CN210572977U - 2 ten million pixel 25 millimeter FA lens - Google Patents

Abstract

The utility model discloses a 2 ten million pixel 25 millimeter's FA camera lens, include along the optical axis from the object space to the image space first lens group G1 that sets gradually, the diaphragm, second lens group G2 and third lens group G3, first lens group G1 includes along the optical axis from the object space to the first negative meniscus lens L1 that the image space set gradually, first positive biconvex lens L2 and first positive meniscus lens L3, second lens group G2 includes along the optical axis from the object space to the first negative biconcave lens L4 that the image space set gradually, the positive biconvex lens L5 of second, the positive biconvex lens L6 of third and the positive biconvex lens L7 of fourth, third lens group G3 includes along the optical axis from the object space to the positive meniscus lens L8 of second that the image space set gradually and the negative meniscus lens L9 of second. The utility model discloses a 2 ten million pixel 25 millimeters's FA camera lens can solve the image plane of the FA camera lens that exists among the prior art problem that little, resolution ratio are not high to satisfy the market demand.

Description

2 ten million pixel 25 millimeter FA lens

Technical Field

The application belongs to the technical field of optics, and in particular relates to a 2 million pixel 25 millimeter FA lens.

Background

In a machine vision system, the FA lens is the same as human eyes, and mainly has the functions of imaging a target on a photosensitive surface of an image sensor, converting optical signals into electric signals by the photosensitive surface, and directly observing and extracting target characteristic information after the electric signals are transmitted, so that the integral performance of the machine vision system is directly influenced by the imaging quality of the FA lens.

However, most of FA lenses in the current market have image planes of 2/3 inch and resolutions of 800 pixels or less, and thus the market demand is not satisfied.

SUMMERY OF THE UTILITY MODEL

The application aims to provide a 2 million pixel 25mm FA lens, which is used for solving the problems of small image plane and low resolution of the FA lens in the prior art.

In order to achieve the purpose, the technical scheme adopted by the application is as follows:

a2 million pixel 25mm FA lens comprises a first lens group G1, a diaphragm, a second lens group G2 and a third lens group G3 which are arranged in sequence from an object side to an image side along an optical axis;

the first lens group G1 includes a first negative meniscus lens L1, a first positive double convex lens L2, and a first positive meniscus lens L3, which are arranged in this order from the object side to the image side along the optical axis;

the second lens group G2 includes a first negative biconcave lens L4, a second positive biconvex lens L5, a third positive biconvex lens L6, and a fourth positive biconvex lens L7 arranged in this order from the object side to the image side along the optical axis;

the third lens group G3 includes a second positive meniscus lens L8 and a second negative meniscus lens L9 arranged in order from the object side to the image side along the optical axis.

Preferably, the air space between the first lens group G1 and the stop is 12.06mm, the air space between the stop and the second lens group G2 is 3.08mm, and the air space between the second lens group G2 and the third lens group G3 is 3.0 mm.

Preferably, an air space between the first negative meniscus lens L1 and the first positive double convex lens L2 is 6.27mm, and an air space between the first positive double convex lens L2 and the first positive meniscus lens L3 is 0.2 mm.

Preferably, the first negative biconcave lens L4 and the second positive biconvex lens L5 constitute a first cemented lens.

Preferably, the air space between the first cemented lens and the third positive lenticular lens L6 is 1.1mm, and the air space between the third positive lenticular lens L6 and the fourth positive lenticular lens L7 is 2.3 mm.

Preferably, the second positive meniscus lens L8 and the second negative meniscus lens L9 constitute a second cemented lens.

Preferably, the first negative meniscus lens L1 is made of an optical glass material with the model number of H-ZF1, the first positive biconvex lens L2 is made of optical glass with the model number of H-FK61, the first positive meniscus lens L3 is made of optical glass with the model number of H-ZF6, the first negative double concave lens L4 is made of optical glass with the model number of H-ZH6, the second positive biconvex lens L5 is made of optical glass with the model number of H-K9L, the third positive biconvex lens L6 is made of optical glass with the model number of H-LAF3B, the fourth positive biconvex lens L7 is made of optical glass with the model number of H-ZLAF4LA, the second positive meniscus lens L8 is made of optical glass with the model number of H-LAF3B, the second negative meniscus lens L9 is made of optical glass with the model of H-ZF 1.

Preferably, the 2 million pixel 25mm FA lens has an effective focal length of 25mm and a field angle of 38.8 °.

The 2 ten million pixel 25 millimeters's FA camera lens that this application provided has used 9 lenses, through the position and the interval of each camera lens of rational arrangement for optical system can satisfy 1.1 inch 2 ten million pixels, has the distortion step-down simultaneously, and edge illumination is high, the good advantage of imaging quality.

Drawings

FIG. 1 is a schematic diagram of an optical system of a 2 million pixel 25mm FA lens according to an embodiment of the present invention;

FIG. 2 is a speckle diagram of an embodiment of a 2 million pixel 25mm FA lens according to the present application;

FIG. 3 is a MTF graph of an embodiment of a 2 million pixel 25mm FA lens according to the present application;

FIG. 4 is a field curvature and distortion diagram of an embodiment of a 2 million pixel 25mm FA lens according to the present application;

FIG. 5 is a graph of edge luminance of an embodiment of a 2 million pixel 25mm FA lens according to the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. 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 application.

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 application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

As shown in fig. 1, in one embodiment, there is provided a 2-million pixel 25mm FA lens, the 2-million pixel 25mm FA lens including a first lens group G1, a stop, a second lens group G2, and a third lens group G3 arranged in this order from an object side to an image side along an optical axis.

The first lens group G1 includes a first negative meniscus lens L1, a first positive double convex lens L2, and a first positive meniscus lens L3, which are disposed in this order from the object side to the image side along the optical axis.

The second lens group G2 includes a first negative biconcave lens L4, a second positive biconvex lens L5, a third positive biconvex lens L6, and a fourth positive biconvex lens L7, which are arranged in this order from the object side to the image side along the optical axis.

The third lens group G3 includes a second positive meniscus lens L8 and a second negative meniscus lens L9 arranged in this order from the object side to the image side along the optical axis.

It should be noted that the image side is understood as the side where the image is formed, i.e. the side where the focal plane is located in fig. 1; object space is understood to mean the side on which the object is located, i.e. the opposite side of the focal plane in fig. 1. In fig. 1, the direction from the object side to the image side along the optical axis is from the left to the right along the optical axis.

During lens setting, the air space between different lenses will make the lenses have different focal lengths, angles of view, etc., and the lenses with different focal lengths and angles of view often have different usage scenes.

In one embodiment, the air space between the first lens group G1 and the stop is set to 12.06mm, the air space between the stop and the second lens group G2 is set to 3.08mm, and the air space between the second lens group G2 and the third lens group G3 is set to 3.0 mm.

Further, in one embodiment, the air space between the first negative meniscus lens L1 and the first positive double convex lens L2 is set to 6.27mm, and the air space between the first positive double convex lens L2 and the first positive meniscus lens L3 is set to 0.2 mm.

In one embodiment, the first negative biconcave lens L4 and the second positive biconvex lens L5 constitute a first cemented lens.

In one embodiment, the air space between the first cemented lens and the third positive lenticular lens L6 is 1.1mm, and the air space between the third positive lenticular lens L6 and the fourth positive lenticular lens L7 is 2.3 mm.

In one embodiment, the second positive meniscus lens L8 and the second negative meniscus lens L9 constitute a second cemented lens.

The selection of the lens material can adopt glass material, and also can adopt plastic material, the types of the glass material are such as S-LAH55, N-SF15, M-LAC130, etc.; for example, E48R, which is made of plastic.

In one embodiment, in order to obtain higher resolution, the materials of the lenses of the FA lens with 2 million pixels and 25mm are set as follows: the first negative meniscus lens L1 is made of H-ZF1 optical glass, the first positive biconvex lens L2 is made of H-FK61 optical glass, the first positive meniscus lens L3 is made of H-ZF6 optical glass, the first negative biconcave lens L4 is made of H-ZH6 optical glass, the second positive biconvex lens L5 is made of H-K9L optical glass, the third positive biconvex lens L6 is made of H-LAF3B optical glass, the fourth positive biconvex lens L7 is made of H-ZLAF4LA optical glass, the second positive meniscus lens L8 is made of H-LAF3B optical glass, and the second negative meniscus lens L9 is made of H-ZF1 optical glass.

With reference to the above embodiments, the preferred parameters for obtaining the FA lens with 2 million pixels and 25mm of the present application are shown in table 1 below.

TABLE 1 optical element parameter table

In table 1, L1 denotes a first negative meniscus lens L1, the same holds true; s1 to S6 and S8 to S17 represent mirror surfaces of the lenses L1 to L9 from left to right, for example, S1 represents a surface of the lens L1 facing the object side, S2 represents a surface of the lens L1 facing the image side, and the same holds true for the rest; r is the paraxial radius of curvature of the lens mirror.

The optical structure of the FA lens constituted by the lenses shown in table 1 has the following optical indices:

(1) focal length: f ═ 25 mm;

(2) field angle range: 38.8 degrees;

(3) relative pore diameter: 1: 2.8;

(4) distortion: -0.2%;

(5) working temperature: -20 ℃ to +50 ℃;

(6) edge illuminance: 0.76

(7) Working distance: 0.1m to infinity.

The following test was carried out for the FA lens constituted by the lenses shown in table 1, and the test results are shown below:

as shown in fig. 2, the image is a spot diagram of an FA lens, and the Root Mean Square (RMS) value of the optical system is not more than 2.1um and less than 2.5um of the pixel size, so that the imaging requirement is met.

As shown in fig. 3, the MTF of the FA lens is shown, the MTF of the edge field of the optical system is greater than 0.3 under the characteristic frequency (200lp/mm), the MTF of the center field of the optical system is greater than 0.43, and the imaging quality is good.

As shown in fig. 4, which is a field curvature and distortion diagram of the FA lens, the distortion of the entire field of view of the optical system is less than 0.2%, and the distortion is low.

As shown in fig. 5, which is a graph of the edge illumination of the FA lens, the edge illumination of the optical system is greater than 0.76, and the edge illumination is high.

From the above test results, the FA lens with 2 million pixels and 25mm provided by this embodiment uses 9 lenses, and by reasonably arranging the positions and the distances of the lenses, the optical system can satisfy 1.1 inch and 2 million pixels, and has the advantages of low distortion, high edge illumination and excellent imaging quality.

The test step is a conventional step of lens detection, and is not described herein again.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

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

Claims (8)

1. A2 million pixel 25mm FA lens, characterized in that the 2 million pixel 25mm FA lens comprises a first lens group (G1), a diaphragm, a second lens group (G2) and a third lens group (G3) which are arranged in sequence from an object side to an image side along an optical axis;

the first lens group (G1) includes a first negative meniscus lens (L1), a first positive biconvex lens (L2), and a first positive meniscus lens (L3) arranged in this order from the object side to the image side along the optical axis;

the second lens group (G2) includes a first negative biconcave lens (L4), a second positive biconvex lens (L5), a third positive biconvex lens (L6), and a fourth positive biconvex lens (L7) arranged in this order from the object side to the image side along the optical axis;

the third lens group (G3) includes a second positive meniscus lens (L8) and a second negative meniscus lens (L9) that are arranged in order from the object side to the image side along the optical axis.

2. The 2 million pixel 25mm FA lens of claim 1, wherein the air space between the first lens group (G1) and the stop is 12.06mm, the air space between the stop and the second lens group (G2) is 3.08mm, and the air space between the second lens group (G2) and the third lens group (G3) is 3.0 mm.

3. The 2 million pixels by 25mm FA lens according to claim 1, wherein an air space between the first negative meniscus lens (L1) and the first positive biconvex lens (L2) is 6.27mm, and an air space between the first positive biconvex lens (L2) and the first positive meniscus lens (L3) is 0.2 mm.

4. The 2 million pixels by 25mm FA lens according to claim 1, wherein the first negative double concave lens (L4) and the second positive double convex lens (L5) constitute a first cemented lens.

5. The 2 million-pixel 25mm FA lens according to claim 4, wherein an air space between the first cemented lens and a third positive lenticular lens (L6) is 1.1mm, and an air space between the third positive lenticular lens (L6) and a fourth positive lenticular lens (L7) is 2.3 mm.

6. The 2 million pixels by 25mm FA lens according to claim 1, wherein the second positive meniscus lens (L8) and the second negative meniscus lens (L9) constitute a second cemented lens.

7. The FA lens with 25mm 2 million pixels according to claim 1, wherein the first negative meniscus lens (L1) is made of an optical glass material with the type H-ZF1, the first positive biconvex lens (L2) is made of an optical glass material with the type H-FK61, the first positive meniscus lens (L3) is made of an optical glass material with the type H-ZF6, the first negative biconcave lens (L4) is made of an optical glass material with the type H-ZH6, the second positive biconvex lens (L5) is made of an optical glass material with the type H-K9L, the third positive biconvex lens (L6) is made of an optical glass material with the type H-LAF3B, the fourth positive biconvex lens (L7) is made of an optical glass material with the type H-ZLAF4LA, and the second positive meniscus lens (L8) is made of an optical glass material with the type H-LAF3B, the second negative meniscus lens (L9) is made of optical glass with the model of H-ZF 1.

8. The 2 million pixels by 25 millimeters FA lens of claim 1, wherein the 2 million pixels by 25 millimeters FA lens has an effective focal length of 25mm and a field angle of 38.8 °.

Images