum distance that variator lens group G2 can move along the optical axis is S2, and the maximum distance that focus lens group G4 can move along the optical axis is S4, satisfying the following: 24.43 ≤ S2 / S4 ≤ 86.99. By controlling the movement distances of focus lens group G4 and variator lens group G2, the size and range of motion of focus lens group G4 are minimized, significantly reducing the size of the zoom lens.

[0073] Optionally, refer to Figure 1 At least two of the eighth lens L8, the ninth lens L9, and the tenth lens L10 form a cemented lens group, and at least two of the eleventh lens L11, the twelfth lens L12, and the thirteenth lens L13 form a cemented lens group. The eighth lens L8, the ninth lens L9, and the tenth lens L10 can be combined into a cemented lens group or used as a singlet lens and a doublet lens; the eleventh lens L11, the twelfth lens L12, and the thirteenth lens L13 can be combined into a cemented lens group or used as a singlet lens and a doublet lens.

[0074] Optionally, refer to Figure 1 The combined focal length of the eighth lens L8, the ninth lens L9, and the tenth lens L10 is F8_9_10, the combined focal length of the eleventh lens L11, the twelfth lens L12, and the thirteenth lens L13 is F11_12_13, and the focal length of the second fixed lens group G3 is FG3, satisfying the following conditions: -0.69 ≤ F8_9_10 / FG3 ≤ -0.61; 0.62 ≤ F11_12_13 / FG3 ≤ 0.70. Zoom lenses constructed using all-glass spherical lenses are less capable of correcting higher-order aberrations than those incorporating aspherical lenses. Therefore, the embodiment of the present invention employs two cemented triplet lens groups after the aperture stop STO to effectively correct chromatic aberration and higher-order aberrations generated by the front lens group, thereby improving the imaging quality of the zoom lens. Furthermore, the properties of glass lenses are insensitive to temperature. Zoom lenses constructed using all-glass lenses exhibit more consistent performance across different temperatures, offering stable high and low-temperature performance and improving the environmental adaptability of the zoom lens. The material of the glass spherical lens can be various types of glass known to those skilled in the art, and will not be further described in the embodiment of the present invention.

[0075] Optionally, refer to Figure 1The refractive index and Abbe number of the seventh lens element L7 are nd7 and vd7, respectively. The refractive index and Abbe number of the sixteenth lens element L16 are nd16 and vd16, respectively, satisfying the following conditions: 1.804 ≤ nd7 ≤ 1.953; 32.403 ≤ vd7 ≤ 46.513; 1.680 ≤ nd16 ≤ 1.914; and 32.322 ≤ vd16 ≤ 55.222. Correction of chromatic aberration and higher-order aberrations in a zoom lens primarily depends on the second fixed lens group G3 and the focusing lens group G4. Therefore, the material selection for the seventh lens element L7, the first lens element in the second fixed lens group G3, and the sixteenth lens element L16, the last lens element in the focusing lens group G4, is crucial. By properly selecting the refractive indices of the seventh lens element L7 and the sixteenth lens element L16, the aberrations of each lens group can be controlled to a certain extent, ensuring smooth emission of light from the front end, ensuring resolution and image height, and improving the imaging quality of the zoom lens while maintaining illumination.

[0076] Optionally, refer to Figure 1 The fourteenth lens L14 and the fifteenth lens L15 form a cemented lens group. The cemented lens group in the focus lens group G4 corrects aberrations at the rear end of the zoom lens. During zooming, focus lens group G4 is responsible for focusing the zoom lens as its focal length changes. Using a cemented lens group corrects chromatic aberration and higher-order aberrations generated within focus lens group G4, significantly reducing the aberration burden on other groups of the zoom lens at different focal lengths. This allows the zoom lens to maintain focus throughout its entire focal range while maintaining good image quality, meeting normal usage requirements.

[0077] Optionally, refer to Figure 1 The focal length at the wide-angle end of a zoom lens is FW, and the focal length at the telephoto end is FT, satisfying the following: 3.052 ≤ FT / FW ≤ 3.333. By controlling the focal length ratio between the wide-angle and telephoto ends of a zoom lens, distortion can be kept within a reasonably small range while maintaining a large zoom range and a large image area, meeting the requirements for minimal distortion for zoom lenses.

[0078] Optionally, refer to Figure 1 The maximum distance that variator lens group G2 can move along the optical axis is S2, and the total optical length of the zoom lens is TTL, satisfying the following: 3.795 ≤ TTL / S2 ≤ 3.956. This limitation on the total optical length of variator lens group G2 and the zoom lens compresses the lens space, ensuring that the zoom lens meets the required imaging quality and zoom range while maintaining a compact size.

[0079] For example, refer to Figure 1 and Figure 2The zoom lens may also include a flat glass plate CG. The flat glass plate CG is located on the side of the sixteenth lens L16 away from the first lens L1 and on the side of the sixteenth lens L16 closer to the image plane to protect the photosensitive chip in the imaging sensor. The photosensitive chip is used to convert the light signals collected by the zoom lens into electrical signals, thereby ensuring the imaging effect of the zoom lens.

[0080] In the zoom lens, the first fixed lens group G1, the variable magnification lens group G2, the second fixed lens group G3 and the focus lens group G4 can be set in one lens barrel ( Figure 1 and Figure 2 The first fixed lens group G1 and the second fixed lens group G3 are fixed in the lens barrel, while the variator lens group G2 and the focus lens group G4 can reciprocate along the optical axis within the lens barrel. Through the combined movement of the variator lens group G2 and the focus lens group G4, the focal length of the zoom lens can be continuously changed from short focus to long focus, ensuring high image quality at all focal positions.

[0081] It can be understood that in the process of zooming by moving the zoom lens group G2 and the focus lens group G4, when the focal length is shortest, the zoom lens is at the wide-angle end, and when the focal length is longest, the zoom lens is at the telephoto end. At the wide-angle end and the telephoto end, the zoom lens has different focal lengths and optical focal powers, and also has different shapes.

[0082] Table 1: Design values of the zoom lens in Example 1

[0083]

[0084] Table 1 shows a design value of the zoom lens in Example 1. The specific value can be adjusted according to product requirements and is not a limitation of the embodiment of the present invention. The zoom lens shown in Table 1 can be Figure 1 and Figure 2As shown in . A lens generally consists of two surfaces, each of which is a refractive surface. The surface numbers in Table 1 are numbered according to the surface of each lens. Surface number 1 represents the front surface (i.e., object side) of the first lens L1, surface number 2 represents the back surface (i.e., image side) of the first lens L1, and so on. The radius of curvature represents the degree of curvature of the lens surface. A positive radius of curvature indicates that the center of curvature is on the side of the surface closest to the image plane IMA, meaning that the surface is curved toward the image plane IMA; a negative radius of curvature indicates that the center of curvature is on the side of the surface away from the image plane IMA, meaning that the surface is curved toward the object plane. "Infinity" in the Radius of Curvature column indicates that the surface is flat and has an infinite radius of curvature. The value in the Thickness column represents the axial distance from the current surface to the center of the next surface. The value in the Refractive Index column represents the refractive index of the medium between the current and next surfaces, representing the light-bending ability of the material between the current and next surfaces. The blank space in the Refractive Index column represents the refractive index of air, which is 1. The Abbe number represents the dispersion characteristics of light from the material between the current surface and the next surface, and the blank space indicates that the current position is air.

[0085] Table 2 Zoom interval design values of the zoom lens in Example 1

[0086]

[0087] For example, in Example 1, the maximum diameter of the image plane of the zoom lens at the wide-angle end is 13.1 mm, and the maximum diameter of the image plane at the telephoto end is 13.1 mm. The focal length (FW) of the zoom lens at the wide-angle end is 15.00 mm, and the focal length (FT) of the zoom lens at the telephoto end is 50.00 mm. The zoom lens is applicable to the wavelength range of 436 nm to 850 nm at both the wide-angle end and the telephoto end. The total optical length (TTL) of the zoom lens at both the wide-angle end and the telephoto end is 124 mm.

[0088] For example, in Example 1, the zoom lens has an FNO of 1.648 at the wide-angle end and an FNO of 1.652 at the telephoto end. FG1 / FW=5.31, FG2 / FW=-1.66, FG3 / FW=2.70, FG4 / FW=2.31, S2 / S4=86.99, F8_9_10 / FG3=-0.69, F11_12_13 / FG3=0.70, FT / FW=3.33, and TTL / S2=3.956.

[0089] Figure 3 This is a vertical axis chromatic aberration curve of the zoom lens provided in Example 1 of the present invention at the wide-angle end, with reference to Figure 3, the vertical direction represents the field of view, 0 represents the optical axis, and the vertex of the vertical axis represents the maximum field of view; the main wavelength is 546.07nm, and the horizontal direction represents the offset relative to the main wavelength, in micrometers (um). Figure 3 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a small range, indicating that the vertical chromatic aberration of this zoom lens at the wide-angle end is well controlled and can meet the application requirements under normal conditions.

[0090] Figure 4-10 This is a ray fan diagram of the zoom lens provided in the first embodiment of the present invention at the wide-angle end, referring to Figure 4-10 The ray fan diagram is one of the evaluation methods commonly used by optical designers. The horizontal axis is the normalized beam diameter, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis. At this time, all light rays in the field of view are focused on the same point on the image plane; the vertical axis can also be expressed as the maximum diffusion range of the light beam on the ideal image plane. The ray fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Figure 4-10 As can be seen, at the wide-angle end, the curves for each wavelength at each field of view of this zoom lens are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, there is no noticeable dispersion in the curves for each color, indicating that this zoom lens also effectively corrects chromatic aberration, meeting the requirements of its use.

[0091] Figure 11 This is a graph showing the axial aberration of the zoom lens at the wide-angle end provided in the first embodiment of the present invention. Figure 11 , the vertical direction represents the normalized aperture, 0 represents the optical axis, the vertical axis vertex represents the maximum pupil radius; the main wavelength uses 546.07nm, and the horizontal direction represents the offset relative to the main wavelength, in millimeters (mm). Figure 11 It can be seen that the axial aberrations at different wavelengths and normalized apertures of 0.3 to 1.0 are all controlled within a reasonable range, indicating that the axial aberrations of this zoom lens at the wide-angle end are well controlled and meet usage requirements.

[0092] Figure 12 This is a vertical axis chromatic aberration curve of the zoom lens provided in Example 1 of the present invention at the telephoto end, with reference to Figure 12 The vertical chromatic aberration of the zoom lens at the telephoto end is well controlled and can meet the application requirements under normal conditions.

[0093] Figures 13-19 This is a ray fan diagram of the zoom lens at the telephoto end provided by the first embodiment of the present invention, referring to Figures 13-19At the telephoto end, the curves for each wavelength in each field of view of this zoom lens are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, there is no noticeable dispersion in the curves for each color, indicating that this zoom lens also has good correction for chromatic aberration, meeting the requirements of this zoom lens.

[0094] Figure 20 This is a graph showing the axial aberration of the zoom lens at the telephoto end provided in the first embodiment of the present invention. Figure 20 The axial aberrations of the normalized aperture at different wavelengths of 0.3 to 1.0 are all controlled within a reasonable range, indicating that the axial aberrations of the zoom lens at the telephoto end are well controlled and meet the usage requirements.

[0095] Example 2

[0096] Similarities with the above embodiment are not repeated here.

[0097] Table 3: Design values of the zoom lens in Example 2

[0098]

[0099] Table 3 shows a design value of the zoom lens in Example 2. The specific value can be adjusted according to product requirements and is not a limitation of the embodiment of the present invention. The zoom lens shown in Table 3 can be Figure 21 and Figure 22 As shown in . Example 2 Based on Example 1, part of the cemented lens group is split, and Table 3 has more surfaces than Table 1.

[0100] Table 4 Zoom interval design values of the zoom lens in Example 2

[0101]

[0102] For example, in Example 2, the maximum diameter of the image plane of the zoom lens at the wide-angle end is 13.1 mm, and the maximum diameter of the image plane at the telephoto end is 13.1 mm. The focal length (FW) of the zoom lens at the wide-angle end is 15.1 mm, and the focal length (FT) at the telephoto end is 50.00 mm. The zoom lens is applicable to the wavelength range of 436 nm to 850 nm at both the wide-angle end and the telephoto end. The total optical length (TTL) of the zoom lens at both the wide-angle end and the telephoto end is 124 mm.

[0103] For example, in Example 2, the zoom lens has an FNO of 1.651 at the wide-angle end and an FNO of 1.649 at the telephoto end. FG1 / FW=5.14, FG2 / FW=-1.74, FG3 / FW=2.89, FG4 / FW=2.76, S2 / S4=29.32, F8_9_10 / FG3=-0.61, F11_12_13 / FG3=0.62, FT / FW=3.311, and TTL / S2=3.795.

[0104] Figure 23 This is a vertical axis chromatic aberration curve of the zoom lens provided in Example 2 of the present invention at the wide-angle end, referring to Figure 23 , the vertical direction represents the field of view, 0 represents the optical axis, and the vertex of the vertical axis represents the maximum field of view; the main wavelength is 546.07nm, and the horizontal direction represents the offset relative to the main wavelength, in micrometers (um). Figure 23 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a small range, indicating that the vertical chromatic aberration of this zoom lens at the wide-angle end is well controlled and can meet the application requirements under normal conditions.

[0105] Figures 24-30 This is a ray fan diagram of the zoom lens at the wide-angle end provided by the second embodiment of the present invention, referring to Figures 24-30 The ray fan diagram is one of the evaluation methods commonly used by optical designers. The horizontal axis is the normalized beam diameter, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis. At this time, all light rays in the field of view are focused on the same point on the image plane; the vertical axis can also be expressed as the maximum diffusion range of the light beam on the ideal image plane. The ray fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Figures 24-30 As can be seen, at the wide-angle end, the curves for each wavelength at each field of view of this zoom lens are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, there is no noticeable dispersion in the curves for each color, indicating that this zoom lens also effectively corrects chromatic aberration, meeting the requirements of its use.

[0106] Figure 31 This is an axial aberration curve diagram of the zoom lens at the wide-angle end provided in Example 2 of the present invention, with reference to Figure 31 , the vertical direction represents the normalized aperture, 0 represents the optical axis, the vertical axis vertex represents the maximum pupil radius; the main wavelength uses 546.07nm, and the horizontal direction represents the offset relative to the main wavelength, in millimeters (mm). Figure 31 It can be seen that the axial aberrations at different wavelengths and normalized apertures of 0.3 to 1.0 are all controlled within a reasonable range, indicating that the axial aberrations of this zoom lens at the wide-angle end are well controlled and meet usage requirements.

[0107] Figure 32 This is a vertical axis chromatic aberration curve of the zoom lens provided in the second embodiment of the present invention at the telephoto end, referring to Figure 32 The vertical chromatic aberration of the zoom lens at the telephoto end is well controlled and can meet the application requirements under normal conditions.

[0108] Figure 33-Figure 39 This is a ray fan diagram of the zoom lens at the telephoto end provided by the second embodiment of the present invention, referring to Figure 33-Figure 39 At the telephoto end, the curves for each wavelength in each field of view of this zoom lens are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, there is no noticeable dispersion in the curves for each color, indicating that this zoom lens also has good correction for chromatic aberration, meeting the requirements of this zoom lens.

[0109] Figure 40 This is a graph showing the axial aberration of the zoom lens at the telephoto end provided by the second embodiment of the present invention. Figure 40 The axial aberrations of the normalized aperture at different wavelengths of 0.3 to 1.0 are all controlled within a reasonable range, indicating that the axial aberrations of the zoom lens at the telephoto end are well controlled and meet the usage requirements.

[0110] Example 3

[0111] Similarities with the above embodiment are not repeated here.

[0112] Table 5: Design values of the zoom lens in Example 3

[0113]

[0114] Table 5 shows a design value of the zoom lens in Example 3. The specific value can be adjusted according to product requirements and is not a limitation of the embodiment of the present invention. The zoom lens shown in Table 5 can be Figure 41 and Figure 42 As shown in .

[0115] Table 6 Zoom interval design values of the zoom lens in Example 3

[0116]

[0117] For example, in Example 3, the maximum diameter of the image plane of the zoom lens at the wide-angle end is 13.1 mm, and the maximum diameter of the image plane at the telephoto end is 13.1 mm. The focal length (FW) of the zoom lens at the wide-angle end is 15.21 mm, and the focal length (FT) at the telephoto end is 49.99 mm. The zoom lens is applicable to the wavelength range of 436 nm to 850 nm at the wide-angle end and the telephoto end. The total optical length (TTL) of the zoom lens at the wide-angle end and the telephoto end is 124 mm.

[0118] For example, in Example 3, the zoom lens has an FNO of 1.667 at the wide-angle end and an FNO of 1.652 at the telephoto end. FG1 / FW=5.23, FG2 / FW=-1.77, FG3 / FW=2.88, FG4 / FW=2.64, S2 / S4=38.59, F8_9_10 / FG3=-0.65, F11_12_13 / FG3=0.64, FT / FW=3.052, and TTL / S2=3.832.

[0119] Figure 43 This is a vertical axis chromatic aberration curve of the zoom lens provided in Example 3 of the present invention at the wide-angle end, referring to Figure 43 , the vertical direction represents the field of view, 0 represents the optical axis, and the vertex of the vertical axis represents the maximum field of view; the main wavelength is 546.07nm, and the horizontal direction represents the offset relative to the main wavelength, in micrometers (um). Figure 43 It can be seen that the vertical chromatic aberration of different wavelengths is controlled within a small range, indicating that the vertical chromatic aberration of this zoom lens at the wide-angle end is well controlled and can meet the application requirements under normal conditions.

[0120] Figures 44-50 This is a ray fan diagram of the zoom lens at the wide-angle end provided by the third embodiment of the present invention, referring to Figures 44-50 The ray fan diagram is one of the evaluation methods commonly used by optical designers. The horizontal axis is the normalized beam diameter, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis. At this time, all light rays in the field of view are focused on the same point on the image plane; the vertical axis can also be expressed as the maximum diffusion range of the light beam on the ideal image plane. The ray fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also indicate the size of the vertical axis chromatic aberration. Figures 44-50 As can be seen, at the wide-angle end, the curves for each wavelength at each field of view of this zoom lens are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, there is no noticeable dispersion in the curves for each color, indicating that this zoom lens also effectively corrects chromatic aberration, meeting the requirements of its use.

[0121] Figure 51 This is an axial aberration curve diagram of the zoom lens at the wide-angle end provided in Example 3 of the present invention, with reference to Figure 51 , the vertical direction represents the normalized aperture, 0 represents the optical axis, the vertical axis vertex represents the maximum pupil radius; the main wavelength uses 546.07nm, and the horizontal direction represents the offset relative to the main wavelength, in millimeters (mm). Figure 51 It can be seen that the axial aberrations at different wavelengths and normalized apertures of 0.3 to 1.0 are all controlled within a reasonable range, indicating that the axial aberrations of this zoom lens at the wide-angle end are well controlled and meet usage requirements.

[0122] Figure 52 This is a vertical axis chromatic aberration curve of the zoom lens provided in the third embodiment of the present invention at the telephoto end, referring to Figure 52 The vertical chromatic aberration of the zoom lens at the telephoto end is well controlled and can meet the application requirements under normal conditions.

[0123] Figures 53-59 This is a ray fan diagram of the zoom lens at the telephoto end provided by the third embodiment of the present invention, referring to Figures 53-59 At the telephoto end, the curves for each wavelength in each field of view of this zoom lens are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, there is no noticeable dispersion in the curves for each color, indicating that this zoom lens also has good correction for chromatic aberration, meeting the requirements of this zoom lens.

[0124] Figure 60 This is a graph showing the axial aberration of the zoom lens at the telephoto end provided by the third embodiment of the present invention. Figure 60 The axial aberrations of the normalized aperture at different wavelengths of 0.3 to 1.0 are all controlled within a reasonable range, indicating that the axial aberrations of the zoom lens at the telephoto end are well controlled and meet the usage requirements.

[0125] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations, and substitutions are possible for those skilled in the art without departing from the scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A zoom lens, characterized in that: The optical system comprises a first fixed lens group, a variator lens group, an aperture, a second fixed lens group, and a focus lens group, which are arranged in sequence from the object side to the image side along the optical axis. The first fixed lens group, the second fixed lens group, and the focus lens group have positive optical power, and the variator lens group has negative optical power. The first fixed lens group consists of a first lens, a second lens, and a third lens arranged in sequence from the object side to the image side along the optical axis; the variator lens group consists of a fourth lens, a fifth lens, and a sixth lens arranged in sequence from the object side to the image side along the optical axis; the second fixed lens group consists of a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, and a thirteenth lens arranged in sequence from the object side to the image side along the optical axis; and the focusing lens group consists of a fourteenth lens, a fifteenth lens, and a sixteenth lens arranged in sequence from the object side to the image side along the optical axis; The first lens and the second lens form a cemented lens group; The second fixed lens group includes at least two cemented lens groups; The first lens, the fourth lens, the fifth lens, the eighth lens, the tenth lens, the twelfth lens and the fifteenth lens have negative optical power; The second lens, the third lens, the sixth lens, the seventh lens, the ninth lens, the eleventh lens, the thirteenth lens, the fourteenth lens and the sixteenth lens have positive refractive power; The focal length of the zoom lens group is FG2, the focal length of the zoom lens at the wide-angle end is FW, ； The first lens is a convex-concave lens, the second lens is a convex-convex lens, and the third lens is a convex-concave lens; the fourth lens is a concave-concave lens, the fifth lens is a concave-concave lens, and the sixth lens is a convex-concave lens; The seventh lens is a convex-convex lens, the eighth lens is a concave-concave lens, the ninth lens is a convex-convex lens, the tenth lens is a concave-concave lens, the eleventh lens is a convex-convex lens, the twelfth lens is a concave-concave lens or a concave-convex lens, and the thirteenth lens is a convex-convex lens or a concave-convex lens; The fourteenth lens is a convex-convex lens, the fifteenth lens is a concave-concave lens, and the sixteenth lens is a convex-concave lens.

2. The zoom lens according to claim 1, wherein: The focal length of the first fixed lens group is FG1, the focal length of the second fixed lens group is FG3, and the focal length of the focusing lens group is FG4, satisfying: ； ； 。 3. The zoom lens according to claim 1, wherein: The maximum distance that the zoom lens group can move along the optical axis is S2, and the maximum distance that the focus lens group can move along the optical axis is S4, satisfying: 。 4. The zoom lens according to claim 1, wherein: At least two of the eighth lens, the ninth lens, and the tenth lens form a cemented lens group, and at least two of the eleventh lens, the twelfth lens, and the thirteenth lens form a cemented lens group.

5. The zoom lens according to claim 4, wherein: The combined focal length of the eighth lens, the ninth lens, and the tenth lens is F8_9_10, the combined focal length of the eleventh lens, the twelfth lens, and the thirteenth lens is F11_12_13, and the focal length of the second fixed lens group is FG3, satisfying: ； 。 6. The zoom lens according to claim 1, wherein: The refractive index of the seventh lens is nd7, the Abbe number of the seventh lens is vd7, the refractive index of the sixteenth lens is nd16, and the Abbe number of the sixteenth lens is vd16, satisfying: ； ； ； 。 7. The zoom lens according to claim 1, wherein: The fourteenth lens and the fifteenth lens form a cemented lens group.

8. The zoom lens according to claim 1, wherein: The focal length of the telephoto end of the zoom lens is FT, which satisfies: 。 9. The zoom lens according to claim 1, wherein: The maximum distance that the zoom lens group can move along the optical axis is S2, and the total optical length of the zoom lens is TTL, which satisfies: 。

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