CN116500765B

CN116500765B - optical lens

Info

Publication number: CN116500765B
Application number: CN202310785751.8A
Authority: CN
Inventors: 章彬炜; 徐文; 曾昊杰
Original assignee: Jiangxi Lianyi Optics Co Ltd
Current assignee: Jiangxi Lianyi Optics Co Ltd
Priority date: 2023-06-30
Filing date: 2023-06-30
Publication date: 2023-10-03
Anticipated expiration: 2043-06-30
Also published as: CN116500765A

Abstract

The invention discloses an optical lens, which sequentially comprises from an object side to an imaging surface along an optical axis: the first lens with positive focal power has a convex object side surface and a concave image side surface; a second lens element with positive refractive power having a convex object-side surface and a concave image-side surface; a third lens element with positive refractive power having a convex object-side surface at a paraxial region and a convex image-side surface; a fourth lens having negative optical power; a fifth lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a sixth lens element with negative refractive power having a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region; the seventh lens element with negative refractive power has a concave object-side surface and a concave image-side surface at a paraxial region. The optical lens has the advantages of large aperture, compact structure and high pixel through reasonable collocation of the shape and focal power of each lens, and can be matched with a sensor chip with large size to realize high-definition imaging.

Description

Optical lens

Technical Field

The invention relates to the technical field of imaging lenses, in particular to an optical lens.

Background

With rapid updating of portable electronic devices, consumers demand higher and higher photographing functions, and higher pixels are pursued. In recent years, after related mobile phone manufacturers start to use a 40M high-pixel lens matched with a 1/1.7 inch large-size sensor chip, each portable electronic equipment manufacturer sequentially pushes out equipment matched with the high-pixel lens of the large-size sensor chip, and nowadays, the high-pixel lens matched with the large-size sensor chip becomes the standard of a flagship machine of each portable electronic equipment manufacturer.

In order to ensure the improvement of the pixels and not to reduce the pixel point size of the sensor chip, the increase of the sensor chip size is an important development trend of high pixels. Therefore, how to develop a high-pixel optical lens with a large-size sensor chip and a small size is a technical problem that needs to be solved by those skilled in the art.

Disclosure of Invention

Therefore, the invention aims to provide an optical lens which has the advantages of large aperture, small volume and high pixel, and can be matched with a sensor chip with a larger size to realize high-definition imaging so as to meet the shooting requirement of consumers.

The embodiment of the invention realizes the aim through the following technical scheme.

The invention provides an optical lens, which sequentially comprises from an object side to an imaging surface along an optical axis: the first lens with positive focal power has a convex object side surface and a concave image side surface; a second lens element with positive refractive power having a convex object-side surface and a concave image-side surface; a third lens element with positive refractive power having a convex object-side surface at a paraxial region and a convex image-side surface; a fourth lens having negative optical power; a fifth lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a sixth lens element with negative refractive power having a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region; a seventh lens element with negative refractive power having a concave object-side surface and a concave image-side surface at a paraxial region; wherein, the optical lens satisfies the conditional expression: 1.7< IH/f <2.0, f represents the effective focal length of the optical lens, and IH represents the image height corresponding to the full field angle of the optical lens.

Compared with the prior art, the optical lens provided by the invention adopts a seven-piece compact structure, and the lens has a larger imaging surface through reasonable collocation of focal power and surface of each lens, so that 1/1.31 inch large-size sensor chip can be matched, and the shooting configuration of the current main stream is satisfied; meanwhile, the optical lens has the characteristic of a large aperture, and the light inlet quantity is more, so that the optical lens has high-definition imaging quality even in a dim environment or strong light; the optical lens also has an ultra-high pixel of 50M, is matched with the optimization of a later-stage algorithm, can output a picture with the pixel level of 108M at the highest, achieves the level of the top in the market, and has stronger market competitiveness.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

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

Fig. 2 is a graph showing a field curvature of an optical lens according to a first embodiment of the present invention.

Fig. 3 is a distortion graph of an optical lens according to a first embodiment of the present invention.

Fig. 4 is an axial chromatic aberration diagram of an optical lens according to a first embodiment of the present invention.

Fig. 5 is a vertical axis chromatic aberration diagram of an optical lens according to a first embodiment of the present invention.

Fig. 6 is a schematic structural diagram of an optical lens according to a second embodiment of the present invention.

Fig. 7 is a field curvature chart of an optical lens according to a second embodiment of the present invention.

Fig. 8 is a distortion graph of an optical lens according to a second embodiment of the present invention.

Fig. 9 is an axial chromatic aberration diagram of an optical lens according to a second embodiment of the present invention.

Fig. 10 is a vertical axis chromatic aberration diagram of an optical lens according to a second embodiment of the present invention.

Fig. 11 is a schematic structural diagram of an optical lens according to a third embodiment of the present invention.

Fig. 12 is a field curve diagram of an optical lens according to a third embodiment of the present invention.

Fig. 13 is a distortion graph of an optical lens according to a third embodiment of the present invention.

Fig. 14 is an axial chromatic aberration diagram of an optical lens according to a third embodiment of the present invention.

Fig. 15 is a vertical axis chromatic aberration diagram of an optical lens according to a third embodiment of the present invention.

Detailed Description

In order that the objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Several embodiments of the invention are presented in the figures. This 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.

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 in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Like reference numerals refer to like elements throughout the specification.

In this context, near the optical axis means the area near the optical axis. If the lens surface is convex and the convex position is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at least in the paraxial region.

The invention provides an optical lens, which sequentially comprises from an object side to an imaging surface along an optical axis: diaphragm, first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens and light filter.

The first lens has positive focal power, the object side surface is a convex surface, and the image side surface is a concave surface.

The second lens has positive focal power, the object side surface is a convex surface, and the image side surface is a concave surface.

The third lens has positive focal power, the object side surface of the third lens is convex at a paraxial region, and the image side surface of the third lens is convex;

the fourth lens element has negative refractive power, wherein an object-side surface of the fourth lens element can be concave or convex, and an image-side surface of the fourth lens element can be concave or convex.

The fifth lens has positive focal power, the object side surface of the fifth lens is concave, and the image side surface of the fifth lens is convex.

The sixth lens element has negative refractive power, wherein an object-side surface thereof is convex at a paraxial region and an image-side surface thereof is concave at the paraxial region.

The seventh lens element has negative refractive power, wherein an object-side surface thereof is concave, and an image-side surface thereof is concave at a paraxial region.

In some embodiments, the optical lens satisfies the following conditional expression: 1.7< IH/f <2.0, wherein f represents the effective focal length of the optical lens, and IH represents the image height corresponding to the full field angle of the optical lens. The lens can keep a larger focal length and has a larger imaging surface, and can be matched with a 1/1.31 inch large-size sensor chip to realize high-definition imaging, so that the shooting configuration of the current mainstream is met.

In some embodiments, the optical lens satisfies the following conditional expression: 1.5< f1/f <4, wherein f1 represents a focal length of the first lens and f represents an effective focal length of the optical lens. The first lens has proper positive focal power, effectively eases the deflection degree of the light entering the system, avoids excessive aberration caused by excessively strong refraction change, is beneficial to more light entering the rear optical system, and increases the luminous flux to realize the large aperture effect of the lens.

In some embodiments, the optical lens satisfies the following conditional expression: 0.4< f1/f2<3, where f1 represents the focal length of the first lens and f2 represents the focal length of the second lens. The lens has the advantages that the focal length ratio of the first lens and the second lens is reasonably set, so that light entering the lens can be effectively prevented from being excessively deflected, the sensitivity of an optical system is reduced, the head size of the lens is reduced (the outer diameter of the head can be smaller than 4 mm), and the size of the lens can be miniaturized.

In some embodiments, the optical lens satisfies the following conditional expression: 0.3< f3/f <3, -8< f4/f < -1 >, wherein f3 represents a focal length of the third lens, f4 represents a focal length of the fourth lens, and f represents an effective focal length of the optical lens. The focal length ratio of the third lens and the fourth lens is reasonably matched, so that the advanced spherical aberration of the lens can be better controlled, the field curvature of the lens is reduced, and the imaging quality of the lens is better improved.

In some embodiments, the optical lens satisfies the following conditional expression: -0.8< f5/f6< -0.25, wherein f5 represents the focal length of the fifth lens and f6 represents the focal length of the sixth lens. The conditions are met, the positive spherical aberration generated by the sixth lens (negative lens) and the negative spherical aberration generated by the fifth lens (positive lens) can be balanced, the overall imaging quality is improved, meanwhile, the light trend can be reasonably controlled, and the problem of overhigh lens sensitivity caused by overlarge light deflection degree is avoided.

In some embodiments, the optical lens satisfies the following conditional expression: 0.9< f5/f <5,1.30< R9/R10<2.35, wherein f5 represents a focal length of the fifth lens element, f represents an effective focal length of the optical lens element, R9 represents a radius of curvature of an object-side surface of the fifth lens element, and R10 represents a radius of curvature of an image-side surface of the fifth lens element. The optical power and the surface shape of the fifth lens can be reasonably distributed to ensure that the fifth lens bears corresponding positive optical power, the deflection efficiency of light rays can be accelerated, and the miniaturization of the lens volume is facilitated.

In some embodiments, the optical lens satisfies the following conditional expression: -6< f6/f < -2,1.5< ct6/ET 6< 2.5, wherein f6 represents the focal length of the sixth lens, f represents the effective focal length of the optical lens, CT6 represents the center thickness of the sixth lens, ET6 represents the edge thickness of the sixth lens. The above conditions are satisfied, and the aberration of the peripheral light is adjusted by adjusting the focal length and the surface shape of the sixth lens, so that the imaging quality of the optical lens is improved.

In some embodiments, the optical lens satisfies the following conditional expression: -2.3< f7/f < -1, wherein f7 represents the focal length of the seventh lens and f represents the effective focal length of the optical lens. The focal length of the seventh lens is reasonably set, so that the focal length efficiency of light on an image surface can be effectively reduced, aberration difference between different wavelengths can be effectively reduced, the correction difficulty of chromatic aberration is reduced, the imaging quality is improved, and meanwhile, the seventh negative lens bears larger light deflection capacity, so that the aberration of the whole system is balanced, and high-pixel imaging of the lens is realized.

In some embodiments, the optical lens satisfies the following conditional expression: 0.5< R1/R2<1,0.2< R2/f <1, wherein R1 represents a radius of curvature of an object side surface of the first lens, R2 represents a radius of curvature of an image side surface of the first lens, and f represents an effective focal length of the optical lens. The above conditions are met, and more luminous fluxes can enter the imaging system by reasonably setting the surface shape of the first lens, so that the large aperture effect of the lens is realized, and the lens has high-definition imaging quality even in a dim environment or in strong light.

In some embodiments, the optical lens satisfies the following conditional expression: 1< R11/R12<4,2< R11/f <5, wherein R11 represents a radius of curvature of an object side surface of the sixth lens, R12 represents a radius of curvature of an image side surface of the sixth lens, and f represents an effective focal length of the optical lens. The surface shape of the sixth lens is reasonably adjusted to be favorable for reducing stray light, meanwhile, the aberration of the marginal view field is effectively improved, the correction difficulty of curvature of field and distortion is reduced, and the overall imaging quality is improved.

In some embodiments, the optical lens satisfies the following conditional expression: 1< R12/R14<3, wherein R12 represents a radius of curvature of an image side surface of the sixth lens, and R14 represents a radius of curvature of an image side surface of the seventh lens. The conditions are met, the surface types of the sixth lens and the seventh lens are reasonably arranged, the light trend can be reasonably controlled, the problem of overhigh lens sensitivity caused by overlarge light deflection degree is avoided, and the imaging performance of the optical lens is improved.

In some embodiments, the optical lens satisfies the following conditional expression: 1.1< TTL/f <1.38,0.6< TTL/IH <0.7, wherein TTL represents the total optical length of the optical lens, f represents the effective focal length of the optical lens, and IH represents the image height corresponding to the full field angle of the optical lens. The conditions are met, the large target surface imaging effect of the optical lens can be realized, the pixel point size can be increased under the same pixel, the energy receiving efficiency of the chip to the light collected by the lens can be increased, and therefore high-pixel imaging is realized; meanwhile, miniaturization of the lens and reasonable equalization of a large image plane can be better realized.

In some embodiments, the optical lens satisfies the following conditional expression: IH/FNo >6.5mm, wherein IH represents the image height corresponding to the full field angle of the optical lens, and FNo represents the f-number of the optical lens. The lens has a larger imaging surface and a large aperture, the luminous flux entering the lens is increased to a certain extent, the influence of noise generated when light is insufficient on an imaging picture is reduced, and the lens has high-definition imaging quality in a dim environment or in strong light.

In some embodiments, the optical lens satisfies the following conditional expression: 0.26< DM1/IH <0.31, wherein DM1 represents the maximum effective caliber of the first lens, and IH represents the image height corresponding to the full field angle of the optical lens. The lens has a larger image surface, can be matched with a sensor chip with the size of 1/1.3 inch, is beneficial to reducing the caliber of the front lens, has a smaller head outer diameter, and better realizes the balance of large image surface imaging and volume miniaturization of the lens.

In some embodiments, the optical lens satisfies the following conditional expression: -2.60< f47/f < -0.50, -2.60< f47/f13 < -0.50, wherein f represents an effective focal length of the optical lens, f13 represents a combined focal length of the first lens to the third lens, and f47 represents a combined focal length of the fourth lens to the seventh lens. The front three lenses (the first lens to the third lens) in the optical system form a positive lens group, the rear four lenses (the fourth lens to the seventh lens) form a negative lens group, the above conditions are met, and various spherical aberration of the lens can be balanced and imaging quality of the lens can be improved by reasonably setting the combined focal length ratio of the front lens group and the rear lens group.

In some embodiments, the optical lens satisfies the following conditional expression: 1.70< f/EPD <1.85, wherein f represents an effective focal length of the optical lens and EPD represents an entrance pupil diameter of the optical lens. The light quantity of the optical lens can be improved, the lens can be normally shot in a dim environment or in strong light, and the effect that the main body highlights the background blurring can be achieved during shooting.

In some embodiments, the optical lens satisfies the following conditional expression: -1< (sag41+sag42)/ET 4<0.5, wherein SAG41 represents the edge sagittal height of the object side of the fourth lens, SAG42 represents the edge sagittal height of the image side of the fourth lens, ET4 represents the edge thickness of the fourth lens. The lens has the advantages that the surface type of the fourth lens is reasonably arranged, so that the deflection trend of light rays is slowed down, the light rays are prevented from imaging at an excessive angle on the image surface, the chromatic aberration and the correction difficulty of spherical aberration of the lens are reduced, and the overall imaging quality is improved.

As an implementation mode, seven lenses in the optical lens can be all plastic lenses or glass-plastic mixed matching, so that good imaging effect can be obtained; in the invention, in order to better reduce the volume of the lens and reduce the cost, seven plastic lens combinations are adopted, and the optical lens structure is more compact and has ultrahigh pixels through specific surface shape collocation and reasonable optical power distribution, so that ultrahigh-definition imaging can be realized by matching with a 1/1.31 inch large-size sensor chip. The first lens to the seventh lens are plastic aspheric lenses, and the aspheric lenses are adopted, so that cost can be effectively reduced, aberration can be corrected, and an optical performance product with higher cost performance can be provided.

The invention is further illustrated in the following examples. In various embodiments, the thickness, radius of curvature, and material selection portion of each lens in the optical lens may vary, and for specific differences, reference may be made to the parameter tables of the various embodiments. The following examples are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following examples, and any other changes, substitutions, combinations or simplifications that do not depart from the gist of the present invention are intended to be equivalent substitutes within the scope of the present invention.

The surface shape of the aspherical lens in each embodiment of the present invention satisfies the following equation:

，

where z is the distance sagittal height from the aspherical surface vertex when the aspherical surface is at a position of height h in the optical axis direction, c is the paraxial curvature of the surface, k is the quadric coefficient, A _2i The aspherical surface profile coefficient of the 2 i-th order.

In the following embodiments, the thickness, radius of curvature, and material selection portion of each lens in the optical lens are different, and specific differences can be seen from the parameter table of each embodiment.

First embodiment

Referring to fig. 1 for a schematic structural diagram of an optical lens 100 according to a first embodiment of the present invention, the optical lens 100 includes, in order from an object side to an imaging surface S17 along an optical axis: stop ST, first lens L1, second lens L2, third lens L3, fourth lens L4, fifth lens L5, sixth lens L6, seventh lens L7, and filter G1.

The first lens element L1 has positive refractive power, wherein an object-side surface S1 of the first lens element is convex, and an image-side surface S2 of the first lens element is concave.

The second lens element L2 has positive refractive power, wherein an object-side surface S3 of the second lens element is convex, and an image-side surface S4 of the second lens element is concave.

The third lens element L3 with positive refractive power has a convex object-side surface S5 at a paraxial region and a convex image-side surface S6;

the fourth lens element L4 has negative refractive power, wherein an object-side surface S7 of the fourth lens element is concave, and an image-side surface S8 of the fourth lens element is convex.

The fifth lens element L5 has positive refractive power, wherein an object-side surface S9 of the fifth lens element is concave, and an image-side surface S10 of the fifth lens element is convex.

The sixth lens element L6 has negative refractive power, wherein an object-side surface S11 of the sixth lens element is convex at a paraxial region thereof and an image-side surface S12 of the sixth lens element is concave at a paraxial region thereof.

The seventh lens L7 has negative optical power, the object-side surface S13 of the seventh lens is concave, and the image-side surface S14 of the seventh lens is concave at a paraxial region.

The object side surface of the filter G1 is S15, and the image side surface is S16.

In the present embodiment, seven lenses in the optical lens 100 are plastic aspheric lenses.

The relevant parameters of each lens in the optical lens 100 provided in this embodiment are shown in table 1.

TABLE 1

The surface profile coefficients of the aspherical surfaces of the optical lens 100 in this embodiment are shown in table 2.

TABLE 2

In the present embodiment, graphs of curvature of field, distortion, axial chromatic aberration, and vertical chromatic aberration of the optical lens 100 are shown in fig. 2, 3, 4, and 5, respectively.

In fig. 2, the field Qu Quxian represents the field curvature of the meridian and sagittal directions at different image heights on the image plane, the abscissa represents the offset (unit: mm), and the ordinate represents the angle of view (unit: degree), and as can be seen from the figure, the field curvature offset of the meridian and sagittal directions on the image plane is controlled within ±0.1 mm, which indicates that the field curvature of the optical lens 100 is well corrected.

In FIG. 3, the distortion curve represents F-Tan (θ) distortion corresponding to different image heights on an image plane, the abscissa represents the distortion magnitude, and the ordinate represents the angle of view (in degrees); as can be seen from the figure, the distortion of the lens is controlled to be within 2% in the full field of view of the lens, indicating that the distortion of the optical lens 100 is well corrected.

The axial chromatic aberration curve in fig. 4 shows the aberration on the optical axis at the imaging plane, the abscissa in the figure shows the offset, and the ordinate shows the normalized pupil radius, and it is known from the figure that the axial chromatic aberration of the shortest wavelength and the maximum wavelength is controlled within ±0.03 mm, which indicates that the axial chromatic aberration of the optical lens 100 is well corrected.

The vertical axis chromatic aberration curves in fig. 5 show chromatic aberration of different image heights of each wavelength with respect to the center wavelength on the image plane, the horizontal axis in the figure shows the vertical axis chromatic aberration value (unit: micrometers) of each wavelength with respect to the center wavelength, and the vertical axis shows the normalized angle of view, and it is known that the chromatic aberration of each wavelength with respect to the center wavelength is controlled within ±2 micrometers in different fields of view, which means that the vertical axis chromatic aberration of the optical lens 100 is well corrected.

Second embodiment

Referring to fig. 6, a schematic diagram of an optical lens 200 according to a second embodiment of the invention is shown, and the optical lens 200 according to the present embodiment is substantially the same as the first embodiment, and is mainly characterized in that an object-side surface S7 of the fourth lens element is convex at a paraxial region, an image-side surface S8 of the fourth lens element is concave, and curvature radius, aspheric coefficients, and thickness of each lens element are different.

The relevant parameters of each lens in the optical lens 200 provided in this embodiment are shown in table 3.

TABLE 3 Table 3

The surface profile coefficients of the aspherical surfaces of the optical lens 200 in this embodiment are shown in table 4.

TABLE 4 Table 4

Referring to fig. 7, 8, 9 and 10, graphs of field curvature, distortion, axial chromatic aberration and vertical chromatic aberration of the optical lens 200 are shown, respectively. As can be seen from fig. 7, the curvature of field is controlled within ±0.1 mm, which indicates that the curvature of field of the optical lens 200 is better corrected. As can be seen from fig. 8, the optical distortion is controlled to be within 2%, which means that the distortion of the optical lens 200 is well corrected. It can be seen from fig. 9 that the axial chromatic aberration of the shortest wavelength and the maximum wavelength is controlled within ±0.06 millimeters, which indicates that the axial chromatic aberration of the optical lens 200 is well corrected. As can be seen from fig. 10, the vertical chromatic aberration at different wavelengths is controlled within ±2.0 microns, indicating that the vertical chromatic aberration of the optical lens 200 is well corrected. As can be seen from fig. 7 to 10, the aberration of the optical lens 200 is well balanced, and has good optical imaging quality.

Third embodiment

Referring to fig. 11 for a schematic structural diagram of an optical lens 300 according to the present embodiment, the optical lens 300 in the present embodiment has a structure substantially the same as that of the optical lens 100 in the first embodiment, except that an image side surface S8 of the fourth lens element is concave at a paraxial region, and a curvature radius, an aspheric coefficient, and a thickness of each lens element are different.

The relevant parameters of each lens in the optical lens 300 provided in this embodiment are shown in table 5.

TABLE 5

The surface profile coefficients of the aspherical surfaces of the optical lens 300 in this embodiment are shown in table 6.

TABLE 6

Referring to fig. 12, 13, 14 and 15, graphs of field curvature, distortion, axial chromatic aberration and vertical chromatic aberration of the optical lens 300 are shown, respectively. From fig. 12, it can be seen that curvature of field is controlled within ±0.1 mm, which indicates that curvature of field correction of the optical lens 300 is good. As can be seen from fig. 13, the optical distortion is controlled to be within 2%, which means that the distortion of the optical lens 300 is well corrected. It can be seen from fig. 14 that the axial chromatic aberration of the shortest wavelength and the maximum wavelength is controlled within ±0.03 mm, which means that the axial chromatic aberration of the optical lens 300 is well corrected. As can be seen from fig. 15, the vertical chromatic aberration at different wavelengths is controlled within ±2.0 microns, indicating that the vertical chromatic aberration of the optical lens 300 is well corrected. As can be seen from fig. 12 to 15, the aberration of the optical lens 300 is well balanced, and has good optical imaging quality.

Referring to table 7, the optical characteristics of the optical lens provided in the above three embodiments, including the total optical length TTL, the effective focal length f, the field angle FOV, the image height IH, the f-number Fno, and the correlation values corresponding to each of the above conditional expressions, are shown.

TABLE 7

In summary, the optical lens provided by the invention has at least the following advantages:

(1) The optical lens provided by the invention adopts a seven-piece type compact structure, and adopts specific surface shape collocation and reasonable focal power distribution, so that the lens has a compact structure and smaller head outer diameter (the head outer diameter can be less than 4 mm), and also has an ultra-high pixel of 50M, thereby better realizing the balance of small volume and high pixel of the lens.

(2) The optical lens provided by the invention has a larger imaging surface through reasonable collocation of the focal power and the surface type of each lens, can be matched with a 1/1.31 inch large-size sensor chip, and meets the shooting configuration of the current mainstream.

(3) The optical lens provided by the invention has a larger aperture, and the control range of the light quantity is also larger, thereby being beneficial to shooting in dim light or dim environment; the depth of field range setting is also bigger, and the imaging picture has stronger depth feeling and spatial feeling.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means 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 present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above examples merely represent a few embodiments of the present invention, which are described in more detail and are not to be construed as limiting the scope of the present invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of the invention should be assessed as that of the appended claims.

Claims

1. An optical lens comprising seven lenses, wherein the lens comprises, in order from an object side to an imaging surface along an optical axis:

the first lens with positive focal power has a convex object side surface and a concave image side surface;

a second lens element with positive refractive power having a convex object-side surface and a concave image-side surface;

a third lens element with positive refractive power having a convex object-side surface at a paraxial region and a convex image-side surface;

a fourth lens having negative optical power;

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

a sixth lens element with negative refractive power having a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region;

a seventh lens element with negative refractive power having a concave object-side surface and a concave image-side surface at a paraxial region;

wherein, the optical lens satisfies the conditional expression: 1.7< IH/f <2.0, IH/FNo >6.5mm, f represents the effective focal length of the optical lens, IH represents the image height corresponding to the full field angle of the optical lens, and FNo represents the f-number of the optical lens.

2. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 1.5< f1/f <4, wherein f1 represents a focal length of the first lens.

3. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 0.4< f1/f2<3, where f1 represents the focal length of the first lens and f2 represents the focal length of the second lens.

4. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 0.3< f3/f <3, -8< f4/f < -1 >, wherein f3 represents the focal length of the third lens and f4 represents the focal length of the fourth lens.

5. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 0.9< f5/f <5, -0.8< f5/f6< -0.25, wherein f5 represents the focal length of the fifth lens and f6 represents the focal length of the sixth lens.

6. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: -2.3< f7/f < -1, wherein f7 represents the focal length of the seventh lens.

7. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 0.5< R1/R2<1,0.2< R2/f <1, wherein R1 represents a radius of curvature of an object side surface of the first lens, and R2 represents a radius of curvature of an image side surface of the first lens.

8. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 1< R11/R12<4,2< R11/f <5, wherein R11 represents a radius of curvature of an object side surface of the sixth lens, R12 represents a radius of curvature of an image side surface of the sixth lens, and f represents an effective focal length of the optical lens.

9. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 1< R12/R14<3, wherein R12 represents a radius of curvature of an image side surface of the sixth lens, and R14 represents a radius of curvature of an image side surface of the seventh lens.

10. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 1.1< TTL/f <1.38,0.6< TTL/IH <0.7, wherein TTL represents the total optical length of the optical lens.

11. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 0.26< DM1/IH <0.31, DM1 representing the maximum effective aperture of the first lens.