Projection lens and large-target-surface zoom projection system

Abstract

The utility model discloses a projection lens and a large target surface zoom projection system, and relates to the optical system technology field, the projection lens comprises a lens main body, the lens main body comprises a plurality of lens groups which are successively arranged from an object side to an image side, and an optical axis is correspondingly formed among the plurality of lens groups. The plurality of lens groups comprise a first lens group with negative focal power, a second lens group with negative focal power, a third lens group with positive focal power, a fourth lens group with positive focal power, a fifth lens group with negative focal power, a sixth lens group with positive focal power and a seventh lens group with positive focal power; the first lens group, the second lens group, the third lens group, the fourth lens group, the fifth lens group and the sixth lens group are movably arranged along the optical axis. According to the projection lens and the large-target-surface zoom projection system, the back focal length is long and larger than 55 m, the universality is good, the supported resolution is high, and the requirement for the resolution of 93 lp / mm is met.

Description

Technical Field

[0001] The utility model relates to the technical field of optical systems, and particularly relates to a projection lens and a large-target surface zoom projection system. Background Art

[0002] High-brightness engineering projectors have a large projection area and high brightness, and can be used in large and variable environments. Especially, they have unique advantages in teaching and business presentations. The brightness of engineering projectors is very important. Most of the projector lenses on the market have a small target surface, which limits the size of the display chips used in projectors, and the brightness output is mostly below 20,000 lm. At the same time, the back focal lengths of the lenses of engineering projectors vary. At this time, a longer back focal length is required for the lens to meet the requirements of projector lenses from different manufacturers. Based on the above, this utility model is proposed. Summary of the Utility Model

[0003] The main purpose of the utility model is to propose a projection lens and a large-target surface zoom projection system, aiming to at least solve the technical problems that the existing engineering projectors have a small target surface and a short back focal length, making it difficult to achieve high brightness and having poor versatility at the same time.

[0004] To achieve the above purpose, a projection lens proposed by the utility model includes a lens body. The lens body includes a plurality of lens groups arranged in sequence from the object side to the image side. An optical axis is correspondingly formed between the plurality of lens groups. The plurality of lens groups include a first lens group with a negative optical power, a second lens group with a negative optical power, a third lens group with a positive optical power, a fourth lens group with a positive optical power, a fifth lens group with a negative optical power, a sixth lens group with a positive optical power, and a seventh lens group with a positive optical power;

[0005] The first lens group, the second lens group, the third lens group, the fourth lens group, the fifth lens group, and the sixth lens group are movably arranged along the optical axis;

[0006] Wherein, the focal length of the projection lens is f, the focal length of the first lens group is f1, the focal length of the second lens group is f2, the focal length of the third lens group is f3, the focal length of the fourth lens group is f4, the focal length of the fifth lens group is f5, the focal length of the sixth lens group is f6, and the focal length of the seventh lens group is f7, satisfying the following relational expressions:

[0007] 2.5 < |f1 / f| < 3.0, 4 < |f2 / f| < 5, 2 < |f3 / f| < 3, 2.5 < |f4 / f| < 3.5, 13 < |f5 / f| < 16, 4 < |f6 / f| < 6, 4 < |f7 / f| < 6.

[0008] In one embodiment, the first lens group is a focusing structure, and the second lens group, the third lens group, the fourth lens group, the fifth lens group, and the sixth lens group are linkage structures.

[0009] In one embodiment, the first lens group includes a first lens with positive optical power, a second lens with positive optical power, a third lens with negative optical power, and a fourth lens with negative optical power, which are arranged in sequence from the object side to the image side;

[0010] The second lens group includes a fifth lens with positive optical power and a sixth lens with negative optical power, which are arranged in sequence from the object side to the image side;

[0011] The third lens group includes a seventh lens with positive optical power;

[0012] The fourth lens group includes an eighth lens with positive optical power;

[0013] The fifth lens group includes a ninth lens with negative optical power and a tenth lens with positive optical power, which are arranged in sequence from the object side to the image side;

[0014] The sixth lens group includes an eleventh lens with negative optical power, a twelfth lens with negative optical power, a thirteenth lens with negative optical power, a fourteenth lens with positive optical power, and a fifteenth lens with positive optical power, which are arranged in sequence from the object side to the image side;

[0015] The seventh lens group includes a sixteenth lens with positive optical power, which is arranged from the object side to the image side.

[0016] In one embodiment, the fifth lens and the sixth lens are arranged as a doublet lens;

[0017] The ninth lens and the tenth lens are arranged as a doublet lens;

[0018] The twelfth lens and the thirteenth lens are arranged as a doublet lens.

[0019] In one embodiment, the optical power of the first lens is φ 1 , the optical power of the second lens is φ 2 , the optical power of the third lens is φ 3 , the optical power of the fourth lens is φ 4 , and they satisfy the following relational expressions:

[0020] 0.001 < |φ 1 | < 0.007, 0.001 < |φ 2 | < 0.007, 0.005 < |φ 3 | < 0.01, 0.015 < |φ4 |<0.025;

[0021] The sum of the optical powers of the fifth lens and the sixth lens is φ 56 , and satisfies the following relational expression:

[0022] 0.005 < |φ 56 |<0.01;

[0023] The optical power of the seventh lens is φ 7 , and satisfies the following relational expression:

[0024] 0.01 < |φ 7 |<0.02;

[0025] The optical power of the eighth lens is φ 8 , and satisfies the following relational expression:

[0026] 0.01 < |φ 8 |<0.02;

[0027] The sum of the optical powers of the ninth lens and the tenth lens is φ 910 , and satisfies the following relational expression:

[0028] 0.001 < |φ 910 |<0.005;

[0029] The optical power of the eleventh lens is φ 11 , the sum of the optical powers of the twelfth lens and the thirteenth lens is φ 1213 , the optical power of the fourteenth lens φ 14 , the optical power of the fifteenth lens φ 15 , and satisfies the following relational expression:

[0030] 0.002 < |φ 11 |<0.007, 0.01 < |φ 1213 |<0.02, 0.05 < |φ 14 |<0.01, 0.01 < |φ 15 |<0.02;

[0031] The optical power of the sixteenth lens is φ 16 , and satisfies the following relational expression:

[0032] 0.005 < |φ 16 |<0.01.

[0033] In one embodiment, the first lens is a convex-concave lens, and its object side is a convex surface;

[0034] The second lens is a convex-concave lens, and its object side is a convex surface;

[0035] The third lens is a convex-concave lens, and its object side is convex;

[0036] The fourth lens is a convex-concave lens, and its object side is convex;

[0037] The fifth lens is a concave-convex lens, and its object side is concave;

[0038] The sixth lens is a biconcave lens, and its object side is concave;

[0039] The seventh lens is a biconvex lens, and its object side is convex;

[0040] The eighth lens is a biconvex lens, and its object side is convex;

[0041] The ninth lens is a biconcave lens, and its object side is concave;

[0042] The eighth lens is a biconvex lens, and its object side is convex;

[0043] The eleventh lens is a convex-concave lens, and its object side is convex;

[0044] The twelfth lens is a biconcave lens, and its object side is concave;

[0045] The thirteenth lens is a biconvex lens, and its object side is convex;

[0046] The fourteenth lens is a biconvex lens, and its object side is convex;

[0047] The fifteenth lens is a biconvex lens, and its object side is convex;

[0048] The sixteenth lens is a convex-concave lens, and its object side is convex.

[0049] In one embodiment, the first lens to the sixteenth lens are all provided as glass spherical lenses.

[0050] In one embodiment, the projection lens further includes a diaphragm, an equivalent prism, a protective glass, and a display chip;

[0051] The diaphragm is disposed between the third lens group and the fourth lens group, and the equivalent prism, the protective glass, and the display chip are sequentially disposed on the image side of the seventh lens group along the optical axis.

[0052] In one embodiment, the overall optical length of the projection lens is TTL, and the specific distance from the image side of the seventh lens group to the display chip is BFL, satisfying the following relationship:

[0053] TTL / BFL ≤ 3.6, and BFL is greater than 55 mm.

[0054] The present utility model also provides a large target surface zoom projection system. The large target surface zoom projection system includes a projection lens. The projection lens includes a lens body. The lens body includes a plurality of lens groups arranged in sequence from the object side to the image side. An optical axis is correspondingly formed between the plurality of lens groups. The plurality of lens groups include a first lens group with a negative optical power, a second lens group with a negative optical power, a third lens group with a positive optical power, a fourth lens group with a positive optical power, a fifth lens group with a negative optical power, a sixth lens group with a positive optical power, and a seventh lens group with a positive optical power;

[0055] The first lens group, the second lens group, the third lens group, the fourth lens group, the fifth lens group, and the sixth lens group are movably arranged along the optical axis;

[0056] Wherein, the focal length of the projection lens is f, the focal length of the first lens group is f1, the focal length of the second lens group is f2, the focal length of the third lens group is f3, the focal length of the fourth lens group is f4, the focal length of the fifth lens group is f5, the focal length of the sixth lens group is f6, and the focal length of the seventh lens group is f7, satisfying the following relational expressions:

[0057] 2.5 < |f1 / f| < 3.0, 4 < |f2 / f| < 5, 2 < |f3 / f| < 3, 2.5 < |f4 / f| < 3.5, 13 < |f5 / f| < 16, 4 < |f6 / f| < 6, 4 < |f7 / f| < 6.

[0058] In the technical solution of the present utility model, the disclosed lens structure includes seven lens groups. The focal length of the projection lens and the focal length of each lens group satisfy the following relationships: 2.5 < |f1 / f| < 3.0, 4 < |f2 / f| < 5, 2 < |f3 / f| < 3, 2.5 < |f4 / f| < 3.5, 13 < |f5 / f| < 16, 4 < |f6 / f| < 6, 4 < |f7 / f| < 6. On this basis, the first lens group, the second lens group, the third lens group, the fourth lens group, the fifth lens group, and the sixth lens group can move back and forth relative to the display chip. The seventh lens group is immovable relative to the display chip. The forward and backward movement of the first lens group can meet the performance requirements of different projection distances. The second lens group, the third lens group, the fourth lens group, the fifth lens group, and the sixth lens group are linked to achieve a large zoom ratio, and the back focal length is long, greater than 55m, with good versatility; the image-side target surface is large, and it can support a 0.8-inch DMD chip, and the offset supports up to 120%; and it supports a high resolution, meeting the resolution requirement of 93 lp / mm. Description of the Drawings

[0059] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0060] Figure 1 Structural diagrams of each part of an embodiment of the projection lens provided by the present invention at the shortest focal length;

[0061] Figure 2 For Figure 1 Structural diagrams of each part of the projection lens at the longest focal length in

[0062] Figure 3 For Figure 1 MTF curve graph of the projection lens at the shortest focal length in

[0063] Figure 4 For Figure 1 Field curvature and distortion performance curve graph of the projection lens at the shortest focal length in

[0064] Figure 5 For Figure 1 MTF curve graph of the projection lens at the longest focal length in

[0065] Figure 6 For Figure 1 Field curvature and distortion performance curve graph of the projection lens at the longest focal length in

[0066] Explanation of the reference numerals in the drawings:

[0067] 100, projection lens; 10, first lens group; 1, first lens; 2, second lens; 3, third lens; 4, fourth lens; 20, second lens group; 5, fifth lens; 6, sixth lens; 30, third lens group; 7, seventh lens; 40, fourth lens group; 8, eighth lens; 50, third lens group; 9, ninth lens; 10, tenth lens; 60, sixth lens group; 11, eleventh lens; 12, twelfth lens; 13, thirteenth lens; 14, fourteenth lens; 15, fifteenth lens; 70, seventh lens group; 16, sixteenth lens; 17, aperture stop; 171, equivalent prism; 172, protective glass; 173, display chip.

[0068] The realization, functional features and advantages of the object of the present invention will be further described in conjunction with the embodiments and with reference to the accompanying drawings. Detailed implementation manners

[0069] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.

[0070] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0071] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution that satisfies both A and B at the same time. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0072] The high-brightness engineering projector has a large projection area and high brightness, and can be used in large and variable environments. Especially in teaching and business presentations, it has unique advantages. The brightness of the engineering projector is very important. Most of the target surfaces of the projector lenses on the market are relatively small, which limits the size of the display chip 173 used in the projector, and the brightness output is mostly below 20,000 lm. At the same time, the back focal lengths of the lenses of the engineering projector are different. At this time, a longer back focal length of the lens is required to meet the needs of projector lenses from different manufacturers. Based on the above, this utility model is proposed.

[0073] The present utility model provides a projection lens and a large-target surface zoom projection system, aiming to at least solve the technical problems that the existing engineering projectors have a small target surface and a short back focal length, making it difficult to achieve high brightness and having poor versatility at the same time.

[0074] Please refer to Figure 1, in an embodiment of the present utility model, it includes a lens body. The lens body includes a plurality of lens groups arranged in sequence from the object side to the image side. A optical axis is correspondingly formed between the plurality of lens groups. The plurality of lens groups include a first lens group 10 with a negative focal power, a second lens group 20 with a negative focal power, a third lens group 30 with a positive focal power, a fourth lens group 40 with a positive focal power, a fifth lens group 50 with a negative focal power, a sixth lens group 60 with a positive focal power, and a seventh lens group 70 with a positive focal power. And the focal lengths between the projection lens 100 and the plurality of lens groups satisfy the following relationship: the focal length of the Wide end of the projection lens 100 is f, the focal length of the first lens group 10 is f1, the focal length of the second lens group 20 is f2, the focal length of the third lens group 30 is f3, the focal length of the fourth lens group 40 is f4, the focal length of the fifth lens group 50 is f5, the focal length of the sixth lens group 60 is f6, and the focal length of the seventh lens group 70 is f7. Then it satisfies 2.5 < |f1 / f| < 3.0, 4 < |f2 / f| < 5, 2 < |f3 / f| < 3, 2.5 < |f4 / f| < 3.5, 13 < |f5 / f| < 16, 4 < |f6 / f| < 6, 4 < |f7 / f| < 6. The lens groups are arranged according to this focal length to form a retrofocus structure, achieving a smaller overall length and having a longer back focal length. Among them, the first lens group 10, the second lens group 20, the third lens group 30, the fourth lens group 40, the fifth lens group 50, and the sixth lens group 60 are movably arranged along the optical axis to satisfy the active focusing of the lens body and meet the performance requirements of different projection distances.

[0075] Specifically, in order to further achieve a larger zoom ratio, in this embodiment, the first lens group 10 is a focusing structure, which realizes focusing through independent movement. And the second lens group 20, the third lens group 30, the fourth lens group 40, the fifth lens group 50, and the sixth lens group 60 are set as a linkage structure. By adjusting one of the above-mentioned lens groups, it can drive a plurality of lenses connected thereto to perform synchronous movement along the optical axis direction, so that the entire projection lens 100 has a larger zoom ratio and is also more convenient to operate.

[0076] And in the above several embodiments, by setting the first lens group 10 to have a negative optical power, where the first lens 1 has a positive optical power, distortion can be effectively corrected; the second lens group 20 is set to have a negative optical power, the third lens group 30 is set to have a positive optical power, the fourth lens group 40 is set to have a positive optical power, the fifth lens 5 is set to have a negative optical power, the sixth lens group 60 is set to have a positive optical power, and the second lens group 20 to the sixth lens group 60 are linked to ensure that the image plane position remains unchanged during the zooming process, and a zoom ratio of ≥1.49 times can be achieved. The seventh lens group 70 is set to have a positive optical power, which can be used to converge the remaining aberrations of the system, realize a telecentric optical system, enable the system to obtain a larger target surface, and at the same time have a higher imaging quality.

[0077] Specifically, among the seven lens groups included in the projection lens 100, they respectively have the following lens compositions: the first lens group 10 includes a first lens 1 with a positive optical power, a second lens 2 with a positive optical power, a third lens 3 with a negative optical power, and a fourth lens 4 with a negative optical power arranged in sequence from the object side to the image side; the second lens group 20 includes a fifth lens 5 with a positive optical power and a sixth lens 6 with a negative optical power arranged in sequence from the object side to the image side; the third lens group 30 includes a seventh lens 7 with a positive optical power; the fourth lens group 40 includes an eighth lens 8 with a positive optical power; the fifth lens group 50 includes a ninth lens 9 with a negative optical power and a tenth lens 10 with a positive optical power arranged in sequence from the object side to the image side; the sixth lens group 60 includes an eleventh lens 11 with a negative optical power, a twelfth lens 12 with a negative optical power, a thirteenth lens 13 with a negative optical power, a fourteenth lens 14 with a positive optical power, and a fifteenth lens 15 with a positive optical power arranged in sequence from the object side to the image side; the seventh lens group 70 includes a sixteenth lens 16 with a positive optical power arranged from the object side to the image side.

[0078] Among the lens combinations of the above multiple lens groups, in order to further improve the imaging quality of the entire projection lens 100 and reduce its overall size specification, multiple cemented lenses are provided in the specific lens settings. Specifically, the fifth lens 5 and the sixth lens 6 are set as doublet lenses to correct the magnification chromatic aberration, the ninth lens 9 and the tenth lens 10 are set as doublet lenses to correct the axial chromatic aberration, the twelfth lens 12 and the thirteenth lens 13 are set as doublet lenses to correct the high-order chromatic aberration and correct the aberration of a large aperture. By using three doublet lenses, the system can obtain a smaller chromatic aberration. The setting of multiple doublet lenses effectively improves the light transmission amount and enables the imaging to be clearer.

[0079] To achieve better imaging effects, in this embodiment, the optical powers of the above-mentioned multiple lenses are further limited. Specifically, the optical power of the first lens 1 is φ 1 and the optical power φ 2 of the second lens 2, the optical power φ 3 of the third lens 3, the optical power φ 4 of the fourth lens 4 satisfy the following relational expressions: 0.001 < |φ 1 | < 0.007, 0.001 < |φ 2 | < 0.007, 0.005 < |φ 3 | < 0.01, 0.015 < |φ 4 | < 0.025; the sum of the optical powers of the fifth lens 5 and the sixth lens 6 is φ 56 and satisfies the following relational expression: 0.005 < |φ 56 | < 0.01; the optical power of the seventh lens 7 is φ 7 and satisfies the following relational expression: 0.01 < |φ 7 | < 0.02; the optical power of the eighth lens 8 is φ 8 and satisfies the following relational expression: 0.01 < |φ 8 | < 0.02; the sum of the optical powers of the ninth lens 9 and the tenth lens 10 is φ 910 and satisfies the following relational expression: 0.001 < |φ 910 | < 0.005; the optical power of the eleventh lens 11 is φ 11 , the sum of the optical powers of the twelfth lens 12 and the thirteenth lens 13 is φ 1213 , the optical power φ 14 of the fourteenth lens 14, the optical power φ 15 of the fifteenth lens 15 satisfy the following relational expressions: 0.002 < |φ 11 | < 0.007, 0.01 < |φ 1213 | < 0.02, 0.05 < |φ 14 | < 0.01, 0.01 < |φ 15 | < 0.02; the optical power of the sixteenth lens 16 is φ 16 and satisfies the following relational expression: 0.005 < |φ 16 | < 0.01. According to the above optical power distribution, a higher resolution can be achieved.

[0080] Moreover, the specific structures of the first lens 1 to the sixteenth lens 16 are designed as follows. The first lens 1 is a convex-concave lens, and its object side is a convex surface; the second lens 2 is a convex-concave lens, and its object side is a convex surface; the third lens 3 is a convex-concave lens, and its object side is a convex surface; the fourth lens 4 is a convex-concave lens, and its object side is a convex surface; the fifth lens 5 is a concave-convex lens, and its object side is a concave surface; the sixth lens 6 is a bi-concave lens, and its object side is a concave surface; the seventh lens 7 is a bi-convex lens, and its object side is a convex surface; the eighth lens 8 is a bi-convex lens, and its object side is a convex surface; the ninth lens 9 is a bi-concave lens, and its object side is a concave surface; the tenth lens 10 is a bi-convex lens, and its object side is a convex surface; the eleventh lens 11 is a convex-concave lens, and its object side is a convex surface; the twelfth lens 12 is a bi-concave lens, and its object side is a concave surface; the thirteenth lens 13 is a bi-convex lens, and its object side is a convex surface; the fourteenth lens 14 is a bi-convex lens, and its object side is a convex surface; the fifteenth lens 15 is a bi-convex lens, and its object side is a convex surface; the sixteenth lens 16 is a convex-concave lens, and its object side is a convex surface.

[0081] Meanwhile, the first lens 1 to the sixteenth lens 16 are all designed as glass spherical lenses.

[0082] In order to improve the imaging quality of the projection lens 100, including brightness, resolution, etc., in this embodiment, a diaphragm 17 is provided between the third lens group 30 and the fourth lens group 40, and an equivalent prism 171, a protective glass 172, and a display chip 173 are sequentially provided along the optical axis on the image side of the seventh lens group 70. The equivalent prism 171 has a certain light filtering effect and can effectively improve the imaging effect. The display chip 173 is used to receive the object image from the object side. During this process, the protective glass 172 can protect the display chip 173.

[0083] It should be noted that the overall optical length of the projection lens 100 is TTL, and the specific distance from the image side of the seventh lens group 70 to the display chip 173 is BFL, which satisfies the following relationship: TTL / BFL ≤ 3.6, and BFL is greater than 55 mm. After such a setting, a longer back focal length can be achieved, which can meet the requirements of projector lenses from different manufacturers and realizes good versatility.

[0084] In this embodiment, the basic parameters of the projection lens 100 are shown in Tables 1 to 2.

[0085] Table 1:

[0086]

[0087]

[0088] The distance from the object side of the projection lens 100 to the first surface of the first lens 1 is defined as the projection distance. The variation range of the projection distance is from 2 m to 20 m. When the projection distance changes, the first lens group 10 moves back and forth for focusing, while the second lens group 20, the third lens group 30, the fourth lens group 40, the fifth lens group 50, and the sixth lens group 60 remain fixed. When the projection distance of the projection lens 100 is set to 5.315 m, the intervals that change between each lens group from the Wide (shortest focal length) end to the Tele (longest focal length) end are as shown in Table 2 below:

[0089] Table 2:

[0090] Surface number wide end Tele end 8 13.75 10.98 11 38.86 20.02 13 22.94 19.02 16 1.87 3.28 19 0.58 17.95 28 1 7.73

[0091] The present utility model also provides a large target surface zoom projection system. The large target surface zoom projection system includes a projection lens 100. The specific structure of the projection lens 100 refers to the above embodiments. Since the large target surface zoom projection system adopts all the technical solutions of the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here one by one.

[0092] The above description is only an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformation made under the technical concept of the present utility model by using the content of the specification and drawings of the present utility model, or any direct / indirect application in other related technical fields is included in the patent protection scope of the present utility model.

Claims

1. A projection lens, characterized in that: The lens body comprises a plurality of lens groups arranged in sequence from the object side to the image side, wherein an optical axis is formed between the plurality of lens groups, and the plurality of lens groups comprise a first lens group with negative optical power, a second lens group with negative optical power, a third lens group with positive optical power, a fourth lens group with positive optical power, a fifth lens group with negative optical power, a sixth lens group with positive optical power, and a seventh lens group with positive optical power; The first lens group, the second lens group, the third lens group, the fourth lens group, the fifth lens group and the sixth lens group are movably arranged along the optical axis; The focal length of the projection lens is f, the focal length of the first lens group is f1, the focal length of the second lens group is f2, the focal length of the third lens group is f3, the focal length of the fourth lens group is f4, the focal length of the fifth lens group is f5, the focal length of the sixth lens group is f6, and the focal length of the seventh lens group is f7, which satisfies the following relationship: 2.5<|f1 / f|<3.0, 4<|f2 / f|<5, 2<|f3 / f|<3, 2.5<|f4 / f|<3.5, 13<|f5 / f|<16, 4<|f6 / f|<6, 4<|f7 / f|<6.

2. The projection lens according to claim 1, wherein: The first lens group is a focusing structure, and the second lens group, the third lens group, the fourth lens group, the fifth lens group and the sixth lens group are a linkage structure.

3. The projection lens according to claim 2, wherein: The first lens group comprises a first lens with positive optical power, a second lens with positive optical power, a third lens with negative optical power, and a fourth lens with negative optical power, which are arranged in sequence from the object side to the image side; The second lens group includes a fifth lens with positive refractive power and a sixth lens with negative refractive power, which are arranged in sequence from the object side to the image side; The third lens group includes a seventh lens having positive refractive power; The fourth lens group includes an eighth lens having positive refractive power; The fifth lens group includes a ninth lens having negative optical power and a tenth lens having positive optical power, which are arranged in sequence from the object side to the image side; The sixth lens group includes an eleventh lens with negative power, a twelfth lens with negative power, a thirteenth lens with negative power, a fourteenth lens with positive power and a fifteenth lens with positive power, which are arranged in sequence from the object side to the image side; The seventh lens group includes a sixteenth lens having positive refractive power arranged from the object side to the image side.

4. The projection lens according to claim 3, wherein: The fifth lens and the sixth lens are configured as a doublet lens; The ninth lens and the tenth lens are configured as a doublet lens; The twelfth lens and the thirteenth lens are configured as a doublet lens.

5. The projection lens according to claim 3, wherein: The focal power of the first lens is φ1, the focal power of the second lens is φ2, the focal power of the third lens is φ3, and the focal power of the fourth lens is φ4, which satisfy the following relationship: 0.001<|φ1|<0.007, 0.001<|φ2|<0.007, 0.005<|φ3|<0.01, 0.015<|φ4|<0.025; The sum of the optical powers of the fifth lens and the sixth lens is φ 56 , satisfying the following relationship: 0.005<|φ 56 |<0.01; The focal power of the seventh lens is φ7, which satisfies the following relationship: 0.01<|φ7|<0.02; The optical power of the eighth lens is φ8, which satisfies the following relationship: 0.01<|φ8|<0.02; The sum of the focal power of the ninth lens and the focal power of the tenth lens is φ 910 , satisfying the following relationship: 0.001<|φ 910 |<0.005; The focal power of the eleventh lens is φ 11 The sum of the focal powers of the twelfth lens and the thirteenth lens is φ 1213 , the focal power φ of the fourteenth lens 14 , the focal power φ of the fifteenth lens 15 , satisfying the following relationship: 0.002<|φ 11 |<0.007、0.01<|φ 1213 |<0.02、0.05<|φ 14 |<0.01、0.01<|φ 15 |<0.02; The focal power of the sixteenth lens is φ 16 , satisfying the following relationship: 0.005<|φ 16 |<0.01。 6. The projection lens according to claim 3, wherein: The first lens is a convex-concave lens, and its object side surface is convex; The second lens is a convex-concave lens, and its object side surface is convex; The third lens is a convex-concave lens, and its object side surface is convex; The fourth lens is a convex-concave lens, and its object side surface is convex; The fifth lens is a meniscus lens, and its object side surface is concave; The sixth lens is a biconcave lens; The seventh lens is a biconvex lens; The eighth lens is a biconvex lens; The ninth lens is a biconcave lens; The tenth lens is a biconvex lens; The eleventh lens is a convex-concave lens, and its object side surface is a convex surface; The twelfth lens is a biconcave lens; The thirteenth lens is a biconvex lens; The fourteenth lens is a biconvex lens; The fifteenth lens is a biconvex lens; The sixteenth lens is a convex-concave lens, and its object-side surface is convex.

7. The projection lens according to claim 3, wherein: The first lens to the sixteenth lens are all configured as glass spherical lenses.

8. The projection lens according to claim 1, wherein: The projection lens also includes an aperture, an equivalent prism, a protective glass and a display chip; The aperture is arranged between the third lens group and the fourth lens group, and the equivalent prism a, the protection glass and the display chip are arranged in sequence on the image side of the seventh lens group along the optical axis.

9. The projection lens according to claim 8, wherein: The total optical length of the projection lens is TTL, and the distance from the image side of the seventh lens group to the display chip is BFL, which satisfies the following relationship: TTL / BFL≤3.6, and BFL is greater than 55mm.

10. A large-scale zoom projection system, characterized in that: The large-surface zoom projection system comprises the projection lens according to any one of claims 1 to 9.

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