Zoom lens

Abstract

The invention provides a zoom lens. The zoom lens comprises a first fixed lens group with positive focal power, a first zoom lens group with negative focal power, a second fixed lens group with positive focal power, a focusing lens group with negative focal power, a second zoom lens group with positive focal power and a third fixed lens group with negative focal power, the first fixed lens group comprises a first lens with negative focal power, a second lens with positive focal power, a third lens with positive focal power and a fourth lens with positive focal power; the first zoom lens group comprises a fifth lens with negative focal power, a sixth lens with negative focal power and a seventh lens with positive focal power; the second fixed lens group comprises an eighth lens with positive focal power, a ninth lens with positive or negative focal power, a tenth lens with negative focal power and an eleventh lens with positive focal power; and the third fixed lens group comprises a fourteenth lens with negative focal power. The zoom lens is small in size, large in multiplying power, large in aperture and capable of realizing infrared high and low temperature confocal.

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] 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 sophistication, which also puts more stringent requirements on mainstream zoom lenses.

[0003] Currently, 1 / 1.8” chips are gradually being widely used, but traditional zoom lenses usually use 1 / 2.7” chips. Traditional zoom lenses using 1 / 1.8” chips have problems such as small magnification, small aperture, and infrared non-confocality. Summary of the Invention

[0004] The embodiment of the present invention provides a zoom lens that is compact, has a large magnification, a large aperture, and infrared high and low temperature confocality, and is capable of being used with a 1 / 1.8" chip for high image quality.

[0005] An embodiment of the present invention provides a zoom lens, comprising a first fixed lens group with positive optical power, a first zoom lens group with negative optical power, a second fixed lens group with positive optical power, a focusing lens group with negative optical power, a second zoom lens group with positive optical power, and a third fixed lens group with negative optical power, arranged in sequence along an optical axis from the object side to the image side.

[0006] The first fixed lens group includes a first lens with negative optical power, a second lens with positive optical power, a third lens with positive optical power, and a fourth lens with positive optical power, which are arranged in sequence from the object side to the image side along the optical axis;

[0007] The first zoom lens group includes a fifth lens with negative optical power, a sixth lens with negative optical power, and a seventh lens with positive optical power, which are arranged in sequence from the object side to the image side along the optical axis;

[0008] The second fixed lens group includes an eighth lens with positive optical power, a ninth lens with positive or negative optical power, a tenth lens with negative optical power, and an eleventh lens with positive optical power, which are arranged in sequence from the object side to the image side along the optical axis;

[0009] The third fixed lens group includes a fourteenth lens with negative optical power.

[0010] Optionally, the focusing lens group includes a twelfth lens with negative optical power;

[0011] The second zoom lens group includes a thirteenth lens having positive optical power;

[0012] The thirteenth lens is a glass aspherical lens.

[0013] Optionally, the fourteenth lens is a concave-convex lens, and / or the twelfth lens is a concave-concave lens.

[0014] Optionally, the focal length of the first fixed lens group is F1, the focal length of the first zoom lens group is F2, the focal length of the second fixed lens group is F3, the focal length of the focus lens group is F4, the focal length of the second zoom lens group is F5, the focal length of the third fixed lens group is F6, and the focal length of the zoom lens at the wide-angle end is FW, satisfying at least one of the following conditions:

[0015] ;

[0016] ;

[0017] ;

[0018] ;

[0019] ;

[0020] .

[0021] Optionally, the distance between the closest position of the focus lens group to the image plane and the farthest position from the image plane during the movement is S4, and the distance between the closest position of the second zoom lens group to the image plane and the farthest position from the image plane during the movement is S5, satisfying:

[0022] .

[0023] Optionally, it further includes an aperture, wherein the aperture is located between the first zoom lens group and the second fixed lens group;

[0024] The eighth lens is a glass aspherical lens;

[0025] The second fixed lens group includes a cemented lens group consisting of at least two lenses.

[0026] Optionally, a refractive index of the fifth lens is nd5, a refractive index of the sixth lens is nd6, a refractive index of the seventh lens is nd7, a refractive index of the eighth lens is nd8, a refractive index of the fourteenth lens is nd14, an Abbe number of the fifth lens is vd5, an Abbe number of the sixth lens is vd6, an Abbe number of the seventh lens is vd7, an Abbe number of the eighth lens is vd8, and an Abbe number of the fourteenth lens is vd14, satisfying at least one of the following conditions:

[0027] ; ;

[0028] ; ;

[0029] ; ;

[0030] ; ;

[0031] ; .

[0032] Optionally, it further includes an aperture, wherein the aperture is located between the first zoom lens group and the second fixed lens group;

[0033] The focal length of the zoom lens at the wide-angle end is FW, and the diameter of the image formed by the aperture relative to the first fixed lens group and the first zoom lens group when the zoom lens is at the wide-angle end is EPDW.

[0034] satisfy: .

[0035] Optionally, the maximum lens diameter in the focus lens group is ΦG1, and the total optical length of the zoom lens at the wide-angle end is TTL.

[0036] satisfy: .

[0037] Optionally, the sixth lens is a glass aspherical lens;

[0038] And / or, the first lens and the second lens are cemented together to form a cemented lens group.

[0039] An embodiment of the present invention provides a six-component zoom lens, including a first fixed lens group, a first zoom lens group, a second fixed lens group, a focusing lens group, a second zoom lens group, and a third fixed lens group. By changing the positions of the first zoom lens group, the second fixed 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. The first fixed lens group can adjust the distortion of the zoom lens and improve the imaging effect of the zoom lens; the negative optical power of the first zoom lens group can ensure that the light has a larger diameter before entering the aperture, thereby increasing the aperture of the zoom lens. The zoom lens achieves short-focus confocality in the 436nm-850nm band under a 1 / 1.8" target surface, has a larger aperture, and has higher image quality, making it suitable for use in a wider range of situations. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic structural diagram of the zoom lens at the wide-angle end provided in the first embodiment of the present invention;

[0041] Figure 2 A schematic structural diagram of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0042] Figure 3 The axial aberration curve of the zoom lens provided in the first embodiment of the present invention at the wide-angle end;

[0043] Figure 4-Figure 9 This is a ray fan diagram of the zoom lens provided in the first embodiment of the present invention at the wide-angle end;

[0044] Figure 10 A diagram of vertical axial chromatic aberration of the zoom lens provided in Example 1 of the present invention at the wide-angle end;

[0045] Figure 11 The axial aberration curve of the zoom lens provided in the first embodiment of the present invention at the telephoto end;

[0046] Figure 12-17 A ray fan diagram of the zoom lens at the telephoto end provided by the first embodiment of the present invention;

[0047] Figure 18 A diagram of vertical axial chromatic aberration of the zoom lens provided in Example 1 of the present invention at the telephoto end;

[0048] Figure 19 A schematic structural diagram of the zoom lens at the wide-angle end provided in the second embodiment of the present invention;

[0049] Figure 20 A schematic structural diagram of a zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0050] Figure 21 The axial aberration curve of the zoom lens provided in the second embodiment of the present invention at the wide-angle end;

[0051] Figure 22-Figure 27 This is a ray fan diagram of the zoom lens provided in the second embodiment of the present invention at the wide-angle end;

[0052] Figure 28 A diagram of vertical axial chromatic aberration of the zoom lens provided in Example 2 of the present invention at the wide-angle end;

[0053] Figure 29 The axial aberration curve of the zoom lens provided in the second embodiment of the present invention at the telephoto end;

[0054] Figure 30-Figure 35 A ray fan diagram of the zoom lens at the telephoto end provided by the second embodiment of the present invention;

[0055] Figure 36 A diagram of vertical axial chromatic aberration of the zoom lens provided in the second embodiment of the present invention at the telephoto end;

[0056] Figure 37 A schematic structural diagram of the zoom lens at the wide-angle end provided in the third embodiment of the present invention;

[0057] Figure 38 A schematic diagram of the structure of the zoom lens at the telephoto end provided by the third embodiment of the present invention;

[0058] Figure 39 This is the axial aberration curve of the zoom lens provided in the third embodiment of the present invention at the wide-angle end;

[0059] Figures 40-45 This is a ray fan diagram of the zoom lens at the wide-angle end provided by the third embodiment of the present invention;

[0060] Figure 46 A diagram of vertical axial chromatic aberration of the zoom lens provided in Example 3 of the present invention at the wide-angle end;

[0061] Figure 47 The axial aberration curve of the zoom lens provided in the third embodiment of the present invention at the telephoto end;

[0062] Figures 48-53 This is a ray fan diagram of the zoom lens at the telephoto end provided by the third embodiment of the present invention;

[0063] Figure 54 This is a diagram of vertical axis chromatic aberration of the zoom lens provided in Example 3 of the present invention at the telephoto end. DETAILED DESCRIPTION

[0064] 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.

[0065] Example 1

[0066] 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 with positive optical focal length, a first zoom lens group G2 with negative optical focal length, a second fixed lens group G3 with positive optical focal length, a focusing lens group G4 with negative optical focal length, a second zoom lens group G5 with positive optical focal length, and a third fixed lens group G6 with negative optical focal length, which are arranged in sequence from the object side to the image side along the optical axis.

[0067] The first fixed lens group G1 includes a first lens L1 with negative optical focal power, a second lens L2 with positive optical focal power, a third lens L3 with positive optical focal power and a fourth lens L4 with positive optical focal power, which are arranged in sequence from the object side to the image side along the optical axis; the first zoom lens group G2 includes a fifth lens L5 with negative optical focal power, a sixth lens L6 with negative optical focal power and a seventh lens L7 with positive optical focal power, which are arranged in sequence from the object side to the image side along the optical axis; the second fixed lens group G3 includes an eighth lens L8 with positive optical focal power, a ninth lens L9 with positive or negative optical focal power, a tenth lens L10 with negative optical focal power and an eleventh lens L11 with positive optical focal power, which are arranged in sequence from the object side to the image side along the optical axis; the third fixed lens group G6 includes a fourteenth lens L14 with negative optical focal power.

[0068] An embodiment of the present invention provides a six-component zoom lens, including a first fixed lens group G1, a first zoom lens group G2, a second fixed lens group G3, a focusing lens group G4, a second zoom lens group G5, and a third fixed lens group G6. By changing the positions of the first zoom lens group G2, the second fixed lens group G3, and the focusing lens group G4 on the optical axis, the zoom lens can be switched between the wide-angle end and the telephoto end. Among them, the first fixed lens group G1 can adjust the distortion of the zoom lens and improve the imaging effect of the zoom lens; the negative optical focal length of the first zoom lens group G2 can ensure that the light has a larger diameter before entering the aperture, thereby increasing the aperture of the zoom lens. The zoom lens achieves short-focus confocality in the 436nm-850nm band under a 1 / 1.8″ target surface, and has a larger aperture and higher image quality, which is suitable for usage needs in a wider range of situations.

[0069] Optionally, the focusing lens group G4 includes a twelfth lens L12 with negative optical power; the second zoom lens group G5 includes a thirteenth lens L13 with positive optical power; and the thirteenth lens L13 is a glass aspherical lens. The focusing lens group G4 and the second zoom lens group G5 only include one lens. The single lens group structure can control the volume of the group itself, thereby obtaining a larger movable distance in the overall structure of the zoom lens, increasing the variable magnification range of the zoom lens, and broadening the application scenarios of the zoom lens. The lenses in the second zoom lens group G5 are glass aspherical lenses. The second zoom lens group G5 with a longer stroke needs to compensate for the aberrations of the entire zoom lens during movement. The use of aspherical lenses has better compensation effects and higher imaging quality.

[0070] Optionally, the fourteenth lens L14 is a concave-convex lens, and / or the twelfth lens L12 is a concave-concave lens. The object-side surface of the concave-convex lens is concave toward the object side, and the image-side surface of the concave-convex lens is convex toward the image side. The concave-concave lens is a biconcave lens. The concave-concave lens of the twelfth lens L12 can ensure that the zoom lens has a good zoom effect; the fourteenth lens L14 serves as the third fixed lens group G6, and the fourteenth lens L14 is a concave-convex lens, which can control the emission angle of the rear end pipeline of the zoom lens, achieving a larger light height at the image plane, meeting the requirements of large target surface use.

[0071] Optionally, the focal length of the first fixed lens group G1 is F1, the focal length of the first zoom lens group G2 is F2, the focal length of the second fixed lens group G3 is F3, the focal length of the focus lens group G4 is F4, the focal length of the second zoom lens group G5 is F5, the focal length of the third fixed lens group G6 is F6, and the focal length of the zoom lens at the wide-angle end is FW, satisfying at least one of the following conditions: ; ; ; ; ; By using this focal length combination, a reasonable combination of optical powers is achieved, allowing light to pass through the zoom lens more smoothly, and to a large extent correcting the impact of the zoom lens's advanced aberrations on image quality.

[0072] Optionally, the distance between the closest position to the image plane and the farthest position from the image plane of the focus lens group G4 during movement is S4, and the distance between the closest position to the image plane and the farthest position from the image plane of the second zoom lens group G5 during movement is S5, satisfying: By controlling the travel ratio of the focus lens group G4 and the second zoom lens group G5 during movement, the focus lens group G4 and the second zoom lens group G5 can overlap in their moving areas, but they will not collide during zooming, thus minimizing the size of the zoom lens.

[0073] Optionally, the zoom lens further includes an aperture STO, located between the first zoom lens group G2 and the second fixed lens group G3; the eighth lens L8 is a glass aspherical lens; and the second fixed lens group G3 includes a cemented lens group consisting of at least two lenses. Light passing through the aperture STO generates higher-order aberrations, and the best way to reduce these aberrations at the rear end is to reduce them at the front end. The eighth lens L8 is a glass aspherical lens, which has a good correction effect on higher-order aberrations. Combined with the cemented lens group in the second fixed lens group G3, this not only improves image quality but also corrects the aberrations of the second fixed lens group G3 itself, ensuring that the zoom lens maintains high image quality throughout the entire zooming process.

[0074] Illustratively, the cemented lens group in the second fixed lens group G3 may include two adjacent lenses, three adjacent lenses, or four adjacent lenses among the eighth lens L8, the ninth lens L9, the tenth lens L10, and the eleventh lens L11. In one example, the tenth lens L10 and the eleventh lens L11 form a cemented lens group.

[0075] Optionally, the refractive index of the fifth lens L5 is nd5, the refractive index of the sixth lens L6 is nd6, the refractive index of the seventh lens L7 is nd7, the refractive index of the eighth lens L8 is nd8, the refractive index of the fourteenth lens L14 is nd14, the Abbe number of the fifth lens L5 is vd5, the Abbe number of the sixth lens L6 is vd6, the Abbe number of the seventh lens L7 is vd7, the Abbe number of the eighth lens L8 is vd8, and the Abbe number of the fourteenth lens L14 is vd14, satisfying at least one of the following conditions:

[0076] ; ;

[0077] ; ;

[0078] ; ;

[0079] ; ;

[0080] ; .

[0081] In the zoom lens, the first zoom lens group G2 in front of the aperture STO plays a leading role in adjusting the lens magnification. The use of the above-mentioned refractive index material in combination with the optical focal length of the lens can not only correct the aberrations but also control the high and low temperature conditions of the zoom lens. At the same time, the volume of the first zoom lens group G2 is reduced, leaving more room for movement in the zoom lens, expanding the lens magnification while meeting the use requirements under different temperature conditions. In addition, the setting of the eighth lens L8 in the second fixed lens group G3 also has the same effect. The fourteenth lens L14 in the third fixed lens group G6 uses the above-mentioned refractive index material, which can be combined with the shape of the lens to better control the output angle of the zoom lens light, and control the imaging quality and target surface size of the zoom lens.

[0082] Optionally, the zoom lens further includes an aperture STO, which is located between the first zoom lens group G2 and the second fixed lens group G3. When the zoom lens has a focal length of FW at the wide-angle end, a diameter of an image formed by the aperture STO relative to the first fixed lens group G1 and the first zoom lens group G2 at the wide-angle end is EPDW, satisfying: Placing the aperture STO between the first zoom lens group G2 and the second fixed lens group G3 can balance the lens aberrations and prevent the problem of high-order aberrations generated by the lens being unable to be corrected at the rear end of the lens, which would lead to a decrease in the imaging quality of the zoom lens. Ensuring the ratio of the focal length at the wide-angle end of the zoom lens to the entrance pupil diameter at the wide-angle end of the zoom lens can control the imaging condition of the zoom lens and meet the needs of use in darker environments.

[0083] Optionally, the maximum lens diameter in the focus lens group G4 is ΦG1, and the total optical length of the zoom lens at the wide-angle end is TTL, satisfying: This setting can control the size of the lens, making the zoom lens more compact while maximizing the field of view and light intake of the zoom lens to meet the needs of use in different environments.

[0084] Optionally, the sixth lens L6 is a glass aspherical lens; and / or the first lens L1 and the second lens L2 are cemented to form a cemented lens group.

[0085] In the zoom lens provided in this embodiment, the first fixed lens group G1, the first zoom lens group G2, the second fixed lens group G3, the focus lens group G4, the second zoom lens group G5 and the third fixed lens group G6 can be arranged in one lens barrel ( Figure 1 The first fixed lens group G1, the second fixed lens group G3, and the third fixed lens group G6 are fixed in position within the lens barrel, while the first zoom lens group G2, the focus lens group G4, and the second zoom lens group G5 can reciprocate along the optical axis within the lens barrel. Through the combined movement of the first zoom lens group G2, the focus lens group G4, and the second zoom lens group G5, the focal length of the zoom lens can be continuously changed from the wide-angle end to the telephoto end, ensuring high image quality at all focal positions of the zoom lens.

[0086] It can be understood that in the process of zooming of the zoom lens by moving the first zoom lens group G2, the focusing lens group G4 and the second zoom lens group G5, when the focal length is the shortest, the zoom lens is located at the wide-angle end, and when the focal length is the longest, the zoom lens is located 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 lengths or shapes.

[0087] For example, the zoom lens may further include a flat glass plate CG. The flat glass plate CG is located on the side of the fourteenth lens L14 away from the first lens L1 and on the side of the fourteenth lens L14 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.

[0088] Exemplarily, the aspheric lens (including a glass aspheric lens) of the zoom lens satisfies the following formula:

[0089]

[0090] Where Z is the axial distance from the surface at a height r perpendicular to the optical axis to the vertex of the surface along the optical axis; c represents the curvature at the vertex of the aspheric surface; are the high-order aspheric coefficients corresponding to the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth orders of the aspheric surface, The combination becomes the high-order terms corresponding to the aspheric surface. They are 4, 6, 8, 10, 12, 14 and 16 respectively.

[0091] Table 1: Design values ​​of the zoom lens in Example 1

[0092]

[0093] 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 2 As 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. "Inf" in the Radius of Curvature column indicates that the surface is flat and has an infinite radius of curvature. The unit is mm. The value in the Thickness column represents the axial distance from the current surface to the center of the next surface, in mm. The Refractive Index column indicates 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.

[0094] Table 2 Zoom interval design values ​​of the zoom lens in Example 1

[0095]

[0096] The zoom intervals in Table 2 are the different interval values ​​of the zoom lens at the wide-angle end and the telephoto end.

[0097] Table 3 Aspheric coefficients of the zoom lens in Example 1

[0098]

[0099] The meaning of the "surface number" column in Table 3 is consistent with that in Table 1. For example, surface number 3 also represents the front surface of the second lens L2. "E" in each embodiment of the present invention represents an index with base 10.

[0100] For example, in Example 1, the maximum diameter of the image plane of the zoom lens at the wide-angle end is 9.2 mm, and the maximum diameter of the image plane at the telephoto end is 9.2 mm. The focal length of the zoom lens at the wide-angle end is 6.8 mm, and the focal length at the telephoto end is 115.71 mm. The zoom lens is applicable to the wavelength range of 436 nm to 850 nm at the wide-angle end, and to the wavelength range of 436 nm to 656 nm at the telephoto end. The F / # (i.e., F-number) of the zoom lens is 1.61 to 3.52. The total optical length of the zoom lens at the wide-angle and telephoto ends is 92.48 mm.

[0101] Figure 3 The axial aberration curve of the zoom lens at the wide-angle end is shown. The main wavelength is 546.074nm. The horizontal direction represents the axial offset relative to the specified target surface, and the unit is millimeter (mm). Figure 3 It can be seen that the axial aberrations at different wavelengths and normalized apertures of 0 to 1.0 are all controlled within a reasonable range, indicating that the axial chromatic aberration of this zoom lens at the wide-angle end is well controlled, meeting the basic requirements for clear night imaging and achieving clear imaging across the entire band.

[0102] like Figure 4-Figure 9 As shown. The horizontal axis is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, at which point all light rays in the field of view focus on the same point on the image plane; the vertical axis 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 magnitude of the vertical axis chromatic aberration. Figure 4-Figure 9 As can be seen, this zoom lens's curves for all wavelengths in all fields of view are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, the curves for each color have no noticeable dispersion, indicating that this zoom lens also effectively corrects chromatic aberration, ensuring the lens's ability to produce clear images across the entire wavelength range.

[0103] Figure 10The vertical axis chromatic aberration curve of the zoom lens at the wide-angle end is shown. The vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical axis vertex represents the maximum field of view. The main wavelength is 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (um). Figure 10 It can be seen that the vertical chromatic aberration at 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 across the entire band.

[0104] Figure 11 The axial aberration curve of the zoom lens at the telephoto end is shown, with the main wavelength being 546.074nm. The horizontal direction represents the axial offset relative to the specified target surface, in millimeters (mm). Figure 11 It can be seen that the axial aberrations at different wavelengths and normalized apertures of 0 to 1.0 are all controlled within a reasonable range, indicating that the axial chromatic aberration of this zoom lens at the wide-angle end is well controlled, meeting the basic requirements for clear nighttime imaging and achieving clear imaging across the entire visible light band.

[0105] like Figure 12-17 As shown. The horizontal axis in the 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, at which point all light rays in the field of view focus on the same point on the image plane; the vertical axis 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 12-17 As can be seen, this zoom lens's curves for all wavelengths in all fields of view are closely aligned with the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, the curves for each color exhibit no significant dispersion, demonstrating that chromatic aberration is well corrected, ensuring the zoom lens's ability to produce clear images across the entire visible light band.

[0106] Figure 18 The vertical axis chromatic aberration curve of the zoom lens at the telephoto end is shown. The vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical axis vertex represents the maximum field of view. The main wavelength is 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (um). Figure 18 It can be seen that the vertical chromatic aberration at 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 wide-spectrum application requirements of the entire visible light band.

[0107] Example 2

[0108] Similarities with the above embodiment are not repeated here.

[0109] Table 4: Design values ​​of the zoom lens in Example 2

[0110]

[0111] Table 4 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. Figure 19 and Figure 20 As shown in .

[0112] Table 5 Zoom interval design values ​​of the zoom lens in Example 2

[0113]

[0114] The zoom intervals in Table 5 are the different interval values ​​of the zoom lens at the wide-angle end and the telephoto end.

[0115] Table 6 Aspheric coefficients of the zoom lens in Example 2

[0116]

[0117] The meaning of the "surface number" column in Table 6 is consistent with that in Table 4. "E" in each embodiment of the present invention represents an exponential number with base 10.

[0118] For example, in Example 2, the maximum diameter of the image plane of the zoom lens at the wide-angle end is 9.2 mm, and the maximum diameter of the image plane at the telephoto end is 9.2 mm. The focal length of the zoom lens at the wide-angle end is 6.94 mm, and the focal length at the telephoto end is 90.4 mm. The zoom lens is applicable to the wavelength range of 436 nm to 850 nm at the wide-angle end, and to the wavelength range of 436 nm to 656 nm at the telephoto end. The F / # (i.e., F-number) of the zoom lens is 1.60 to 3.52. The total optical length of the zoom lens at the wide-angle and telephoto ends is 96.13 mm.

[0119] Figure 21 The axial aberration curve of the zoom lens at the wide-angle end is shown. The main wavelength is 546.074nm. The horizontal direction represents the axial offset relative to the specified target surface, and the unit is millimeter (mm). Figure 21 It can be seen that the axial aberrations at different wavelengths and normalized apertures of 0 to 1.0 are all controlled within a reasonable range, indicating that the axial chromatic aberration of this zoom lens at the wide-angle end is well controlled, meeting the basic requirements for clear night imaging and achieving clear imaging across the entire band.

[0120] like Figure 22-Figure 27As shown. The horizontal axis is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, at which point all light rays in the field of view focus on the same point on the image plane; the vertical axis 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 magnitude of the vertical axis chromatic aberration. Figure 22-Figure 27 As can be seen, this zoom lens's curves for all wavelengths in all fields of view are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, the curves for each color have no noticeable dispersion, indicating that this zoom lens also effectively corrects chromatic aberration, ensuring the lens's ability to produce clear images across the entire wavelength range.

[0121] Figure 28 The vertical axis chromatic aberration curve of the zoom lens at the wide-angle end is shown. The vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical axis vertex represents the maximum field of view. The main wavelength is 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (um). Figure 28 It can be seen that the vertical chromatic aberration at 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 across the entire band.

[0122] Figure 29 The axial aberration curve of the zoom lens at the telephoto end is shown, with the main wavelength being 546.074nm. The horizontal direction represents the axial offset relative to the specified target surface, in millimeters (mm). Figure 29 It can be seen that the axial aberrations at different wavelengths of 0.3~1.0 normalized aperture are all controlled within a reasonable range, indicating that the axial chromatic aberration of this zoom lens at the wide-angle end is well controlled, meeting the basic requirements for clear night imaging and achieving clear imaging across the entire visible light band.

[0123] like Figure 30-Figure 35 As shown. The horizontal axis in the 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, at which point all light rays in the field of view focus on the same point on the image plane; the vertical axis 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 30-Figure 35 As can be seen, this zoom lens's curves for all wavelengths in all fields of view are closely aligned with the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, the curves for each color exhibit no significant dispersion, demonstrating that chromatic aberration is well corrected, ensuring the zoom lens's ability to produce clear images across the entire visible light band.

[0124] Figure 36The vertical axis chromatic aberration curve of the zoom lens at the telephoto end is shown. The vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical axis vertex represents the maximum field of view. The main wavelength is 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (um). Figure 36 It can be seen that the vertical chromatic aberration at 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 wide-spectrum application requirements of the entire visible light band.

[0125] Example 3

[0126] Similarities with the above embodiment are not repeated here.

[0127] Table 7: Design values ​​of the zoom lens in Example 3

[0128]

[0129] Table 7 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 7 can be Figure 37 and Figure 38 As shown in .

[0130] Table 8 Zoom interval design values ​​of the zoom lens in Example 3

[0131]

[0132] The zoom intervals in Table 8 are the different interval values ​​of the zoom lens at the wide-angle end and the telephoto end.

[0133] Table 9 Aspheric coefficients of the zoom lens in Example 3

[0134]

[0135] The meaning of the "surface number" column in Table 9 is consistent with that in Table 7. "E" in each embodiment of the present invention represents an exponential number with base 10.

[0136] For example, in Example 3, the maximum diameter of the image plane of the zoom lens at the wide-angle end is 9.2 mm, and the maximum diameter of the image plane at the telephoto end is 9.2 mm. The focal length of the zoom lens at the wide-angle end is 5.78 mm, and the focal length at the telephoto end is 105.3 mm. The zoom lens is applicable to the wavelength range of 436 nm to 850 nm at the wide-angle end, and to the wavelength range of 436 nm to 656 nm at the telephoto end. The F / # (i.e., F-number) of the zoom lens is 1.60 to 3.49. The total optical length of the zoom lens at the wide-angle and telephoto ends is 96.28 mm.

[0137] Figure 39 The axial aberration curve of the zoom lens at the wide-angle end is shown. The main wavelength is 546.074nm. The horizontal direction represents the axial offset relative to the specified target surface, and the unit is millimeter (mm). Figure 39 It can be seen that the axial aberrations at different wavelengths and normalized apertures of 0 to 1.0 are all controlled within a reasonable range, indicating that the axial chromatic aberration of this zoom lens at the wide-angle end is well controlled, meeting the basic requirements for clear night imaging and achieving clear imaging across the entire band.

[0138] like Figures 40-45 As shown. The horizontal axis is the normalized beam aperture, and the vertical axis is the vertical axis aberration. Ideally, each curve should completely coincide with the horizontal axis, at which point all light rays in the field of view focus on the same point on the image plane; the vertical axis 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 magnitude of the vertical axis chromatic aberration. Figures 40-45 As can be seen, this zoom lens's curves for all wavelengths in all fields of view are very close to the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, the curves for each color have no noticeable dispersion, indicating that this zoom lens also effectively corrects chromatic aberration, ensuring the lens's ability to produce clear images across the entire wavelength range.

[0139] Figure 46 The vertical axis chromatic aberration curve of the zoom lens at the wide-angle end is shown. The vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical axis vertex represents the maximum field of view. The main wavelength is 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (um). Figure 46 It can be seen that the vertical chromatic aberration at 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 across the entire band.

[0140] Figure 47 The axial aberration curve of the zoom lens at the telephoto end is shown, with the main wavelength being 546.074nm. The horizontal direction represents the axial offset relative to the specified target surface, in millimeters (mm). Figure 47 It can be seen that the axial aberrations at different wavelengths and normalized apertures of 0 to 1.0 are all controlled within a reasonable range, indicating that the axial chromatic aberration of this zoom lens at the wide-angle end is well controlled, meeting the basic requirements for clear nighttime imaging and achieving clear imaging across the entire visible light band.

[0141] like Figures 48-53As shown. The horizontal axis in the 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, at which point all light rays in the field of view focus on the same point on the image plane; the vertical axis 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. Figures 48-53 As can be seen, this zoom lens's curves for all wavelengths in all fields of view are closely aligned with the horizontal axis, indicating that vertical aberrations at each wavelength are well corrected. Furthermore, the curves for each color exhibit no significant dispersion, demonstrating that chromatic aberration is well corrected, ensuring the zoom lens's ability to produce clear images across the entire visible light band.

[0142] Figure 54 The vertical axis chromatic aberration curve of the zoom lens at the telephoto end is shown. The vertical direction represents the normalized aperture, 0 represents the optical axis, and the vertical axis vertex represents the maximum field of view. The main wavelength is 546.074nm, and the horizontal direction represents the offset relative to the main wavelength in micrometers (um). Figure 54 It can be seen that the vertical chromatic aberration at 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 wide-spectrum application requirements of the entire visible light band.

[0143] Table 10 Parameter design values ​​of various embodiments

[0144]

[0145] 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 lens comprises a first fixed lens group with positive optical power, a first zoom lens group with negative optical power, a second fixed lens group with positive optical power, a focusing lens group with negative optical power, a second zoom lens group with positive optical power, and a third fixed lens group with negative optical power, which are arranged in sequence from the object side to the image side along the optical axis; The first fixed lens group includes a first lens with negative optical power, a second lens with positive optical power, a third lens with positive optical power, and a fourth lens with positive optical power, which are arranged in sequence from the object side to the image side along the optical axis; The first zoom lens group includes a fifth lens with negative optical power, a sixth lens with negative optical power, and a seventh lens with positive optical power, which are arranged in sequence from the object side to the image side along the optical axis; The second fixed lens group includes an eighth lens with positive optical power, a ninth lens with positive or negative optical power, a tenth lens with negative optical power, and an eleventh lens with positive optical power, which are arranged in sequence from the object side to the image side along the optical axis; The third fixed lens group includes a fourteenth lens with negative optical power.

2. The zoom lens according to claim 1, wherein: The focusing lens group includes a twelfth lens with negative optical power; The second zoom lens group includes a thirteenth lens having positive optical power; The thirteenth lens is a glass aspherical lens.

3. The zoom lens according to claim 2, wherein: The fourteenth lens is a concave-convex lens, and / or the twelfth lens is a concave-concave lens.

4. The zoom lens according to claim 1, wherein: The focal length of the first fixed lens group is F1, the focal length of the first zoom lens group is F2, the focal length of the second fixed lens group is F3, the focal length of the focus lens group is F4, the focal length of the second zoom lens group is F5, the focal length of the third fixed lens group is F6, and the focal length of the zoom lens at the wide-angle end is FW, satisfying at least one of the following conditions: 。 5. The zoom lens according to claim 1, wherein: The distance between the closest position of the focus lens group to the image plane and the farthest position from the image plane during the movement is S4, and the distance between the closest position of the second zoom lens group to the image plane and the farthest position from the image plane during the movement is S5, satisfying: 。 6. The zoom lens according to claim 1, wherein: Also comprising an aperture stop, the aperture stop being located between the first zoom lens group and the second fixed lens group; The eighth lens is a glass aspherical lens; The second fixed lens group includes a cemented lens group consisting of at least two lenses.

7. The zoom lens according to claim 1, wherein: The refractive index of the fifth lens is nd5, the refractive index of the sixth lens is nd6, the refractive index of the seventh lens is nd7, the refractive index of the eighth lens is nd8, the refractive index of the fourteenth lens is nd14, the Abbe number of the fifth lens is vd5, the Abbe number of the sixth lens is vd6, the Abbe number of the seventh lens is vd7, the Abbe number of the eighth lens is vd8, and the Abbe number of the fourteenth lens is vd14, satisfying at least one of the following conditions: 。 8. The zoom lens according to claim 1, wherein: Also comprising an aperture stop, the aperture stop being located between the first zoom lens group and the second fixed lens group; The focal length of the zoom lens at the wide-angle end is FW, and the diameter of the image formed by the aperture relative to the first fixed lens group and the first zoom lens group when the zoom lens is at the wide-angle end is EPDW. satisfy: .

9. The zoom lens according to claim 1, wherein: The maximum lens diameter in the focus lens group is ΦG1, and the total optical length of the zoom lens at the wide-angle end is TTL. satisfy: .

10. The zoom lens according to claim 1, wherein The sixth lens is a glass aspherical lens; And / or, the first lens and the second lens are cemented together to form a cemented lens group.

Images