CN111367051A

CN111367051A - Optical imaging system, lens and electronic equipment

Info

Publication number: CN111367051A
Application number: CN202010302527.5A
Authority: CN
Inventors: 党绪文; 刘彬彬; 李明; 邹海荣
Original assignee: OFilm Tech Co Ltd
Current assignee: OFilm Group Co Ltd
Priority date: 2020-04-16
Filing date: 2020-04-16
Publication date: 2020-07-03

Abstract

The invention discloses an optical imaging system, a lens and an electronic device. An optical imaging system, comprising in order from an object side to an image side along an optical axis: the lens comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens; the optical imaging system satisfies the conditional expression: 0.5 < (| SAG51| + SAG52)/CT5 < 3.5; the SAG51 is a distance from an intersection point of an object side surface of the fifth lens and an optical axis to an edge of an optically effective area of the object side surface of the fifth lens projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface of the fifth lens and the optical axis to an edge of an optically effective area of the image side surface of the fifth lens projected on the optical axis, and the CT5 is a central thickness of the fifth lens on the optical axis. The invention can effectively reduce the incidence angle of the chief ray of the optical imaging system to the imaging surface, thereby being beneficial to reducing the sensitivity of the optical imaging system. The invention also discloses a lens with the optical imaging system and an electronic device with the lens.

Description

Optical imaging system, lens and electronic equipment

Technical Field

The present invention relates to the field of optical imaging, and in particular, to an optical imaging system, a lens barrel, and an electronic device.

Background

With the development of science and technology and the popularization of intelligent electronic equipment, equipment with the image taking function is widely favored by people. The trend of smart electronic devices to be more and more lightweight and ultra-thin requires that the lens in the smart electronic device should have a smaller weight and a lower cost.

A plurality of lenses are commonly used in a lens to realize optical imaging, however, the incident angle of the chief ray of the combination of the existing lenses to the image plane is large, so that the sensitivity of the optical imaging system is high.

Disclosure of Invention

In view of this, the present invention provides an optical imaging system, a lens barrel and an electronic device, in which the optical imaging system can effectively reduce the incident angle of the chief ray of the optical imaging system to the imaging plane, thereby being beneficial to reducing the sensitivity of the optical imaging system.

An optical imaging system comprising, in order from an object side to an image side along an optical axis:

the first lens element with positive refractive power has a convex object-side surface at a paraxial region;

a second lens element with refractive power; the first lens and the second lens are glued to form a glued lens;

the third lens element with refractive power has a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region;

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

a fifth lens element with refractive power; the object side surface and the image side surface of the fifth lens are both aspheric surfaces; at least one of the object side surface and the image side surface of the fifth lens is provided with at least one inflection point;

the optical imaging system satisfies the conditional expression:

0.5＜(|SAG51|+SAG52)/CT5＜3.5；

the SAG51 is a distance from an intersection point of an object side surface of the fifth lens and an optical axis to an edge of an optically effective area of the object side surface of the fifth lens projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface of the fifth lens and the optical axis to an edge of an optically effective area of the image side surface of the fifth lens projected on the optical axis, and the CT5 is a central thickness of the fifth lens on the optical axis. Therefore, the fifth lens meets the characteristic that 0.5 < (| SAG51| + SAG52)/CT5 < 3.5, the incident angle of the chief ray of the optical imaging system to the imaging surface is reduced, and the sensitivity of the optical imaging system is favorably reduced. Meanwhile, the fifth lens is prevented from being too thin or too thick due to the characteristics, and the incident angle of the chief ray in the optical imaging system to the imaging surface is favorably reduced, so that the sensitivity of the optical imaging system is favorably reduced.

In one embodiment, the optical imaging system satisfies the following conditional expression: 1.0mm^-1＜(n1+n2)/f≤1.3mm^-1；

Wherein n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, f is the effective focal length of the optical imaging system, and the reference wavelength of light is 587.6 nm. The refractive power distribution of the first lens and the second lens is proper, so that chromatic aberration and spherical aberration can be reduced to the maximum extent, and the imaging quality of the optical imaging system is improved.

In one embodiment, the optical imaging system satisfies the following conditional expression: f12/f is more than 0.8 and less than 1.7;

wherein f12 is an effective focal length of the first lens and the second lens after being cemented, and f is an effective focal length of the optical imaging system. The first lens and the second lens are cemented lenses, when the formula is satisfied, the focal power of the optical imaging system can be reasonably distributed, the introduction of primary spherical aberration and primary chromatic aberration is reduced, and the resolution power of the optical imaging system is effectively improved.

In one embodiment, the optical imaging system satisfies the following conditional expression: 1.4 < EPD/SD31 < 2.0;

where EPD is the entrance pupil diameter of the optical imaging system and SD31 is the maximum effective radius of the object side of the third lens. Satisfying the above formula, it is shown that the third lens and the first lens have similar optical apertures, so that the optical imaging system maintains a smaller volume, which is beneficial to the arrangement of the lenses and the compression of the size of the optical imaging system; meanwhile, the light angle deflection angle can be reduced by satisfying the above formula, and the sensitivity of the optical imaging system is reduced.

In one embodiment, the optical imaging system satisfies the following conditional expression: (| f2| + | f3|)/R31< 57.0;

wherein f2 is an effective focal length of the second lens, f3 is an effective focal length of the third lens, and R31 is a radius of curvature of an object-side surface of the third lens at the optical axis. Under the condition that the chromatic aberration of the cemented lens is reduced, the third lens is reasonably matched with the cemented lens to adjust the refractive power, so that the comprehensive spherical aberration, the chromatic aberration and the distortion of the front three lens groups are reduced to a proper degree, and the design difficulty of the fourth lens and the fifth lens is reduced. Meanwhile, when the curvature radius distribution of the third lens is proper, the lens surface type can be prevented from being too complicated, and the molding and manufacturing of the lens are facilitated.

In one embodiment, the optical imaging system satisfies the following conditional expression: f/| f3| < 0.70;

wherein f is an effective focal length of the optical imaging system, and f3 is an effective focal length of the third lens. The refractive power of the third lens is reasonably distributed, so that light rays are favorably diffused gradually, and the overlarge deflection angle of light ray deflection caused by the fourth lens and the fifth lens is avoided; meanwhile, when the above formula is satisfied, the aberration generated by the third lens can be sharply reduced, so that the imaging quality is improved, and the assembly sensitivity of the optical imaging system is reduced.

In one embodiment, the optical imaging system satisfies the following conditional expression: 6 < (f1+ | f2| + | f3|)/f < 46.0;

wherein f1 is an effective focal length of the first lens, f2 is an effective focal length of the second lens, f3 is an effective focal length of the third lens, and f is an effective focal length of the optical imaging system. The sizes and the refractive powers of the first lens, the second lens and the third lens are reasonably configured, so that the front lens group can be prevented from generating larger spherical aberration, and the integral resolving power of the optical imaging system can be improved; meanwhile, when the above formula is satisfied, the sizes of the first lens, the second lens, and the third lens can be reduced, which contributes to realizing a miniaturized optical imaging system.

In one embodiment, the optical imaging system satisfies the following conditional expression: i R41/R51I < 4.0;

wherein R41 is a radius of curvature of an object-side surface of the fourth lens element at the optical axis, and R51 is a radius of curvature of an object-side surface of the fifth lens element at the optical axis. The positive refractive power of the fourth lens element can increase the spherical aberration of the optical imaging system, and the refractive power perpendicular to the optical axis can be reasonably distributed by arranging a plurality of inflection points on the object side surface and/or the image side surface of the fifth lens element, so that the overall aberration of the optical lens can be reasonably controlled, and the size of the dispersed spot can be favorably reduced.

In one embodiment, the optical imaging system satisfies the following conditional expression: r41/f 4 is more than or equal to 1.2 and less than 2.9;

wherein R41 is a radius of curvature of an object-side surface of the fourth lens at the optical axis, f4 is an effective focal length of the fourth lens. The focal power and the curvature radius of the fourth lens are reasonably set, so that the surface type complexity of the fourth lens can be reduced, and the increase of field curvature and distortion in the meridian direction is restrained to a certain extent; the reduction of the surface complexity of the fourth lens is also beneficial to reducing the molding difficulty of the lens and improving the integral image quality of the optical imaging system.

In one embodiment, the optical imaging system satisfies the following conditional expression: 3.0< TTL < 4.0;

the image side of the optical imaging system is provided with an imaging surface, and TTL is the distance from the object side surface of the first lens to the imaging surface of the optical imaging system. The TTL is controlled, namely the total optical length of the optical imaging system is controlled, when the TTL is lower, the total optical length of the optical imaging system is reduced, the size of the optical imaging system is correspondingly reduced, and the optical imaging system tends to be lighter, thinner and smaller.

In one embodiment, the optical imaging system satisfies the following conditional expression: n1 > 1.535;

wherein n1 is the refractive index of the first lens, and the reference wavelength of light is 587.6 nm. The first lens introduces light into the optical imaging system, and the refractive index of the first lens influences the deflection angle of the light passing through the first lens, and the deflection angle further influences the guiding condition of other lenses to the light. The high-refractive-index material can reduce the deflection angle of the first lens, and is beneficial to guiding light rays by the rear lens, so that the image quality of the whole optical imaging system is influenced.

In one embodiment, the optical imaging system satisfies the following conditional expression: FOV is more than or equal to 70 degrees and less than or equal to 85 degrees;

wherein the FOV is a maximum field angle of the optical imaging system. The maximum field angle of the optical imaging system is controlled in a reasonable range, so that the optical imaging system has better aberration balancing capability, and the distortion of the optical imaging system can be controlled.

A lens comprises a photosensitive element and the optical imaging system, wherein the photosensitive element is arranged on the image side of the optical imaging system. The lens can reduce the incidence angle of the chief ray of the optical imaging system to the imaging surface, and is favorable for reducing the sensitivity of the optical imaging system. Meanwhile, the fifth lens is prevented from being too thin or too thick due to the characteristics, and the incident angle of the chief ray in the optical imaging system to the imaging surface is favorably reduced, so that the sensitivity of the optical imaging system is favorably reduced.

An electronic device comprises a body and the lens, wherein the lens is arranged on the body. The electronic equipment can reduce the incidence angle of the chief ray of the optical imaging system to the imaging surface, and is further beneficial to reducing the sensitivity of the optical imaging system. Meanwhile, the fifth lens is prevented from being too thin or too thick due to the characteristics, and the incident angle of the chief ray in the optical imaging system to the imaging surface is favorably reduced, so that the sensitivity of the optical imaging system is favorably reduced.

In summary, the fifth lens element satisfies the characteristic of 0.5 < (| SAG51| + SAG52)/CT5 < 3.5, so as to reduce the incident angle of the chief ray of the optical imaging system to the imaging surface, thereby being beneficial to reducing the sensitivity of the optical imaging system. Meanwhile, the fifth lens is prevented from being too thin or too thick due to the characteristics, and the incident angle of the chief ray in the optical imaging system to the imaging surface is favorably reduced, so that the sensitivity of the optical imaging system is favorably reduced.

Drawings

To more clearly illustrate the structural features and effects of the present invention, a detailed description is given below with reference to the accompanying drawings and specific embodiments.

Fig. 1 is a schematic configuration diagram of an optical imaging system of embodiment 1 of the present invention;

fig. 2A to 2C show a spherical aberration curve, an astigmatism curve, and a distortion curve, respectively, of the optical imaging system of embodiment 1;

fig. 3 is a schematic structural view of an optical imaging system of embodiment 2 of the present invention;

fig. 4A to 4C show a spherical aberration curve, an astigmatism curve, and a distortion curve, respectively, of the optical imaging system of embodiment 2;

fig. 5 is a schematic structural view of an optical imaging system of embodiment 3 of the present invention;

fig. 6A to 6C show a spherical aberration curve, an astigmatism curve, and a distortion curve, respectively, of the optical imaging system of embodiment 3;

FIG. 7 is a schematic structural view of an optical imaging system according to embodiment 4 of the present invention;

fig. 8A to 8C show a spherical aberration curve, an astigmatism curve, and a distortion curve, respectively, of the optical imaging system of embodiment 4;

FIG. 9 is a schematic structural view of an optical imaging system according to embodiment 5 of the present invention;

fig. 10A to 10C show a spherical aberration curve, an astigmatism curve, and a distortion curve, respectively, of the optical imaging system of example 5;

fig. 11 is a schematic structural view of an optical imaging system of embodiment 6 of the present invention;

fig. 12A to 12C show a spherical aberration curve, an astigmatism curve, and a distortion curve, respectively, of the optical imaging system of example 6;

fig. 13 is a schematic structural view of an optical imaging system of embodiment 7 of the present invention;

fig. 14A to 14C show a spherical aberration curve, an astigmatism curve, and a distortion curve, respectively, of the optical imaging system of example 7.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.

The application provides an optical imaging system, which is beneficial to reducing the incidence angle of a chief ray of the optical imaging system to an imaging surface, and further beneficial to reducing the sensitivity of the optical imaging system.

The optical imaging system is introduced as follows:

an optical imaging system comprises an object side and an image side, wherein the image side is provided with an imaging surface. The optical imaging system includes, in order from an object side to an image side along an optical axis:

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

the optical imaging system satisfies the conditional expression:

0.5＜(|SAG51|+SAG52)/CT5＜3.5；

the SAG51 is a distance from an intersection point of an object side surface of the fifth lens and an optical axis to an edge of an optically effective area of the object side surface of the fifth lens projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface of the fifth lens and the optical axis to an edge of an optically effective area of the image side surface of the fifth lens projected on the optical axis, and the CT5 is a central thickness of the fifth lens on the optical axis.

The fifth lens meets the characteristic that 0.5 < (| SAG51| + SAG52)/CT5 is less than 3.5, the incident angle of the chief ray of the optical imaging system to the imaging surface is reduced, and the sensitivity of the optical imaging system is favorably reduced. Meanwhile, the fifth lens is prevented from being too thin or too thick due to the characteristics, and the incident angle of the chief ray in the optical imaging system to the imaging surface is favorably reduced, so that the sensitivity of the optical imaging system is favorably reduced.

In an exemplary embodiment, (| SAG51| + SAG52)/CT5 may be 0.6, 3.4, 0.55, 3.45, 0.7, 3.3, etc., and may be other values satisfying the conditional expression of 0.5 < (| SAG51| + SAG52)/CT5 < 3.5.

In an exemplary embodiment, at least one of the object-side surface and the image-side surface of the fifth lens element has at least one inflection point, which is favorable for correcting distortion and curvature of field generated by the optical imaging system when the fifth lens element has a plurality of inflection points, so that the refractive power configuration of the imaging surface close to the optical imaging system is more uniform.

In this application, the first lens includes an object side surface close to the object side and an image side surface close to the image side, the second lens includes an object side surface close to the object side and an image side surface close to the image side, the third lens includes an object side surface close to the object side and an image side surface close to the image side, and the fourth lens includes an object side surface close to the object side and an image side surface close to the image side. In the optical imaging system, a first lens and a second lens are cemented to form a cemented lens; the third lens, the fourth lens and the fifth lens may be independent of and have an air space between adjacent lenses. By introducing the cemented lens, the cemented lens is beneficial to eliminating self chromatic aberration of each lens in the cemented lens group, and partial chromatic aberration can be remained to balance chromatic aberration of the optical imaging system, so that the chromatic aberration balancing capability of the optical imaging system can be enhanced, and the imaging resolution is improved. And the air space between the two lenses is omitted by the gluing of the lenses, so that the whole structure of the optical imaging system is compact and simple, the optical total length of the optical imaging system is favorably shortened, and the requirement of miniaturization is met. In addition, the gluing of the lenses can reduce the tolerance sensitivity of the lenses such as tilt/decentration generated in the assembling process, and the coaxiality in the assembling process is better than that of a separated lens, so that the yield of the assembling process is improved.

In an exemplary embodiment, the first lens element may have positive refractive power, and the object-side surface of the first lens element is convex; the second lens element can have refractive power; the third lens element with refractive power has a convex object-side surface and a concave image-side surface; the fourth lens element with positive refractive power has a concave object-side surface at a paraxial region, and has a convex image-side surface at the paraxial region; in an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: 1.0mm^-1＜(n1+n2)/f≤1.3mm^-1(ii) a Wherein n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, f is the effective focal length of the optical imaging system, and the reference wavelength of light is 587.6 nm. The refractive power distribution of the first lens and the second lens is proper, so that chromatic aberration and spherical aberration can be reduced to the maximum extent, and the imaging quality of the optical imaging system is improved.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: f12/f is more than 0.8 and less than 1.7; wherein f12 is the effective focal length after the first lens and the second lens are cemented, and f is the effective focal length of the optical imaging system. The first lens and the second lens are cemented lenses, when the formula is satisfied, the focal power of the optical imaging system can be reasonably distributed, the introduction of primary spherical aberration and primary chromatic aberration is reduced, and the resolution power of the optical imaging system is effectively improved.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: 1.4 < EPD/SD31 < 2.0; where EPD is the entrance pupil diameter of the optical imaging system, SD31 is the maximum effective radius of the object side of the third lens, which may be the maximum effective radius of the object side of the third lens. Satisfying the above formula, it is shown that the third lens and the first lens have similar optical apertures, so that the optical imaging system maintains a smaller volume, which is beneficial to the arrangement of the lenses and the compression of the size of the optical imaging system; meanwhile, the light angle deflection angle can be reduced by satisfying the above formula, and the sensitivity of the optical imaging system is reduced.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: (| f2| + | f3|)/R31< 57.0; where f2 is the effective focal length of the second lens, f3 is the effective focal length of the third lens, and R31 is the radius of curvature at the paraxial region of the object-side surface of the third lens. Under the condition that the chromatic aberration of the cemented lens is reduced, the third lens is reasonably matched with the cemented lens to adjust the refractive power, so that the comprehensive spherical aberration, the chromatic aberration and the distortion of the front three lens groups are reduced to a proper degree, and the design difficulty of the fourth lens and the fifth lens is reduced. Meanwhile, when the curvature radius distribution of the third lens is proper, the lens surface type can be prevented from being too complicated, and the molding and manufacturing of the lens are facilitated.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: f/| f3| < 0.70; where f is the effective focal length of the optical imaging system, and f3 is the effective focal length of the third lens. The refractive power of the third lens is reasonably distributed, so that light rays are favorably diffused gradually, and the overlarge deflection angle of light ray deflection caused by the fourth lens and the fifth lens is avoided; meanwhile, when the above formula is satisfied, the aberration generated by the third lens can be sharply reduced, so that the imaging quality is improved, and the assembly sensitivity of the optical imaging system is reduced.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: 6 < (f1+ | f2| + | f3|)/f < 46.0; wherein f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, f3 is the effective focal length of the third lens, and f is the effective focal length of the optical imaging system. The sizes and the refractive powers of the first lens, the second lens and the third lens are reasonably configured, so that the front lens group can be prevented from generating larger spherical aberration, and the integral resolving power of the optical imaging system can be improved; meanwhile, when the above formula is satisfied, the sizes of the first lens, the second lens, and the third lens can be reduced, which contributes to realizing a miniaturized optical imaging system.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: i R41/R51I < 4.0; wherein R41 is a radius of curvature at the paraxial region of the object side surface of the fourth lens, and R51 is a radius of curvature at the paraxial region of the object side surface of the fifth lens. The positive refractive power of the fourth lens element can increase the spherical aberration of the optical imaging system, and the refractive power perpendicular to the optical axis can be reasonably distributed by arranging a plurality of inflection points on the object side surface and/or the image side surface of the fifth lens element, so that the overall aberration of the optical lens can be reasonably controlled, and the size of the dispersed spot can be favorably reduced.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: r41/f 4 is more than or equal to 1.2 and less than 2.9;

where R41 is the radius of curvature at the paraxial region of the object side of the fourth lens, and f4 is the effective focal length of the fourth lens. The focal power and the curvature radius of the fourth lens are reasonably set, so that the surface type complexity of the fourth lens can be reduced, and the increase of field curvature and distortion in the meridian direction is restrained to a certain extent; the reduction of the surface complexity of the fourth lens is also beneficial to reducing the molding difficulty of the lens and improving the integral image quality of the optical imaging system.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: 3.0< TTL < 4.0;

wherein, TTL is a distance from an object-side surface of the first lens element to an imaging surface of the optical imaging system, i.e., an optical total length. The TTL is controlled, namely the total optical length of the optical imaging system is controlled, when the TTL is lower, the total optical length of the optical imaging system is reduced, the size of the optical imaging system is correspondingly reduced, and the optical imaging system tends to be lighter, thinner and smaller.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: n1 > 1.535; wherein n1 is the refractive index of the first lens, and the reference wavelength of light is 587.6 nm. The first lens introduces light into the optical imaging system, and the refractive index of the first lens influences the deflection angle of the light passing through the first lens, and the deflection angle further influences the guiding condition of other lenses to the light. The high-refractive-index material can reduce the deflection angle of the first lens, and is beneficial to guiding light rays by the rear lens, so that the image quality of the whole optical imaging system is influenced.

In an exemplary embodiment, the optical imaging system may satisfy the following conditional expression: FOV is more than or equal to 70 degrees and less than or equal to 85 degrees; where the FOV is the maximum field angle of the optical imaging system, optionally the field angle is the field angle of 1.0 field of view, i.e. the maximum field angle. The maximum field angle of the optical imaging system is controlled in a reasonable range, so that the optical imaging system has better aberration balancing capability, and the distortion of the optical imaging system can be controlled.

In the embodiment of the present application, at least one of the mirror surfaces of each lens is an aspherical mirror surface; that is, at least one of the object-side surface and the image-side surface of each of the first lens, the second lens, the third lens, the fourth lens, and the fifth lens is an aspherical mirror surface. The aspheric lens is characterized in that: the curvature varies continuously from the center of the lens to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has better curvature radius characteristics, and has advantages of improving distortion aberration and improving astigmatic aberration. After the aspheric lens is adopted, the aberration generated during imaging can be eliminated as much as possible, thereby improving the imaging quality. Preferably, each of the first lens element, the second lens element, the third lens element, the fourth lens element, and the fifth lens element has an object-side surface and an image-side surface which are aspheric mirror surfaces.

In the embodiments of the present application, the first lens, the second lens, the third lens, the fourth lens, and the fifth lens are all made of plastic. The plastic lens is easy to manufacture, high in forming efficiency and low in cost, large-scale mass production is facilitated, the advantages of easiness in manufacturing the plastic lens, chromatic aberration removal of the cemented lens and good coaxiality are combined, and the yield of the assembling process can be greatly improved.

In an exemplary embodiment, the optical imaging system may further include at least one diaphragm to improve the imaging quality of the optical imaging system. Preferably, the diaphragm may be disposed between the object side and the first lens.

The invention also provides a lens, which comprises a photosensitive element and the optical imaging system, wherein the photosensitive element is arranged at the image side of the optical imaging system; the photosensitive element may be a Charge Coupled Device (CCD) or a Complementary Metal Oxide Semiconductor (CMOS). The lens can achieve the best imaging effect through the design of an optical imaging system. Further, the lens may further include a lens barrel, a supporting device, or a combination thereof.

The invention also provides electronic equipment, which comprises a body and the lens, wherein the lens is arranged on the body of the electronic equipment, and the electronic equipment has a lens with an excellent imaging effect. The electronic device may be a portable device such as a smartphone, a digital camera, a tablet computer, and a wearable device.

Specific examples of an optical imaging lens applicable to the above-described embodiments are further described below with reference to the drawings.

Example 1

An optical imaging system according to embodiment 1 of the present application is described below with reference to fig. 1 to 2C. Fig. 1 shows a schematic structural diagram of an optical imaging system according to embodiment 1 of the present application.

As illustrated in fig. 1, an optical imaging system according to an exemplary embodiment of the present application includes, once from an object side to an image side: a stop ST0, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6, and an image forming surface S13.

The first lens element E1 with positive refractive power has a convex object-side surface S1 and a concave image-side surface S2 at a paraxial region; at the circumference, the object-side surface S1 of the first lens element is convex, and the image-side surface S2 is concave. The second lens element E2 with negative refractive power has a convex object-side surface S3 and a concave image-side surface S4 at a paraxial region; at the circumference, the object-side surface S3 of the second lens element is convex, and the image-side surface S4 is convex. The third lens element E3 with negative refractive power has a convex object-side surface S5 and a concave image-side surface S6 at a paraxial region; at the circumference, the object-side surface S5 of the third lens element is convex, and the image-side surface S6 is concave. The fourth lens element E4 with positive refractive power has a concave object-side surface S7 and a convex image-side surface S8 at a paraxial region; at the circumference, the object-side surface S7 of the fourth lens element is convex, and the image-side surface S8 is concave. The fifth lens element E5 with negative refractive power has a convex object-side surface S9 and a concave image-side surface S10 at a paraxial region; at the circumference, the object-side surface S9 of the fifth lens element is concave, and the image-side surface S10 is convex. Filter E6 has an object side S11 and an image side S12. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.

In the present embodiment, the image-side surface S2 of the first lens E1 is cemented with the object-side surface S3 of the second lens E2 to form a cemented lens; any one of the third lens E3, the fourth lens E4, and the fifth lens E5 is independent of and has an air space with its neighboring lens.

Table 1 shows the surface type, radius of curvature, thickness, material, refractive index, abbe number, and effective focal length of each lens of the optical imaging system of example 1, where the unit of the radius of curvature, thickness, and effective focal length are all millimeters (mm).

TABLE 1

The effective focal length of the optical imaging system in example 1 was EFL, and the aperture value of the optical imaging system was F_noThe field angle of the optical imaging system is FOV, the total optical length of the optical imaging system is TTL, and the numerical values are: f2.44 mm, F_NO2.09 FOV 84.98 (degrees) and TTL 3.60 mm.

As can be seen from table 1, the object-side surface and the image-side surface of any one of the first lens element E1 through the fifth lens element E5 are aspheric. In the present embodiment, the profile x of each aspheric lens can be defined using, but not limited to, the following aspheric formula:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/R (i.e., paraxial curvature c is the inverse of radius of curvature R in table 1 above); k is a conic coefficient; ai is the correction coefficient of the i-th order of the aspherical surface. Table 2 below gives the conic coefficients k and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirrors S1-S10 in example 1.

TABLE 2

The optical imaging system in embodiment 1 satisfies the following relationship:

(| SAG51| + SAG52)/CT5 ═ 1.19; the SAG51 is a distance from an intersection point of an object side surface S9 of the fifth lens E5 and an optical axis to an edge of an optically effective area of an object side surface S9 of the fifth lens E5 projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface S10 of the fifth lens E5 and the optical axis to an edge of an optically effective area of an image side surface S10 of the fifth lens E5 projected on the optical axis, and the CT5 is a central thickness of the fifth lens E5 on the optical axis.

(n1+n2)/f＝1.30mm^-1Wherein n1 is the refractive index of the first lens E1, n2 is the refractive index of the second lens E2, and f is the total effective focal length of the optical imaging system;

f12/f is 1.41, f12 is the effective focal length of the first lens and the second lens after being cemented, and f is the effective focal length of the optical imaging system. Alternatively, f12 is 3.45mm and f is 2.45 mm.

EPD/SD31 ═ 1.51, where EPD is the entrance pupil diameter of the optical imaging system, SD31 is the maximum effective radius of the object side S5 of the third lens E3;

(| f2| + | f3|)/R31 ═ 11.18, where f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and R31 is the radius of curvature at the paraxial position of the object-side surface S5 of the third lens E3;

f/| f3|, where f is the total effective focal length of the optical imaging system, and f3 is the effective focal length of the third lens E3;

(f1+ | f2| + | f3|)/f ═ 14.69, where f1 is the effective focal length of the first lens E1, f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and f is the total effective focal length of the optical imaging system;

i R41/R51| ═ 3.62, where R41 is the radius of curvature at the paraxial region of the object-side surface S7 of the fourth lens E4, and R51 is the radius of curvature at the paraxial region of the object-side surface S9 of the fifth lens E5.

L R41 l/f 4 ═ 2.85, where R41 is the radius of curvature at the paraxial region of the object-side S7 of the fourth lens E4, and f4 is the effective focal length of the fourth lens E4;

TTL is 3.60mm, where TTL is a distance from the object-side surface S1 of the first lens element E1 to the imaging surface S13 of the optical imaging system;

n1 is 1.651, wherein n1 is the refractive index of the first lens E1, and the reference wavelength of light is 587.6 nm.

The FOV is 84.98 °, where FOV is the maximum field angle of the optical imaging system.

Fig. 2A shows a spherical aberration curve of the optical imaging system of embodiment 1, which represents the deviation of the convergent focus of light rays of different wavelengths after passing through the lens. Fig. 2B shows astigmatism curves of the optical imaging system of example 1, which represent meridional field curvature and sagittal field curvature. Fig. 2C shows a distortion curve of the optical imaging system of embodiment 1, which represents distortion magnitude values corresponding to different image heights. As can be seen from fig. 2A to 2C, the optical imaging system according to embodiment 1 can achieve good imaging quality.

Example 2

An optical imaging system according to embodiment 2 of the present application is described below with reference to fig. 3 to 4C. In this embodiment and the following embodiments, descriptions of parts similar to those of embodiment 1 will be omitted for the sake of brevity. Fig. 3 shows a schematic structural diagram of an optical imaging system according to embodiment 2 of the present application.

As illustrated in fig. 3, an optical imaging system according to an exemplary embodiment of the present application includes, once from an object side to an image side: a stop ST0, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6, and an image forming surface S13.

The first lens element E1 with positive refractive power has a convex object-side surface S1 and a convex image-side surface S2 at a paraxial region; at the circumference, the object-side surface S1 of the first lens element is convex, and the image-side surface S2 is convex. The second lens element E2 with negative refractive power has a concave object-side surface S3 and a concave image-side surface S4 at a paraxial region; at the circumference, the object-side surface S3 of the second lens element is convex, and the image-side surface S4 is concave. The third lens element E3 with negative refractive power has a convex object-side surface S5 and a concave image-side surface S6 at a paraxial region; at the circumference, the object-side surface S5 of the third lens element is concave, and the image-side surface S6 is concave. The fourth lens element E4 with positive refractive power has a concave object-side surface S7 and a convex image-side surface S8 at a paraxial region; at the circumference, the object-side surface S7 of the fourth lens element is concave, and the image-side surface S8 is convex. The fifth lens element E5 with negative refractive power has a concave object-side surface S9 and a concave image-side surface S10 at a paraxial region; at the circumference, the object-side surface S9 of the fifth lens element is convex, and the image-side surface S10 is convex. Filter E6 has an object side S11 and an image side S12. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.

Table 3 shows the surface type, radius of curvature, thickness, material, refractive index, abbe number, and effective focal length of each lens of the optical imaging system of example 2, where the unit of the radius of curvature, thickness, and effective focal length are all millimeters (mm).

TABLE 3

The effective focal length of the optical imaging system in example 2 was EFL, and the aperture value of the optical imaging system was F_noThe field angle of the optical imaging system is FOV, the total optical length of the optical imaging system is TTL, and the numerical values are: f3.01 mm, F_NO2.15, FOV 72.63 (degrees), TTL 3.96 mm.

As can be seen from table 3, the object-side surface and the image-side surface of any one of the first lens element E1 through the fifth lens element E5 are aspheric. Table 4 below gives the conic coefficients k and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirrors S1-S10 in example 2.

TABLE 4

The optical imaging system in embodiment 2 satisfies the following relationship:

(| SAG51| + SAG52)/CT5 ═ 0.83; the SAG51 is a distance from an intersection point of an object side surface S9 of the fifth lens E5 and an optical axis to an edge of an optically effective area of an object side surface S9 of the fifth lens E5 projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface S10 of the fifth lens E5 and the optical axis to an edge of an optically effective area of an image side surface S10 of the fifth lens E5 projected on the optical axis, and the CT5 is a central thickness of the fifth lens E5 on the optical axis.

(n1+n2)/f＝1.06mm^-1Wherein n1 is the refractive index of the first lens E1, n2 is the refractive index of the second lens E2, and f is the total effective focal length of the optical imaging system;

f12/f is 1.10, f12 is the effective focal length of the first lens and the second lens after being cemented, and f is the effective focal length of the optical imaging system. Alternatively, f12 is 3.32mm and f is 3.01 mm.

EPD/SD31 ═ 1.82, where EPD is the entrance pupil diameter of the optical imaging system, SD31 is the maximum effective radius of the object side S5 of the third lens E3;

(| f2| + | f3|)/R31 ═ 13.27, where f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and R31 is the radius of curvature at the paraxial position of the object-side surface S5 of the third lens E3;

(f1+ | f2| + | f3|)/f 12.88, wherein f1 is the effective focal length of the first lens E1, f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and f is the total effective focal length of the optical imaging system;

l R41/R51| -1.14, where R41 is the radius of curvature at the paraxial region of the object-side surface S7 of the fourth lens E4, and R51 is the radius of curvature at the paraxial region of the object-side surface S9 of the fifth lens E5.

L R41 l/f 4 ═ 2.19, where R41 is the radius of curvature at the paraxial region of the object-side S7 of the fourth lens E4, and f4 is the effective focal length of the fourth lens E4;

TTL is 3.96mm, where TTL is a distance from the object-side surface S1 of the first lens element E1 to the imaging surface S13 of the optical imaging system;

n1 is 1.545, wherein n1 is the refractive index of the first lens E1, and the reference wavelength of light is 587.6 nm.

And 72.63 degrees, wherein the FOV is the maximum field angle of the optical imaging system.

Fig. 4A shows a spherical aberration curve of the optical imaging system of embodiment 2, which represents the deviation of the convergent focus of light rays of different wavelengths after passing through the lens. Fig. 4B shows astigmatism curves of the optical imaging system of embodiment 2, which represent meridional field curvature and sagittal field curvature. Fig. 4C shows a distortion curve of the optical imaging system of embodiment 2, which represents distortion magnitude values corresponding to different image heights. As can be seen from fig. 4A to 4C, the optical imaging system according to embodiment 2 can achieve good imaging quality.

Example 3

An optical imaging system according to embodiment 3 of the present application is described below with reference to fig. 5 to 6C. Fig. 5 shows a schematic structural diagram of an optical imaging system according to embodiment 3 of the present application.

As illustrated in fig. 5, the optical imaging system according to the exemplary embodiment of the present application includes, once from an object side to an image side: a stop ST0, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6, and an image forming surface S13.

The first lens element E1 with positive refractive power has a convex object-side surface S1 and a convex image-side surface S2 at a paraxial region; at the circumference, the object-side surface S1 of the first lens element is convex, and the image-side surface S2 is convex. The second lens element E2 with positive refractive power has a concave object-side surface S3 and a convex image-side surface S4 at a paraxial region; at the circumference, the object-side surface S3 of the second lens element is concave, and the image-side surface S4 is convex. The third lens element E3 with negative refractive power has a convex object-side surface S5 and a concave image-side surface S6 at a paraxial region; at the circumference, the object-side surface S5 of the third lens element is concave, and the image-side surface S6 is concave. The fourth lens element E4 with positive refractive power has a concave object-side surface S7 and a convex image-side surface S8 at a paraxial region; at the circumference, the object-side surface S7 of the fourth lens element is concave, and the image-side surface S8 is convex. The fifth lens element E5 with negative refractive power has a convex object-side surface S9 and a concave image-side surface S10 at a paraxial region; at the circumference, the object-side surface S9 of the fifth lens element is convex, and the image-side surface S10 is convex. Filter E6 has an object side S11 and an image side S12. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.

Table 5 shows the surface type, radius of curvature, thickness, material, refractive index, abbe number, and effective focal length of each lens of the optical imaging system of example 3, wherein the unit of the radius of curvature, thickness, and effective focal length is millimeters (mm).

TABLE 5

The effective focal length of the optical imaging system in example 3 was EFL, and the aperture value of the optical imaging system was F_noThe field angle of the optical imaging system is FOV, the total optical length of the optical imaging system is TTL, and the numerical values are: f2.78 mm, F_NO2.00, FOV 78.3 (degrees), TTL 3.86 mm.

As can be seen from table 5, the object-side surface and the image-side surface of any one of the first lens element E1 through the fifth lens element E5 are aspheric. Table 6 below gives the cone coefficients k and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 which can be used for each of the aspherical mirrors S1-S10 in example 3.

TABLE 6

The optical imaging system in embodiment 3 satisfies the following relationship:

(| SAG51| + SAG52)/CT5 ═ 0.52; the SAG51 is a distance from an intersection point of an object side surface S9 of the fifth lens E5 and an optical axis to an edge of an optically effective area of an object side surface S9 of the fifth lens E5 projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface S10 of the fifth lens E5 and the optical axis to an edge of an optically effective area of an image side surface S10 of the fifth lens E5 projected on the optical axis, and the CT5 is a central thickness of the fifth lens E5 on the optical axis.

(n1+n2)/f＝1.15mm^-1Wherein n1 is the refractive index of the first lens E1, n2 is the refractive index of the second lens E2, and f is the total effective focal length of the optical imaging system;

f12/f is 0.89, f12 is the effective focal length of the first lens and the second lens after being cemented, and f is the effective focal length of the optical imaging system. Alternatively, f12 is 2.45mm and f is 2.74 mm.

EPD/SD31 ═ 1.67, where EPD is the entrance pupil diameter of the optical imaging system, SD31 is the maximum effective radius of the object side S5 of the third lens E3;

(| f2| + | f3|)/R31 ═ 0.25, where f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and R31 is the radius of curvature at the paraxial position of the object-side surface S5 of the third lens E3;

(f1+ | f2| + | f3|)/f ═ 6.35, where f1 is the effective focal length of the first lens E1, f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and f is the total effective focal length of the optical imaging system;

l R41/R51| ═ 0.48, where R41 is the radius of curvature at the paraxial region of the object-side surface S7 of the fourth lens E4, and R51 is the radius of curvature at the paraxial region of the object-side surface S9 of the fifth lens E5.

L R41/f 4 is 1.31, where R41 is the radius of curvature at the paraxial region of the object-side surface S7 of the fourth lens E4, and f4 is the effective focal length of the fourth lens E4;

TTL is 3.86mm, where TTL is a distance from the object-side surface S1 of the first lens element E1 to the imaging surface S13 of the optical imaging system;

The FOV is 78.3 °, where FOV is the maximum field angle of the optical imaging system.

Fig. 6A shows a spherical aberration curve of the optical imaging system of embodiment 3, which represents the deviation of the convergent focus of light rays of different wavelengths after passing through the lens. Fig. 6B shows astigmatism curves of the optical imaging system of example 3, which represent meridional field curvature and sagittal field curvature. Fig. 6C shows a distortion curve of the optical imaging system of embodiment 3, which represents distortion magnitude values corresponding to different image heights. As can be seen from fig. 6A to 6C, the optical imaging system according to embodiment 3 can achieve good imaging quality.

Example 4

An optical imaging system according to embodiment 4 of the present application is described below with reference to fig. 7 to 8C. Fig. 7 shows a schematic configuration diagram of an optical imaging system according to embodiment 3 of the present application.

As illustrated in fig. 7, the optical imaging system according to the exemplary embodiment of the present application includes, once from an object side to an image side: a stop ST0, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6, and an image forming surface S13.

The first lens element E1 with positive refractive power has a convex object-side surface S1 and a concave image-side surface S2 at a paraxial region; at the circumference, the object-side surface S1 of the first lens element is convex, and the image-side surface S2 is concave. The second lens element E2 with negative refractive power has a convex object-side surface S3 and a concave image-side surface S4 at a paraxial region; at the circumference, the object-side surface S3 of the second lens element is convex, and the image-side surface S4 is convex. The third lens element E3 with positive refractive power has a convex object-side surface S5 and a concave image-side surface S6 at a paraxial region; at the circumference, the object-side surface S5 of the third lens element is convex, and the image-side surface S6 is concave. The fourth lens element E4 with positive refractive power has a concave object-side surface S7 and a convex image-side surface S8 at a paraxial region; at the circumference, the object-side surface S7 of the fourth lens element is concave, and the image-side surface S8 is convex. The fifth lens element E5 with negative refractive power has a concave object-side surface S9 and a concave image-side surface S10 at a paraxial region; at the circumference, the object-side surface S9 of the fifth lens element is concave, and the image-side surface S10 is convex. Filter E6 has an object side S11 and an image side S12. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.

Table 7 shows the surface type, radius of curvature, thickness, material, refractive index, abbe number, and effective focal length of each lens of the optical imaging system of example 4, where the unit of the radius of curvature, thickness, and effective focal length are all millimeters (mm).

TABLE 7

The effective focal length of the optical imaging system in example 4 was EFL, and the aperture value of the optical imaging system was F_noThe field angle of the optical imaging system is FOV, the total optical length of the optical imaging system is TTL, and the numerical values are: f2.76 mm, F_NO1.78, FOV 76.91 (degrees), TTL 3.60 mm.

As can be seen from table 7, the object-side surface and the image-side surface of any one of the first lens element E1 through the fifth lens element E5 are aspheric. Table 8 below gives the conic coefficients k and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirrors S1-S10 in example 4.

TABLE 8

The optical imaging system in embodiment 4 satisfies the following relationship:

(| SAG51| + SAG52)/CT5 ═ 1.76; the SAG51 is a distance from an intersection point of an object side surface S9 of the fifth lens E5 and an optical axis to an edge of an optically effective area of an object side surface S9 of the fifth lens E5 projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface S10 of the fifth lens E5 and the optical axis to an edge of an optically effective area of an image side surface S10 of the fifth lens E5 projected on the optical axis, and the CT5 is a central thickness of the fifth lens E5 on the optical axis.

(n1+n2)/f＝1.12mm^-1Wherein n1 is the refractive index of the first lens E1, n2 is the refractive index of the second lens E2, and f is the total effective focal length of the optical imaging system;

f12/f is 1.23, f12 is the effective focal length of the first lens and the second lens after being cemented, and f is the effective focal length of the optical imaging system. Alternatively, f12 is 3.54mm and f is 2.87 mm.

EPD/SD31 ═ 1.94, where EPD is the entrance pupil diameter of the optical imaging system, SD31 is the maximum effective radius of the object side S5 of the third lens E3;

(| f2| + | f3|)/R31 ═ 56.13, where f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and R31 is the radius of curvature at the paraxial position of the object-side surface S5 of the third lens E3;

(f1+ | f2| + | f3|)/f 45.55, wherein f1 is the effective focal length of the first lens E1, f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and f is the total effective focal length of the optical imaging system;

l R41/R51| ═ 0.25, where R41 is the radius of curvature at the paraxial region of the object-side surface S7 of the fourth lens E4, and R51 is the radius of curvature at the paraxial region of the object-side surface S9 of the fifth lens E5.

L R41 l/f 4 ═ 2.05, where R41 is the radius of curvature at the paraxial region of the object-side S7 of the fourth lens E4, and f4 is the effective focal length of the fourth lens E4;

n1 is 1.535, where n1 is the refractive index of the first lens E1, and the reference wavelength of light is 587.6 nm.

And 76.91 degrees, wherein the FOV is the maximum field angle of the optical imaging system.

Fig. 8A shows a spherical aberration curve of the optical imaging system of example 4, which represents the deviation of the convergent focus of light rays of different wavelengths after passing through the lens. Fig. 8B shows astigmatism curves of the optical imaging system of example 4, which represent meridional field curvature and sagittal field curvature. Fig. 8C shows a distortion curve of the optical imaging system of embodiment 4, which represents distortion magnitude values corresponding to different image heights. As can be seen from fig. 8A to 8C, the optical imaging system according to embodiment 4 can achieve good imaging quality.

Example 5

An optical imaging system according to embodiment 5 of the present application is described below with reference to fig. 9 to 10C. Fig. 9 shows a schematic structural view of an optical imaging system according to embodiment 5 of the present application.

As illustrated in fig. 9, the optical imaging system according to the exemplary embodiment of the present application includes, once from an object side to an image side: a stop ST0, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6, and an image forming surface S13.

The first lens element E1 with positive refractive power has a convex object-side surface S1 and a concave image-side surface S2 at a paraxial region; at the circumference, the object-side surface S1 of the first lens element is convex, and the image-side surface S2 is concave. The second lens element E2 with negative refractive power has a convex object-side surface S3 and a concave image-side surface S4 at a paraxial region; at the circumference, the object-side surface S3 of the second lens element is convex, and the image-side surface S4 is convex. The third lens element E3 with positive refractive power has a convex object-side surface S5 and a concave image-side surface S6 at a paraxial region; at the circumference, the object-side surface S5 of the third lens element is concave, and the image-side surface S6 is concave. The fourth lens element E4 with positive refractive power has a concave object-side surface S7 and a convex image-side surface S8 at a paraxial region; at the circumference, the object-side surface S7 of the fourth lens element is concave, and the image-side surface S8 is convex. The fifth lens element E5 with negative refractive power has a concave object-side surface S9 and a convex image-side surface S10 at a paraxial region; at the circumference, the object-side surface S9 of the fifth lens element is concave, and the image-side surface S10 is convex. Filter E6 has an object side S11 and an image side S12. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.

Table 9 shows the surface type, radius of curvature, thickness, material, refractive index, abbe number, and effective focal length of each lens of the optical imaging system of example 5, where the unit of the radius of curvature, thickness, and effective focal length are all millimeters (mm).

TABLE 9

Effective focal length of optical imaging system in example 5Distance is EFL, and aperture value of optical imaging system is F_noThe field angle of the optical imaging system is FOV, the total optical length of the optical imaging system is TTL, and the numerical values are: f2.64 mm, F_NOFOV 80.40 (degrees) and TTL 3.64mm 1.64.

As can be seen from table 9, the object-side surface and the image-side surface of any one of the first lens element E1 through the fifth lens element E5 are aspheric. Table 10 below gives the conic coefficients k and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirrors S1-S10 in example 5.

Watch 10

The optical imaging system in embodiment 5 satisfies the following relationship:

(| SAG51| + SAG52)/CT5 ═ 0.98; the SAG51 is a distance from an intersection point of an object side surface S9 of the fifth lens E5 and an optical axis to an edge of an optically effective area of an object side surface S9 of the fifth lens E5 projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface S10 of the fifth lens E5 and the optical axis to an edge of an optically effective area of an image side surface S10 of the fifth lens E5 projected on the optical axis, and the CT5 is a central thickness of the fifth lens E5 on the optical axis.

(n1+n2)/f＝1.17mm^-1Wherein n1 is the refractive index of the first lens E1, n2 is the refractive index of the second lens E2, and f is the total effective focal length of the optical imaging system;

f12/f is 1.65, f12 is the effective focal length of the first lens and the second lens after being cemented, and f is the effective focal length of the optical imaging system. Alternatively, f12 is 4.33mm and f is 2.63 mm.

EPD/SD31 ═ 1.86, where EPD is the entrance pupil diameter of the optical imaging system, SD31 is the maximum effective radius of the object side S5 of the third lens E3;

(| f2| + | f3|)/R31 ═ 16.44, where f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and R31 is the radius of curvature at the paraxial position of the object-side surface S5 of the third lens E3;

(f1+ | f2| + | f3|)/f 10.83, wherein f1 is the effective focal length of the first lens E1, f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and f is the total effective focal length of the optical imaging system;

i R41/R51| ═ 4.07, where R41 is the radius of curvature at the paraxial region of the object-side surface S7 of the fourth lens E4, and R51 is the radius of curvature at the paraxial region of the object-side surface S9 of the fifth lens E5.

L R41/f 4 is 1.95, where R41 is the radius of curvature of the object side S7 of the fourth lens E4 at the paraxial region, and f4 is the effective focal length of the fourth lens E4;

TTL is 3.64mm, where TTL is a distance from the object-side surface S1 of the first lens element E1 to the imaging surface S13 of the optical imaging system;

The FOV is 80.4 °, where FOV is the maximum field angle of the optical imaging system.

Fig. 10A shows a spherical aberration curve of the optical imaging system of example 5, which represents the deviation of the convergent focus of light rays of different wavelengths after passing through the lens. Fig. 10B shows astigmatism curves of the optical imaging system of example 5, which represent meridional field curvature and sagittal field curvature. Fig. 10C shows a distortion curve of the optical imaging system of example 5, which represents distortion magnitude values corresponding to different image heights. As can be seen from fig. 10A to 10C, the optical imaging system according to embodiment 5 can achieve good imaging quality.

Example 6

An optical imaging system according to embodiment 6 of the present application is described below with reference to fig. 11 to 12C. Fig. 11 shows a schematic configuration diagram of an optical imaging system according to embodiment 5 of the present application.

As illustrated in fig. 11, the optical imaging system according to the exemplary embodiment of the present application includes, once from an object side to an image side: a stop ST0, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6, and an image forming surface S13.

The first lens element E1 with positive refractive power has a convex object-side surface S1 and a convex image-side surface S2 at a paraxial region; at the circumference, the object-side surface S1 of the first lens element is convex, and the image-side surface S2 is concave. The second lens element E2 with positive refractive power has a concave object-side surface S3 and a convex image-side surface S4 at a paraxial region; at the circumference, the object-side surface S3 of the second lens element is convex, and the image-side surface S4 is convex. The third lens element E3 with negative refractive power has a convex object-side surface S5 and a concave image-side surface S6 at a paraxial region; at the circumference, the object-side surface S5 of the third lens element is concave, and the image-side surface S6 is convex. The fourth lens element E4 with positive refractive power has a concave object-side surface S7 and a convex image-side surface S8 at a paraxial region; at the circumference, the object-side surface S7 of the fourth lens element is concave, and the image-side surface S8 is concave. The fifth lens element E5 with negative refractive power has a convex object-side surface S9 and a concave image-side surface S10 at a paraxial region; at the circumference, the object-side surface S9 of the fifth lens element is convex, and the image-side surface S10 is convex. Filter E6 has an object side S11 and an image side S12. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.

Table 11 shows the surface type, radius of curvature, thickness, material, refractive index, abbe number, and effective focal length of each lens of the optical imaging system of example 6, where the unit of the radius of curvature, thickness, and effective focal length are all millimeters (mm).

TABLE 11

The effective focal length of the optical imaging system in example 6 was EFL, and the aperture value of the optical imaging system was F_noThe angle of view of the optical imaging system is FOV, and the optical imaging system isThe total optical length of the image system is TTL, and the numerical value is as follows: f2.55 mm, F_NO2.2, FOV 82.00 (degrees), TTL 3.77 mm.

As can be seen from table 11, the object-side surface and the image-side surface of any one of the first lens element E1 through the fifth lens element E5 are aspheric. Table 12 below gives the conic coefficients k and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 that can be used for each of the aspherical mirror surfaces S1-S10 in example 6.

TABLE 12

The optical imaging system in embodiment 6 satisfies the following relationship:

(| SAG51| + SAG52)/CT5 ═ 1.10; the SAG51 is a distance from an intersection point of an object side surface S9 of the fifth lens E5 and an optical axis to an edge of an optically effective area of an object side surface S9 of the fifth lens E5 projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface S10 of the fifth lens E5 and the optical axis to an edge of an optically effective area of an image side surface S10 of the fifth lens E5 projected on the optical axis, and the CT5 is a central thickness of the fifth lens E5 on the optical axis.

(n1+n2)/f＝1.26mm^-1Wherein n1 is the refractive index of the first lens E1, n2 is the refractive index of the second lens E2, and f is the total effective focal length of the optical imaging system;

f12/f is 1.23, f12 is the effective focal length of the first lens and the second lens after being cemented, and f is the effective focal length of the optical imaging system. Alternatively, f12 is 3.13mm and f is 2.55 mm.

EPD/SD31 ═ 1.54, where EPD is the entrance pupil diameter of the optical imaging system, SD31 is the maximum effective radius of the object side S5 of the third lens E3;

(| f2| + | f3|)/R31 ═ 0.12, where f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and R31 is the radius of curvature at the paraxial position of the object-side surface S5 of the third lens E3;

(f1+ | f2| + | f3|)/f 11.06, wherein f1 is the effective focal length of the first lens E1, f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and f is the total effective focal length of the optical imaging system;

l R41/R51| -2.73, where R41 is the radius of curvature at the paraxial region of the object-side surface S7 of the fourth lens E4, and R51 is the radius of curvature at the paraxial region of the object-side surface S9 of the fifth lens E5.

1.202, wherein R41 is a curvature radius of an object side surface S7 of the fourth lens E4 at a paraxial position, and f4 is an effective focal length of the fourth lens E4;

TTL is 3.77mm, where TTL is a distance from the object-side surface S1 of the first lens element E1 to the imaging surface S13 of the optical imaging system;

n1 is 1.671, where n1 is the refractive index of the first lens E1, and the reference wavelength of light is 587.6 nm.

The FOV is 82.00 °, where FOV is the maximum field angle of the optical imaging system.

Fig. 12A shows a spherical aberration curve of the optical imaging system of example 6, which represents the deviation of the convergent focus of light rays of different wavelengths after passing through the lens. Fig. 12B shows astigmatism curves of the optical imaging system of example 6, which represent meridional field curvature and sagittal field curvature. Fig. 12C shows a distortion curve of the optical imaging system of embodiment 6, which represents distortion magnitude values corresponding to different image heights. As can be seen from fig. 12A to 10C, the optical imaging system according to embodiment 6 can achieve good imaging quality.

Example 7

An optical imaging system according to embodiment 7 of the present application is described below with reference to fig. 13 to 14C. Fig. 13 is a schematic structural view showing an optical imaging system according to embodiment 5 of the present application.

As illustrated in fig. 13, the optical imaging system according to the exemplary embodiment of the present application includes, once from an object side to an image side: a stop ST0, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6, and an image forming surface S13.

The first lens element E1 with positive refractive power has a convex object-side surface S1 and a concave image-side surface S2 at a paraxial region; at the circumference, the object-side surface S1 of the first lens element is convex, and the image-side surface S2 is concave. The second lens element E2 with positive refractive power has a convex object-side surface S3 and a convex image-side surface S4 at a paraxial region; at the circumference, the object-side surface S3 of the second lens element is convex, and the image-side surface S4 is convex. The third lens element E3 with negative refractive power has a convex object-side surface S5 and a concave image-side surface S6 at a paraxial region; at the circumference, the object-side surface S5 of the third lens element is convex, and the image-side surface S6 is concave. The fourth lens element E4 with positive refractive power has a concave object-side surface S7 and a convex image-side surface S8 at a paraxial region; at the circumference, the object-side surface S7 of the fourth lens element is concave, and the image-side surface S8 is convex. The fifth lens element E5 with negative refractive power has a concave object-side surface S9 and a concave image-side surface S10 at a paraxial region; at the circumference, the object-side surface S9 of the fifth lens element is concave, and the image-side surface S10 is convex. Filter E6 has an object side S11 and an image side S12. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.

Table 13 shows the surface type, radius of curvature, thickness, material, refractive index, abbe number, and effective focal length of each lens of the optical imaging system of example 7, where the unit of the radius of curvature, thickness, and effective focal length are all millimeters (mm).

Watch 13

The effective focal length of the optical imaging system in example 7 was EFL, and the aperture value of the optical imaging system was F_noThe field angle of the optical imaging system is FOV, the total optical length of the optical imaging system is TTL, and the numerical values are: f2.67 mm_NO2.15, FOV 79.00 (degrees), TTL 3.10 mm.

As can be seen from table 13, the object-side surface and the image-side surface of any one of the first lens element E1 through the fifth lens element E5 are aspheric. Table 14 below gives the conic coefficients k and the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 which can be used for each of the aspherical mirrors S1-S10 in example 7.

TABLE 14

The optical imaging system in embodiment 7 satisfies the following relationship:

(| SAG51| + SAG52)/CT5 ═ 3.26; the SAG51 is a distance from an intersection point of an object side surface S9 of the fifth lens E5 and an optical axis to an edge of an optically effective area of an object side surface S9 of the fifth lens E5 projected on the optical axis, the SAG52 is a distance from an intersection point of an image side surface S10 of the fifth lens E5 and the optical axis to an edge of an optically effective area of an image side surface S10 of the fifth lens E5 projected on the optical axis, and the CT5 is a central thickness of the fifth lens E5 on the optical axis.

(n1+n2)/f＝1.20mm^-1Wherein n1 is the refractive index of the first lens E1, n2 is the refractive index of the second lens E2, and f is the total effective focal length of the optical imaging system;

f12/f is 1.06, f12 is the effective focal length of the first lens and the second lens after being cemented, and f is the effective focal length of the optical imaging system. Alternatively, f12 is 2.84mm and f is 2.67 mm.

EPD/SD31 ═ 1.43, where EPD is the entrance pupil diameter of the optical imaging system, SD31 is the maximum effective radius of the object side S5 of the third lens E3;

(| f2| + | f3|)/R31 ═ 4.15, where f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and R31 is the radius of curvature at the paraxial position of the object-side surface S5 of the third lens E3;

f/| f3|, where f is the total effective focal length of the optical imaging system, and f3 is the effective focal length of the third lens E3, 0.15;

(f1+ | f2| + | f3|)/f 15.97, wherein f1 is the effective focal length of the first lens E1, f2 is the effective focal length of the second lens E2, f3 is the effective focal length of the third lens E3, and f is the total effective focal length of the optical imaging system;

l R41/R51| ═ 0.50, where R41 is the radius of curvature at the paraxial region of the object-side surface S7 of the fourth lens E4, and R51 is the radius of curvature at the paraxial region of the object-side surface S9 of the fifth lens E5.

L R41/f 4 is 1.36, where R41 is a curvature radius at a paraxial position of an object side S7 of the fourth lens E4, and f4 is an effective focal length of the fourth lens E4;

TTL is 3.10mm, where TTL is a distance from the object-side surface S1 of the first lens element E1 to the imaging surface S13 of the optical imaging system;

The FOV is 79.00 °, where FOV is the maximum field angle of the optical imaging system.

Fig. 14A shows a spherical aberration curve of the optical imaging system of example 7, which represents the deviation of the convergent focus of light rays of different wavelengths after passing through the lens. Fig. 14B shows astigmatism curves of the optical imaging system of example 7, which represent meridional field curvature and sagittal field curvature. Fig. 14C shows a distortion curve of the optical imaging system of example 7, which represents distortion magnitude values corresponding to different image heights. As can be seen from fig. 14A to 14C, the optical imaging system according to embodiment 7 can achieve good imaging quality

While the invention has been described with reference to specific embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. An optical imaging system, comprising, in order from an object side to an image side along an optical axis:

the optical imaging system satisfies the conditional expression:

0.5＜(|SAG51|+SAG52)/CT5＜3.5；

2. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: 1.0mm^-1＜(n1+n2)/f≤1.3mm^-1；

Wherein n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, and f is the effective focal length of the optical imaging system; the reference wavelength of light is 587.6 nm.

3. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: f12/f is more than 0.8 and less than 1.7;

wherein f12 is an effective focal length of the first lens and the second lens after being cemented, and f is an effective focal length of the optical imaging system.

4. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: 1.4 < EPD/SD31 < 2.0;

where EPD is the entrance pupil diameter of the optical imaging system and SD31 is the maximum effective radius of the object-side surface of the third lens.

5. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: (| f2| + | f3|)/R31< 57.0;

wherein f2 is the effective focal length of the second lens, f3 is the effective focal length of the third lens, and R31 is the radius of curvature at the paraxial region of the object side of the third lens.

6. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: f/| f3| < 0.70;

wherein f is an effective focal length of the optical imaging system, and f3 is an effective focal length of the third lens.

7. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: 6 < (f1+ | f2| + | f3|)/f < 46.0;

wherein f1 is an effective focal length of the first lens, f2 is an effective focal length of the second lens, f3 is an effective focal length of the third lens, and f is an effective focal length of the optical imaging system.

8. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: i R41/R51I < 4.0;

wherein R41 is a radius of curvature at the paraxial region of the object side surface of the fourth lens, and R51 is a radius of curvature at the paraxial region of the object side surface of the fifth lens.

9. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: r41/f 4 is more than or equal to 1.2 and less than 2.9;

wherein R41 is the radius of curvature at the paraxial region of the object side of the fourth lens, f4 is the effective focal length of the fourth lens.

10. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: 3.0< TTL < 4.0;

the image side of the optical imaging system is provided with an imaging surface, and TTL is the distance from the object side surface of the first lens to the imaging surface of the optical imaging system.

11. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: n1 > 1.535;

wherein n1 is the refractive index of the first lens, and the reference wavelength of light is 587.6 nm.

12. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: FOV is more than or equal to 70 degrees and less than or equal to 85 degrees;

wherein the FOV is a maximum field angle of the optical imaging system.

13. A lens barrel comprising a photosensitive element and the optical imaging system according to any one of claims 1 to 12, the photosensitive element being disposed on an image side of the optical imaging system.

14. An electronic apparatus comprising a body and the lens barrel of claim 13, the lens barrel being mounted on the body.