CN211577547U

CN211577547U - Zoom optical system, zoom module and electronic equipment

Info

Publication number: CN211577547U
Application number: CN202020220385.3U
Authority: CN
Inventors: 刘彬彬; 邹海荣; 李明
Original assignee: OFilm Tech Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2020-02-27
Filing date: 2020-02-27
Publication date: 2020-09-25
Anticipated expiration: 2030-02-27

Abstract

The utility model relates to an optical system and zoom module and electronic equipment including above-mentioned optical system zooms. The zoom optical system comprises a first lens with positive refractive power from an object side to an image side in sequence, wherein the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a convex surface; a second lens element with negative refractive power; a third lens element with refractive power; a fourth lens element with refractive power having a concave image-side surface; a fifth lens element with positive refractive power having a convex image-side surface; and a sixth lens element with refractive power. The second lens element, the third lens element and the fourth lens element form a zoom group of the zoom optical system, the zoom group has negative refractive power, and the fifth lens element and the zoom group are respectively movable relative to the first lens element. The zoom optical system has the advantages that the size on the optical axis is short, the requirement of miniaturization design of electronic equipment can be met, and the imaging quality is high.

Description

Zoom optical system, zoom module and electronic equipment

Technical Field

The utility model relates to an optical imaging technology field especially relates to an optical system zooms, module and electronic equipment zooms.

Background

In recent years, electronic devices having a zoom function have been widely pursued because of their wide application range. Under the condition of not changing the shooting distance, the electronic equipment with the zooming function can change the shooting range by changing the focal length of the internal zooming optical system so as to obtain clear images of scenes in different ranges, namely, one zooming optical system can play the role of a plurality of fixed-focus optical systems, and the using range is wide. However, in order to ensure the imaging quality in different ranges, the conventional zoom optical system has a large size, and it is difficult to meet the requirement of miniaturization design of electronic devices.

SUMMERY OF THE UTILITY MODEL

Accordingly, it is desirable to provide a zoom optical system, a zoom module and an electronic device, which are capable of solving the problem that the conventional zoom optical system has a large size and is difficult to meet the requirement of miniaturization design of the electronic device.

A zoom optical system includes, in order from an object side to an image side:

the first lens element with positive refractive power has a convex object-side surface and a convex image-side surface;

a second lens element with negative refractive power;

a third lens element with refractive power;

a fourth lens element with refractive power having a concave image-side surface;

a fifth lens element with positive refractive power having a convex image-side surface;

a sixth lens element with refractive power;

the second lens element, the third lens element and the fourth lens element form a zoom group of the zoom optical system, the zoom group has negative refractive power, and the first lens element and the zoom group are respectively movable relative to the first lens element.

In the zoom optical system, the first lens element has positive refractive power, which is beneficial to shortening the total length of the zoom optical system and the optical axis, and the object-side surface and the image-side surface of the first lens element are both convex surfaces, so that the positive refractive power of the first lens element can be further enhanced, and the total length of the zoom optical system on the optical axis can be further shortened. Therefore, the zoom optical system has a short dimension on the optical axis, and when the zoom optical system is mounted in an electronic device, the requirement of miniaturization design of the electronic device can be met. In addition, the second lens element has negative refractive power, and the zoom lens group also has negative refractive power, so that aberration generated by the first lens element can be corrected. The image side surface of the fourth lens element is a concave surface, which can balance the refractive power configuration of the zoom optical system, so as to avoid the excessive increase of the spherical aberration of the zoom optical system due to the excessive concentration of the refractive power, and correct the astigmatism of the zoom optical system. The fifth lens element with positive refractive power has a convex image-side surface, and the petzval sum of the zoom optical system can be effectively corrected, so that a convergent point of light entering the zoom optical system in a field range is more concentrated on an image surface of the zoom optical system, and the resolution capability of the zoom optical system is improved. Therefore, the size of the zoom optical system on the optical axis is shortened to meet the requirement of miniaturization design of electronic equipment, and meanwhile, the zoom optical system can be ensured to have better imaging quality.

In one embodiment, the zoom optical system satisfies the following relation:

2.1＜TTL/(ImgH*2)＜3；

10°＜HFOV＜15°；

0.7＜DL/TTL＜0.95；

wherein, TTL is a distance on an optical axis from an object-side surface of the first lens element to an image plane of the zoom optical system, ImgH is a half of a diagonal length of the zoom optical system in an effective pixel area, HFOV is a half of a maximum field angle of the zoom optical system, and DL is a distance on an optical axis from an object-side surface of the first lens element to an image-side surface of the sixth lens element. When the relation is satisfied, the zooming optical system has a compact and reasonable structural layout, so that the zooming optical system can meet the requirement of clear image shooting for shot objects at different distances within a certain range through the movement of each lens in the zooming optical system.

In one embodiment, the zoom optical system satisfies the following relation:

1＜TTL/f＜1.5；

wherein f is the total effective focal length of the zoom optical system. When the relation is satisfied, the imaging quality of the zooming optical system is improved through compact and reasonable structural layout and reasonable distribution of the total effective focal length, so that when the scenery in different view field ranges is shot, the image surface of the zooming optical system can form a clearer image.

In one embodiment, the zoom optical system satisfies the following relation:

f5＞0；

wherein f5 is the effective focal length of the fifth lens. When the relation is satisfied, the effective focal length of the fifth lens is reasonably distributed, and when a lens group formed by the second lens, the third lens and the fourth lens moves along the direction of an optical axis in the zooming optical system to realize the zooming function of the zooming optical system, the fifth lens can play a good focal length compensation role in the zooming optical system so as to improve the imaging quality of the zooming optical system.

In one embodiment, the zoom optical system satisfies the following relation:

D2+D3＞D1；

wherein D1 is an axial distance between an image-side surface of the first lens element and an object-side surface of the second lens element, D2 is an axial distance between an image-side surface of the fourth lens element and an object-side surface of the fifth lens element, and D3 is an axial distance between an image-side surface of the fifth lens element and an object-side surface of the sixth lens element. When the relation is satisfied, the zoom optical system has reasonable structural layout on the optical axis, and the direction change of light rays entering the zoom optical system in the zooming process can be slowed down, so that the intensity of stray light generated by the zoom optical system is reduced, and the imaging quality is improved.

In one embodiment, the zoom optical system satisfies the following relation:

0.93＜|f234/f5|＜1.1；

wherein f234 is an effective focal length of a lens group formed by the second lens, the third lens and the fourth lens. When the above relation is satisfied, in the process of zooming of the zoom optical system, the focal lengths of the lens group formed by the second lens, the third lens and the fourth lens and the fifth lens compensate each other, which is beneficial to balancing the aberration of the zoom optical system.

In one embodiment, the zoom optical system satisfies the following relation:

Vn(30)≥3；

wherein Vn (30) is the number of lenses having an Abbe number less than 30 in the zoom optical system. When the above relational expression is satisfied, each lens of the zoom optical system has better quality, and the aberration of the zoom optical system can be better balanced.

In one embodiment, the object-side surface and the image-side surface of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are aspheric. The adoption of the aspheric surface structure can improve the flexibility of the design of each lens, effectively correct the spherical aberration of the zoom optical system and improve the imaging quality.

A zoom module includes a photosensitive element and the zoom optical system according to any of the above embodiments, wherein the photosensitive element is disposed on an image side of the zoom optical system and fixed with respect to the first lens element. The zooming optical system is adopted in the zooming module, the imaging quality is good, the size of the zooming module can be smaller, and the requirement of miniaturization design of electronic equipment can be met when the zooming optical system is applied to the electronic equipment.

An electronic device comprises a shell and the zooming module, wherein the zooming module is arranged on the shell. The electronic equipment is provided with the zooming module, and the electronic equipment can realize miniaturized design due to the small size of the zooming module.

Drawings

FIG. 1 is a schematic view of a zoom optical system in a short focus state according to a first embodiment of the present application;

FIG. 2 is a schematic view of a zoom optical system in a telephoto state according to a first embodiment of the present application;

FIG. 3 is a spherical aberration diagram, an astigmatism diagram and a distortion diagram of a zoom optical system according to a first embodiment of the present application;

FIG. 4 is a diagram illustrating a second embodiment of the present application in a short focus state;

FIG. 5 is a diagram illustrating a zoom optical system in a telephoto state according to a second embodiment of the present application;

FIG. 6 is a spherical aberration diagram, an astigmatism diagram and a distortion diagram of a zoom optical system according to a second embodiment of the present application;

FIG. 7 is a schematic view of a zoom optical system in a short-focus state according to a third embodiment of the present application;

FIG. 8 is a diagram illustrating a zoom optical system in a telephoto state according to a third embodiment of the present application;

FIG. 9 is a spherical aberration diagram, an astigmatism diagram and a distortion diagram of a zoom optical system according to a third embodiment of the present application;

FIG. 10 is a diagram illustrating a zoom optical system in a short focus state according to a fourth embodiment of the present application;

FIG. 11 is a diagram illustrating a zoom optical system in a telephoto state according to a fourth embodiment of the present application;

FIG. 12 is a spherical aberration diagram, an astigmatism diagram and a distortion diagram of a zoom optical system according to a fourth embodiment of the present application;

FIG. 13 is a schematic view of a zoom optical system in a short-focus state according to a fifth embodiment of the present application;

FIG. 14 is a schematic view of a zoom optical system in a telephoto state according to a fifth embodiment of the present application;

FIG. 15 is a spherical aberration diagram, an astigmatism diagram and a distortion diagram of a zoom optical system according to a fifth embodiment of the present application;

FIG. 16 is a diagram illustrating a zoom optical system in a short focus state according to a sixth embodiment of the present application;

FIG. 17 is a diagram illustrating a zoom optical system in a telephoto state according to a sixth embodiment of the present application;

FIG. 18 is a spherical aberration diagram, an astigmatism diagram and a distortion diagram of a zoom optical system according to a sixth embodiment of the present application;

FIG. 19 is a schematic view of a zoom module according to an embodiment of the present application;

fig. 20 is a schematic diagram of an electronic device according to an embodiment of the present application.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. The preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1, in an embodiment of the present application, the zoom optical system 100 includes, in order from an object side to an image side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6. Specifically, the first lens element L1 includes an object-side surface S1 and an image-side surface S2, the second lens element L2 includes an object-side surface S3 and an image-side surface S4, the third lens element L3 includes an object-side surface S5 and an image-side surface S6, the fourth lens element L4 includes an object-side surface S7 and an image-side surface S8, the fifth lens element L5 includes an object-side surface S9 and an image-side surface S10, and the sixth lens element L6 includes an object-side surface S11 and an image-side surface S12. The second lens L2, the third lens L3, and the fourth lens L4 constitute a variable power group L234 of the zoom optical system 100.

The first lens element L1 with positive refractive power is favorable for shortening the total length of the zoom optical system 100, and the object-side surface S1 and the image-side surface S2 of the first lens element L1 are convex, so that the total length of the zoom optical system 100 on the optical axis can be further shortened. Accordingly, the zoom optical system 100 is short in size on the optical axis, and when mounted in an electronic apparatus, the demand for compact design of the electronic apparatus can be satisfied. The second lens element L2 with negative refractive power and the variable power group L234 with negative refractive power can correct the aberration generated by the first lens element L1. The third lens element L3 and the fourth lens element L4 both have refractive power. The image-side surface S8 of the fourth lens element L4 is concave, so that the refractive power configuration of the zoom optical system 100 can be balanced to avoid an excessive increase in spherical aberration of the zoom optical system 100 due to an excessive concentration of refractive power, and to correct astigmatism of the zoom optical system 100. The fifth lens element L5 with positive refractive power has a convex image-side surface S10 of the fifth lens element L5, which can effectively correct the petzval sum of the zoom optical system 100, so that the light rays entering the zoom optical system 100 within the field of view are converged on the image surface S15 of the zoom optical system 100, thereby improving the resolving power of the zoom optical system 100. Therefore, the size of the zoom optical system 100 on the optical axis is shortened to meet the requirement of miniaturization design of electronic equipment, and meanwhile, the zoom optical system 100 can also ensure better imaging quality.

It should be noted that, in some embodiments of the present application, the first lens L1 constitutes a front fixed group of the zoom optical system 100, the sixth lens L6 is fixedly disposed relative to the first lens L1, the sixth lens L6 constitutes a rear fixed group of the zoom optical system 100, the second lens L2, the third lens L3 and the fourth lens L4 together constitute a zoom group L234 of the zoom optical system 100, the zoom group L234 is movable in the optical axis direction of the system between the front fixed group first lens L1 and the rear fixed group sixth lens L6 to change the total effective focal length of the zoom optical system 100, wherein the second lens L2, the third lens L3 and the fourth lens L4 move synchronously to realize the zoom function of the zoom optical system 100. In addition, the fifth lens L5 constitutes a compensation group of the zoom optical system 100, and the fifth lens L5 is also movable in the optical axis direction of the system. The fifth lens L5 in some embodiments may be moved synchronously with the variable power group L234 or asynchronously. When the variable power group L234 moves between the first lens L1 and the sixth lens L6 in the direction of the optical axis, the compensation group fifth lens L5 can also move between the first lens L1 and the sixth lens L6 in the direction of the optical axis, so as to compensate for the aberration of the zoom optical system 100 caused by the movement of the variable power group L234 and the deviation of the optimal imaging position, so that the optimal imaging position of the system can be always on the photosensitive surface of the photosensitive element, thereby ensuring that the zoom optical system 100 can still have excellent imaging quality under shooting conditions of different object distances by adjusting the total effective focal length. For example, in some embodiments, the variable power group L234 is moved along the optical axis in a direction away from the first lens L1, and the fifth lens L5 is moved along the optical axis in a direction close to the sixth lens L6, so that the total effective focal length of the zoom optical system 100 is increased, and the zoom function of the zoom optical system 100 is realized.

In some embodiments, the zoom optical system 100 may be applied to a zoom lens, and in this case, the zoom lens further includes a zoom ring and a fixed focus ring. The first lens L1 and the sixth lens L6 are fixed in the zoom lens, a zoom ring and a fixed focus ring are arranged between the first lens L1 and the sixth lens L6, the zoom ring is fixedly connected with the variable power group L234, and the fixed focus ring is fixedly connected with the fifth lens L5. The zoom ring can drive the variable power group L234 to move between the first lens L1 and the sixth lens L6 along the optical axis of the system, and the fixed focus ring can drive the fifth lens L5 to move between the variable power group L234 and the sixth lens L6 along the optical axis of the system, so as to achieve the zoom function of the zoom lens.

In addition, in some embodiments, the zoom optical system 100 is provided with a stop STO, and the stop STO may be disposed between the third lens L3 and the fourth lens L4. Also, in some embodiments, the zoom optical system 100 further includes an infrared filter L7 disposed on the image side of the sixth lens L6, and the infrared filter L7 includes an object-side surface S13 and an image-side surface S14. Further, the zoom optical system 100 further includes an image plane S15 located on the image side of the sixth lens L6, and incident light can be imaged on the image plane S15 by adjustment of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6. It should be noted that the ir filter L7 may be an ir cut filter for filtering out interfering light and preventing the interfering light from reaching the image plane S15 of the zoom optical system 100 and affecting normal imaging.

In some embodiments, the object-side surface and the image-side surface of each lens of the zoom optical system 100 are aspheric, and the aspheric structure can improve the flexibility of each lens design, effectively correct the spherical aberration of the zoom optical system 100, and improve the imaging quality.

In some embodiments, each lens in the zoom optical system 100 may be made of glass or plastic. The use of a plastic lens such as polycarbonate reduces the weight and production cost of the zoom optical system 100, while the use of a glass lens provides the zoom optical system 100 with excellent optical performance and high temperature resistance. The material of each lens of the zoom optical system 100 may be any combination of glass and plastic, and is not necessarily glass or plastic. Further, in some embodiments, at least two of the lenses of the zoom optical system 100 are made of plastic, and the optical characteristics of the plastic materials used for the at least two lenses are different, so that the aberration of the zoom optical system 100 can be better balanced by balancing the matching of the materials of the lenses, thereby improving the imaging quality.

It is to be noted that the first lens L1 does not mean that there is only one lens, and in some embodiments, there may be two or more lenses in the first lens L1, and the two or more lenses can form a cemented lens, and a surface of the cemented lens closest to the object side can be regarded as the object side surface S1, and a surface of the cemented lens closest to the image side can be regarded as the image side surface S2. Alternatively, although no cemented lens is formed between the lenses of the first lens L1, the distance between the lenses is relatively fixed, and in this case, the object-side surface of the lens closest to the object side is the object-side surface S1, and the image-side surface of the lens closest to the image side is the image-side surface S2. In addition, the number of lenses in the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, or the sixth lens L6 in some embodiments may also be greater than or equal to two, and a cemented lens may be formed between any two adjacent lenses, or may also be a non-cemented lens.

Further, in some embodiments, the zoom optical system 100 satisfies the relationship: 2.1 < TTL/(ImgH 2) < 3; 10 DEG < HFOV < 15 DEG; and DL/TTL is more than 0.7 and less than 0.95; wherein, TTL is an axial distance from the object-side surface S1 of the first lens element L1 to the image plane S15 of the zoom optical system 100, ImgH is a half of a diagonal length of the zoom optical system 100 in the effective pixel area, HFOV is a half of a maximum field angle of the zoom optical system 100, that is, HFOV is a half of a diagonal field angle of the zoom optical system 100, and DL is an axial distance from the object-side surface S1 of the first lens element L1 to the image-side surface S12 of the sixth lens element L6. Specifically, TTL/(ImgH × 2) may be 2.7. HFOVs may be 11.06 °, 11.28 °, 11.40 °, 11.67 °, 11.92 °, 12.11 °, 12.35 °, 12.90 °, 13.42 °, or 13.70 °. The DL/TTL can be 0.917, 0.921, 0.924, 0.928, 0.932, 0.933, 0.935, 0.937, 0.938, or 0.940. When the above relation is satisfied, the zoom optical system 100 has a compact and reasonable structural layout, and thus, the zoom optical system 100 can meet the requirement of clear image shooting for the shot objects at different distances within a certain range through the movement of each lens inside the zoom optical system 100.

In some embodiments, the zoom optical system 100 satisfies the following relationship: TTL/f is more than 1 and less than 1.5; where f is the total effective focal length of the zoom optical system 100. Specifically, TTL/f can be 1.140, 1.151, 1.163, 1.211, 1.298, 1.301, 1.335, 1.386, 1.402, or 1.416. When the above relational expression is satisfied, the imaging quality of the zoom optical system 100 is improved through the compact and reasonable structural layout and the reasonable distribution of the total effective angle, so that when scenes in different field ranges are shot, the image plane S15 of the zoom optical system 100 can form a clearer image.

In some embodiments, the zoom optical system 100 satisfies the following relationship: f5 > 0; where f5 is the effective focal length of the fifth lens L5. Specifically, f5 may be 10.065, 10.098, 10.155, 10.236, 10.322, 10.458, 10.523, 10.687, 10.711, or 10.786, with the unit of f5 being mm. When the above relation is satisfied, by appropriately allocating the effective focal length of the fifth lens L5, when the variable power group L234 moves in the direction of the optical axis between the first lens L1 and the sixth lens L6 to realize the zoom function of the zoom optical system 100, the fifth lens L5 can perform a good focal length compensation function in the zoom optical system 100 to improve the imaging quality of the zoom optical system 100.

In some embodiments, the zoom optical system 100 satisfies the following relationship: d2+ D3 > D1; the unit of D1 is a distance on the optical axis from the image-side surface S2 of the first lens element L1 to the object-side surface S3 of the second lens element L2, and is mm, the unit of D2 is a distance on the optical axis from the image-side surface S8 of the fourth lens element L4 to the object-side surface S9 of the fifth lens element L5, and the unit of D3 is mm from the image-side surface S10 of the fifth lens element L5 to the object-side surface S11 of the sixth lens element L6. Specifically, D1 may be 0.433, 0.456, 0.498, 0.535, 0.574, 0.629, 0.667, 0.685, 0.722, or 0.726. D2 may be 2.563, 2.855, 3.112, 3.864, 3.945, 4.102, 4.632, 4.801, 4.898, or 4.954. D3 may be 0.102, 0.323, 0.587, 0.965, 1.322, 1.593, 1.865, 1.996, 2.155, or 2.377. When the above relation is satisfied, the zoom optical system 100 has a reasonable structural layout on the optical axis, and the direction change of light rays entering the zoom optical system 100 in the zooming process can be slowed down, so that the intensity of stray light generated by the zoom optical system 100 is reduced, and the imaging quality is improved.

Further, the movement of the variable power group L234 and the fifth lens L5 between the first lens L1 and the sixth lens L6 along the optical axis direction causes the values of D1, D2 and D3 to change, thereby causing the total effective focal length of the zoom optical system 100 to change. In the embodiments of the present application, only the numerical values of D1, D2, and D3 of the zoom optical system 100 in the three states of short focus, middle focus, and long focus are listed, but the zoom optical system 100 is not limited to be converted in the three specific states. In one embodiment, the total effective focal length of the time-varying focusing optical system 100 in the short-focus state is the minimum of the total effective focal lengths in the three states, and the total effective focal length of the time-varying focusing optical system 100 in the long-focus state is the maximum of the total effective focal lengths in the three states. Of course, the above three states are only three of the changing states when the total effective focal length of the zoom optical system 100 changes, and the total effective focal length of the zoom optical system 100 may also be other values, and accordingly, the values of D1, D2, and D3 may also be other values.

In some embodiments, the zoom optical system 100 satisfies the following relationship: 0.93 < | f234/f5| < 1.1; where f234 is an effective focal length of a lens group formed by the second lens L2, the third lens L3, and the fourth lens L4, and the unit of f234 is mm. In particular, f234 can be-10.907, -10.862, -10.655, -10.363, -10.124, -9.989, -9.753, -9.711, -9.685, or-9.504. When the above relation is satisfied, in the zooming optical system 100, the focal lengths between the variable power group L234 and the fifth lens L5 are mutually compensated during zooming, which is beneficial to balance the aberration of the zooming optical system 100.

In some embodiments, the zoom optical system 100 satisfies the following relationship: vn (30) is more than or equal to 3; where Vn (30) is the number of lenses having an abbe number less than 30 in the zoom optical system 100. Specifically, Vn (30) may be 4. When the above relation is satisfied, each lens of the zoom optical system 100 has better quality, and the aberration of the zoom optical system 100 can be better balanced, thereby improving the imaging quality.

Based on the above description of the embodiments, more specific embodiments and drawings are set forth below for detailed description.

First embodiment

Referring to fig. 1, fig. 2 and fig. 3, fig. 1 is a schematic diagram of a zoom optical system 100 in a short-focus state in a first embodiment, and fig. 2 is a schematic diagram of the zoom optical system 100 in a long-focus state in the first embodiment. The zoom optical system 100 includes, in order from the object side to the image side, a first lens element L1 with positive refractive power, a second lens element L2 with negative refractive power, a third lens element L3 with negative refractive power, a stop STO, a fourth lens element L4 with positive refractive power, a fifth lens element L5 with positive refractive power, and a sixth lens element L6 with negative refractive power. Fig. 3 is a graph of the spherical aberration, astigmatism and distortion of the zoom optical system 100 in the first embodiment, which is sequentially from left to right, wherein the astigmatism and the distortion are both graphs at 555nm, and the other embodiments are the same.

The object-side surface S1 of the first lens element L1 is convex at the optical axis and convex at the circumference;

the image-side surface S2 of the first lens element L1 is convex at the optical axis and convex at the circumference;

the object-side surface S3 of the second lens element L2 is concave at the optical axis and convex at the circumference;

the image-side surface S4 of the second lens element L2 is concave at the optical axis and concave at the circumference;

the object-side surface S5 of the third lens element L3 is convex at the optical axis and convex at the circumference;

the image-side surface S6 of the third lens element L3 is concave at the optical axis and concave at the circumference;

the object-side surface S7 of the fourth lens element L4 is convex at the optical axis and convex at the circumference;

the image-side surface S8 of the fourth lens element L4 is concave at the optical axis and concave at the circumference;

the object-side surface S9 of the fifth lens element L5 is concave at the optical axis and concave at the circumference;

the image-side surface S10 of the fifth lens element L5 is convex at the optical axis and convex at the circumference;

the object-side surface S11 of the sixth lens element L6 is concave at the optical axis and concave at the circumference;

the image-side surface S12 of the sixth lens element L6 is concave along the optical axis and convex along the circumference.

It should be noted that, in the present application, when a surface of a lens is described as being convex at the optical axis (the central region of the side), it is understood that the region of the surface of the lens near the optical axis is convex, and thus the surface can also be considered as being convex at the optical paraxial region. When a surface of a lens is described as concave at the circumference, it is understood that the surface is concave near the region of maximum effective radius. For example, when the surface is convex at the optical axis and also convex at the circumference, the shape of the surface from the center (optical axis) to the edge direction may be purely convex; or a convex shape at the center is firstly transited to a concave shape, and then becomes a convex shape near the maximum effective radius. Here, examples are made only to illustrate the relationship at the optical axis and at the circumference, and various shape structures (concave-convex relationship) of the surface are not fully embodied, but other cases can be derived from the above examples.

The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 are all made of plastic.

Further, the zoom optical system 100 satisfies the relation: TTL/(ImgH × 2) ═ 2.7; and DL/TTL is 0.916666667. And when the zoom optical system 100 is in a short focus state, HFOV is 13.7; in a medium coke state, HFOV is 13.1; in a long-focus state, HFOV is 12.55. Wherein, TTL is the distance on the optical axis from the object-side surface S1 of the first lens L1 to the image plane S15 of the zoom optical system 100, ImgH is half the diagonal length of the zoom optical system 100 in the effective pixel area, HFOV is half the maximum field angle of the zoom optical system 100, and DL is the distance on the optical axis from the object-side surface S1 of the first lens L1 to the image plane S12 of the sixth lens L6. When the above relation is satisfied, the zoom optical system 100 has a compact and reasonable structural layout, and thus, the zoom optical system 100 can meet the requirement of clear image shooting for the shot objects at different distances within a certain range through the movement of each lens inside the zoom optical system 100.

The zoom optical system 100 satisfies the relation: when the zoom optical system 100 is in a short focus state, TTL/f is 1.304833; in a mid-focus state, TTL/f is 1.195911; in one tele state, TTL/f is 1.13961. Where f is the total effective focal length of the zoom optical system 100. When the above relation is satisfied, the imaging quality of the zoom optical system 100 is improved through the compact and reasonable structural layout and the reasonable distribution of the total effective angle, so that when scenes in different field ranges are shot, the image plane S15 of the zoom optical system 100 can also form a clearer image.

The zoom optical system 100 satisfies the relation: f5 is 10.78613. Where f5 is the effective focal length of the fifth lens L5. When the above relation is satisfied, by appropriately allocating the effective focal length of the fifth lens L5, when the variable power group L234 moves in the direction of the optical axis between the first lens L1 and the sixth lens L6 to realize the zoom function of the zoom optical system 100, the fifth lens L5 can perform a good focal length compensation function in the zoom optical system 100 to improve the imaging quality of the zoom optical system 100.

The zoom optical system 100 satisfies the relation: when the zoom optical system 100 is in a short-focus state, D1 ═ 0.5518224, D2 ═ 3.611136, D3 ═ 2.140662; in a medium coke state, D1 ═ 0.607735, D2 ═ 4.40985, D3 ═ 1.289771; in a state of long focus, D1-0.644651, D2-4.854519, and D3-0.794074. The unit of D1 is a distance on the optical axis from the image-side surface S2 of the first lens element L1 to the object-side surface S3 of the second lens element L2, and is mm, the unit of D2 is a distance on the optical axis from the image-side surface S8 of the fourth lens element L4 to the object-side surface S9 of the fifth lens element L5, and the unit of D3 is mm from the image-side surface S10 of the fifth lens element L5 to the object-side surface S11 of the sixth lens element L6. When the above conditional expression is satisfied, the conditional expression is satisfied: when D2+ D3 > D1, the zoom optical system 100 has a reasonable structural layout on the optical axis, which can slow down the direction change of the light entering the zoom optical system 100 during the zooming process, thereby reducing the intensity of stray light generated by the zoom optical system 100 and improving the imaging quality.

Further, when the zoom optical system 100 is in a short-focus state, the total effective focal length f of the zoom optical system 100 is 10.76 mm; in a medium coke state, f is 11.74 mm; in a char state, f is 12.32 mm. Also, referring to fig. 1 and 2, in a zoom adjustment mode, when the zoom optical system 100 changes from the short-focus state to the long-focus state, the first lens L1 and the sixth lens L6 are fixed in position, the variable power group L234 moves along the optical axis in a direction away from the first lens L1, the fifth lens L5 moves along the optical axis in a direction closer to the sixth lens L6, and the distance between the variable power group L234 and the fifth lens L5 on the optical axis becomes larger, and the moving tendency in other embodiments is the same.

The zoom optical system 100 satisfies the relation: f234 ═ 11.5791 mm. Wherein f234 is the effective focal length of the lens group consisting of the second lens L2, the third lens L3 and the fourth lens L4. When the above relation is satisfied, the relation is satisfied: when 0.93 < | f234/f5| < 1.1, the focal lengths between the variable power group L234 and the fifth lens L5 compensate each other during zooming of the zoom optical system 100, which is beneficial to balancing the aberration of the zoom optical system 100.

The zoom optical system 100 satisfies the relation: vn (30) ═ 4; where Vn (30) is the number of lenses having an abbe number less than 30 in the zoom optical system 100. When the above relation is satisfied, each lens of the zoom optical system 100 has better quality, and the aberration of the zoom optical system 100 can be better balanced, thereby improving the imaging quality.

In addition, the parameters of the zoom optical system 100 are given by table 1. Among them, the image plane S15 in table 1 may be understood as an imaging plane of the zoom optical system 100. The elements from the object plane (not shown) to the image plane S15 are sequentially arranged in the order of the elements from top to bottom in table 1. The Y radius in table 1 is the radius of curvature of the object-side surface or the image-side surface of the corresponding surface number at the optical axis. Surface number 1 and surface number 2 are the object-side surface S1 and the image-side surface S2 of the first lens L1, respectively, that is, in the same lens, the surface with the smaller surface number is the object-side surface, and the surface with the larger surface number is the image-side surface. The first numerical value in the "thickness" parameter column of the first lens element L1 is the axial thickness of the lens element, and the second numerical value is the axial distance from the image-side surface of the lens element to the object-side surface of the following lens element in the image-side direction.

Note that, in this embodiment and the following embodiments, the zoom optical system 100 may not be provided with the infrared filter L7, but the distance from the image-side surface S12 to the image surface S15 of the sixth lens L6 at this time remains unchanged.

In the first embodiment, the distance TTL between the object-side surface S1 of the first lens L1 and the image plane S15 on the optical axis is 14.04mm, the distance DL between the object-side surface S1 of the first lens L1 and the image-side surface S12 of the sixth lens L6 on the optical axis is 12.87mm, the half ImgH of the diagonal length of the zoom optical system 100 in the effective pixel area is 2.6mm, and the maximum imaging circle diameter MIC of the zoom optical system 100 in the image plane S15 is 5.5 m.

And the focal length and refractive index of each lens are values at d-line (587.56nm), and the same applies to other embodiments.

TABLE 1

Further, aspherical coefficients of the image-side surface or the object-side surface of each lens of the zoom optical system 100 are given by table 2. In which the surface numbers 1-12 represent image side surfaces or object side surfaces S1-S12, respectively. And K-a20 from top to bottom respectively represent aspheric coefficients, where K represents a conic constant, a4 represents a quartic aspheric coefficient, a6 represents a sextic aspheric coefficient, A8 represents an octal aspheric coefficient, and so on. In addition, the aspherical surface coefficient formula is as follows:

where Z is the distance from the corresponding point on the aspherical surface to a plane tangent to the surface vertex, r is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the aspherical surface vertex, k is a conic constant, and Ai is a coefficient corresponding to the i-th high order term in the aspherical surface type formula, such as a4, a6, or A8.

TABLE 2

Second embodiment

Referring to fig. 4, fig. 5, and fig. 6, fig. 4 is a schematic diagram of a zoom optical system 100 in a second embodiment in a short-focus state, and fig. 5 is a schematic diagram of the zoom optical system 100 in the second embodiment in a long-focus state. The zoom optical system 100 includes, in order from the object side to the image side, a first lens element L1 with positive refractive power, a second lens element L2 with negative refractive power, a third lens element L3 with positive refractive power, a stop STO, a fourth lens element L4 with positive refractive power, a fifth lens element L5 with positive refractive power, and a sixth lens element L6 with positive refractive power. Fig. 6 is a graph of spherical aberration, astigmatism and distortion of the zoom optical system 100 in the second embodiment, which is shown from left to right.

In addition, the parameters of the zoom optical system 100 are given in table 3, and the definitions of the parameters can be derived from the first embodiment, which is not described herein.

TABLE 3

And, when the zoom optical system 100 is in a short focus state, f is 10.75 mm; in a medium coke state, f is 11.75 mm; in a char state, f is 12.31 mm.

Further, the aspheric coefficients of the image-side surface or the object-side surface of each lens of the zoom optical system 100 are shown in table 4, and the definitions of the parameters can be derived from the first embodiment, which is not described herein again.

TABLE 4

Furthermore, according to the above provided parameter information, the following relationship can be derived:

TTL/(ImgH*2)＝2.7；DL/TTL＝0.940883191；f5＝10.57311mm；f234＝-10.6176mm；

Vn(30)＝4。

and when the zoom optical system 100 is in a short focus state, HFOV is 13.16 °; TTL/f is 1.306047; d1 is 0.544513 mm; d2 is 3.564296 mm; d3 is 1.853047 mm. HFOV is 12.2 ° when in a medium coke state; TTL/f is 1.194894; d1 is 0.664997 mm; d2 is 4.469058 mm; d3 is 0.837801 mm. HFOV at 11.75 ° in a state of long focus; TTL/f is 1.140536; d1 is 0.690522 mm; d2 is 4.954337 mm; d3 is 0.326996 mm.

Third embodiment

Referring to fig. 7, 8 and 9, fig. 7 is a schematic diagram of a zoom optical system 100 in a short-focus state in a third embodiment, and fig. 8 is a schematic diagram of the zoom optical system 100 in a long-focus state in the third embodiment. The zoom optical system 100 includes, in order from the object side to the image side, a first lens element L1 with positive refractive power, a second lens element L2 with negative refractive power, a third lens element L3 with positive refractive power, a stop STO, a fourth lens element L4 with positive refractive power, a fifth lens element L5 with positive refractive power, and a sixth lens element L6 with negative refractive power. Fig. 9 is a graph showing the spherical aberration, astigmatism and distortion of the zoom optical system 100 in the third embodiment in the order from left to right.

the object-side surface S3 of the second lens element L2 is concave at the optical axis and concave at the circumference;

the image-side surface S12 of the sixth lens element L6 is convex along the optical axis and convex along the circumference.

In addition, the parameters of the zoom optical system 100 are given in table 5, and the definitions of the parameters can be derived from the first embodiment, which is not described herein.

TABLE 5

And, when the zoom optical system 100 is in a short focus state, f is 10.8 mm; in a medium coke state, f is 11.7 mm; in a char state, f is 12.2 mm.

Further, the aspheric coefficients of the image-side surface or the object-side surface of each lens of the zoom optical system 100 are shown in table 6, and the definitions of the parameters can be derived from the first embodiment, which is not described herein again.

TABLE 6

TTL/(ImgH*2)＝2.7；DL/TTL＝0.939458689；f5＝10.54453mm；f234＝-10.8067mm；

Vn(30)＝4。

and when the zoom optical system 100 is in a short focus state, HFOV is 13.2 °; TTL/f is 1.3; d1 is 0.529575 mm; d2 is 3.518013 mm; d3 is 1.562384 mm. HFOV is 12.24 ° when in a medium focus state; TTL/f is 1.2; d1 is 0.654841 mm; d2 is 4.310994 mm; d3 is 0.654137 mm. In a long focus state, HFOV is 11.79 °; TTL/f is 1.15082; d1 is 0.68837 mm; d2 is 4.731202 mm; d3 ═ 0.2004 mm.

Fourth embodiment

Referring to fig. 10, fig. 11 and fig. 12, fig. 10 is a schematic diagram of a zoom optical system 100 in a short-focus state in a fourth embodiment, and fig. 11 is a schematic diagram of the zoom optical system 100 in a long-focus state in the fourth embodiment. The zoom optical system 100 includes, in order from the object side to the image side, a first lens element L1 with positive refractive power, a second lens element L2 with negative refractive power, a third lens element L3 with positive refractive power, a stop STO, a fourth lens element L4 with positive refractive power, a fifth lens element L5 with positive refractive power, and a sixth lens element L6 with negative refractive power. Fig. 12 is a graph showing the spherical aberration, astigmatism and distortion of the zoom optical system 100 in the fourth embodiment in the order from left to right.

the object-side surface S11 of the sixth lens element L6 is convex at the optical axis and concave at the circumference;

Further, the object-side surface S11 of the sixth lens element L6 is convex along the optical axis, the image-side surface S12 is concave along the optical axis, and the image-side surface S12 is convex along the circumference, i.e., the image-side surface S12 has at least one convex point along the off-axis. By such arrangement, astigmatism of the zoom optical system 100 can be effectively corrected, off-axis aberration can be corrected, imaging quality can be further improved, and meanwhile, the principal point of the zoom optical system 100 is far away from the image plane S15, so that the focal length of the zoom optical system 100 is shortened, the size of the zoom optical system 100 on the optical axis is further shortened, and the zoom optical system 100 can further meet the requirement of miniaturization design of electronic equipment.

In addition, the parameters of the zoom optical system 100 are given in table 7, and the definitions of the parameters can be derived from the first embodiment, which is not described herein.

TABLE 7

And, when the zoom optical system 100 is in a short focus state, f is 10.8 mm; in a medium coke state, f is 11.76 mm; in a char state, f is 12.2 mm.

Further, the aspheric coefficients of the image-side surface or the object-side surface of each lens of the zoom optical system 100 are given in table 8, and the definitions of the parameters can be derived from the first embodiment, which is not described herein again.

TABLE 8

TTL/(ImgH*2)＝2.7；DL/TTL＝0.934472934；f5＝10.50032mm；f234＝-10.9074mm；

Vn(30)＝4。

and when the zoom optical system 100 is in a short focus state, HFOV is 13.42 °; TTL/f is 1.3; d1 is 0.504692 mm; d2 is 3.435929 mm; d3 is 1.561913 mm. HFOV is 12.4 ° when in a medium coke state; TTL/f is 1.193878; d1 is 0.64634 mm; d2 is 4.272064 mm; d3 is 0.59065 mm. HFOV is 11.97 ° when in a long-focus state; TTL/f is 1.15082; d1 is 0.678644 mm; d2 is 4.645257 mm; d3 is 0.188634 mm.

Fifth embodiment

Referring to fig. 13, 14 and 15, fig. 13 is a schematic diagram of a zoom optical system 100 in a short-focus state in a fifth embodiment, and fig. 14 is a schematic diagram of the zoom optical system 100 in a long-focus state in the fifth embodiment. The zoom optical system 100 includes, in order from the object side to the image side, a first lens element L1 with positive refractive power, a second lens element L2 with negative refractive power, a third lens element L3 with negative refractive power, a stop STO, a fourth lens element L4 with positive refractive power, a fifth lens element L5 with positive refractive power, and a sixth lens element L6 with negative refractive power. Fig. 15 is a graph showing the spherical aberration, astigmatism and distortion of the zoom optical system 100 in the fifth embodiment in the order from left to right.

In addition, the parameters of the zoom optical system 100 are given in table 9, and the definitions of the parameters can be derived from the first embodiment, which is not described herein.

TABLE 9

And, when the zoom optical system 100 is in a short focus state, f is 9.93 mm; in a medium coke state, f is 11.62 mm; in a char state, f is 12.13 mm.

Further, the aspheric coefficients of the image-side surface or the object-side surface of each lens of the zoom optical system 100 are given in table 10, and the definitions of the parameters can be derived from the first embodiment, which is not described herein again.

Watch 10

TTL/(ImgH*2)＝2.7；DL/TTL＝0.929487179；f5＝10.11845mm；f234＝-10.5499mm；

Vn(30)＝4。

and when the zoom optical system 100 is in a short focus state, HFOV is 13.11 °; TTL/f is 1.413897; d1 is 0.455355 mm; d2 is 2.691823 mm; d3 is 2.301812 mm. HFOV is 11.47 ° when in a medium coke state; TTL/f is 1.208262; d1 is 0.704234 mm; d2 is 4.211118 mm; d3 is 0.538792 mm. HFOV is 11.06 ° when in a long-focus state; TTL/f is 1.157461; d1 is 0.721666 mm; d2 is 4.628373 mm; d3 is 0.104509 mm.

Sixth embodiment

Referring to fig. 16, 17 and 18, fig. 16 is a schematic diagram of a zoom optical system 100 in a sixth embodiment in a short-focus state, and fig. 17 is a schematic diagram of the zoom optical system 100 in the sixth embodiment in a long-focus state. The zoom optical system 100 includes, in order from the object side to the image side, a first lens element L1 with positive refractive power, a second lens element L2 with negative refractive power, a third lens element L3 with positive refractive power, a stop STO, a fourth lens element L4 with negative refractive power, a fifth lens element L5 with positive refractive power, and a sixth lens element L6 with negative refractive power. Fig. 18 is a graph showing the spherical aberration, astigmatism and distortion of the zoom optical system 100 in the sixth embodiment in the order from left to right.

the image-side surface S4 of the second lens element L2 is convex at the optical axis and convex at the circumference;

the object-side surface S11 of the sixth lens element L6 is convex at the optical axis and convex at the circumference;

the image-side surface S12 of the sixth lens element L6 is concave along the optical axis and concave along the circumference.

In addition, the parameters of the zoom optical system 100 are given in table 11, and the definitions of the parameters can be derived from the first embodiment, which is not described herein.

TABLE 11

And, when the zoom optical system 100 is in a short focus state, f is 9.91 mm; in a medium coke state, f is 11.62 mm; in a char state, f is 12.13 mm.

Further, the aspheric coefficients of the image-side surface or the object-side surface of each lens of the zoom optical system 100 are given in table 12, and the definitions of the parameters can be derived from the first embodiment, which is not described herein again.

TABLE 12

TTL/(ImgH*2)＝2.7；DL/TTL＝0.925925926；f5＝10.06431mm；f234＝-9.50306mm；

Vn(30)＝4。

and when the zoom optical system 100 is in a short focus state, HFOV is 13.53 °; TTL/f is 1.416751; d1 is 0.432284 mm; d2 is 2.562738 mm; d3 is 2.377303 mm. HFOV is 11.83 ° when in a medium coke state; TTL/f is 1.208262; d1 is 0.707238 mm; d2 is 4.119785 mm; d3 is 0.547578 mm. HFOV is 11.4 ° when in a long-focus state; TTL/f is 1.157461; d1 is 0.726793 mm; d2 is 4.547918 mm; d3 is 0.101815 mm.

Referring to fig. 19, in some embodiments, the zoom optical system 100 may be assembled with the photosensitive element 210 to form a zoom module 200. The sixth lens element L6 and the photosensitive element 210 are fixed with respect to the first lens element L1, and the variable power group L234 and the fifth lens element L5 can move with respect to the first lens element L1, respectively, so as to achieve the zooming function of the zoom module 200. At this time, the image plane S15 of the zoom optical system 100 can be regarded as the light-sensing plane of the light-sensing element 210. The zoom module 200 may further include an infrared filter L7, wherein the infrared filter L7 is disposed between the image side surface S12 and the image surface S15 of the sixth lens element L6. Specifically, the photosensitive element 210 may be a Charge Coupled Device (CCD) or a complementary metal-Oxide Semiconductor (CMOS) element. The zoom optical system 100 is adopted in the zoom module 200, so that the imaging quality is good, the size of the zoom module 200 can be smaller, and the requirement of miniaturization design of electronic equipment can be met when the zoom optical system is applied to the electronic equipment.

Referring to fig. 20, in some embodiments, the zoom module 200 may be applied to an electronic device 300, where the electronic device 300 includes a housing 310, and the zoom module 200 is mounted on the housing 310. Specifically, the electronic device 300 may be a smartphone, a camera, a video camera, or a tablet computer having a zoom function. Because the imaging quality of the zoom module 200 is good and the size is small, the zoom module 200 is adopted in the electronic device 300, the imaging quality of the electronic device 300 can be improved, and meanwhile, the electronic device 300 can be designed in a miniaturized manner.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A zoom optical system, comprising, in order from an object side to an image side:

a second lens element with negative refractive power;

a third lens element with refractive power;

a sixth lens element with refractive power;

the second lens element, the third lens element and the fourth lens element form a zoom group of the zoom optical system, the zoom group has negative refractive power, and the fifth lens element and the zoom group are respectively movable relative to the first lens element.

2. Zoom optical system according to claim 1, characterized in that the following relation is satisfied:

2.1＜TTL/(ImgH*2)＜3；

10°＜HFOV＜15°；

0.7＜DL/TTL＜0.95；

wherein, TTL is a distance on an optical axis from an object-side surface of the first lens element to an image plane of the zoom optical system, ImgH is a half of a diagonal length of the zoom optical system in an effective pixel area, HFOV is a half of a maximum field angle of the zoom optical system, and DL is a distance on an optical axis from an object-side surface of the first lens element to an image-side surface of the sixth lens element.

3. Zoom optical system according to claim 1, characterized in that the following relation is satisfied:

1＜TTL/f＜1.5；

wherein f is the total effective focal length of the zoom optical system.

4. Zoom optical system according to claim 1, characterized in that the following relation is satisfied:

f5＞0；

wherein f5 is the effective focal length of the fifth lens.

5. Zoom optical system according to claim 1, characterized in that the following relation is satisfied:

D2+D3＞D1；

wherein D1 is an axial distance between an image-side surface of the first lens element and an object-side surface of the second lens element, D2 is an axial distance between an image-side surface of the fourth lens element and an object-side surface of the fifth lens element, and D3 is an axial distance between an image-side surface of the fifth lens element and an object-side surface of the sixth lens element.

6. Zoom optical system according to claim 1, characterized in that the following relation is satisfied:

0.93＜|f234/f5|＜1.1；

wherein f234 is an effective focal length of a lens group formed by the second lens, the third lens and the fourth lens.

7. Zoom optical system according to claim 1, characterized in that the following relation is satisfied:

Vn(30)≥3；

wherein Vn (30) is the number of lenses having an Abbe number less than 30 in the zoom optical system.

8. Zoom optical system of any of claims 1-7, wherein the object-side and image-side surfaces of the first, second, third, fourth, fifth, and sixth lenses are aspheric.

9. A zoom module comprising a photosensitive element and the zoom optical system according to any one of claims 1 to 8, wherein the photosensitive element is disposed on an image side of the zoom optical system and fixed with respect to the first lens element.

10. An electronic device comprising a housing and the zoom module of claim 9, the zoom module being mounted on the housing.