CN112835173A

CN112835173A - Optical imaging system, image capturing device and electronic equipment

Info

Publication number: CN112835173A
Application number: CN201911161887.1A
Authority: CN
Inventors: 杨健; 李明
Original assignee: Jiangxi Jingchao Optical Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2019-11-22
Filing date: 2019-11-22
Publication date: 2021-05-25

Abstract

The invention provides an optical imaging system, which comprises the following components in sequence from an object side to an image side: a first lens having an optical power; a second lens having a positive optical power; a third lens having a positive optical power; a fourth lens having an optical power; a fifth lens having optical power; a sixth lens having positive optical power; and a seventh lens having a negative optical power; wherein the optical imaging system satisfies the following relation: 1 < SD12/SD21 < 1.4; wherein SD12 is the effective half aperture of the image side surface of the first lens; SD21 is the second lens object side effective half aperture. The optical imaging system has small volume and larger light inlet quantity, can improve the dark light shooting condition, and has good imaging quality when shooting under the dark light condition. The invention also provides an image capturing device and electronic equipment.

Description

Optical imaging system, image capturing device and electronic equipment

Technical Field

The present disclosure relates to optical imaging technologies, and particularly to an optical imaging system, an image capturing device and an electronic apparatus.

Background

With the continuous development of the related camera shooting technology, the camera shooting function becomes a standard matching function of intelligent electronic products, the demand of consumers on electronic products with ideal camera shooting effect is higher and higher, and some high-pixel optical imaging systems have good camera shooting effect under the application of matching optimization software algorithm, so that excellent experience is brought to consumers. However, as the performance and size of a common photosensitive Device such as a Charge Coupled Device (CCD) or a Complementary Metal-Oxide Semiconductor (CMOS) Device are increased, the number of pixels of the photosensitive Device is increased and the size of the pixels is decreased, which puts higher demands on the miniaturization of the imaging lens, and puts higher demands on the amount of light entering the lens in environments with insufficient light, such as at night, in rainy days, and in sky. Meanwhile, in order to ensure high imaging quality of the optical lens, more lenses are needed to realize the high imaging quality, and more difficulties are inevitably brought to the miniaturization design of the lens. The existing optical imaging system is small in size and difficult to ensure high imaging quality in various complex environments.

Disclosure of Invention

In view of the above, the present invention provides an optical imaging system, which has a small size and a large light-entering amount, and can ensure good imaging quality even in a dark environment.

It is also necessary to provide an image capturing apparatus using the above optical imaging system.

In addition, it is necessary to provide an electronic device using the above-described orientation apparatus.

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

a first lens having an optical power;

a second lens having a positive optical power;

a third lens having a positive optical power;

a fourth lens having an optical power;

a fifth lens having optical power;

a sixth lens having positive optical power; and

a seventh lens having a negative optical power;

wherein the optical imaging system satisfies the following relation:

1＜SD12/SD21＜1.4；

wherein SD12 is the effective half aperture of the image side surface of the first lens; SD21 is the second lens object side effective half aperture.

When 1 < SD12/SD21 < 1.4, the size of the front part of the optical imaging system can be effectively reduced.

The object-side surface and the image-side surface of the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, the sixth lens element and the seventh lens element are aspheric. And the aspheric lens is favorable for converging light rays and imaging. Can be easily manufactured into shapes other than spherical surfaces, obtain more control variables, obtain good imaging by using fewer lenses, further reduce the number of lenses and meet the requirement of miniaturization.

The object side surface of the first lens is a concave surface at the paraxial region, and the image side surface is a convex surface at the paraxial region. This reduces the angle of incidence of the light.

The second lens element has a convex object-side surface and a concave image-side surface. Is used for matching with the first lens to correct the edge chromatic aberration of the optical imaging system.

The circumference of the object side surface of the third lens is a convex surface; the image side surface is convex at the position close to the optical axis and the circumference. Therefore, the chromatic aberration and spherical aberration of the system can be further corrected.

The object side surface of the fourth lens is a concave surface at the position close to the optical axis, and the circumference of the fourth lens is a convex surface; the image side surface is convex at the position close to the optical axis and concave at the circumference. Therefore, the distance between the third lens and the fourth lens can be reduced, and the effective caliber of the fourth lens is reduced, so that the molding difficulty of the optical imaging system is reduced.

The object side surface of the fifth lens is concave at the paraxial axis and the circumference; the image side surface is convex at the circumference. Thus, the aberration of the marginal field ray can be reduced, and the marginal ray can be converged as much as possible.

The object side surface of the sixth lens is convex at the paraxial region and the circumference; the periphery of the image side surface is a concave surface. Therefore, the internal view field light can be converged, and the incidence angle of the main light is reduced.

The object side surface of the seventh lens is a convex surface at the position close to the optical axis, and the circumference of the seventh lens is a concave surface; the image side surface is concave at the paraxial axis and convex at the circumference. The lens is used for weakening spherical aberration, coma aberration and astigmatism generated after light rays pass through the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens.

The optical imaging system further comprises an infrared filter, and the infrared filter is located between the seventh lens and the imaging surface. The infrared filter can filter out light in an infrared band, reduce part of ghost image stray light and play a certain role in protecting the photosensitive element.

Wherein the optical imaging system further comprises a diaphragm positioned between the second lens and the third lens. The diaphragm is beneficial to balancing the spherical aberration in the sagittal direction, and the MTF performance of the optical imaging system is improved.

Wherein the optical imaging system satisfies the following conditional expression:

TTL/Imgh＜1.3；

wherein, TTL is a distance on an optical axis from the object-side surface of the first lens element to an imaging surface of the optical imaging system, and Imgh is a half of a diagonal length of an effective pixel area on the imaging surface.

When TTL/Imgh is less than 1.3, the optical imaging system is more miniaturized.

2＜f/R14＜4；

wherein f is an effective focal length of the optical imaging system, and R14 is a curvature radius of an image side surface of the seventh lens.

When 2 < f/R14 < 4, the internal field chief ray angle of the photosensitive element can be better matched.

Fno＜2；

wherein Fno is an f-number of the optical imaging system.

When Fno < 2, the optical imaging system can meet the requirement of miniaturization, and simultaneously can ensure a large aperture, so that the optical imaging system has enough light incoming quantity, the shot image is clearer, and the shooting of high-quality object space scenes with low brightness, such as night scenes, starry sky scenes and the like, is realized.

TTL/f＜1.6；

wherein, TTL is the distance between the object side surface of the first lens and the imaging surface of the optical system on the optical axis; f is the effective focal length of the optical system.

When TTL/f is less than 1.6, the optical imaging system can meet the miniaturization requirement.

1＜(R13+R14)/(R13－R14)＜4；

wherein R13 is a radius of curvature of the object-side surface of the seventh lens, and R14 is a radius of curvature of the image-side surface of the seventh lens.

When 1 < (R13+ R14)/(R13-R14) < 4, the radius of curvature of the object side surface of the third lens and the radius of curvature of the image side surface S6 are more suitable, so that the incident angle can be reasonably increased to meet the requirement of the optical imaging system on image height, and meanwhile, the system sensitivity is reduced, and the assembly stability of the optical imaging system is improved.

0.1＜T45/CT5＜1；

wherein T45 is the distance between the fourth lens and the fifth lens on the optical axis, and CT5 is the center thickness of the fifth lens.

When the ratio of 0.1 < T45/CT5 < 1, the structural arrangement of the optical imaging system is facilitated.

0＜T34/CT4＜0.82；

Wherein T34 is the distance between the third lens and the fourth lens on the optical axis, and CT4 is the center thickness of the fourth lens.

When the value is more than 0 and less than T34/CT4 and less than 0.82, the light deflection angle is favorably reduced, and the sensitivity of the optical imaging system 100 is reduced.

The present invention also provides an image capturing device, comprising:

the optical imaging system described above; and

a photosensitive element located on an image side of the optical imaging system.

The present invention also provides an electronic device, comprising:

an apparatus main body and;

the image capturing device is mounted on the main body of the apparatus.

Therefore, the optical imaging system has small volume and larger light inlet amount through the design of focal power, surface type and the like of the seven lenses, can improve the dark light shooting condition, and has good imaging quality in the dark light shooting condition.

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. 1-1 is a schematic structural view of an optical imaging system according to a first embodiment of the present invention.

Fig. 1-2 are graphs of spherical aberration, astigmatism and distortion of the optical imaging system of the first embodiment of the present invention from left to right in sequence.

Fig. 2-1 is a schematic structural view of an optical imaging system of a second embodiment of the present invention.

Fig. 2-2 is a graph showing the spherical aberration, astigmatism and distortion of the optical imaging system according to the second embodiment of the present invention from left to right.

Fig. 3-1 is a schematic structural view of an optical imaging system according to a third embodiment of the present invention.

Fig. 3-2 is a graph showing the spherical aberration, astigmatism and distortion of the optical imaging system according to the third embodiment of the present invention from left to right.

Fig. 4-1 is a schematic structural view of an optical imaging system according to a fourth embodiment of the present invention.

Fig. 4-2 is a graph showing the spherical aberration, astigmatism and distortion of the optical imaging system according to the fourth embodiment of the present invention from left to right.

Fig. 5-1 is a schematic structural view of an optical imaging system according to a fifth embodiment of the present invention.

Fig. 5-2 is a graph showing the spherical aberration, astigmatism and distortion of the optical imaging system according to the fifth embodiment of the present invention from left to right.

Fig. 6-1 is a schematic structural view of an optical imaging system according to a sixth embodiment of the present invention.

Fig. 6-2 is a graph showing the spherical aberration, astigmatism and distortion of the optical imaging system according to the sixth embodiment of the present invention from left to right.

Fig. 7 is a schematic structural diagram of an image capturing apparatus according to an embodiment of the invention.

Fig. 8 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

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.

Referring to fig. 1-1, fig. 2-1, fig. 3-1, fig. 4-1, fig. 5-1, and fig. 6-1, an optical imaging system 100 according to an embodiment of the present invention is applied to a camera of a miniature digital product such as a mobile phone, an unmanned aerial vehicle, and the like, and includes, in order from an object side to an image side, a first lens L1 having a positive power, a second lens L2 having a positive power, a third lens L3 having a positive power, a fourth lens L4 having a positive power, a fifth lens L5 having a positive power, a sixth lens L6 having a positive power, and a seventh lens L7 having a negative power. The optical imaging system satisfies the following relation:

1＜SD12/SD21＜1.4；

wherein SD12 is the effective half aperture of the image side surface of the first lens L1; SD21 is the second lens L2 object-side effective half aperture.

When 1 < SD12/SD21 < 1.4, the size of the front of the optical imaging system 100 can be effectively reduced.

The optical imaging system 100 of the invention has small head size, larger light transmission aperture, larger light inlet quantity, can improve the dark light shooting condition, and has good imaging quality when shooting under the dark light condition.

Optionally, the first lens element L1 is made of plastic or glass and has an object-side surface S1 and an image-side surface S2. The object-side surface S1 and the image-side surface S2 are both aspheric. The object side surface S1 is concave near the optical axis and may be convex or concave at the circumference. The image side surface S2 is convex at the paraxial region and may be convex or concave at the peripheral region. The first lens L1 may have a positive power or a negative power. The first lens L1 is an aspheric lens, which is favorable for converging light rays and imaging. Can be easily manufactured into shapes other than spherical surfaces, obtain more control variables, obtain good imaging by using fewer lenses, further reduce the number of lenses and meet the requirement of miniaturization. The surface shapes of the object side surface S1 and the image side surface S2 of the first lens L1 are designed to reduce the incident angle of light.

Optionally, the second lens element L2 is made of plastic or glass and has an object-side surface S3 and an image-side surface S4. The object-side surface S3 and the image-side surface S4 are both aspheric. The object side surface S3 is convex near the optical axis and may be convex or concave at the circumference. The image side surface S4 is concave near the optical axis and may be convex or concave at the circumference. The second lens L2 is an aspheric lens, which can be easily made into shapes other than spherical, so as to obtain more control variables, thereby being beneficial to reducing aberration and obtaining good imaging with fewer lenses; further, the number of lenses is reduced, and the miniaturization is satisfied. The second lens L2 has a face shape of the object-side surface S3 and the image-side surface S4 designed to correct the edge chromatic aberration of the optical imaging system 100 in cooperation with the first lens.

Optionally, the third lens element L3 is made of plastic or glass and has an object-side surface S5 and an image-side surface S6. The object-side surface S5 and the image-side surface S6 are both aspheric. The object side surface S5 may be convex or concave near the optical axis and convex at the circumference. The image side surface S6 is convex both near the optical axis and at the circumference. The third lens L3 can effectively reduce the curvature of field and distortion of the system, and improve the imaging quality. The third lens adopts an aspheric lens, can be easily manufactured into shapes other than a spherical surface, obtains more control variables, is beneficial to reducing aberration, and has the advantage of obtaining good imaging by using a small number of lenses; further, the number of lenses is reduced, and the miniaturization is satisfied. The surface shape design of the object side surface S5 and the image side surface S6 of the third lens L3 can further correct the chromatic aberration and spherical aberration of the system.

Optionally, the fourth lens element L4 is made of plastic or glass and has an object-side surface S7 and an image-side surface S8. The object-side surface S7 and the image-side surface S8 are both aspheric. The object side surface S7 is concave near the optical axis and convex at the circumference. The image side surface S8 is convex near the optical axis and concave at the circumference. The fourth lens L4 may have a positive power or a negative power. The aspheric lens of the lens can be easily manufactured into a shape other than a spherical surface, more control variables are obtained, the aberration is favorably reduced, and the advantage of good imaging is obtained by using a small number of lenses; further, the number of lenses is reduced, and the miniaturization is satisfied. The surface shape design of the object-side surface S7 and the image-side surface S8 of the fourth lens L4 can reduce the distance between the third lens L3 and the fourth lens L4, and reduce the effective aperture of the fourth lens L4, thereby reducing the difficulty in molding the optical imaging system 100.

Optionally, the fifth lens element L5 is made of plastic or glass and has an object-side surface S9 and an image-side surface S10. The object-side surface S9 and the image-side surface S10 are both aspheric. The object side surface S9 is concave both near the optical axis and at the circumference. The image side surface S10 may be convex or concave near the optical axis and convex at the circumference. The fifth lens L5 may have a positive power or a negative power. The aspheric lens of the lens can be easily manufactured into a shape other than a spherical surface, more control variables are obtained, the aberration is favorably reduced, and the advantage of good imaging is obtained by using a small number of lenses; further, the number of lenses is reduced, and the miniaturization is satisfied. The surface type design of the object-side surface S9 and the image-side surface S10 of the fifth lens L5 can reduce the aberration of the marginal field rays and converge the marginal rays as much as possible.

Optionally, the sixth lens element L6 is made of plastic or glass and has an object-side surface S11 and an image-side surface S12. The object-side surface S11 and the image-side surface S12 are both aspheric. The object side surface S11 is convex both near the optical axis and at the circumference. The image side surface S12 may be convex or concave near the optical axis and concave at the circumference. The aspheric lens of the lens can be easily manufactured into a shape other than a spherical surface, more control variables are obtained, the aberration is favorably reduced, and the advantage of good imaging is obtained by using a small number of lenses; further, the number of lenses is reduced, and the miniaturization is satisfied. The planar design of the object-side surface S11 and the image-side surface S12 of the sixth lens element L6 can converge the internal field rays and reduce the incident angle of the chief rays.

Optionally, the seventh lens element L7 is made of plastic or glass and has an object-side surface S13 and an image-side surface S14. The object-side surface S13 and the image-side surface S14 are both aspheric. The object side surface S13 is convex near the optical axis and concave at the circumference. The image side surface S14 is concave near the optical axis and convex at the circumference. The aspheric lens of the lens can be easily manufactured into a shape other than a spherical surface, more control variables are obtained, the aberration is favorably reduced, and the advantage of good imaging is obtained by using a small number of lenses; further, the number of lenses is reduced, and the miniaturization is satisfied. The surface shapes of the object-side surface S13 and the image-side surface S14 of the seventh lens element L7 are designed to reduce spherical aberration, coma aberration and astigmatism generated by light passing through the first lens element L1, the second lens element L2, the third lens element L3, the fourth lens element L4, the fifth lens element L5 and the sixth lens element L6.

In some embodiments, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are all made of plastic. In this case, the weight of the optical imaging system 100 can be reduced and the production cost can be reduced.

In other embodiments, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are made of glass. The optical imaging system 100 can withstand higher temperature and has better optical performance.

In other embodiments, the first lens L1 is made of glass, and the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are made of plastic. The first lens closest to the object side is made of glass, so that the first lens can better withstand the influence of the ambient temperature on the object side, and meanwhile, the other lenses are made of plastic, so that the weight of the optical imaging system 100 can be well reduced, and the production cost can be reduced.

Optionally, the optical imaging system 100 further includes a diaphragm 10, and the diaphragm 10 is located between the second lens L2 and the third lens L3. The diaphragm is beneficial to balancing spherical aberration in the sagittal direction, and improves MTF (Modulation Transfer Function) performance of the optical imaging system 100.

Optionally, the optical imaging system 100 further comprises an infrared filter 30. The infrared filter has a first face 31 and a second face 32. The infrared filter 30 is made of glass and is located between the seventh lens element L7 and the image plane 50. The infrared filter 30 can filter out light in an infrared band, reduce a part of ghost image stray light, and also can protect a photosensitive element to a certain extent.

In some embodiments, the optical imaging system 100 satisfies the following conditional expression:

TTL/Imgh＜1.3；

wherein TTL is an axial distance from the object-side surface S1 of the first lens element L1 to the imaging surface 50 of the optical imaging system, and Imgh is a half of a diagonal length of an effective pixel area on the imaging surface 50.

That is, TTL/Imgh can be any value less than 1.3, such as 0.1, 0.2, 0.5, 0.7, 0.9, 1.1, 1.2, 1.29, and the like.

2＜f/R14＜4；

where f is the effective focal length of the optical imaging system 100, and R14 is the curvature radius of the image-side surface S14 of the seventh lens L7.

That is, f/R14 may be any value between 2 and 4, such as 2.1, 2.5, 2.8, 3.0, 3.2, 3.6, 3.9, and the like.

Fno＜2；

where Fno is the f-number of the optical imaging system 100.

That is, Fno can be any number less than 2, such as 0.1, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.9, and the like.

When Fno < 2, the optical imaging system 100 can satisfy the requirement of miniaturization, and simultaneously can ensure a large aperture, so that the optical imaging system 100 has enough light incoming quantity, the shot image is clearer, and the shooting of high-quality object space scenes with low brightness, such as night scenes, starry sky scenes and the like, is realized.

TTL/f＜1.6；

That is, TTL/f can be any value less than 1.6, such as 0.1, 0.5, 0.6, 0.8, 1.0, 1.2, 1.5, and the like.

When TTL/f is less than 1.6, the optical imaging system 100 can meet the miniaturization requirement.

1＜(R13+R14)/(R13－R14)＜4；

That is, (R13+ R14)/(R13-R14) may be any of 1 and 4, for example, 1.1, 1.5, 2.1, 2.5, 3.0, 3.5, 3.9, etc.

When 1 < (R13+ R14)/(R13-R14) < 4, the curvature radius of the object-side surface S5 and the curvature radius of the image-side surface S6 of the third lens L3 are proper, so that the incident angle can be reasonably increased to meet the requirement of the optical imaging system 100 on image height, and meanwhile, the system sensitivity is reduced, and the assembly stability of the optical imaging system is improved.

0.1＜T45/CT5＜1；

t45 is the distance between the fourth lens L4 and the fifth lens L5 on the optical axis, and CT5 is the center thickness of the fifth lens L5.

That is, T45/CT5 may be any value between 0.1 and 1, such as 0.11, 0.3, 0.5, 0.7, 0.8, 0.85, 0.9, 0.99, etc.

When 0.1 < T45/CT5 < 1, the structural arrangement of the optical imaging system 100 is facilitated.

0＜T34/CT4＜0.82；

wherein T34 is the distance between the third lens L3 and the fourth lens L4 on the optical axis, and CT4 is the center thickness of the fourth lens L4.

That is, T34/CT4 may be any value between 0 and 0.82, such as 0.01, 0.11, 0.3, 0.5, 0.7, 0.8, etc.

When the value is more than 0 and less than T34/CT4 and less than 0.82, the light deflection angle is favorably reduced, and the sensitivity of the optical imaging system is reduced.

The optical imaging system 100 of the present invention is described in further detail below with reference to specific embodiments.

First embodiment

Referring to fig. 1-1 and fig. 1-2, wherein fig. 1-1 is a schematic structural diagram of an optical imaging system 100 according to a first embodiment, and fig. 1-2 are graphs of spherical aberration, astigmatism and distortion of the first embodiment of the invention from left to right. As can be seen from fig. 1-1, the optical imaging system 100 of the present embodiment includes, in order from an object side to an image side, a first lens L1 with negative power, a second lens L2 with positive power, a stop 10, a third lens L3 with positive power, a fourth lens L4 with negative power, a fifth lens L5 with negative power, a sixth lens L6 with positive power, a seventh lens L7 with negative power, an infrared filter 30, and an image plane 50.

The first lens element L1 is made of plastic material, and both the object-side surface S1 and the image-side surface S2 are aspheric. The object side surface S1 is concave near the optical axis and convex at the circumference. The image side surface S2 is convex near the optical axis and concave at the circumference.

The second lens element L2 is made of plastic material, and both the object-side surface S3 and the image-side surface S4 are aspheric. The object side surface S3 is convex near the optical axis and concave at the circumference. The image side surface S4 is concave near the optical axis and concave at the circumference.

The third lens element L3 is made of plastic material, and both the object-side surface S5 and the image-side surface S6 are aspheric. The object-side surface S5 is convex near the optical axis and convex at the circumference. The image side surface S6 is convex both near the optical axis and at the circumference.

The fourth lens element L4 is made of plastic material, and both the object-side surface S7 and the image-side surface S8 are aspheric. The object side surface S7 is concave near the optical axis and convex at the circumference. The image side surface S8 is convex near the optical axis and concave at the circumference.

The fifth lens element L5 is made of plastic material, and both the object-side surface S9 and the image-side surface S10 are aspheric. The object side surface S9 is concave both near the optical axis and at the circumference. The image side surface S10 is convex near the optical axis and convex at the circumference.

The sixth lens element L6 is made of plastic material, and both the object-side surface S11 and the image-side surface S12 are aspheric. The object side surface S11 is convex both near the optical axis and at the circumference. The image side surface S12 is concave near the optical axis and concave at the circumference.

The seventh lens element L7 is made of plastic material, and both the object-side surface S13 and the image-side surface S14 are aspheric. The object side surface S13 is convex near the optical axis and concave at the circumference. The image side surface S14 is concave near the optical axis and convex at the circumference.

In this embodiment, TTL ═ 6.88, Imgh ═ 5.32, and TTL/Imgh ═ 1.29; f is 4.38, R14 is 1.24, f/R14 is 3.53; FNO 1.88; SD12 ═ 1.85, SD21 ═ 1.51, SD12/SD21 ═ 1.227; TTL/f is 1.57; r13 ═ 2.73, R14 ═ 1.24, (R13+ R14)/(R13-R14) ═ 2.66; t45-0.52, CT 5-0.71, T45/CT 5-0.74; t34-0.14, CT 4-0.36, and T34/CT 4-0.38.

In the present embodiment, the optical imaging system 100 satisfies the conditions of table 1 and table 2 below.

The FOV in table 1 is the angle of field of the optical imaging system 100 in the diagonal direction.

Table 2 shows aspheric data of the first embodiment, where k is a conic coefficient of each surface, and A4-A20 are aspheric coefficients of 4 th to 20 th order of each surface.

As can be seen from fig. 1-2, the optical imaging system 100 of the present invention has a higher pixel size while satisfying miniaturization.

Second embodiment

Referring to fig. 2-1 and 2-2, wherein fig. 2-1 is a schematic structural diagram of an optical imaging system 100 according to a second embodiment, and fig. 2-2 is a graph of spherical aberration, astigmatism and distortion in the second embodiment of the invention from left to right. As can be seen from fig. 2-1, the optical imaging system 100 of the present embodiment includes, in order from the object side to the image side, a first lens L1 with negative power, a second lens L2 with positive power, a stop 10, a third lens L3 with positive power, a fourth lens L4 with negative power, a fifth lens L5 with negative power, a sixth lens L6 with positive power, a seventh lens L7 with negative power, an infrared filter 30, and an image plane 50.

The second lens element L2 is made of plastic material, and both the object-side surface S3 and the image-side surface S4 are aspheric. The object-side surface S3 is convex near the optical axis and convex at the circumference. The image side surface S4 is concave near the optical axis and convex at the circumference.

The third lens element L3 is made of plastic material, and both the object-side surface S5 and the image-side surface S6 are aspheric. The object side surface S5 is concave near the optical axis and convex at the circumference. The image side surface S6 is convex both near the optical axis and at the circumference.

The sixth lens element L6 is made of plastic material, and both the object-side surface S11 and the image-side surface S12 are aspheric. The object side surface S11 is convex both near the optical axis and at the circumference. The image side surface S12 is convex near the optical axis and concave at the circumference.

In this embodiment, TTL ═ 6.88, Imgh ═ 5.32, and TTL/Imgh ═ 1.29; f is 4.38, R14 is 1.27, f/R14 is 3.45; FNO 1.88; SD12 ═ 1.60, SD21 ═ 1.37, SD12/SD21 ═ 1.168; TTL/f is 1.57; r13 ═ 2.64, R14 ═ 1.27, (R13+ R14)/(R13-R14) ═ 2.85; t45-0.56, CT 5-0.65, T45/CT 5-0.87; t34-0.13, CT 4-0.36, and T34/CT 4-0.37.

In the present embodiment, the optical imaging system 100 satisfies the conditions of tables 3 and 4 below.

The FOV in table 3 is the angle of field of the optical imaging system 100 in the diagonal direction.

Table 4 shows aspheric data of the second embodiment, where k is a conic coefficient of each surface and A4-A20 are aspheric coefficients of 4 th to 20 th order of each surface.

As can be seen from fig. 2-2, the optical imaging system 100 of the present invention has a higher pixel size while satisfying miniaturization.

Third embodiment

Referring to fig. 3-1 and 3-2, wherein fig. 3-1 is a schematic structural diagram of an optical imaging system 100 according to a third embodiment, and fig. 3-2 is a graph of spherical aberration, astigmatism and distortion in the third embodiment of the invention from left to right. As can be seen from fig. 3-1, the optical imaging system 100 of the present embodiment includes, in order from the object side to the image side, a first lens L1 with negative power, a second lens L2 with positive power, a stop 10, a third lens L3 with positive power, a fourth lens L4 with negative power, a fifth lens L5 with negative power, a sixth lens L6 with positive power, a seventh lens L7 with negative power, an infrared filter 30, and an imaging plane 50.

The fifth lens element L5 is made of plastic material, and both the object-side surface S9 and the image-side surface S10 are aspheric. The object side surface S9 is concave both near the optical axis and at the circumference. The image side surface S10 is concave near the optical axis and convex at the circumference.

In this embodiment, TTL ═ 6.88, Imgh ═ 5.32, and TTL/Imgh ═ 1.29; f is 4.39, R14 is 1.29, f/R14 is 3.39; FNO 1.88; SD12 ═ 1.85, SD21 ═ 1.51, SD12/SD21 ═ 1.229; TTL/f is 1.57; r13 ═ 2.73, R14 ═ 1.29, (R13+ R14)/(R13-R14) ═ 2.80; t45-0.54, CT 5-0.66, T45/CT 5-0.82; t34-0.14, CT 4-0.34, and T34/CT 4-0.40.

In the present embodiment, the optical imaging system 100 satisfies the conditions of tables 5 and 6 below.

The FOV in table 5 is the angle of field of the optical imaging system 100 in the diagonal direction.

Table 6 shows aspheric data of the third embodiment, where k is a conic coefficient of each surface and A4-A20 are aspheric coefficients of 4 th to 20 th order of each surface.

As can be seen from fig. 3-2, the optical imaging system 100 of the present invention has a higher pixel size while satisfying miniaturization.

Fourth embodiment

Referring to fig. 4-1 and 4-2, wherein fig. 4-1 is a schematic structural diagram of an optical imaging system 100 according to a fourth embodiment, and fig. 4-2 is a graph of spherical aberration, astigmatism and distortion in the fourth embodiment of the invention from left to right. As can be seen from fig. 4-1, the optical imaging system 100 of the present embodiment includes, in order from the object side to the image side, a first lens L1 with positive power, a second lens L2 with positive power, a stop 10, a third lens L3 with positive power, a fourth lens L4 with negative power, a fifth lens L5 with negative power, a sixth lens L6 with positive power, a seventh lens L7 with negative power, an infrared filter 30, and an imaging plane 50.

The second lens element L2 is made of plastic material, and both the object-side surface S3 and the image-side surface S4 are aspheric. The object side surface S3 is convex near the optical axis and concave at the circumference. The image side surface S4 is concave near the optical axis and convex at the circumference.

In this embodiment, TTL ═ 6.88, Imgh ═ 5.32, and TTL/Imgh ═ 1.29; f is 4.38, R14 is 1.30, f/R14 is 3.38; FNO 1.9; SD12 ═ 1.83, SD21 ═ 1.48, SD12/SD21 ═ 1.239; TTL/f is 1.57; r13 ═ 2.93, R14 ═ 1.30, (R13+ R14)/(R13-R14) ═ 2.56; t45-0.53, CT 5-0.69, T45/CT 5-0.77; t34-0.14, CT 4-0.43, and T34/CT 4-0.32.

In the present embodiment, the optical imaging system 100 satisfies the conditions of the following tables 7 and 8.

The FOV in table 7 is the angle of field of the optical imaging system 100 in the diagonal direction.

Table 8 shows aspheric data of the fourth embodiment, where k is a conic coefficient of each surface and A4-A20 are aspheric coefficients of 4 th to 20 th order of each surface.

As can be seen from fig. 4-2, the optical imaging system 100 of the present invention has a higher pixel size while satisfying miniaturization.

Fifth embodiment

Referring to fig. 5-1 and 5-2, wherein fig. 5-1 is a schematic structural diagram of an optical imaging system 100 according to a fifth embodiment, and fig. 5-2 is a graph of spherical aberration, astigmatism and distortion in the fifth embodiment of the invention from left to right. As can be seen from fig. 5-1, the optical imaging system 100 of the present embodiment includes, in order from the object side to the image side, a first lens L1 with negative power, a second lens L2 with positive power, a stop 10, a third lens L3 with positive power, a fourth lens L4 with positive power, a fifth lens L5 with negative power, a sixth lens L6 with positive power, a seventh lens L7 with negative power, an infrared filter 30, and an imaging plane 50.

The first lens element L1 is made of plastic material, and both the object-side surface S1 and the image-side surface S2 are aspheric. The object side surface S1 is concave near the optical axis and concave at the circumference. The image side surface S2 is convex near the optical axis and convex at the circumference.

The second lens element L2 is made of plastic material, and both the object-side surface S3 and the image-side surface S4 are aspheric. The object-side surface S3 is convex near the optical axis and convex at the circumference. The image side surface S4 is concave near the optical axis and concave at the circumference.

In this embodiment, TTL ═ 6.88, Imgh ═ 5.32, and TTL/Imgh ═ 1.29; f is 4.40, R14 is 1.44, f/R14 is 3.05; FNO 1.95; SD12 ═ 1.88, SD21 ═ 1.49, SD12/SD21 ═ 1.265; TTL/f is 1.56; r13 ═ 4.07, R14 ═ 1.44, (R13+ R14)/(R13-R14) ═ 2.10; t45 ═ 0.17, CT5 ═ 0.69, T45/CT5 ═ 0.25; t34-0.25, CT 4-0.34, and T34/CT 4-0.76.

In the present embodiment, the optical imaging system 100 satisfies the conditions of tables 9 and 10 below.

The FOV in table 9 is the angle of field of the optical imaging system 100 in the diagonal direction.

Table 10 shows aspheric data of the fifth embodiment, where k is a conic coefficient of each surface and A4-A20 are aspheric coefficients of 4 th to 20 th order of each surface.

As can be seen from fig. 5-2, the optical imaging system 100 of the present invention has a higher pixel size while satisfying miniaturization.

Sixth embodiment

Referring to fig. 6-1 and 6-2, wherein fig. 6-1 is a schematic structural diagram of an optical imaging system 100 according to a sixth embodiment, and fig. 6-2 is a graph of spherical aberration, astigmatism and distortion in the sixth embodiment of the invention from left to right. As can be seen from fig. 6-1, the optical imaging system 100 of the present embodiment includes, in order from the object side to the image side, a first lens L1 with negative power, a second lens L2 with positive power, a stop 10, a third lens L3 with positive power, a fourth lens L4 with negative power, a fifth lens L5 with positive power, a sixth lens L6 with positive power, a seventh lens L7 with negative power, an infrared filter 30, and an imaging plane 50.

In this embodiment, TTL ═ 6.88, Imgh ═ 5.32, and TTL/Imgh ═ 1.29; f is 4.39, R14 is 1.30, f/R14 is 3.36; FNO 1.88; SD12 ═ 1.85, SD21 ═ 1.51, SD12/SD21 ═ 1.23; TTL/f is 1.57; r13 ═ 2.82, R14 ═ 1.30, (R13+ R14)/(R13-R14) ═ 2.72; t45-0.55, CT 5-0.73, T45/CT 5-0.76; t34-0.13, CT 4-0.34, and T34/CT 4-0.38.

In the present embodiment, the optical imaging system 100 satisfies the conditions of tables 11 and 12 below.

The FOV in table 11 is the angle of field of the optical imaging system 100 in the diagonal direction.

Table 12 shows aspheric data of the sixth embodiment, where k is a conic coefficient of each surface, and a 4-a 20 are aspheric coefficients of 4 th to 20 th orders of each surface.

As can be seen from fig. 6-2, the optical imaging system 100 of the present invention has a higher pixel size while satisfying miniaturization.

As shown in fig. 7, the present invention further provides an image capturing device 200 including the optical imaging system 100 of the present invention and a photosensitive element 210. The photosensitive element 210 is located on the image side of the optical imaging system 100.

The photosensitive element 210 of the present invention may be a Charge Coupled Device (CCD) or a Complementary Metal-Oxide Semiconductor (CMOS Sensor).

For other descriptions of the image capturing device 200, please refer to the above description, which is not repeated herein.

As shown in fig. 8, the present invention further provides an electronic apparatus 300, which includes an apparatus main body 310 and the image capturing device 200 of the present invention. The orientation device 200 is mounted on the apparatus body 310.

The electronic device 300 of the present invention includes, but is not limited to, a computer, a notebook computer, a tablet computer, a mobile phone, a camera, a smart band, a smart watch, smart glasses, a vehicle-mounted camera product, and the like.

While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. 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:

a first lens having an optical power;

a second lens having a positive optical power;

a third lens having a positive optical power;

a fourth lens having an optical power;

a fifth lens having optical power;

a sixth lens having positive optical power; and

a seventh lens having a negative optical power;

wherein the optical imaging system satisfies the following relation:

1＜SD12/SD21＜1.4；

2. The optical imaging system of claim 1, wherein the object-side surface and the image-side surface of the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, the sixth lens element and the seventh lens element are aspheric.

3. The optical imaging system of claim 1, wherein the first lens element has a concave object-side surface at a paraxial region and a convex image-side surface at a paraxial region.

4. The optical imaging system of claim 1, wherein the second lens element has a convex object-side surface at a paraxial region and a concave image-side surface at a paraxial region.

5. The optical imaging system of claim 1, wherein the third lens is convex at the object side circumference; the image side surface is convex at the position close to the optical axis and the circumference.

6. The optical imaging system of claim 1, wherein the fourth lens element has a concave object-side surface near the optical axis and a convex object-side surface at a circumference; the image side surface is convex at the position close to the optical axis and concave at the circumference.

7. The optical imaging system of claim 1, wherein the object side surface of the fifth lens is concave at the paraxial axis and at the circumference; the image side surface is convex at the circumference.

8. The optical imaging system of claim 1, wherein the object side surface of the sixth lens is convex both near the optical axis and at the circumference; the periphery of the image side surface is a concave surface.

9. The optical imaging system of claim 1, wherein the seventh lens element has a convex object-side surface at a position near the optical axis and a concave object-side surface at a circumference; the image side surface is concave at the paraxial axis and convex at the circumference.

10. The optical imaging system of claim 1, further comprising an infrared filter between the seventh lens and an imaging surface.

11. The optical imaging system of any of claims 1-10, further comprising an optical stop positioned between the second lens and the third lens.

12. The optical imaging system of claim 11, wherein the optical imaging system satisfies the following conditional expression:

TTL/Imgh＜1.3；

13. The optical imaging system of claim 11, wherein the optical imaging system satisfies the following conditional expression:

2＜f/R14＜4；

14. The optical imaging system of claim 11, wherein the optical imaging system satisfies the following conditional expression:

Fno＜2；

wherein Fno is an f-number of the optical imaging system.

15. The optical imaging system of claim 11, wherein the optical imaging system satisfies the following conditional expression:

TTL/f＜1.6；

16. The optical imaging system of claim 11, wherein the optical imaging system satisfies the following conditional expression:

1＜(R13+R14)/(R13－R14)＜4；

17. The optical imaging system of claim 11, wherein the optical imaging system satisfies the following conditional expression:

0.1＜T45/CT5＜1；

18. The optical imaging system of claim 11, wherein the optical imaging system satisfies the following conditional expression:

0＜T34/CT4＜0.82；

19. An image capturing apparatus, comprising:

the optical imaging system of any one of claims 1-18; and

20. An electronic device, comprising:

an apparatus main body and;

the image capturing device as claimed in claim 19, wherein the image capturing device is mounted on the main body of the apparatus.