CN113204097A

CN113204097A - Optical pick-up lens

Info

Publication number: CN113204097A
Application number: CN202110501414.2A
Authority: CN
Inventors: 周进; 张晓彬; 闻人建科; 戴付建; 赵烈烽
Original assignee: Zhejiang Sunny Optics Co Ltd
Current assignee: Zhejiang Sunny Optics Co Ltd
Priority date: 2021-05-08
Filing date: 2021-05-08
Publication date: 2021-08-03
Anticipated expiration: 2041-05-08
Also published as: CN113204097B

Abstract

The invention provides an optical camera lens. The optical camera lens sequentially comprises from an object side to an image side along an optical axis: a first lens; a second lens; a third lens element having a concave object-side surface; a fourth lens; a fifth lens; a sixth lens; the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length f of the optical pick-up lens meet the following requirements: TTL/f < 1.0; the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical image pickup lens satisfy the following conditions: 0.5< (R3+ R4)/f < 1.5; the half of the diagonal length ImgH of the effective pixel area on the imaging surface and the entrance pupil diameter EPD of the optical imaging lens satisfy: 0.5< ImgH/EPD < 1.0. The invention solves the problem of poor imaging quality of the optical camera lens in the prior art.

Description

Optical pick-up lens

Technical Field

The invention relates to the technical field of optical imaging equipment, in particular to an optical camera lens.

Background

The types of optical imaging devices are various, and professional cameras play a smaller role in daily photography at present, and replace the professional cameras with rapidly developed mobile phone photographing functions. On the premise of meeting the traditional communication function, people have higher and higher requirements on the photographing capability of the mobile phone, so that the specifications of the optical camera lens of the mobile phone are continuously improved, and the development of a stable and portable high-quality mobile phone photographing system becomes a necessary trend. At present, products of a plurality of manufacturers develop from single shot to double shot, even three shot, four shot and five shot. The optical camera lens applied to the mobile phone, which is mainstream at present, generally has the characteristics of a large image plane, a wide angle and a long focus, and is matched with a well-modulated algorithm so as to meet the shooting requirements of people using the mobile phone in different scenes. However, many optical cameras have poor shooting capability for distant scenes, so that the shooting effect of distant scenes cannot meet the needs of users.

That is, the optical imaging lens in the related art has a problem of poor imaging quality.

Disclosure of Invention

The invention mainly aims to provide an optical camera lens, which aims to solve the problem of poor imaging quality of the optical camera lens in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided an optical imaging lens comprising, in order from an object side to an image side along an optical axis: a first lens; a second lens; a third lens element having a concave object-side surface; a fourth lens; a fifth lens; a sixth lens; the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length f of the optical pick-up lens meet the following requirements: TTL/f < 1.0; the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical image pickup lens satisfy the following conditions: 0.5< (R3+ R4)/f < 1.5; the half of the diagonal length ImgH of the effective pixel area on the imaging surface and the entrance pupil diameter EPD of the optical imaging lens satisfy: 0.5< ImgH/EPD < 1.0.

Further, the distance SL between the diaphragm and the imaging surface on the axis and the distance TTL between the object side surface of the first lens and the imaging surface on the optical axis satisfy the following condition: 0.5< SL/TTL < 1.5.

Further, an air interval T45 between the fourth lens and the fifth lens on the optical axis and a distance DL between the image side surface of the fourth lens and the imaging surface on the optical axis satisfy: 0.2< T45/DL < 0.7.

Further, an on-axis distance SAG51 between an intersection point of an object-side surface of the fifth lens and the optical axis to an effective radius vertex of the object-side surface of the fifth lens, an on-axis distance SAG52 between an intersection point of an image-side surface of the fifth lens and the optical axis to an effective radius vertex of the image-side surface of the fifth lens, and an on-axis distance SAG62 between an intersection point of an image-side surface of the sixth lens and the optical axis to an effective radius vertex of the image-side surface of the sixth lens satisfy: 0.2< SAG51/(SAG51+ SAG62) < 0.7.

Further, an on-axis distance SAG11 between an intersection point of the object-side surface of the first lens and the optical axis to an effective radius vertex of the object-side surface of the first lens and a maximum effective radius DT11 of the object-side surface of the first lens satisfies: 0.3< SAG11/DT11< 0.8.

Further, the effective focal length f1 of the first lens and the effective focal length f3 of the third lens satisfy: -1.5< f3/f1< -0.5.

Further, the combined focal length f12 of the first lens and the second lens, the effective focal length f5 of the fifth lens, and the effective focal length f6 of the sixth lens satisfy: 0< f12/(| f6| -f5) < 0.5.

Further, the edge thickness ET5 of the fifth lens and the edge thickness ET6 of the sixth lens satisfy: 0< ET6/ET5< 0.7.

Further, the center thickness CT2 of the second lens on the optical axis, the center thickness CT3 of the third lens on the optical axis, the edge thickness ET2 of the second lens, and the edge thickness ET3 of the third lens satisfy: 0.5< (CT2+ CT3)/(ET2+ ET3) < 1.0.

Further, a radius of curvature R9 of the object-side surface of the fifth lens and a radius of curvature R10 of the image-side surface of the fifth lens satisfy: 0< | (R9-R10) |/| (R9+ R10) | < 1.5.

Further, a radius of curvature R7 of the object-side surface of the fourth lens and a radius of curvature R8 of the image-side surface of the fourth lens satisfy: 0.2< R8/(R7+ R8) < 2.0.

Further, the maximum effective radius DT31 of the object-side surface of the third lens, the maximum effective radius DT32 of the image-side surface of the third lens, and the radius of curvature R5 of the object-side surface of the third lens satisfy: -1.0< (DT31+ DT32)/R5< 0.

Further, a center thickness CT1 of the first lens on the optical axis and a curvature radius R1 of an object side surface of the first lens satisfy: 0.3< CT1/R1< 0.8.

Further, a center thickness CT5 of the fifth lens on the optical axis, a center thickness CT6 of the sixth lens on the optical axis, a maximum effective radius DT51 of the object-side surface of the fifth lens, and a maximum effective radius DT61 of the object-side surface of the sixth lens satisfy: 0< (CT5+ CT6)/(DT51+ DT61) < 0.5.

Further, the first lens has positive focal power, and the object side surface of the first lens is a convex surface; the object side surface of the second lens is a convex surface.

Further, the third lens has a negative power; the object side surface of the fourth lens is a convex surface; the fifth lens has a negative power.

According to another aspect of the present invention, there is provided an optical imaging lens comprising, in order from an object side to an image side along an optical axis: a first lens; a second lens; a third lens element having a concave object-side surface; a fourth lens; a fifth lens; a sixth lens; the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length f of the optical pick-up lens meet the following requirements: TTL/f < 1.0; the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical image pickup lens satisfy the following conditions: 0.5< (R3+ R4)/f < 1.5; the distance SL between the diaphragm and the imaging surface on the axis and the distance TTL between the object side surface of the first lens and the imaging surface on the optical axis satisfy the following conditions: 0.5< SL/TTL < 1.5.

Further, a half ImgH of a diagonal length of the effective pixel area on the imaging plane and an entrance pupil diameter EPD of the optical imaging lens satisfy: 0.5< ImgH/EPD < 1.0; an air interval T45 between the fourth lens and the fifth lens on the optical axis and a distance DL between the image side surface of the fourth lens and the imaging surface on the optical axis satisfy: 0.2< T45/DL < 0.7.

By applying the technical scheme of the invention, the optical camera lens sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens from an object side to an image side along an optical axis, and the object side surface of the third lens is a concave surface. The distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length f of the optical pick-up lens meet the following requirements: TTL/f < 1.0; the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical image pickup lens satisfy the following conditions: 0.5< (R3+ R4)/f < 1.5; the half of the diagonal length ImgH of the effective pixel area on the imaging surface and the entrance pupil diameter EPD of the optical imaging lens satisfy: 0.5< ImgH/EPD < 1.0.

The ratio of the distance TTL from the object side surface to the imaging surface on the optical axis and the effective focal length f of the optical camera lens is in a reasonable range, so that the miniaturization of the optical camera lens is guaranteed, a longer focal length can be obtained, and the capability of the optical camera lens for highlighting the main body and the capability of shooting distant scenery are improved. By restraining the relation among the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical pick-up lens within a reasonable range, the contribution of astigmatism and coma aberration of the second lens can be effectively controlled, the imaging quality of the optical pick-up lens is improved, and meanwhile, the shape of the second lens is restrained, and the injection molding and the forming of the second lens are facilitated. The head size of the optical camera lens is restrained favorably by restraining the relation between half of the diagonal length of the effective pixel area on the imaging surface ImgH and the entrance pupil diameter EPD of the optical camera lens within a reasonable range, so that the overall structure distribution of the optical camera lens is more reasonable.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic view showing a configuration of an optical imaging lens according to a first example of the present invention;

fig. 2 to 5 respectively show an on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve of the optical imaging lens in fig. 1;

fig. 6 is a schematic view showing a configuration of an optical imaging lens according to a second example of the present invention;

fig. 7 to 10 show an on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve, respectively, of the optical imaging lens in fig. 6;

fig. 11 is a schematic configuration diagram showing an optical imaging lens according to a third example of the present invention;

fig. 12 to 15 show an on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve, respectively, of the optical imaging lens in fig. 11;

fig. 16 is a schematic view showing a configuration of an optical imaging lens according to example four of the present invention;

fig. 17 to 20 show an on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve, respectively, of the optical imaging lens in fig. 16;

fig. 21 is a schematic view showing a configuration of an optical imaging lens according to example five of the present invention;

fig. 22 to 25 show an on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve, respectively, of the optical imaging lens in fig. 21;

fig. 26 is a schematic view showing a configuration of an optical imaging lens according to example six of the present invention;

fig. 27 to 30 show an on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve, respectively, of the optical imaging lens in fig. 26;

fig. 31 is a schematic view showing a configuration of an optical imaging lens according to a seventh example of the present invention;

fig. 32 to 35 show an on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a chromatic aberration of magnification curve, respectively, of the optical imaging lens in fig. 31.

Wherein the figures include the following reference numerals:

STO, stop; e1, first lens; s1, the object side surface of the first lens; s2, an image side surface of the first lens; e2, second lens; s3, the object side surface of the second lens; s4, an image side surface of the second lens; e3, third lens; s5, the object side surface of the third lens; s6, an image side surface of the third lens; e4, fourth lens; s7, the object side surface of the fourth lens; s8, an image side surface of the fourth lens element; e5, fifth lens; s9, the object side surface of the fifth lens; s10, an image side surface of the fifth lens element; e6, sixth lens; s11, the object-side surface of the sixth lens element; s12, an image side surface of the sixth lens element; e7, optical filters; s13, the object side surface of the optical filter; s14, the image side surface of the optical filter; and S15, imaging surface.

Detailed Description

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 invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

It is noted that, unless otherwise indicated, all 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.

In the present invention, unless specified to the contrary, use of the terms of orientation such as "upper, lower, top, bottom" or the like, generally refer to the orientation as shown in the drawings, or to the component itself in a vertical, perpendicular, or gravitational orientation; likewise, for ease of understanding and description, "inner and outer" refer to the inner and outer relative to the profile of the components themselves, but the above directional words are not intended to limit the invention.

It should be noted that in this specification, the expressions first, second, third, etc. are used only 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 close to the object side becomes the object side surface of the lens, and the surface of each lens close to the image side is called the image side surface of the lens. The determination of the surface shape in the paraxial region can be performed by determining whether or not the surface shape is concave or convex, based on the R value (R denotes the radius of curvature of the paraxial region, and usually denotes the R value in a lens database (lens data) in optical software) in accordance with the determination method of a person ordinarily skilled in the art. For the object side surface, when the R value is positive, the object side surface is judged to be convex, and when the R value is negative, the object side surface is judged to be concave; in the case of the image side surface, the image side surface is determined to be concave when the R value is positive, and is determined to be convex when the R value is negative.

The invention provides an optical camera lens, aiming at solving the problem of poor imaging quality of the optical camera lens in the prior art.

Example one

As shown in fig. 1 to 35, the optical imaging lens includes, in order from an object side to an image side along an optical axis, a first lens element E1, a second lens element E2, a third lens element E3, a fourth lens element E4, a fifth lens element E5, and a sixth lens element E6, and an object side surface S5 of the third lens element is a concave surface. The distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length f of the optical pick-up lens meet the following requirements: TTL/f < 1.0; the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical image pickup lens satisfy the following conditions: 0.5< (R3+ R4)/f < 1.5; the half of the diagonal length ImgH of the effective pixel area on the imaging surface and the entrance pupil diameter EPD of the optical imaging lens satisfy: 0.5< ImgH/EPD < 1.0.

Preferably, 0.8< TTL/f < 1.0.

Preferably, 0.6< (R3+ R4)/f < 1.3.

Preferably 0.6< ImgH/EPD < 0.9.

The ratio of the distance TTL from the object side surface to the imaging surface on the optical axis and the effective focal length f of the optical camera lens is in a reasonable range, so that the miniaturization of the optical camera lens is guaranteed, a longer focal length can be obtained, and the capability of the optical camera lens for highlighting the main body and the capability of shooting distant scenery are improved. By restraining the relation among the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical pick-up lens within a reasonable range, the contribution of astigmatism and coma of the second lens E2 can be effectively controlled, the imaging quality of the optical pick-up lens is favorably improved, and meanwhile, the shape of the second lens E2 is restrained, and the injection molding and the forming of the second lens E2 are favorably realized. The head size of the optical camera lens is restrained favorably by restraining the relation between half of the diagonal length of the effective pixel area on the imaging surface ImgH and the entrance pupil diameter EPD of the optical camera lens within a reasonable range, so that the overall structure distribution of the optical camera lens is more reasonable.

In addition, the optical camera lens has the characteristics of long focus, small visual angle and long focal length, can highlight a shot main body in a smaller picture, makes the picture simpler, blurs the background, and perfectly matches the use requirement of shooting a portrait in daily life for highlighting the main body. Meanwhile, the depth of field is smaller, so that the distant scenery and the nearby scenery can be seen closer, the depth feeling is reduced, and people can not miss the more distant beautiful scenery due to the distance. The distortion is small, and the original outline proportion of the shot scene can be maintained.

In the present embodiment, the on-axis distance SL from the stop to the imaging surface and the distance TTL from the object-side surface of the first lens to the imaging surface on the optical axis satisfy: 0.5< SL/TTL < 1.5. Preferably, 0.7< SL/TTL < 0.9. The ratio of the distance SL from the axis of the diaphragm to the imaging surface to the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis is in a reasonable range, so that the arrangement design of an optical camera lens structure and the improvement of optical performance are facilitated, and meanwhile, the aberration generated by the aperture of the system can be effectively controlled, and the imaging quality of the marginal field of view is improved.

In the present embodiment, an air interval T45 between the fourth lens and the fifth lens on the optical axis and a distance DL between the image side surface of the fourth lens and the imaging surface on the optical axis satisfy: 0.2< T45/DL < 0.7. Preferably, 0.3< T45/DL < 0.5. By controlling the conditional expression within a reasonable range, the distribution of the air intervals of the fourth lens E4, the fifth lens E5 and the sixth lens E6 on the optical axis is more reasonable, which is beneficial to the correction of aberration, avoids overlarge light deflection between the surfaces of the lenses, reduces the processing difficulty of the system, and enhances the working stability of the optical pick-up lens.

In the present embodiment, the on-axis distance SAG51 between the intersection of the object-side surface of the fifth lens and the optical axis to the effective radius vertex of the object-side surface of the fifth lens, the on-axis distance SAG52 between the intersection of the image-side surface of the fifth lens and the optical axis to the effective radius vertex of the image-side surface of the fifth lens, and the on-axis distance SAG62 between the intersection of the image-side surface of the sixth lens and the optical axis to the effective radius vertex of the image-side surface of the sixth lens satisfy: 0.2< SAG51/(SAG51+ SAG62) < 0.7. Preferably, 0.3< SAG51/(SAG51+ SAG62) < 0.6. The focal power of the fifth lens E5 and the sixth lens E6 is reasonably distributed by controlling the rise of the lenses, the residual spherical aberration is balanced to balance the spherical aberration generated by the front four lenses, the spherical aberration of the system is finely adjusted and controlled, and the accurate control of the on-axis field aberration is enhanced. Meanwhile, the processing and molding of the fifth lens E5 and the sixth lens E6 are facilitated.

In the present embodiment, an on-axis distance SAG11 between an intersection point of the object-side surface of the first lens and the optical axis to an effective radius vertex of the object-side surface of the first lens and a maximum effective radius DT11 of the object-side surface of the first lens satisfies: 0.3< SAG11/DT11< 0.8. Preferably, 0.4< SAG11/DT11< 0.6. The rise and the outer diameter proportion of the lens are controlled, the shape of the lens is effectively controlled, injection molding of the first lens E1 is facilitated, processing difficulty is facilitated to be reduced, and system spherical aberration is reduced.

In the present embodiment, the effective focal length f1 of the first lens and the effective focal length f3 of the third lens satisfy: -1.5< f3/f1< -0.5. Preferably-1.3 ≦ f3/f1< -0.7. By controlling the conditional expression in a reasonable range, the size of the optical camera lens can be controlled favorably while the optical camera lens is ensured to have higher aberration correction capability, excessive concentration of focal power in the optical camera lens is avoided, and the aberration can be corrected better by matching with other lenses. In addition, the sensitivity of the first lens E1 and the third lens E3 can be reduced, and the application of the optical imaging lens is more stable.

In the present embodiment, the combined focal length f12 of the first lens and the second lens, the effective focal length f5 of the fifth lens, and the effective focal length f6 of the sixth lens satisfy: 0< f12/(| f6| -f5) < 0.5. Preferably, 0.1< f12/(| f6| -f5) < 0.5. By reasonably constraining the conditional expression, the field curvature contributions of the fifth lens E5 and the sixth lens E6 can be reasonably controlled, so that the system field curvature is balanced in a reasonable state.

In the present embodiment, the edge thickness ET5 of the fifth lens and the edge thickness ET6 of the sixth lens satisfy: 0< ET6/ET5< 0.7. Preferably 0.2< ET6/ET5< 0.6. By controlling the conditional expression within a reasonable range, the space ratio of the fifth lens E5 to the sixth lens E6 can be controlled, which is beneficial to ensuring the assembly process of the lenses and can realize the miniaturization of the optical pick-up lens.

In the present embodiment, the center thickness CT2 of the second lens on the optical axis, the center thickness CT3 of the third lens on the optical axis, the edge thickness ET2 of the second lens, and the edge thickness ET3 of the third lens satisfy: 0.5< (CT2+ CT3)/(ET2+ ET3) < 1.0. Preferably, 0.6< (CT2+ CT3)/(ET2+ ET3) < 0.9. The arrangement is favorable for ensuring that the optical camera lens has better imaging quality and lower sensitivity, and simultaneously, the optical camera lens is easy to perform injection molding processing and has higher yield.

In the present embodiment, a radius of curvature R9 of the object-side surface of the fifth lens and a radius of curvature R10 of the image-side surface of the fifth lens satisfy: 0< | (R9-R10) |/| (R9+ R10) | < 1.5. Preferably, 0.4< | (R9-R10) |/| (R9+ R10) | < 1.1. The arrangement can effectively avoid the situation of image blurring and is beneficial to avoiding ghost images formed by reflection of the fifth lens E5.

In the present embodiment, a radius of curvature R7 of the object-side surface of the fourth lens and a radius of curvature R8 of the image-side surface of the fourth lens satisfy: 0.2< R8/(R7+ R8) < 2.0. Preferably 0.5< R8/(R7+ R8) < 1.7. The arrangement can effectively reduce the sensitivity of the fourth lens E4, is more beneficial to processing and forming, and ensures better imaging quality.

In the present embodiment, the maximum effective radius DT31 of the object-side surface of the third lens, the maximum effective radius DT32 of the image-side surface of the third lens, and the radius of curvature R5 of the object-side surface of the third lens satisfy: -1.0< (DT31+ DT32)/R5< 0. Preferably, -0.9< (DT31+ DT32)/R5< -0.4. The curvature degree of the third lens E3 can be effectively controlled, the sensitivity of the third lens E3 is reduced, the processing difficulty is reduced, the spherical aberration of the optical pick-up lens is reduced, and the imaging quality is improved.

In the present embodiment, the center thickness CT1 of the first lens on the optical axis and the radius of curvature R1 of the object side surface of the first lens satisfy: 0.3< CT1/R1< 0.8. Preferably 0.4< CT1/R1< 0.7. The bending degree of the first lens E1 can be effectively restrained in a reasonable range by limiting the conditional expression, the sensitivity is favorably reduced, the processing and the forming are more favorably realized, and the yield is favorably improved.

In the present embodiment, the center thickness CT5 of the fifth lens on the optical axis, the center thickness CT6 of the sixth lens on the optical axis, the maximum effective radius DT51 of the object-side surface of the fifth lens, and the maximum effective radius DT61 of the object-side surface of the sixth lens satisfy: 0< (CT5+ CT6)/(DT51+ DT61) < 0.5. Preferably, 0.2< (CT5+ CT6)/(DT51+ DT61) < 0.5. The lens with the large caliber is favorably formed and assembled, and the conditions of welding marks and reflection ghost images are avoided.

In the present embodiment, the first lens E1 has positive optical power, and the object-side surface S1 of the first lens is convex; the object side S3 of the second lens is convex. By reasonably distributing the focal power of the first lens E1, the distribution of the focal power of the whole optical camera lens is facilitated, the excessive concentration of the focal power is avoided, and simultaneously, the balance between vertical axis chromatic aberration and transverse chromatic aberration is facilitated, so that higher imaging quality is obtained.

In the present embodiment, the third lens E3 has negative power; the object side surface S7 of the fourth lens is convex; the fifth lens E5 has a negative power. The arrangement can effectively reduce the aberration of the peripheral field of view while increasing the light transmission quantity, is favorable for reasonable distribution of focal power of the whole optical camera lens, and is favorable for improving the imaging quality.

Example two

The optical imaging lens includes, in order from an object side to an image side along an optical axis, a first lens element E1, a second lens element E2, a third lens element E3, a fourth lens element E4, a fifth lens element E5, and a sixth lens element E6, and an object side surface S5 of the third lens element is a concave surface. The distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length f of the optical pick-up lens meet the following requirements: TTL/f < 1.0; the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical image pickup lens satisfy the following conditions: 0.5< (R3+ R4)/f < 1.5; the distance SL between the diaphragm and the imaging surface on the axis and the distance TTL between the object side surface of the first lens and the imaging surface on the optical axis satisfy the following conditions: 0.5< SL/TTL < 1.5.

Preferably, 0.8< TTL/f < 1.0.

Preferably, 0.6< (R3+ R4)/f < 1.3.

Preferably, 0.7< SL/TTL < 0.9.

The ratio of the distance TTL from the object side surface to the imaging surface on the optical axis and the effective focal length f of the optical camera lens is in a reasonable range, so that the miniaturization of the optical camera lens is guaranteed, a longer focal length can be obtained, and the capability of the optical camera lens for highlighting the main body and the capability of shooting distant scenery are improved. By restraining the relation among the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical pick-up lens within a reasonable range, the contribution of astigmatism and coma of the second lens E2 can be effectively controlled, the imaging quality of the optical pick-up lens is favorably improved, and meanwhile, the shape of the second lens E2 is restrained, and the injection molding and the forming of the second lens E2 are favorably realized. The ratio of the distance SL from the axis of the diaphragm to the imaging surface to the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis is in a reasonable range, so that the arrangement design of an optical camera lens structure and the improvement of optical performance are facilitated, and meanwhile, the aberration generated by the aperture of the system can be effectively controlled, and the imaging quality of the marginal field of view is improved.

In the present embodiment, a relationship between half of the diagonal length ImgH of the effective pixel area on the imaging plane and the entrance pupil diameter EPD of the optical imaging lens satisfies: 0.5< ImgH/EPD < 1.0. Preferably 0.6< ImgH/EPD < 0.9. The head size of the optical camera lens is restrained favorably by restraining the relation between half of the diagonal length of the effective pixel area on the imaging surface ImgH and the entrance pupil diameter EPD of the optical camera lens within a reasonable range, so that the overall structure distribution of the optical camera lens is more reasonable.

In the embodiment, the first lens has positive focal power, and the object side surface of the first lens is a convex surface; the object side surface of the second lens is a convex surface. The first lens E1 has positive focal power, and the object side surface S1 of the first lens is a convex surface; the object side S3 of the second lens is convex. By reasonably distributing the focal power of the first lens E1, the distribution of the focal power of the whole optical camera lens is facilitated, the excessive concentration of the focal power is avoided, and simultaneously, the balance between vertical axis chromatic aberration and transverse chromatic aberration is facilitated, so that higher imaging quality is obtained.

The optical pick-up lens may further include at least one stop STO to improve the imaging quality of the optical pick-up lens. Alternatively, the stop STO may be disposed between the first lens E1 and the second lens E2. Alternatively, the above-described optical imaging lens may further include a filter E7 for correcting color deviation and/or a protective glass for protecting a photosensitive element located on the image plane.

The optical imaging lens in the present application may employ a plurality of lenses, for example, the above-described six lenses. By reasonably distributing the focal power, the surface shape, the central thickness of each lens, the axial distance between each lens and the like, the aperture of the optical camera lens can be effectively increased, the sensitivity of the optical camera lens can be reduced, and the machinability of the optical camera lens can be improved, so that the optical camera lens is more beneficial to production and processing and can be suitable for portable electronic equipment such as smart phones. The optical imaging lens also has a large aperture. The advantages of ultra-thin and good imaging quality can meet the miniaturization requirement of intelligent electronic products.

In the present application, at least one of the mirror surfaces of each lens 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 during imaging can be eliminated as much as possible, thereby improving the imaging quality.

However, it will be appreciated by those skilled in the art that the number of lenses constituting an optical imaging lens may be varied without departing from the technical solutions claimed in the present application to obtain the respective results and advantages described in the present specification. For example, although six lenses are exemplified in the embodiment, the optical imaging lens is not limited to six lenses. The optical camera lens may also include other numbers of lenses, if desired.

Specific surface types and parameters of the optical imaging lens applicable to the above embodiments are further described below with reference to the drawings.

It should be noted that any one of the following examples one to seven is applicable to all embodiments of the present application.

Example one

As shown in fig. 1 to 5, an optical imaging lens of the first example of the present application is described. Fig. 1 shows a schematic configuration diagram of an optical imaging lens of example one.

As shown in fig. 1, the optical imaging lens includes, in order from an object side to an image side: a first lens E1, a stop STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a filter E7, and an image forming surface S15.

The first lens element E1 has positive refractive power, and the object-side surface S1 of the first lens element is convex, and the image-side surface S2 of the first lens element is concave. The second lens element E2 has positive refractive power, and the object-side surface S3 of the second lens element is convex, and the image-side surface S4 of the second lens element is concave. The third lens E3 has negative power, and the object-side surface S5 of the third lens is concave, and the image-side surface S6 of the third lens is concave. The fourth lens element E4 has positive refractive power, and the object-side surface S7 of the fourth lens element is convex and the image-side surface S8 of the fourth lens element is concave. The fifth lens element E5 has negative power, and the object-side surface S9 of the fifth lens element is convex and the image-side surface S10 of the fifth lens element is concave. The sixth lens element E6 has positive refractive power, and has a convex object-side surface S11 and a convex image-side surface S12. The light from the object sequentially passes through the respective surfaces S1 to S14 and is finally imaged on the imaging surface S15.

In this example, the total effective focal length f of the optical imaging lens is 8.10mm, the on-axis distance TTL from the object-side surface S1 of the first lens to the imaging surface S15 is 7.20mm, and the half of the maximum field angle Semi-FOV of the optical imaging lens is 19.8 °.

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

TABLE 1

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

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/R (i.e., paraxial curvature c is the inverse of 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 below gives the high-order coefficient coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, and A26 that can be used for each of the aspherical mirrors S1-S12 in example one.

TABLE 2

Fig. 2 shows an axial chromatic aberration curve of the optical imaging lens of the first example, which shows the deviation of the convergence focus of light rays of different wavelengths after passing through the optical imaging lens. Fig. 3 shows astigmatism curves of the optical imaging lens of the first example, which represent meridional field curvature and sagittal field curvature. Fig. 4 shows distortion curves of the optical imaging lens of the first example, which show values of distortion magnitudes corresponding to different angles of view. Fig. 5 shows a chromatic aberration of magnification curve of the optical imaging lens of the first example, which shows a deviation of different image heights on the image forming surface after the light passes through the optical imaging lens.

As can be seen from fig. 2 to 5, the optical imaging lens according to the first example can achieve good imaging quality.

Example two

As shown in fig. 6 to 10, an optical imaging lens of example two of the present application is described. In this example and the following examples, descriptions of parts similar to example one will be omitted for the sake of brevity. Fig. 6 shows a schematic configuration diagram of an optical imaging lens of example two.

As shown in fig. 6, the optical imaging lens includes, in order from an object side to an image side: a first lens E1, a stop STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a filter E7, and an image forming surface S15.

The first lens element E1 has positive refractive power, and the object-side surface S1 of the first lens element is convex, and the image-side surface S2 of the first lens element is concave. The second lens element E2 has positive refractive power, and the object-side surface S3 of the second lens element is convex, and the image-side surface S4 of the second lens element is concave. The third lens E3 has negative power, and the object-side surface S5 of the third lens is concave, and the image-side surface S6 of the third lens is concave. The fourth lens element E4 has positive refractive power, and the object-side surface S7 of the fourth lens element is convex and the image-side surface S8 of the fourth lens element is concave. The fifth lens element E5 has negative power, and the object-side surface S9 of the fifth lens element is convex and the image-side surface S10 of the fifth lens element is concave. The sixth lens element E6 has positive refractive power, and the object-side surface S11 of the sixth lens element is convex and the image-side surface S12 of the sixth lens element is concave. The light from the object sequentially passes through the respective surfaces S1 to S14 and is finally imaged on the imaging surface S15.

In this example, the total effective focal length f of the optical imaging lens is 8.10mm, the on-axis distance TTL from the object-side surface S1 of the first lens to the imaging surface S15 is 7.18mm, and the half of the maximum field angle Semi-FOV of the optical imaging lens is 19.7 °.

Table 3 shows a basic structural parameter table of the optical imaging lens of example two, in which the units of the radius of curvature, the thickness/distance, and the focal length are all millimeters (mm).

TABLE 3

Table 4 shows the high-order term coefficients that can be used for each aspherical mirror surface in example two, wherein each aspherical mirror surface type can be defined by formula (1) given in example one above.

TABLE 4

Fig. 7 shows an axial chromatic aberration curve of the optical imaging lens of example two, which shows the deviation of the convergence focus of light rays of different wavelengths after passing through the optical imaging lens. Fig. 8 shows astigmatism curves of the optical imaging lens of example two, which represent meridional field curvature and sagittal field curvature. Fig. 9 shows distortion curves of the optical imaging lens of example two, which show values of distortion magnitudes corresponding to different angles of view. Fig. 10 shows a chromatic aberration of magnification curve of the optical imaging lens of the second example, which shows a deviation of different image heights on the image forming surface after the light passes through the optical imaging lens.

As can be seen from fig. 7 to 10, the optical imaging lens according to example two can achieve good imaging quality.

Example III

As shown in fig. 11 to 15, an optical imaging lens of example three of the present application is described. In this example and the following examples, descriptions of parts similar to example one will be omitted for the sake of brevity. Fig. 11 shows a schematic configuration diagram of an optical imaging lens of example three.

As shown in fig. 11, the optical imaging lens includes, in order from an object side to an image side: a first lens E1, a stop STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a filter E7, and an image forming surface S15.

The first lens element E1 has positive refractive power, and the object-side surface S1 and the image-side surface S2 of the first lens element are convex. The second lens element E2 has positive refractive power, and the object-side surface S3 of the second lens element is convex, and the image-side surface S4 of the second lens element is concave. The third lens E3 has negative power, and the object-side surface S5 of the third lens is concave, and the image-side surface S6 of the third lens is concave. The fourth lens element E4 has positive refractive power, and the object-side surface S7 of the fourth lens element is convex and the image-side surface S8 of the fourth lens element is concave. The fifth lens element E5 has negative power, and the object-side surface S9 of the fifth lens element is convex and the image-side surface S10 of the fifth lens element is concave. The sixth lens element E6 has positive refractive power, and has a convex object-side surface S11 and a convex image-side surface S12. The light from the object sequentially passes through the respective surfaces S1 to S14 and is finally imaged on the imaging surface S15.

In this example, the total effective focal length f of the optical imaging lens is 8.09mm, the on-axis distance TTL from the object-side surface S1 of the first lens to the imaging surface S15 is 7.98mm, and the half of the maximum field angle Semi-FOV of the optical imaging lens is 19.1 °.

Table 5 shows a basic structural parameter table of the optical imaging lens of example three, in which the units of the radius of curvature, the thickness/distance, and the focal length are all millimeters (mm).

TABLE 5

Table 6 shows the high-order term coefficients that can be used for each aspherical mirror surface in example three, wherein each aspherical mirror surface type can be defined by formula (1) given in example one above.

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

-4.0367E-04

-1.1035E-03

1.8591E-03

-2.2257E-03

1.8350E-03

-1.1833E-03

6.3017E-04

S2

-1.7277E-02

1.4792E-02

-5.8264E-03

1.2775E-03

-9.1908E-06

-1.0933E-04

4.0741E-05

S3

-3.8051E-02

-8.1753E-03

2.5474E-02

-3.4876E-02

3.6161E-02

-2.5452E-02

1.1673E-02

S4

-8.0469E-03

-3.7738E-02

4.3013E-02

-4.3842E-02

3.4945E-02

-9.5449E-03

-8.0348E-03

S5

5.3301E-02

-1.2951E-02

8.4531E-03

-3.1909E-02

5.5059E-02

-4.5940E-02

1.9263E-02

S6

3.0280E-03

4.0466E-02

-1.2771E-01

3.7741E-01

-8.1895E-01

1.2205E+00

-1.2276E+00

S7

-5.3891E-02

1.6367E-02

4.0877E-02

-1.4853E-01

2.8467E-01

-3.3971E-01

2.6018E-01

S8

-1.0096E-02

9.8389E-03

2.6090E-02

-6.6685E-02

9.8801E-02

-8.3944E-02

3.1681E-02

S9

-1.0177E-01

6.7703E-02

-7.3204E-02

1.0502E-01

-1.2290E-01

9.8221E-02

-5.2849E-02

S10

-1.1643E-01

3.7994E-02

2.8313E-03

-1.1268E-02

6.0437E-03

-1.4935E-03

5.4570E-05

S11

-8.6993E-03

-3.6053E-02

4.1558E-02

-2.8100E-02

1.3910E-02

-5.2007E-03

1.4302E-03

S12

3.2981E-03

-1.9440E-02

1.7209E-02

-1.1008E-02

5.0542E-03

-1.5895E-03

3.3088E-04

Flour mark

A18

A20

A22

A24

A26

A28

A30

S1

-2.7294E-04

9.1290E-05

-2.2429E-05

3.8685E-06

-4.4210E-07

3.0108E-08

-9.2937E-10

S2

-7.5491E-06

7.3901E-07

-3.0973E-08

0.0000E+00

S3

-3.4523E-03

6.3845E-04

-6.7384E-05

3.1024E-06

0.0000E+00

S4

7.8366E-03

-2.7291E-03

4.2833E-04

-2.2537E-05

-5.0920E-07

0.0000E+00

S5

-2.0812E-03

-1.8274E-03

9.7068E-04

-2.0468E-04

1.6860E-05

0.0000E+00

S6

8.2293E-01

-3.5394E-01

8.8032E-02

-8.4454E-03

-9.8735E-04

2.2513E-04

0.0000E+00

S7

-1.2388E-01

3.2380E-02

-2.4254E-03

-7.7745E-04

1.4568E-04

0.0000E+00

S8

1.0316E-02

-1.8583E-02

9.4675E-03

-2.2976E-03

2.2441E-04

0.0000E+00

S9

1.9139E-02

-4.5722E-03

6.7803E-04

-5.2778E-05

8.6753E-07

9.7524E-08

0.0000E+00

S10

7.4692E-05

-2.2806E-05

3.1768E-06

-2.2247E-07

6.0225E-09

2.9202E-11

0.0000E+00

S11

-2.7888E-04

3.7100E-05

-3.1878E-06

1.5925E-07

-3.5140E-09

0.0000E+00

S12

-4.3300E-05

3.1653E-06

-7.5014E-08

-5.7080E-09

4.9711E-10

-1.9389E-11

5.2684E-13

TABLE 6

Fig. 12 shows an on-axis chromatic aberration curve of the optical imaging lens of example three, which shows the deviation of the convergence focus of light rays of different wavelengths after passing through the optical imaging lens. Fig. 13 shows astigmatism curves representing meridional field curvature and sagittal field curvature of the optical imaging lens of example three. Fig. 14 shows distortion curves of the optical imaging lens of example three, which show values of distortion magnitudes corresponding to different angles of view. Fig. 15 shows a chromatic aberration of magnification curve of the optical imaging lens of example three, which shows the deviation of different image heights on the image forming surface after the light rays pass through the optical imaging lens.

As can be seen from fig. 12 to 15, the optical imaging lens according to the third example can achieve good imaging quality.

Example four

As shown in fig. 16 to 20, an optical imaging lens of the present example four is described. In this example and the following examples, descriptions of parts similar to example one will be omitted for the sake of brevity. Fig. 16 shows a schematic configuration diagram of an optical imaging lens of example four.

As shown in fig. 16, the optical imaging lens includes, in order from an object side to an image side: a first lens E1, a stop STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a filter E7, and an image forming surface S15.

The first lens element E1 has positive refractive power, and the object-side surface S1 and the image-side surface S2 of the first lens element are convex. The second lens element E2 has positive refractive power, and the object-side surface S3 of the second lens element is convex, and the image-side surface S4 of the second lens element is concave. The third lens E3 has negative power, and the object-side surface S5 of the third lens is concave, and the image-side surface S6 of the third lens is concave. The fourth lens element E4 has positive refractive power, and the object-side surface S7 of the fourth lens element is convex and the image-side surface S8 of the fourth lens element is concave. The fifth lens element E5 has negative power, and the object-side surface S9 of the fifth lens element is concave, and the image-side surface S10 of the fifth lens element is convex. 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 light from the object sequentially passes through the respective surfaces S1 to S14 and is finally imaged on the imaging surface S15.

In this example, the total effective focal length f of the optical imaging lens is 8.10mm, the on-axis distance TTL from the object-side surface S1 of the first lens to the imaging surface S15 is 6.70mm, and the half of the maximum field angle Semi-FOV of the optical imaging lens is 20.3 °.

Table 7 shows a basic structural parameter table of the optical imaging lens of example four, in which the units of the radius of curvature, the thickness/distance, and the focal length are all millimeters (mm).

TABLE 7

Table 8 shows the high-order term coefficients that can be used for each aspherical mirror surface in example four, wherein each aspherical mirror surface type can be defined by formula (1) given in example one above.

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

-2.1710E-03

5.8178E-04

-3.0296E-03

4.6887E-03

-4.5805E-03

2.7953E-03

-1.0979E-03

S2

-5.7436E-03

-4.4596E-03

3.8889E-02

-7.8980E-02

8.9184E-02

-6.2146E-02

2.7327E-02

S3

-3.1384E-02

-5.1441E-02

1.9525E-01

-4.1344E-01

4.5874E-01

-2.1752E-01

-5.4038E-02

S4

-8.5086E-03

-1.2760E-01

5.8491E-01

-1.6695E+00

2.8439E+00

-3.0385E+00

2.0825E+00

S5

5.9886E-02

-6.0067E-02

5.9964E-01

-2.5083E+00

6.2966E+00

-1.0577E+01

1.2376E+01

S6

1.8566E-03

-9.8794E-02

1.8281E+00

-1.0980E+01

4.0953E+01

-1.0160E+02

1.7159E+02

S7

-1.0815E-01

1.4596E-02

-1.7825E-01

1.7668E+00

-7.2155E+00

1.7537E+01

-2.7396E+01

S8

-5.9592E-02

2.7945E-01

-2.2489E+00

1.0817E+01

-3.2872E+01

6.6780E+01

-9.2386E+01

S9

-1.7223E-01

8.8292E-01

-2.0045E+00

2.7127E+00

-2.6887E+00

2.0808E+00

-1.2219E+00

S10

-3.1847E-01

1.3006E+00

-2.3267E+00

2.4705E+00

-1.7619E+00

8.8839E-01

-3.2343E-01

S11

-3.1331E-01

6.3923E-01

-7.1406E-01

5.2099E-01

-2.6778E-01

9.9207E-02

-2.6424E-02

S12

-3.0446E-01

3.7563E-01

-3.5383E-01

2.4943E-01

-1.3098E-01

5.0261E-02

-1.3858E-02

Flour mark

A18

A20

A22

A24

A26

A28

A30

S1

2.6998E-04

-3.7853E-05

2.2564E-06

0.0000E+00

S2

-7.4011E-03

1.1286E-03

-7.4177E-05

0.0000E+00

S3

1.2703E-01

-6.8811E-02

1.7194E-02

-1.7041E-03

0.0000E+00

S4

-9.0390E-01

2.3453E-01

-3.1539E-02

1.4651E-03

0.0000E+00

S5

-1.0153E+01

5.7322E+00

-2.1203E+00

4.6211E-01

-4.4926E-02

0.0000E+00

S6

-1.9747E+02

1.5171E+02

-7.3753E+01

1.9973E+01

-1.9604E+00

-1.4017E-01

0.0000E+00

S7

2.8199E+01

-1.8960E+01

7.9342E+00

-1.8152E+00

1.4112E-01

1.1355E-02

0.0000E+00

S8

8.6864E+01

-5.4080E+01

2.0824E+01

-4.1242E+00

1.2587E-01

6.2126E-02

0.0000E+00

S9

5.0011E-01

-1.2369E-01

1.1045E-02

2.8715E-03

-1.0797E-03

1.6311E-04

-1.2243E-05

S10

8.4985E-02

-1.5710E-02

1.9146E-03

-1.3216E-04

2.9554E-06

1.0518E-07

0.0000E+00

S11

4.9818E-03

-6.4534E-04

5.4285E-05

-2.6294E-06

5.1349E-08

3.3016E-10

0.0000E+00

S12

2.6971E-03

-3.6147E-04

3.2276E-05

-1.8846E-06

8.0877E-08

-3.5112E-09

1.1084E-10

TABLE 8

Fig. 17 shows an on-axis chromatic aberration curve of the optical imaging lens of example four, which shows the deviation of the convergence focus of light rays of different wavelengths after passing through the optical imaging lens. Fig. 18 shows astigmatism curves of the optical imaging lens of example four, which represent meridional field curvature and sagittal field curvature. Fig. 19 shows distortion curves of the optical imaging lens of example four, which show values of distortion magnitudes corresponding to different angles of view. Fig. 20 shows a chromatic aberration of magnification curve of the optical imaging lens of example four, which shows a deviation of different image heights on the image formation plane after the light ray passes through the optical imaging lens.

As can be seen from fig. 17 to 20, the optical imaging lens according to example four can achieve good image quality.

Example five

As shown in fig. 21 to 25, an optical imaging lens of example five of the present application is described. In this example and the following examples, descriptions of parts similar to example one will be omitted for the sake of brevity. Fig. 21 shows a schematic configuration diagram of an optical imaging lens of example five.

As shown in fig. 21, the optical imaging lens includes, in order from an object side to an image side: a first lens E1, a stop STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a filter E7, and an image forming surface S15.

The first lens element E1 has positive refractive power, and the object-side surface S1 and the image-side surface S2 of the first lens element are convex. The second lens element E2 has negative power, and the object-side surface S3 of the second lens element is convex, and the image-side surface S4 of the second lens element is concave. The third lens E3 has negative power, and the object-side surface S5 of the third lens is concave, and the image-side surface S6 of the third lens is concave. The fourth lens element E4 has positive refractive power, and the object-side surface S7 and the image-side surface S8 of the fourth lens element are convex. The fifth lens element E5 has negative power, and the object-side surface S9 of the fifth lens element is convex and the image-side surface S10 of the fifth lens element is concave. The sixth lens element E6 has positive refractive power, and the object-side surface S11 of the sixth lens element is convex and the image-side surface S12 of the sixth lens element is concave. The light from the object sequentially passes through the respective surfaces S1 to S14 and is finally imaged on the imaging surface S15.

In this example, the total effective focal length f of the optical imaging lens is 8.21mm, the on-axis distance TTL from the object-side surface S1 of the first lens to the imaging surface S15 is 8.00mm, and the half of the maximum field angle Semi-FOV of the optical imaging lens is 19.6 °.

Table 9 shows a basic structural parameter table of the optical imaging lens of example five, in which the units of the radius of curvature, the thickness/distance, and the focal length are all millimeters (mm).

TABLE 9

Table 10 shows the high-order term coefficients that can be used for each aspherical mirror surface in example five, wherein each aspherical mirror surface type can be defined by formula (1) given in example one above.

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

-7.4847E-04

-6.9191E-04

1.4487E-03

-2.6638E-03

2.9124E-03

-2.0127E-03

8.8018E-04

S2

-1.2535E-02

1.1481E-02

-1.1830E-03

-4.4646E-03

4.3311E-03

-2.2350E-03

7.3881E-04

S3

-4.5629E-02

-1.9083E-02

5.1325E-02

-8.6023E-02

1.2141E-01

-1.2930E-01

9.4912E-02

S4

-2.1831E-02

-6.4588E-02

1.4365E-01

-3.4259E-01

6.5225E-01

-8.5595E-01

7.6318E-01

S5

8.6409E-02

-1.8655E-02

-2.3778E-03

1.9215E-02

-7.8783E-02

2.5072E-01

-4.5097E-01

S6

1.4661E-02

6.9349E-02

-1.8023E-01

6.0407E-01

-1.7392E+00

3.6921E+00

-5.4692E+00

S7

-1.2080E-01

8.1973E-02

-7.1108E-02

1.2690E-01

-2.8096E-01

6.1178E-01

-1.0327E+00

S8

-5.5513E-02

5.1182E-02

-6.6456E-02

1.9728E-01

-4.3322E-01

6.6572E-01

-7.0378E-01

S9

-4.8208E-02

1.1381E-02

-8.9956E-04

-9.6318E-03

1.6085E-02

-1.5238E-02

9.4882E-03

S10

-8.6093E-02

3.8236E-02

-2.0232E-02

8.6918E-03

-2.9179E-03

7.4381E-04

-1.5208E-04

S11

-4.3312E-02

1.5480E-02

-2.6955E-03

-1.1225E-03

1.2322E-03

-5.7167E-04

1.6494E-04

S12

-2.4607E-02

4.7360E-03

-3.7518E-04

3.0648E-04

-4.5211E-04

2.9411E-04

-1.0857E-04

Flour mark

A18

A20

A22

A24

A26

A28

A30

S1

-2.3695E-04

3.5845E-05

-2.3463E-06

0.0000E+00

S2

-1.6143E-04

2.2138E-05

-1.4910E-06

0.0000E+00

S3

-4.6021E-02

1.4089E-02

-2.4666E-03

1.8776E-04

0.0000E+00

S4

-4.5894E-01

1.7837E-01

-4.0227E-02

3.9667E-03

0.0000E+00

S5

4.8733E-01

-3.2921E-01

1.3679E-01

-3.2000E-02

3.2211E-03

0.0000E+00

S6

5.5323E+00

-3.7018E+00

1.5289E+00

-3.2333E-01

9.4974E-03

5.9121E-03

0.0000E+00

S7

1.2255E+00

-9.7530E-01

4.9454E-01

-1.4438E-01

1.8468E-02

0.0000E+00

S8

5.0149E-01

-2.3134E-01

6.3572E-02

-8.6466E-03

3.1777E-04

0.0000E+00

S9

-3.9608E-03

1.0875E-03

-1.8628E-04

1.7748E-05

-6.9803E-07

0.0000E+00

S10

2.8233E-05

-4.9009E-06

6.7072E-07

-5.8376E-08

2.5616E-09

-3.3053E-11

0.0000E+00

S11

-3.1352E-05

3.9228E-06

-3.1125E-07

1.4225E-08

-2.8621E-10

0.0000E+00

S12

2.4976E-05

-3.6606E-06

3.3454E-07

-1.7806E-08

4.8558E-10

-7.1291E-12

1.7876E-13

Watch 10

Fig. 22 shows an on-axis chromatic aberration curve of the optical imaging lens of example five, which shows the deviation of the convergence focus of light rays of different wavelengths after passing through the optical imaging lens. Fig. 23 shows astigmatism curves of the optical imaging lens of example five, which represent meridional field curvature and sagittal field curvature. Fig. 24 shows distortion curves of the optical imaging lens of example five, which show values of distortion magnitudes corresponding to different angles of view. Fig. 25 shows a chromatic aberration of magnification curve of the optical imaging lens of example five, which shows a deviation of different image heights on the image formation plane after light passes through the optical imaging lens.

As can be seen from fig. 22 to 25, the optical imaging lens according to example five can achieve good imaging quality.

Example six

As shown in fig. 26 to 30, an optical imaging lens of example six of the present application is described. In this example and the following examples, descriptions of parts similar to example one will be omitted for the sake of brevity. Fig. 26 shows a schematic configuration diagram of an optical imaging lens of example six.

As shown in fig. 26, the optical imaging lens, in order from an object side to an image side, comprises: a first lens E1, a stop STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a filter E7, and an image forming surface S15.

The first lens element E1 has positive refractive power, and the object-side surface S1 of the first lens element is convex, and the image-side surface S2 of the first lens element is concave. The second lens element E2 has positive refractive power, and the object-side surface S3 and the image-side surface S4 of the second lens element are convex. The third lens E3 has negative power, and the object-side surface S5 of the third lens is concave, and the image-side surface S6 of the third lens is concave. The fourth lens element E4 has positive refractive power, and the object-side surface S7 of the fourth lens element is convex and the image-side surface S8 of the fourth lens element is concave. The fifth lens E5 has negative power, and the object-side surface S9 of the fifth lens is concave, and the image-side surface S10 of the fifth lens is concave. The sixth lens element E6 has positive refractive power, and the object-side surface S11 of the sixth lens element is convex and the image-side surface S12 of the sixth lens element is concave. The light from the object sequentially passes through the respective surfaces S1 to S14 and is finally imaged on the imaging surface S15.

In this example, the total effective focal length f of the optical imaging lens is 8.10mm, the on-axis distance TTL from the object-side surface S1 of the first lens to the imaging surface S15 is 7.25mm, and the half of the maximum field angle Semi-FOV of the optical imaging lens is 19.7 °.

Table 11 shows a basic structural parameter table of the optical imaging lens of example six, in which the units of the radius of curvature, thickness/distance, and focal length are all millimeters (mm).

TABLE 11

Table 12 shows the high-order term coefficients that can be used for each of the aspherical mirror surfaces in example six, wherein each aspherical mirror surface type can be defined by formula (1) given in example one above.

Flour mark

A4

A6

A8

A10

A12

A14

S1

-3.9126E-03

5.5560E-03

-8.1789E-03

6.2685E-03

-2.4102E-03

9.6645E-05

S2

-4.0789E-03

3.7028E-03

-2.0496E-03

7.2312E-04

-1.5739E-04

2.0402E-05

S3

-3.9986E-02

3.2906E-02

-2.2402E-02

-2.3487E-02

5.3489E-02

-4.2997E-02

S4

-2.5621E-02

2.9181E-02

-1.6452E-02

-6.8345E-02

1.3156E-01

-1.0901E-01

S5

5.8788E-02

3.6621E-03

1.6625E-01

-6.9800E-01

1.3124E+00

-1.4824E+00

S6

-8.6818E-02

3.5958E-01

-1.3778E+00

4.8121E+00

-1.1813E+01

1.9628E+01

S7

-1.2334E-01

-1.0738E-01

9.8826E-01

-3.2957E+00

6.9144E+00

-9.8675E+00

S8

-2.0449E-02

4.6180E-02

-4.1083E-01

1.7621E+00

-4.2575E+00

6.4843E+00

S9

-8.0389E-02

2.4025E-02

3.5168E-02

-1.2039E-01

1.4693E-01

-1.0092E-01

S10

-1.9319E-01

2.3157E-01

-2.0472E-01

1.2175E-01

-5.1093E-02

1.5530E-02

S11

-1.6497E-01

1.8075E-01

-1.1334E-01

4.2437E-02

-1.0264E-02

1.6998E-03

S12

-1.3553E-01

1.0562E-01

-6.9069E-02

3.4964E-02

-1.3143E-02

3.5014E-03

Flour mark

A16

A18

A20

A22

A24

A26

S1

2.9478E-04

-1.1840E-04

1.9365E-05

-1.2001E-06

0.0000E+00

S2

-1.4355E-06

3.6856E-08

1.1399E-09

-6.4474E-11

0.0000E+00

S3

1.9150E-02

-5.1057E-03

8.0573E-04

-6.8753E-05

2.4019E-06

0.0000E+00

S4

5.1203E-02

-1.4445E-02

2.4069E-03

-2.1590E-04

7.8839E-06

0.0000E+00

S5

1.1051E+00

-5.6054E-01

1.9206E-01

-4.2541E-02

5.4905E-03

-3.1301E-04

S6

-2.2220E+01

1.7187E+01

-8.9433E+00

2.9925E+00

-5.8105E-01

4.9703E-02

S7

9.7821E+00

-6.7000E+00

3.0954E+00

-9.1799E-01

1.5751E-01

-1.1876E-02

S8

-6.5246E+00

4.4191E+00

-2.0008E+00

5.8200E-01

-9.8511E-02

7.3816E-03

S9

4.3605E-02

-1.2331E-02

2.2871E-03

-2.6856E-04

1.8126E-05

-5.3573E-07

S10

-3.4451E-03

5.5304E-04

-6.2526E-05

4.7108E-06

-2.1156E-07

4.2684E-09

S11

-2.0079E-04

1.7444E-05

-1.1308E-06

5.3209E-08

-1.6231E-09

2.3603E-11

S12

-6.4335E-04

8.0388E-05

-6.6947E-06

3.5546E-07

-1.0885E-08

1.4630E-10

TABLE 12

Fig. 27 shows an on-axis chromatic aberration curve of the optical imaging lens of example six, which shows the deviation of the convergent focus of light rays of different wavelengths after passing through the optical imaging lens. Fig. 28 shows astigmatism curves representing meridional field curvature and sagittal field curvature of the optical imaging lens of example six. Fig. 29 shows distortion curves of the optical imaging lens of example six, which indicate values of distortion magnitudes corresponding to different angles of view. Fig. 30 shows a chromatic aberration of magnification curve of the optical imaging lens of example six, which shows the deviation of different image heights on the image forming surface after the light rays pass through the optical imaging lens.

As can be seen from fig. 27 to 30, the optical imaging lens according to example six can achieve good image quality.

Example seven

As shown in fig. 31 to 35, an optical imaging lens of example seven of the present application is described. In this example and the following examples, descriptions of parts similar to example one will be omitted for the sake of brevity. Fig. 31 shows a schematic configuration diagram of an optical imaging lens of example seven.

As shown in fig. 31, the optical imaging lens includes, in order from an object side to an image side: a first lens E1, a stop STO, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a filter E7, and an image forming surface S15.

The first lens element E1 has positive refractive power, and the object-side surface S1 of the first lens element is convex, and the image-side surface S2 of the first lens element is concave. The second lens element E2 has positive refractive power, and the object-side surface S3 of the second lens element is convex, and the image-side surface S4 of the second lens element is concave. The third lens element E3 has negative power, and the object-side surface S5 of the third lens element is concave, and the image-side surface S6 of the third lens element is convex. The fourth lens element E4 has positive refractive power, and the object-side surface S7 of the fourth lens element is convex and the image-side surface S8 of the fourth lens element is concave. The fifth lens element E5 has negative power, and the object-side surface S9 of the fifth lens element is convex and the image-side surface S10 of the fifth lens element is concave. The sixth lens element E6 has positive refractive power, and the object-side surface S11 of the sixth lens element is convex and the image-side surface S12 of the sixth lens element is concave. The light from the object sequentially passes through the respective surfaces S1 to S14 and is finally imaged on the imaging surface S15.

In this example, the total effective focal length f of the optical imaging lens is 8.09mm, the on-axis distance TTL from the object-side surface S1 of the first lens to the imaging surface S15 is 7.35mm, and the half of the maximum field angle Semi-FOV of the optical imaging lens is 19.5 °.

Table 13 shows a basic structural parameter table of the optical imaging lens of example seven, in which the units of the radius of curvature, the thickness/distance, and the focal length are all millimeters (mm).

Watch 13

Table 14 shows the high-order term coefficients that can be used for each of the aspherical mirror surfaces in example seven, wherein each of the aspherical mirror surface types can be defined by formula (1) given in example one above.

Flour mark

A4

A6

A8

A10

A12

A14

S1

-1.7051E-03

1.6024E-03

-1.5611E-03

7.9179E-04

-2.0148E-04

5.3465E-06

S2

-9.5340E-03

1.3265E-02

-1.1254E-02

6.0854E-03

-2.0300E-03

4.0332E-04

S3

-2.7386E-02

1.8885E-02

-1.0774E-02

-9.4647E-03

1.8062E-02

-1.2166E-02

S4

-2.4591E-02

2.7782E-02

-1.5538E-02

-6.4027E-02

1.2226E-01

-1.0048E-01

S5

5.9436E-02

3.7321E-03

1.7078E-01

-7.2278E-01

1.3698E+00

-1.5597E+00

S6

-8.4565E-02

3.4654E-01

-1.3138E+00

4.5398E+00

-1.1027E+01

1.8127E+01

S7

-1.3732E-01

-1.2645E-01

1.2311E+00

-4.3426E+00

9.6372E+00

-1.4548E+01

S8

-2.3450E-02

5.6853E-02

-5.4298E-01

2.5003E+00

-6.4852E+00

1.0604E+01

S9

-9.2460E-02

2.9709E-02

4.6755E-02

-1.7208E-01

2.2579E-01

-1.6675E-01

S10

-2.3463E-01

3.1071E-01

-3.0347E-01

1.9939E-01

-9.2443E-02

3.1044E-02

S11

-1.8973E-01

2.2350E-01

-1.5068E-01

6.0652E-02

-1.5772E-02

2.8081E-03

S12

-1.5251E-01

1.2640E-01

-8.7899E-02

4.7320E-02

-1.8917E-02

5.3592E-03

Flour mark

A16

A18

A20

A22

A24

A26

S1

1.0792E-05

-2.8688E-06

3.1052E-07

-1.2736E-08

0.0000E+00

S2

-4.3494E-05

1.7115E-06

8.1129E-08

-7.0332E-09

0.0000E+00

S3

4.5406E-03

-1.0144E-03

1.3414E-04

-9.5918E-06

2.8079E-07

0.0000E+00

S4

4.6820E-02

-1.3103E-02

2.1657E-03

-1.9270E-04

6.9801E-06

0.0000E+00

S5

1.1720E+00

-5.9926E-01

2.0697E-01

-4.6210E-02

6.0119E-03

-3.4547E-04

S6

-2.0303E+01

1.5538E+01

-7.9996E+00

2.6483E+00

-5.0878E-01

4.3060E-02

S7

1.5255E+01

-1.1052E+01

5.4012E+00

-1.6944E+00

3.0752E-01

-2.4527E-02

S8

-1.1454E+01

8.3285E+00

-4.0481E+00

1.2642E+00

-2.2971E-01

1.8479E-02

S9

7.7459E-02

-2.3551E-02

4.6961E-03

-5.9288E-04

4.3020E-05

-1.3671E-06

S10

-7.6081E-03

1.3493E-03

-1.6854E-04

1.4028E-05

-6.9604E-07

1.5514E-08

S11

-3.5661E-04

3.3308E-05

-2.3214E-06

1.1744E-07

-3.8514E-09

6.0214E-11

S12

-1.0472E-03

1.3915E-04

-1.2324E-05

6.9585E-07

-2.2660E-08

3.2389E-10

TABLE 14

Fig. 32 shows an on-axis chromatic aberration curve of the optical imaging lens of example seven, which indicates that light rays of different wavelengths are out of focus after passing through the optical imaging lens. Fig. 33 shows astigmatism curves representing meridional field curvature and sagittal field curvature of the optical imaging lens of example seven. Fig. 34 shows distortion curves of the optical imaging lens of example seven, which indicate values of distortion magnitudes corresponding to different angles of view. Fig. 35 shows a chromatic aberration of magnification curve of the optical imaging lens of example seven, which shows a deviation of different image heights on the image formation plane after light passes through the optical imaging lens.

As can be seen from fig. 32 to 35, the optical imaging lens according to example seven can achieve good image quality.

To sum up, examples one to seven respectively satisfy the relationships shown in table 15.

Conditional formula/example	1	2	3	4	5	6	7
								TTL/f	0.89	0.89	0.99	0.83	0.97	0.90	0.91
(R3+R4)/f	0.99	1.09	1.00	1.17	0.77	0.62	1.24
								ImgH/EPD	0.83	0.82	0.65	0.83	0.83	0.83	0.82
SL/TTL	0.80	0.80	0.78	0.79	0.83	0.83	0.76
								T45/DL	0.42	0.40	0.37	0.37	0.33	0.44	0.41
SAG51/(SAG51+SAG62)	0.40	0.36	0.42	0.42	0.58	0.47	0.43
								SAG11/DT11	0.48	0.51	0.56	0.56	0.45	0.48	0.53
f3/f1	-0.76	-1.06	-1.01	-1.11	-1.28	-0.77	-0.85
								f12/(\|f6\|-f5)	0.29	0.29	0.41	0.17	0.30	0.28	0.32
ET6/ET5	0.52	0.36	0.30	0.58	0.23	0.35	0.42
								(CT2+CT3)/(ET2+ET3)	0.78	0.77	0.67	0.75	0.78	0.72	0.84
\|(R9-R10)\|/\|(R9+R10)\|	0.92	0.49	0.76	0.77	0.78	1.01	0.91
								R8/(R7+R8)	0.60	0.54	0.92	0.51	1.63	0.67	0.61
(DT31+DT32)/R5	-0.48	-0.56	-0.57	-0.44	-0.51	-0.68	-0.85
								CT1/R1	0.55	0.54	0.65	0.60	0.51	0.48	0.69
(CT5+CT6)/(DT51+DT61)	0.33	0.34	0.34	0.29	0.42	0.31	0.31

Watch 15

Table 16 gives effective focal lengths f of the optical imaging lenses of examples one to seven, effective focal lengths f1 to f6 of the respective lenses, Semi-FOV of the maximum angle of view, and the like.

Basic data/examples	1	2	3	4	5	6	7
								f1(mm)	4.21	4.01	4.37	3.85	4.13	4.37	4.76
f2(mm)	31.93	50.01	134.43	27.89	-80.43	26.15	31.36
								f3(mm)	-3.20	-4.25	-4.41	-4.29	-5.28	-3.34	-4.03
f4(mm)	8.15	24.37	17.94	55.63	36.04	7.57	10.53
								f5(mm)	-4.42	-4.30	-4.61	-10.39	-5.77	-4.16	-4.29
f6(mm)	8.46	8.44	5.53	-10.14	7.96	9.92	8.91
								f(mm)	8.10	8.10	8.09	8.10	8.21	8.10	8.09
TTL(mm)	7.20	7.18	7.98	6.70	8.00	7.25	7.35
								ImgH(mm)	2.91	2.91	2.91	2.91	2.91	2.91	2.91
f/EPD	2.32	2.28	1.80	2.30	2.35	2.31	2.29
								Semi-FOV(°)	19.8	19.7	19.1	20.3	19.6	19.7	19.5

TABLE 16

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 lens described above.

It is to be understood that the above-described embodiments are only a few, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular is intended to include the plural unless the context clearly dictates otherwise, and it should be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of features, steps, operations, devices, components, and/or combinations thereof.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are capable of operation in sequences other than those illustrated or described herein.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

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

a first lens;

a second lens;

a third lens element having a concave object-side surface;

a fourth lens;

a fifth lens;

a sixth lens;

the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis and the effective focal length f of the optical pick-up lens meet the following requirements: TTL/f < 1.0;

the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens and the effective focal length f of the optical image pickup lens satisfy that: 0.5< (R3+ R4)/f < 1.5;

half ImgH of the diagonal length of the effective pixel area on the imaging surface and the entrance pupil diameter EPD of the optical imaging lens satisfy: 0.5< ImgH/EPD < 1.0.

2. An optical imaging lens according to claim 1, wherein an on-axis distance SL from a stop to the imaging surface and a distance TTL from an object side surface of the first lens to the imaging surface on the optical axis satisfy: 0.5< SL/TTL < 1.5.

3. An optical imaging lens according to claim 1, wherein an air interval T45 between the fourth lens and the fifth lens on the optical axis and a distance DL between an image side surface of the fourth lens and the imaging surface on the optical axis satisfy: 0.2< T45/DL < 0.7.

4. The optical imaging lens of claim 1, wherein an on-axis distance SAG51 between an intersection point of an object-side surface of the fifth lens and the optical axis to an effective radius vertex of the object-side surface of the fifth lens, an on-axis distance SAG52 between an intersection point of an image-side surface of the fifth lens and the optical axis to an effective radius vertex of an image-side surface of the fifth lens, and an on-axis distance SAG62 between an intersection point of an image-side surface of the sixth lens and the optical axis to an effective radius vertex of an image-side surface of the sixth lens satisfy: 0.2< SAG51/(SAG51+ SAG62) < 0.7.

5. The optical imaging lens according to claim 1, wherein an on-axis distance SAG11 between an intersection point of the object-side surface of the first lens and the optical axis and an effective radius vertex of the object-side surface of the first lens and a maximum effective radius DT11 of the object-side surface of the first lens satisfies: 0.3< SAG11/DT11< 0.8.

6. The optical imaging lens according to claim 1, wherein an effective focal length f1 of the first lens and an effective focal length f3 of the third lens satisfy: -1.5< f3/f1< -0.5.

7. The optical imaging lens according to claim 1, wherein a combined focal length f12 of the first lens and the second lens, an effective focal length f5 of the fifth lens, and an effective focal length f6 of the sixth lens satisfy: 0< f12/(| f6| -f5) < 0.5.

8. An optical imaging lens according to claim 1, wherein an edge thickness ET5 of the fifth lens and an edge thickness ET6 of the sixth lens satisfy: 0< ET6/ET5< 0.7.

9. The optical imaging lens according to claim 1, wherein a center thickness CT2 of the second lens on the optical axis, a center thickness CT3 of the third lens on the optical axis, an edge thickness ET2 of the second lens, and an edge thickness ET3 of the third lens satisfy: 0.5< (CT2+ CT3)/(ET2+ ET3) < 1.0.

10. An optical imaging lens, comprising, in order from an object side to an image side along an optical axis:

a first lens;

a second lens;

a third lens element having a concave object-side surface;

a fourth lens;

a fifth lens;

a sixth lens;

the distance SL from the diaphragm to the imaging surface on the axis and the distance TTL from the object side surface of the first lens to the imaging surface on the optical axis satisfy the following conditions: 0.5< SL/TTL < 1.5.