阅读说明：本技术 一种超广角超大光圈光学镜头 (Super wide angle super large light ring optical lens ) 是由 吴强华 胡长涛 张福美 于 2019-09-30 设计创作，主要内容包括：本发明涉及光学成像技术领域,尤其涉及一种超广角超大光圈光学镜头,沿光轴方向从物侧到像侧依次包括：光焦度为负的第一弯月型透镜,光焦度为负的第一双凹透镜,光焦度为正的第一胶合透镜组,光焦度为正的第一双凸透镜,光焦度为负的第二胶合透镜组,光焦度为正的第三胶合透镜组,光焦度为正的第四双凸透镜,光焦度为正的第五弯月透镜,滤光片和像面。通过采用合理光焦度分配的具有特定结构形状的透镜组成的超广角超大光圈光学镜头,可以在实现超大光圈情况下兼顾超广角实现超广角和4K像素级解像力。(The invention relates to the technical field of optical imaging, in particular to an ultra-wide-angle super-large aperture optical lens, which sequentially comprises the following components from an object side to an image side along an optical axis direction: the optical lens comprises a first meniscus lens with negative focal power, a first biconcave lens with negative focal power, a first cemented lens group with positive focal power, a first biconvex lens with positive focal power, a second cemented lens group with negative focal power, a third cemented lens group with positive focal power, a fourth biconvex lens with positive focal power, a fifth meniscus lens with positive focal power, an optical filter and an image plane. The ultra-wide-angle ultra-large aperture optical lens formed by the lens with the specific structural shape and reasonable optical focal length distribution can realize ultra-wide angle and 4K pixel resolution under the condition of realizing the ultra-large aperture.)

1. The utility model provides an ultra wide angle super large aperture optical lens which characterized in that: the image pickup device includes, in order from an object side to an image side in an optical axis direction: the optical lens comprises a first meniscus lens with negative focal power, a first biconcave lens with negative focal power, a first cemented lens group with positive focal power, a first biconvex lens with positive focal power, a second cemented lens group with negative focal power, a third cemented lens group with positive focal power, a fourth biconvex lens with positive focal power, a fifth meniscus lens with positive focal power, an optical filter and an image surface;

the effective focal length of the second cemented lens group and the effective focal length of the ultra-wide-angle ultra-large aperture optical lens meet a first set relationship, and the effective focal length of the third cemented lens group and the effective focal length of the ultra-wide-angle ultra-large aperture optical lens meet a second set relationship;

wherein the first setting relationship is: 6.75 < | fB/f | < 7.25,

the second setting relationship is: 16.8 < | fC/f | < 17.8,

the ultra-wide-angle ultra-large aperture optical lens meets the following conditional expression: l/h <4.3

Wherein: l represents the total length of the ultra-wide-angle ultra-large aperture optical lens, and h represents the size of the image plane;

fB represents the effective focal length of the second cemented lens group, fC represents the effective focal length of the third cemented lens group, and f represents the effective focal length of the ultra-wide-angle ultra-large aperture optical lens.

2. The ultra-wide angle ultra-large aperture optical lens of claim 1, wherein: the surface of the first meniscus lens facing the object side is a convex surface.

3. The ultra-wide angle ultra-large aperture optical lens of claim 1, wherein: the first cemented lens group includes: the second meniscus lens with positive focal power faces the image measurement, the third meniscus lens with negative focal power faces the image measurement; the second meniscus lens and the third meniscus lens are seamlessly cemented to form a first cemented lens group.

4. The ultra-wide angle ultra-large aperture optical lens of claim 1, wherein: the second cemented lens group includes: a second biconvex lens with positive focal power and a second biconvex lens with negative focal power; the second biconvex lens and the second biconcave lens are seamlessly cemented to form a second cemented lens group.

5. The ultra-wide angle ultra-large aperture optical lens of claim 1, wherein: the third cemented lens group includes: the focal power of the third biconvex lens is positive, the focal power of the fourth meniscus lens is negative, and the convex surface faces the image side; the third biconvex lens and the fourth meniscus lens are seamlessly cemented to form a third cemented lens group.

6. The ultra-wide angle ultra-large aperture optical lens of claim 1, wherein: the abbe coefficients of the second biconvex lens, the third biconvex lens and the fourth biconvex lens are all larger than 65.

7. The ultra-wide angle ultra-large aperture optical lens of claim 1, wherein: the refractive index of the third meniscus lens is larger than 1.9.

8. The ultra-wide angle ultra-large aperture optical lens of claim 1, wherein: the refractive index of the first biconvex lens and the refractive index of the fourth meniscus lens are both greater than 2.0.

Technical Field

The invention relates to the technical field of optical imaging, in particular to an ultra-wide-angle super-large aperture optical lens.

Background

In the security field, a network camera is a common device in a security system, a lens is a main constituent part of the network camera, the performance of the lens directly affects the imaging quality and the imaging field of view, and as the technical index requirements of the security system are continuously improved, how to improve the imaging field of view at night and under low light level conditions becomes a big subject of the security industry, the aperture of an ultra-wide-angle lens in the existing scheme is about 2.0, and the field angle of the ultra-wide-aperture lens in the existing scheme is below 100 degrees. However, the large aperture lens manufactured by the conventional structure design has a large field angle and a low general resolution because the large aperture lens has aberration which is more difficult to correct and brings a larger imaging field of view due to an ultra-wide angle.

Disclosure of Invention

The invention aims to overcome the defects of the technology and provide an ultra-wide-angle and ultra-large aperture optical lens.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides an ultra wide angle super large aperture optical lens which characterized in that: the image pickup device includes, in order from an object side to an image side in an optical axis direction: the optical lens comprises a first meniscus lens with negative focal power, a first biconcave lens with negative focal power, a first cemented lens group with positive focal power, a first biconvex lens with positive focal power, a second cemented lens group with negative focal power, a third cemented lens group with positive focal power, a fourth biconvex lens with positive focal power, a fifth meniscus lens with positive focal power, an optical filter and an image surface;

the effective focal length of the second cemented lens group and the effective focal length of the ultra-wide-angle ultra-large aperture optical lens meet a first set relationship, and the effective focal length of the third cemented lens group and the effective focal length of the ultra-wide-angle ultra-large aperture optical lens meet a second set relationship;

wherein the first setting relationship is: 6.75 < | fB/f | < 7.25,

the second setting relationship is: 16.8 < | fC/f | < 17.8,

the ultra-wide-angle ultra-large aperture optical lens meets the following conditional expression: l/h <4.3

Wherein: l represents the total length of the ultra-wide-angle ultra-large aperture optical lens, and h represents the size of the image plane;

fB represents the effective focal length of the second cemented lens group, fC represents the effective focal length of the third cemented lens group, and f represents the effective focal length of the ultra-wide-angle ultra-large aperture optical lens.

Preferably, a surface of the first meniscus lens facing the object side is a convex surface.

Preferably, the second meniscus lens with positive optical power has a convex surface facing the image side, and the third meniscus lens with negative optical power has a convex surface facing the image side; the second meniscus lens and the third meniscus lens are seamlessly cemented to form a first cemented lens group.

Preferably, the second biconvex lens has positive optical power and the second biconvex lens has negative optical power; the second biconvex lens and the second biconcave lens are seamlessly cemented to form a second cemented lens group.

Preferably, the focal power of the third biconvex lens is positive, the focal power of the fourth meniscus lens is negative, and the convex surface faces the image side; the third biconvex lens and the fourth meniscus lens are seamlessly cemented to form a third cemented lens group.

Preferably, abbe numbers of the second biconvex lens, the third biconvex lens and the fourth biconvex lens are all greater than 65.

Preferably, the refractive indices of the third meniscus lenses are each greater than 1.9.

Preferably, the refractive index of the first biconvex lens and the refractive index of the fourth meniscus lens are both greater than 2.0.

Compared with the prior art, the ultra-wide-angle and ultra-large-aperture optical lens has the advantages that the ultra-wide-angle and 4K pixel resolution can be realized under the condition of realizing the ultra-large aperture by adopting the ultra-wide-angle and ultra-large-aperture optical lens formed by the lenses with the specific structural shapes and distributed reasonably optical focuses. The ultra-wide angle and the ultra-large aperture are considered, and the maximum field angle reaches 150-160 degrees. The aperture is larger, F NO. reaches 0.9, clear imaging can be realized at night without light supplement, and the low-light effect is better. The total length is less than 30 mm. The resolution is higher, and the device can be matched with a 4K chip (more than eight million pixels). In addition, the ultra-wide-angle ultra-large aperture optical lens also has lower cost. By adopting the structural shape of the optical lens system provided by the invention, parameters such as Abbe coefficients of optical glass materials are well matched with imaging conditions, so that spherical aberration, coma aberration, astigmatism, field curvature, chromatic aberration of magnification and position chromatic aberration of the lens system are well corrected, the use requirement of a 4K camera is met, and the optical lens system is compact in structure and small in overall dimension. In addition, all optical lenses adopt a spherical surface design, the cold machining process performance of the lenses is good, the cost of glass materials is low, the price of finished lenses is also low, and the yield of mass production is high; but wide application in security protection control field.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a 300lp/mmMTF analysis graph according to an embodiment of the present invention;

FIG. 3 is a 160lp/mmMTF analysis diagram according to an embodiment of the present invention.

Detailed Description

The following detailed description of the preferred embodiments will be made with reference to the accompanying drawings. As shown in fig. 1, an ultra-wide-angle super-large aperture optical lens sequentially includes, from an object side to an image side along an optical axis: the optical lens comprises a first meniscus lens 1 with negative focal power, a first biconcave lens 2 with negative focal power, a first cemented lens group A with positive focal power, a first biconvex lens 5 with positive focal power, a second cemented lens group B with negative focal power, a third cemented lens group C with positive focal power, a fourth biconvex lens 10 with positive focal power, a fifth meniscus lens 11 with positive focal power, an optical filter and an image plane; the surface of the first meniscus lens facing the object side is a convex surface.

In the ultra-wide-angle super-large aperture optical lens provided by the embodiment of the present invention, as shown in fig. 1, the first cemented lens group a includes: a second meniscus lens 3 with positive focal power, the convex surface facing the image side; a third meniscus lens 4 with negative focal power, the convex surface facing the image side; the second meniscus lens and the third meniscus lens are seamlessly cemented to form a first cemented lens group a. Because the second meniscus lens 3 with the positive focal power has negative chromatic aberration, and the third meniscus lens 4 with the negative focal power has positive chromatic aberration, the second meniscus lens 3 with the positive focal power and the third meniscus lens 4 with the negative focal power are seamlessly cemented to form the first cemented lens group so as to realize the mutual compensation of chromatic aberration, eliminate chromatic aberration, optimize the imaging definition, improve the image quality of an optical system and improve the resolution.

In the ultra-wide-angle super-large aperture optical lens provided by the embodiment of the present invention, as shown in fig. 1, the second cemented lens group B includes: a second biconvex lens 6 having positive focal power; a second biconcave lens 7 having negative optical power; the second biconvex lens 6 and the second biconcave lens 7 are seamlessly cemented to form a second cemented lens group B. The second cemented lens group has similar action with the first cemented lens group, and is used for chromatic aberration mutual compensation, eliminating chromatic aberration, optimizing imaging definition, improving image quality of an optical system and improving resolution.