CN112505895A

CN112505895A - Optical lens, camera module and electronic device

Info

Publication number: CN112505895A
Application number: CN202011501991.3A
Authority: CN
Inventors: 乐宇明; 蔡雄宇; 董勇兵; 赵迪
Original assignee: Tianjin OFilm Opto Electronics Co Ltd
Current assignee: Tianjin OFilm Opto Electronics Co Ltd
Priority date: 2020-12-17
Filing date: 2020-12-17
Publication date: 2021-03-16

Abstract

The invention discloses an optical lens, a camera module and an electronic device. The optical lens assembly includes, in order from an object side to an image side, a first lens element with negative refractive power, a second lens element with negative refractive power having a concave or convex object-side surface, a third lens element with positive refractive power having a convex object-side surface and a flat or concave image-side surface, a fourth lens element with positive refractive power, a fifth lens element with positive refractive power, a sixth lens element with negative refractive power having a concave object-side surface and a concave image-side surface, a seventh lens element with positive refractive power having a convex object-side surface and a convex image-side surface. The optical lens comprises a diaphragm; the optical lens satisfies the following relation: 6.7(mm 10)^‑6/℃)<(CT5‑CT6)*(α5‑α6)<11.7(mm*10^‑6/° c). Thus, the optical lens is under high temperature or low temperature conditionGood imaging quality is maintained.

Description

Optical lens, camera module and electronic device

Technical Field

The present disclosure relates to optical imaging technologies, and particularly to an optical lens, a camera module and an electronic device.

Background

With the rapid development of science and technology, the technology of photography and image capture is also continuously developed. The optical lens can be applied to the industries of vehicle-mounted, monitoring and the like. When the optical lens is applied to the vehicle-mounted industry, the optical lens can be arranged in front of a vehicle and used as a camera in an advanced driver assistance system to provide lane departure warning, automatic lane keeping assistance and other functions; the automobile parking device can be started when the automobile is parked in a place, the barrier in the front of the automobile can be visually seen through the camera, the driving environment in the front is judged, and accidents are avoided. How to reduce the influence of temperature on the optical lens is still a technical issue of great attention, so that the lens can maintain good imaging quality at different temperatures.

Disclosure of Invention

In view of the above, embodiments of the present invention provide an optical lens, a camera module and an electronic device.

In the optical lens system according to the embodiment of the present invention, an object-side surface of the optical lens system includes, in order from an object side to an image side, a first lens element with negative refractive power, a second lens element with negative refractive power, an object-side surface of the optical lens system can be a concave surface or a convex surface, a third lens element with positive refractive power, an object-side surface of the optical lens system can be a convex surface, an image-side surface of the optical lens system can be a flat surface or a concave surface, a fourth lens element with positive refractive power, a fifth lens element with positive refractive power, a sixth lens element with negative refractive power, an object-side surface and an image-side surface of the optical lens system are both concave, a seventh lens element with positive refractive power, and an. The optical lens also comprises a diaphragm;

the optical lens satisfies the following relation:

6.7(mm*10^-6/℃)<(CT5-CT6)*(α5-α6)<11.7(mm*10^-6/℃)；……(1)

wherein CT5 is the thickness of the fifth lens element on the optical axis, CT6 is the thickness of the sixth lens element on the optical axis, α 5 is the thermal expansion coefficient of the fifth lens element at-30 ℃ to 70 ℃, α 6 is the thermal expansion coefficient of the sixth lens element at-30 ℃ to 70 ℃, and the unit is 10^-6/℃。

In the optical lens of the embodiment of the application, the value obtained by multiplying the difference between the central thickness of the fifth lens on the optical axis and the central thickness of the sixth lens on the optical axis by the difference between the thermal expansion coefficient of the fifth lens at-30-70 ℃ and the thermal expansion coefficient of the sixth lens at-30-70 ℃ is 6.7-11.7, the influence of temperature on the lens is reduced through reasonable collocation of materials, the central thickness difference and the material characteristic difference of the fifth lens and the sixth lens of the camera module of the embodiment of the invention are reduced, and the lens keeps good imaging quality under the conditions of high temperature or low temperature.

In some embodiments, the optical lens satisfies the following relationship:

11.5mm<f1*f2/f<17.7mm；……(2)

wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f is the focal length of the optical lens.

Under the condition that the relation (2) is satisfied, the first lens of the optical lens provides negative refractive power for the optical lens, the negative lens is arranged close to the object side, the negative refractive power is provided for the optical lens, light rays emitted into the optical lens at a large angle can be captured, and the field angle range of the optical lens is enlarged; the second lens is set as a negative lens to provide negative refractive power for the optical lens, so that the light width is favorably expanded, the light rays which are shot after the light rays with large angles are refracted by the first lens are further expanded and are full of pupils, and the light rays are fully transmitted to a high-pixel imaging surface, so that a wider field range is obtained, and the characteristic of high pixel of the optical lens is favorably realized; if the upper limit of the relation (2) is exceeded, the combined focal length of the first lens element and the second lens element is larger, the overall refractive power is smaller, and light rays cannot be well collected; if the lower limit of the relation (2) is exceeded, the combined focal length of the first lens element and the second lens element is small, the overall refractive power is large, high-order aberration is easy to generate, and the suppression of chromatic aberration is not facilitated.

In some embodiments, the optical lens satisfies the following relationship:

4.6<f3/f<21.1；……(3)

wherein f3 is the focal length of the third lens, and f is the focal length of the optical lens.

Under the condition of satisfying the relation (3), because the light is emitted from the first lens and the second lens with refractive power, and the marginal light is incident on the image surface to easily generate a larger field region, the third lens with positive refractive power is arranged, so that the light can be converged, the marginal aberration can be corrected, and the imaging resolution can be improved; if the upper limit of the conditional expression (3) is exceeded, the focal length of the third lens element is too large, and the bending force is insufficient, so that the occurrence of high-order aberration due to the light beam around the imaging region is not easily suppressed, and if the lower limit of the conditional expression (3) is exceeded, the focal length of the third lens element is too small, and the bending force is too strong, so that large aberration is generated, and the imaging quality is reduced. In some embodiments, the optical lens satisfies the following relationship:

4.3<Rs4/SAGs4≤12.3；……(4)

the Rs4 is a curvature radius of the image-side surface of the fourth lens element at the optical axis, and the sag 4 is a distance from the maximum clear aperture of the image-side surface of the fourth lens element to an intersection point of the image-side surface of the fourth lens element and the optical axis in the optical axis direction.

Under the condition of satisfying the relation (4), the curvature radius value of the image-side surface of the fourth lens element at the optical axis influences the refractive power strength of the fourth lens element, the more the image-side surface is curved, the more the light beam is favorably contracted, and the light beam is refracted to the image plane for focusing through the rear lens element, and by satisfying the relation (4), the astigmatism phenomenon generated by the refraction of the light beam through the surface of the front lens element is favorably corrected while the refractive power strength of the fourth lens element is ensured, and the increase of the processing difficulty of the lens element caused by the excessively curved image-side surface of the fourth lens element is avoided. If the upper limit of the relation (4) is exceeded, the refractive power of the fourth lens element is insufficient, and the aberration correction is insufficient; on the contrary, when the lower limit of the relation (4) is exceeded, the image side surface of the fourth lens is too curved, the processing difficulty of the lens is increased, and the problems of glass breakage and the like occur in the lens forming process.

In some embodiments, the optical lens satisfies the following relationship:

6.3<(D23+CT3+D34)/CT2<9.5；……(5)

wherein D23 is an air space on the optical axis from the image-side surface of the second lens element to the object-side surface of the third lens element, CT3 is a center thickness of the third lens element on the optical axis, D34 is an air space on the optical axis from the image-side surface of the third lens element to the object-side surface of the fourth lens element, and CT2 is a center thickness of the second lens element on the optical axis.

Under the condition of satisfying the relation (5), the aberration of the optical lens is favorably corrected, the imaging resolution is improved, and meanwhile, the compact structure of the optical lens is ensured, and the miniaturization characteristic is satisfied; exceeding the range of relation (5) does not facilitate the correction of the aberration of the optical lens, thereby reducing the imaging quality; meanwhile, the arrangement of the excessive air space and the thickness of the lens can increase the total length burden of the optical lens, which is not beneficial to the miniaturization of the optical lens.

In some embodiments, the optical lens satisfies the following relationship:

-22<f56/f<-8；………(6)

wherein f56 is a combined focal length of the fifth lens and the sixth lens, and f is a focal length of the optical lens.

Under the condition of satisfying the above relation (6), the fifth lens element provides positive refractive power for the optical lens, and the sixth lens element provides negative refractive power for the optical lens, which is beneficial to the mutual correction of aberration by using a structure in which two lenses with positive and negative refractive powers are cemented together. If the refractive power exceeds the lower limit of the relation (6), the refractive power of the cemented lens combination is too small, which is likely to generate larger edge aberration and chromatic aberration, and is not beneficial to improving the resolution performance; when the upper limit of the relation (6) is exceeded, the focal length of the cemented lens assembly is too large, and the total refractive power of the fifth lens element and the sixth lens element is too strong, so that the lens assembly is prone to generate a relatively serious astigmatism phenomenon, which is not favorable for improving the imaging quality.

In some embodiments, the optical lens satisfies the following relationship:

5<Rs7/SAGs7<10；……(7)

wherein Rs7 is a curvature radius of the object-side surface of the seventh lens element at the optical axis, and sag 7 is a distance in the optical axis direction from the maximum clear aperture of the object-side surface of the seventh lens element to an intersection point of the image-side surface of the seventh lens element and the optical axis.

Under the condition of satisfying the relation (7), the curvature radius value of the object-side surface of the seventh lens element at the optical axis influences the refractive power strength of the seventh lens element, and the more the object-side surface of the seventh lens element is curved, the more the contraction of the light beam is facilitated, and by satisfying the relation (7), the astigmatism generated by the refraction of the light beam on the surface of the front lens element can be effectively corrected while the refractive power strength of the seventh lens element is ensured, and the difficulty in processing the lens element caused by the excessively curved object-side surface of the seventh lens element can be avoided. If the upper limit of the relation (7) is exceeded, the refractive power of the seventh lens element is insufficient, and the aberration correction is insufficient; on the contrary, when the lower limit of the relation (7) is exceeded, the image side surface of the seventh lens is too curved, so that the processing difficulty of the lens is increased, and the problems of glass breakage and the like easily occur in the aspheric surface process forming process.

In some embodiments, the optical lens satisfies the following relationship:

2.8<TTL/d17<4.6；……(8)

wherein TTL is the total length of the optical lens, and d17 is the sum of the air spaces on the optical axis between the first lens element and the seventh lens element.

When the relation (8) is satisfied, the total optical length of the optical lens is controlled by limiting the relation between the total optical length and the focal length of the optical lens, thereby satisfying the characteristic of miniaturization of the optical lens. Exceeding the upper limit of the relation (8), the total length of the optical lens is too long, which is not beneficial to miniaturization; if the optical lens focal length is too long in excess of the lower limit of the relation (8), it is not favorable to satisfy the field angle range of the optical lens, and sufficient object space information cannot be obtained.

In some embodiments, the optical lens satisfies the following relationship:

Nd2>1.4,Vd2>80,Nd7>1,Vd7>60；……(9)

wherein Nd2 is a d-light refractive index of the second lens, Nd7 is a d-light refractive index of the seventh lens, Vd2 is a d-light dispersion coefficient of the second lens, and Vd7 is a d-light dispersion coefficient of the seventh lens, and the wavelength of the d-light is 587.6 nm.

Under the condition of satisfying the relation (9), the refractive index and dispersion coefficient of the d light of the second lens and the seventh lens are reasonably set, so that chromatic aberration of the optical lens can be better corrected, and the color reduction capability of the optical lens can be improved; if the relation (9) is exceeded, the optical lens is not favorable for correcting chromatic aberration, so that the optical imaging system is easy to have the problem of purple fringing and other color distortions.

The camera module according to an embodiment of the present invention includes the optical lens according to any one of the above embodiments and a photosensitive element disposed on an image side of the optical lens.

In the camera module of the embodiment of the present application, the value obtained by multiplying the difference between the central thickness of the fifth lens element on the optical axis and the central thickness of the sixth lens element on the optical axis by the difference between the thermal expansion coefficient of the fifth lens element at-30 ℃ to 70 ℃ and the thermal expansion coefficient of the sixth lens element at-30 ℃ to 70 ℃ is 6.7 to 11.7, and the influence of temperature on the lens is reduced by reasonable material matching, and the central thickness difference and the material characteristic difference between the fifth lens element and the sixth lens element of the camera module of the embodiment of the present invention are reduced, so that the lens maintains good imaging quality at high temperature or low temperature.

The electronic device comprises a shell and the camera module, wherein the camera module is arranged on the shell.

In the electronic device of the embodiment of the present invention, the value obtained by multiplying the difference between the central thickness of the fifth lens element on the optical axis and the central thickness of the sixth lens element on the optical axis by the difference between the thermal expansion coefficient of the fifth lens element at-30 ℃ to 70 ℃ and the thermal expansion coefficient of the sixth lens element at-30 ℃ to 70 ℃ is 6.7 to 11.7, and the influence of temperature on the lens is reduced by reasonably matching materials, and the central thickness difference and the material characteristic difference between the fifth lens element and the sixth lens element of the camera module of the embodiment of the present invention are reduced, so that the lens maintains good imaging quality at high temperature or low temperature.

Additional aspects and advantages of embodiments of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of an optical lens according to a first embodiment of the present application;

fig. 2 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of an optical lens according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of an optical lens according to a second embodiment of the present application;

fig. 4 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of the optical lens according to the second embodiment of the present application;

fig. 5 is a schematic structural diagram of an optical lens according to a third embodiment of the present application;

fig. 6 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of an optical lens according to a third embodiment of the present application;

fig. 7 is a schematic structural diagram of an optical lens according to a fourth embodiment of the present application;

fig. 8 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of an optical lens according to a fourth embodiment of the present application;

fig. 9 is a schematic structural diagram of an optical lens according to a fifth embodiment of the present application;

fig. 10 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of an optical lens according to a fifth embodiment of the present application;

fig. 11 is a schematic structural diagram of a camera module according to an embodiment of the present application;

fig. 12 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or uses of other materials.

Referring to fig. 1, an optical lens 10 according to the present invention includes, from an object side to an image side, a first lens element L1 with negative refractive power, a second lens element L2 with negative refractive power, a third lens element L3 with positive refractive power, a fourth lens element L4 with positive refractive power, a fifth lens element L5 with positive refractive power, a sixth lens element L6 with negative refractive power, and a seventh lens element L7 with positive refractive power.

The first lens L1 has an object-side surface S1 and an image-side surface S2. The second lens L2 has an object-side surface S3 and an image-side surface S4. The third lens element L3 has an object-side surface S5 and an image-side surface S6, and the object-side surface S5 of the third lens element L3 is convex in the vicinity of the optical axis. The fourth lens L4 has an object-side surface S8 and an image-side surface S9. The fifth lens L5 has an object-side surface S10 and an image-side surface. The sixth lens L6 has an object-side surface S11 and an image-side surface S12, and the object-side surface S11 and the image-side surface S12 of the sixth lens L6 are both concave in the vicinity of the optical axis. The seventh lens element L7 has an object-side surface S13 and an image-side surface S14, and both the object-side surface S13 and the image-side surface S14 of the seventh lens element L7 are convex in the vicinity of the optical axis.

In some embodiments, the optical lens 10 further includes a diaphragm T1. The stop T1 is disposed between the third lens L3 and the fourth lens L4. Of course, in other embodiments, the stop may be disposed at other positions, for example, the stop T1 may be disposed on the surface of any one of the lenses, or before the first lens L1, or between any two of the lenses, or between the seventh lens L7 and the photosensitive element 20. The specific position of the diaphragm T1 may be set according to practical situations, and is not limited herein. The optical lens 10 can better control the light entering amount through reasonable setting of the position of the diaphragm T1, so that the imaging effect is improved, and the imaging quality of the optical lens 10 is improved.

When the optical lens 10 is used for imaging, light rays emitted or reflected by the subject OBJ enter the optical lens 10 from the object side direction, pass through the first lens L1, the second lens L2, the third lens L3, the stop T1, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, the filter L8, and the protective glass L9, and finally converge on the imaging surface S19.

Further, the optical lens 10 satisfies the following relational expression:

6.7(mm*10^-6/℃)<(CT5-CT6)*(α5-α6)<11.7(mm*10^-6/℃)；……(1)

wherein, CT5 is the central thickness of the fifth lens on the optical axis, CT6 is the central thickness of the sixth lens on the optical axis, α 5 is the thermal expansion coefficient of the fifth lens under the condition of-30 ℃ to 70 ℃, α 6 is the thermal expansion coefficient of the sixth lens under the condition of-30 ℃ to 70 ℃, and the unit is 10^-6/℃。

That is, (CT5-CT6) (. alpha.5-a.6) may be any value in the interval (6.7,11.7) in (mm 10)^-6/° c). For example, the value is 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, etc.

In the optical lens 10 according to the embodiment of the present invention, the value obtained by multiplying the difference between the central thickness of the fifth lens L5 on the optical axis and the central thickness of the sixth lens L6 on the optical axis by the difference between the thermal expansion coefficient of the fifth lens L5 at-30 ℃ to 70 ℃ and the thermal expansion coefficient of the sixth lens L6 at-30 ℃ to 70 ℃ is 6.7 to 11.7, and the influence of temperature on the lens is reduced by reasonably matching materials, and the central thickness difference and the material characteristic difference between the fifth lens L5 and the sixth lens L6 of the camera module according to the embodiment of the present invention are reduced, so that the optical lens 10 maintains good imaging quality at high temperature or low temperature.

In some embodiments, the optical lens 10 satisfies the following relationship:

11.5mm<f1*f2/f<17.7mm；……(2)

where f1 is the focal length of the first lens L1, f2 is the focal length of the second lens L2, and f is the focal length of the optical lens 10.

That is, f1 × f2/f may be any value in the interval (11.5,17.7) in mm. For example, the values are taken to be 11.9, 12.3, 12.7, 13.1, 13.5, 13.9, 14.3, 14.7, 15.1, 15.5, 15.9, 16.3, 16.7, 17.1, 17.5, etc.

When the above relation (2) is satisfied, the first lens element L1 provides negative refractive power for the optical lens, and the negative lens element is disposed on the side close to the object to provide negative refractive power for the optical lens 10, so as to capture light rays incident into the optical lens 10 at a large angle and expand the field angle range of the optical lens 10; the second lens element L2 is configured as a negative lens element to provide negative refractive power for the optical lens 10, which is beneficial to widening the light width, so that the light rays which are incident after being refracted by the first lens element L1 are further widened and fully transmitted to the high-pixel imaging surface, thereby obtaining a wider field range and being beneficial to realizing the high-pixel characteristic of the lens 10; if the upper limit of the relation (2) is exceeded, the combined focal length of the first lens element L1 and the second lens element L2 is large, the overall refractive power is small, and light rays cannot be well converged; if the value exceeds the lower limit of the relation (2), the combined focal length of the first lens element L1 and the second lens element L2 is small, the total refractive power is large, high-order aberration is likely to occur, and the suppression of chromatic aberration is not facilitated.

In some embodiments, the optical lens 10 satisfies the following relationship:

4.6<f3/f<21.1；……(3)

where f3 is the focal length of the third lens element L3, and f is the focal length of the optical lens assembly 10.

That is, f3/f may be any value in the interval (4.6,21.1), for example, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20.4, 20.8, 21, etc.

Under the condition of satisfying the relation (3), since the light is emitted from the first lens element L1 and the second lens element L2 with refractive power, and the edge light is incident on the image plane to easily generate a large field region, the arrangement of the third lens element L3 with positive refractive power is beneficial to converging light, correcting edge aberration, and improving imaging resolution; if the upper limit of the conditional expression (3) is exceeded, the focal length of the third lens element is too large and the bending force is insufficient, so that the occurrence of high-order aberration due to the light beam around the imaging region is not easily suppressed, and if the lower limit of the conditional expression (3) is exceeded, the focal length of the third lens element is too small and the bending force is too strong, so that large aberration is generated and the imaging quality is degraded.

In some embodiments, the optical lens 10 satisfies the following relationship:

4.3<Rs4/SAGs4≤12.3；……(4)

wherein Rs4 is the radius of curvature of the image-side surface S8 of the fourth lens L4, and sag 4 is the distance in the optical axis direction from the maximum clear aperture of the image-side surface S8 of the fourth lens L4 to the intersection point of the image-side surface S8 of the fourth lens L4 and the optical axis.

That is, the Rs4/SAGs4 may have any value in the interval (4.3, 12.3), for example, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.3, etc.

When the above relation (4) is satisfied, the curvature radius value of the image-side surface S8 of the fourth lens element L4 at the optical axis affects the refractive power of the fourth lens element L4, and the more curved the image-side surface S9 is, the more favorable the shrinkage of the light beam is, and the light beam is refracted by the rear lens element to the image plane for focusing, so that the relation (4) is satisfied, which is favorable for effectively correcting the astigmatism caused by the refraction of the light beam by the front lens element surface while ensuring the refractive power of the fourth lens element L4, and at the same time, avoiding the processing difficulty of the lens element from being increased due to the too curved image-side surface S9 of the fourth lens element L4. If the upper limit of the relation (4) is exceeded, the refractive power of the fourth lens element L4 is insufficient, and the aberration correction is insufficient; on the contrary, if the lower limit of the relation (4) is exceeded, the image-side surface S9 of the fourth lens L4 is too curved, which increases the difficulty of processing the lens and causes problems such as glass breakage during the lens molding process.

In some embodiments, the optical lens 10 satisfies the following relationship:

6.3<(D23+CT3+D34)/CT2<9.5；……(5)

wherein D23 is an air space on the optical axis from the image-side surface S4 of the second lens element L2 to the object-side surface S5 of the third lens element L3, CT3 is a central thickness on the optical axis of the third lens element L3, D34 is an air space on the optical axis from the image-side surface S6 of the third lens element L3 to the object-side surface S7 of the fourth lens element L4, and CT2 is a central thickness on the optical axis of the second lens element L2.

That is, (D23+ CT3+ D34)/CT2 may be any value in the interval (6.3, 9.5), for example, 6.5, 6.7, 6.9, 7.1, 7.3, 7.5, 7.7, 7.9, 8.1, 8.3, 8.5, 8.7, 8.9, 9.1, 9.3, 9.4, etc.

Under the condition of satisfying the relation (5), the aberration of the optical lens 10 is favorably corrected, the imaging resolution is improved, and meanwhile, the compact structure of the optical lens 10 is ensured, and the miniaturization characteristic is satisfied; exceeding the range of relation (5) is not favorable for correcting the aberration of the optical lens 10, thereby reducing the imaging quality; meanwhile, the arrangement of the excessive air space and the thickness of the lens increases the overall length burden of the optical lens 10, which is not favorable for the miniaturization of the optical lens 10.

In some embodiments, the optical lens 10 satisfies the following relationship:

-22<f56/f<-8；……(6)

where f56 is the combined focal length of the fifth lens element L5 and the sixth lens element L6, and f is the focal length of the optical lens assembly 10.

That is, f56/f can be any value within the interval (-22, -8), for example, the values are-21, -20.5, -20, -19.5, -19, -18.5, -18, -17.5, -17, 16.5, -16, -15.5, -15, -14.5, -14, -13.5, -13, -12.5, -12, -11.5, -11, -10.5, -10, -9, -8.5, -8, etc.

In the case of satisfying the above relation (6), the fifth lens element L5 provides positive refractive power for the optical lens system 10, and the sixth lens element L6 provides negative refractive power for the optical lens system 10, which is beneficial to mutual correction of aberration by using a structure in which two lens elements with positive and negative refractive powers are cemented together. If the refractive power exceeds the lower limit of the relation (6), the refractive power of the cemented lens combination is too small, which is likely to generate larger edge aberration and chromatic aberration, and is not beneficial to improving the resolution performance; when the upper limit of the relation (6) is exceeded, the focal length of the cemented lens assembly is too large, and the total refractive power of the fifth lens element L5 and the sixth lens element L6 is too strong, so that the lens assembly is prone to generate a relatively severe astigmatism phenomenon, which is not favorable for improving the imaging quality.

In some embodiments, the optical lens 10 satisfies the following relationship:

5<Rs7/SAGs7<10；……(7)

wherein Rs7 is a curvature radius of the object-side surface S13 of the seventh lens L7 at the optical axis, and sag 7 is a distance in the optical axis direction from the maximum clear aperture of the object-side surface S13 of the seventh lens L7 to the intersection point of the image-side surface S14 of the seventh lens L7 and the optical axis.

That is to say, Rs7/SAGs7 is any value in the interval (5,10), for example, 5.3, 5.6, 5.9, 6, 6.3, 6.6, 6.9, 7, 7.3, 7.6, 7.9, 8, 8.3, 8.6, 8.9, 9, 9.1, 9.3, 9.6, 9.9, etc.

When the above-mentioned relation (7) is satisfied, the curvature radius value of the object-side surface S13 of the seventh lens element L7 at the optical axis affects the refractive power strength of the seventh lens element L7, and the more the object-side surface S13 is curved, the more the shrinkage of the light beam is facilitated, so that the relation (7) is satisfied, which is beneficial to effectively correct the astigmatism caused by the refraction of the light beam by the front lens element surface while ensuring the refractive power strength of the seventh lens element L7, and simultaneously, the difficulty in processing the lens element due to the excessive bending of the object-side surface S13 of the seventh lens element L7 is avoided. If the upper limit of the relation (7) is exceeded, the refractive power of the seventh lens element L7 is insufficient, and the aberration correction is insufficient; on the contrary, when the lower limit of the relation (7) is exceeded, the object side surface S13 of the seventh transparent mirror image L7 is too curved, which increases the processing difficulty of the lens and causes the problems of glass breakage and the like in the aspheric surface process forming process.

In some embodiments, the optical lens 10 satisfies the following relationship:

2.8<TTL/d17<4.6；……(8)

where TTL is the total length of the optical lens 10, and d17 is the sum of the air intervals on the optical axis between the first lens L1 and the seventh lens L7.

That is, TTL/d17 is an arbitrary value in the interval (2.8,4.6), for example, values of 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, etc.

When the above-described relational expression (8) is satisfied, the optical total length of the optical lens 10 is controlled by defining the relationship between the optical total length of the optical lens 10 and the focal length of the optical lens 10, and the characteristic of downsizing the optical lens 10 is satisfied. Exceeding the upper limit of the relation (8), the total length of the optical lens 10 is too long, which is not beneficial to miniaturization; if the focal length of the optical lens 10 is too long beyond the lower limit of the relation (8), it is not favorable to satisfy the field angle range of the optical lens 10, and sufficient object space information cannot be obtained.

In some embodiments, the optical lens 10 satisfies the following relationship:

Nd2>1.4,Vd2>80,Nd7>1.6,Vd7>60；……(9)

wherein Nd2 is the d-light refractive index of the second lens, Nd7 is the d-light refractive index of the seventh lens, Vd2 is the d-light dispersion coefficient of the second lens, Vd7 is the d-light dispersion coefficient of the seventh lens, and the wavelength of the d light is 587.6 nm.

Under the condition of satisfying the relation (9), the refractive index and the dispersion coefficient of the d light of the second lens L2 and the seventh lens L7 are reasonably set, so that chromatic aberration of the optical lens 10 can be better corrected, and the color restoration capability of the optical lens 10 can be improved; if the relation (9) is exceeded, the chromatic aberration is not corrected by the optical lens 10, so that the optical imaging system is prone to color distortion such as purple fringing.

In some embodiments, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are all made of glass. The infrared filter L8 is also made of glass, but in other embodiments, the infrared filter L8 may be made of other materials. The specific setting can be according to the actual conditions. And are not limited herein.

Since the first lens element L1 to the seventh lens element L7 are all glass lenses, the optical lens system 10 can effectively eliminate aberrations, meet the requirement of high pixels, and reduce the thickness and air space of each lens element on the optical axis, thereby achieving a balance between miniaturization and compactness and high pixels.

In some embodiments, at least one surface of at least one lens in the optical lens 10 is aspheric. For example, in the embodiment of the present invention, the object-side surface S1 and the image-side surface S2 of the first lens L1 are spherical, the object-side surface S3 and the image-side surface S4 of the second lens L2 are aspherical, the object-side surface S5 and the image-side surface S6 of the third lens L3 are spherical, the object-side surface S8 and the image-side surface S9 of the fourth lens L4 are spherical, the object-side surface S10 and the image-side surface S8749 of the fifth lens L5 are spherical, the object-side surface S11 and the image-side surface S12 of the sixth lens L6 are spherical, the object-side surface S13 and the image-side surface S14 of the seventh lens L7 are aspherical, the object-side surface S15 and the image-side surface S15 of the infrared filter L8 are spherical, and the object-side surface S15 and the image-side surface S36.

That is, the first lens L1, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are all spherical mirrors, the infrared filter L8 is also a spherical mirror, and the second lens L2 and the seventh lens L7 are aspheric mirrors.

The aspherical surface has a surface shape determined by the following formula:

where Z is the longitudinal distance between any point on the aspheric surface and the surface vertex, r is the distance between any point on the aspheric surface and the optical axis, c is the vertex curvature (the reciprocal of the radius of curvature), k is the conic constant, and Ai is the correction coefficient of the ith order of the aspheric surface.

Thus, the optical lens 10 can effectively reduce the total length of the optical lens 10 by adjusting the curvature radius and the aspheric coefficient of each lens surface, and can effectively correct the aberration of the optical lens 10 to improve the imaging quality.

The first embodiment is as follows:

referring to fig. 1, in the first embodiment, the first lens element L1 has negative refractive power, the second lens element L2 has negative refractive power, the third lens element L3 has positive refractive power, the fourth lens element L4 has positive refractive power, the fifth lens element L5 has positive refractive power, the sixth lens element L6 has negative refractive power, and the seventh lens element L7 has positive refractive power.

The object-side surface S1 is convex and the image-side surface S2 is concave. Object side S3 is concave and image side S4 is concave. The object-side surface S5 is convex and the image-side surface S6 is planar. The object-side surface S8 is convex, and the image-side surface S9 is convex. The object-side surface S10 is a convex surface, and the image-side surface of the fifth lens element L5 is a convex surface. Object side S11 is concave and image side S12 is concave. The object-side surface S13 is convex, and the image-side surface S14 is convex.

Referring to fig. 2, the optical lens 10 satisfies the following conditions in table 1:

TABLE 1

In table 1, f is the focal length of the optical lens 10; FNO is the f-number of the optical lens 10; the FOV is the field angle of the optical lens 10. Wherein the units of the Y radius (curvature radius), the thickness and the focal length are mm. In the first embodiment of the present application, the reference wavelength of the focal length is 546.074nm, and the reference wavelength of the refractive index and the abbe number is 587.6 nm.

TABLE 2

The conic coefficients K and the even-order correction coefficients Ai of the aspherical surfaces S3, S4, S13 and S14 of the optical lens 10 are listed in table 2 above, and are derived from the above-mentioned aspherical surface formula (10).

Fig. 2 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of the optical lens 10 according to an embodiment of the present application;

the abscissa of the spherical aberration graph represents the focus offset, and the ordinate represents the normalized field of view, and when the wavelengths given in fig. 2a are 656.2725nm, 587.5618nm, 546.0740nm, 486.1327nm, and 435.8343nm, respectively, the focus offsets of different fields of view are all within ± 0.05mm, which indicates that the optical lens 10 in this embodiment has a small spherical aberration and good imaging quality.

The abscissa of the astigmatism graph represents the focus offset, the ordinate represents the field angle, and the astigmatism curve given in fig. 2b represents that the focus offsets of the sagittal image plane and the meridional image plane are within ± 0.1mm when the wavelength is 546.0740nm, which indicates that the optical lens 10 in the present embodiment has small astigmatism and good imaging quality.

The abscissa of the distortion curve graph represents the distortion rate, the ordinate represents the field angle, and the distortion curve given in fig. 2c represents that when the reference wavelength is 546.0740nm, the maximum half-field angle is 87.1 degrees, and the distortions are all less than 100%, which indicates that the distortion of the optical lens 10 in this embodiment is better corrected and the imaging quality is better.

Example two:

referring to fig. 3, in the second embodiment, the first lens element L1 has negative refractive power, the second lens element L2 has negative refractive power, the third lens element L3 has positive refractive power, the fourth lens element L4 has positive refractive power, the fifth lens element L5 has positive refractive power, the sixth lens element L6 has negative refractive power, and the seventh lens element L7 has positive refractive power.

The object-side surface S1 is convex and the image-side surface S2 is concave. Object side S3 is concave and image side S4 is concave. The object-side surface S5 is convex and the image-side surface S6 is concave. The object-side surface S8 is convex, and the image-side surface S9 is convex. The object-side surface S10 is a convex surface, and the image-side surface of the fifth lens element L5 is a convex surface. Object side S11 is concave and image side S12 is concave. The object-side surface S13 is convex, and the image-side surface S14 is convex.

Referring to fig. 10, the optical lens 10 satisfies the following table conditions:

TABLE 3

In table 3, f is the focal length of the optical lens 10; FNO is the f-number of the optical lens 10; the FOV is the field angle of the optical lens 10. Wherein the units of the Y radius (curvature radius), the thickness and the focal length are mm. In the second embodiment, the reference wavelength of the focal length is 546.074nm, and the reference wavelength of the refractive index and the abbe number is 587.6 nm.

TABLE 4

The conic coefficients K and the even-order correction coefficients Ai of the aspherical surfaces S3, S4, S13 and S14 of the optical lens 10 are listed in table 4 above, and are derived from the above-mentioned aspherical surface formula (10).

Fig. 4 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of the optical lens 10 according to the second embodiment of the present application;

the abscissa of the spherical aberration graph represents the focus offset, the ordinate represents the normalized field of view, and the focus offsets of different fields of view are all within-0.1 mm-0.05mm when the wavelengths given in fig. 4a are 656.2725nm, 587.5618nm, 546.0740nm, 486.1327nm, and 435.8343nm, respectively, which illustrates that the optical lens 10 in this embodiment has small spherical aberration and good imaging quality.

The abscissa of the astigmatism graph represents the focus offset, the ordinate represents the field angle, and the astigmatism curve given in fig. 4b represents that the focus offsets of the sagittal image plane and the meridional image plane are both within ± 0.05mm when the wavelength is 546.0740nm, which indicates that the optical lens 10 in the present embodiment has small astigmatism and good imaging quality.

The abscissa of the distortion curve graph represents the distortion rate, the ordinate represents the field angle, and the distortion curve given in fig. 4c represents that when the reference wavelength is 546.0740nm, the maximum half-field angle is 87 degrees, and the distortions are all less than 100%, which indicates that the distortion of the optical lens 10 in this embodiment is better corrected and the imaging quality is better.

Example three:

referring to fig. 5, in the third embodiment, the first lens element L1 has negative refractive power, the second lens element L2 has negative refractive power, the third lens element L3 has positive refractive power, the fourth lens element L4 has positive refractive power, the fifth lens element L5 has positive refractive power, the sixth lens element L6 has negative refractive power, and the seventh lens element L7 has positive refractive power.

Referring to fig. 6, the optical lens 10 satisfies the following table conditions:

TABLE 5

In table 5, f is the focal length of the optical lens 10; FNO is the f-number of the optical lens 10; the FOV is the field angle of the optical lens 10; wherein the units of the Y radius (curvature radius), the thickness and the focal length are mm. In the third embodiment of the present application, the reference wavelength of the focal length is 546.074nm, and the reference wavelength of the refractive index and the abbe number is 587.6 nm.

TABLE 6

The conic coefficients K and the even-order correction coefficients Ai of the aspherical surfaces S3, S4, S13 and S14 of the optical lens 10 are listed in table 6 above, and are derived from the above-mentioned aspherical surface formula (10).

Fig. 6 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of the optical lens 10 according to the third embodiment of the present application;

the abscissa of the spherical aberration curve represents the focus offset, the ordinate represents the normalized field of view, and the focus offsets of different fields of view are all within-0.1 mm to 0.05mm when the wavelengths given in fig. 6a are 656.2725nm, 587.5618nm, 546.0740nm, 486.1327nm, and 435.8343nm, respectively, which illustrates that the optical lens 10 in this embodiment has small spherical aberration and good imaging quality.

The abscissa of the astigmatism graph represents the focus offset, the ordinate represents the field angle, and the astigmatism curve given in fig. 6b represents that the focus offsets of the sagittal image plane and the meridional image plane are both within-0.05 mm to 0.2mm when the wavelength is 546.0740nm, which shows that the optical lens 10 in this embodiment has less astigmatism and better imaging quality.

The abscissa of the distortion curve graph represents the distortion rate, the ordinate represents the field angle, and the distortion curve given in fig. 6c represents that when the reference wavelength is 546.0740nm, the maximum half-field angle is 87 degrees, and the distortions are all less than 100%, which indicates that the distortion of the optical lens 10 in this embodiment is better corrected and the imaging quality is better.

Example four:

referring to fig. 7, in the fourth embodiment, the first lens element L1 has negative refractive power, the second lens element L2 has negative refractive power, the third lens element L3 has positive refractive power, the fourth lens element L4 has positive refractive power, the fifth lens element L5 has positive refractive power, the sixth lens element L6 has negative refractive power, and the seventh lens element L7 has positive refractive power.

Referring to fig. 8, the optical lens 10 satisfies the following table conditions:

TABLE 7

In table 5, f is the focal length of the optical lens 10; FNO is the f-number of the optical lens 10; the FOV is the field angle of the optical lens 10; wherein the units of the Y radius (curvature radius), the thickness and the focal length are mm. In the fourth embodiment of the present application, the reference wavelength of the focal length is 546.074nm, and the reference wavelength of the refractive index and the abbe number is 587.6 nm.

TABLE 8

The conic coefficients K and the even-order correction coefficients Ai of the aspherical surfaces S3, S4, S13 and S14 of the optical lens 10 are listed in table 8 above, and are derived from the above-mentioned aspherical surface formula (10).

Fig. 8 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of the optical lens 10 according to the fourth embodiment of the present application;

the abscissa of the spherical aberration graph represents the focus offset, the ordinate represents the normalized field of view, and the focus offsets of different fields of view are all within-0.05 mm to 0.05mm when the wavelengths given by a in fig. 8 are 656.2725nm, 587.5618nm, 546.0740nm, 486.1327nm, and 435.8343nm, respectively, which illustrates that the optical lens 10 in this embodiment has small spherical aberration and good imaging quality.

The abscissa of the astigmatism graph represents the focus offset, the ordinate represents the field angle, and the astigmatism curve given in fig. 8b represents that the focus offsets of the sagittal image plane and the meridional image plane are within ± 0.05mm when the wavelength is 546.0740nm, which shows that the optical lens 10 in the present embodiment has small astigmatism and good imaging quality.

The abscissa of the distortion curve graph represents the distortion rate, the ordinate represents the field angle, and the distortion curve given in fig. 8c represents that when the reference wavelength is 546.0740nm, the maximum half-field angle is 87.1 degrees, and the distortions are all less than 100%, which indicates that the distortion of the optical lens 10 in this embodiment is better corrected and the imaging quality is better.

Example five:

referring to fig. 9, in the fifth embodiment, the first lens element L1 has negative refractive power, the second lens element L2 has negative refractive power, the third lens element L3 has positive refractive power, the fourth lens element L4 has positive refractive power, the fifth lens element L5 has positive refractive power, the sixth lens element L6 has negative refractive power, and the seventh lens element L7 has positive refractive power.

TABLE 9

In table 9, f is the focal length of the optical lens 10; FNO is the f-number of the optical lens 10; the FOV is the field angle of the optical lens 10; wherein the units of the Y radius (curvature radius), the thickness and the focal length are mm. In the fifth embodiment, the reference wavelength of the focal length is 546.074nm, and the reference wavelength of the refractive index and the abbe number is 587.6 nm.

Watch 10

The conic coefficients K and the even-order correction coefficients Ai of the aspherical surfaces S3, S4, S13 and S14 of the optical lens 10 are listed in table 10 above, and are derived from the above-mentioned aspherical surface formula (10).

Fig. 10 is a longitudinal spherical aberration graph, an astigmatism graph, and a distortion graph of the optical lens 10 according to the fifth embodiment of the present application;

the abscissa of the spherical aberration curve represents the focus offset, the ordinate represents the normalized field of view, and when the wavelengths given in fig. 10a are 656.2725nm, 587.5618nm, 546.0740nm, 486.1327nm, and 435.8343nm, respectively, the focus offsets of different fields of view are all within-0.05 mm to 0.05mm, which indicates that the optical lens 10 in this embodiment has small spherical aberration and good imaging quality.

The abscissa of the astigmatism graph represents the focus offset, the ordinate represents the field angle, and the astigmatism curve given in fig. 10b represents that the focus offsets of the sagittal image plane and the meridional image plane are within ± 0.05mm when the wavelength is 546.0740nm, which shows that the optical lens 10 in the present embodiment has small astigmatism and good imaging quality.

The abscissa of the distortion curve graph represents the distortion rate, the ordinate represents the field angle, and the distortion curve given in fig. 10c represents that when the reference wavelength is 546.0740nm, the maximum half-field angle is 87.1 degrees, and the distortions are all less than 100%, which indicates that the distortion of the optical lens 10 in this embodiment is better corrected and the imaging quality is better.

The values in the first to fifth examples for relational expression (1), relational expression (2), relational expression (3), relational expression (4), relational expression (5), relational expression (6), relational expression (7), relational expression (8) and relational expression (9) above are as follows in table 11.

TABLE 11

Referring to fig. 11, a camera module 100 according to an embodiment of the invention includes an optical lens 10 and a photosensitive element 20. The light receiving element 20 is disposed on the image side of the optical lens 10.

The photosensitive element 20 may be a Complementary Metal Oxide Semiconductor (CMOS) photosensitive element 20 or a Charge-coupled Device (CCD) photosensitive element 20.

In the camera module 100 of the present embodiment, the value obtained by multiplying the difference between the central thickness of the fifth lens L5 on the optical axis and the central thickness of the sixth lens L6 on the optical axis by the difference between the thermal expansion coefficient of the fifth lens L5 at-30 ℃ to 70 ℃ and the thermal expansion coefficient of the sixth lens L6 at-30 ℃ to 70 ℃ is 6.7 to 11.7, and the influence of temperature on the lens is reduced by reasonably matching materials, and the central thickness difference and the material characteristic difference between the fifth lens L5 and the sixth lens L6 of the camera module of the present embodiment are reduced, so that the optical lens 10 maintains good imaging quality at high temperature or low temperature.

Referring to fig. 12, an electronic device 1000 according to an embodiment of the invention includes a housing 200 and a camera module 100. The camera module 100 is mounted on the housing 200.

The electronic device 1000 according to the embodiment of the present invention includes, but is not limited to, information terminal devices such as a smart phone (as shown in fig. 12), a mobile phone, a Personal Digital Assistant (PDA), a game machine, a Personal Computer (PC), a camera, a smart watch, and a tablet computer, and home appliances having a photographing function.

In the description herein, references to the description of the terms "one embodiment," "certain embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An optical lens, comprising, in order from an object side to an image side:

a first lens element with negative refractive power;

a second lens element with negative refractive power;

a third lens element with positive refractive power having a convex object-side surface near an optical axis;

a fourth lens element with positive refractive power;

a fifth lens element with positive refractive power;

the sixth lens element with negative refractive power has a concave object-side surface and a concave image-side surface near an optical axis;

the fourth lens element with positive refractive power has a convex object-side surface and a convex image-side surface near an optical axis;

the optical lens also comprises a diaphragm;

the optical lens satisfies the following relation:

6.7(mm*10^-6/℃)<(CT5-CT6)*(α5-α6)<11.7(mm*10^-6/℃)；

2. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

11.5mm<f1*f2/f<17.7mm；

3. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

4.6<f3/f<21.1；

4. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

4.3<Rs4/SAGs4≤12.3；

5. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

6.3<(D23+CT3+D34)/CT2<9.5；

wherein D23 is an air space on the optical axis from the image-side surface of the second lens element to the object-side surface of the third lens element, CT3 is an optical thickness of the third lens element, D34 is an air space on the optical axis from the image-side surface of the third lens element to the object-side surface of the fourth lens element, and CT2 is an optical thickness of the second lens element.

6. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

-22<f56/f<-8；

7. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

5<Rs7/SAGs7<10；

8. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

2.8<TTL/d17<4.6；

9. An optical lens according to claim 1, wherein the optical lens satisfies the following relation:

Nd2>1.4,Vd2>80,Nd7>1,Vd7>60；

10. The utility model provides a camera module which characterized in that, camera module includes:

an optical lens as claimed in any one of claims 1 to 9; and

a light sensing element disposed on an image side of the optical lens.

11. An electronic device, comprising:

a housing; and

the camera module of claim 10, said camera module mounted on said housing.