CN215264202U

CN215264202U - Optical imaging system, imaging module and electronic equipment

Info

Publication number: CN215264202U
Application number: CN202121188321.0U
Authority: CN
Inventors: 乐宇明; 董勇兵; 赵迪; 其他发明人请求不公开姓名
Original assignee: Tianjin OFilm Opto Electronics Co Ltd
Current assignee: Jiangxi Oufei Optics Co ltd
Priority date: 2021-05-28
Filing date: 2021-05-28
Publication date: 2021-12-21
Anticipated expiration: 2031-05-28

Abstract

The utility model discloses an optical imaging system, formation of image module and electronic equipment, optical imaging system includes by thing side to picture side along the optical axis: the lens comprises a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element, wherein the first lens element has negative refractive power; the second lens element with negative refractive power; the third lens element with positive refractive power; the fourth lens element with positive refractive power; the fifth lens element with positive refractive power; the sixth lens element with negative refractive power; the seventh lens element with positive refractive power; the optical imaging system satisfies the following conditional expression: 5.5mm < f1 f2/f <17.7 mm; wherein f1 is the focal length of the first lens; f2 is the focal length of the second lens; f is the effective focal length of the optical imaging system. According to the utility model discloses an optical imaging system, through the collocation of a plurality of lens power of refracting and shape of face, when realizing that the lens is miniaturized, can also keep good optical property.

Description

Optical imaging system, imaging module and electronic equipment

Technical Field

The utility model belongs to the technical field of the imaging technique and specifically relates to an optical imaging system, imaging module and electronic equipment are related to.

Background

At present, the requirement to road traffic safety and car safety constantly improves along with the country, and look around the camera, ADAS and unmanned driving market's play, on-vehicle camera lens more and more be applied to in the car driver assistance system, meanwhile, people also propose higher requirement to the imaging quality of on-vehicle camera lens, the aspect such as comfort level of picture, look around the camera, through with a plurality of big wide-angle camera lenses in the reasonable distribution of automobile body, splice together the birds-eye view picture of automobile top all directions, make the driver see the image around the car clearly, can effectively avoid backing a car and roll, scrape the emergence of accidents such as bumper and wheel hub, look around the camera simultaneously and can also discern parking passageway sign, curb and near vehicle.

The existing ultra-wide-angle camera lens is difficult to simultaneously meet shooting and clear imaging in a large angle range, so that early warning is difficult to accurately make in real time, and further, the driving risk is caused.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, an object of the present invention is to provide an optical imaging system, which can capture details of a subject through a plurality of lens refractive powers and a surface shape, and can maintain good optical performance and high pixel characteristics while realizing miniaturization of the lens.

According to the utility model discloses optical imaging system of first aspect embodiment, include along the optical axis by the object side to the image side:

a first lens element with negative refractive power;

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

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

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

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

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

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

the optical imaging system satisfies the following conditional expression:

5.5mm<f1*f2/f<17.7mm；

wherein f1 is the focal length of the first lens; f2 is the focal length of the second lens; f is the effective focal length of the optical imaging system.

According to the optical imaging system of the present invention, the first lens element and the second lens element have negative refractive power, which is favorable for enlarging the field angle of the optical imaging system, the third lens element, the fourth lens element and the fifth lens element have positive refractive power, and the object side surface is convex, which is favorable for converging light, and balancing the aberration generated by the first two lens elements in the negative direction, wherein the fifth lens element has a biconvex shape, which is favorable for reducing the total length of the optical imaging system, thereby realizing miniaturization of the lens elements, the sixth lens element has negative refractive power, and the lens elements have a biconcave shape, which generates stronger negative refractive power, which balances the aberration generated by the optical system in the positive direction, the seventh lens element has positive refractive power, and the convex image side surface can suppress the angle of the off-axis light emitted from the image side surface of the seventh lens element, thereby easily ensuring that the light is incident on the image surface, the generation of the dark corner is prevented. Through the matching of the refractive power and the surface shape of the plurality of lenses, the details of a shot object can be well captured, and the good optical performance and the high pixel characteristics can be kept while the miniaturization of the lenses is realized. In addition, the optical system meets the conditional expression of 5.5mm < f1 f2/f <17.7mm, and the overall refractive power is adjusted by reasonably distributing the focal lengths of the first lens and the second lens, so that the field angle range of the optical imaging system is expanded, and the imaging quality is improved. When the refractive power of the first lens element and the refractive power of the second lens element exceed the upper limit of the relational expression, large-angle light rays are difficult to enter the optical imaging system, and the field angle range of the optical imaging system is not easy to expand; when the refractive power of the first lens element and the second lens element is too high, the first lens element and the second lens element are prone to generate strong astigmatism and chromatic aberration, which is not favorable for high-resolution imaging characteristics.

According to the utility model discloses an optical imaging system, optical imaging system satisfies following conditional expression:

31<Vd5-Vd6<61；

vd5 is the d-light dispersion coefficient of the fifth lens; vd6 is the d-light dispersion coefficient of the sixth lens, so that the optical imaging system has good imaging quality and reduces chromatic aberration through reasonable matching of materials.

2<f4/f<5；

the f4 is a focal length of the fourth lens element, and specifically, the fourth lens element provides positive refractive power for the optical imaging system, corrects chromatic aberration, reduces decentering sensitivity, facilitates correction of system aberration, and improves imaging resolution. Exceeding the range of the relation is not favorable for correcting the aberration of the optical imaging system, thereby reducing the imaging quality.

4.6<TTL/f<13.6；

wherein, TTL is a distance on the optical axis from the object-side surface of the first lens element to the image plane. Specifically, by defining the relationship between the total optical length of the optical imaging system and the focal length of the optical imaging system, the total optical length of the optical imaging system is controlled while the field angle range of the optical imaging system is satisfied, and the characteristic of miniaturization of the optical imaging system is satisfied. The optical imaging system is too long in total length to be beneficial to miniaturization due to the fact that the upper limit of the relational expression is exceeded; if the optical imaging system has an excessively long focal length exceeding the lower limit of the conditional expression, it is not favorable to satisfy the field angle range of the optical imaging system, and sufficient object space information cannot be obtained.

-2.1<f123/f<-1.1；

the f123 is a combined focal length of the first lens, the second lens and the third lens, and specifically, the first lens, the second lens and the third lens provide negative refractive power for the system as a whole, so that a large-angle light beam can penetrate through and enter the diaphragm, the wide-angle of the optical imaging system is realized, and the brightness of the image plane of the large-angle field of view is improved. When the upper limit of the conditional expression is exceeded, the bending force of the front lens group is too strong, and serious astigmatism is easily generated in a large-angle edge view field, so that edge resolution is reduced; if the lower limit of the conditional expression is exceeded, the bending force of the front lens group is insufficient, which is not favorable for the wide angle of the optical imaging system.

1.2<f567/f<5.2；

f567 is a combined focal length of the fifth lens element, the sixth lens element and the seventh lens element, specifically, a positive refractive power is provided for the system by the combined focal length of the fifth lens element, the sixth lens element and the seventh lens element, and the height of the incident light ray of the light beam exiting the optical imaging system is favorably controlled by satisfying the relation, so as to reduce the high-order aberration of the optical imaging system and the size of the outer diameter of the lens element; on the other hand, the influence of the curvature of field generated by the front lens group on the resolving power can be corrected.

3.8<Imgh/epd<4.8；

wherein Imgh is half of the image height corresponding to the maximum field angle of the optical imaging system, epd is the entrance pupil diameter of the optical imaging system, and specifically, if the entrance pupil diameter exceeds the upper limit of the conditional expression, the entrance pupil diameter of the optical imaging system is smaller, the width of a light beam incident into the optical imaging system is reduced, which is not beneficial to the improvement of image plane brightness; and when the lower limit of the relational expression is exceeded, the image surface area of the optical imaging system is smaller, and the field range of the optical imaging system is narrowed.

-12<CT4/Sags8<-3；

wherein CT4 is the thickness of the fourth lens on the optical axis; the Sags8 is a distance from the maximum clear aperture of the image-side surface of the fourth lens to the intersection point of the image-side surface of the fourth lens and the optical axis in the optical axis direction, specifically, if the distance exceeds the conditional upper limit, the entrance pupil diameter of the optical imaging system is smaller, the width of a light beam incident into the optical imaging system is reduced, and the improvement of the image surface brightness is not facilitated; and when the lower limit of the relational expression is exceeded, the image surface area of the optical imaging system is smaller, and the field range of the optical imaging system is narrowed.

3.8<Rs3/Rs4<12.8；

wherein Rs3 is the radius of curvature of the object-side surface of the second lens on the optical axis; rs4 is the curvature radius of the image-side surface of the second lens element on the optical axis, so that the generation probability of the ghost image is reduced and the intensity of the ghost image is reduced by controlling the curvature radius of the object-side surface of the second lens element; meanwhile, the second lens is too bent, so that the processing difficulty of the lens is increased, and the problems of glass breakage and the like easily occur in the aspheric surface process forming process.

The utility model provides an imaging module, including above-mentioned optical imaging system and electron photosensitive element, wherein electron photosensitive element locates optical imaging system's image side. By installing the optical imaging system in the imaging module, the imaging module can keep good optical performance and high pixel characteristics while realizing miniaturization.

The utility model discloses still provide an electronic equipment, including above-mentioned imaging module and casing, wherein imaging module locates in the casing. By arranging the imaging module in the electronic equipment, the electronic equipment can keep good optical performance and high pixel characteristics while realizing miniaturization.

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

Drawings

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

fig. 1 is a schematic structural diagram of embodiment 1 of an optical imaging system according to an embodiment of the present invention;

fig. 2 is a spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%)' in embodiment 1 of the optical imaging system according to an embodiment of the present invention;

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

fig. 4 is a spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%)' in embodiment 2 of the optical imaging system according to an embodiment of the present invention;

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

fig. 6 is a spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) -in embodiment 3 of the optical imaging system according to an embodiment of the present invention;

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

fig. 8 is a spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) -in embodiment 4 of the optical imaging system according to an embodiment of the present invention;

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

fig. 10 is a spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) -in embodiment 5 of the optical imaging system according to an embodiment of the present invention;

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

fig. 12 is a spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion diagram (%) in embodiment 6 of the optical imaging system according to an embodiment of the present invention.

Detailed Description

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

In the description of the present invention, it is to be understood that the features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Referring to fig. 1-12, an optical imaging system 100 according to an embodiment of the present invention is described, wherein the optical imaging system 100 can be disposed on an imaging module, so that an object can be imaged in the imaging module through the optical imaging system 100.

As shown in fig. 1, fig. 3, fig. 5, fig. 7, fig. 9, and fig. 11, an optical imaging system 100 according to an embodiment of the present invention includes, from an object side to an image side along an optical axis: a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7.

Specifically, the first lens element L1 has negative refractive power; the second lens element L2 with negative refractive power has a convex object-side surface S3 at a paraxial region and a concave image-side surface S4 at a paraxial region of the second lens element L2; the third lens element L3 with positive refractive power has a convex object-side surface S5 at paraxial region of the third lens element L3; the fourth lens element L4 with positive refractive power has a convex object-side surface S7 at paraxial region of the fourth lens element L4; the fifth lens element L5 with positive refractive power has a convex object-side surface S9 at a paraxial region and a convex image-side surface S10 at a paraxial region of the fifth lens element L5; the sixth lens element L6 with negative refractive power has a concave object-side surface S11 at a paraxial region and a concave image-side surface S12 at a paraxial region of the sixth lens element L6; the seventh lens element L7 with positive refractive power has a convex object-side surface S13 at a paraxial region and a convex image-side surface S14 at a paraxial region of the seventh lens element L7.

Further, the optical imaging system 100 satisfies the following conditional expression: 5.5mm < f1 f2/f <17.7 mm; wherein f1 is the focal length of the first lens L1; f2 is the focal length of the second lens L2; f is the effective focal length of the optical imaging system 100. If the refractive powers of the first lens element L1 and the second lens element L2 are insufficient, large-angle light is difficult to enter the optical imaging system 100, which is not favorable for expanding the field angle range of the optical imaging system 100; if the refractive power of the first lens element L1 and the refractive power of the second lens element L2 are too strong, strong astigmatism and chromatic aberration are likely to occur, which is not favorable for high-resolution imaging characteristics.

For example, as shown in fig. 1, in a direction from the object side surface to the image side surface, two side surfaces of the first lens L1 are respectively expressed as: according to the utility model discloses an optical imaging system 100, through the collocation of a plurality of lens power of refracting and shape of face, the details of the seizure object of taking a photograph that can be fine when realizing that the lens is miniaturized, can also keep good optical property and high pixel characteristic.

According to the present invention, the optical imaging system 100 of an embodiment of the present invention satisfies the following conditional expressions: 31< Vd5-Vd6< 61; vd5 is the d-color dispersion coefficient of the fifth lens L5; vd6 is the d-dispersion coefficient of the sixth lens L6. Thus, the optical imaging system 100 has good imaging quality and reduced chromatic aberration through reasonable matching of materials.

According to the present invention, the optical imaging system 100 of an embodiment of the present invention satisfies the following conditional expressions: 2< f4/f < 5; wherein f4 is the focal length of the fourth lens L4; f is the effective focal length of the optical imaging system 100. Specifically, the fourth lens element L4 provides positive refractive power for the optical imaging system 100, corrects chromatic aberration, reduces decentration sensitivity, facilitates correction of system aberration, and improves imaging resolution. Exceeding the range of the relationship is not favorable for correcting the aberration of the optical imaging system 100, thereby reducing the imaging quality.

According to the present invention, the optical imaging system 100 of an embodiment of the present invention satisfies the following conditional expressions: 4.6< TTL/f < 13.6; wherein TTL is an axial distance from the object-side surface S1 of the first lens element L1 to the image plane S19; f is the effective focal length of the optical imaging system 100. Specifically, by defining the relationship between the total optical length of the optical imaging system 100 and the focal length of the optical imaging system 100, the total optical length of the optical imaging system 100 is controlled while satisfying the field angle range of the optical imaging system 100, which satisfies the feature of miniaturization of the optical imaging system 100. Exceeding the upper limit of the relational expression, the total length of the optical imaging system 100 is too long, which is not beneficial to miniaturization; if the optical imaging system 100 has an excessively long focal length exceeding the lower limit of the conditional expression, it is not favorable to satisfy the field angle range of the optical imaging system 100, and sufficient object space information cannot be obtained.

According to the present invention, the optical imaging system 100 of an embodiment of the present invention satisfies the following conditional expressions: -2.1< f123/f < -1.1; wherein f123 is a combined focal length of the first lens L1, the second lens L2, and the third lens L3; f is the effective focal length of the optical imaging system 100. Specifically, the first lens element L1, the second lens element L2, and the third lens element L3 provide negative refractive power for the system as a whole, which is beneficial for the large-angle light beam to penetrate through and enter the stop STO, thereby realizing the wide-angle of the optical imaging system 100 and ensuring the improvement of the image surface brightness in the large-angle field. When the upper limit of the conditional expression is exceeded, the bending force of the front lens group is too strong, and serious astigmatism is easily generated in a large-angle edge view field, so that edge resolution is reduced; if the lower limit of the conditional expression is exceeded, the front lens group bending force is insufficient, which is disadvantageous for the wide angle of the optical imaging system 100.

According to the present invention, the optical imaging system 100 of an embodiment of the present invention satisfies the following conditional expressions: 1.2< f567/f < 5.2; wherein f567 is a combined focal length of the fifth lens L5, the sixth lens L6, and the seventh lens L7; f is the effective focal length of the optical imaging system 100. Specifically, positive refractive power is provided for the system through the combined focal length of the fifth lens element L5, the sixth lens element L6 and the seventh lens element L7, and the height of the incident light ray of the light ray bundle exiting the optical imaging system 100 is favorably controlled by satisfying the relation formula on the one hand, so as to reduce the high-level aberration of the optical imaging system 100 and the size of the outer diameter of the lens; on the other hand, the influence of the curvature of field generated by the front lens group on the resolving power can be corrected.

According to the present invention, the optical imaging system 100 of an embodiment of the present invention satisfies the following conditional expressions: 3.8< Imgh/epd < 4.8; where Imgh is half the image height corresponding to the maximum field angle of the optical imaging system 100, and epd is the entrance pupil diameter of the optical imaging system 100. Specifically, if the upper limit of the conditional expression is exceeded, the diameter of the entrance pupil of the optical imaging system 100 is small, the width of a beam of light entering the optical imaging system 100 is reduced, and the improvement of the image plane brightness is not facilitated; when the lower limit of the relational expression is exceeded, the image plane area of the optical imaging system 100 is smaller, and the field range of the optical imaging system 100 is narrowed.

According to the present invention, the optical imaging system 100 of an embodiment of the present invention satisfies the following conditional expressions: -12< CT4/Sags8< -3; wherein, CT4 is the thickness of the fourth lens L4 on the optical axis; sags8 is the distance in the optical axis direction from the maximum clear aperture on the image side surface of the fourth lens L4 to the intersection point of the optical axis and the side surface of the fourth transparent mirror image L4. Specifically, by controlling the ratio of the thickness of the fourth lens L4 to the image-side rise value of the fourth lens L4, the problem that the thickness of the fourth lens L4 is too large or the object-side surface is too curved while the bending force is satisfied, so that the difficulty in manufacturing the lens is increased is avoided, and the reduction of the production cost is realized. Beyond the range of the conditional expression, the image side surface of the fourth lens L4 is too curved, the processing difficulty of the lens is increased, and the production cost of the lens is increased; meanwhile, the surface is too curved, which is prone to generate edge aberration, and is not favorable for improving the image quality of the optical imaging system 100.

According to the present invention, the optical imaging system 100 of an embodiment of the present invention satisfies the following conditional expressions: 3.8< Rs3/Rs4< 12.8; rs3 is the radius of curvature of the object-side surface of the second lens L2 on the optical axis; rs4 is the radius of curvature of the image-side surface of the second lens L2 on the optical axis. Thus, the curvature radius of the object side of the second lens L2 is controlled, so that the generation probability of the ghost is favorably reduced, and the intensity of the ghost is reduced; meanwhile, the second lens L2 is too bent, so that the processing difficulty of the lens is increased, and the problems of glass breakage and the like easily occur in the aspheric surface process forming process.

According to the utility model discloses an optical imaging system 100 still includes: the stop STO, specifically, the stop STO may be disposed between the lens and the lens, so that the intensity of the light in the optical imaging system 100 may be adjusted according to actual requirements by disposing the stop STO between the lens and the lens.

In some embodiments, at least one lens of the optical imaging system 100 has an aspheric surface, which is called aspheric when at least one side surface (object side surface or image side surface) of the lens is aspheric. In one embodiment, both the object-side surface and the image-side surface of each lens can be designed to be aspheric. The aspheric design can help the optical imaging system 100 to eliminate aberration more effectively, and improve imaging quality. In some embodiments, at least one lens of the optical imaging system 100 may have a spherical surface shape, and the design of the spherical surface shape may reduce the difficulty and cost of manufacturing the lens. In some embodiments, in order to consider the manufacturing cost, the manufacturing difficulty, the imaging quality, the assembly difficulty, and the like, the design of each lens surface in the optical imaging system 100 may be configured by aspheric and spherical surface types. It should be noted that when the object-side or image-side surface of a lens is aspheric, there can be inflection structures in the surface, where the type of surface from center to edge changes, such as a convex surface near the optical axis and a concave surface near the maximum effective aperture.

The surface shape of the aspheric surface can be calculated by referring to an aspheric surface formula:

z is the distance from a corresponding point on the aspheric surface to a tangent plane of the surface at the optical axis, r is the distance from the corresponding point on the aspheric surface to the optical axis, c is the curvature of the aspheric surface at the optical axis, k is a conical coefficient, and Ai is a high-order term coefficient corresponding to the ith-order high-order term in the aspheric surface type formula.

On the other hand, in some embodiments, the material of at least one lens in the optical imaging system 100 is Plastic (Plastic), and the Plastic material may be polycarbonate, gum, or the like. In some embodiments, at least one lens of the optical imaging system 100 is made of Glass (Glass). The lens made of plastic can reduce the production cost of the optical imaging system 100, and the lens made of glass can endure higher or lower temperature and has excellent optical effect and better stability. In some embodiments, lenses of different materials may be disposed in the optical imaging system 100, that is, a design combining a glass lens and a plastic lens may be adopted, but the specific configuration relationship may be determined according to practical requirements, and is not exhaustive here.

In summary, according to the present invention, the optical imaging system 100 can capture the details of the object through the arrangement of the refractive power and the surface shape of the plurality of lenses, and can maintain good optical performance and high pixel characteristics while realizing the miniaturization of the lenses.

The present invention will be described in detail with reference to the following embodiments and accompanying drawings.

Example 1

Referring to fig. 1-2, the optical imaging system of the present embodiment satisfies the conditions of table 1 and table 2 below, wherein the reference wavelength of the focal length is 546.07nm, the reference wavelength of the refractive index and the abbe number is 587.56nm, and the units of the Y radius, the thickness and the focal length are millimeters (mm).

TABLE 1

Where f is the effective focal length of the optical imaging system 100, FNO is the f-number of the optical imaging system 100, and FOV is the maximum field angle of the optical imaging system 100.

In table 1, the first lens element L1 with negative refractive power has a convex object-side surface S1 of the first lens element L1 at a paraxial region, a concave image-side surface S2 of the first lens element L1 at a paraxial region, and two spherical surfaces of the first lens element L1.

Further, the second lens element L2 with negative refractive power has a convex object-side surface S3 of the second lens element L2 at a paraxial region, a concave image-side surface S4 of the second lens element L2 at a paraxial region, and both surfaces of the second lens element L2 are aspheric.

Further, the third lens element L3 with positive refractive power has a convex object-side surface S5 of the third lens element L3 at a paraxial region, a concave image-side surface S6 of the third lens element L3 at a paraxial region, and both surfaces of the third lens element L3 are aspheric.

Further, the fourth lens element L4 with positive refractive power has a concave object-side surface S7 of the fourth lens element L4 at a paraxial region, a convex image-side surface S8 of the fourth lens element L4 at a paraxial region, and both surfaces of the fourth lens element L4 are spherical.

Further, the fifth lens element L5 with positive refractive power has a convex object-side surface S9 of the fifth lens element L5 at a paraxial region, a convex image-side surface S10 of the fifth lens element L5 at a paraxial region, and both surfaces of the fifth lens element L5 are spherical.

Further, the sixth lens element L6 with negative refractive power has a concave object-side surface S11 of the sixth lens element L6 at a paraxial region, a concave image-side surface S12 of the sixth lens element L6 at a paraxial region, and both surfaces of the sixth lens element L6 are aspheric.

Further, the seventh lens element L7 with positive refractive power has a convex object-side surface S13 of the seventh lens element L7 at a paraxial region, a convex image-side surface S14 of the seventh lens element L7 at a paraxial region, and both surfaces of the seventh lens element L7 are aspheric.

Table 2 below is the aspherical high-order coefficient a4, a6, A8, a10, a12, a14, a16, a18, a20 of the aspherical lens:

TABLE 2

Number of noodles	S3	S4	S5	S6
					K	-7.322E+00	-3.116E-01	-7.224E-01	9.830E+00
A4	6.348E-02	-8.343E-02	-1.192E-02	3.837E-02
					A6	-1.814E-03	4.035E-02	9.095E-02	6.008E-03
A8	3.134E-04	-7.056E-02	-8.973E-01	-1.604E-04
					A10	-8.528E-05	8.344E-03	2.159E-03	-7.399E-04
A12	6.729E-06	-7.815E-04	-8.794E-04	2.592E-05
					A14	0.000E+00	0.000E+00	0.000E+00	0.000E+00
A16	0.000E+00	0.000E+00	0.000E+00	0.000E+00
					A18	0.000E+00	0.000E+00	0.000E+00	0.000E+00
A20	0.000E+00	0.000E+00	0.000E+00	0.000E+00
					Number of noodles	S11	S12	S13	S14
K	1.237E+00	-5.841E+00	-5.920E+00	-9.759E-01
					A4	-4.132E+00	-4.290E-03	8.912E-03	9.328E-02
A6	6.758E-02	3.862E-03	2.055E-03	-7.188E-01
					A8	-6.093E-02	-8.483E-04	-6.293E-03	6.535E-03
A10	9.372E-03	8.533E-04	6.190E-04	-4.599E-04
					A12	-3.016E-03	-2.690E-05	-8.285E-04	3.860E-05
A14	0.000E+00	0.000E+00	0.000E+00	0.000E+00
					A16	0.000E+00	0.000E+00	0.000E+00	0.000E+00
A18	0.000E+00	0.000E+00	0.000E+00	0.000E+00
					A20	0.000E+00	0.000E+00	0.000E+00	0.000E+00

Fig. 2(a) is a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of example 1, which shows the convergent focus deviation of light rays of different wavelengths after passing through the optical imaging system 100. The ordinate of the figure represents Normalized Pupil coordinates (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa of the figure represents the distance (in mm) from the imaging plane S19 to the intersection of the light ray and the optical axis. The wavelengths of light rays used in fig. 2(a) are 435.840nm, 486.130nm, 546.07nm, 587.560nm, and 656.270nm, respectively, and the focus offset amounts of the five light rays after being condensed by the optical imaging system 100 are in the range of-0.05 mm to 0.05 mm. As can be seen from the longitudinal spherical aberration diagram of example 1, the convergent focus deviation degrees of the light rays of the respective wavelengths in example 1 tend to be uniform, and the diffuse speckles or color halos in the imaging picture are effectively suppressed.

Fig. 2 (b) is a Field curvature diagram (volumetric Field Curves) of the optical imaging system 100 according to example 1, wherein the S-curve represents sagittal Field curvature at 546.07nm, and the T-curve represents meridional Field curvature at 546.07 nm. After passing through the optical imaging system 100, the light with a wavelength of 546.07nm has sagittal field curvature and tangential field curvature with a focus offset in a range of-0.1 mm to 0.1 mm. As can be seen from fig. 2 (b), the field curvature of the optical imaging system 100 of example 1 is small, the field curvature and astigmatism of each field (especially, the peripheral field) are well corrected, and the center and the periphery of the field have sharp images.

Fig. 2(c) shows a Distortion diagram (Distortion) of the optical imaging system 100 of embodiment 1, in which the Distortion ratio of the light with a wavelength of 546.07nm after passing through the optical imaging system 100 is in the range of-100.0% to 100.0%. As can be seen from fig. 2(c), the image distortion caused by the main beam is small, and the imaging quality of the optical imaging system 100 is excellent.

In summary, fig. 2(a) - (c) show that the optical imaging system 100 of example 1 has small aberration and excellent imaging quality.

Example 2

Referring to fig. 3 to 4, the optical imaging system of the present embodiment satisfies the conditions of table 3 and table 4 below, wherein the reference wavelength of the focal length is 546.07nm, the reference wavelength of the refractive index and the abbe number is 587.56nm, and the units of the Y radius, the thickness, and the focal length are millimeters (mm).

TABLE 3

In table 3, the first lens element L1 with negative refractive power has a convex object-side surface S1 of the first lens element L1 at a paraxial region, a concave image-side surface S2 of the first lens element L1 at a paraxial region, and two spherical surfaces of the first lens element L1.

Table 4 below is the aspherical high-order coefficient a4, a6, A8, a10, a12, a14, a16, a18, a20 of the aspherical lens:

TABLE 4

Fig. 4(a) -4 (c) show the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the second embodiment. Wherein the reference wavelength of the light rays of the astigmatism curve and the distortion curve is 546.07 nm. As can be seen from fig. 4 (b), the optical imaging system 100 according to the second embodiment can achieve good imaging quality.

Example 3

Referring to fig. 5-6, the optical imaging system 100 of the present embodiment satisfies the conditions of table 5 and table 6, wherein the reference wavelength of the focal length is 546.07nm, the reference wavelength of the refractive index and the abbe number is 587.56nm, and the units of the Y radius, the thickness and the focal length are millimeters (mm).

TABLE 5

In table 5, the first lens element L1 with negative refractive power has a convex object-side surface S1 of the first lens element L1 at a paraxial region, a concave image-side surface S2 of the first lens element L1 at a paraxial region, and two spherical surfaces of the first lens element L1.

Further, the third lens element L3 with positive refractive power has a convex object-side surface S5 at a paraxial region of the third lens element L3, a convex image-side surface S6 at a paraxial region of the third lens element L3, and both surfaces of the third lens element L3 are aspheric.

Further, the fifth lens element L5 with positive refractive power has a convex object-side surface S9 at a paraxial region of the fifth lens element L5, a convex image-side surface S10 at a paraxial region of the fifth lens element L5, and both surfaces of the fifth lens element L5 are aspheric.

Table 6 below is the aspherical high-order coefficient a4, a6, A8, a10, a12, a14, a16, a18, a20 of the aspherical lens:

TABLE 6

Fig. 6(a) -6 (c) show the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical system of the third embodiment. Wherein the reference wavelength of the light rays of the astigmatism curve and the distortion curve is 546.07 nm. As can be seen from fig. 6 (b), the optical imaging system 100 according to the third embodiment can achieve good imaging quality.

Example 4

Referring to fig. 7-8, the optical imaging system 100 of the present embodiment satisfies the conditions of table 7 and table 8, wherein the reference wavelength of the focal length is 546.07nm, the reference wavelength of the refractive index and the abbe number is 587.56nm, and the units of the Y radius, the thickness and the focal length are millimeters (mm).

TABLE 7

In table 7, the first lens element L1 with negative refractive power has a convex object-side surface S1 of the first lens element L1 at a paraxial region, a concave image-side surface S2 of the first lens element L1 at a paraxial region, and two spherical surfaces of the first lens element L1.

Further, the fourth lens element L4 with positive refractive power has a convex object-side surface S7 of the fourth lens element L4 at a paraxial region, a convex image-side surface S8 of the fourth lens element L4 at a paraxial region, and both surfaces of the fourth lens element L4 are spherical.

Further, the fifth lens element L5 with positive refractive power has a convex object-side surface S9 at a paraxial region of the fifth lens element L5, a convex image-side surface S10 at a paraxial region of the fifth lens element L5, and an aspheric object-side surface S9 of the fifth lens element L5.

Table 8 below is the aspherical high-order coefficient a4, a6, A8, a10, a12, a14, a16, a18, a20 of the aspherical lens:

TABLE 8

Fig. 8(a) -8 (c) show a longitudinal spherical aberration curve, an astigmatism curve, and a distortion curve of the optical system of the fourth embodiment. Wherein the reference wavelength of the light rays of the astigmatism curve and the distortion curve is 546.07 nm. As can be seen from fig. 8 (b), the optical imaging system 100 according to the fourth embodiment can achieve good imaging quality.

Example 5

Referring to fig. 9-10, the optical imaging system 100 of the present embodiment satisfies the conditions of table 9 and table 10 below, wherein the reference wavelength of the focal length is 546.07nm, the reference wavelength of the refractive index and the abbe number is 587.56nm, and the units of the Y radius, the thickness and the focal length are millimeters (mm).

TABLE 9

In table 9, the first lens element L1 with negative refractive power has a convex object-side surface S1 of the first lens element L1 at a paraxial region, a concave image-side surface S2 of the first lens element L1 at a paraxial region, and two spherical surfaces of the first lens element L1.

Table 10 below is the aspherical high-order coefficient a4, a6, A8, a10, a12, a14, a16, a18, a20 of the aspherical lens:

watch 10

Fig. 10(a) -10 (c) show a longitudinal spherical aberration curve, an astigmatism curve, and a distortion curve of the optical system of the fifth embodiment. Wherein the reference wavelength of the light rays of the astigmatism curve and the distortion curve is 546.07 nm. As can be seen from fig. 10 (b), the optical imaging system 100 according to the fifth embodiment can achieve good imaging quality.

Example 6

Referring to fig. 11-12, the optical imaging system 100 of the present embodiment satisfies the conditions of tables 11 and 12, wherein the reference wavelength of the focal length is 546.07nm, the reference wavelength of the refractive index and the abbe number is 587.56nm, and the units of the Y radius, the thickness and the focal length are millimeters (mm).

TABLE 11

In table 11, the first lens element L1 with negative refractive power has a convex object-side surface S1 of the first lens element L1 at a paraxial region, a concave image-side surface S2 of the first lens element L1 at a paraxial region, and two spherical surfaces of the first lens element L1.

Table 12 below is the aspherical high-order coefficient a4, a6, A8, a10, a12, a14, a16, a18, a20 of the aspherical lens:

TABLE 12

Fig. 12(a) -12 (c) show a longitudinal spherical aberration curve, an astigmatism curve, and a distortion curve of the optical system of the fourth embodiment. Wherein the reference wavelength of the light rays of the astigmatism curve and the distortion curve is 546.07 nm. As can be seen from fig. 12 (b), the optical imaging system 100 according to the sixth embodiment can achieve good imaging quality. Referring to table 13, table 13 shows values of f1 × f2/f, Vd5-Vd6, f4/f, f4/f, f123/f, f567/f, Imgh/epd, CT4/Sags8, and Rs3/Rs4 in the first to sixth embodiments of the present invention.

Watch 13

	First embodiment	Second embodiment	Third embodiment	Fourth embodiment	Fifth embodiment	Sixth embodiment
							f1*f2/f	8.057	5.561	5.691	14.789	17.499	17.672
Vd5-Vd6	40.712	40.712	32.481	60.000	60.734	32.481
							f4/f	3.341	4.332	4.690	2.335	2.427	3.438
f4/f	7.317	6.341	4.970	12.031	12.405	13.514
							f123/f	-1.794	-1.676	-2.002	-1.554	-1.453	-1.584
f567/f	1.560	1.410	1.232	5.100	3.621	3.948
							Imgh/epd	4.342	4.578	4.723	3.917	4.127	4.127
CT4/Sags8	-11.978	-6.164	-4.316	-3.152	-3.496	-3.064
							Rs3/Rs4	11.028	8.762	12.724	3.964	6.301	5.556

As can be seen from table 13, the optical imaging systems 100 in the first to sixth embodiments each satisfy the following condition: 5.5< f1 f2/f < 17.7; 31< Vd5-Vd6< 61; 2< f4/f < 5; 4.6< TTL/f < 13.6; -2.1< f123/f < -1.1; 1.2< f567/f < 5.2; 3.8< Imgh/epd < 4.8; -12< CT4/Sags8< -3; 3.8< Rs3/Rs4< 12.8.

The utility model discloses provide an imaging module of optical imaging system 100 who has above-mentioned embodiment again.

According to the utility model discloses imaging module of second aspect embodiment includes: the imaging optical system 100 and the electronic photosensitive element, the electronic photosensitive element is set up in the image side of the imaging optical system 100. Thus, by providing the electron photosensitive element on the image side of the optical imaging system 100, the light entering the imaging system can be imaged on the electron photosensitive element.

According to the utility model discloses imaging module is through locating imaging module with optical imaging system 100 on for imaging module can satisfy micro-design, can also make imaging module's field of view scope great, thereby makes imaging module's practicality high.

The utility model discloses still provide an electronic equipment of the imaging module of having above-mentioned embodiment.

According to the utility model discloses electronic equipment of third aspect embodiment includes: the imaging module is arranged in the shell, and at least part of the imaging module protrudes out of the shell to obtain an image.

From this, through locating the formation of image module in the casing after for the casing can protect the formation of image module, thereby makes the formation of image module can make a video recording steadily. In addition, at least part of the imaging module protrudes out of the shell, so that the imaging module can better acquire images, and the imaging quality is high. It is understood that the electronic device may be a mobile phone, an ipad, a tablet computer, and the like, which is not limited herein.

According to the utility model discloses electronic equipment is through locating the imaging module in the electronic equipment for electronic equipment uses the photo that the imaging module was shot or the quality of making a video recording is high-quality, and the imaging module is located the electronic equipment that the volume is less, thickness is thinner back moreover, can not influence electronic equipment's whole molding.

Other configurations and operations of the optical imaging system 100, the imaging module and the electronic device according to the embodiments of the present invention are known to those skilled in the art and will not be described in detail herein.

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

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

Claims

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

a first lens element with negative refractive power;

the optical imaging system satisfies the following conditional expression:

5.5mm<f1*f2/f<17.7mm；

2. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression:

31<Vd5-Vd6<61；

vd5 is the d-light dispersion coefficient of the fifth lens; vd6 is the d-light dispersion coefficient of the sixth lens.

3. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression:

2<f4/f<5；

wherein f4 is the focal length of the fourth lens.

4. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression:

4.6<TTL/f<13.6；

wherein, TTL is a distance on the optical axis from the object-side surface of the first lens element to the image plane.

5. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression:

-2.1<f123/f<-1.1；

wherein f123 is a combined focal length of the first lens, the second lens, and the third lens.

6. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression:

1.2<f567/f<5.2；

wherein f567 is a combined focal length of the fifth lens, the sixth lens, and the seventh lens.

7. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression:

3.8<Imgh/epd<4.8；

where Imgh is half of the image height corresponding to the maximum field angle of the optical imaging system, and epd is the entrance pupil diameter of the optical imaging system.

8. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression:

-12<CT4/Sags8<-3；

wherein CT4 is the thickness of the fourth lens on the optical axis; the Sags8 is the distance from the maximum clear aperture position of the image side surface of the fourth lens to the intersection point of the image side surface of the fourth lens and the optical axis in the optical axis direction.

9. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression:

3.8<Rs3/Rs4<12.8；

wherein Rs3 is the radius of curvature of the object-side surface of the second lens on the optical axis; rs4 is the radius of curvature of the image side surface of the second lens on the optical axis.

10. An imaging module, comprising:

an optical imaging system according to any one of claims 1-9;

and the electronic photosensitive element is arranged on the image side of the optical imaging system.

11. An electronic device, characterized in that the electronic device comprises: the imaging module of claim 10, and a housing within which the imaging module is disposed.