CN211979310U

CN211979310U - Compact high-definition matching lens

Info

Publication number: CN211979310U
Application number: CN202020487643.4U
Authority: CN
Inventors: 吴强华; 胡长涛; 张福美
Original assignee: Jiangxi Telaisi Optical Co ltd
Current assignee: Jiangxi Telaisi Optical Co ltd
Priority date: 2020-04-07
Filing date: 2020-04-07
Publication date: 2020-11-20
Anticipated expiration: 2030-04-07

Abstract

The utility model discloses a compact high definition matches camera lens includes from the object plane to image planes along the optical axis in proper order: the lens comprises a first lens, a second lens, a third lens, a diaphragm, a fourth lens, a fifth lens and a sixth lens; the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the focal length of the sixth lens is f6, which satisfy the relationship: 6.43< f2<6.86, -4.86< (f3/f4) < -2.37, 1.24< (f6/f5) < 3.15. The utility model discloses constitute by six lenses, the total length of camera lens TTL is 20mm, and compact structure can match 1/3 "and following target surface SENSOR, and resolution ratio reaches 5 megapixels, and CRA <15, can have fine matching with the chip, improves the imaging quality and the stability of camera lens.

Description

Compact high-definition matching lens

Technical Field

The utility model relates to an optical system for record appearance and the module of making a video recording of using thereof, especially a compact high definition match camera lens.

Background

With the development of the times, the application of a driving recording and safe driving system is more and more popular, and the requirements on the industry are more and more strict. And many of the camera module markets applied to driving recording and safe driving are in low-end technologies, for example, the resolution is not high, the resolution is high but unstable and the field angle is not large enough, and many of the technologies are not well matched with a chip because the CRA angle is too large.

Therefore, a compact high-definition matching lens which is compatible with wide-angle high-definition and has a large matching with a chip is needed to be designed.

Disclosure of Invention

In order to overcome the defects, the utility model aims to provide a compact high definition matches camera lens.

In order to achieve the purpose, the utility model is implemented according to the following technical scheme:

the utility model provides a compact high definition matches camera lens, includes from the object plane to image plane along the optical axis in proper order: the lens comprises a first lens, a second lens, a third lens, a diaphragm, a fourth lens, a fifth lens and a sixth lens; the object plane side of the first lens is a convex surface, and the image plane side of the first lens is a concave surface; the object side of the second lens is a convex surface, and the image side of the second lens is a convex surface; the object plane side of the third lens is a concave surface, and the image plane side of the third lens is a concave surface; the object plane side of the fourth lens is a concave surface, and the image plane side of the fourth lens is a convex surface; the object plane side of the fifth lens is a convex surface, and the image plane side of the fifth lens is a convex surface; the object plane side of the sixth lens is a concave surface, and the image plane side of the sixth lens is a convex surface; the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the focal length of the sixth lens is f6, which satisfy the following relations: 6.43< f2<6.86, -4.86< (f3/f4) < -2.37, 1.24< (f6/f5) < 3.15.

Further, the second lens and the third lens are a group of cemented lenses.

Further, the fifth lens and the sixth lens are a group of cemented lenses.

Further, the field angle 2 omega of the compact high-definition matching lens is between 60 degrees and 65 degrees.

Further, a protective glass is provided on the side of the sixth transmission mirror surface.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses constitute by six lenses, the total length of camera lens TTL is 20mm, and compact structure can match 1/3 "and following target surface SENSOR, and resolution ratio reaches 5 megapixels, and CRA <15, can have fine matching with the chip, improves the imaging quality and the stability of camera lens.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.

Fig. 1 is a schematic view of a lens structure according to an embodiment of the present invention;

fig. 2 is a first analysis diagram according to an embodiment of the present invention;

fig. 3 is a second analysis diagram according to an embodiment of the present invention;

fig. 4 is a field curvature diagram of an embodiment of the present invention;

FIG. 5 is a diagram of F-THETA distortion according to an embodiment of the present invention;

fig. 6 is a relative illuminance diagram according to an embodiment of the present invention;

fig. 7 is a CRA angle diagram of the angle of view according to the embodiment of the present invention.

Detailed Description

The invention will be further described with reference to the drawings and specific embodiments, illustrative embodiments and description of which are provided herein to explain the invention, but not as a limitation thereof.

As shown in fig. 1, the compact high-definition matching lens sequentially includes, from an object plane to an image plane along an optical axis: a first lens E1, a second lens E2, a third lens E3, a stop ST, a fourth lens E4, a fifth lens E5, a sixth lens E6; the object surface side of the first lens E1 is a convex surface, and the image surface side is a concave surface; the second lens object E2 has a convex surface on the surface side and a convex surface on the image surface side; the object plane side of the third lens E3 is a concave surface, and the image plane side is a concave surface; the object surface side of the fourth lens E4 is a concave surface, and the image surface side is a convex surface; the fifth lens E5 has a convex object surface side and a convex image surface side; the object plane side of the sixth lens E6 is a concave surface, and the image plane side is a convex surface; the focal length of the second lens E2 is f2, the focal length of the third lens E3 is f3, the focal length of the fourth lens E4 is f4, the focal length of the fifth lens E5 is f5, and the focal length of the sixth lens E6 is f6, which satisfy the following relations: 6.43< f2<6.86, -4.86< (f3/f4) < -2.37, 1.24< (f6/f5) < 3.15.

In some embodiments, the second lens E2 and the third lens E3 are a set of cemented lenses.

In some embodiments, the fifth lens E5 and the sixth lens E6 are a set of cemented lenses.

In some embodiments, the field angle 2 ω of the compact high-definition matched lens is between 60 ° and 65 °.

In some embodiments, the image plane side of the sixth lens E6 is further provided with a protective glass E7.

Wherein: as shown in fig. 1, the object surface side of the first lens E1 is S1, the image surface side is S2, the object surface side of the second lens E2 is S3, the cemented surface between the second lens E2 and the third lens E3 is S4, the image surface side of the third lens E3 is S5, the object surface side of the fourth lens E4 is S6, the image surface side is S7, the object surface side of the fifth lens E5 is S8, the cemented surface between the fifth lens E5 and the sixth lens E6 is S9, and the image surface side of the sixth lens E6 is S10.

To verify the optical performance of the superlarge angle low-cost optical device of the present embodiment, when the working distance is infinity, the total focal length f of the lens is 6mm, FNO is 2.0, and the parameters of the field angle FOV is 62 ° are listed in table 1.

TABLE 1

In the above table, Index is a refractive Index, Radius is a curvature Radius, ABB is an ABB number, and focal lengths of the first to sixth lenses are f1 to f6 in this order, which can be obtained from table 1:

f2 ═ 6.65, which satisfies the design of 6.43< f2<6.86 described above; (f3/f4) — 59.14/16.25 ═ 3.63938462, which satisfies the design of-4.86 < (f3/f4) < -2.37 described above; (f6/f5) ═ 33.22/19.86 ═ 1.67270896, which satisfies the design of 1.24< (f6/f5) <3.15 above.

As shown in fig. 2 and fig. 3, fig. 2 and fig. 3 are Modulation Transfer Function (MTF) value graphs of the present embodiment, which are based on the parameters in table 1, and the MTF value graph is defined to be greater than 0 and less than 1 based on the measurement of the quality such as the most important resolution of the optical lens, and the MTF value is closer to 1 in the field of the technology, which indicates that the performance of the lens is more excellent, i.e. the resolution is higher; the variable is the spatial frequency, namely how many lines can be presented in a range of one mm to measure the spatial frequency, and the unit is expressed by lp/mm; a fixed high frequency (e.g., 300lp/mm) curve represents the lens resolution characteristic, and the higher this curve, the higher the lens resolution, and the ordinate is the MTF value. The distance from the center of the image field to the measuring point can be set on the abscissa, the lens is of a symmetrical structure taking the optical axis as the center, the change rule of the imaging quality from the center to each direction is the same, and due to the influence of factors such as aberration and the like, the farther the distance between a certain point in the image field and the center of the image field is, the MTF value generally has a descending trend. Therefore, the distance from the center of the image field to the edge of the image field is taken as the abscissa, and the imaging quality of the edge of the lens can be reflected; in addition, at a position deviated from the center of the image field, MTF values measured by the sinusoidal gratings of the line in the tangential direction and the line in the radial direction are different; the MTF curve produced by a line parallel to the diameter is called the sagittal curve, denoted s (sagittal), and the MTF curve produced by a line parallel to the tangent is called the meridional curve, denoted t (meridian); therefore, there are generally two MTF curves, i.e., an S curve and a T curve, and in fig. 2 and 3, there are a plurality of MTF variation curves using the distance from the center of the image field to the edge of the image field as the abscissa, which reflects that the lens system has a higher resolving power and a resolution of more than six million pixels.

Fig. 2-6 sequentially show a first analytical diagram, a second analytical diagram, a field curvature diagram, a distortion diagram, and a relative illumination diagram of the compact high-definition matched lens of the present embodiment when the working distance is infinity.

As shown in FIG. 4, the closer the curve is to the y-axis, the smaller the field curvature, the control of the meridional field curvature value within the range of-0.02-0.05 mm, and the control of the sagittal field curvature value within the range of-0.02-0.05 mm. As shown in fig. 5, in which the optical distortion rate is controlled within the range of-10%. As shown in fig. 6, where the relative illuminance is greater than 76%, as shown in fig. 7, CRA is less than 15 ° when the compact high-definition matching lens of the present embodiment is matched with the 1/3 ″ chip.

The technical scheme of the utility model is not limited to the restriction of above-mentioned specific embodiment, all according to the utility model discloses a technical scheme makes technical deformation, all falls into within the protection scope of the utility model.

Claims

1. The utility model provides a compact high definition matches camera lens, includes from the object plane to image plane along the optical axis in proper order: the lens comprises a first lens, a second lens, a third lens, a diaphragm, a fourth lens, a fifth lens and a sixth lens; the method is characterized in that: the object plane side of the first lens is a convex surface, and the image plane side of the first lens is a concave surface; the object side of the second lens is a convex surface, and the image side of the second lens is a convex surface; the object plane side of the third lens is a concave surface, and the image plane side of the third lens is a concave surface; the object plane side of the fourth lens is a concave surface, and the image plane side of the fourth lens is a convex surface; the object plane side of the fifth lens is a convex surface, and the image plane side of the fifth lens is a convex surface; the object plane side of the sixth lens is a concave surface, and the image plane side of the sixth lens is a convex surface; the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the focal length of the sixth lens is f6, which satisfy the following relations: 6.43< f2<6.86, -4.86< (f3/f4) -2.37, 1.24< (f6/f5) < 3.15; the field angle 2 omega of the compact high-definition matching lens is between 60 and 65 degrees; the total lens length TTL is 20 mm.

2. The compact high-definition matched lens of claim 1, wherein: the second lens and the third lens are a group of cemented lenses.

3. The compact high-definition matched lens of claim 1, wherein: the fifth lens and the sixth lens are a group of cemented lenses.

4. The compact high-definition matched lens according to any one of claims 1 to 3, wherein a protective glass is further arranged on the side of the sixth transmission image surface.