CN106646837B

CN106646837B - Fisheye lens

Info

Publication number: CN106646837B
Application number: CN201710167949.4A
Authority: CN
Inventors: 范治江; 李伟
Original assignee: Usblend Beijing Technology Co ltd
Current assignee: Kaimu Zhongshan Electronic Technology Co Ltd
Priority date: 2016-03-31
Filing date: 2017-03-21
Publication date: 2019-01-29
Anticipated expiration: 2037-03-21
Also published as: CN106646837A

Abstract

The invention provides a novel fisheye lens. The fisheye lens has an eight-group ten-lens structure, wherein two bonded lens groups are included; the first bonding lens group is formed by bonding a fourth lens and a fifth lens along the direction of an optical axis from an object to an imaging end, and the second bonding lens group is formed by bonding a sixth lens and a seventh lens. This fisheye lens makes the correction to the purple fringed, has optimized optical structure, and the dispersion from high to low through ten lenses is mutually arranged, has great improvement to the chromatic aberration, corrects the purple fringed after the formation of image for the purple fringed scope of formation of image than the first edition product is littleer.

Description

Fish eye lens

Technical field

The present invention relates to a kind of fish eye lenses.

Background technique

Fish eye lens belongs to one of bugeye lens special lens, its visual angle usually is out what human eye can be seen Range.Therefore, there is very big difference in the scene of fish eye lens and the real world in human eye.Human eye is seen in real life The world be well-regulated fixed form, and by fish eye lens generate picture effect then there are various distortion.Ordinary circumstance Under, fish eye lens can be understood as the bugeye lens for not doing pattern distortion correction, this feature makes fish-eye visual angle It may be designed to close or equal to 180 °.

Due to not doing distortion correction, fish eye lens structure can be to avoid using special lens, such as aspherical lens, low color The eyeglass of eyeglass, glasses lens plated contour cost material or processing technology is dissipated, this has fish eye lens relative to bugeye lens More cheap manufacturing cost, performance be substantially meet fish-eye optical system using spherical mirror It is required that.

Into after the digital age, digital camera in shooting process, since subject light contrast is larger, bloom with The color spot that low smooth position intersection occurs, mostly purple (or other colors), are referred to as " purple boundary ".In the film epoch, purple boundary Problem is almost not counting problem.But to the digital age, purple boundary is just at a distinct issues.

Purple boundary Producing reason be it is various, camera lens to the control of dispersion be reduce purple boundary an important means.By In the architectural characteristic of bugeye lens inherently, exist because lens design causes the luminous flux at picture centre and edge uneven It is even, cause purple boundary phenomenon more obvious.

Therefore, the digital age needs a fish eye lens that is low in cost and can optimizing purple boundary.

Summary of the invention:

The purpose of the present invention is to provide a kind of novel fish eye lenses.

The fish eye lens has eight groups of ten lens arrangements, wherein including two cemented lens groups；Along its optical axis direction By object to imaging end, the first cemented lens group is bonded by the 4th and the 5th lens, second cemented lens Group is bonded by the 6th and the 7th lens.

Above-mentioned the second cemented lens of fish eye lens group effective focal length is 15mm.

The six-element lens be refractive index 1.78-1.90 glass lens, abbe number 20-30, focal length 8mm, R1 curvature radius is 4-6, and R2 curvature radius is -6~-10.The six-element lens refractive index preferably 1.83, dispersion system Number preferably 26.

7th lens are refractive index 1.78-1.95 glass lens；Its abbe number is 20-30, and focal length is -8mm, R1 curvature radius is 3-6；R2 curvature radius is -10~-15.7th index of refraction in lens preferably 1.80, dispersion Coefficient is preferably 25.

Glass lens of the 8th lens of the fish eye lens for refractive index 1.78-1.95, abbe number 20-30, Focal length is -10mm, and R1 curvature radius is 15-20, and R2 curvature radius is 3-6.8th lens are preferably refractive index 1.88 glass lens, abbe number are preferably 25.

The first cemented lens of fish eye lens group effective focal length is 12mm.

4th lens be refractive index 1.78-1.95 glass lens, abbe number 20-30, focal length for- The face 10mm, R1 is plane, and R2 curvature radius is 3-6.4th index of refraction in lens preferably 1.86, abbe number is preferred It is 25.

5th lens be refractive index 1.78-1.95 glass lens, abbe number 20-30, focal length 4mm, R1 curvature radius is 3-6, and R2 curvature radius is -10~-15.5th index of refraction in lens preferably 1.90, dispersion Coefficient is preferably 25.

First lens of the fish eye lens are the glass lens of refractive index 1.5-1.6, and abbe number 70-75 is burnt Away from for -15mm, R1 curvature radius is 15-18, and R2 curvature radius is 8-10.First index of refraction in lens is preferred 1.55, abbe number is preferably 72.

Glass lens of second lens of the fish eye lens for refractive index 1.75-1.90, abbe number 40-50, Focal length is -8mm, and R1 curvature radius is 15-20, and R2 curvature radius is 3-6.Second index of refraction in lens is preferred 1.80, abbe number is preferably 45.

The fish eye lens third piece lens are the glass lens of refractive index 1.80-1.85, and abbe number 30-35 is burnt Away from for -7mm, R1 curvature radius is that -10~-12, R2 curvature radius is 4-10.The third piece index of refraction in lens is preferred 1.82, abbe number is preferably 34.

Glass lens of the 9th lens of the fish eye lens for refractive index 1.70-1.80, abbe number 50-60, Focal length is 7mm, and R1 curvature radius is 15-20, and R2 curvature radius is -10~-15.9th index of refraction in lens is preferred 1.75, abbe number is preferably 55.

The tenth lens of the fish eye lens are the glass lens of refractive index 1.40-1.55, abbe number 70-80, focal length For 8mm, R1 curvature radius is 3-6, R2 facial plane.Described ten index of refraction in lens preferably 1.55, abbe number are preferably 75。

Detailed description of the invention

Fig. 1 is fish-eye optical system structure schematic diagram of the present invention.

Fig. 2 is first edition chromaticity difference diagram (in 0.43nm wave band maximum value 10 or more).

Fig. 3 is second edition chromaticity difference diagram (in 0.43nm wave band maximum value 3 or so).

Fig. 4 is 230 ° of MTF curve figures.

Fig. 5 is 230 ° of DIST curve graphs.

Fig. 6 is 230 ° of acutance figures.

Specific embodiment:

As shown in Fig. 1-6, it is illustrated to make the objectives, technical solutions, and advantages of the present invention clearer.In conjunction with specific Embodiment, the present invention is described in detail.During this, descriptions of well-known structures and technologies are omitted, with to avoid To unnecessarily obscuring idea of the invention.For these descriptions, only it is exemplary.It is not to limit the scope of the invention.

Every lens use different refraction materials, so that light changes, so that resolving power reaches best；Specifically It is as follows:

First higher glass material of the lower abbe number of 1 refractive index of lens；(ranges of indices of refraction 1.5-1.6 is preferred 1.55 left and right；Abbe number range 70-75 preferably 72 or so) focal length: f=-15mm radius of curvature: the face R1 15-18；The face R2 8- 10。

Second lower glass material of the higher abbe number of 2 refractive index of lens；(ranges of indices of refraction 1.75-1.90 is preferred 1.80 left and right；Abbe number range 40-50 preferably 45 or so) focal length: f=-8mm radius of curvature: the face R1 15-20；The face R2 3-6.

The lower glass material of the third piece lens higher abbe number of 3 refractive index；(ranges of indices of refraction 1.8-1.85 is preferred 1.82 left and right；Abbe number range 30-35 preferably 34 or so) focal length: f=-7mm radius of curvature: the face R1-10~-12；The face R2 4- 10。

The 4th higher glass material of the lower abbe number of 4 refractive index of lens；(ranges of indices of refraction 1.78-1.95 is preferred 1.86 left and right；Abbe number range 20-30 preferably 25 or so) focal length: f=4mm radius of curvature: the face R1 3-6；The face R2-10~- 15。

Four or five lens are cemented lens focal length: f=12mm.

The lower glass material of the higher abbe number of 6 refractive index of six-element lens；(ranges of indices of refraction 1.78-1.90 is preferred 1.83 left

It is right；Abbe number range 20-30 preferably 26 or so) focal length: f=8mm radius of curvature: the face R1 4-6；The face R2-6~- 10。

The 7th lower glass material of the higher abbe number of 7 refractive index of lens；(ranges of indices of refraction 1.78-1.95 is preferred 1.80 left and right；Abbe number range 20-30 preferably 25 or so) focal length: f=-8mm radius of curvature: the face R1 3-6；The face R2-10~- 15。

Six or seven lens are cemented lens focal length: f=15mm.

The 8th lower glass material of the higher abbe number of 8 refractive index of lens；(ranges of indices of refraction 1.78-1.95 is preferred 1.88 left and right；Abbe number range 20-30 preferably 25 or so) focal length: f=-10mm radius of curvature: the face R1 15-20；The face R2 3-6.

The moderate glass material of the 9th moderate abbe number of 9 refractive index of lens；(ranges of indices of refraction 1.70-1.80 is preferred 1.75 left and right；Abbe number range 50-60 preferably 55 or so) focal length: f=7mm radius of curvature: the face R1 15-20；The face R2-10~- 15。

The tenth higher glass material of the lower abbe number of 10 refractive index of lens；(ranges of indices of refraction 1.40-1.55 is preferred 1.55 left and right；Abbe number range 70-80 preferably 75 or so) focal length: f=8mm radius of curvature: the face R1 3-6；R2 facial plane.

100 be imaging plane, i.e. photosensitive element.

The comparison of Fig. 2 and Fig. 3, it is evident that the latter's color difference has larger improvement.

Amendment is made for purple boundary, optimizes optical texture, is collocated with each other by the dispersion from high to low of ten lens, Purple boundary after imaging is modified, so that smaller than the imaging purple boundary range of first edition product.

Claims

1. A fisheye lens, characterized in that the 1st to 10th lens structures are arranged in sequence from the object side to the image side, including two cemented lens groups; The cemented lens group is cemented by the fourth and fifth lenses, and the second cemented lens group is cemented by the sixth and seventh lenses;

The first lens is glass material; refractive index range is 1.5-1.6; dispersion coefficient range is 70-75; focal length: f=-15mm; curvature radius: R1 surface 15-18mm; R2 surface 8-10mm;

The second lens is made of glass material; the refractive index range is 1.75-1.90; the dispersion coefficient range is 40-50; focal length: f=-8mm; curvature radius: R1 surface 15-20mm; R2 surface 3-6mm;

The third lens is glass material; the refractive index range is 1.8-1.85; the dispersion coefficient range is 30-35; focal length: f=-7mm;

The fourth lens is made of glass material; the refractive index range is 1.78-1.95; the dispersion coefficient range is 20-30; focal length: f=4mm;

The fifth lens is a glass lens with a refractive index of 1.78-1.95, its dispersion coefficient is 20-30, and the focal length is 4mm; the radius of curvature of the R1 surface is 3-6mm, and the radius of curvature of the R2 surface is -10 to -15mm;

The fourth and fifth lenses are combined into the first cemented lens group, effective focal length: f=12mm;

The sixth lens is glass material; the refractive index range is 1.78-1.90; the dispersion coefficient range is 20-30; focal length: f=8mm;

The seventh lens is glass material; the refractive index range is 1.78-1.95; the dispersion coefficient range is 20-30; focal length: f=-8mm;

The sixth and seventh lenses are combined into the second cemented lens group, effective focal length: f=15mm;

The eighth lens is glass material; refractive index range is 1.78-1.95; dispersion coefficient range is 20-30; focal length: f=-10mm; curvature radius: R1 surface 15-20mm; R2 surface 3-6mm;

The ninth lens is made of glass material; the refractive index range is 1.70-1.80; the dispersion coefficient range is 50-60; focal length: f=7mm;

The tenth lens is made of glass material; refractive index range is 1.40-1.55; dispersion coefficient range is 70-80; focal length: f=8mm; curvature radius: R1 surface 3-6mm; R2 surface is a plane;

The R1 surface is the lens object surface, and the R2 surface is the lens image surface.

2 . The fisheye lens according to claim 1 , wherein the sixth lens is a glass lens with a refractive index of 1.83, and its dispersion coefficient is 26. 3 .

3 . The fisheye lens according to claim 1 , wherein the seventh lens is a glass lens with a refractive index of 1.80, and its dispersion coefficient is 25. 4 .

4 . The fisheye lens according to claim 1 , wherein the eighth lens is a glass lens with a refractive index of 1.88, and the dispersion coefficient thereof is 25. 5 .

5 . The fisheye lens of claim 1 , wherein the fourth lens is a glass lens with a refractive index of 1.86, and the dispersion coefficient thereof is 25. 6 .

6 . The fisheye lens according to claim 1 , wherein the fifth lens is a glass lens with a refractive index of 1.90, and the dispersion coefficient thereof is 25. 7 .

7 . The fisheye lens according to claim 1 , wherein the first lens is a glass lens with a refractive index of 1.55, and the dispersion coefficient thereof is 72. 8 .

8 . The fisheye lens according to claim 7 , wherein the second lens is a glass lens with a refractive index of 1.80, and its dispersion coefficient is 45. 9 .

9 . The fisheye lens of claim 8 , wherein the third lens is a glass lens with a refractive index of 1.82, and the dispersion coefficient thereof is 34. 10 .

10 . The fisheye lens of claim 9 , wherein the ninth lens is a glass lens with a refractive index of 1.75, and its dispersion coefficient is 55. 11 .

11 . The fisheye lens of claim 10 , wherein the tenth lens is a glass lens with a refractive index of 1.55 and a dispersion coefficient of 75. 12 .