WO2022104749A1

WO2022104749A1 - Optical imaging system, image capture module, and electronic device

Info

Publication number: WO2022104749A1
Application number: PCT/CN2020/130644
Authority: WO
Inventors: 谢晗; 张文燕; 李明
Original assignee: 欧菲光集团股份有限公司; 江西晶超光学有限公司
Priority date: 2020-11-20
Filing date: 2020-11-20
Publication date: 2022-05-27

Abstract

An optical imaging system (10), an image capture module (100), and an electronic device (200). The optical imaging system (10) sequentially comprises, from an object side to an image side along an optical axis: a prism (L0); a first lens (L1) having refractive power, an object side surface (S5) of the first lens (L1) being convex near the optical axis; a second lens (L2) having refractive power; a third lens (L3) having refractive power; a fourth lens (L4) having refractive power, an image side surface (S12) of the fourth lens (L4) being convex near the optical axis; a fifth lens (L5) having refractive power; and a sixth lens (L6) having refractive power. The optical imaging system (10) satisfies the following conditional expression: 1.7<CT/TTL10<3, where CT represents the sum of air gaps from an image side surface (S6) of the first lens (L1) to an object side surface (S15) of the sixth lens (L6) on the optical axis, and TTL represents the distance from the object side surface (S5) of the first lens (L1) to an imaging surface (S19) of the optical imaging system (10) on the optical axis. Thus, there are more spaces in the total length of the optical imaging system (10), such that the requirements of light-weighting and thinning can be achieved; moreover, refractive power is reasonably distributed, such that telephoto characteristics can be achieved, and better optical performances can be obtained.

Description

Optical imaging system, imaging module and electronic device

technical field

The invention relates to the technical field of optical imaging, in particular to an optical imaging system, an imaging module and an electronic device.

Background technique

In recent years, with the improvement of people's living standards and the continuous development of science and technology, the upgrading of portable electronic products such as smartphones has accelerated, and the camera lenses mounted on them have become more and more diversified to meet the needs of consumers, such as wide-angle lenses, Telephoto lens, TOF lens, etc.

In the process of realizing this application, the inventor found that there are at least the following problems in the prior art: due to the development trend of light and thin electronic products, the existing electronic products are usually equipped with ultra-thin lenses with a short focal length, but the imaging effect is not good when shooting long-range scenes. However, telephoto lenses are generally longer in size, making it difficult to install on thin and light electronic devices. Therefore, how to realize a telephoto lens with good imaging quality and meeting the requirements of light and thin is an urgent problem to be solved at present.

SUMMARY OF THE INVENTION

In view of the above content, it is necessary to propose an optical imaging system, an imaging module and an electronic device to solve the above problems.

The embodiment of the present application proposes an optical imaging system, which includes sequentially along the optical axis from the object side to the image side:

a prism, the prism includes an incident surface, a reflection surface and an exit surface;

a first lens with refractive power, the object side surface of the first lens is convex at the near optical axis;

a second lens having refractive power;

a third lens having refractive power;

a fourth lens with refractive power, the image side surface of the fourth lens is convex at the near optical axis;

a fifth lens with refractive power;

a sixth lens with refractive power;

The optical imaging system satisfies the following conditional formula:

1.7<CT/TTL*10<3;

where CT is the sum of the air gaps on the optical axis from the image side of the first lens to the object side of the sixth lens, and TTL is the distance between the object side of the first lens and the imaging surface of the optical imaging system. distance on the optical axis.

The above optical imaging system deflects the light transmission route in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so as to convert the system volume originally stacked on the vertical axis into a horizontal direction, so that the total length of the optical imaging system has More space can meet the needs of light and thin, and rationally distribute the bending force, compress the gap of each lens, make it more compact, and also make the design of the lens barrel structure more simple, while ensuring the telephoto characteristics. The total length of the optical imaging system will not increase excessively, and the imaging quality can also be effectively guaranteed.

In some embodiments, a diaphragm is further included, the diaphragm is arranged on the object side of the first lens, the refractive power of the first lens is positive, the refractive power of the second lens is positive, and the refractive power of the first lens is positive. The refractive power of the third lens is negative, the refractive power of the fourth lens is positive, the object side of the fifth lens is concave at the near optical axis, the image side is convex at the near optical axis, and the sixth lens is concave at the near optical axis. The refractive power of the lens is negative, and its image side is concave at the near optical axis.

In this way, the overall size of the optical imaging system can be effectively reduced by reasonably configuring the refractive power and the surface shape of each lens to meet the characteristics of miniaturization.

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

f*ImgH/10≥1.75mm ² ;

Wherein, f is the effective focal length of the optical imaging system, and ImgH is half of the image height corresponding to the maximum angle of view of the optical imaging system.

In this way, the number of pixels can be increased by increasing the size of the chip to ensure the resolution of the telephoto lens. If it is lower than the lower limit, it will be difficult to increase the pixels, and the focal length is too short, which is not conducive to the shooting of the telephoto lens when the background is blurred. experience.

0.8mm ^-1 <tanω/P*100<3mm ^-1 ;

Wherein, ω is half of the maximum angle of view of the optical imaging system, the prism includes an incident surface, a reflecting surface and an exit surface, and the prism is cut into equal parts by the surfaces perpendicular to the incident surface and the reflecting surface at the same time. For a right-angled triangle, p is the length of the hypotenuse of the isosceles right-angled triangle.

In this way, the size of the field of view can be controlled within a small range, making it easier for the light to reach the lens from the reflective surface of the prism, and it is not easy to cause harmful light paths such as total reflection. Phenomenon, if it is lower than the lower limit, the size of the prism is too large, which leads to the enlargement of the entire module, which does not meet the trend of thinning.

7<D/f*100<14;

Wherein, D is the distance from the exit surface of the prism to the object side of the first lens on the optical axis, and f is the effective focal length of the optical imaging system.

In this way, by controlling the distance from the exit surface of the prism to the object side of the first lens on the optical axis, the divergence angle of the light beam at the prism can be controlled, so that the optical imaging system has higher imaging quality, and in addition, the prism and lens can be reduced. Assembly difficulty. If it is higher than the upper limit, the distance will be too large, the light will diverge widely, the aperture of the lens will increase, and the overall lens will be enlarged. If it is lower than the lower limit, the space will be too small, and the assembly difficulty will increase.

0.22<(R7+R8)/(R7-R8)<3.3;

Wherein, R7 is the radius of curvature of the object side of the fourth lens at the optical axis, and R8 is the radius of curvature of the image side of the fourth lens at the optical axis.

In this way, the fourth lens can provide a part of the positive refractive power, and the image side of the fourth lens is convex at the optical axis. By rationally optimizing the curvature radius of the object side and the image side of the fourth lens at the optical axis, the third lens can be reduced. The air gap between the image side surface and the object side surface of the fourth lens makes the arrangement between the lenses more compact, and at the same time, the fifth lens and the sixth lens can be prevented from being bent too much.

f12/f>0.49;

Wherein, f12 is the combined focal length of the first lens and the second lens, and f is the effective focal length of the optical imaging system.

In this way, the first lens and the second lens are positive lenses, which can jointly provide a positive refractive power for the optical imaging system, and the value of the combined focal length of the first lens and the second lens is reasonably controlled not to be lower than the lower limit, so that the first lens and the second lens can be properly controlled. The refractive power of the first lens and the second lens will not be too large, which ensures that the entire optical imaging system has a longer focal length value, so as to achieve a background blurred shooting experience.

-4<f4/R8<-0.9;

Wherein, f4 is the focal length of the fourth lens, and R8 is the radius of curvature of the image side surface of the fourth lens at the optical axis.

In this way, the image side of the fourth lens is convex at the near optical axis, and is curved in the same direction as the object side of the fifth lens.

0.15<v3/(v1+v2)<0.24;

Wherein, v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, and v3 is the Abbe number of the third lens.

In this way, the first lens and the second lens are positive lenses, which can provide positive refractive power and control the focal length of the entire optical imaging system, and the third lens is a negative lens, which is configured with a smaller Abbe number to correct spherical aberration. , can improve the resolution. If it is higher than the upper limit, the ability of the third lens to correct aberrations is insufficient, the modulation transfer function of the optical imaging system decreases, and the resolution is reduced. If it is lower than the lower limit, the material cost is too high, which is not conducive to actual production.

0.8<R9/R10<1.3;

Wherein, R10 is the radius of curvature of the object side of the fifth lens at the optical axis, and R11 is the radius of curvature of the image side of the fifth lens at the optical axis.

In this way, by optimizing the curvature radius of the fifth lens, the shape of the object side surface and the image side surface can be made to be similar, and the shape curvature is smaller, which reduces the sensitivity of optical performance.

The embodiment of the present application also proposes an imaging module, including:

optical imaging systems; and

A photosensitive element, the photosensitive element is arranged on the image side of the optical imaging system.

The imaging module according to the embodiment of the present invention includes an optical imaging system, and the optical imaging system deflects the light transmission route in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so that the light originally accumulated on the longitudinal axis can be removed. The volume of the system is turned to the horizontal direction, so that the total length of the optical imaging system has more space, which can meet the needs of light and thin, and the bending force is reasonably distributed to compress the gap of each lens to make it more compact, which also makes the lens barrel structure more compact. The design of the optical imaging system tends to be simpler, and at the same time, the total length of the optical imaging system will not be excessively increased under the guarantee of the telephoto characteristics, and the imaging quality can be effectively guaranteed.

An embodiment of the present invention provides an electronic device, comprising: a casing and the imaging module of the above-mentioned embodiment, wherein the imaging module is mounted on the casing.

The electronic device of the embodiment of the present invention includes an imaging module, and the optical imaging system in the imaging module deflects the light transmission route in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so that the original The volume of the system stacked on the vertical axis is turned to the horizontal direction, so that the total length of the optical imaging system has more space, which can meet the needs of light and thin, and rationally distribute the bending force, compress the gap between each lens, and make it more compact, It also makes the design of the lens barrel structure more simple, and at the same time, the total length of the optical imaging system will not increase excessively while ensuring the telephoto characteristic, and the imaging quality can also be effectively guaranteed.

Description of drawings

The above and/or additional aspects and advantages of the present invention may become apparent and readily understood from the following description of embodiments in conjunction with the accompanying drawings, wherein:

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

FIG. 2 is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the first embodiment of the present invention.

FIG. 3 is a schematic structural diagram of an optical imaging system according to a second embodiment of the present invention.

4 is a graph of spherical aberration, astigmatism and distortion of the optical imaging system in the second embodiment of the present invention.

FIG. 5 is a schematic structural diagram of an optical imaging system according to a third embodiment of the present invention.

6 is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the third embodiment of the present invention.

FIG. 7 is a schematic structural diagram of an optical imaging system according to a fourth embodiment of the present invention.

FIG. 8 is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the fourth embodiment of the present invention.

FIG. 9 is a schematic structural diagram of an optical imaging system according to a fifth embodiment of the present invention.

10 is a graph showing spherical aberration, astigmatism and distortion of the optical imaging system in the fifth embodiment of the present invention.

FIG. 11 is a schematic structural diagram of an image capturing module according to an embodiment of the present invention.

FIG. 12 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.

Description of main component symbols

Electronic device 200

Image acquisition module 100

Optical imaging system 10

The first lens L1

Second lens L2

The third lens L3

Fourth lens L4

Fifth lens L5

The sixth lens L6

Infrared filter L7

Aperture STO

Incident surface S1

Reflector S2

Exit surface S3

Object side S5, S7, S9, S11, S13, S15, S17

Like side S6, S8, S10, S12, S14, S16, S18

Imaging surface S19

Photosensitive element 20

Shell 210

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", " Rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outer", clockwise, "counterclockwise" The relationship is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore Can not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for description purposes, and cannot be interpreted as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus , the features defined with "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more , unless otherwise specifically defined.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; it can be mechanical connection, electrical connection or can communicate with each other; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction of two elements relation. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In the present invention, unless otherwise expressly specified and limited, a first feature "on" or "under" a second feature may include direct contact between the first and second features, or may include the first and second features Not directly but through additional features between them. Also, the first feature being "above", "over" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is level higher than the second feature. A first feature "below", "below" and "beneath" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the first feature has a lower level than the second feature.

The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are only examples and are not intended to limit the invention. Furthermore, the present disclosure may repeat reference numerals and/or reference letters in different instances for the purpose of simplicity and clarity and not in itself indicative of a relationship between the various embodiments and/or arrangements discussed. In addition, the present disclosure provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the application of other processes and/or the use of other materials.

Referring to FIG. 1 , an optical imaging system 10 according to an embodiment of the present invention sequentially includes an isosceles right-angle prism L0, a first lens L1 with positive refractive power, a second lens L2 with refractive power, The third lens L3 having refractive power, the fourth lens L4 having refractive power, the fifth lens L5 having refractive power, and the sixth lens L6 having refractive power.

The first lens L1 has an incident surface S1, a reflective surface S2 and an exit surface S3, the first lens L1 has an object side S5 and an image side S6, and the object side S5 of the first lens L1 is a convex surface at the near optical axis; the second lens L2 Has an object side S7 and an image side S8; the third lens L3 has an object side S9 and an image side S10, the fourth lens L4 has an object side S11 and an image side S12, and the object side S11 of the fourth lens L4 is convex at the near optical axis The fifth lens L5 has the object side S13 and the image side S14; the sixth lens L6 has the object side S15 and the image side S16.

The optical imaging system 10 satisfies the following relationship:

1.7<CT/TTL*10<3;

Among them, CT is the sum of the air gaps on the optical axis from the image side S6 of the first lens L1 to the object side S15 of the sixth lens L6, and TTL is the object side S6 of the first lens L1 to the imaging surface S19 of the optical imaging system 10. distance on the optical axis.

The above-mentioned optical imaging system 10 deflects the light transmission path in the optical imaging system 10 by adding a reflective prism, so that the light no longer propagates in a straight line, so as to convert the system volume originally stacked on the vertical axis into a horizontal direction, so that the optical imaging system 10 has a horizontal direction. There is more space in the total length, which can meet the needs of light and thin, and rationally distribute the bending force, compress the gap between each lens, make it more compact, and also make the design of the lens barrel structure more simple, while ensuring long Under the focal characteristics, the total length of the optical imaging system 10 will not be excessively increased, and the imaging quality can also be effectively guaranteed. If it is lower than the lower limit, the optical imaging system 10 will be over-compressed, the deflection angle of the light will be too large under the smaller air gap, and the degree of freedom will be reduced, which is not conducive to the telephoto characteristic; if it is higher than the upper limit, the lenses will not be compact enough, and the total length will be too long. , the actual assembly and production is difficult.

During imaging, the light incident from the outside enters the incident surface S1 of the isosceles right-angle prism L0 along the optical axis LA, is refracted by the reflective surface S2 and then exits from the exit surface S3, and passes through the first lens L1, the first lens L1, the second lens along the optical axis, and the like. After the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6, they reach the imaging surface S19.

In some embodiments, the optical imaging system 10 further includes a diaphragm STO, the diaphragm STO is arranged on the object side S5 of the first lens L1, the refractive power of the first lens L1 is positive, and the refractive power of the second lens L2 is positive , the refractive power of the third lens L3 is negative, the refractive power of the fourth lens L4 is positive, the object side S13 of the fifth lens L5 is concave at the near optical axis, the image side S14 is convex at the near optical axis, and the sixth The refractive power of lens L6 is negative, and its image side surface S16 is concave at the near optical axis.

In this way, the overall size of the optical imaging system 10 can be effectively reduced by properly configuring the refractive power and the surface shape of each lens, so as to meet the characteristics of miniaturization.

In some embodiments, the optical imaging system 10 further includes an infrared filter L7, and the infrared filter L7 has an object side S17 and an image side S18. The infrared filter L7 is arranged on the image side of the sixth lens L6, and the infrared filter L7 is used to filter the imaged light, specifically for isolating the infrared light, preventing the infrared light from being received by the photosensitive element, thereby preventing the infrared light from affecting the normal image. The color and sharpness are affected, thereby improving the imaging quality of the optical imaging system 10 . Preferably, the infrared filter L7 is an infrared cut-off filter.

In some embodiments, the optical imaging system 10 satisfies the following conditional formula:

f*ImgH/10≥1.75mm ² ;

Among them, f is the effective focal length of the optical imaging system, and ImgH is half of the image height corresponding to the maximum angle of view of the optical imaging system.

0.8mm ^-1 <tanω/P*100<3mm ^-1 ;

Among them, ω is half of the maximum field of view of the optical imaging system 10, the isosceles right-angle prism L0 is truncated into an isosceles right triangle by the surfaces of the vertical incident surface S1 and the reflection surface S2 at the same time, p is the hypotenuse length of the isosceles right triangle .

7<D/f*100<14;

Wherein, D is the distance on the optical axis from the exit surface S3 of the isosceles right-angle prism L0 to the object side surface S5 of the first lens L1 , and f is the effective focal length of the optical imaging system 10 .

In this way, by controlling the distance from the exit surface S3 of the isosceles right angle prism L0 to the object side surface S5 of the first lens L1 on the optical axis, the divergence angle of the light beam at the prism can be controlled, so that the optical imaging system 10 has higher imaging quality , in addition, the assembly difficulty of the prism and the lens can be reduced. If it is higher than the upper limit, the distance will be too large, the light will diverge widely, the aperture of the lens will increase, and the overall lens will be enlarged. If it is lower than the lower limit, the space will be too small, and the assembly difficulty will increase.

0.22<(R7+R8)/(R7-R8)<3.3;

Wherein, R7 is the radius of curvature of the object side S11 of the fourth lens L4 at the optical axis, and R8 is the radius of curvature of the image side S12 of the fourth lens L4 at the optical axis.

In this way, the fourth lens L4 can provide a part of the positive refractive power, and the image side S12 of the fourth lens L4 is a convex surface at the optical axis, and the curvature radius of the object side S11 and the image side S12 of the fourth lens L4 at the optical axis is reasonably optimized, The air gap between the image side S9 of the third lens L3 and the object side S11 of the fourth lens S10 can be reduced, so that the arrangement between the lenses is more compact, and at the same time, the fifth lens L5 and the sixth lens L6 can be prevented from being bent too much. big.

f12/f>0.49;

Wherein, f12 is the combined focal length of the first lens L1 and the second lens L2 , and f is the effective focal length of the optical imaging system 10 .

In this way, the first lens L1 and the second lens L2 are positive lenses, which can jointly provide a positive refractive power for the optical imaging system 10, and the value of the combined focal length of the first lens L1 and the second lens L2 is reasonably controlled not to be lower than the lower limit, so that the The refractive power of the first lens L1 and the second lens L2 will not be too large, so as to ensure that the entire optical imaging system 10 has a longer focal length value, so as to achieve a blurred background shooting experience.

-4<f4/R8<-0.9;

Wherein, f4 is the focal length of the fourth lens L4, and R8 is the radius of curvature of the image side surface S12 of the fourth lens L4 at the optical axis.

In this way, the image side S12 of the fourth lens L4 is convex at the near optical axis, and is curved in the same direction as the object side S13 of the fifth lens L5, which satisfies the above relationship, and the optical imaging system 10 has a better balance of chromatic aberration and distortion. Ability.

0.15<v3/(v1+v2)<0.24;

Wherein, v1 is the Abbe number of the first lens L1, v2 is the Abbe number of the second lens L3, and v3 is the Abbe number of the third lens L3.

In this way, the first lens L1 and the second lens L2 are positive lenses, which can provide positive refractive power and control the focal length of the entire optical imaging system 10, and the third lens L3 is a negative lens, and a smaller Abbe is configured for the third lens L3 If it is higher than the upper limit, the ability of the third lens L3 to correct the aberration is insufficient, the modulation transfer function of the optical imaging system 10 will decrease, and the resolution will be reduced. If it is lower than the lower limit, the material cost will be too high. Not conducive to actual production.

0.8<R9/R10<1.3;

Wherein, R10 is the radius of curvature of the object side S13 of the fifth lens L5 at the optical axis, and R11 is the radius of curvature of the image side S14 of the fifth lens L5 at the optical axis.

In this way, by optimizing the curvature radius of the fifth lens L5, the shape of the object side surface and the image side surface can be made to be similar, and the shape curvature is smaller, which reduces the sensitivity of optical performance.

In some embodiments, the object side surface and the image side surface of the first lens L1 to the sixth lens L6 are all aspherical surfaces.

Among them, the surface shape of the aspheric surface is determined by the following formula:

where Z is the longitudinal distance between any point on the aspheric surface and the vertex of the surface, r is the distance from any point on the aspheric surface to the optical axis, c is the vertex curvature (the inverse of the radius of curvature), k is the conic constant, and Ai is the i-th aspheric surface order correction factor.

first embodiment

Referring to FIG. 1 , the optical imaging system 10 of the first embodiment sequentially includes an isosceles right-angle prism L0, a diaphragm STO, a first lens L1 with positive refractive power, and a The second lens L2, the third lens L3 with negative refractive power, the fourth lens L4 with positive refractive power, the fifth lens L5 with negative refractive power, the sixth lens L6 with negative refractive power, and the infrared filter L7 .

The object side S5 of the first lens L1 is convex at the near optical axis, and the image side S6 is concave at the near optical axis; the object side S7 of the second lens L2 is convex at the near optical axis, and the image side S8 is near the optical axis. The optical axis is concave; the object side S9 of the third lens L3 is concave at the near optical axis, and the image side S10 is concave at the near optical axis; the object side S11 of the fourth lens L4 is convex at the near optical axis, and the image side S10 is concave at the near optical axis. The side S12 is convex at the near optical axis; the object side S13 of the fifth lens L5 is concave at the near optical axis, and the image side S14 is convex at the near optical axis; the object side S15 of the sixth lens L6 is at the near optical axis It is concave, and the image side S16 is concave at the near optical axis.

The object side S5 of the first lens L1 is a convex surface near the circumference, and the object side S7 of the second lens L2 is a convex surface near the circumference, and the image side S8 is a concave surface near the circumference; The object side S9 of the third lens L3 is concave at the near circumference, and the image side S10 is concave at the near circumference; the object side S11 of the fourth lens L4 is convex at the near circumference, and the image side S12 is convex at the near circumference; The object side S13 of the fifth lens L5 is concave near the circumference, and the image side S14 is convex near the circumference; the object side S15 of the sixth lens L6 is concave near the circumference, and the image side S16 is convex near the circumference.

The reference wavelengths of the focal length, refractive index, and Abbe number in the first embodiment are all 587.5617 nm, and the optical imaging system 10 in the first embodiment satisfies the conditions in the following table.

Table 1

It should be noted that, in Table 1, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, and TTL is the object side of the first lens to The distance between the imaging surface of the optical imaging system and the optical axis, the Y radius is the radius of curvature of each surface at the optical axis.

Table 2

FIG. 2 shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the first embodiment, wherein the longitudinal spherical aberration curve represents the deviation of the focusing point of light of different wavelengths after passing through each lens of the optical imaging system 10 ; The astigmatism curve represents the meridional image plane curvature and the sagittal image plane curvature; the distortion curve represents the corresponding distortion value for different field angles. It can be seen from FIG. 2 that the optical imaging system 10 provided in the first embodiment can achieve good imaging quality.

Second Embodiment

Referring to FIG. 3 , the optical imaging system 10 of the second embodiment sequentially includes an isosceles right-angle prism L0, a diaphragm STO, a first lens L1 with a positive refractive power, a The second lens L2, the third lens L3 with negative refractive power, the fourth lens L4 with positive refractive power, the fifth lens L5 with negative refractive power, the sixth lens L6 with negative refractive power, and the infrared filter L7 .

The object side S5 of the first lens L1 is a convex surface near the circumference, and the object side S7 of the second lens L2 is a convex surface near the circumference, and the image side S8 is a concave surface near the circumference; The object side S9 of the third lens L3 is convex at the near circumference, and the image side S10 is concave at the near circumference; the object side S11 of the fourth lens L4 is convex at the near circumference, and the image side S12 is convex at the near circumference; The object side S13 of the fifth lens L5 is concave near the circumference, and the image side S14 is convex near the circumference; the object side S15 of the sixth lens L6 is concave near the circumference, and the image side S16 is convex near the circumference.

The reference wavelengths of the focal length, refractive index, and Abbe number in the second embodiment are all 587.5618 nm, and the optical imaging system 10 in the second embodiment satisfies the conditions in the following table.

table 3

It should be noted that, in Table 3, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, and TTL is the object side of the first lens to The distance between the imaging surface of the optical imaging system and the optical axis, the Y radius is the radius of curvature of each surface at the optical axis.

Table 4

FIG. 4 shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the second embodiment, wherein the longitudinal spherical aberration curve represents the deviation of the focusing point of light of different wavelengths after passing through each lens of the optical imaging system 10 ; The astigmatism curve represents the meridional image plane curvature and the sagittal image plane curvature; the distortion curve represents the corresponding distortion value for different field angles. It can be seen from FIG. 4 that the optical imaging system 10 provided in the second embodiment can achieve good imaging quality.

Third Embodiment

Referring to FIG. 5 , the optical imaging system 10 of the third embodiment sequentially includes an isosceles right-angle prism L0, a diaphragm STO, a first lens L1 with positive refractive power, and a The second lens L2, the third lens L3 with negative refractive power, the fourth lens L4 with positive refractive power, the fifth lens L5 with positive refractive power, the sixth lens L6 with negative refractive power, and the infrared filter L7 .

The reference wavelengths of the focal length, refractive index, and Abbe number in the third embodiment are all 587.5618 nm, and the optical imaging system 10 in the third embodiment satisfies the conditions in the following table.

table 5

It should be noted that, in Table 5, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, and TTL is the object side of the first lens to The distance between the imaging surface of the optical imaging system and the optical axis, the Y radius is the radius of curvature of each surface at the optical axis.

Table 6

FIG. 6 shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the third embodiment, wherein the longitudinal spherical aberration curve represents the deviation of the focusing point of light of different wavelengths after passing through each lens of the optical imaging system 10 ; The astigmatism curve represents the meridional image plane curvature and the sagittal image plane curvature; the distortion curve represents the corresponding distortion value for different field angles. It can be seen from FIG. 6 that the optical imaging system 10 provided in the third embodiment can achieve good imaging quality.

Fourth Embodiment

Referring to FIG. 7 , the optical imaging system 10 of the fourth embodiment sequentially includes an isosceles right-angle prism L0, a diaphragm STO, a first lens L1 with positive refractive power, and a The second lens L2, the third lens L3 with negative refractive power, the fourth lens L4 with positive refractive power, the fifth lens L5 with negative refractive power, the sixth lens L6 with negative refractive power, and the infrared filter L7 .

The object side S5 of the first lens L1 is convex at the near optical axis, and the image side S6 is concave at the near optical axis; the object side S7 of the second lens L2 is convex at the near optical axis, and the image side S8 is near the optical axis. The optical axis is concave; the object side S9 of the third lens L3 is concave at the near optical axis, and the image side S10 is concave at the near optical axis; the object side S11 of the fourth lens L4 is concave at the near optical axis, and the image is concave at the near optical axis. The side S12 is convex at the near optical axis; the object side S13 of the fifth lens L5 is concave at the near optical axis, and the image side S14 is convex at the near optical axis; the object side S15 of the sixth lens L6 is at the near optical axis It is convex, and the image side S16 is concave at the near optical axis.

The reference wavelengths of the focal length, refractive index, and Abbe number in the fourth embodiment are all 587.5618 nm, and the optical imaging system 10 in the fourth embodiment satisfies the conditions in the following table.

Table 7

It should be noted that, in Table 7, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, and TTL is the object side of the first lens to The distance between the imaging surface of the optical imaging system and the optical axis, the Y radius is the radius of curvature of each surface at the optical axis.

Table 8

FIG. 8 shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the fourth embodiment, wherein the longitudinal spherical aberration curve represents the deviation of the focusing point of light of different wavelengths after passing through each lens of the optical imaging system 10 ; The astigmatism curve represents the meridional image plane curvature and the sagittal image plane curvature; the distortion curve represents the corresponding distortion value for different field angles. It can be seen from FIG. 8 that the optical imaging system 10 provided in the fourth embodiment can achieve good imaging quality.

Fifth Embodiment

Referring to FIG. 9 , the optical imaging system 10 of the fifth embodiment sequentially includes an isosceles right-angle prism L0, a diaphragm STO, a first lens L1 with a positive refractive power, a The second lens L2, the third lens L3 with negative refractive power, the fourth lens L4 with positive refractive power, the fifth lens L5 with positive refractive power, the sixth lens L6 with negative refractive power, and the infrared filter L7 .

The object side S5 of the first lens L1 is convex at the near optical axis, and the image side S6 is concave at the near optical axis; the object side S7 of the second lens L2 is convex at the near optical axis, and the image side S8 is near the optical axis. The optical axis is concave; the object side S9 of the third lens L3 is concave at the near optical axis, and the image side S10 is concave at the near optical axis; the object side S11 of the fourth lens L4 is concave at the near optical axis, and the image is concave at the near optical axis. The side S12 is convex at the near optical axis; the object side S13 of the fifth lens L5 is concave at the near optical axis, and the image side S14 is convex at the near optical axis; the object side S15 of the sixth lens L6 is at the near optical axis It is concave, and the image side S16 is concave at the near optical axis.

The object side S5 of the first lens L1 is a convex surface near the circumference, and the object side S7 of the second lens L2 is a convex surface near the circumference, and the image side S8 is a concave surface near the circumference; The object side S9 of the third lens L3 is a convex surface at the near circumference, and the image side S10 is a concave surface at the near circumference; the object side S11 of the fourth lens L4 is a concave surface at the near circumference, and the image side S12 is a convex surface at the near circumference; The object side S13 of the fifth lens L5 is concave near the circumference, and the image side S14 is convex near the circumference; the object side S15 of the sixth lens L6 is concave near the circumference, and the image side S16 is convex near the circumference.

The reference wavelengths of the focal length, refractive index, and Abbe number in the fifth embodiment are all 587.5618 nm, and the optical imaging system 10 in the fifth embodiment satisfies the conditions in the following table.

Table 9

It should be noted that, in Table 9, f is the focal length of the optical imaging system 10, FNO is the aperture number of the optical imaging system 10, FOV is the maximum field angle of the optical imaging system 10, and TTL is the object side of the first lens to The distance between the imaging surface of the optical imaging system and the optical axis, the Y radius is the radius of curvature of each surface at the optical axis.

Table 10

FIG. 10 shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system 10 of the fifth embodiment, wherein the longitudinal spherical aberration curve represents the deviation of the focal point of light of different wavelengths after passing through each lens of the optical imaging system 10 ; The astigmatism curve represents the meridional image plane curvature and the sagittal image plane curvature; the distortion curve represents the corresponding distortion value for different field angles. It can be seen from FIG. 10 that the optical imaging system 10 provided in the fifth embodiment can achieve good imaging quality.

Table 11 shows CT/TTL*10, f*ImgH/10, 0.8<tanω/P*100, D/f*100, (R7+R8 in the optical imaging systems 10 of the first to fifth embodiments )/(R7-R8), f12/f, f4/R8, v3/(v1+v2) and R9/R10 values.

Form 11

Referring to FIG. 11 , the imaging module 100 according to the embodiment of the present invention includes an optical imaging system 10 and a photosensitive element 20 , and the photosensitive element 20 is disposed on the image side of the optical imaging system 10 .

Specifically, the photosensitive element 20 can be a complementary metal oxide semiconductor (CMOS, Complementary Metal Oxide Semiconductor) image sensor or a charge-coupled device (CCD, Charge-coupled Device).

The optical imaging system 10 in the imaging module 100 of the embodiment of the present invention deflects the light transmission path in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so that the system volume originally accumulated on the longitudinal axis is reduced. Turning to the horizontal direction makes the total length of the optical imaging system have more space, which can meet the needs of light and thin, and reasonably distribute the bending force, compress the gap of each lens, make it more compact, and also make the design of the lens barrel structure more compact. It tends to be simpler, and at the same time, the total length of the optical imaging system will not increase excessively while ensuring the telephoto characteristics, and the imaging quality can also be effectively guaranteed. If it is lower than the lower limit, the optical imaging system is over-compressed, the deflection angle of the light is too large under the small air gap, and the degree of freedom is reduced, which is not conducive to the telephoto characteristic; if it is higher than the upper limit, the lenses are not compact enough, and the total length is too long. The actual assembly and production are difficult.

Please continue to refer to FIG. 12 , the electronic device 200 according to the embodiment of the present invention includes a casing 210 and an imaging module 100 , and the imaging module 100 is installed on the casing 210 for acquiring images.

The electronic device 200 of the embodiment of the present invention includes, but is not limited to, miniaturized smart phones, mobile phones, and PDAs (Personal Digital Assistants), game consoles, PCs, smart phones, automotive cameras, surveillance cameras, and tablet computers. , notebook computers, e-book readers, portable multimedia players (PMP), portable phones, video phones, digital still cameras, mobile medical devices, wearable devices and other electronic devices that support imaging.

The optical imaging system 10 in the electronic device 1000 of the above-mentioned embodiment deflects the light transmission path in the optical imaging system by adding a reflective prism, so that the light no longer propagates in a straight line, so as to convert the system volume originally stacked on the vertical axis into a horizontal one. , so that the total length of the optical imaging system has more space, which can meet the needs of light and thin, and rationally distribute the bending force, compress the gap of each lens, make it more compact, and also make the design of the lens barrel structure tend to be more It is simple, and at the same time, the total length of the optical imaging system will not increase excessively while ensuring the telephoto characteristic, and the imaging quality can also be effectively guaranteed. If it is lower than the lower limit, the optical imaging system is over-compressed, the deflection angle of the light is too large under the small air gap, and the degree of freedom is reduced, which is not conducive to the telephoto characteristic; if it is higher than the upper limit, the lenses are not compact enough and the total length is too long, The actual assembly and production are difficult.

It will be apparent to those skilled in the art that the present application is not limited to the details of the above-described exemplary embodiments, but that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Accordingly, the embodiments are to be regarded in all respects as illustrative and not restrictive, and the scope of the application is to be defined by the appended claims rather than the foregoing description, which is therefore intended to fall within the scope of the claims. All changes within the meaning and scope of the equivalents of , are included in this application.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit them. Although the present application has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present application can be Modifications or equivalent substitutions can be made without departing from the spirit and scope of the technical solutions of the present application.

Claims

An optical imaging system, characterized in that, from the object side to the image side along the optical axis, it comprises:

a prism, the prism includes an incident surface, a reflection surface and an exit surface;

a first lens with refractive power, the object side surface of the first lens is convex at the near optical axis;

a second lens having refractive power;

a third lens having refractive power;

a fourth lens with refractive power, the image side surface of the fourth lens is convex at the near optical axis;

a fifth lens with refractive power;

a sixth lens with refractive power;

The optical imaging system satisfies the following conditional formula:

1.7<CT/TTL*10<3

where CT is the sum of the air gaps on the optical axis from the image side of the first lens to the object side of the sixth lens, and TTL is the distance between the object side of the first lens and the imaging surface of the optical imaging system. distance on the optical axis.
The optical imaging system according to claim 1, further comprising a diaphragm, the diaphragm is arranged on the object side of the first lens, the refractive power of the first lens is positive, and the second lens is positive. The refractive power of the lens is positive, the refractive power of the third lens is negative, the refractive power of the fourth lens is positive, the object side of the fifth lens is concave at the near optical axis, and the image side is at the low beam. The axis is convex, the refractive power of the sixth lens is negative, and the image side surface of the sixth lens is concave at the near optical axis.
The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditional formula:

f*ImgH/10≥1.75mm 2 ;

Wherein, f is the effective focal length of the optical imaging system, and ImgH is half of the image height corresponding to the maximum angle of view of the optical imaging system.
The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditional formula:

0.8mm -1 <tanω/P*100<3mm -1 ;

Wherein, ω is half of the maximum field angle of the optical imaging system, the prism is truncated into an isosceles right triangle by the surface perpendicular to the incident surface and the reflection surface at the same time, p is the isosceles right triangle hypotenuse length.
The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditional formula:

7<D/f*100<14;

Wherein, D is the distance from the exit surface of the prism to the object side of the first lens on the optical axis, and f is the effective focal length of the optical imaging system.
The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditional formula:

0.22<(R7+R8)/(R7-R8)<3.3;

Wherein, R7 is the radius of curvature of the object side of the fourth lens at the optical axis, and R8 is the radius of curvature of the image side of the fourth lens at the optical axis.
The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditional formula:

f12/f>0.49;

Wherein, f12 is the combined focal length of the first lens and the second lens, and f is the effective focal length of the optical imaging system.
The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditional formula:

-4<f4/R8<-0.9;

Wherein, f4 is the focal length of the fourth lens, and R8 is the radius of curvature of the image side surface of the fourth lens at the optical axis.
The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditional formula:

0.15<v3/(v1+v2)<0.24;

Wherein, v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, and v3 is the Abbe number of the third lens.
The optical imaging system according to claim 1, wherein the optical imaging system satisfies the following conditional formula:

0.8<R9/R10<1.3;

Wherein, R10 is the radius of curvature of the object side of the fifth lens at the optical axis, and R11 is the radius of curvature of the image side of the fifth lens at the optical axis.
An imaging module, comprising:

The optical imaging system of any one of claims 1 to 10; and

A photosensitive element, the photosensitive element is arranged on the image side of the optical imaging system.
An electronic device, comprising:

the shell; and

The imaging module according to claim 11, wherein the imaging module is mounted on the casing.