Zoom projection lens and imaging device

Abstract

The invention relates to the field of optics, in particular to a zoom projection lens and an imaging device, which sequentially comprise a focusing lens group with negative focal power, a first fixed lens group with negative focal power, a first zoom lens group with negative focal power, a second zoom lens group with positive focal power and a third zoom lens group with positive focal power from an object plane side to an image plane side, a fourth zoom lens group, and a second fixed lens group with positive focal power; the zoom projection lens satisfies the following conditional expressions: fno is less than 1.7; ft / fw is less than 2; wherein fno is the number of apertures of the zoom projection lens, ft is the focal length of the zoom projection lens in a telescopic state, and fw is the focal length of the zoom projection lens in a wide-angle state. According to the zoom projection lens provided by the invention, the brightness of the zoom projection lens is greatly increased, the use of a user is facilitated, and meanwhile, the resolving power of the zoom projection lens is greatly increased and the imaging quality of the zoom projection lens is improved by continuously using a large number of zoom lens groups.

Description

Technical Field

[0001] This invention relates to the field of optics, specifically to a zoom projection lens and an imaging device. Background Technology

[0002] A projection lens, also known as a projector lens, is the core optical component of a projector. Based on projection distance, they are categorized into short-throw, medium-throw, long-throw, and special types such as reflective and fisheye lenses. They are widely used in education, engineering, and home applications. The core parameter, transmittance, is the ratio of projection distance to screen width. Short-throw lenses have a transmittance of less than 1, while ultra-short-throw lenses can reach 0.25, enabling the projection of large images from short distances.

[0003] Currently, existing projection lenses are generally suitable for conference scenarios and have no problem with some conventional projections. However, for the projection of some intricate images, the resolution of ordinary projection lenses will be insufficient. Summary of the Invention

[0004] This invention addresses existing technical problems by providing a zoom projection lens and imaging device. While achieving projection, it significantly increases the brightness of the zoom projection lens, making it easier for users to operate. Furthermore, the use of a large number of continuous zoom lens groups greatly enhances the resolution and imaging quality of the zoom projection lens.

[0005] The technical solution provided by this invention is as follows: A zoom projection lens, wherein the zoom projection lens is composed of a negative optical power focusing lens group, a negative optical power first fixed lens group, a negative optical power first zoom lens group, a positive optical power second zoom lens group, a positive optical power third zoom lens group, a fourth zoom lens group, and a positive optical power second fixed lens group from the object plane side to the image plane side. The first zoom lens group, the second zoom lens group, the third zoom lens group, and the fourth zoom lens group move along the main optical axis of the zoom projection lens; The focusing lens group consists of a first focusing lens with negative optical power and a second focusing lens with negative optical power, sequentially from the object plane side to the image plane side. The first fixed lens group is a first fixed lens with negative optical power; The second fixed lens group is a second fixed lens with positive optical power; The zoom projection lens satisfies the following condition: fno < 1.7; ft / fw < 2; Wherein, fno is the aperture number of the zoom projection lens, ft is the focal length of the zoom projection lens in telephoto mode, and fw is the focal length of the zoom projection lens in wide-angle mode.

[0006] By defining the structure and parameters described above, the brightness of the zoom projection lens is greatly increased while achieving projection, making it easier for users to operate. At the same time, the use of a large number of continuous zoom lens groups greatly increases the resolution and image quality of the zoom projection lens.

[0007] Furthermore, the first zoom lens group consists of a first zoom lens with negative optical power and a second zoom lens with positive optical power, sequentially from the object plane side to the image plane side; The second zoom lens group consists of a third zoom lens with positive optical power and a fourth zoom lens with negative optical power, arranged sequentially from the object plane side to the image plane side, and the third zoom lens and the fourth zoom lens are cemented together. The third zoom lens group is a fifth zoom lens with positive optical power.

[0008] Furthermore, each of the first to fourth zoom lens groups includes at least one aspherical lens.

[0009] In this technical solution, the use of aspherical lenses reduces the number of lenses inside the zoom projection lens, thereby reducing the size of the zoom projection lens.

[0010] Furthermore, the fourth zoom lens group consists of a sixth zoom lens with negative optical power, a seventh zoom lens with positive optical power, an eighth zoom lens with negative optical power, a ninth zoom lens with positive optical power, a tenth zoom lens with negative optical power, and an eleventh zoom lens with positive optical power, from the object plane side to the image plane side. The eighth zoom lens, the ninth zoom lens, and the tenth zoom lens together form a cemented triplet lens.

[0011] Furthermore, the fourth zoom lens group consists of a seventh zoom lens with positive optical power, an eighth zoom lens with negative optical power, a ninth zoom lens with positive optical power, a tenth zoom lens with negative optical power, an eleventh zoom lens with positive optical power, and a twelfth zoom lens with positive optical power, from the object plane side to the image plane side. The eighth zoom lens, the ninth zoom lens, and the tenth zoom lens together form a cemented triplet lens.

[0012] Furthermore, the zoom projection lens satisfies the following condition: fG5 / fw < 10; fG6 / fw < -1000; Wherein, fG5 is the focal length of the third zoom lens group, and fG6 is the focal length of the fourth zoom lens group.

[0013] In this technical solution, by limiting the above parameters, the chromatic aberration and coma of the zoom projection lens are greatly reduced, thereby increasing the imaging quality of the zoom projection lens.

[0014] Furthermore, the zoom projection lens satisfies the following condition: fG5 / fw > 124; fG6 / fw < 10; Wherein, fG5 is the focal length of the third zoom lens group, and fG6 is the focal length of the fourth zoom lens group.

[0015] In this technical solution, by limiting the above parameters, the chromatic aberration and coma of the zoom projection lens are greatly reduced, thereby increasing the imaging quality of the zoom projection lens.

[0016] Furthermore, the first to fourth zoom lens groups move in the same direction.

[0017] In this technical solution, when the moving directions of multiple zoom lens groups are the same, the travel of multiple zoom lens groups can overlap, which greatly reduces the degree required for zoom projection lenses and realizes the miniaturization of zoom projection lenses.

[0018] Furthermore, the zoom projection lens satisfies the following condition: 1 < XG4 / fw < 2; Wherein, XG4 is the maximum moving distance of the second zoom lens group, and XG5 is the maximum moving distance of the third zoom lens group.

[0019] In this technical solution, by limiting the moving distance of the second zoom lens group, the length required for the zoom lens group is reduced while achieving zoom projection lens magnification, thus realizing the miniaturization of the second zoom lens group.

[0020] Furthermore, the zoom projection lens satisfies the following condition: XG3 / XG4 < 0.3; XG6 / XG4 < 0.7; Wherein, XG3 is the maximum moving distance of the first zoom lens group, and XG6 is the maximum moving distance of the fourth zoom lens group.

[0021] In this technical solution, by limiting the above parameters, the volume of the first and fourth zoom lens groups is greatly reduced while achieving zoom projection lens zoom, thus realizing miniaturization of zoom projection lens.

[0022] Furthermore, the first focusing lens is an aspherical lens; The zoom projection lens satisfies the following condition: Φa1 / Φb1>1.8; Wherein, Φa1 is the outer diameter of the first focusing lens, and Φb1 is the outer diameter of the first fixed lens.

[0023] In this technical solution, by setting the first focusing lens closest to the object surface as an aspherical lens and increasing the outer diameter of the first focusing lens, the range of light received by the zoom projection lens is greatly increased, and the field of view of the zoom projection lens is increased.

[0024] One of the objectives of this invention is to provide an imaging device, comprising: a zoom projection lens; and an imaging element configured to receive an image formed by the zoom projection lens.

[0025] Compared with the prior art, the zoom projection lens and imaging device provided by the present invention have the following beneficial effects: 1. By limiting the structure and parameters mentioned above, the brightness of the zoom projection lens is greatly increased while achieving projection, making it easier for users to use. At the same time, the use of a large number of zoom lens groups in succession greatly increases the resolution of the zoom projection lens and improves the image quality of the zoom projection lens.

[0026] 2. When multiple zoom lens groups move in the same direction, their travel distances can overlap, greatly reducing the required size of the zoom projection lens and enabling miniaturization of the zoom projection lens.

[0027] 3. By limiting the moving distance of the second zoom lens group, the length required for the zoom lens group is reduced while achieving zoom projection lens magnification, thus realizing the miniaturization of the second zoom lens group. Attached Figure Description

[0028] The preferred embodiments will now be described in a clear and easy-to-understand manner, with reference to the accompanying drawings, to further explain the above-mentioned characteristics, technical features, advantages, and implementation methods of a zoom projection lens and imaging device.

[0029] Figure 1 This is a schematic diagram of the structure of a zoom projection lens according to the present invention; Figure 2 This is an aberration diagram of a zoom projection lens in a wide-angle state according to the present invention; Figure 3 This invention relates to a coma diagram of a zoom projection lens in a wide-angle state. Figure 4 This is an aberration diagram of a zoom projection lens in telephoto mode according to the present invention; Figure 5 This invention provides a coma diagram of a zoom projection lens in telephoto mode. Figure 6 This is a schematic diagram of another zoom projection lens of the present invention; Figure 7 This is an aberration diagram of another zoom projection lens in the wide-angle state according to the present invention; Figure 8This is another coma diagram of the wide-angle state of the zoom projection lens of the present invention; Figure 9 This is another aberration diagram of the zoom projection lens in telephoto mode according to the present invention; Figure 10 This is another coma diagram of the zoom projection lens in the telephoto state of the present invention.

[0030] Explanation of reference numerals: G1, Focusing lens group; G2, First fixed lens group; G3, First zoom lens group; G4, Second zoom lens group; G5, Third zoom lens group; G6, Fourth zoom lens group; G7, Second fixed lens group; G8, Auxiliary component; a1, First focusing lens; a2, Second focusing lens; b1, First fixed lens; b2, Second fixed lens; c1, First zoom lens; c2, Second zoom lens; c3, Third zoom lens; c4, Fourth zoom lens; c5, Fifth zoom lens; c6, Sixth zoom lens; c7, Seventh zoom lens; c8, Eighth zoom lens; c9, Ninth zoom lens; c10, Tenth zoom lens; c11, Eleventh zoom lens; c12, Twelfth zoom lens; STO, Aperture stop; P, Beam splitter prism. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] To keep the drawings concise, each figure only schematically shows the parts relevant to the invention, and these do not represent the actual structure of the product. Furthermore, to facilitate understanding, in some figures, only one of components with the same structure or function is schematically depicted, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one." Example 1

[0033] like Figure 1 and Figure 6 As shown, a zoom projection lens is composed of, from the object plane side to the image plane side, a focusing lens group G1 with negative optical power, a first fixed lens group G2 with negative optical power, a first zoom lens group G3 with negative optical power, a second zoom lens group G4 with positive optical power, a third zoom lens group G5 with positive optical power, a fourth zoom lens group G6, and a second fixed lens group G7 with positive optical power. The first zoom lens group G3, the second zoom lens group G4, the third zoom lens group G5, and the fourth zoom lens group G6 move along the main optical axis of the zoom projection lens. The focusing lens group G1 consists of a first focusing lens a1 with negative optical power and a second focusing lens a2 with negative optical power, from the object plane side to the image plane side. The first fixed lens group G2 is a first fixed lens b1 with negative optical power; The second fixed lens group G7 is a second fixed lens b2 with positive optical power; The zoom projection lens satisfies the following condition: fno < 1.7; ft / fw < 2; Wherein, fno is the aperture number of the zoom projection lens, ft is the focal length of the zoom projection lens in telephoto mode, and fw is the focal length of the zoom projection lens in wide-angle mode.

[0034] By defining the structure and parameters described above, the brightness of the zoom projection lens is greatly increased while achieving projection, making it easier for users to operate. At the same time, the use of a large number of continuous zoom lens groups greatly increases the resolution and image quality of the zoom projection lens.

[0035] The first zoom lens group G3 consists of a first zoom lens c1 with negative optical power and a second zoom lens c2 with positive optical power, from the object plane side to the image plane side. The second zoom lens group G4 is composed of a third zoom lens c3 with positive optical power and a fourth zoom lens c4 with negative optical power, from the object plane side to the image plane side, and the third zoom lens c3 and the fourth zoom lens c4 are cemented together. The third zoom lens group G5 is a fifth zoom lens c5 with positive optical power.

[0036] The first zoom lens group G3 to the fourth zoom lens group G6 each contain at least one aspherical lens.

[0037] In this embodiment, the use of aspherical lenses reduces the number of lenses inside the zoom projection lens, thereby reducing the size of the zoom projection lens.

[0038] The fourth zoom lens group G6 consists of, from the object plane side to the image plane side, a sixth zoom lens c6 with negative optical power, a seventh zoom lens c7 with positive optical power, an eighth zoom lens c8 with negative optical power, a ninth zoom lens c9 with positive optical power, a tenth zoom lens c10 with negative optical power, and an eleventh zoom lens c11 with positive optical power. The eighth zoom lens c8, the ninth zoom lens c9, and the tenth zoom lens c10 together form a cemented triplet lens.

[0039] or The fourth zoom lens group G6 consists of, from the object plane side to the image plane side, a seventh zoom lens c7 with positive optical power, an eighth zoom lens c8 with negative optical power, a ninth zoom lens c9 with positive optical power, a tenth zoom lens c10 with negative optical power, an eleventh zoom lens c11 with positive optical power, and a twelfth zoom lens c12 with positive optical power. The eighth zoom lens c8, the ninth zoom lens c9, and the tenth zoom lens c10 together form a cemented triplet lens.

[0040] The zoom projection lens satisfies the following condition: fG5 / fw < 10; fG6 / fw < -1000; Wherein, fG5 is the focal length of the third zoom lens group G5, and fG6 is the focal length of the fourth zoom lens group G6.

[0041] In this embodiment, by limiting the above parameters, the chromatic aberration and coma of the zoom projection lens are greatly reduced, thereby increasing the imaging quality of the zoom projection lens.

[0042] The zoom projection lens satisfies the following condition: fG5 / fw > 124; fG6 / fw < 10; Wherein, fG5 is the focal length of the third zoom lens group G5, and fG6 is the focal length of the fourth zoom lens group G6.

[0043] In this embodiment, by limiting the above parameters, the chromatic aberration and coma of the zoom projection lens are greatly reduced, thereby increasing the imaging quality of the zoom projection lens.

[0044] The first zoom lens group G3 to the fourth zoom lens group G6 move in the same direction.

[0045] When multiple zoom lens groups move in the same direction, their travel distances can overlap, greatly reducing the required size of the zoom projection lens and enabling miniaturization of the zoom projection lens.

[0046] The zoom projection lens satisfies the following condition: 1 < XG4 / fw < 2; Wherein, XG4 is the maximum moving distance of the second zoom lens group G4, and XG5 is the maximum moving distance of the third zoom lens group G5.

[0047] In this embodiment, by limiting the moving distance of the second zoom lens group G4, the length required for the zoom lens group is reduced while achieving zoom projection lens magnification, thus realizing the miniaturization of the second zoom lens group G4.

[0048] The zoom projection lens satisfies the following condition: XG3 / XG4 < 0.3; XG6 / XG4 < 0.7; Wherein, XG3 is the maximum moving distance of the first zoom lens group G3, and XG6 is the maximum moving distance of the fourth zoom lens group G6.

[0049] In this embodiment, by limiting the above parameters, the volume of the first zoom lens group G3 and the fourth zoom lens group G6 is greatly reduced while achieving zoom of the zoom projection lens, thus realizing the miniaturization of the zoom projection lens.

[0050] The first focusing lens a1 is an aspherical lens; The zoom projection lens satisfies the following condition: Φa1 / Φb1>1.8; Wherein, Φa1 is the outer diameter of the first focusing lens a1, and Φb1 is the outer diameter of the first fixed lens b1.

[0051] In this embodiment, by setting the first focusing lens a1 closest to the object surface as an aspherical lens and increasing the outer diameter of the first focusing lens a1, the range of light received by the zoom projection lens is greatly increased, and the field of view of the zoom projection lens is increased. Example 2

[0052] like Figures 1 to 5 As shown, a zoom projection lens is composed of, from the object plane side to the image plane side, a focusing lens group G1 with negative optical power, a first fixed lens group G2 with negative optical power, a first zoom lens group G3 with negative optical power, a second zoom lens group G4 with positive optical power, a third zoom lens group G5 with positive optical power, a fourth zoom lens group G6 with negative optical power, a second fixed lens group G7 with positive optical power, and an auxiliary component G8. The first zoom lens group G3, the second zoom lens group G4, the third zoom lens group G5, and the fourth zoom lens group G6 move along the main optical axis of the zoom projection lens. The focusing lens group G1 consists of a first focusing lens a1 with negative optical power and a second focusing lens a2 with negative optical power, from the object plane side to the image plane side. The first fixed lens group G2 is a first fixed lens b1 with negative optical power; The first zoom lens group G3 consists of a first zoom lens c1 with negative optical power and a second zoom lens c2 with positive optical power, from the object plane side to the image plane side. The second zoom lens group G4 is composed of a third zoom lens c3 with positive optical power and a fourth zoom lens c4 with negative optical power, from the object plane side to the image plane side, and the third zoom lens c3 and the fourth zoom lens c4 are cemented together. The third zoom lens group G5 is a fifth zoom lens c5 with positive optical power.

[0053] The fourth zoom lens group G6 consists of, from the object plane side to the image plane side, a seventh zoom lens c7 with positive optical power, an eighth zoom lens c8 with negative optical power, a ninth zoom lens c9 with positive optical power, a tenth zoom lens c10 with negative optical power, an eleventh zoom lens c11 with positive optical power, and a twelfth zoom lens c12 with positive optical power. The eighth zoom lens c8, the ninth zoom lens c9, and the tenth zoom lens c10 together form a cemented triplet lens.

[0054] The second fixed lens group G7 is a second fixed lens b2 with positive optical power; The auxiliary component G8 is a beam splitter P.

[0055] The basic lens data of the zoom projection lens in this embodiment is shown in Table 1, the variable parameters in Table 1 are shown in Table 2, and the aspherical coefficients are shown in Table 3.

[0056] The surface number column shows the surface number when the object-side surface is set as surface 1 and the numbering is increased sequentially towards the image side; the surface type column shows the surface type of a lens; the radius of curvature column shows the radius of curvature of a lens, where a positive radius of curvature indicates that the surface is curved towards the object side and a negative radius of curvature indicates that the surface is curved towards the image side; the center thickness column shows the surface spacing on the optical axis between each surface and the surface adjacent to it on the image side; the refractive index column shows the refractive index of a lens; and the Abbe number column shows the Abbe number of a lens.

[0057] In Table 2, the WIDE column indicates the specific values ​​of each variable parameter when the zoom projection lens is in the wide-angle end state, and the TELE column indicates the specific values ​​of each variable parameter when the zoom projection lens is in the telephoto end state.

[0058] In Table 3, K is the conic coefficient, and e is the scientific notation, for example, e-05 represents 10. -5 .

[0059] Table 1 Face number Surface type radius of curvature / mm Center thickness / mm Refractive index Abbe number OBJ S1 aspherical -890.24 5.40 1.51 56.60 S2 aspherical 154.78 13.98 S3 spherical 154.62 2.50 1.83 37.34 S4 spherical 43.93 8.54 S5 spherical 148.72 1.70 1.69 54.75 S6 spherical 33.04 D1 S7 spherical -38.32 2.00 1.50 81.61 S8 spherical 78.89 13.38 S9 spherical 928.85 5.50 2.00 25.46 S10 spherical -87.83 D2 S11 spherical 68.87 8.90 1.74 32.33 S12 spherical -73.47 2.50 1.85 23.78 S13 spherical -290.59 D3 S14 spherical 50.91 5.05 1.58 40.75 S15 spherical 4071.14 D4 S16 spherical INF 1.84 STO aspherical -61.57 4.15 1.59 61.25 S18 aspherical -44.73 0.31 S19 spherical -890.60 2.00 1.85 23.78 S20 spherical 24.65 10.42 1.49 70.45 S21 spherical -15.60 2.00 1.85 25.15 S22 spherical -161.18 3.51 S23 spherical -118.32 6.03 1.52 64.20 S24 spherical -27.71 2.86 S25 spherical -70.13 4.42 1.49 70.45 S26 spherical -34.24 D5 S27 spherical 67.03 5.54 1.95 17.98 S28 spherical -226.81 11.16 S29 spherical INF 28.96 1.52 64.20 S30 spherical INF 0.10 IMG Table 2 WIDE TELE D1 18.88 15.56 D2 19.5 8.99 D3 31.62 31.95 D4 5.71 9.87 D5 5.32 14.66 Table 3 Quadratic surface constant (K) 4th order coefficients (A) 6th order coefficients (B) 8th order coefficients (C) 10th-order coefficients (D) S1 0.00E+00 7.47E-06 -4.35E-09 1.73E-12 -4.15E-16 S2 3.78E+00 5.43E-06 -1.25E-09 -4.69E-12 4.81E-15 STO 0.00E+00 -4.92E-06 -6.33E-09 -5.94E-11 -7.95E-14 S18 0.00E+00 -1.83E-06 -1.93E-08 -7.11E-11 -4.37E-14 In this embodiment, fw=11.5mm, ft=14.2mm, ft / fw=1.23, TTL=233.78mm; fno=1.56~1.67; Wherein, fno is the aperture number of the zoom projection lens, ft is the focal length of the zoom projection lens in telephoto mode, fw is the focal length of the zoom projection lens in wide-angle mode, and TTL is the total optical length of the zoom projection lens.

[0060] fG5=88.17mm, fG5 / fw=7.67; fG6=-14082mm, fG6 / fw=-1224.5; Wherein, fG5 is the focal length of the third zoom lens group G5, and fG6 is the focal length of the fourth zoom lens group G6.

[0061] XG4=13.83mm, XG4 / fw=1.2; Wherein, XG4 is the maximum moving distance of the second zoom lens group G4.

[0062] XG3=3.32mm, XG3 / XG4=0.24; XG6=9.34mm, XG6 / XG4=0.68; Wherein, XG3 is the maximum moving distance of the first zoom lens group G3, and XG6 is the maximum moving distance of the fourth zoom lens group G6.

[0063] Φa1=91.32mm, Φb1=49.43mm, Φa1 / Φb1=1.85; Wherein, Φa1 is the outer diameter of the first focusing lens a1, and Φb1 is the outer diameter of the first fixed lens b1. Example 3

[0064] like Figures 6 to 10 As shown, a zoom projection lens is composed of, from the object plane side to the image plane side, a focusing lens group G1 with negative optical power, a first fixed lens group G2 with negative optical power, a first zoom lens group G3 with negative optical power, a second zoom lens group G4 with positive optical power, a third zoom lens group G5 with positive optical power, a fourth zoom lens group G6 with positive optical power, a second fixed lens group G7 with positive optical power, and an auxiliary component G8. The first zoom lens group G3, the second zoom lens group G4, the third zoom lens group G5, and the fourth zoom lens group G6 move along the main optical axis of the zoom projection lens. The focusing lens group G1 consists of a first focusing lens a1 with negative optical power and a second focusing lens a2 with negative optical power, from the object plane side to the image plane side. The first fixed lens group G2 is a first fixed lens b1 with negative optical power; The first zoom lens group G3 consists of a first zoom lens c1 with negative optical power and a second zoom lens c2 with positive optical power, from the object plane side to the image plane side. The second zoom lens group G4 is composed of a third zoom lens c3 with positive optical power and a fourth zoom lens c4 with negative optical power, from the object plane side to the image plane side, and the third zoom lens c3 and the fourth zoom lens c4 are cemented together. The third zoom lens group G5 is a fifth zoom lens c5 with positive optical power.

[0065] The fourth zoom lens group G6 consists of, from the object plane side to the image plane side, a sixth zoom lens c6 with negative optical power, a seventh zoom lens c7 with positive optical power, an eighth zoom lens c8 with negative optical power, a ninth zoom lens c9 with positive optical power, a tenth zoom lens c10 with negative optical power, and an eleventh zoom lens c11 with positive optical power. The eighth zoom lens c8, the ninth zoom lens c9, and the tenth zoom lens c10 together form a cemented triplet lens.

[0066] The second fixed lens group G7 is a second fixed lens b2 with positive optical power; The auxiliary component G8 is a beam splitter P.

[0067] The basic lens data of the zoom projection lens in this embodiment is shown in Table 4, the variable parameters in Table 4 are shown in Table 5, and the aspherical coefficients are shown in Table 6.

[0068] The surface number column shows the surface number when the object-side surface is set as surface 1 and the numbering is increased sequentially towards the image side; the surface type column shows the surface type of a lens; the radius of curvature column shows the radius of curvature of a lens, where a positive radius of curvature indicates that the surface is curved towards the object side and a negative radius of curvature indicates that the surface is curved towards the image side; the center thickness column shows the surface spacing on the optical axis between each surface and the surface adjacent to it on the image side; the refractive index column shows the refractive index of a lens; and the Abbe number column shows the Abbe number of a lens.

[0069] In Table 5, the WIDE column indicates the specific values ​​of each variable parameter when the zoom projection lens is in the wide-angle end state, and the TELE column indicates the specific values ​​of each variable parameter when the zoom projection lens is in the telephoto end state.

[0070] In Table 6, K is the conic coefficient, and e is the scientific notation, for example, e-05 represents 10. -5 .

[0071] Table 4 Face number Surface type radius of curvature / mm Center thickness / mm Refractive index Abbe number OBJ S1 aspherical 301.54 5.40 1.51 56.60 S2 aspherical 75.55 16.97 S3 spherical 1231.23 2.50 1.80 46.50 S4 spherical 57.88 8.45 S5 spherical 61.80 1.70 1.62 63.40 S6 spherical 25.18 D1 S7 spherical -45.27 2.00 1.50 81.61 S8 spherical 62.12 17.83 S9 spherical 215.63 5.00 1.85 23.78 S10 spherical -102.12 D2 S11 spherical 48.36 10.75 1.49 70.45 S12 spherical -55.04 1.80 1.69 31.16 S13 spherical -90.40 D3 S14 aspherical 27.47 6.84 1.69 53.20 S15 aspherical 25.37 D4 S16 spherical -31.39 1.50 1.69 31.16 STO spherical -71.49 4.07 S18 spherical 32.48 8.73 1.49 70.45 S19 spherical -50.26 1.00 S20 spherical -53.09 1.00 1.81 33.27 S21 spherical 23.07 13.15 1.50 81.61 S22 spherical -17.61 1.00 1.83 37.34 S23 spherical -67.18 1.51 S24 aspherical 67.75 11.28 1.50 81.56 S25 aspherical -28.02 D5 S26 spherical 60.99 4.95 1.95 17.98 S27 spherical 505.99 10.54 S28 spherical INF 28.96 1.52 64.20 S29 spherical INF 0.80 IMG Table 5 WIDE TELE D1 17.51 16.47 D2 28.84 9.83 D3 0.5 19.34 D4 12.87 3.8 D5 1.2 11.48 Table 6 Quadratic surface constant (K) 4th order coefficients (A) 6th order coefficients (B) 8th order coefficients (C) 10th-order coefficients (D) S1 0.00E+00 6.05E-06 -4.54E-09 2.56E-12 -8.53E-16 S2 -1.75E+01 8.89E-06 -9.02E-09 4.35E-12 -1.11E-15 S14 -3.06E-01 2.65E-06 4.45E-09 1.20E-11 1.73E-14 S15 2.13E-01 -4.49E-07 -1.40E-09 7.31E-11 -3.34E-13 S24 -1.65E+00 -5.57E-06 7.08E-09 -1.46E-11 4.02E-14 S25 -3.30E-01 6.28E-07 3.19E-10 -5.26E-12 2.02E-14 In this embodiment, fw=11.3mm, ft=14.2mm, ft / fw=1.26, TTL=228.65mm; fno=1.56~1.69; Wherein, fno is the aperture number of the zoom projection lens, ft is the focal length of the zoom projection lens in telephoto mode, fw is the focal length of the zoom projection lens in wide-angle mode, and TTL is the total optical length of the zoom projection lens.

[0072] fG5=1406.05mm, fG5 / fw=124.4; fG6 = 107.29 mm, fG6 / fw = 9.49; Wherein, fG5 is the focal length of the third zoom lens group G5, and fG6 is the focal length of the fourth zoom lens group G6.

[0073] XG4=20.05mm, XG4 / fw=1.77; Wherein, XG4 is the maximum moving distance of the second zoom lens group G4.

[0074] XG3=1.04mm, XG3 / XG4=0.05; XG6=10.28mm, XG6 / XG4=0.51; Wherein, XG3 is the maximum moving distance of the first zoom lens group G3, and XG6 is the maximum moving distance of the fourth zoom lens group G6.

[0075] Φa1=90.2mm, Φb1=46.41mm, Φa1 / Φb1=1.94; Wherein, Φa1 is the outer diameter of the first focusing lens a1, and Φb1 is the outer diameter of the first fixed lens b1. Example 4

[0076] An imaging device, such as Figures 1 to 10 As shown, it includes: a zoom projection lens as described in any of the above embodiments, and an imaging element configured to receive an image formed by the zoom projection lens.

[0077] It should be noted that the above embodiments can be freely combined as needed. The above description is only a preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A zoom projection lens, characterized in that, The zoom projection lens consists of, from the object plane side to the image plane side, a focusing lens group with negative optical power, a first fixed lens group with negative optical power, a first zoom lens group with negative optical power, a second zoom lens group with positive optical power, a third zoom lens group with positive optical power, a fourth zoom lens group, and a second fixed lens group with positive optical power. The first zoom lens group, the second zoom lens group, the third zoom lens group, and the fourth zoom lens group move along the main optical axis of the zoom projection lens; The focusing lens group consists of a first focusing lens with negative optical power and a second focusing lens with negative optical power, sequentially from the object plane side to the image plane side. The first fixed lens group is a first fixed lens with negative optical power; The second fixed lens group is a second fixed lens with positive optical power; The zoom projection lens satisfies the following condition: fno < 1.7; ft / fw < 2; Wherein, fno is the aperture number of the zoom projection lens, ft is the focal length of the zoom projection lens in telephoto mode, and fw is the focal length of the zoom projection lens in wide-angle mode.

2. A zoom projection lens according to claim 1, characterized in that: The first zoom lens group consists of a first zoom lens with negative optical power and a second zoom lens with positive optical power, sequentially from the object plane side to the image plane side. The second zoom lens group consists of a third zoom lens with positive optical power and a fourth zoom lens with negative optical power, arranged sequentially from the object plane side to the image plane side, and the third zoom lens and the fourth zoom lens are cemented together. The third zoom lens group is a fifth zoom lens with positive optical power.

3. A zoom projection lens according to claim 1, characterized in that: The first to fourth zoom lens groups each contain at least one aspherical lens.

4. A zoom projection lens according to claim 1, characterized in that: The fourth zoom lens group consists of, from the object plane side to the image plane side, a sixth zoom lens with negative optical power, a seventh zoom lens with positive optical power, an eighth zoom lens with negative optical power, a ninth zoom lens with positive optical power, a tenth zoom lens with negative optical power, and an eleventh zoom lens with positive optical power. The eighth, ninth, and tenth zoom lenses together form a cemented triplet lens.

5. A zoom projection lens according to claim 1, characterized in that: The fourth zoom lens group consists of a seventh zoom lens with positive optical power, an eighth zoom lens with negative optical power, a ninth zoom lens with positive optical power, a tenth zoom lens with negative optical power, an eleventh zoom lens with positive optical power, and a twelfth zoom lens with positive optical power, arranged sequentially from the object plane side to the image plane side. The eighth, ninth, and tenth zoom lenses together form a cemented triplet lens.

6. A zoom projection lens according to claim 4, characterized in that: The zoom projection lens satisfies the following condition: fG5 / fw < 10; fG6 / fw < -1000; Wherein, fG5 is the focal length of the third zoom lens group, and fG6 is the focal length of the fourth zoom lens group.

7. A zoom projection lens according to claim 5, characterized in that: The zoom projection lens satisfies the following condition: fG5 / fw > 124; fG6 / fw < 10; Wherein, fG5 is the focal length of the third zoom lens group, and fG6 is the focal length of the fourth zoom lens group.

8. A zoom projection lens according to claim 1, characterized in that: The first to fourth zoom lens groups move in the same direction.

9. A zoom projection lens according to claim 1, characterized in that: The zoom projection lens satisfies the following condition: 1 < XG4 / fw < 2; Wherein, XG4 is the maximum moving distance of the second zoom lens group, and XG5 is the maximum moving distance of the third zoom lens group.

10. A zoom projection lens according to claim 1, characterized in that: The zoom projection lens satisfies the following condition: XG3 / XG4 < 0.3; XG6 / XG4 < 0.7; Wherein, XG3 is the maximum moving distance of the first zoom lens group, and XG6 is the maximum moving distance of the fourth zoom lens group.

11. A zoom projection lens according to claim 1, characterized in that: The first focusing lens is an aspherical lens; The zoom projection lens satisfies the following condition: Φa1 / Φb1>1.8; Wherein, Φa1 is the outer diameter of the first focusing lens, and Φb1 is the outer diameter of the first fixed lens.

12. An imaging device, characterized in that, include: The zoom projection lens as described in any one of claims 1 to 11; An imaging element is configured to receive an image formed by the zoom projection lens.

Images