阅读说明：本技术 光学镜头及成像设备 (Optical lens and imaging apparatus ) 是由 章彬炜 熊儒韬 曾昊杰 于 2021-11-09 设计创作，主要内容包括：本发明公开了一种光学镜头及成像设备,该光学镜头沿光轴从物侧到成像面依次包括：具有正光焦度的第一透镜,其物侧面为凸面、像侧面为凹面；具有负光焦度的第二透镜,其物侧面为凸面、像侧面为凹面；具有正光焦度的第三透镜,其物侧面为凸面、像侧面为凸面；具有正光焦度的第四透镜,其物侧面为凹面、像侧面为凸面；具有正光焦度的第五透镜,其物侧面为凹面、像侧面为凸面；具有负光焦度的第六透镜,其物侧面在近光轴处为凹面、像侧面在近光轴处为凹面,且第六透镜的物侧面和像侧面都至少有一个反曲点。本发明通过将各透镜的面型、光焦度及放置位置合理搭配,使其结构紧凑,实现大光圈、镜头小型化和高像素均衡。(The invention discloses an optical lens and imaging equipment, the optical lens includes from the object side to the imaging surface along the optical axis in turn: the first lens with positive focal power, its object side is a convex surface, the image side is a concave surface; a second lens with negative focal power, wherein the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; a third lens with positive focal power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; a fourth lens with positive focal power, wherein the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; a fifth lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a sixth lens element having a negative optical power, an object-side surface being concave at a paraxial region and an image-side surface being concave at a paraxial region, the sixth lens element having at least one inflection point on both the object-side surface and the image-side surface. The invention reasonably matches the surface type, focal power and placement position of each lens, so that the structure is compact, and the miniaturization and high pixel balance of the large aperture and the lens are realized.)

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

the lens comprises a first lens with positive focal power, a second lens and a third lens, wherein the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface;

the second lens is provided with negative focal power, and the object side surface of the second lens is a convex surface and the image side surface of the second lens is a concave surface;

the third lens is provided with positive focal power, and the object side surface and the image side surface of the third lens are convex surfaces;

the fourth lens is provided with positive focal power, and the object side surface of the fourth lens is a concave surface while the image side surface is a convex surface;

the fifth lens is provided with positive focal power, the object side surface of the fifth lens is a concave surface, and the image side surface of the fifth lens is a convex surface;

a sixth lens element having a negative optical power, an object-side surface of the sixth lens element being concave at a paraxial region and an image-side surface of the sixth lens element being concave at a paraxial region, and at least one inflection point on both the object-side surface and the image-side surface of the sixth lens element;

wherein, the optical lens satisfies the conditional expression:

0.1<TC1/TTL<0.2；

wherein TC1 denotes a center thickness of the first lens, and TTL denotes an optical total length of the optical lens.

2. An optical lens according to claim 1, characterized in that the optical lens satisfies the following conditional expression:

1.1<TTL/f<1.2；

wherein, TTL represents the optical total length of the optical lens, and f represents the effective focal length of the optical lens.

3. An optical lens according to claim 1, characterized in that the optical lens satisfies the following conditional expression:

2.8<D/TC1<4.2；

where D denotes an entrance pupil diameter of the optical lens, and TC1 denotes a center thickness of the first lens.

4. An optical lens according to claim 1, characterized in that the optical lens satisfies the following conditional expression:

0.2<(1/f1-1/f3)/(1/f)<1.2；

wherein f1 denotes an effective focal length of the first lens, f3 denotes an effective focal length of the third lens, and f denotes an effective focal length of the optical lens.

5. An optical lens according to claim 1, characterized in that the optical lens satisfies the following conditional expression:

4.2< DM62/DM31<4.7；

wherein DM62 represents an effective half aperture of an image-side surface of the sixth lens, and DM31 represents an effective half aperture of an object-side surface of the third lens.

6. An optical lens according to claim 1, characterized in that the optical lens satisfies the following conditional expression:

0.7<f1/f<1.2；

where f denotes an effective focal length of the optical lens, and f1 denotes an effective focal length of the first lens.

7. An optical lens according to claim 1, characterized in that the optical lens satisfies the following conditional expression:

0.18 mm^-2<(1/R11-1/R32)/ DT<0.22 mm^-2；

wherein R32 denotes a radius of curvature of an image-side surface of the third lens, R11 denotes a radius of curvature of an object-side surface of the first lens, and DT denotes a stop aperture of the optical lens.

8. An optical lens according to claim 1, characterized in that the optical lens satisfies the following conditional expression:

0<Φ3/Φ1<1；

where Φ 1 represents the power of the first lens, and Φ 3 represents the power of the third lens.

9. An optical lens according to claim 1, characterized in that the optical lens satisfies the following conditional expression:

-110<R32/R11<20；

wherein R11 denotes a radius of curvature of an object side surface of the first lens, and R32 denotes a radius of curvature of an image side surface of the third lens.

10. An imaging apparatus comprising the optical lens according to any one of claims 1 to 9 and an imaging element for converting an optical image formed by the optical lens into an electric signal.

Technical Field

The present invention relates to the field of imaging lens technology, and in particular, to an optical lens and an imaging device.

Background

At present, with the rapid development of portable electronic products, people's daily life is greatly facilitated, and the effect of watching the images in close proximity can be achieved even if the images are separated by thousands of miles, at present, teleconferencing, live webcast, security monitoring, video phones, vehicle-mounted images and the like capture images through optical lenses and convert the images into electric signals through equipment to complete transmission.

However, with the continuous updating and development of mobile information technology, electronic devices such as smart phones are developing in the directions of being light, thin, high-definition, full-screen, and the like, which constitutes an increasing requirement for the imaging quality of optical lenses. At present, most manufacturers in the market have great limitation on improving the optical performance in order to pursue the overall small size of the lens, so that the performance of the lens is relatively greatly influenced while the original miniaturization of the lens volume is ensured, and the compatibility between high-definition pixels of the lens and the miniaturization of the lens cannot be well achieved.

Disclosure of Invention

Therefore, an object of the present invention is to provide an optical lens and an imaging apparatus to solve the above problems.

The embodiment of the invention implements the above object by the following technical scheme.

In a first aspect, the present invention provides an optical lens, comprising, in order from an object side to an image plane along an optical axis: the lens comprises a diaphragm, a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens. The first lens has positive focal power, the object side surface is a convex surface, and the image side surface is a concave surface; the second lens has negative focal power, the object side surface is a convex surface, and the image side surface is a concave surface; the third lens has positive focal power, the object side surface is a convex surface, and the image side surface is a convex surface; the fourth lens has positive focal power, the object side surface is a concave surface, and the image side surface is a convex surface; the fifth lens has positive focal power, the object side surface is a concave surface, and the image side surface is a convex surface; the sixth lens element has a negative optical power, and the object side surface is concave at the paraxial region and the image side surface is concave at the paraxial region; the object side surfaces and the image side surfaces of the six lenses are provided with at least one inflection point; the optical lens satisfies the conditional expression: 0.1< TC1/TTL < 0.2; wherein TC1 denotes a center thickness of the first lens, and TTL denotes an optical total length of the optical lens.

In a second aspect, the present invention provides an imaging apparatus, comprising an imaging element and the optical lens provided in the first aspect, wherein the imaging element is configured to convert an optical image formed by the optical lens into an electrical signal.

Compared with the prior art, the optical lens and the imaging equipment provided by the invention have the advantages that the lens shapes and focal powers among six lenses with specific focal powers are reasonably matched, so that the structure among the lenses is more compact while high pixels are met, the imaging quality is improved while the miniaturization of the lens is well realized, and the shooting experience of a user can be effectively improved.

Drawings

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

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

FIG. 2 is a field curvature graph of an optical lens according to a first embodiment of the present invention;

FIG. 3 is a distortion curve diagram of an optical lens according to a first embodiment of the present invention;

FIG. 4 is a graph of axial spherical aberration of an optical lens according to a first embodiment of the present invention;

FIG. 5 is a lateral chromatic aberration diagram of an optical lens according to a first embodiment of the present invention;

FIG. 6 is a schematic structural diagram of an optical lens system according to a second embodiment of the present invention;

FIG. 7 is a field curvature graph of an optical lens according to a second embodiment of the present invention;

FIG. 8 is a distortion curve diagram of an optical lens according to a second embodiment of the present invention;

FIG. 9 is a graph of on-axis spherical aberration of an optical lens according to a second embodiment of the present invention;

FIG. 10 is a lateral chromatic aberration diagram of an optical lens according to a second embodiment of the present invention;

FIG. 11 is a schematic structural diagram of an optical lens assembly according to a third embodiment of the present invention;

FIG. 12 is a field curvature graph of an optical lens according to a third embodiment of the present invention;

fig. 13 is a distortion graph of an optical lens according to a third embodiment of the present invention;

FIG. 14 is a graph of on-axis spherical aberration of an optical lens according to a third embodiment of the present invention;

FIG. 15 is a lateral chromatic aberration diagram of an optical lens according to a third embodiment of the present invention;

FIG. 16 is a schematic structural diagram of an optical lens assembly according to a fourth embodiment of the present invention;

FIG. 17 is a field curvature graph of an optical lens according to a fourth embodiment of the present invention;

fig. 18 is a distortion graph of an optical lens according to a fourth embodiment of the present invention;

FIG. 19 is a graph of on-axis spherical aberration of an optical lens according to a fourth embodiment of the present invention;

FIG. 20 is a lateral chromatic aberration diagram of an optical lens according to a fourth embodiment of the present invention;

FIG. 21 is a graph of ghost image energy before improvement in P1 according to the present invention;

FIG. 22 is a schematic diagram of the ghost image before P1 improvement according to the present invention;

FIG. 23 is a graph of the ghost image energy after P1 improvement according to the present invention;

fig. 24 is a schematic configuration diagram of an image forming apparatus according to a fifth embodiment of the present invention.

Detailed Description

In order to make the objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. Several embodiments of the invention are presented in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, 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 invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Like reference numerals refer to like elements throughout the specification.

The present invention provides an optical lens, sequentially including, from an object side to an image plane along an optical axis: the stop, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the filter are located on the object side opposite to the image plane.

The first lens has positive focal power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface;

the second lens has negative focal power, and the object side surface and the image side surface of the second lens are convex and concave;

the third lens has positive focal power, and both the object side surface and the image side surface of the third lens are convex surfaces;

the fourth lens has positive focal power, the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface;

the fifth lens has positive focal power, the object side surface of the fifth lens is a concave surface, and the image side surface of the fifth lens is a convex surface;

the sixth lens has negative focal power, and the object side surface paraxial axis and the image side surface paraxial axis of the sixth lens are both concave.

As an embodiment, the optical lens satisfies the following conditional expression:

0.1<TC1/TTL<0.2；（1）

where TC1 denotes a center thickness of the first lens, and TTL denotes an optical total length of the optical lens.

When the conditional expression (1) is satisfied, the volume of the lens can be reasonably controlled so as to meet the current development trend of the lens. Specifically, when the light source is out of the range of 0.1< TC1/TTL <0.2, an internal reflection ghost image of the first lens is generated after the included angle between the light source and the optical axis of the lens is greater than 55 ° (as shown in fig. 21), and the energy is relatively high, which seriously affects the quality of an imaged picture (as shown in fig. 22); when the requirement that 0.1< TC1/TTL <0.2 is met, the energy of the P1 internal reflection ghost image is effectively improved (as shown in figure 23), and the imaging quality is improved, so that the imaging quality is greatly improved while the lens meets the development trend of size miniaturization, and the compatibility requirement of a client on high-definition pixel imaging and lens miniaturization is favorably met.

As an embodiment, the optical lens may further satisfy the following conditional expression:

1.1<TTL/f<1.2；（2）

wherein, TTL represents the optical total length of the optical lens, and f represents the effective focal length of the optical lens.

When the conditional expression (2) is satisfied, the optical lens can be reasonably controlled to meet the miniaturization requirement. Specifically, when the TTL/f is 1.1, the lens can be ensured to be in a required shooting range; when TTL/f is less than 1.2, the optical total length of the optical lens can be minimized.

As an embodiment, the optical lens may further satisfy the following conditional expression:

2.8<D/TC1<4.2；(3)

where D denotes an entrance pupil diameter of the optical lens, and TC1 denotes a center thickness of the first lens.

When the conditional expression (3) is satisfied, the characteristic that the lens has high-definition pixels can be ensured. Specifically, when the ratio of D/TC1 is 2.8< D/TC1, the luminous flux can be effectively increased, more light rays can be ensured to enter the optical system, and the illumination intensity is increased; when the D/TC1 is less than 4.2, the risk of generating ghost images is effectively reduced and the imaging quality is improved while more light rays are ensured to enter the optical system.

As an embodiment, the optical lens may further satisfy the following conditional expression:

0.2<(1/f1-1/f3)/(1/f)<1.2；（4）

where f1 denotes an effective focal length of the first lens, f3 denotes an effective focal length of the third lens, and f denotes an effective focal length of the optical lens.

When the conditional expression (4) is satisfied, the eccentric sensitivity of the first lens can be shared on the third lens, the aperture of the third lens is relatively small, the eccentric sensitivity cannot be large, the difficulty of production and processing can be greatly reduced by balancing the eccentric sensitivities of the first lens and the third lens, and the production yield of the lens can be effectively improved while the high imaging quality is ensured.

As an embodiment, the optical lens may further satisfy the following conditional expression:

4.2< DM62/DM31<4.7；（5）

where DM62 denotes the effective half aperture of the image-side surface of the sixth lens, and DM31 denotes the effective half aperture of the object-side surface of the third lens.

When the conditional expression (5) is satisfied, when 4.2< DM62/DM31, the third lens can correct the aberration of the second lens and transmit the light to the fourth lens at a proper angle, which is helpful for aberration compensation and increases the area of the imaging surface, but if the ratio of DM62/DM31 is too large, the lens size is also large, which does not meet the miniaturization trend; when DM32/DM31 is less than 4.7, the aperture of the optical lens can be reasonably controlled, so that the size of the head of the lens is smaller, the miniaturization characteristic of the size of the lens is ensured, and the full-screen high-definition pixel imaging and the miniaturization compatibility of the lens are favorably realized.

As an embodiment, the optical lens may further satisfy the following conditional expression:

0.7<f1/f<1.2；（6）

where f denotes an effective focal length of the optical lens, and f1 denotes an effective focal length of the first lens.

With conditional expression (6), when the value of f1/f exceeds the lower limit, high-order aberrations are generated for off-axis light, resulting in a decrease in imaging performance; when the value of f1/f exceeds the upper limit, correction of aberration and curvature of field is difficult, and eccentricity sensitivity is increased.

As an embodiment, the optical lens may further satisfy the following conditional expression:

0.18 mm^-2<(1/R11-1/R32)/ DT<0.22 mm^-2；（7）

where R32 denotes a radius of curvature of an image-side surface of the third lens, R11 denotes a radius of curvature of an object-side surface of the first lens, and DT denotes a stop aperture of the optical lens.

For the conditional expression (7), when the aberration of the lens head is 0.18< (1/R11-1/R32)/DT, the aberration of the lens head can be well modified, and the high-definition pixel characteristic is met; when (1/R11-1/R32)/DT is less than 0.22, the light can be ensured to transmit through the lens smoothly, the risk of generating ghost images is reduced, and the miniaturization characteristic of the lens is met.

As an embodiment, the optical lens may further satisfy the following conditional expression:

0<Φ3/Φ1<1；（8）

where Φ 1 denotes the power of the first lens, and Φ 3 denotes the power of the third lens.

When the ratio of 0 to phi 3/phi 1 is less than 0, the length of the lens group can be well controlled, and the structural design is facilitated; when phi 3/phi 1 is less than 1, the defocusing curve dispersion of each field of view can be well controlled, and the imaging quality of the telephoto lens is modified.

As an embodiment, the optical lens may further satisfy the following conditional expression:

-110<R32/R11<20；（9）

where R11 denotes a radius of curvature of the object-side surface of the first lens, and R32 denotes a radius of curvature of the image-side surface of the third lens.

When the conditional expression (9) is satisfied, the effective aperture of the lens at the head of the lens can be well controlled, the resolving power of the edge of the lens is effectively improved, and the edge aberration is effectively reduced.

In one embodiment, the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element and the sixth lens element are plastic aspheric lens elements. The aspheric lens can effectively reduce the number of the lenses, correct aberration and provide better optical performance.

The invention is further illustrated below in the following examples. In various embodiments, the thickness, the curvature radius, and the material selection of each lens in the optical lens are different, and the specific differences can be referred to in the parameter tables of the various embodiments. The following examples are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited only by the following examples, and any other changes, substitutions, combinations or simplifications which do not depart from the innovative points of the present invention should be construed as being equivalent substitutions and shall be included within the scope of the present invention.

In the embodiments of the present invention, when the lenses in the optical lens are aspheric lenses, the aspheric surface types of the lenses all satisfy the following equation:

；

wherein z is the distance rise from the aspheric surface vertex when the aspheric surface is at the position with the height h along the optical axis direction, c is the paraxial curvature of the surface, k is the quadric coefficient, A_2iIs the aspheric surface type coefficient of 2i order.

First embodiment

Referring to fig. 1, a schematic structural diagram of an optical lens 100 according to a first embodiment of the present invention is shown, where the optical lens 100 sequentially includes, from an object side to an image plane along an optical axis: the lens system includes a stop ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter G1.

The first lens element L1 is a plastic aspheric lens with positive refractive power, 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 L2 is a plastic aspheric lens with negative refractive power, 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 L3 is a plastic aspheric lens with positive refractive power, the object-side surface S5 of the third lens element is convex, and the image-side surface S6 of the third lens element is convex;

the fourth lens element L4 is a plastic aspheric lens with positive refractive power, the object-side surface S7 of the fourth lens element is concave, and the image-side surface S8 of the fourth lens element is convex;

the fifth lens element L5 is a plastic aspheric lens with positive refractive power, 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 L6 is a plastic aspheric lens with negative power, the sixth lens element having an object-side surface S11 that is concave at the paraxial region and has a inflection point, and the sixth lens element having an image-side surface S12 that is concave at the paraxial region and has an inflection point.

Specifically, the present embodiment provides an optical deviceThe design parameters of the lens 100 are shown in Table 1, where R represents the radius of curvature (mm), d represents the optical surface separation (mm), and n represents_dRepresents the refractive index, V, of the material at the dominant wavelength (555 nm)_dRepresents the abbe number of the material.

TABLE 1

The surface shape coefficients of the aspherical surfaces of the optical lens 100 in the present embodiment are shown in table 2.

TABLE 2

In the present embodiment, graphs of curvature of field, distortion, on-axis spherical aberration and lateral chromatic aberration of the optical lens 100 are shown in fig. 2, 3, 4 and 5, respectively.

The curves in fig. 2 show field curvatures at different image heights at the image plane in the meridional direction and the sagittal direction. The abscissa represents the offset and the ordinate represents the field angle, and it can be seen from the figure that the field curvature offset of the image plane in the meridional direction and the astigmatism direction is controlled within ± 0.1mm, which indicates that the field curvature correction of the optical lens is good.

The curves in fig. 3 represent F-tan θ distortions corresponding to different image heights on the image plane. The abscissa represents the magnitude of distortion and the ordinate represents the field angle, and it can be seen from the figure that the distortion is controlled within ± 2.5% in the imaging field required by the lens, indicating that the distortion is well corrected.

The curve of FIG. 4 shows the on-axis point spherical aberration, the abscissa shows the offset, and the ordinate shows the normalized radius of the pupil, and it can be seen from the graph that the axial chromatic aberration of the shortest wavelength and the maximum wavelength are controlled within + -0.05 mm, which shows that the on-axis point spherical aberration is well corrected.

Fig. 5 is a graph showing chromatic aberration of each wavelength at different image heights on the image plane with respect to the main wavelength, in which the abscissa shows the chromatic aberration value and the ordinate shows the normalized angle of view. As can be seen from the figure, the chromatic aberration of each wavelength relative to the central wavelength is controlled within +/-1.5 microns in different fields of view, and the transverse chromatic aberration of the optical lens is well corrected.

Second embodiment

Referring to fig. 6, a schematic structural diagram of an optical lens 200 according to a second embodiment of the present invention is shown, where the structural changes of the optical lens 200 in the present embodiment and the optical lens 100 in the first embodiment are not large, and the largest change is the central thickness of the fourth lens element.

The present embodiment provides the relevant parameters of each lens in the optical lens 200 as shown in table 3.

TABLE 3

The surface shape coefficients of the aspherical surfaces of the optical lens 200 in the present embodiment are shown in table 4.

TABLE 4

In the present embodiment, graphs of curvature of field, distortion, chromatic aberration of point on axis, and lateral chromatic aberration of the optical lens 200 are shown in fig. 7, 8, 9, and 10, respectively.

Fig. 7 shows the field curvature of different image heights at the image plane in the tangential direction and the sagittal direction, and it can be seen from the figure that the field curvature in both the tangential direction and the sagittal direction is controlled within ± 0.2mm, which indicates that the lens field curvature correction is good.

Fig. 8 shows F-tan θ distortion of different image heights on the image plane, and it can be seen that the distortion of different image heights on the image plane is controlled within ± 2.5%, which indicates that the lens distortion correction is good.

FIG. 9 shows the on-axis spherical aberration, and it can be seen that the chromatic aberration at all wavelengths is controlled within. + -. 0.02mm, indicating that the on-axis spherical aberration of the lens is also well corrected.

FIG. 10 shows chromatic aberration of each wavelength with respect to the main wavelength for different fields, and it can be seen from the graph that the chromatic aberration with respect to the main wavelength is controlled within + -3.5 μm in the range of the imaging field, which indicates that the optical lens can well correct the peripheral field aberration and the chromatic aberration of each field.

Third embodiment

Referring to fig. 11, a schematic structural diagram of an optical lens 300 according to a third embodiment of the present invention is shown, where the structure of the optical lens 300 in this embodiment is substantially the same as that of the optical lens 100 in the first embodiment.

The parameters related to each lens of the optical lens 300 provided in this embodiment are shown in table 5.

TABLE 5

The surface shape coefficients of the aspherical surfaces of the optical lens 300 in the present embodiment are shown in table 6.

TABLE 6

In the present embodiment, graphs of curvature of field, distortion, chromatic aberration of point on axis, and lateral chromatic aberration of the optical lens 300 are shown in fig. 12, 13, 14, and 15, respectively.

Fig. 12 shows the field curvature of different image heights at the image plane in the tangential direction and the sagittal direction, and it can be seen from the figure that the field curvature in both the tangential direction and the sagittal direction is controlled within ± 0.1mm, which indicates that the lens field curvature correction is good.

Fig. 13 shows F-tan θ distortion of different image heights on the image plane, and it can be seen that the distortion of different image heights on the image plane is controlled within ± 2.5%, indicating that the lens distortion correction is good.

FIG. 14 shows the on-axis spherical aberration, and it can be seen that the chromatic aberration at all wavelengths is controlled within. + -. 0.04mm, indicating that the axial spherical aberration of the lens is also corrected well.

FIG. 15 shows chromatic aberration of each wavelength with respect to the main wavelength for different fields, and it can be seen from the graph that within the range of the imaging field, the chromatic aberration with respect to the main wavelength is controlled within + -1.5 μm, which illustrates that the optical lens can correct the peripheral field aberration and the chromatic aberration of each field well.

Fourth embodiment

Referring to fig. 16, a schematic mechanism diagram of an optical lens 400 according to a fourth embodiment of the present invention is shown, where the optical lens 400 in the present embodiment has a structure substantially the same as that of the optical lens 100 in the first embodiment, and the greatest difference is the central thicknesses of the first lens element and the fifth lens element.

The relevant parameters of each lens in the optical lens 400 in the present embodiment are shown in table 7.

TABLE 7

The surface shape coefficients of the aspherical surfaces of the optical lens 400 in the present embodiment are shown in table 8.

TABLE 8

In the present embodiment, graphs of curvature of field, distortion, chromatic aberration of point on axis, and lateral chromatic aberration of the optical lens 400 are shown in fig. 17, 18, 19, and 20, respectively.

Fig. 17 shows the field curvature of different image heights at the image plane in the tangential direction and the sagittal direction, and it can be seen from the figure that the field curvature in both the tangential direction and the sagittal direction is controlled within ± 0.05mm, which indicates that the lens field curvature correction is good.

Fig. 18 shows F-tan θ distortion of different image heights on the image plane, and it is understood that the distortion of different image heights on the image plane is controlled to be within 2%, which indicates that the lens distortion correction is good.

FIG. 19 shows the on-axis spherical aberration, and it can be seen that the chromatic aberration at all wavelengths is controlled within. + -. 0.02mm, indicating that the axial spherical aberration of the lens is also corrected well.

FIG. 20 shows the chromatic aberration of each wavelength with respect to the main wavelength for different fields, and it can be seen from the graph that the chromatic aberration with respect to the main wavelength is controlled within + -1.2 μm in the imaging field range, which indicates that the optical lens can well correct the fringe field aberration and the chromatic aberration of each field.

Table 9 shows the optical characteristics corresponding to the above four embodiments, which mainly include the effective focal length F, F #, total optical length TTL, and the values corresponding to each conditional expression.

TABLE 9

In summary, the optical lens provided by the invention has at least the following advantages:

(1) through the control to first lens center thickness to and design great diaphragm, make optical lens have higher pixel, can reach great screen and account for than, reduced ghost's risk simultaneously.

(2) Six plastic aspheric lenses with specific refractive power and specific surface types are adopted for matching, the imaging quality of the ultra-high definition pixels is obtained, meanwhile, the miniaturization characteristic of the lens is guaranteed, and the lens can better meet the development trend of the lens.

(3) Compared with a high-definition pixel lens with high price, the invention also provides a mature manufacturing process on the premise of ensuring high pixel and small volume, greatly reduces the manufacturing cost and is more beneficial to market popularization.

Fifth embodiment

Referring to fig. 24, an imaging apparatus 500 according to a fifth embodiment of the present invention is shown, where the imaging apparatus 500 may include an imaging element 510 and an optical lens (e.g., the optical lens 100) in any of the embodiments described above. The imaging element 510 may be a CMOS (Complementary Metal Oxide Semiconductor) image sensor, and may also be a CCD (Charge Coupled Device) image sensor.

The imaging device 500 may be a mobile phone, a tablet, a camera, or any other electronic device with the optical lens mounted thereon.

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

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.