CN112859288B

CN112859288B - Optical imaging system, image capturing device and electronic equipment

Info

Publication number: CN112859288B
Application number: CN201911186766.2A
Authority: CN
Inventors: 蔡雄宇; 兰宾利; 周芮
Original assignee: Jiangxi Oufei Optics Co ltd
Current assignee: Jiangxi Oufei Optics Co ltd
Priority date: 2019-11-27
Filing date: 2019-11-27
Publication date: 2024-06-18
Anticipated expiration: 2039-11-27
Also published as: CN112859288A

Abstract

The invention provides an optical imaging system, which sequentially comprises a first lens group with positive focal power from an object side to an image side; a second lens group having positive optical power; and a third lens group having negative optical power; the first lens group comprises a first lens, wherein the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a convex surface or a plane; the second lens group comprises two lenses; the third lens group includes two lenses. The optical imaging system has high pixel resolution and small volume. In addition, 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 invention relates to optical imaging technology, and in particular, to an optical imaging system, an image capturing device, and an electronic apparatus.

Background

With the popularization of automobiles, traffic accidents caused by factors such as fatigue driving frequently occur. Nowadays, the vehicle-mounted industry rapidly develops, and technologies of vehicle-mounted driving such as ADAS (ADVANCED DRIVING ASSISTANT SYSTEM, advanced driving assistance system), DMS (Driver Monitor System, driving early warning system) and the like are also mature gradually, and the development of the vehicle-mounted technologies is not separated from the imaging technology. However, the existing imaging device meeting the vehicle-mounted miniaturization requirement is low in resolution, the state of a driver cannot be well monitored, and whether the driver performs fatigue driving or not is judged according to the related information such as the eye state, the eye closing times, the eye closing amplitude, the yawning, the face state and the like, so that early warning is provided, and the driving safety is improved.

Disclosure of Invention

In view of this, the present invention provides an optical imaging system having a high pixel resolution.

It is also necessary to provide an imaging device using the above optical imaging system.

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

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

a first lens group having positive optical power;

A second lens group having positive optical power; and

A third lens group having negative optical power;

The first lens group comprises a first lens, wherein the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a convex surface or a plane; the object side surface of the first lens is a convex surface, so that positive focal power of the first lens which bears the main imaging function of the optical imaging system can be enhanced, and ultrathin effect is facilitated. The image side surface of the first lens is set to be a plane, so that the optical imaging system is easy to assemble and bear, the assembling sensitivity of the lens is reduced, the yield is improved, and the production cost of the lens is reduced.

The second lens group comprises two lenses; the third lens group includes two lenses.

Wherein the second lens group includes a second lens having negative optical power and a third lens having positive optical power. The second lens and the third lens provide positive focal power for the whole optical imaging system, can converge large-angle light rays to enter the system, and optimize the phase difference of large-angle view fields.

The object side surface of the second lens is a concave surface, and the image side surface is a convex surface or a concave surface; the object side surface and the image side surface of the third lens are both convex. By reasonably configuring each shape in the second lens group, the imaging field of view range can be improved, and the light beam carrying the shot object information can be effectively absorbed into the optical imaging system and transmitted to the imaging surface.

Wherein the third lens group includes a fourth lens having negative optical power and a fifth lens having optical power. By arranging the third lens group with negative focal power, the emission angle of the emission optical system is contracted, and meanwhile, the angle of light rays emitted into an imaging surface is reduced, so that the photosensitivity is improved.

The object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a concave surface or a convex surface; the object side surface of the fifth lens is a concave surface or a convex surface, and the image side surface is a concave surface, a convex surface or a plane. Through the reasonable configuration of the shape, the front lens group field region is corrected, the aberration of the optical imaging system is optimized, and the imaging resolution is improved.

When the image side surface of the fifth lens is set to be a plane, the optical imaging system is easy to assemble and bear, the assembling sensitivity of the lens is reduced, the yield is improved, and the production cost of the lens is reduced.

Wherein one lens of the first lens group, the second lens group and the third lens group is an aspheric lens. The aspherical lens is adopted, so that the aspherical lens can be easily manufactured into a shape other than a spherical surface, more control variables are obtained, aberration is reduced, and good imaging is achieved by a small number of lenses; further, the number of lenses is reduced, and miniaturization is satisfied.

Wherein an object side surface or an image side surface of one or more lenses of the first lens group, the second lens group and the third lens group is provided with an infrared transmitting film. The infrared transmission film can enable near infrared light and infrared light to pass through, cut off light of other wave bands, ensure imaging resolving power of the optical imaging system in the near infrared wave band and ensure thermal imaging quality of the optical imaging system.

The optical imaging system further comprises a diaphragm, and the effective diameter of the diaphragm is the aperture of the object side surface of the first lens. The diaphragm can enable the optical imaging system to have telecentric effect, and the efficiency of the photosensitive element for receiving images is increased.

Wherein the optical imaging system satisfies the following conditional expression:

0＜f1/f＜1；

wherein f1 is the focal length of the first lens of the optical imaging system, and f is the effective focal length of the optical imaging system.

When f1/f is more than 0 and less than 1, positive focal power can be provided for the optical imaging system, incident light beams can be focused, and the optical imaging system can effectively transfer collected image information to an imaging surface.

0＜f23/f＜3；

Wherein f23 is the focal length of the second lens group, and f is the effective focal length of the optical imaging system.

When f23/f is more than 0 and less than 3, the chromatic aberration is corrected, the decentration sensitivity is reduced, the aberration of the optical imaging system is corrected, and the imaging resolution is improved; the assembly sensitivity of the optical imaging system is reduced, the problems of lens process manufacturing and optical imaging system assembly are solved, and the yield is improved.

5＜(CT3－CT2)×100/f23＜30；

Wherein CT2 is the distance between the object side surface and the image side surface of the second lens element on the optical axis; CT3 is the distance between the object side surface and the image side surface of the third lens in the optical axis; f23 is the focal length of the second lens group.

Through reasonable configuration of the center thicknesses of the second lens and the third lens, the whole second lens group has positive focal power, aberration can be optimized, the optical imaging system is compact in structure, the total length of the optical imaging system is reduced, and miniaturization of the optical imaging system is facilitated.

1＜RS5/f＜20；

Wherein RS5 is the radius of curvature of the object side surface of the third lens, and f is the effective focal length of the optical imaging system.

When RS5/f is smaller than 1 and smaller than 20, the aberration of the optical imaging system is favorably optimized, and the generation of ghost is restrained.

4＜(RS6－RS7)/(SagS6－SagS7)＜10；

Wherein RS6 is the radius of curvature of the image side surface of the third lens element, RS7 is the radius of curvature of the object side surface of the fourth lens element, sag S6 is the sagittal height of the image side surface of the third lens element, sag S7 is the sagittal height of the object side surface of the fourth lens element.

When 4 < (RS 6-RS 7)/(SagS-SagS) < 10, the aberration of the second lens group and the aberration of the third lens group are complemented, thereby achieving the effect of correcting the aberration, and controlling the size of the optical imaging system to be more miniaturized.

－2.5＜f45/f＜－0.5；

wherein f45 is a focal length of the third lens group, and f is an effective focal length of the optical imaging system.

The third lens group has negative focal power, complements the aberration of the first lens group and the second lens group, reduces sensitivity and improves the imaging resolution of the optical imaging system.

－15＜(CT5－CT4)×100/f45＜－3；

Wherein CT4 is the distance between the object side surface and the image side surface of the fourth lens element, CT5 is the distance between the object side surface and the image side surface of the fifth lens element, and f45 is the focal length of the third lens group.

Through reasonable configuration of the center thicknesses of the fourth lens and the fifth lens, the whole third lens group has negative focal power, aberration can be optimized, the optical imaging system is compact in structure, the total length of the optical imaging system is reduced, and miniaturization is facilitated.

4＜(D23+D34)×100/TTL＜18；

wherein D23 is a distance between the image side surface of the second lens element and the object side surface of the third lens element, D34 is a distance between the image side surface of the third lens element and the object side surface of the fourth lens element, and TTL is a total length of the optical imaging system.

When 4 < (D23+D34) x 100/TTL < 18, the optical imaging system is favorable to compact structure, the total length of the optical imaging system is reduced, and the miniaturization is favorable.

0.1≤(|RS4|+|RS7|)/(|RS5|+|RS6|)＜2；

Wherein RS4 is a radius of curvature of the image side surface of the second lens element, RS5 is a radius of curvature of the object side surface of the third lens element, RS6 is a radius of curvature of the image side surface of the third lens element, and RS7 is a radius of curvature of the object side surface of the four lens elements.

When the absolute value of (|RS4|+|RS7|)/(|RS5|+|RS6|) is less than or equal to 0.1 and less than 2, the aberration of the optical imaging system is optimized, the imaging resolution is improved, and the generation of ghost is inhibited.

0.5＜Imgh/f＜1；

Wherein Imgh is the total image height of the imaging surface of the optical imaging system in the diagonal direction, and f is the effective focal length of the optical imaging system.

When 0.5 is less than Imgh/f is less than 1, the optical imaging system can have high pixels and high imaging quality, and the total length of the optical imaging system can be controlled, so that the volume of the optical imaging system is minimized.

3＜TTL/BFL＜7；

wherein BFL is the optical back focal length of the optical imaging system, and TTL is the total length of the optical imaging system.

By controlling the ratio of the optical back focus of the optical imaging system to the total length of the optical imaging system, the optical imaging system is made more compact.

2.55＜FOV/CRA＜3.55；

wherein FOV is the angular field angle of the optical imaging system and CRA is the chief ray angle of incidence of the optical imaging system.

When the FOV/CRA is more than 2.55 and less than 3.55, the optical imaging system has enough field angle to meet the requirement of high FOV of electronic products such as mobile phones, cameras, vehicles, monitoring, medical treatment and the like, and simultaneously, the angle of light rays entering the chip is reduced, and the photosensitivity is improved.

An image capturing device, comprising:

the optical imaging system described above; and

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

An electronic device, comprising:

an apparatus main body;

In the above image capturing device, the image capturing device is mounted on the apparatus main body.

Therefore, the optical imaging system of the invention is composed of three lens groups, has small volume and high pixel resolution.

Drawings

In order to more clearly illustrate the structural features and efficacy of the present invention, a detailed description thereof will be given below with reference to the accompanying drawings and examples.

Fig. 1-1 is a schematic diagram of the structure 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 an optical imaging system according to a first embodiment of the present invention, in order from left to right.

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

Fig. 2-2 is a graph of spherical aberration, astigmatism, and distortion curves of an optical imaging system according to a second embodiment of the present invention, in order 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 shows, in order from left to right, the spherical aberration, astigmatism, and distortion curves of an optical imaging system according to a third embodiment of the present invention.

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 shows, in order from left to right, the spherical aberration, astigmatism, and distortion curves of an optical imaging system according to a fourth embodiment of the present invention.

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 of spherical aberration, astigmatism, and distortion curves of an optical imaging system according to a fifth embodiment of the invention in order 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 of spherical aberration, astigmatism and distortion of an optical imaging system according to a sixth embodiment of the invention in order from left to right.

Fig. 7 is a schematic structural diagram of an image capturing device according to an embodiment of the present 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 solutions 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 will be apparent that the described embodiments are some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

Referring to fig. 1-1, 2-1, 3-1, 4-1, 5-1, and 6-1, an optical imaging system 100 according to an embodiment of the present invention is applied to a vehicle-mounted image capturing device, and includes, in order from an object side to an image side, a first lens group 10 having positive optical power, a second lens group 30 having positive optical power, and a third lens group 50 having negative optical power.

Alternatively, the first lens group 10 includes a first lens L1. The first lens L1 is made of glass and has positive optical power. The first lens element L1 includes an object-side surface S1 and an image-side surface S2. The object side surface S1 is convex, and the image side surface S2 is convex or planar. The object side surface of the first lens is a convex surface, so that positive focal power of the first lens which bears the main imaging function of the optical imaging system can be enhanced, and ultrathin effect is facilitated. The image side surface of the first lens L1 is set to be a plane, so that the optical imaging system is easy to assemble and bear, the assembling sensitivity of the lens is reduced, the yield is improved, and the production cost of the lens is reduced.

Alternatively, the second lens group 30 includes a second lens L2 having negative optical power and a third lens L3 having positive optical power. The second lens and the third lens provide positive focal power for the whole optical imaging system, can converge large-angle light rays to enter the system, and optimize the phase difference of large-angle view fields.

The second lens element L2 may be made of glass or plastic, and has an object-side surface S3 and an image-side surface S4. The object side surface S3 of the second lens element L2 is concave, and the image side surface S4 is convex or concave.

The third lens element L3 is made of 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 convex.

By reasonably configuring each shape in the second lens group, the imaging field of view range can be improved, and the light beam carrying the shot object information can be effectively absorbed into the optical imaging system and transmitted to the imaging surface.

Alternatively, the third lens group 50 includes a fourth lens L4 having negative optical power and a fifth lens L5 having optical power. By reasonably configuring each shape in the second lens group, the imaging field of view range can be improved, and the light beam carrying the shot object information can be effectively absorbed into the optical imaging system and transmitted to the imaging surface.

The fourth lens element L4 is made of glass, and has an object-side surface S7 and an image-side surface S8. The object side surface S7 is concave, and the image side surface S8 is concave or convex.

The fifth lens element L5 is made of glass, and has an object-side surface S9 and an image-side surface S10. The fifth lens L5 may have positive optical power or negative optical power. The object side surface S9 is concave or convex, and the image side surface S10 is concave, convex or planar.

Through the reasonable configuration of the shapes of the fourth lens L4 and the fifth lens L5, the front lens group field region can be corrected, the aberration of the optical imaging system can be optimized, and the imaging resolution can be improved.

When the image side surface S10 of the fifth lens element L5 is configured as a plane, the optical imaging system 100 is easy to assemble and support, and the assembling sensitivity of the lens is reduced, which is beneficial to improving the yield and reducing the production cost of the lens.

The optical imaging system 100 of the present invention is small in size, has high pixel resolution, and can be used for high-pixel imaging lenses, automatic driving, monitoring devices, etc. based on vehicle-mounted use.

In some embodiments, one lens of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 is an aspherical lens. An "aspherical lens" refers to a lens having at least one surface that is aspherical. The aspherical lens is adopted, so that the aspherical lens can be easily manufactured into a shape other than a spherical surface, more control variables are obtained, aberration is reduced, and good imaging is achieved by a small number of lenses; further, the number of lenses is reduced, and miniaturization is satisfied.

In some embodiments, one or more of the object-side and image-side surfaces of the first, second, third, fourth, and fifth lenses L1, L2, L3, L4, and L5 are provided with an infrared-transmissive film. The infrared transmission film can enable near infrared light and infrared light to pass through, cut off light of other wave bands, ensure imaging resolving power of the optical imaging system 100 in the near infrared wave band and ensure thermal imaging quality of the optical imaging system.

In some embodiments, the optical imaging system 100 further includes a diaphragm (not shown), and an effective aperture of the diaphragm is an aperture of the object-side surface S1 of the first lens L1. The diaphragm can enable the optical imaging system to have telecentric effect, and the efficiency of the photosensitive element for receiving images is increased.

In some embodiments, the optical imaging system 100 further includes a cover glass 70. The cover glass 70 has a first face 71 and a second face 72. The cover glass 70 is made of glass material and is located between the fifth lens L5 and the imaging surface 80. The cover glass 70 is used to protect the photosensitive element of the imaging surface 80 to achieve a dust-proof effect.

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

0＜f1/f＜1；

That is, f1/f may be any value between 0 and 1, for example, f1/f has a value of 0.1, 0.2, 0.3, 0.5, 0.8, 0.9, 0.99, or the like.

0＜f23/f＜3；

Wherein f23 is a focal length of the second lens group, that is, a combined focal length of the second lens L2 and the third lens L3, and f is an effective focal length of the optical imaging system.

That is, f23/f may be any number between 0 and 3, such as 0.2, 0.8, 1, 1.2, 1.5, 2, 2.5, 2.9, etc.

5＜(CT3－CT2)×100/f23＜30；

Wherein CT2 is the distance between the object side surface and the image side surface of the second lens element on the optical axis; CT3 is the distance between the object side surface and the image side surface of the third lens in the optical axis; f23 is the focal length of the second lens group, i.e., the combined focal length of the second lens L2 and the third lens L3.

That is, (CT 3-CT 2). Times.100/f 23 may be any number between 5 and 30, such as 5.1, 6, 10, 15, 20, 25, 28, 29.9, etc.

By reasonably configuring the center thicknesses of the second lens L2 and the third lens L3, the second lens group 30 has positive focal power as a whole, so that aberration can be optimized, the optical imaging system is compact in structure, the total length of the optical imaging system is reduced, and miniaturization of the optical imaging system is facilitated.

1＜RS5/f＜20；

That is, RS5/f may be any number between 1 and 20, such as 11, 2, 5, 10, 15, 18, 19.9, etc.

When RS5/f is smaller than 1 and smaller than 20, the aberration of the optical imaging system is favorably optimized, and the generation of ghost is restrained. "ghosting", also known as ghosting, refers to an additional image produced near the focal plane of an optical system due to reflection from the lens surface, which is generally darker in brightness and is offset from the original image.

4＜(RS6－RS7)/(SagS6－SagS7)＜10；

Wherein RS6 is the radius of curvature of the image side surface of the third lens element, RS7 is the radius of curvature of the object side surface of the fourth lens element, sagS is the sagittal height of the image side surface of the third lens element, and SagS7 is the sagittal height of the object side surface of the fourth lens element.

Sagittal height (also known as sag) refers to the perpendicular distance between the geometric center of the back surface of the lens and the diametric plane of the lens.

That is, (RS 6-RS 7)/(SagS-SagS 7) may be any number between 4 and 10, for example 4.1, 5, 6,7, 8, 9, 9.9, etc.

－2.5＜f45/f＜－0.5；

That is, f45/f may be any number between-2.5 and-0.5, such as-2.49, -2.2, -2, -1.5, -1.2, -1.0, -0.8, -0.51, and the like.

The third lens group 50 has negative power, complements the aberration of the first lens group 10 and the second lens group 30, reduces sensitivity, and improves the imaging resolution of the optical imaging system.

－15＜(CT5－CT4)×100/f45＜－3；

wherein CT4 is the distance between the object side surface and the image side surface of the fourth lens element and CT5 is the distance between the object side surface and the image side surface of the fifth lens element and f45 is the focal length of the second lens assembly, i.e., the combined focal length of the fourth lens element L4 and the fifth lens element L5.

That is, CT5-CT 4). Times.100/f 45 may be any number between-15 and-3, such as-14.9, -14, -10, -8, -5, -3.1, etc.

By reasonably configuring the center thicknesses of the fourth lens L4 and the fifth lens L5, the third lens group 50 has negative power as a whole, and the aberration can be optimized, so that the optical imaging system has a compact structure, and the overall length of the optical imaging system is reduced, which is beneficial to miniaturization.

4＜(D23+D34)×100/TTL＜18；

That is, (d23+d34) ×100/TTL may be any number between 4 and 18, for example 4.1, 6, 8, 10, 12, 15, 16, 17.9, etc.

0.1≤(|RS4|+|RS7|)/(|RS5|+|RS6|)＜2；

That is, (|RS4|+|RS7|)/(|RS5|+|RS6|) may be any number between 0.1 and 2, such as 0.15, 0.7, 1.0, 1.2, 1.5, 1.9, 1.99, etc.

0.5＜Imgh/f＜1；

That is, imgh/f can be any number between 0.5 and 4, such as 0.51, 0.6, 0.7, 0.8, 0.9, 0.99, etc.

3＜TTL/BFL＜7；

That is, TTL/BFL can be any number between 3 and 7, such as 3.1, 3.5, 4, 5, 6, 6.5, 6.9, etc.

2.55＜FOV/CRA＜3.55；

That is, the FOV/CRA may be any number between 2.55 and 3.55, such as 2.56, 2.8, 3.0, 3.2, 3.4, 3.54, etc.

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

First embodiment

Referring to fig. 1-1 and fig. 1-2, fig. 1-1 is a schematic structural diagram of an optical imaging system 100 according to a first embodiment, and fig. 1-2 is a graph of spherical aberration, astigmatism and distortion curves according to the first embodiment of the present invention in order from left to right. As can be seen from fig. 1-1, the optical imaging system 100 of the present embodiment sequentially includes, from an object side to an image side, a first lens L1 having positive optical power, a second lens L2 having negative optical power, a third lens L3 having positive optical power, a fourth lens L4 having negative optical power, a fifth lens L5 having positive optical power, a cover glass 70, and an imaging surface 80. The first lens L1 constitutes the first lens group 10. The second lens L2 and the third lens L3 constitute a second lens group 30. The fourth lens L4 and the fifth lens L5 constitute the third lens group 50. The optical imaging system 100 further includes an infrared-transmissive film (not shown) that is coated on the image side surface S10 of the fifth lens L5.

The first lens L1 is made of glass material, and has an object side surface S1 and an image side surface S2. The object side surface S1 and the image side surface S2 of the first lens L1 are spherical surfaces. The object side surface S1 is convex, and the image side surface S2 is planar.

The second lens element L2 is made of glass material, 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 spherical surfaces. The object side surface S3 is concave, and the image side surface S4 is concave.

The third lens element L3 is made of 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 aspherical surfaces. The object side surface S5 and the image side surface S6 are both convex.

The fourth lens element L4 is made of glass material, 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 spherical surfaces. The object side surface S7 is concave, and the image side surface S8 is concave.

The fifth lens element L5 is made of 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 spherical surfaces. The object side surface S9 is convex, and the image side surface S10 is planar.

The optical imaging system 100 further includes a diaphragm formed by the aperture size of the object side surface S1 of the first lens L1.

In the present embodiment ,f1＝5.65,f＝7.72,f1/f＝0.73;f23＝12.32,f23/f＝1.60;CT2＝0.6,CT3＝1.68,(CT3－CT2)×100/f23＝8.73;RS5＝22.81,RS5/f＝2.95;RS6＝－4.02,RS7＝－3.64,SagS6＝－0.65,SagS7＝－0.73,(RS6－RS7)/(SagS6－SagS7)＝5.28;f45＝－15.43,f45/f＝－2.00;CT4＝0.70,CT5＝1.44,(CT5－CT4)×100/f45＝－4.77;D23＝0.54,D34＝0.77,TTL＝11.0,(D23+D34)×100/TTL＝11.93;|RS4|＝5.66,|RS5|＝22.81,|RS6|＝4.02,|RS7|＝3.64,(|RS4|+|RS7|)/(|RS5|+|RS6|)＝0.35;Imgh＝6.18,Imgh/f＝0.80;BFL＝2.40,TTL/BFL＝4.58;FOV＝42.7,CRA＝15.7,FOV/CRA＝2.72.

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

FNO is the f-number of the optical imaging system in Table 1.

Table 2 shows aspherical data of the first embodiment, where k is a conic coefficient of each surface, and A4-a20 are aspherical coefficients of 4 th-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 high pixel resolution while satisfying miniaturization.

Second embodiment

Referring to fig. 2-1 and fig. 2-2, 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 curves according to a second embodiment of the present invention from left to right. As can be seen from fig. 2-1, the optical imaging system 100 of the present embodiment sequentially includes, from an object side to an image side, a first lens L1 having positive optical power, a second lens L2 having negative optical power, a third lens L3 having positive optical power, a fourth lens L4 having negative optical power, a fifth lens L5 having positive optical power, a cover glass 70, and an imaging surface 80. The first lens L1 constitutes the first lens group 10. The second lens L2 and the third lens L3 constitute a second lens group 30. The fourth lens L4 and the fifth lens L5 constitute the third lens group 50. The optical imaging system 100 further includes an infrared-transmissive film (not shown) that is coated on the image side surface S8 of the fourth lens L4.

The first lens L1 is made of glass material, and has an object side surface S1 and an image side surface S2. The object side surface S1 and the image side surface S2 of the first lens L1 are spherical surfaces. The object side surface S1 is convex, and the image side surface S2 is convex.

The second lens element L2 is made of plastic material, 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 aspherical surfaces. The object side surface S3 is concave, and the image side surface S4 is convex.

The third lens element L3 is made of 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 spherical surfaces. The object side surface S5 and the image side surface S6 are both convex.

The fifth lens element L5 is made of 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 spherical surfaces. The object side surface S9 is concave, and the image side surface S10 is convex.

In the present embodiment ,f1＝4.88,f＝7.8,f1/f＝0.63;f23＝5.51,f23/f＝0.71;CT2＝1.19,CT3＝2.04,(CT3－CT2)×100/f23＝15.39;RS5＝29.99,RS5/f＝3.84;RS6＝－3.49,RS7＝－3.10,SagS6＝－0.73,SagS7＝－0.82,(RS6－RS7)/(SagS6－SagS7)＝4.69;f45＝－8.43,f45/f＝－1.08;CT4＝0.80,CT5＝1.65,(CT5－CT4)×100/f45＝－10.14;D23＝0.28,D34＝0.23,TTL＝11.0,(D23+D34)×100/TTL＝4.68;|RS4|＝55.75,|RS5|＝29.99,|RS6|＝3.49,|RS7|＝3.09,(|RS4|+|RS7|)/(|RS5|+|RS6|)＝1.76;Imgh＝6.18,Imgh/f＝0.79;BFL＝2.01,TTL/BFL＝5.48;FOV＝42.1,CRA＝15.6,FOV/CRA＝2.70.

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

FNO is the f-number of the optical imaging system in Table 3.

Table 4 shows aspherical data of the second embodiment, where k is a conic coefficient of each surface, and A4-a20 are aspherical coefficients of 4 th-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 high pixel size while satisfying miniaturization.

Third embodiment

Referring to fig. 3-1 and 3-2, 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 spherical aberration, astigmatism and distortion chart of the third embodiment of the present invention in order from left to right. As can be seen from fig. 3-1, the optical imaging system 100 of the present embodiment sequentially includes, from an object side to an image side, a first lens L1 having positive optical power, a second lens L2 having negative optical power, a third lens L3 having positive optical power, a fourth lens L4 having negative optical power, a fifth lens L5 having positive optical power, a cover glass 70, and an imaging surface 80. The first lens L1 constitutes the first lens group 10. The second lens L2 and the third lens L3 constitute a second lens group 30. The fourth lens L4 and the fifth lens L5 constitute the third lens group 50. The optical imaging system 100 further includes an infrared-transmissive film (not shown) that is coated on the image side S2 of the first lens L1.

In the present embodiment ,f1＝4.23,f＝7.66,f1/f＝0.55;f23＝8.67,f23/f＝1.13;CT2＝0.55,CT3＝1.56,(CT3－CT2)×100/f23＝11.59;RS5＝95,RS5/f＝12.4;RS6＝－3.00,RS7＝－5.10,SagS6＝－0.62,SagS7＝－0.38,(RS6－RS7)/(SagS6－SagS7)＝8.53;f45＝－13.3,f45/f＝－1.74;CT4＝0.55,CT5＝1.55,(CT5－CT4)×100/f2345＝－7.49;D23＝0.44,D34＝0.10,TTL＝10.88,(D23+D34)×100/TTL＝5.00;|RS4|＝4.54,|RS5|＝95,|RS6|＝3,|RS7|＝5.10,(|RS4|+|RS7|)/(|RS5|+|RS6|)＝0.1;Imgh＝6.18,Imgh/f＝0.81;BFL＝3.28,TTL/BFL＝5.483.31;FOV＝43.4,CRA＝12.5,FOV/CRA＝3.47.

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

FNO is the f-number of the optical imaging system in Table 5.

Table 6 shows aspherical data of the third embodiment, where k is a conic coefficient of each surface, and A4-a20 are aspherical coefficients of 4 th-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 high pixel size while satisfying miniaturization.

Fourth embodiment

Referring to fig. 4-1 and fig. 4-2, 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 present invention from left to right. As can be seen from fig. 4-1, the optical imaging system 100 of the present embodiment sequentially includes, from the object side to the image side, a first lens L1 having positive optical power, a second lens L2 having negative optical power, a third lens L3 having positive optical power, a fourth lens L4 having negative optical power, a fifth lens L5 having positive optical power, a cover glass 70, and an imaging surface 80. The first lens L1 constitutes the first lens group 10. The second lens L2 and the third lens L3 constitute a second lens group 30. The fourth lens L4 and the fifth lens L5 constitute the third lens group 50. The optical imaging system 100 further includes an infrared-transmissive film (not shown) that is coated on the image side S2 of the first lens L1.

In the present embodiment ,f1＝4.97,f＝7.86,f1/f＝0.63;f23＝7.63,f23/f＝0.97;CT2＝0.50,CT3＝1.81,(CT3－CT2)×100/f23＝17.21;RS5＝11.36,RS5/f＝1.45;RS6＝－4.00,RS7＝－4.77,SagS6＝－0.77,SagS7＝－0.64,(RS6－RS7)/(SagS6－SagS7)＝6.16;f45＝－16.11,f45/f＝－2.05;CT4＝0.50,CT5＝1.44,(CT5－CT4)×100/f45＝－5.87;D23＝1.14,D34＝0.49,TTL＝11.08,(D23+D34)×100/TTL＝14.69;|RS4|＝3.48,|RS5|＝11.36,|RS6|＝4.00,|RS7|＝4.76,(|RS4|+|RS7|)/(|RS5|+|RS6|)＝0.54;Imgh＝6.18,Imgh/f＝0.79;BFL＝2.41,TTL/BFL＝4.59;FOV＝42.7,CRA＝15.0,FOV/CRA＝2.85.

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

FNO is the f-number of the optical imaging system in Table 7.

Table 8 shows aspherical data of the fourth embodiment, where k is a conic coefficient of each surface, and A4-a20 are aspherical coefficients of 4 th-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 high pixel size while satisfying miniaturization.

Fifth embodiment

Referring to fig. 5-1 and fig. 5-2, 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 spherical aberration, astigmatism and distortion chart of the fifth embodiment of the present invention in order from left to right. As can be seen from fig. 5-1, the optical imaging system 100 of the present embodiment sequentially includes, from the object side to the image side, a first lens L1 having positive optical power, a second lens L2 having negative optical power, a third lens L3 having positive optical power, a fourth lens L4 having negative optical power, a fifth lens L5 having positive optical power, a cover glass 70, and an imaging surface 80. The first lens L1 constitutes the first lens group 10. The second lens L2 and the third lens L3 constitute a second lens group 30. The fourth lens L4 and the fifth lens L5 constitute the third lens group 50. The optical imaging system 100 further includes an infrared-transmissive film (not shown) that is coated on the image side S2 of the first lens L1.

The fifth lens element L5 is made of 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 spherical surfaces. The object side surface S9 is convex, and the image side surface S10 is concave.

In the present embodiment ,f1＝7.30,f＝7.77,f1/f＝0.68;f23＝16.80,f23/f＝2.16;CT2＝0.50,CT3＝1.86,(CT3－CT2)×100/f23＝8.07;RS5＝37.53,RS5/f＝4.83;RS6＝－5.40,RS7＝－3.64,SagS6＝－0.51,SagS7＝－0.78,(RS6－RS7)/(SagS6－SagS7)＝6.43;f45＝－14.85,f45/f＝－1.91;CT4＝0.70,CT5＝1.46,(CT5－CT4)×100/f45＝－5.14;D23＝1.01,D34＝0.92,TTL＝11.0,(D23+D34)×100/TTL＝17.54;|RS4|＝4.32,|RS5|＝37.53,|RS6|＝5.40,|RS7|＝3.64,(|RS4|+|RS7|)/(|RS5|+|RS6|)＝0.19;Imgh＝6.18,Imgh/f＝0.80;BFL＝2.01,TTL/BFL＝5.49;FOV＝42.5,CRA＝15.6,FOV/CRA＝2.72.

In the present embodiment, the optical imaging system 100 satisfies the conditions of table 9 below.

FNO is the f-number of the optical imaging system in Table 9.

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

Sixth embodiment

Referring to fig. 6-1 and fig. 6-2, 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 curves according to the sixth embodiment of the present invention sequentially from left to right. As can be seen from fig. 6-1, the optical imaging system 100 of the present embodiment sequentially includes, from an object side to an image side, a first lens L1 having positive optical power, a second lens L2 having negative optical power, a third lens L3 having positive optical power, a fourth lens L4 having negative optical power, a fifth lens L5 having negative optical power, a cover glass 70, and an imaging surface 80. The first lens L1 constitutes the first lens group 10. The second lens L2 and the third lens L3 constitute a second lens group 30. The fourth lens L4 and the fifth lens L5 constitute the third lens group 50. The optical imaging system 100 further includes an infrared-transmissive film (not shown) that is coated on the image side S2 of the first lens L1.

The fifth lens element L5 is made of 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 aspherical surfaces. The object side surface S9 is concave, and the image side surface S10 is convex.

In the present embodiment ,f1＝5.87,f＝7.77,f1/f＝0.76;f23＝6.21,f23/f＝0.8;CT2＝0.60,CT3＝2.07,(CT3－CT2)×100/f23＝23.75;RS5＝8.59,RS5/f＝1.11;RS6＝－4.78,RS7＝－3.95,SagS6＝－0.62,SagS7＝－0.74,(RS6－RS7)/(SagS6－SagS7)＝7.19;f45＝－6.76,f45/f＝－0.87;CT4＝0.70,CT5＝1.21,(CT5－CT4)×100/f45＝－7.54;D23＝0.91,D34＝0.32,TTL＝11.00,(D23+D34)×100/TTL＝11.12;|RS4|＝4.03,|RS5|＝8.59,|RS6|＝4.78,|RS7|＝3.95,(|RS4|+|RS7|)/(|RS5|+|RS6|)＝0.60;Imgh＝6.18,Imgh/f＝0.80;BFL＝2.00,TTL/BFL＝5.50;FOV＝43.3,CRA＝15.0,FOV/CRA＝2.89.

In the present embodiment, the optical imaging system 100 satisfies the conditions of the following tables 10 and 11.

FNO is the f-number of the optical imaging system in Table 10.

Table 11 shows aspherical data of the sixth embodiment, where k is a conic coefficient of each surface, and A4-a20 are aspherical coefficients of 4 th-20 th order of each surface.

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

As shown in fig. 7, the image capturing device 200 includes the optical imaging system 100 and the photosensitive element 210 of the present invention. 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 photosensitive coupling element (Charge Coupled Device, CCD) or a complementary metal oxide semiconductor element (Complementary Metal-Oxide Semiconductor Sensor, CMOS sensor).

Reference is made to the above description for other features of the image capturing device 200, and the description is omitted herein.

As shown in fig. 8, the present invention further provides an electronic device 300, which includes a device main body 310 and the image capturing apparatus 200 of the present invention. The orientation apparatus 200 is mounted on the device 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 cell phone, a camera, a smart bracelet, a smart watch, smart glasses, and the like.

While the invention has been described with reference to certain preferred embodiments, it will be understood by those skilled in the art that various changes and substitutions of equivalents may be made and equivalents will be apparent to those skilled in the art without departing from the scope of the invention. Therefore, the protection scope of the invention is subject to the protection scope of the claims.

Claims

1. An optical imaging system is characterized by comprising a first lens group, a second lens group and a third lens group, wherein the optical imaging system comprises the following components in sequence from an object side to an image side:

The first lens group having positive optical power;

the second lens group having positive optical power; and

The third lens group having negative optical power;

The first lens group consists of a first lens, wherein the first lens has positive focal power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a convex surface or a plane;

The second lens group is composed of a second lens and a third lens, the second lens has negative focal power, and the third lens has positive focal power; the third lens group is composed of a fourth lens and a fifth lens, the fourth lens has negative focal power, and the fifth lens has focal power; and the optical imaging system satisfies the following conditional expression:

1<RS5/f<20；

2.55＜FOV/CRA＜3.55；

0＜f1/f＜1；

0＜f23/f＜3；

-2.5<f45/f<-0.5；

Wherein RS5 is a radius of curvature of the object side surface of the third lens, f is an effective focal length of the optical imaging system, f1 is a focal length of the first lens of the optical imaging system, FOV is a viewing angle in a diagonal direction of the optical imaging system, CRA is a chief ray incident angle of the optical imaging system, f23 is a focal length of the second lens group, and f45 is a focal length of the third lens group.

2. The optical imaging system of claim 1, wherein the object-side surface of the second lens is concave, and the image-side surface is convex or concave; the object side surface and the image side surface of the third lens are both convex.

3. The optical imaging system of claim 1, wherein the fourth lens element has a concave object-side surface and a concave image-side surface; the object side surface of the fifth lens is a concave surface or a convex surface, and the image side surface is a concave surface, a convex surface or a plane.

4. The optical imaging system of claim 1, wherein one of the first lens group, the second lens group, and the third lens group is an aspherical lens.

5. The optical imaging system of claim 1, wherein an object side or image side of one or more of the first lens group, the second lens group, and the third lens group is provided with an infrared-transmissive film.

6. The optical imaging system of claim 1, further comprising a diaphragm having an effective diameter that is the first lens object side aperture.

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

5＜(CT3-CT2)×100/f23＜30；

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

4＜(RS6-RS7)/(SagS6-SagS7)＜10；

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

-15＜(CT5-CT4)×100/f45＜-3；

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

4＜(D23+D34)×100/TTL＜18；

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

0.1≤(|RS4|+|RS7|)/(|RS5|+|RS6|)＜2；

Wherein RS4 is a radius of curvature of the image side surface of the second lens element, RS5 is a radius of curvature of the object side surface of the third lens element, RS6 is a radius of curvature of the image side surface of the third lens element, and RS7 is a radius of curvature of the object side surface of the fourth lens element.

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

0.5＜Imgh/f＜1；

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

3<TTL/BFL<7；

14. An image capturing apparatus, comprising:

The optical imaging system of any of claims 1-13; and

15. An electronic device, comprising:

an apparatus main body;

The image capturing device of claim 14, mounted on the apparatus body.