CN218848422U - Optical imaging system - Google Patents

Abstract

The application discloses an optical imaging system, which comprises a lens barrel, a six-piece lens group and a plurality of spacing elements, wherein the six-piece lens group and the plurality of spacing elements are arranged in the lens barrel, the six-piece lens group comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are sequentially arranged from an object side to an image side along an optical axis, the second lens and the sixth lens have negative focal power, and the image side surface of the sixth lens has at least one inflection point; the plurality of spacing elements at least comprise a first spacing element which is arranged between the first lens and the second lens and is abutted against the image side surface of the first lens and a fifth spacing element which is arranged between the fifth lens and the sixth lens and is abutted against the image side surface of the fifth lens; wherein the effective focal length f2 of the second lens, the effective focal length f6 of the sixth lens, the inner diameter d1s of the object side surface of the first spacing element and the inner diameter d5s of the object side surface of the fifth spacing element satisfy: 1< (f 2 × f 6)/(d 1s × d5 s) <4.

Description

Optical imaging system

Technical Field

The application relates to the field of optical devices, in particular to a six-piece type optical imaging system.

Background

With the continuous development of scientific technology, optical imaging systems of portable devices such as mobile phones with high imaging quality are widely used, for example, wide-angle lenses and wide-angle lenses are widely used on flagships or high-end machines, and in order to improve competitiveness, wide-angle lenses with high yield and low cost are the development trend in the future.

In the six-piece optical imaging system, the first spacing element and the last spacing element are important for the overall performance of the optical imaging system, and especially, the inner diameters of the object side surfaces of the two spacing elements cause the bad parameters such as relative brightness when the inner diameters are too large, which affects the performance stability, and when the inner diameters are too small, the spacing elements can be inclined in the assembling process and cause the defocusing performance fluctuation of the optical imaging system, thereby affecting the yield and the quality.

SUMMERY OF THE UTILITY MODEL

The present application provides an optical imaging system that addresses, at least in part, at least one of the problems or other problems in the prior art.

An aspect of the present application provides an optical imaging system including a lens barrel, and a six-piece lens group and a plurality of spacing elements disposed within the lens barrel, the six-piece lens group including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in order from an object side to an image side along an optical axis, wherein the second lens and the sixth lens have negative power, and an image side surface of the sixth lens has at least one inflection point; the plurality of spacing elements at least comprise a first spacing element which is arranged between the first lens and the second lens and is abutted against the image side surface of the first lens and a fifth spacing element which is arranged between the fifth lens and the lenses and is abutted against the image side surface of the fifth lens; wherein the effective focal length f2 of the second lens, the effective focal length f6 of the sixth lens, the inner diameter d1s of the object side surface of the first spacing element and the inner diameter d5s of the object side surface of the fifth spacing element satisfy: 1< (f 2 × f 6)/(d 1s × d5 s) <4.

According to an exemplary embodiment of the present application, the plurality of spacer elements further includes a second spacer element, a third spacer element and a fourth spacer element, the second spacer element is disposed between the second lens and the third lens and abuts against an image side surface of the second lens, the third spacer element is disposed between the third lens and the fourth lens and abuts against an image side surface of the third lens, and the fourth spacer element is disposed between the fourth lens and the fifth lens and abuts against an image side surface of the fourth lens, wherein a total effective focal length f of the optical imaging system, an inner diameter dis of an object side surface of the spacer element abutting against an image side surface of a lens of which abbe number is less than 50 among the first lens to the sixth lens, satisfy: 0.5 sj/dis <2.5, wherein i =2, 3, 4 or 5.

According to an exemplary embodiment of the application, the optical imaging system further satisfies: 2< (Djm + Djm)/EPD <4.5, wherein j =1, 3, 4 or 5, wherein when j is 1, djm represents the inner diameter of the image-side face of the first spacer element and Djm represents the outer diameter of the image-side face of the first spacer element; when j is 3, djm represents the inner diameter of the image side surface of the third spacer element, and Djm represents the outer diameter of the image side surface of the third spacer element; when j is 4, djm represents the inner diameter of the image side surface of the fourth spacer element, and Djm represents the outer diameter of the image side surface of the fourth spacer element; when j is 5, djm represents the inner diameter of the image side surface of the fifth spacing element, and Djm represents the outer diameter of the image side surface of the fifth spacing element; EPD is the entrance pupil diameter of the optical imaging system.

According to an exemplary embodiment of the present application, a combined focal length f12 of the first and second lenses, a spacing EP01 of the object-side end surface of the lens barrel and the first spacing element along the optical axis, and a maximum thickness CP1 of the first spacing element satisfy: 4 were woven so as to be f12/(EP 01+ CP 1) <7.

According to an exemplary embodiment of the present application, a radius of curvature R2 of the image-side surface of the first lens, a radius of curvature R3 of the object-side surface of the second lens, and an inner diameter d1m of the image-side surface of the first spacer element satisfy: 10< (R2 + R3)/d 1m <13.

According to an exemplary embodiment of the application, the combined focal length f23 of the second and third lenses, the inner diameter D2m of the image-side surface of the second spacer element and the outer diameter D2m of the image-side surface of the second spacer element satisfy: 6< | f23 |/(D2 m + D2 m) <12.

According to an exemplary embodiment of the present application, a radius of curvature R6 of an image-side surface of the third lens, a radius of curvature R7 of an object-side surface of the fourth lens, an interval EP12 of the first and second spacing elements along the optical axis, and an inner diameter d3s of the object-side surface of the third spacing element satisfy: 12< (R6 XR 7)/(EP 12 Xd 3 s) <28.

According to an exemplary embodiment of the application, the combined focal length f45 of the fourth lens and the fifth lens, the inner diameter d4s of the object side surface of the fourth spacer element and the inner diameter d4m of the image side surface of the fourth spacer element satisfy: 0.2 sj & lt f45/(d 4s + d4 m) <3.

According to an exemplary embodiment of the application, the radius of curvature R8 of the image-side surface of the fourth lens, the spacing EP34 of the third and fourth spacing elements along the optical axis, the maximum thickness CP4 of the fourth spacing element and the spacing EP45 of the fourth and fifth spacing elements along the optical axis satisfy: 1.5< | R8 |/(EP 34+ CP4+ EP 45) <72.

According to an exemplary embodiment of the present application, an on-axis distance TD between an object-side surface of the first lens and an image-side surface of the sixth lens, an entrance pupil diameter EPD of the optical imaging system, an inner diameter d0s of an object-side end surface of the lens barrel, and an interval EP23 along the optical axis of the second spacer element and the third spacer element satisfy: 4< (TD × EPD)/(d 0s × EP 23) <7.

According to an exemplary embodiment of the application, the effective focal length f3 of the third lens, the central thickness CT3 of the third lens on the optical axis, the inner diameter d2s of the object side surface of the second spacer element and the inner diameter d3m of the image side surface of the third spacer element satisfy: 0.5< (f 3 × CT 3)/(d 2s × d3 m) <1.5.

According to an exemplary embodiment of the application, the effective focal length f4 of the fourth lens, the effective focal length f5 of the fifth lens and the inner diameter d5m of the image side surface of the fifth spacer element satisfy: 2< | f4-f5|/d5m <4.

According to an exemplary embodiment of the present application, at least three lenses of the first to fourth lenses are meniscus-shaped in a paraxial region.

According to an exemplary embodiment of the present application, a radius of curvature R1 of the object-side surface of the first lens and a radius of curvature R4 of the image-side surface of the second lens satisfy: r4> R1>0.

The first spacing element and the last spacing element are important for the overall performance of the optical imaging system, if the inner diameter of the first spacing element and the last spacing element is too large, the poor performance of parameters such as relative brightness can be caused, if the inner diameter of the first spacing element and the last spacing element is too small, the defocusing performance of the optical imaging system can fluctuate, and the yield and the quality are affected.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, made with reference to the accompanying drawings in which:

FIG. 1 shows a schematic structural diagram of an optical imaging system according to the present application;

fig. 2 shows a schematic configuration of an optical imaging system according to example 1 of a first embodiment of the present application;

fig. 3 shows a schematic configuration diagram of an optical imaging system according to example 2 of the first embodiment of the present application;

fig. 4 shows a schematic configuration diagram of an optical imaging system according to example 3 of the first embodiment of the present application;

fig. 5A to 5C show an on-axis chromatic aberration curve, an astigmatism curve, and a distortion curve, respectively, of an optical imaging system according to a first embodiment of the present application;

fig. 6 shows a schematic configuration of an optical imaging system according to example 1 of a second embodiment of the present application;

fig. 7 shows a schematic configuration diagram of an optical imaging system according to example 2 of a second embodiment of the present application;

fig. 8 shows a schematic configuration diagram of an optical imaging system according to example 3 of a second embodiment of the present application;

fig. 9A to 9C show an on-axis chromatic aberration curve, an astigmatism curve, and a distortion curve, respectively, of an optical imaging system according to a second embodiment of the present application;

fig. 10 shows a schematic configuration diagram of an optical imaging system according to example 1 of a third embodiment of the present application;

fig. 11 shows a schematic configuration diagram of an optical imaging system according to example 2 of a third embodiment of the present application;

fig. 12 shows a schematic configuration diagram of an optical imaging system according to example 3 of a third embodiment of the present application; and

fig. 13A to 13C show an on-axis chromatic aberration curve, an astigmatism curve, and a distortion curve, respectively, of an optical imaging system according to a third embodiment of the present application.

Detailed Description

For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that the detailed description is merely illustrative of exemplary embodiments of the present application and does not limit the scope of the present application in any way. Like reference numerals refer to like elements throughout the specification.

It should be noted that in this specification the expressions first, second, third etc. are only used to distinguish one feature from another, and do not represent any limitation on the features. Thus, the first lens discussed below may also be referred to as the second lens or the third lens without departing from the teachings of the present application.

In the drawings, the thickness, size, and shape of the lens have been slightly exaggerated for convenience of explanation. In particular, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shape of the spherical surface or the aspherical surface is not limited to the shape of the spherical surface or the aspherical surface shown in the drawings. The figures are purely diagrammatic and not drawn to scale.

Herein, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the convex position is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is called the object side surface of the lens, and the surface of each lens closest to the imaging surface is called the image side surface of the lens.

It will be further understood that the terms "comprises," "comprising," "has," "having," "includes" and/or "including," when used in this specification, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof. Furthermore, when describing embodiments of the present application, the use of "may" mean "one or more embodiments of the present application. Also, the term "exemplary" is intended to refer to an example or illustration.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

The following provides a detailed description of the features, principles, and other aspects of the present application.

An optical imaging system according to an exemplary embodiment of the present application may include a lens barrel and a six-piece lens group disposed within the lens barrel, the six-piece lens group including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens, and the six lenses being arranged in order from an object side to an image side along an optical axis. Any adjacent two lenses among the first to sixth lenses may have an air space therebetween. The second lens and the sixth lens have negative focal power, and the image side surface of the sixth lens has at least one inflection point. The effective diameter edge of the image side surface of the sixth lens trends to the right, the bearing position of the fifth lens is limited by the lens barrel structure, and the bearing structure of the fifth lens and the bearing structure of the sixth lens can be ensured to be stable by arranging an inflection point on the bearing structure of the image side surface of the sixth lens and the effective diameter edge.

The optical imaging system can further comprise a plurality of spacing elements arranged in the lens barrel, wherein the plurality of spacing elements at least comprise a first spacing element and a fifth spacing element, the first spacing element is arranged between the first lens and the second lens and is abutted against the image side surface of the first lens, and the fifth spacing element is arranged between the fifth lens and the sixth lens and is abutted against the image side surface of the fifth lens. The inner diameters of the object-side surfaces of the first spacer element and the fifth spacer element are important for the overall performance of the optical imaging system, if the inner diameters are too large, poor parameters such as relative brightness can be caused, if the inner diameters are too small, the spacer elements can be inclined in the assembling process and the defocusing performance of the optical imaging system can fluctuate, so that the yield of mass production is affected, and the quality fluctuation of the optical imaging system generated in the case in use can also risk, so that the inner diameters of the object-side surfaces of the first spacer element and the fifth spacer element need to be controlled to avoid the problems. In an example, an effective focal length f2 of the second lens, an effective focal length f6 of the sixth lens, an inner diameter d1s of the object side surface of the first spacer element, and an inner diameter d5s of the object side surface of the fifth spacer element may satisfy: 1< (f 2 × f 6)/(d 1s × d5 s) <4. By controlling the mutual relation among the effective focal length of the second lens, the effective focal length of the sixth lens, the inner diameter of the object side surface of the first spacing element and the inner diameter of the object side surface of the fifth spacing element, the inner diameters of the object side surfaces of the first spacing element and the fifth spacing element are limited in a reasonable interval, the tolerance range of sensitive element accumulation is favorably regulated, and the performance stability, yield and quality of the optical imaging system are improved.

The plurality of spacing elements may further include a second spacing element disposed between the second lens and the third lens and abutting against the image-side surface of the second lens, a third spacing element disposed between the third lens and the fourth lens and abutting against the image-side surface of the third lens, and a fourth spacing element disposed between the fourth lens and the fifth lens and abutting against the image-side surface of the fourth lens. The reasonable use of the spacing element can effectively avoid the risk of stray light, reduce the interference to the image quality and further improve the imaging quality of the optical imaging system. These spacing elements will be described in detail below.

In an exemplary embodiment, the lens barrel has an object-side end surface and an image-side end surface, and an opening diameter of the object-side end surface is smaller than an opening diameter of the image-side end surface. Because the optical imaging system needs and considers that the matching state in the camera module when the optical imaging system is used as an assembly part is that the image side is fixed and the object side is suspended, the structure that the object side is small, the image side is large and the middle is in gradient transition is set, and the extrusion deformation of the optical imaging system after the image side is stressed can be reduced as much as possible on the premise of ensuring the wall thickness of the lens cone.

In an exemplary embodiment, the total effective focal length f of the optical imaging system, the inner diameter dis of the object side surface of the spacer element abutting the image side surface of the lens having an abbe number less than 50 among the first lens to the sixth lens, satisfies: 0.5< -f/dis <2.5, wherein i =2, 3, 4 or 5. The first lens to the sixth lens are all injection molded lenses, because the injection molded lenses have the characteristic of one cavity and multiple cavities, the performance of the optical imaging system is poor due to the fact that the fine size difference among the cavity lenses affects the performance of the lenses, and the inner diameter of the object side surface of the spacing element at the image side surface of the lens with the Abbe number smaller than 50 can be limited within a reasonable interval by controlling the conditional expression, so that the poor performance of the optical imaging system caused by the performance difference of the lenses can be prevented to a certain extent, the optical performance of the optical imaging system is ensured, and various available cavity lenses can be produced.

In an exemplary embodiment, the optical imaging system further satisfies: 2< (Djm + Djm)/EPD <4.5, wherein j =1, 3, 4 or 5, wherein j is the number of the lens having positive power among the first to sixth lenses, and when j takes 1, djm represents the inner diameter of the image-side surface of the first spacing element, and Djm represents the outer diameter of the image-side surface of the first spacing element; when j is 3, djm represents the inner diameter of the image side surface of the third spacer element, and Djm represents the outer diameter of the image side surface of the third spacer element; when j is 4, djm represents the inner diameter of the image side surface of the fourth spacer element, and Djm represents the outer diameter of the image side surface of the fourth spacer element; when j is 5, djm represents the inner diameter of the image side surface of the fifth spacing element, and Djm represents the outer diameter of the image side surface of the fifth spacing element; EPD is the entrance pupil diameter of the optical imaging system. The performance of the optical imaging system can be directly influenced by the position of the spacing element in the internal space of the optical imaging system, and the change of the optical performance caused by the problems of light interception and the like can be reduced by limiting the inner diameter and the outer diameter of the image side surface of the spacing element at the image side surface of the lens with positive focal power in a reasonable interval, so that the quality of the optical imaging system is improved.

In an exemplary embodiment, a combined focal length f12 of the first lens and the second lens, a spacing EP01 of the object-side end surface of the lens barrel and the first spacing element along the optical axis, and a maximum thickness CP1 of the first spacing element satisfy: 4 were woven so as to be f12/(EP 01+ CP 1) <7. The gap between the first lens and the second lens on the optical axis is a first air gap and is most sensitive to defocusing performance, and the gap between the first lens and the second lens on the optical axis is determined by the first spacing element.

In an exemplary embodiment, the radius of curvature R2 of the image-side surface of the first lens, the radius of curvature R3 of the object-side surface of the second lens, and the inner diameter d1m of the image-side surface of the first spacing element satisfy: 10< (R2 + R3)/d 1m <13. Compared with other lenses or other spacing elements, the first two lenses and the first spacing element have larger influence on the performance of the optical imaging system, and the problem of reduction of product yield caused by lens size fluctuation can be effectively avoided by controlling the mutual relation among the curvature radius of the image side surface of the first lens, the curvature radius of the object side surface of the second lens and the inner diameter of the image side surface of the first spacing element, and the reliability of the optical imaging system is improved.

In an exemplary embodiment, at least three of the first through fourth lenses are meniscus-shaped in a paraxial region. The effective diameter shape of the paraxial region is obtained by calculation of the optical system, the deformation trend of the lens is single when the lens is loaded in the lens barrel due to the synchronous shape, and the effect of fine adjustment on the performance of the optical imaging system can be achieved by controlling the deformation quantity of part of the lens in the actual assembling and reliability verification processes, so that the performance and yield of the optical imaging system are improved.

In an exemplary embodiment, the radius of curvature R1 of the object-side surface of the first lens and the radius of curvature R4 of the image-side surface of the second lens satisfy: r4> R1>0. The optical imaging system is a middle diaphragm lens, the diaphragm is positioned between the first lens and the second lens, and the curvature radius of the object side surface of the first lens is smaller than that of the image side surface of the second lens, so that the optical imaging system can be applied to lenses with large field angles, such as wide-angle lenses.

In an exemplary embodiment, the combined focal length f23 of the second and third lenses, the inner diameter D2m of the image-side surface of the second spacer element, and the outer diameter D2m of the image-side surface of the second spacer element satisfy: 6< | f23 |/(D2 m + D2 m) <12. The second spacing element is close to the position of the diaphragm, the size of the second spacing element can directly influence important parameters of the optical imaging system, such as relative F number Fno, focal length, clear aperture, performance and the like, the position of the second spacing element is also a gap sensitive to the defocusing performance of the optical imaging system, the size of the second spacing element can be limited in a reasonable interval by controlling the mutual relation between the combined focal length of the second lens and the third lens and the inner and outer diameters of the image side surface of the second spacing element, and the quality and the yield of the optical imaging system are effectively controlled.

In an exemplary embodiment, a radius of curvature R6 of an image-side surface of the third lens, a radius of curvature R7 of an object-side surface of the fourth lens, a distance EP12 of the first spacer element and the second spacer element along the optical axis, and an inner diameter d3s of the object-side surface of the third spacer element satisfy: 12< (R6 × R7)/(EP 12 × d3 s) <28. The curvature radius of the image side surface of the third lens, the curvature radius of the object side surface of the fourth lens, the mutual relation between the interval of the first spacing element and the second spacing element along the optical axis and the inner diameter of the object side surface of the third spacing element are reasonably controlled, the distance between the first lens and the second lens on the optical axis is in a reasonable interval, meanwhile, the inner diameter of the object side surface of the third spacing element is controlled to be in a reasonable range, so that the optical performance fluctuation is limited to a certain extent, and the quality of an optical imaging system is improved.

In an exemplary embodiment, the combined focal length f45 of the fourth lens and the fifth lens, the inner diameter d4s of the object side face of the fourth spacer element and the inner diameter d4m of the image side face of the fourth spacer element satisfy: 0.2 sj & lt f45/(d 4s + d4 m) <3. In the example, 0.4-woven fabric f 45/(d 4s + d4 m) <2.1. The problem of internal reflection of stray light can exist when light rays in the optical imaging system pass through the fourth spacing element, the mutual relation between the combined focal length of the fourth lens and the fifth lens and the inner diameters of the object side surface and the image side surface of the fourth spacing element is controlled, so that the inner diameters of the object side surface and the image side surface of the fourth spacing element are limited in a reasonable interval, the reflection direction of the stray light is effectively controlled, the stray light deviates from an imaging surface, and the hidden danger of the stray light can be eliminated when the optical imaging system is applied to a terminal.

In an exemplary embodiment, a radius of curvature R8 of the image-side surface of the fourth lens, a spacing EP34 of the third and fourth spacing elements along the optical axis, a maximum thickness CP4 of the fourth spacing element, and a spacing EP45 of the fourth and fifth spacing elements along the optical axis satisfy: 1.5< | R8 |/(EP 34+ CP4+ EP 45) <72. Compared with the first three lenses, the size of the fourth lens and the fifth lens has little influence on the overall performance of the optical imaging system, and the distance between the fourth lens and the fifth lens on the optical axis is within a reasonable interval by controlling the mutual relation among the curvature radius of the image side surface of the fourth lens, the interval between the third spacing element and the fourth spacing element along the optical axis, the maximum thickness of the fourth spacing element and the interval between the fourth spacing element and the fifth spacing element along the optical axis, so that the defocusing performance of the optical imaging system is finely adjusted, and the yield and the quality of the optical imaging system are improved.

In an exemplary embodiment, an on-axis distance TD from an object-side surface of the first lens to an image-side surface of the sixth lens, an entrance pupil diameter EPD of the optical imaging system, an inner diameter d0s of an object-side end surface of the lens barrel, and an interval EP23 along the optical axis of the second spacer element and the third spacer element satisfy: 4< (TD × EPD)/(d 0s × EP 23) <7. Under extreme environments or external force conditions such as reliability verification, the edge thickness of the third lens has a limiting effect on the deformation of the lens, and the phenomenon can simultaneously affect a plurality of performance sensitive sizes including the second air gap and the third air gap, and by controlling the axial distance from the object side surface of the first lens to the image side surface of the sixth lens, the entrance pupil diameter of the optical imaging system, the inner diameter of the object side end surface of the lens barrel and the interval between the second spacing element and the third spacing element along the optical axis, the edge thickness of the third lens, the size of the second air gap and the size of the third air gap can be limited, so that the performance of the optical imaging system can be limited, and the yield and the quality of the optical imaging system can be improved.

In an exemplary embodiment, the effective focal length f3 of the third lens, the central thickness CT3 of the third lens on the optical axis, the inner diameter d2s of the object-side surface of the second spacer element and the inner diameter d3m of the image-side surface of the third spacer element satisfy: 0.5< (f 3 × CT 3)/(d 2s × d3 m) <1.5. In the example, 0.55< (f 3 × CT 3)/(d 2s × d3 m) <1.10. The problem of internal stray light reflection can exist when light rays in the optical imaging system pass through the second spacing element, the effective focal length of the third lens, the center thickness of the third lens on the optical axis and the mutual relation between the inner diameter of the object side surface of the second spacing element and the inner diameter of the image side surface of the third spacing element are controlled, so that the inner diameters of the second spacing element and the third spacing element are limited in a reasonable interval, the reflection direction of the stray light is effectively controlled, and the stray light deviates from an imaging surface, and the hidden danger of the stray light can be eliminated when the optical imaging system is applied to a terminal.

In an exemplary embodiment, the effective focal length f4 of the fourth lens, the effective focal length f5 of the fifth lens, and the inner diameter d5m of the image-side surface of the fifth spacing element satisfy: 2< | f4-f5|/d5m <4. The fifth spacing element is the spacing element closest to the image side face in the optical imaging system, and is also the last light shielding sheet in the component integrally matched with the optical system, the external diameter size control needs to be tightened while the supplied material size of the fifth spacing element is controlled, so that the spacing element is prevented from translating perpendicular to the optical axis in the actual assembly process due to poor external diameter size, and the problem of asymmetry of relative brightness or other optical parameters caused by translation of the fifth spacing element is avoided.

The optical imaging system according to the above-described embodiment of the present application may employ six lenses and a plurality of spacer elements, such as the above six lenses and five spacer elements. Through the optical parameters of each lens and each spacing element which are reasonably distributed, the defocusing performance of the optical imaging system can be finely adjusted, the risk of stray light is reduced, and the performance stability, the quality and the yield of the optical imaging system are improved.

In the embodiment of the present application, at least one of the mirror surfaces of each of the first to sixth lenses is an aspherical mirror surface. The aspheric lens is characterized in that: the curvature varies continuously from the center of the lens to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has better curvature radius characteristics, and has advantages of improving distortion aberration and improving astigmatic aberration. After the aspheric lens is adopted, the aberration generated in imaging can be eliminated as much as possible, and the imaging quality is further improved.

However, it will be appreciated by those skilled in the art that the number of lenses and spacing elements making up the optical imaging system may be varied to achieve the various results and advantages described in the present specification without departing from the claimed technology. For example, although six lenses and five spacer elements are exemplified in the embodiment, the optical imaging system is not limited to include six lenses and five spacer elements. The optical imaging system may also include other numbers of lenses or spacing elements, if desired.

Specific examples of the optical imaging system that can be applied to the above-described embodiments are further described below with reference to the drawings.

First embodiment

An optical imaging system according to a first embodiment of the present application is described below with reference to fig. 2 to 5C. Fig. 2 shows a schematic configuration diagram of an optical imaging system 110 according to example 1 of the first embodiment of the present application; fig. 3 shows a schematic structural diagram of an optical imaging system 120 according to example 2 of the first embodiment of the present application; fig. 4 shows a schematic structural diagram of an optical imaging system 130 according to example 3 of the first embodiment of the present application.

As shown in fig. 2 to 4, each of the optical imaging systems 110, 120, 130 includes a lens barrel P0, and a six-piece lens group and a plurality of spacing elements disposed in the lens barrel P0, the six-piece lens group includes, in order from an object side to an image side: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, and a sixth lens E6. The stop STO can be disposed between the first lens E1 and the second lens E2 according to actual needs. The plurality of spacing elements comprises: a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4 and a fifth spacer element P5. The spacing elements P1-P5 can block the entry of external redundant light, so that the lens and the lens barrel P0 are better supported, and the structural stability of the optical imaging system is enhanced.

The first lens element E1 has positive refractive power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element E2 has negative power, and the object-side surface S3 is convex and the image-side surface S4 is concave. The third lens element E3 has positive refractive power, and has a convex object-side surface S5 and a convex image-side surface S6. The fourth lens element E4 has positive power, and has a concave object-side surface S7 and a convex image-side surface S8. The fifth lens element E5 has a negative refractive power, and has a concave object-side surface S9 and a concave image-side surface S10. The sixth lens element E6 has negative power, and has a convex object-side surface S11 and a concave image-side surface S12. The filter has an object side surface S13 (not shown) and an image side surface S14 (not shown). The light from the object passes through the respective surfaces S1 to S14 in order and is finally imaged on the imaging surface S15 (not shown in the figure).

Table 1 shows a basic parameter table of the optical imaging system of the first embodiment in which the units of the radius of curvature, the thickness/distance, and the focal length are all millimeters (mm).

TABLE 1

In this embodiment, the total effective focal length f of the optical imaging system is 4.03mm, the on-axis distance TD from the object-side surface of the first lens to the image-side surface of the sixth lens is 3.903mm, the half ImgH of the diagonal length of the effective pixel region on the imaging plane is 3.26mm, and the entrance pupil diameter EPD of the optical imaging system is 2.43mm.

In the first embodiment, the object-side surface and the image-side surface of any one of the first lens E1 to the sixth lens E6 are aspheric surfaces, and the surface shape x of each aspheric lens can be defined by, but is not limited to, the following aspheric surface formula:

wherein x is a non-sphereWhen the surface is at the position with the height of h along the optical axis direction, the distance from the vertex of the aspheric surface is higher; c is the paraxial curvature of the aspheric surface, c =1/R (i.e., paraxial curvature c is the reciprocal of the radius of curvature R in table 1 above); k is a conic coefficient; ai is the correction coefficient of the i-th order of the aspherical surface. Table 2 shows the high-order coefficient A that can be used for each of the aspherical mirror surfaces S1 to S12 in the first embodiment ₄ 、A ₆ 、A ₈ 、A ₁₀ 、A ₁₂ 、A ₁₄ 、A ₁₆ 、A ₁₈ And A ₂₀ 。

Flour mark

A4

A6

A8

A10

A12

A14

A16

A18

A20

S1

-1.4446E-02

2.1631E-03

-4.3394E-02

1.1465E-01

-1.9483E-01

1.9896E-01

-1.2275E-01

4.1837E-02

-6.1694E-03

S2

-2.6043E-02

2.5803E-02

-1.2400E-02

-2.7859E-02

8.2129E-02

-1.1370E-01

8.8685E-02

-3.7191E-02

6.4632E-03

S3

-5.0457E-02

1.2654E-01

-4.6870E-01

1.6128E+00

-3.5043E+00

4.6992E+00

-3.7804E+00

1.6724E+00

-3.1239E-01

S4

7.1776E-02

-1.5735E-01

9.3944E-01

-3.5671E+00

8.9745E+00

-1.4355E+01

1.4100E+01

-7.7507E+00

1.8389E+00

S5

-5.7801E-02

7.2962E-03

-2.1394E-01

7.6340E-01

-1.6083E+00

1.8784E+00

-1.0368E+00

7.4490E-02

1.1718E-01

S6

-1.0468E-02

-3.3125E-01

1.4041E+00

-4.0273E+00

7.2657E+00

-8.2759E+00

5.7992E+00

-2.2839E+00

3.8770E-01

S7

-7.3642E-03

-2.9040E-01

1.2114E+00

-2.7735E+00

3.5942E+00

-2.7274E+00

1.2182E+00

-3.0150E-01

3.2375E-02

S8

-6.1469E-02

3.1034E-01

-2.9836E-01

-1.8150E-01

5.8510E-01

-4.8083E-01

1.9264E-01

-3.8911E-02

3.1850E-03

S9

-4.7542E-02

3.5319E-01

-8.8059E-01

1.0202E+00

-6.9716E-01

2.9786E-01

-7.8019E-02

1.1434E-02

-7.1649E-04

S10

2.6009E-01

-4.7940E-01

4.1930E-01

-2.3756E-01

9.1287E-02

-2.3669E-02

3.9681E-03

-3.8805E-04

1.6782E-05

S11

8.2052E-02

-2.6031E-01

1.9138E-01

-7.3437E-02

1.6483E-02

-2.0820E-03

1.1303E-04

2.3210E-06

-3.9513E-07

S12

-6.7904E-02

-2.2919E-02

2.1191E-02

-8.3376E-03

2.1888E-03

-3.7010E-04

3.4142E-05

-1.0785E-06

-2.6043E-08

TABLE 2

The optical imaging systems 110, 120 and 130 in examples 1, 2 and 3 of the first embodiment are different in the structural sizes of the lens barrel and the spacer included therein. Tables 3-1 to 3-2 show some basic parameters of the lens barrels and the spacing elements of the optical imaging systems 110, 120 and 130 of the first embodiment, such as D1s, D1m, D2s, D2m, D3s, D3m, D4s, D4m, D5s, D5m, D0s, EP01, CP1, EP12, EP23, EP34, CP4, EP45, etc., some of the basic parameters shown in tables 3-1 to 3-2 are measured according to the labeling method shown in fig. 1, and the units of the basic parameters shown in tables 3-1 to 3-2 are all millimeters (mm).

Examples/parameters	d1s	d1m	D1m	d2s	d2m	D2m	d3s	d3m	D3m	d4s	d4m	D4m
													1-1	2.144	2.144	3.785	1.902	1.902	3.945	2.442	2.442	4.440	3.401	3.401	5.032
1-2	2.155	2.155	3.785	1.911	1.911	3.945	2.424	2.424	4.440	3.335	3.335	5.032
													1-3	2.113	2.113	3.785	1.936	1.936	3.945	2.455	2.455	4.440	3.407	3.407	5.032

TABLE 3-1

Examples/parameters	d5s	d5m	D5m	d0s	EP01	CP1	EP12	EP23	EP34	CP4	EP45
												1-1	4.294	4.294	5.281	4.013	0.807	0.032	0.579	0.562	0.611	0.032	0.455
1-2	4.264	4.264	5.281	4.013	0.796	0.032	0.598	0.529	0.619	0.032	0.458
												1-3	4.321	4.321	5.281	4.013	0.843	0.032	0.576	0.547	0.595	0.032	0.466

TABLE 3-2

Fig. 5A shows on-axis chromatic aberration curves of the optical imaging systems 110, 120, and 130 of the first embodiment, which represent the deviation of the convergent focal points of light rays of different wavelengths after passing through the optical imaging systems 110, 120, and 130. Fig. 5B shows astigmatism curves of the optical imaging systems 110, 120, and 130 of the first embodiment, which represent meridional field curvature and sagittal field curvature corresponding to different image heights. Fig. 5C shows distortion curves of the optical imaging systems 110, 120, and 130 of the first embodiment, which represent distortion magnitude values corresponding to different image heights. As can be seen from fig. 5A to 5C, the optical imaging systems 110, 120, and 130 according to the first embodiment can achieve good imaging quality.

Second embodiment

An optical imaging system according to a second embodiment of the present application is described below with reference to fig. 6 to 9C. Fig. 6 shows a schematic structural diagram of an optical imaging system 210 according to example 1 of a second embodiment of the present application; fig. 7 shows a schematic configuration of an optical imaging system 220 according to example 2 of a second embodiment of the present application; fig. 8 shows a schematic structural diagram of an optical imaging system 230 according to example 3 of the second embodiment of the present application.

As shown in fig. 6 to 8, each of the optical imaging systems 210, 220, and 230 includes a lens barrel P0, and a six-piece lens group and a plurality of spacing elements disposed in the lens barrel P0, the six-piece lens group includes, in order from an object side to an image side: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, and a sixth lens E6. The stop STO can be disposed between the first lens E1 and the second lens E2 according to actual needs. The plurality of spacing elements comprises: a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4 and a fifth spacer element P5. The spacing elements P1-P5 can block the entry of external redundant light, so that the lens and the lens barrel P0 are better supported, and the structural stability of the optical imaging system is enhanced.

The first lens element E1 has positive refractive power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element E2 has a negative power, and the object-side surface S3 is convex and the image-side surface S4 is concave. The third lens element E3 has positive refractive power, and has a concave object-side surface S5 and a convex image-side surface S6. The fourth lens element E4 has a negative refractive power, and has a concave object-side surface S7 and a convex image-side surface S8. The fifth lens element E5 has positive refractive power, and has a convex object-side surface S9 and a convex image-side surface S10. The sixth lens element E6 has negative refractive power, and has a concave object-side surface S11 and a concave image-side surface S12. The filter has an object side surface S13 (not shown) and an image side surface S14 (not shown). The light from the object passes through the respective surfaces S1 to S14 in order and is finally imaged on the imaging surface S15 (not shown in the figure).

Table 4 shows a basic parameter table of the optical imaging system of the second embodiment in which the units of the radius of curvature, the thickness/distance, and the focal length are millimeters (mm).

TABLE 4

In this embodiment, the total effective focal length f of the optical imaging system is 4.45mm, the on-axis distance TD from the object side surface of the first lens to the image side surface of the sixth lens is 4.471mm, the half ImgH of the diagonal length of the effective pixel area on the imaging plane is 3.50mm, and the entrance pupil diameter EPD of the optical imaging system is 2.83mm.

In the second embodiment, both the object-side surface and the image-side surface of any one of the first lens element E1 to the sixth lens element E6 are aspheric. Tables 5-1 to 5-2 show the coefficients A of the high-order terms which can be used for the aspherical mirror surfaces S1 to S12 in the second embodiment ₄ 、A ₆ 、A ₈ 、A ₁₀ 、A ₁₂ 、A ₁₄ 、A ₁₆ 、A ₁₈ 、A ₂₀ 、A ₂₂ 、A ₂₄ 、A ₂₆ 、A ₂₈ And A ₃₀ 。

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

1.1481E-03

1.2038E-02

-3.8694E-02

7.5538E-02

-8.9789E-02

6.5789E-02

-2.9195E-02

S2

-1.1562E-02

1.9895E-03

2.0727E-02

-5.4752E-02

7.3582E-02

-6.0464E-02

2.9936E-02

S3

-6.6665E-02

4.2247E-01

-3.8299E+00

2.3298E+01

-9.3882E+01

2.6116E+02

-5.1505E+02

S4

6.6755E-03

-2.4338E-02

3.1401E-01

-1.1825E+00

2.6585E+00

-3.6510E+00

3.0148E+00

S5

-4.7509E-02

3.4355E-01

-3.1867E+00

1.5424E+01

-4.2894E+01

5.6357E+01

3.5811E+01

S6

1.5100E-02

-6.6389E-01

5.0835E+00

-2.6090E+01

8.9877E+01

-2.1482E+02

3.6499E+02

S7

-2.5115E-02

3.3681E-01

-3.3534E+00

1.4872E+01

-4.1170E+01

7.8093E+01

-1.0530E+02

S8

2.6444E-02

-1.8329E-01

-9.1499E-02

1.0482E+00

-2.3817E+00

3.2279E+00

-2.9489E+00

S9

1.3879E-01

-2.1826E-01

3.0662E-01

-5.0723E-01

6.6353E-01

-6.1912E-01

4.0950E-01

S10

3.2555E-01

-3.4541E-01

4.3196E-01

-5.5327E-01

5.3430E-01

-3.6538E-01

1.7701E-01

S11

7.6615E-02

-2.3561E-01

2.3247E-01

-1.3774E-01

5.2235E-02

-1.2543E-02

1.8401E-03

S12

-7.0996E-02

3.7768E-03

1.7255E-02

-1.6081E-02

1.0995E-02

-6.5510E-03

3.0895E-03

TABLE 5-1

Flour mark

A18

A20

A22

A24

A26

A28

A30

S1

7.1865E-03

-7.6086E-04

0.0000E+00

0.0000E+00

0.0000E+00

0.0000E+00

0.0000E+00

S2

-8.1976E-03

9.4860E-04

0.0000E+00

0.0000E+00

0.0000E+00

0.0000E+00

0.0000E+00

S3

7.3031E+02

-7.4652E+02

5.4497E+02

-2.7699E+02

9.3085E+01

-1.8586E+01

1.6692E+00

S4

-1.3746E+00

2.6717E-01

0.0000E+00

0.0000E+00

0.0000E+00

0.0000E+00

0.0000E+00

S5

-2.9981E+02

6.1284E+02

-7.1754E+02

5.3072E+02

-2.4573E+02

6.5270E+01

-7.6077E+00

S6

-4.4678E+02

3.9507E+02

-2.4998E+02

1.1032E+02

-3.2228E+01

5.5978E+00

-4.3724E-01

S7

1.0253E+02

-7.2273E+01

3.6507E+01

-1.2874E+01

3.0088E+00

-4.1868E-01

2.6260E-02

S8

1.8666E+00

-8.0832E-01

2.2613E-01

-3.4426E-02

6.8681E-04

5.9579E-04

-6.5210E-05

S9

-1.9195E-01

6.3261E-02

-1.4355E-02

2.1493E-03

-1.9517E-04

8.9134E-06

-1.1113E-07

S10

-6.0743E-02

1.4592E-02

-2.3810E-03

2.4738E-04

-1.4043E-05

2.3155E-07

9.0483E-09

S11

-1.5063E-04

5.2783E-06

0.0000E+00

0.0000E+00

0.0000E+00

0.0000E+00

0.0000E+00

S12

-1.0617E-03

2.5741E-04

-4.3301E-05

4.9344E-06

-3.6297E-07

1.5541E-08

-2.9409E-10

TABLE 5-2

The optical imaging systems 210, 220, and 230 in examples 1, 2, and 3 of the second embodiment are different in the structural sizes of the lens barrel and the spacer included therein. Tables 6-1 to 6-2 show some basic parameters of the lens barrels and the spacing elements of the optical imaging systems 210, 220 and 230 of the second embodiment, such as D1s, D1m, D2s, D2m, D3s, D3m, D4s, D4m, D5s, D5m, D0s, EP01, CP1, EP12, EP23, EP34, CP4, EP45, etc., some of the basic parameters shown in tables 6-1 to 6-2 are measured according to the labeling method shown in fig. 1, and the units of the basic parameters shown in tables 6-1 to 6-2 are all millimeters (mm).

TABLE 6-1

Examples/parameters	d5s	d5m	D5m	d0s	EP01	CP1	EP12	EP23	EP34	CP4	EP45
												2-1	4.815	4.678	7.021	3.995	1.069	0.019	0.600	0.476	0.624	0.019	0.619
2-2	4.814	4.677	7.021	3.995	1.054	0.019	0.610	0.470	0.623	0.019	0.627
												2-3	4.834	4.695	7.021	3.995	1.088	0.019	0.582	0.490	0.635	0.019	0.601

TABLE 6-2

Fig. 9A shows on-axis chromatic aberration curves of the optical imaging systems 210, 220, and 230 of the second embodiment, which represent the deviation of the convergent focal points of light rays of different wavelengths after passing through the optical imaging systems 210, 220, and 230. Fig. 9B shows astigmatism curves of the optical imaging systems 210, 220, and 230 of the second embodiment, which represent meridional field curvature and sagittal field curvature corresponding to different image heights. Fig. 9C shows distortion curves of the optical imaging systems 210, 220, and 230 of the second embodiment, which represent distortion magnitude values corresponding to different image heights. As can be seen from fig. 9A to 9C, the optical imaging systems 210, 220, and 230 according to the second embodiment can achieve good imaging quality.

Third embodiment

An optical imaging system according to a third embodiment of the present application is described below with reference to fig. 10 to 13C. Fig. 10 shows a schematic configuration of an optical imaging system 310 according to example 1 of a third embodiment of the present application; fig. 11 shows a schematic configuration of an optical imaging system 320 according to example 2 of a third embodiment of the present application; fig. 12 shows a schematic configuration of an optical imaging system 330 according to example 3 of a third embodiment of the present application.

As shown in fig. 10 to 12, each of the optical imaging systems 210, 220, 230 includes a lens barrel P0, and a six-piece lens group and a plurality of spacing elements disposed in the lens barrel P0, the six-piece lens group includes, in order from an object side to an image side: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, and a sixth lens E6. The stop STO can be disposed between the first lens E1 and the second lens E2 according to actual needs. The plurality of spacing elements comprises: a first spacing element P1, a second spacing element P2, a third spacing element P3, a fourth spacing element P4 and a fifth spacing element P5. The spacing elements P1-P5 can block the entry of external redundant light, so that the lens and the lens cone P0 are better supported, and the structural stability of the optical imaging system is enhanced.

The first lens element E1 has positive refractive power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element E2 has negative power, and the object-side surface S3 is convex and the image-side surface S4 is concave. The third lens element E3 has positive refractive power, and has a convex object-side surface S5 and a convex image-side surface S6. The fourth lens element E4 has a negative refractive power, and has a concave object-side surface S7 and a convex image-side surface S8. The fifth lens element E5 has positive refractive power, and has a concave object-side surface S9 and a convex image-side surface S10. The sixth lens element E6 has negative refractive power, and has a concave object-side surface S11 and a concave image-side surface S12. The filter has an object side surface S13 (not shown) and an image side surface S14 (not shown). The light from the object passes through the respective surfaces S1 to S14 in order and is finally imaged on the imaging surface S15 (not shown in the figure).

Table 7 shows a basic parameter table of the optical imaging system of the third embodiment in which the units of the radius of curvature, the thickness/distance, and the focal length are millimeters (mm).

TABLE 7

In this embodiment, the total effective focal length f of the optical imaging system is 4.60mm, the on-axis distance TD from the object side surface of the first lens to the image side surface of the sixth lens is 4.549mm, the half ImgH of the diagonal length of the effective pixel region on the image plane is 3.50mm, and the entrance pupil diameter EPD of the optical imaging system is 2.63mm.

In the third embodiment, both the object-side surface and the image-side surface of any one of the first lens element E1 to the sixth lens element E6 are aspheric. Tables 8-1 to 8-2 show the coefficients A of the high-order terms which can be used for the aspherical mirror surfaces S1 to S12 in the third embodiment ₄ 、A ₆ 、A ₈ 、A ₁₀ 、A ₁₂ 、A ₁₄ 、A ₁₆ 、A ₁₈ 、A ₂₀ 、A ₂₂ 、A ₂₄ 、A ₂₆ 、A ₂₈ And A ₃₀ 。

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

1.1841E-03

7.7915E-03

-3.1097E-02

7.0579E-02

-9.5952E-02

7.9450E-02

-3.9573E-02

S2

-1.1175E-02

1.2469E-03

3.0128E-02

-1.0234E-01

1.8041E-01

-1.8984E-01

1.1809E-01

S3

-7.8330E-02

4.9132E-01

-5.2458E+00

3.8764E+01

-1.9072E+02

6.4907E+02

-1.5682E+03

S4

-4.4570E-03

4.3619E-02

-2.0308E-02

-2.1416E-02

1.4583E-01

-2.7308E-01

2.6265E-01

S5

-8.8575E-02

9.9514E-01

-9.5939E+00

5.7577E+01

-2.3360E+02

6.6601E+02

-1.3659E+03

S6

-2.4492E-02

-5.7964E-02

3.4517E-01

-2.3079E+00

8.9597E+00

-2.1840E+01

3.5381E+01

S7

-9.0326E-03

-3.0132E-02

-7.0155E-01

3.2089E+00

-7.7342E+00

1.2582E+01

-1.4748E+01

S8

4.9556E-02

-1.8255E-01

-1.4846E-02

3.9688E-01

-5.2159E-01

2.8112E-01

2.2353E-02

S9

1.1362E-01

-9.0634E-02

1.1386E-02

-1.7009E-01

5.6728E-01

-8.5955E-01

7.9731E-01

S10

2.6211E-01

-2.4162E-01

3.6909E-01

-5.9370E-01

6.8554E-01

-5.4928E-01

3.0933E-01

S11

2.1774E-02

-6.8637E-02

-1.0565E-01

4.4218E-01

-6.9454E-01

6.6747E-01

-4.3575E-01

S12

-6.9296E-02

-1.5841E-03

5.3953E-02

-7.3573E-02

5.9968E-02

-3.3707E-02

1.3522E-02

TABLE 8-1

TABLE 8-2

The optical imaging systems 310, 320, and 330 in examples 1, 2, and 3 of the third embodiment are different in the structural sizes of the lens barrel and the spacer included therein. Tables 9-1 to 9-2 show some basic parameters of the lens barrels and the spacing elements of the optical imaging systems 310, 320 and 330 of the third embodiment, such as D1s, D1m, D2s, D2m, D3s, D3m, D4s, D4m, D5s, D5m, D0s, EP01, CP1, EP12, EP23, EP34, CP4, EP45, etc., some of the basic parameters shown in tables 9-1 to 9-2 are measured according to the labeling method shown in fig. 1, and the units of the basic parameters shown in tables 9-1 to 9-2 are all millimeters (mm).

Examples/parameters	d1s	d1m	D1m	d2s	d2m	D2m	d3s	d3m	D3m	d4s	d4m	D4m
													3-1	2.325	2.325	5.397	2.388	2.251	5.790	2.947	2.810	5.999	3.805	3.669	6.261
3-2	2.315	2.315	5.397	2.405	2.268	5.790	2.979	2.842	5.999	3.832	3.696	6.261
													3-3	2.331	2.331	5.397	2.373	2.237	5.790	2.932	2.796	5.999	3.754	3.618	6.261

TABLE 9-1

Examples/parameters	d5s	d5m	D5m	d0s	EP01	CP1	EP12	EP23	EP34	CP4	EP45
												3-1	4.535	4.399	6.524	3.862	1.011	0.039	0.711	0.503	0.745	0.039	0.354
3-2	4.553	4.416	6.524	3.862	1.028	0.039	0.704	0.524	0.723	0.039	0.351
												3-3	4.535	4.399	6.524	3.862	1.002	0.039	0.710	0.498	0.739	0.039	0.367

TABLE 9-2

Fig. 13A shows on-axis aberration curves of the optical imaging systems 310, 320, and 330 of the third embodiment, which represent the deviation of the convergent focal points of light rays of different wavelengths after passing through the optical imaging systems 310, 320, and 330. Fig. 13B shows astigmatism curves of the optical imaging systems 310, 320, and 330 of the third embodiment, which represent meridional field curvature and sagittal field curvature corresponding to different image heights. Fig. 13C shows distortion curves of the optical imaging systems 310, 320, and 330 of the third embodiment, which represent distortion magnitude values corresponding to different image heights. As can be seen from fig. 13A to 13C, the optical imaging systems 310, 320, and 330 according to the third embodiment can achieve good imaging quality.

In summary, the conditional expressions of each of the examples in the first to third embodiments satisfy the relationship shown in table 10.

Watch 10

The present application also provides an imaging device whose electron photosensitive element may be a photo-coupled device (CCD) or a complementary metal oxide semiconductor device (CMOS). The imaging device may be a stand-alone imaging device such as a digital camera, or may be an imaging module integrated on a mobile electronic device such as a mobile phone. The imaging device is equipped with the optical imaging system described above.

The foregoing description is only exemplary of the preferred embodiments of the application and is illustrative of the principles of the technology employed. It will be appreciated by those skilled in the art that the scope of the invention herein disclosed is not limited to the particular combination of features described above, but also encompasses other arrangements formed by any combination of features described above or equivalents thereof without departing from the inventive concept. For example, the above features may be replaced with (but not limited to) features having similar functions disclosed in the present application.

Claims (14)

1. An optical imaging system, comprising:

a six-lens group including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in order from an object side to an image side along an optical axis, wherein the second lens and the sixth lens have negative power, and an image side surface of the sixth lens has at least one inflection point;

a plurality of spacing elements, at least including a first spacing element disposed between the first lens and the second lens and abutting against an image side surface of the first lens, and a fifth spacing element disposed between the fifth lens and the sixth lens and abutting against an image side surface of the fifth lens; and

a lens barrel in which the six-piece lens group and the plurality of spacing elements are disposed,

wherein an effective focal length f2 of the second lens, an effective focal length f6 of the sixth lens, an inner diameter d1s of an object side surface of the first spacer element, and an inner diameter d5s of an object side surface of the fifth spacer element satisfy: 1< (f 2 × f 6)/(d 1s × d5 s) <4.

2. The optical imaging system of claim 1, wherein the plurality of spacing elements further comprise:

the second spacing element is arranged between the second lens and the third lens and abuts against the image side surface of the second lens;

the third spacing element is arranged between the third lens and the fourth lens and is abutted against the image side surface of the third lens; and

a fourth spacing element disposed between the fourth lens element and the fifth lens element and abutting against an image side surface of the fourth lens element,

wherein, the total effective focal length f of the optical imaging system, and the inner diameter dis of the object side surface of the spacing element of the lens image side surface, of which the abbe number is less than 50, abutting to the first lens to the sixth lens satisfy: 0.5 sj/dis <2.5, wherein i =2, 3, 4 or 5.

3. The optical imaging system of claim 2, wherein the optical imaging system further satisfies:

2< (Djm + Djm)/EPD <4.5, wherein j =1, 3, 4 or 5,

wherein, when j takes 1, djm represents the inside diameter of the image-side surface of the first spacer element, and Djm represents the outside diameter of the image-side surface of the first spacer element; when j takes 3, djm represents the inside diameter of the image-side surface of the third spacer element, and Djm represents the outside diameter of the image-side surface of the third spacer element; j is 4, djm represents an inner diameter of an image-side surface of the fourth spacer element, and Djm represents an outer diameter of the image-side surface of the fourth spacer element; j is 5, djm represents the inside diameter of the image-side surface of said fifth spacer element, and Djm represents the outside diameter of the image-side surface of said fifth spacer element; EPD is the entrance pupil diameter of the optical imaging system.

4. The optical imaging system according to claim 2, wherein a combined focal length f12 of the first lens and the second lens, a spacing EP01 between an object-side end surface of the lens barrel and the first spacer element along the optical axis, and a maximum thickness CP1 of the first spacer element satisfy: 4 were woven so as to be f12/(EP 01+ CP 1) <7.

5. The optical imaging system of claim 2, wherein the radius of curvature R2 of the image-side surface of the first lens, the radius of curvature R3 of the object-side surface of the second lens, and the inner diameter d1m of the image-side surface of the first spacer element satisfy: 10< (R2 + R3)/d 1m <13.

6. The optical imaging system of claim 2, wherein a combined focal length f23 of the second lens and the third lens, an inner diameter D2m of the image side surface of the second spacer element, and an outer diameter D2m of the image side surface of the second spacer element satisfy: 6< | f23 |/(D2 m + D2 m) <12.

7. The optical imaging system of claim 2, wherein a radius of curvature R6 of an image-side surface of the third lens, a radius of curvature R7 of an object-side surface of the fourth lens, a distance EP12 of the first and second spacing elements along the optical axis, and an inner diameter d3s of the object-side surface of the third spacing element satisfy: 12< (R6 × R7)/(EP 12 × d3 s) <28.

8. The optical imaging system of claim 2, wherein a combined focal length f45 of the fourth lens and the fifth lens, an inner diameter d4s of an object side surface of the fourth spacer element, and an inner diameter d4m of an image side surface of the fourth spacer element satisfy: 0.2 sj & lt f45/(d 4s + d4 m) <3.

9. The optical imaging system of claim 2, wherein a radius of curvature R8 of an image-side surface of the fourth lens, a spacing EP34 of the third and fourth spacing elements along the optical axis, a maximum thickness CP4 of the fourth spacing element, and a spacing EP45 of the fourth and fifth spacing elements along the optical axis satisfy: 1.5< | R8 |/(EP 34+ CP4+ EP 45) <72.

10. The optical imaging system according to claim 2, wherein an on-axis distance TD from an object side surface of the first lens to an image side surface of the sixth lens, an entrance pupil diameter EPD of the optical imaging system, an inner diameter d0s of an object side end surface of the lens barrel, and a spacing EP23 of the second spacer element and the third spacer element along the optical axis satisfy: 4< (TD × EPD)/(d 0s × EP 23) <7.

11. The optical imaging system of claim 2, wherein an effective focal length f3 of the third lens, a center thickness CT3 of the third lens on the optical axis, an inner diameter d2s of an object side surface of the second spacer element, and an inner diameter d3m of an image side surface of the third spacer element satisfy: 0.5< (f 3 × CT 3)/(d 2s × d3 m) <1.5.

12. The optical imaging system of claim 2, wherein the effective focal length f4 of the fourth lens, the effective focal length f5 of the fifth lens, and the inner diameter d5m of the image side surface of the fifth spacer element satisfy: 2< | f4-f5|/d5m <4.

13. The optical imaging system of any of claims 1 to 12, wherein at least three of the first through fourth lenses are meniscus shaped in the paraxial region.

14. The optical imaging system of any of claims 1 to 12, wherein a radius of curvature R1 of the object-side surface of the first lens and a radius of curvature R4 of the image-side surface of the second lens satisfy: r4> R1>0.

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