CN108594405A

CN108594405A - It is a kind of to roll over the mixing wide-angle lens that spreads out

Info

Publication number: CN108594405A
Application number: CN201810530633.1A
Authority: CN
Inventors: 李劲松; 侍鹏
Original assignee: China Jiliang University
Current assignee: China Jiliang University
Priority date: 2018-05-29
Filing date: 2018-05-29
Publication date: 2018-09-28

Abstract

The mixing wide-angle lens that spreads out is rolled over the present invention relates to a kind of, includes the first lens, the second lens, the third lens, the 4th lens, diaphragm, the 5th lens, the 6th lens and the 7th lens successively from the object side to the image side；First lens are the negative meniscus lens that two sides is all even aspheric surface；Second lens are the biconcave lens that two sides is all even aspheric surface；The front surface of the third lens is spherical surface, and rear surface is binary diffraction face；4th lens are biconvex spherical lens；5th lens are concave-concave spherical lens；6th lens are biconvex spherical lens；7th lens are negative curved month type spherical lens；This uses folding and spreads out hybrid mode, and size is small, light-weight, and optics overall length is less than 18mm, has reached the imaging effect of big visual field, low distortion, low aberration, has had higher image quality.

Description

It is a kind of to roll over the mixing wide-angle lens that spreads out

Technical field

The present invention relates to a kind of optical lens more particularly to it is a kind of folding spread out mixing wide-angle lens.

Background technology

With the raising that market requires mobile phone image quality, for the design requirement of every optical parameter of mobile lens It is constantly updating, the design methods of mobile phone camera lens seems ever more important.

Mobile lens currently on the market mostly use refraction type structure, and eyeglass is more, and size is big, complicated, heavier-weight, And it also controls not to be fine in terms of aberration and thermal characteristics.

Invention content

The purpose of the present invention is to provide a kind of size is small, eyeglass is few, low aberration, and the folding with high imaging quality spreads out mixing Wide-angle lens.

To achieve the object of the present invention, technical solution provided by the invention is：

It is a kind of folding spread out mixing wide-angle lens, from the object side to the image side successively include the first lens, the second lens, the third lens, 4th lens, diaphragm, the 5th lens, the 6th lens and the 7th lens；First lens are that two sides is all the negative of even aspheric surface Meniscus lens；Second lens are the biconcave lens that two sides is all even aspheric surface；The front surface of the third lens is spherical surface, rear table Face is binary diffraction face；4th lens are biconvex spherical lens；5th lens are concave-concave spherical lens；6th lens are biconvex ball Face lens；7th lens are negative curved month type spherical lens.

The refractive index of first lens is 1.72, dispersion 38.0.

The refractive index of second lens is 1.57, dispersion 56.0.

The refractive index of the third lens is 1.52, dispersion 64.2.

The refractive index of 4th lens is 1.74, dispersion 44.9.

The refractive index of 5th lens is 1.74, dispersion 27.7.

The refractive index of 6th lens is 1.62, dispersion 58.1.

The refractive index of 7th lens is 1.70, dispersion 56.1.

The folding, which spreads out, mixes wide-angle lens, meets relational expression：15mm≤TTL≤20mm, wherein TTL are that the folding spreads out The object space side outermost point of wide-angle lens is mixed to the distance of imaging surface.

The folding, which spreads out, mixes wide-angle lens, meets relational expression：FOV >=64 °, wherein FOV are spread out for the folding mixes wide-angle The maximum field of view angle of camera lens.

The folding, which spreads out, mixes wide-angle lens, meets relational expression：D≤4%, wherein D spread out for the folding mixes wide-angle lens Distortion.

The folding, which spreads out, mixes wide-angle lens, meets relational expression：C≤4 μm, wherein C are spread out for the folding mixes wide-angle lens Chromatic longitudiinal aberration.

Compared with prior art, the present invention has the advantages that：Spread out hybrid lens combination side present invention employs folding Formula, has effectively corrected aberration, greatly reduces the size of camera lens, improves image quality, and still have larger visual field Angle is adapted to requirement of the mobile lens to size and image quality.

Description of the drawings

Fig. 1 is the structural diagram of the present invention.

Fig. 2 is the curvature of field and distortion schematic diagram of the present invention.

Fig. 3 is the MTF curve figure of the present invention.

Fig. 4 is the point range figure of the present invention.

Fig. 5 is the chromatic longitudiinal aberration figure of the present invention.

Specific implementation mode

The mixing wide-angle lens as shown in Figure 1, a kind of folding spreads out, is followed successively by the first lens 1 from the object side to the image side, the second lens 2, The third lens 3, the 4th lens 4, diaphragm 5, the 5th lens 6, the 6th lens 7, the 7th lens 8 and image planes 9.First lens 1 for two sides be all even aspheric surface negative meniscus lens, second lens 2 be two sides be all even aspheric surface concave-concave it is saturating The front surface of mirror, the third lens 3 is spherical surface, and rear surface is binary diffraction face, and the 4th lens 4 are that biconvex spherical surface is saturating Mirror, the 5th lens 6 are concave-concave spherical lens, and the 6th lens 7 are biconvex spherical lens, and the 7th lens 8 are negative Curved month type spherical lens.

In the present invention, the first lens 1, the second lens 2 are all the non-spherical lens that two sides is all even aspheric surface, and lens are bent Face can be very good to correct aberration using aspherical, reach higher image quality requirement.

In the present invention, the third lens 3 are that front surface is spherical surface, and rear surface is binary diffraction face, and folding is used in lens group Spread out the mode of mixing, it, can be with by the setting to binary diffraction face position phase parameter according to the special dispersion characteristics of binary diffraction face The aberration that correction spherical system is brought well, and it is greatly reduced the lateral dimension of camera lens.

F=8.47mm in the present invention, FOV=64 °, FNO=2.37, TTL=17.32mm.

F is the whole focal length value of camera lens, and FNO is f-number, and FOV is full filed angle, and TTL is optical lens overall length.

Optical system parameter table of the present invention is shown in Table 1

Table 1

It is aspherical that the minute surface of " * " number is beaten in table 1, and related coefficient is shown in Table 2；

First lens 1, the second lens 2 are aspherical meets following equation：

In formula：Z be it is aspherical along optical axis direction when being highly the positions h, apart from aspheric vertex of surface apart from rise.

C=1/r, r indicate that the radius of curvature of aspheric vertex of surface, k are circular cone coefficient, and A, B, C, D, E are high order aspheric surface system Number, E represent scientific notation.

Asphericity coefficient k, A, B, C, D, E：

Table 2

Face serial number	k	A	B	C	D	E
							1	0.0081	-6.59E-05	2.39E-06	-8.29E-09	1.11E-09	8.7E-11
2	0.203	-2.25E-06	4.13E-06	1.74E-07	-2.1E-08	-4.9E-10
							3	164.748	0	0	0	0	0
4	0.0056	0	0	0	0	0

The minute surface that " # " number is beaten in table 1 is binary diffraction face, and related coefficient is shown in Table 3；

The position phase parameter of the diffraction surfaces is determined by following equation：

In formula：M is diffraction progression, and N is diffraction surfaces multinomial coefficient, and Ai is the polynomial coefficient of diffraction surfaces, and ρ is diffraction surfaces Aperture.

Diffraction face data is as follows：

Table 3

M	N	A1	A2	A3	A4
						1	4	-0.071	1.06E-03	-2.83E-05	5.38E-06

From Fig. 1-5 it can be seen that this optical system have good optical property, realize big field angle, it is low distortion, it is low The characteristic of aberration.

Claims

The mixing wide-angle lens 1. a kind of folding spreads out, it is characterised in that：The camera lens includes the first lens, the successively from the object side to the image side Two lens, the third lens, the 4th lens, diaphragm, the 5th lens, the 6th lens and the 7th lens；First lens be two sides all It is the negative meniscus lens of even aspheric surface；Second lens are the biconcave lens that two sides is all even aspheric surface；The third lens Front surface is spherical surface, and rear surface is binary diffraction face；4th lens are biconvex spherical lens；5th lens are that concave-concave spherical surface is saturating Mirror；6th lens are biconvex spherical lens；7th lens are negative curved month type spherical lens.
The mixing wide-angle lens 2. folding as described in claim 1 spreads out, it is characterised in that：Meet conditional：15mm≤TTL≤ 20mm, wherein TTL are distance of the object space side outermost point for rolling over the mixing wide-angle lens that spreads out to image planes.
The mixing wide-angle lens 3. folding as described in claim 1 spreads out, it is characterised in that：Meet conditional：FOV >=64 °, wherein FOV is the maximum field of view angle for rolling over the mixing wide-angle lens that spreads out.
The mixing wide-angle lens 4. folding as described in claim 1 spreads out, it is characterised in that：The refractive index of first lens is 1.72, dispersion 38.0；The refractive index of second lens is 1.57, dispersion 56.0；The refractive index of the third lens is 1.52, dispersion 64.2；The refractive index of 4th lens is 1.74, dispersion 44.9；The refractive index of 5th lens is 1.74, dispersion 27.7；The refractive index of 6th lens is 1.62, dispersion 58.1；The refractive index of 7th lens is 1.70, dispersion 56.1.
The mixing wide-angle lens 5. folding as described in claim 1 spreads out, it is characterised in that：Meet conditional：D≤4%, wherein D are institute State the distortion for rolling over the mixing wide-angle lens that spreads out.
The mixing wide-angle lens 6. folding as described in claim 1 spreads out, it is characterised in that：Meet conditional：C≤4 μm, wherein C are The folding, which spreads out, mixes the chromatic longitudiinal aberration of wide-angle lens.