Zoom lens and imaging device

Abstract

The present invention discloses a zoom lens and an imaging device, including a lens assembly and a driving device. The lens assembly includes a plurality of lens groups composed of a plurality of lenses. The driving device is drivingly connected to the plurality of lens groups. The plurality of lens groups are arranged along the optical axis direction of the zoom lens and sequentially include a first lens group with a positive 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 negative optical power, and a fifth lens group with a positive optical power from the object side to the image side. The plurality of lens groups are movably arranged in the optical axis extending direction. Zooming is achieved by the driving device to change the interval between adjacent lens groups and the interval between the fifth lens group and the image plane of the zoom lens. The maximum diameter of the lens assembly is d ≤ 45.6 mm, and the optical length of the zoom lens is L ≤ 110 mm. This solution limits the size and the total optical length of the lens assembly, and realizes a compact variable-focus lens through a plurality of lens groups.

Description

Technical Field

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

[0002] In recent years, with the further development of equipment in the security field, the demand for scene monitoring has become increasingly high. It is necessary to meet both the wide-field search in a large field of view and the precise observation in a small field of view. Therefore, the demand for compact, large-aperture, and low-cost zoom lenses has become increasingly large. Thus, the design and development of compact, large-aperture, and low-cost zoom lenses have become a necessity. Summary of the Invention

[0003] The main object of the present invention is to provide a zoom lens and a camera device, aiming to solve the technical problem that the size of existing lenses capable of zooming in a large range from a wide-angle wide field of view to a narrow field of view is too large.

[0004] To achieve the above object, a zoom lens provided by the present invention includes a lens assembly and a driving device. The lens assembly includes a plurality of lens groups composed of a plurality of lenses. The driving device is drivingly connected to the plurality of lens groups. The plurality of lens groups are arranged along the optical axis direction of the zoom lens, and sequentially include, from the object side to the image side: a first lens group having a positive optical power;

[0005] a second lens group having a negative optical power;

[0006] a third lens group having a positive optical power;

[0007] a fourth lens group having a negative optical power; and

[0008] a fifth lens group having a positive optical power;

[0009] Wherein, the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group are movably arranged in the optical axis extension direction. Zooming is achieved by changing the interval between adjacent lens groups and the interval between the fifth lens group and the image plane of the zoom lens through the driving device;

[0010] Wherein, assuming the maximum diameter of the lens assembly is d, d ≤ 45.6 mm, and assuming the distance from the end of the first lens group close to the object side to the image plane is L, L ≤ 110 mm.

[0011] Optionally, the following conditional expression is satisfied:

[0012] 17 ≤ Ft / Fw ≤ 18

[0013] Wherein, Ft represents the maximum focal length of the zoom lens, and Fw represents the minimum focal length of the zoom lens.

[0014] Optionally, let the focal length of the zoom lens be f, where 7 mm ≤ f ≤ 121 mm.

[0015] Optionally, let the F-number of the zoom lens be Fno, where 1 ≤ Fno ≤ 3.

[0016] Optionally, let the field of view angle of the zoom lens be ω, where 4.3° ≤ ω ≤ 38.8°.

[0017] Optionally, let the number of lenses in the first lens group be N1, where N1 ≤ 5; and / or,

[0018] let the number of lenses in the second lens group be N2, where N2 ≤ 4; and / or,

[0019] let the number of lenses in the third lens group be N3, where N3 ≤ 5; and / or,

[0020] let the number of lenses in the fourth lens group be N4, where N4 = 1; and / or,

[0021] let the number of lenses in the fifth lens group be N5, where N5 ≤ 2.

[0022] Optionally, in the order from the object side to the image side of the lens assembly, let the optical powers of the lenses closest to the object side in each lens group be θ1, θ2, θ3, θ4, and θ5 in sequence; where,

[0023] 0.00026 ≤ θ1 ≤ 0.00027;

[0024] -0.09 ≤ θ2 ≤ -0.07;

[0025] 0.036 ≤ θ3 ≤ 0.038;

[0026] -0.05 ≤ θ4 ≤ -0.03;

[0027] 0.03 ≤ θ5 ≤ 0.05.

[0028] Optionally, the first lens group is fixedly arranged, and the second lens group, the third lens group, the fourth lens group, and the fifth lens group are all movably arranged along the optical axis extension direction;

[0029] let the air spacing between the first lens group and the second lens group be D1, where 0.515 ≤ D1 ≤ 27.389;

[0030] let the air spacing between the second lens group and the third lens group be D2, where 0.577 ≤ D2 ≤ 36.048;

[0031] Let the air gap between the third lens group and the fourth lens group be D3, where 0.5 ≤ D3 ≤ 2.992;

[0032] Let the air gap between the fourth lens group and the fifth lens group be D4, where 0.276 ≤ D4 ≤ 11.907;

[0033] Let the air gap between the fifth lens group and the image plane be D5, where 3.955 ≤ D5 ≤ 16.362.

[0034] Optionally, all the lenses of the lens assembly are spherical lenses.

[0035] The present invention also provides an imaging device, which includes a zoom lens; and

[0036] an imaging element configured to receive light of an image formed by the zoom lens;

[0037] The zoom lens includes a lens assembly and a driving device. The lens assembly includes a plurality of lens groups composed of a plurality of lenses. The driving device is drivingly connected to the plurality of lens groups. The plurality of lens groups are arranged along the optical axis direction of the zoom lens and sequentially include, from the object side to the image side: a first lens group having a positive optical power;

[0038] a second lens group having a negative optical power;

[0039] a third lens group having a positive optical power;

[0040] a fourth lens group having a negative optical power; and

[0041] a fifth lens group having a positive optical power;

[0042] wherein, the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group are movably arranged in the optical axis extension direction, and zooming is achieved by changing the interval between adjacent lens groups and the interval between the fifth lens group and the image plane of the zoom lens through the driving device;

[0043] wherein, let the maximum diameter of the lens assembly be d, d ≤ 45.6 mm, and let the distance from the end of the first lens group close to the object side to the image plane be L, L ≤ 110 mm.

[0044] In the technical solution of the present invention, the zoom lens includes a lens assembly and a driving device. The lens assembly includes a plurality of lens groups composed of a plurality of lenses. The driving device is drivingly connected to the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group. The first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group are arranged along the optical axis direction of the zoom lens, and sequentially include a first lens group with positive optical power, a second lens group with negative optical power, a third lens group with positive optical power, a fourth lens group with negative optical power, and a fifth lens group with positive optical power from the object side to the image side. In this solution, the plurality of lens groups are movably arranged in the extending direction of the optical axis. By changing the interval between adjacent lens groups and the interval between the fifth lens group and the image plane of the zoom lens through the driving device, the focal length can be adjusted, so that the zoom lens can be applied to more scenarios. In this technical solution, the maximum diameter of the lens assembly is d, d ≤ 45.6 mm, and the distance from the end of the first lens close to the object side to the image plane is L, L ≤ 110 mm. By restricting the diameter of the largest lens in the lens assembly, the radial dimension of the zoom lens is controlled, and by restricting the overall optical length of the zoom lens, the axial dimension of the zoom lens is controlled, so that the size of the zoom lens does not exceed the limit on the premise of variable focal length, and a compact zoom lens is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0046] Figure 1 FIG. is a schematic structural diagram of an embodiment of the zoom lens provided by the present invention;

[0047] Figure 2 is Figure 1 schematic structural diagrams of various states during the zooming process of the zoom lens in;

[0048] Figure 3 is Figure 1 the field curvature diagram of the wide-angle end of the zoom lens in;

[0049] Figure 4 is Figure 1 the field curvature diagram of the middle position of the zoom lens in;

[0050] Figure 5 is Figure 1Field curvature diagram of the telephoto end of the medium zoom lens;

[0051] Figure 6 is Figure 1 Distortion diagram of the wide-angle end of the medium zoom lens;

[0052] Figure 7 is Figure 1 Distortion diagram of the middle position of the medium zoom lens;

[0053] Figure 8 is Figure 1 Distortion diagram of the telephoto end of the medium zoom lens;

[0054] Figure 9 is Figure 1 Spot diagram of the wide-angle end of the medium zoom lens;

[0055] Figure 10 is Figure 1 Spot diagram of the middle position of the medium zoom lens;

[0056] Figure 11 is Figure 1 Spot diagram of the telephoto end of the medium zoom lens.

[0057] Explanation of the reference numerals in the drawings:

[0058]

[0059] 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

[0060] 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 of 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 shall fall within the protection scope of the present invention.

[0061] 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, then the directional indications are only used to explain the relative positional relationship and movement conditions between the components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0062] 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 used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0063] In recent years, with the further development of equipment in the security field, the demand for scene monitoring has become higher and higher, which requires both the search in a wide field under a large field of view and the precise observation in a small field of view. The demand for compact, large aperture, low-cost zoom lenses has become increasingly greater. Therefore, the design and development of compact, large aperture, low-cost zoom lenses has become a demand.

[0064] In view of this, the present invention provides a zoom lens and a camera device to solve the technical problem that the conventional zoom lens capable of zooming in a wide range from wide angle and wide field of view to narrow field of view is too large in size. Figures 1 to 4 This is an embodiment of the zoom lens provided by the present invention.

[0065] In the present invention, the zoom lens comprises a lens barrel (not shown in the figure), a lens assembly and a driving device (not shown in the figure), the lens barrel extends along the optical axis direction of the zoom lens, the lens assembly is installed in the lens barrel, the lens assembly comprises a plurality of lens groups composed of a plurality of lenses, the driving device drives and connects the plurality of lens groups to drive the plurality of lens groups to move; the plurality of lens groups are arranged along the optical axis direction of the zoom lens, and sequentially comprise from the object side to the image side: a first lens group 100 having a positive optical power; a second lens group 20 having a negative optical power; 0; a third lens group 300 with positive optical power; a fourth lens group 400 with negative optical power; a fifth lens group 500 with positive optical power; the plurality of lens groups are movably arranged in the extension direction of the optical axis, and zooming is achieved by changing the intervals between adjacent lens groups and the interval between the fifth lens group 500 and the image plane 600 of the zoom lens through the driving device; wherein, the maximum diameter of the lens assembly is d, d≤45.6mm, and the distance from the end of the first lens group 100 close to the object side to the image plane 600 is L, L≤110mm.

[0066] In the technical solution of the present invention, the zoom lens includes a driving assembly, a lens barrel, and a lens assembly disposed in the lens barrel. The lens barrel extends along the optical axis direction of the zoom lens. The lens assembly includes a plurality of lens groups composed of a plurality of lenses. The plurality of lens groups are movably arranged in the extending direction of the optical axis. The driving device is drivingly connected to the plurality of lens groups to drive the plurality of lens groups to move, so as to change the interval between adjacent lens groups and the interval between the fifth lens group 500 and the image plane 600 of the zoom lens to achieve zooming. In this solution, the driving device is respectively drivingly connected to the second lens group 200, the third lens group 300, the fourth lens group 400, and the fifth lens group 500; the first lens group 100 is fixedly arranged in the lens barrel and is a front fixed group; the second lens group 200 and the third lens group 300 are movably arranged in the extending direction of the optical axis and form a zoom lens group; the fourth lens group 400 and the fifth lens group 500 are movably arranged in the extending direction of the optical axis and form a compensation lens group; the variable magnification lens group mainly undertakes the variable magnification function and can realize continuous zooming of the lens body from the wide-angle end to the telephoto end; the compensation lens group mainly undertakes the image plane 600 compensation function and can compensate the image plane 600 during the continuous zooming process of the zoom lens, so as to ensure the imaging quality when the zoom lens continuously zooms. Further, in this solution, let the maximum diameter of the lens assembly be d, that is, the diameter of the largest lens in the lens assembly is d, d≤45.6mm, and let the distance from the end of the first lens group 100 close to the object side to the image plane 600 be L, that is, the total optical length of the zoom lens is L, L≤110mm; which is equivalent to limiting the maximum inner diameter and the maximum length of the lens barrel. Therefore, under the cooperation of the zoom lens group and the compensation lens group, not only can a large-range zoom from a wide-angle wide field of view to a narrow field of view be realized, but also the imaging within this focal length range can be ensured to be clear. Furthermore, the volume of the lens can be reduced, the total optical length and the radial dimension of the zoom lens can be shortened, and a compact zoom lens can be realized.

[0067] In an embodiment of the present invention, the zoom lens satisfies the following conditional expression: 17≤Ft / Fw≤18, where Ft represents the maximum focal length of the zoom lens, and Fw represents the minimum focal length of the zoom lens.

[0068] Based on the above parameters, when each of the second lens group 200, the third lens group 300, the fourth lens group 400, and the fifth lens group 500 moves on the optical axis, there is an active stroke of approaching and moving away from the adjacent lens group. By adjusting the relative positions between the first lens group 100 and the second lens group 200, and between the second lens group 200 and the third lens group 300 within the zoom lens group, the focal length of the lens body can be correspondingly changed to adjust the lens body to the required magnification; by adjusting the relative positions of the fourth lens group 400 and the fifth lens group 500 within the lens barrel, the imaging quality of the lens body can be adjusted to the required imaging quality.

[0069] In this embodiment, let the focal length of the zoom lens be f, 7mm ≤ f ≤ 121mm. The relative movement between the zoom lens group and the compensation lens group enables the focal length of the lens body to be adjusted between 7mm and 121mm, and ensures that the imaging within this focal length range is clear, achieving a large range of zoom from a wide-angle wide field of view to a telephoto narrow field of view.

[0070] Please refer to Figure 3 、 Figure 4 and Figure 5 which are the field curvature diagrams of the wide-angle end, the middle position, and the telephoto end of the zoom lens in this embodiment respectively; Figure 6 、 Figure 7 and Figure 8 which are the distortion diagrams of the wide-angle end, the middle position, and the telephoto end of the zoom lens in this embodiment respectively; Figure 9 、 Figure 10 and Figure 11 which are the spot diagrams of the wide-angle end, the middle position, and the telephoto end of the zoom lens in this embodiment respectively.

[0071] In the embodiment of the present invention, let the F-number of the zoom lens be Fno, 1 ≤ Fno ≤ 3, and let the field of view angle of the zoom lens be ω, 4.3° ≤ ω ≤ 38.8°.

[0072] In the technical solution of the present invention, let the number of lenses in the first lens group 100 be N1, N1 ≤ 5; and / or, let the number of lenses in the second lens group 200 be N2, N2 ≤ 4; and / or, the number of lenses in the third lens group 300 be N3, N3 ≤ 5; and / or, the number of lenses in the fourth lens group 400 be N4, N4 = 1; and / or, the number of lenses in the fifth lens group 500 be N5, N5 ≤ 2.

[0073] In an embodiment of the present invention, the first lens group 100 includes five lenses, which are, in order along the optical axis direction, a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, and a fifth lens 105; the second lens group 200 includes four lenses, which are, in order along the optical axis direction, a sixth lens 201, a seventh lens 202, an eighth lens 203, and a ninth lens 204; the third lens group 300 includes five lenses, which are, in order along the optical axis direction, a tenth lens 301, an eleventh lens 302, a twelfth lens 303, a thirteenth lens 304, and a fourteenth lens 305; the fourth lens group 400 includes a fifteenth lens 401; the fifth lens group 500 includes two lenses, which are, in order along the optical axis direction, a sixteenth lens 501 and a seventeenth lens 502. Among them, the first lens 101 has a positive optical power, the second lens 102 has a negative optical power, the third lens 103 has a positive optical power, the fourth lens 104 has a positive optical power, and the fifth lens 105 has a positive optical power; the sixth lens 201 has a negative optical power, the seventh lens 202 has a negative optical power, the eighth lens 203 has a positive optical power, and the ninth lens 204 has a negative optical power; the tenth lens 301 has a positive optical power, the eleventh lens 302 has a positive optical power, the twelfth lens 303 has a negative optical power, the thirteenth lens 304 has a negative optical power, and the fourteenth lens 305 has a positive optical power; the fifteenth lens 401 has a negative optical power; the sixteenth lens 501 has a positive optical power, and the seventeenth lens 502 has a positive optical power.

[0074] Further, in the order from the object side to the image side of the lens assembly, let the optical powers of the lenses closest to the object side of each lens group be θ1, θ2, θ3, θ4, and θ5 in sequence, that is, the optical power of the first lens 101 is θ1, the optical power of the sixth lens 201 is θ2, the optical power of the tenth lens 301 is θ3, the optical power of the fifteenth lens 401 is θ4, and the optical power of the sixteenth lens 501 is θ5; among them, 0.00026 ≤ θ1 ≤ 0.00027; -0.09 ≤ θ2 ≤ -0.07; 0.036 ≤ θ3 ≤ 0.038; -0.05 ≤ θ4 ≤ -0.03; 0.03 ≤ θ5 ≤ 0.05.

[0075] Further, let the air gap between the first lens group 100 and the second lens group 200 be D1, where 0.515 ≤ D1 ≤ 27.389; let the air gap between the second lens group 200 and the third lens group 300 be D2, where 0.577 ≤ D2 ≤ 36.048; let the air gap between the third lens group 300 and the fourth lens group 400 be D3, where 0.5 ≤ D3 ≤ 2.992; let the air gap between the fourth lens group 400 and the fifth lens group 500 be D4, where 0.276 ≤ D4 ≤ 11.907; let the air gap between the fifth lens group 500 and the image plane 600 be D5, where 3.955 ≤ D5 ≤ 16.362.

[0076] In an embodiment of the present invention, all the lenses of the lens assembly are spherical lenses, which are easy to process, have a low cost, and are easy to promote.

[0077] Specifically, please refer to Tables 1 to 3 below. Tables 1 to 3 provide the specific data for implementing the zoom lens in this embodiment.

[0078] Among them, S1 to S31 in Table 1 represent the surface numbers of each optical element, R represents the curvature radius of the optical element, D represents the thickness of the optical element or the air gap, Nd represents the d-light refractive index of the optical material used, and Vd represents the d-light Abbe number of the optical material used; f ′ in Table 2 represents the system focal length, F-number is the system F number, and ω is the system half field of view angle; D1 in Table 3 represents the variable gap between the first lens group 100 and the second lens group 200, D2 represents the variable gap between the second lens group 200 and the third lens group 300, D3 represents the variable gap between the third lens group 300 and the fourth lens group 400, D4 represents the variable gap between the fourth lens group 400 and the fifth lens group 500, and D5 represents the variable gap between the fifth lens group 500 and the image plane 600.

[0079] Table 1

[0080]

[0081] Table 2

[0082]

[0083] Table 3

[0084]

[0085] In addition, the present invention further provides an imaging device, which includes the zoom lens and the imaging element described in the above technical solution, and the imaging element is configured to receive light of an image formed by the zoom lens. It should be noted that the detailed structure of the zoom lens in the imaging device can refer to the embodiments of the above zoom lens and will not be elaborated here; since the above zoom lens is used in the imaging device of the present invention, therefore, the embodiments of the imaging device of the present invention include all technical solutions of all embodiments of the above zoom lens, and the achieved technical effects are also exactly the same, which will not be elaborated here.

[0086] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structural transformation made under the inventive concept of the present invention by using the content of the specification and drawings of the present invention, or any direct / indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. A zoom lens, characterized in that, It includes a lens assembly and a driving device. The lens assembly includes a plurality of lens groups composed of a plurality of lenses. The driving device is drivingly connected to the plurality of lens groups. The plurality of lens groups are arranged along the optical axis direction of the zoom lens and sequentially include, from the object side to the image side: a first lens group having a positive optical power; a second lens group having a negative optical power; a third lens group having a positive optical power; a fourth lens group having a negative optical power; and, a fifth lens group having a positive optical power; wherein, the first lens group, the second lens group, the third lens group, the fourth lens group and the fifth lens group are movably arranged in the optical axis extension direction, and zooming is achieved by changing the interval between adjacent lens groups and the interval between the fifth lens group and the image plane of the zoom lens through the driving device; wherein, let the maximum diameter of the lens assembly be d, d ≤ 45.6 mm, and let the distance from one end of the first lens group close to the object side to the image plane be L, L ≤ 110 mm; The following conditional expressions are satisfied: 17 ≤ Ft / Fw ≤ 18, wherein, Ft represents the maximum focal length of the zoom lens, and Fw represents the minimum focal length of the zoom lens; Let the focal length of the zoom lens be f, 7 mm ≤ f ≤ 121 mm; Let the F-number of the zoom lens be Fno, 1 ≤ Fno ≤ 3; Let the field angle of the zoom lens be ω, 4.3° ≤ ω ≤ 38.8°; Let the number of lenses in the first lens group be N1, N1 ≤ 5; and / or, Let the number of lenses in the second lens group be N2, N2 ≤ 4; and / or, The number of lenses in the third lens group is N3, N3 ≤ 5; and / or, The number of lenses in the fourth lens group is N4, N4 = 1; and / or, The number of lenses in the fifth lens group is N5, N5 ≤ 2.

2. The zoom lens according to claim 1, characterized in that, In the order from the object side to the image side of the lens assembly, let the optical powers of the lenses closest to the object side in each lens group be θ1, θ2, θ3, θ4 and θ5 respectively; wherein, 0.00026 ≤ θ1 ≤ 0.00027; -0.09 ≤ θ2 ≤ -0.07; 0.036 ≤ θ3 ≤ 0.038; -0.05 ≤ θ4 ≤ -0.03; 0.03 ≤ θ5 ≤ 0.

05.

3. The zoom lens according to claim 1, characterized in that, The first lens group is fixedly arranged, and the second lens group, the third lens group, the fourth lens group and the fifth lens group are all movably arranged along the optical axis extension direction; Let the air spacing between the first lens group and the second lens group be D1, 0.515 ≤ D1 ≤ 27.389; Let the air spacing between the second lens group and the third lens group be D2, 0.577 ≤ D2 ≤ 36.048; Let the air spacing between the third lens group and the fourth lens group be D3, 0.5 ≤ D3 ≤ 2.992; Let the air spacing between the fourth lens group and the fifth lens group be D4, 0.276 ≤ D4 ≤ 11.907; Let the air spacing between the fifth lens group and the image plane be D5, 3.955 ≤ D5 ≤ 16.

362.

4. The zoom lens according to any one of claims 1-3, characterized in that, All lenses of the lens assembly adopt spherical lenses.

5. An imaging device, characterized in that, It includes: The zoom lens according to any one of claims 1 to 4; and an imaging element configured to receive light of an image formed by the zoom lens.

Images