CN211979313U

CN211979313U - Compact short-focus high-definition lens

Info

Publication number: CN211979313U
Application number: CN202020488246.9U
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 short burnt high definition 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 object side of the first lens is a convex surface, and the image 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 concave surface; the object plane side of the third lens is a convex surface, and the image plane side of the third lens is a convex 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 third lens is f3, the focal length of the fourth lens is f4, and the relationship: 1.46< f3<3.46, 1.84< (f4/f3) < 2.84. Compared with the prior art, the utility model discloses constitute by six lenses, camera lens total length TTL 13.5mm, compact structure helps very big to reducing complete machine thickness volume, and resolution ratio is high.

Description

Compact short-focus high-definition 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 short burnt high definition camera lens of compact.

Background

Along with the application and popularization of the automobile safe driving system, the vehicle-mounted camera module is also commonly applied. And the camera module applied to the driving record is required to realize miniaturization and high resolution, and the defects of overlong length, overlong focal length, excessive lenses and complex structure generally exist in the conventional optical system or camera module for meeting the requirements.

For this reason, it is necessary to design a compact short-focus high-definition lens.

Disclosure of Invention

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

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

the utility model provides a compact short burnt high definition 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 concave surface; the object plane side of the third lens is a convex surface, and the image plane side of the third lens is a convex 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 third lens is f3, the focal length of the fourth lens is f4, and the relationship: 1.46< f3<3.46, 1.84< (f4/f3) < 2.84.

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

Further, the optical total length ttl of the compact short-focus high-definition lens satisfies the following condition: and the ttl is more than or equal to 13mm and less than or equal to 14 mm.

Preferably, the total optical length ttl of the compact short-focus high-definition lens is 13.5 mm.

Further, the field angle 2 ω of the compact short-focus high-definition lens is between 95 ° and 105 °.

Furthermore, two layers of protective glass are sequentially arranged on the image surface side of the sixth lens.

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

the utility model discloses constitute by six lenses, camera lens total length TTL 13.5mm, compact structure helps very big, and resolution ratio is high to reducing complete machine thickness volume.

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.

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 short-focus high-definition 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 object surface side of the second lens E2 is a convex surface, and the image surface side is a concave surface; the object surface side of the third lens E3 is a convex surface, and the image surface side is a convex 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 third lens E3 is f3, the focal length of the fourth lens E4 is f4, and the relationship: 1.46< f3<3.46, 1.84< (f4/f3) < 2.84.

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

In some embodiments, the total optical length ttl of the compact short-focus high-definition lens satisfies the following condition: 13mm and ttl are respectively less than or equal to 14mm, preferably 13.5 mm.

In some embodiments, the field angle 2 ω of the compact short-focus high-definition lens is between 95 ° and 105 °.

In some embodiments, two layers of protective glass, E7 and E8, are sequentially arranged on the image plane side of the sixth lens E6.

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 image surface side is S4, the object surface side of the third lens E3 is S5, the image surface side is S6, the object surface side of the fourth lens E4 is S7, the image surface side is S8, the object surface side of the fifth lens E5 is S9, the cemented surface of the fifth lens E5 and the sixth lens E6 is S10, and the image surface side of the sixth lens E6 is S11.

To verify the optical performance of the superlarge angle low-cost optical device of this embodiment, at an infinite working distance, the total focal length f of the lens is 2.46mm, FNO is 2.8, and the parameters of the field angle FOV is 97.2 ° 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:

f3 ═ 2.53, which satisfies the design of 1.46< f3<3.46 above; (f4/f3) ═ 5.84/2.53 ═ 2.3083004, which satisfies the design of 1.84< (f4/f3) <2.84 described 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 resolution and a resolution of more than five 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 short-focus high-definition 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-0.04-0.03 mm, and the control of the sagittal field curvature value within the range of-0.04-0.03 mm. As shown in fig. 5, in which the optical distortion is controlled to be within-30%. As shown in fig. 6, where the relative illuminance is greater than 83%.

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 short burnt high definition 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 concave surface; the object plane side of the third lens is a convex surface, and the image plane side of the third lens is a convex 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 third lens is f3, the focal length of the fourth lens is f4, and the relationship: 1.46< f3<3.46, 1.84< (f4/f3) < 2.84.

2. The compact short-focus high-definition lens according to claim 1, wherein: the fifth lens and the sixth lens are a group of cemented lenses.

3. The compact short-focus high-definition lens according to claim 1, wherein: the total optical length ttl of the compact short-focus high-definition lens meets the following condition: and the ttl is more than or equal to 13mm and less than or equal to 14 mm.

4. The compact short-focus high-definition lens according to claim 3, wherein: the total optical length ttl of the compact short-focus high-definition lens is 13.5 mm.

5. The compact short-focus high-definition lens according to claim 1, wherein: the field angle 2 omega of the compact short-focus high-definition lens is between 95 and 105 degrees.

6. The compact short-focus high-definition lens according to any one of claims 1 to 5, wherein two layers of protective glass are arranged on the image plane side of the sixth lens in sequence.