CN101738707B - Four-piece photographic optical lens group - Google Patents

Abstract

The invention discloses a four-piece photographic optical lens group, comprising: a first lens element with positive refractive power having an Abbe number V1, 50< V1< 60; a second lens element with negative refractive power having a concave front surface and a convex rear surface; a third lens element, which has a convex front surface and a concave rear surface, and at least one surface of which is aspheric; a fourth lens element, at least one surface of which is aspheric; an aperture stop is disposed in front of the second lens.

Description

Four-piece photographic optical lens group

technical field

The invention relates to an optical mirror group, in particular to a four-piece photographic optical mirror group applied to a miniaturized photographic lens.

Background technique

In recent years, with the rise of mobile phone cameras, the demand for miniaturized photographic lenses has increased day by day, and the photosensitive element of general photographic lenses is nothing more than a photosensitive coupling device (Charge Coupled Device, CCD) or a complementary metal oxide semiconductor (Complementary Metal) -Oxide Semiconductor, CMOS) two types, due to the advancement of semiconductor manufacturing technology, the pixel area of the photosensitive element is reduced, and the miniaturized photographic lens is gradually developing into the high-pixel field. Therefore, the requirements for imaging quality are also increasing.

Common mobile phone lenses mostly use a three-piece lens group. The lens group consists of a first lens with positive refractive power, a second lens with negative refractive power, and a third lens with positive refractive power from the object side to the image side. Three lenses, as shown in US patent specification US7145736B2 (announced on December 5, 2006).

As the pixel area of the photosensitive element gradually shrinks, the system's requirements for imaging quality increase, and the common three-piece lens group will not be able to meet the use of higher-end photographic lens modules.

U.S. patent specification US7365920B2 (announced on April 29, 2008) discloses a four-piece lens group, but wherein the first lens and the second lens are bonded to each other with two spherical mirrors to form a Doublet to eliminate chromatic aberration, but This method has its disadvantages. First, too many configurations of spherical mirrors make the degree of freedom of the system insufficient, making it difficult to shorten the overall length of the optical system. Second, the glass lens bonding process is not easy, resulting in difficulties in manufacturing.

Contents of the invention

The technical problem to be solved by the present invention is: in order to improve the imaging quality of the optical system and effectively shorten the lens size, a photographic optical mirror group consisting of four lenses will be provided.

In order to solve the above-mentioned technical problems, the four-piece photographic optical lens group of the present invention includes between the object side and the image side:

a first lens with positive refractive power;

A second lens with negative refractive power, the front surface of which is concave and the rear surface is convex, and the second lens is arranged behind the first lens;

A third lens with a convex front surface and a concave rear surface, the third lens is arranged behind the second lens, and at least one surface of the third lens is aspherical;

A fourth lens, at least one surface of which is set as an aspheric surface, the fourth lens is arranged behind the third lens; and

An aperture, placed in front of the second lens.

In the four-piece photographic optical lens group of the present invention, the refractive power of the four-piece photographic optical lens group is mainly provided by the first lens with positive refractive power, and the function of the second lens with negative refractive power is mainly to correct chromatic aberration, and the second lens with negative refractive power is mainly used to correct chromatic aberration. The third lens and the fourth lens function as a correction lens, and their function is to balance and correct various aberrations generated by the system.

With the strong positive refractive power provided by the first lens, and the aperture being placed close to the object side of the four-piece photographic optical lens group, the total length of the four-piece photographic optical lens group can be effectively shortened. In addition, the above configuration can make The exit pupil (Exit Pupil) of the four-piece photographic optical lens group is far away from the imaging surface, so the light will be incident on the photosensitive element in a manner close to vertical incidence, which is the telecentric characteristic of the imaging side, and the telecentric characteristic The photosensitivity of the current solid-state electronic photosensitive element is extremely important, which will increase the photosensitive sensitivity of the electronic photosensitive element and reduce the possibility of vignetting caused by the four-piece photographic optical mirror group. In addition, setting inflection points on the third lens and the fourth lens can effectively suppress the angle at which the light from the off-axis field of view is incident on the photosensitive element, and make the peripheral image plane flatter.

In addition, in the wide-angle optical system, it is especially necessary to correct the distortion (Distortion) and the chromatic aberration of magnification (Chromatic Aberration of Magnification). The method is to place the aperture at the balance of the optical refractive power of the system.

If the present invention places the aperture in front of the first lens, the telecentricity is emphasized, and the total optical length of the system can be shorter. If the aperture is placed between the first lens and the second lens, more emphasis will be placed on the characteristics of a wide field of view. At the same time, such an arrangement of the aperture position can effectively reduce the sensitivity of the system.

In the four-piece photographic optical lens group of the present invention, the front surface of the first lens is convex, and the rear surface can be convex or concave. When the rear surface of the first lens is convex, the system focuses on the correction of spherical aberration (Spherical Aberration). When the back surface of the first lens is concave, the system focuses on the correction of astigmatism. The second lens has a concave front surface and a convex back surface. The third lens has a convex front surface and a concave back surface. The fourth lens has a convex front surface and a concave back surface. The front surface of the lens is convex, and the rear surface is concave. The configuration of the above-mentioned mirror shape can effectively improve the imaging quality.

With the trend of miniaturization of camera phone lenses and the need for the system to cover a wide range of viewing angles, the focal length of the optical system becomes very short. In this case, the radius of curvature of the lens and the size of the lens become very small. Traditionally The method of glass grinding will make it difficult to manufacture the above-mentioned lenses. Therefore, using plastic materials on the lens and making the lens by injection molding can produce high-precision lenses at a relatively low cost; and set aspheric surfaces on the mirror surface , the aspherical surface can be easily made into a shape other than a spherical surface, and more control variables can be obtained to reduce aberrations, thereby reducing the number of lenses used.

In the four-piece photographic optical lens group of the present invention, the refractive index of the first lens is N1, and the refractive index of the third lens is N3, which will satisfy the following relational expression:

1.52 < N1 < 1.58;

1.52 < N3 < 1.58;

When N1 and N3 satisfy the above relationship, it is easy to find a suitable plastic material to match the four-piece photographic optical lens group.

In the four-piece photographic optical mirror group of the present invention, the focal length of the overall four-piece photographic optical mirror group is f, the focal length of the first lens is f1, and the focal length of the second lens is f2, which will satisfy the following relationship:

0.8 < f/f1 < 1.2;

-0.75 < f/f2 < -0.3;

When f/f1 is less than the lower limit, it will cause insufficient refractive power, making the total optical length too long, and it is difficult to suppress the angle of light incident on the photosensitive element; if f/f1 is greater than the upper limit, the height of the four-piece photographic optical lens group Order aberrations will be too large. When f/f2 is less than the lower limit, the total optical length will be too long; if f/f2 is greater than the upper limit, it will be difficult for the four-piece photographic optical lens group to correct chromatic aberration. Furthermore, it is ideal to make f/f1 and f/f2 satisfy the following relationship:

0.95 < f/f1 < 1.15;

-0.5 < f/f2 < -0.3.

In the four-piece photographic optical mirror group of the present invention, the focal length of the overall four-piece photographic optical mirror group is f, the focal length of the third lens is f3, and the focal length of the fourth lens is f4, which will satisfy the following relationship:

-0.2 < f/f3 < 0.2;

-0.2 < f/f4 < 0.2;

The functions of the third lens and the fourth lens are correction lenses, and their function is to balance and correct various aberrations produced by the four-piece photographic optical lens group.

In the four-piece photographic optical mirror group of the present invention, the mirror spacing between the third lens and the fourth lens is T34, and the focal length of the overall four-piece photographic optical mirror group is f, which will satisfy the following relationship:

T34/f > 0.015;

When T34/f satisfies the above relationship, it will be beneficial to correct the high-order aberration of the four-piece photographic optical lens group.

In the four-piece photographic optical lens group of the present invention, the dispersion coefficient of the first lens is V1, the dispersion coefficient of the second lens is V2, and the dispersion coefficient of the third lens is V3, which will satisfy the following relationship:

50 < V1 < 60;

V1-V2 > 15;

V3-V2 > 15;

When V1, V2 and V3 satisfy the above relationship, it will be beneficial to correct the chromatic aberration (Chromatic Aberration) of the four-piece photographic optical lens group, and improve the resolution of the four-piece photographic optical lens group; further, V2 can satisfy the following A relational expression would be ideal:

V2 < 26.8.

In the four-piece photographic optical lens group of the present invention, the radius of curvature of the front surface of the first lens is R1, and the radius of curvature of the rear surface of the first lens is R2, which will satisfy the following relationship:

0.2<R1/R2<0.5;

When R1/R2 is lower than the lower limit of the above relationship, the astigmatism produced by the four-piece photographic optical lens group will be difficult to correct; when R1/R2 is higher than the upper limit of the above relationship, the four-piece photography The spherical aberration (Spherical Aberration) produced by the optical lens group will be difficult to correct; further, it is more ideal to make R1 and R2 satisfy the following relationship:

0.3 < R1/R2 < 0.5.

In the four-piece photographic optical mirror group of the present invention, an electronic photosensitive element is additionally provided for subject imaging, and the optical total length of the four-piece photographic optical mirror group is TTL, and the maximum imaging height of the four-piece photographic optical mirror group is 1mgH , will satisfy the following relation:

TTL/ImgH<1.9;

The above relational expression can maintain the miniaturization characteristics of the four-piece photographic optical lens group.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the present invention will be described in further detail:

Fig. 1 is the schematic diagram of the optical system of the first embodiment of the present invention;

Fig. 2 is an aberration curve diagram of the first embodiment of the present invention;

Fig. 3 is a schematic diagram of the optical system of the second embodiment of the present invention;

Fig. 4 is an aberration curve diagram of the second embodiment of the present invention;

Fig. 5 is a schematic diagram of the optical system of the third embodiment of the present invention;

FIG. 6 is an aberration graph of the third embodiment of the present invention.

The reference signs in the figure are: 10—the first lens; 11—the front surface; 12—the rear surface;

20—second lens; 21—front surface; 22—rear surface;

30—the third lens; 31—the front surface; 32—the rear surface;

40—the fourth lens; 41—the front surface; 42—the rear surface;

50—aperture;

60—infrared filter;

70—imaging surface;

f—the focal length of the overall four-piece photographic optical lens group;

f1—the focal length of the first lens;

f2—the focal length of the second lens;

f3—the focal length of the third lens;

f4—the focal length of the fourth lens;

N1—the refractive index of the first lens;

N3—the refractive index of the third lens;

V1—the dispersion coefficient of the first lens;

V2—the dispersion coefficient of the second lens;

V3—the dispersion coefficient of the third lens;

T34—mirror spacing between the third lens and the fourth lens;

R1—the radius of curvature of the front surface of the first lens;

R2—the radius of curvature of the rear surface of the first lens;

TTL—the total optical length of the overall four-piece photographic optical lens group;

ImgH—the maximum imaging height of the overall four-piece photographic optical mirror group.

Detailed ways

Please refer to Figure 1 for the first embodiment of the present invention, please refer to Figure 2 for the aberration curve of the first embodiment, the first embodiment includes between the object side and the image side:

A first lens 10 with positive refractive power is made of plastic, and the front surface 11 of the first lens 10 is convex, and the rear surface 12 is concave. In addition, the front surface 11 and the rear surface 12 of the first lens 10 are both set Aspherical;

A second lens 20 with negative refractive power is made of plastic, and the front surface 21 of the second lens 20 is concave, and the rear surface 22 is convex. In addition, the front surface 21 and the rear surface 22 of the second lens 20 are both set Aspherical;

A third lens 30 with positive refractive power is made of plastic, and the front surface 31 of the third lens 30 is convex, and the rear surface 32 is concave. In addition, the front surface 31 and the rear surface 32 of the third lens 30 are both set Aspheric surface, and both the front surface 31 and the rear surface 32 of the third lens 30 are provided with inflection points;

A fourth lens 40 with negative refractive power is made of plastic, and the front surface 41 of the fourth lens 40 is convex, and the rear surface 42 is concave. In addition, the front surface 41 and the rear surface 42 of the fourth lens 40 are both set Aspherical surface, and both the front surface 41 and the rear surface 42 of the fourth lens 40 are provided with inflection points;

An aperture 50 is placed between the first lens 10 and the second lens 20;

An infrared filter (IR Filter) 60 is placed behind the fourth lens 40, which does not affect the focal length of the system;

An imaging surface 70 is placed behind the infrared filter 60 .

The equation of the above aspheric curve is expressed as follows:

$\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; sqrt</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Ai</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span>$

in:

X: The point on the aspheric surface whose distance from the optical axis is Y, and its distance from the tangent plane tangent to the vertex on the aspheric optical axis.

Y: the distance from the point on the aspheric curve to the optical axis;

k: cone coefficient;

Ai: i-th aspheric coefficient.

In the first embodiment, the focal length of the overall four-piece photographic optical lens group is f, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, and the focal length of the fourth lens is f4 , its relationship is:

f=3.30[mm];

f/f1=1.08;

f/f2 = -0.36;

f/f3=0.06;

f/f4=-0.02.

In the first embodiment, the refractive index of the first lens is N1=1.544.

In the first embodiment, the refractive index of the third lens is N3=1.530.

In the first embodiment, the Abbe Number of the first lens is V1, the Abbe Number of the second lens is V2, and the Abbe Number of the third lens is V3, and its relationship is:

V1=56.1;

V2=23.4;

V1-V2=32.7;

V3-V2=32.4.

In the first embodiment, the mirror spacing between the third lens and the fourth lens is T34, and the focal length of the overall four-piece photographic optical lens group is f, and its relationship is:

T34/f = 0.10.

In the first embodiment, the radius of curvature of the front surface of the first lens is R1, and the radius of curvature of the rear surface of the first lens is R2, and the relationship is as follows:

R1/R2=0.21.

In the first embodiment, the optical total length of the integral four-piece photographic optical mirror group is TTL, and the maximum imaging height of the integral four-piece photographic optical mirror group is ImgH, and its relational expression is:

TTL/ImgH = 1.72.

The detailed structural data of the first embodiment are shown in Table 1, and the aspheric data are shown in Table 2, where the units of the radius of curvature, thickness and focal length are mm, and HFOV is defined as half of the maximum viewing angle.

Table 1 Structural data of the first embodiment of the present invention

Table 2 The aspherical surface data of the first embodiment of the present invention

Please refer to FIG. 3 for the second embodiment of the present invention. Please refer to FIG. 4 for the aberration curve of the second embodiment. The second embodiment includes between the object side and the image side:

A first lens 10 with positive refractive power is made of plastic, and the front surface 11 of the first lens 10 is convex, and the rear surface 12 is concave. In addition, the front surface 11 and the rear surface 12 of the first lens 10 are both set Aspherical;

A second lens 20 with negative refractive power is made of plastic, and the front surface 21 of the second lens 20 is concave, and the rear surface 22 is convex. In addition, the front surface 21 and the rear surface 22 of the second lens 20 are both set Aspherical;

A third lens 30 with positive refractive power is made of plastic, and the front surface 31 of the third lens 30 is convex, and the rear surface 32 is concave. In addition, the front surface 31 and the rear surface 32 of the third lens 30 are both set Aspheric surface, and both the front surface 31 and the rear surface 32 of the third lens 30 are provided with inflection points;

A fourth lens 40 with positive refractive power is made of plastic, and the front surface 41 of the fourth lens 40 is convex, and the rear surface 42 is concave. In addition, the front surface 41 and the rear surface 42 of the fourth lens 40 are both set Aspherical surface, and both the front surface 41 and the rear surface 42 of the fourth lens 40 are provided with inflection points;

An aperture 50 is placed between the first lens 10 and the second lens 20;

An infrared filter (IR Filter) 60 is placed behind the fourth lens 40, which does not affect the focal length of the system;

An imaging surface 70 is placed behind the infrared filter 60 .

The expression of the aspheric curve equation of the second embodiment is the same as that of the first embodiment.

In the second embodiment, the focal length of the overall four-piece photographic optical lens group is f, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, and the focal length of the fourth lens is f4 , its relationship is:

f = 3.22 [mm];

f/f1=1.02;

f/f2 = -0.40;

f/f3=0.13;

f/f4=0.08.

In the second embodiment, the refractive index of the first lens is N1=1.544.

In the second embodiment, the refractive index of the third lens is N3=1.544.

In the second embodiment, the dispersion coefficient of the first lens is V1, the dispersion coefficient of the second lens is V2, and the dispersion coefficient of the third lens is V3, and their relational expressions are:

V1=56.1;

V2=23.4;

V1-V2=32.7;

V3-V2=32.7.

In the second embodiment, the mirror distance between the third lens and the fourth lens is T34, and the focal length of the overall four-piece photographic optical lens group is f, and its relationship is:

T34/f = 0.08.

In the second embodiment, the radius of curvature of the front surface of the first lens is R1, and the radius of curvature of the rear surface of the first lens is R2, and the relationship is as follows:

R1/R2=0.32.

In the second embodiment, the optical total length of the integral four-piece photographic optical mirror group is TTL, and the maximum imaging height of the integral four-piece photographic optical mirror group is ImgH, and its relational expression is:

TTL/ImgH = 1.73.

The detailed structure data of the second embodiment is shown in Table 3, and its aspheric surface data is shown in Table 4, where the units of the radius of curvature, thickness and focal length are mm, and HFOV is defined as half of the maximum viewing angle.

Table 3 Structural data of the second embodiment of the present invention

Table 4 The aspheric surface data of the second embodiment of the present invention

Please refer to FIG. 5 for the third embodiment of the present invention. Please refer to FIG. 6 for the aberration curve of the third embodiment. The third embodiment includes between the object side and the image side:

A first lens 10 with positive refractive power is made of plastic, and the front surface 11 of the first lens 10 is convex, and the rear surface 12 is concave. In addition, the front surface 11 and the rear surface 12 of the first lens 10 are both set Aspherical;

A second lens 20 with negative refractive power is made of plastic, and the front surface 21 of the second lens 20 is concave, and the rear surface 22 is convex. In addition, the front surface 21 and the rear surface 22 of the second lens 20 are both set Aspherical;

A third lens 30 with negative refractive power is made of plastic, and the front surface 31 of the third lens 30 is convex, and the rear surface 32 is concave. In addition, the front surface 31 and the rear surface 32 of the third lens 30 are both set Aspheric surface, and both the front surface 31 and the rear surface 32 of the third lens 30 are provided with inflection points;

A fourth lens 40 with positive refractive power is made of plastic, and the front surface 41 of the fourth lens 40 is convex, and the rear surface 42 is concave. In addition, the front surface 41 and the rear surface 42 of the fourth lens 40 are both set Aspherical surface, and both the front surface 41 and the rear surface 42 of the fourth lens 40 are provided with inflection points;

An aperture 50 is placed between the first lens 10 and the second lens 20;

An infrared filter (IR Filter) 60 is placed behind the fourth lens 40, which does not affect the focal length of the system;

An imaging surface 70 is placed behind the infrared filter 60 .

The expression of the aspheric curve equation of the third embodiment is the same as that of the first embodiment.

In the third embodiment, the focal length of the overall four-piece photographic optical lens group is f, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, and the focal length of the fourth lens is f4 , its relationship is:

f=3.31[mm];

f/f1=1.14;

f/f2 = -0.40;

f/f3=-0.06;

f/f4=0.10.

In the third embodiment, the refractive index of the first lens is N1=1.544.

In the third embodiment, the refractive index of the third lens is N3=1.544.

In the third embodiment, the dispersion coefficient of the first lens is V1, the dispersion coefficient of the second lens is V2, and the dispersion coefficient of the third lens is V3, and their relational expressions are:

V1=56.1;

V2=23.4;

V1-V2=32.7;

V3-V2=32.7.

In the third embodiment, the mirror distance between the third lens and the fourth lens is T34, and the focal length of the overall four-piece photographic optical lens group is f, and its relational expression is:

T34/f = 0.08.

In the third embodiment, the radius of curvature of the front surface of the first lens is R1, and the radius of curvature of the rear surface of the first lens is R2, and the relationship is as follows:

R1/R2=0.22.

In the third embodiment, the optical total length of the integral four-piece photographic optical mirror group is TTL, and the maximum imaging height of the integral four-piece photographic optical mirror group is ImgH, and its relational expression is:

TTL/ImgH = 1.73.

The detailed structure data of the third embodiment is shown in Table 5, and the aspheric surface data is shown in Table 6, where the unit of the radius of curvature, thickness and focal length is mm, and HFOV is defined as half of the maximum viewing angle.

Table 5 Structural data of the third embodiment of the present invention

Table 6 The aspheric surface data of the third embodiment of the present invention

It is stated in advance here that Table 1 to Table 6 show the different numerical change tables of the embodiments of the four-piece photographic optical lens group, but the numerical changes of the various embodiments of the present invention are all experimental results, even if different numerical values are used, the same structure The products should still belong to the protection category of the present invention, and table 7 is the numerical data corresponding to the relevant equations of the present invention for each embodiment.

first embodiment second embodiment third embodiment f 3.30 3.22 3.31 Fno 2.45 2.45 2.45 HFOV 34.0 34.5 34.0 N1 1.544 1.544 1.544 N3 1.530 1.544 1.544 V1 56.1 56.1 56.1 V2 23.4 23.4 23.4 V1-V2 32.7 32.7 32.7 V3-V2 32.4 32.7 32.7 f/f1 1.08 1.02 1.14 f/f2 -0.36 -0.40 -0.40 f/f3 0.06 0.13 -0.06 f/f4 -0.02 0.08 0.10 T34/f 0.10 0.08 0.08 R1/R2 0.21 0.32 0.22 TTL/ImgH 1.72 1.73 1.73

Table 7 Numerical data corresponding to relevant equations in various embodiments of the present invention

To sum up, the present invention is a four-piece photographic optical lens group, whereby the lens structure, arrangement and lens configuration can effectively reduce the size of the lens group, and at the same time obtain higher resolution.

Therefore, the "practicability" of the present invention should be beyond doubt. In addition, the characteristic technology disclosed in the embodiment of this case has not been seen in various publications before the application, nor has it been publicly used. It not only has the above-mentioned effects The fact of improvement has additional effects that cannot be ignored. Therefore, the "novelty" and "creativity" of the present invention have already complied with patent laws and regulations. Therefore, an application for a patent for invention is filed in accordance with the law, and I pray for the review and approval of the patent as soon as possible. , I really feel that virtue is convenient.

Claims (12)

1. four-lens type photography optical lens group is characterized in that: comprise in the thing side and between as side:

First lens of the positive refracting power of one tool, the first lens abbe number is V1, and 50＜V1＜60;

Second lens of the negative refracting power of one tool, its front surface is a concave surface, and the surface, back is a convex surface, and these second lens are arranged at after first lens;

One the 3rd lens, its front surface are convex surface, and the surface, back is a concave surface, and the 3rd lens are arranged at after second lens, and at least one surface of the 3rd lens is made as aspheric surface;

One the 4th lens are plastic cement material, and its front surface is a convex surface, and surface, back is a concave surface, and front surface and afterwards the surface be all aspheric surface, the 4th lens are arranged at after the 3rd lens;

One aperture places between first lens and second lens;

In the said four-lens type photography optical lens group; Number with refracting power lens is merely four, and the focal length of whole four-lens type photography optical lens group is f, and the focal length of the 3rd lens is f3; The focal length of the 4th lens is f4; The front surface radius-of-curvature of first lens is R1, and the back surface curvature radius of first lens is R2, and its relational expression is:

-0.2＜f/f3＜0.2；

-0.2＜f/f4＜0.2；

0.2＜R1/R2＜0.5。

2. four-lens type photography optical lens group is characterized in that: comprise in the thing side and between as side:

First lens of the positive refracting power of one tool, the first lens abbe number is V1, and 50＜V1＜60;

Second lens of the negative refracting power of one tool, its front surface is a concave surface, and the surface, back is a convex surface, and these second lens are arranged at after first lens;

One the 3rd lens, its front surface are convex surface, and the surface, back is a concave surface, and the 3rd lens are arranged at after second lens, and at least one surface of the 3rd lens is made as aspheric surface;

One the 4th lens are plastic cement material, and its front surface is a convex surface, and surface, back is a concave surface, and front surface and afterwards the surface be all aspheric surface, the 4th lens are arranged at after the 3rd lens;

One aperture places between first lens and second lens;

In the said four-lens type photography optical lens group; Number with refracting power lens is merely four, and the focal length of whole four-lens type photography optical lens group is f, and the focal length of first lens is f1; The focal length of second lens is f2; The front surface radius-of-curvature of first lens is R1, and the back surface curvature radius of first lens is R2, and its relational expression is:

0.8＜f/f1＜1.2；

-0.75＜f/f2＜-0.3；

0.2＜R1/R2＜0.5。

3. four-lens type photography optical lens group according to claim 2 is characterized in that: wherein, the focal length of whole four-lens type photography optical lens group is f, and the focal length of first lens is f1, and the focal length of second lens is f2, and its relational expression is:

0.95＜f/f1＜1.15。

-0.5＜f/f2＜-0.3。

4. four-lens type photography optical lens group is characterized in that: comprise in the thing side and between as side:

First lens of the positive refracting power of one tool, the first lens abbe number is V1, and the front surface radius-of-curvature of 50＜V1＜60, the first lens is R1, and the back surface curvature radius of first lens is R2, and its relational expression is: 0.3＜R1/R2＜0.5;

Second lens of the negative refracting power of one tool, its front surface is a concave surface, and the surface, back is a convex surface, and these second lens are arranged at after first lens;

One the 3rd lens, its front surface are convex surface, and the surface, back is a concave surface, and the 3rd lens are arranged at after second lens, and at least one surface of the 3rd lens is made as aspheric surface;

One the 4th lens, its at least one surface is made as aspheric surface, and the 4th lens are arranged at after the 3rd lens;

One aperture places between first lens and second lens;

In the said four-lens type photography optical lens group, the number with refracting power lens is merely four.

5. four-lens type photography optical lens group is characterized in that: comprise in the thing side and between as side:

First lens of the positive refracting power of one tool are plastic cement material, and its front surface is a convex surface, and surface, back is a concave surface, and its front surface and afterwards the surface be all aspheric surface, the first lens abbe number is V1, and 50＜V1＜60; The front surface radius-of-curvature of first lens is R1, and the back surface curvature radius of first lens is R2, and its relational expression is: 0.3＜R1/R2＜0.5;

Second lens of the negative refracting power of one tool are plastic cement material, and its front surface is a concave surface, and surface, back is a convex surface, and its front surface and back surface be all aspheric surface, and these second lens are arranged at after first lens;

The 3rd lens of the positive refracting power of one tool are plastic cement material, and its front surface is a convex surface, and surface, back is a concave surface, and its front surface and afterwards the surface be all aspheric surface, the 3rd lens are arranged at after second lens;

One the 4th lens are plastic cement material, and its front surface is a convex surface, and surface, back is a concave surface, and front surface and afterwards the surface be all aspheric surface, the 4th lens are arranged at after the 3rd lens;

One aperture places between first lens and second lens;

In the said four-lens type photography optical lens group, the number with refracting power lens is merely four.

6. four-lens type photography optical lens group is characterized in that: comprise in the thing side and between as side:

First lens of the positive refracting power of one tool;

Second lens of the negative refracting power of one tool, these second lens are arranged at after first lens;

The 3rd lens of the negative refracting power of one tool, its front surface side's convex surface, the surface, back is a concave surface, the 3rd lens are arranged at after second lens and at least one surface of the 3rd lens is made as aspheric surface;

The 4th lens of the positive refracting power of one tool, its front surface are convex surface, and the surface, back is a concave surface, and the 4th lens are arranged at after the 3rd lens and at least one surface of the 4th lens is made as aspheric surface; And

One aperture places between first lens and second lens;

In the said four-lens type photography optical lens group, the number with refracting power lens is merely four, and the front surface radius-of-curvature of first lens is R1, and the back surface curvature radius of first lens is R2, and its relational expression is:

0.2＜R1/R2＜0.5。

7. four-lens type photography optical lens group according to claim 6 is characterized in that: wherein, second lens are plastic cement material, and its front surface is a concave surface, and surface, back is a convex surface, and front surface and afterwards the surface be all aspheric surface; The 3rd lens are plastic cement material, and front surface and the back surface be all aspheric surface; The 4th lens are plastic cement material, and front surface and the back surface be all aspheric surface.

8. four-lens type photography optical lens group according to claim 7 is characterized in that: wherein, first lens are plastic cement material, and its front surface is a convex surface, and surface, back is a concave surface, and front surface and afterwards the surface be all aspheric surface.

9. four-lens type photography optical lens group according to claim 6; It is characterized in that: wherein; The four-lens type photography optical lens group is established a sense electronics optical element in addition and is supplied the object imaging; The optics length overall of four-lens type photography optical lens group is TTL, and the maximum imaging of four-lens type photography optical lens group highly is ImgH, and its relational expression is:

TTL/ImgH＜1.9。

10. four-lens type photography optical lens group according to claim 6 is characterized in that: wherein, the refractive index of first lens is N1, and the abbe number of first lens is V1, and the abbe number of second lens is V2, and the abbe number of the 3rd lens is V3, and its relational expression is:

1.52＜N1＜1.58；

V1-V2＞15；

V3-V2＞15；

50＜V1＜60。

11. four-lens type photography optical lens group according to claim 10 is characterized in that: wherein, the focal length of whole four-lens type photography optical lens group is f, and the focal length of the 3rd lens is f3, and the focal length of the 4th lens is f4, and its relational expression is:

-0.2＜f/f3＜0；

0＜f/f4＜0.2。

12. four-lens type photography optical lens group according to claim 6 is characterized in that: wherein, the front surface radius-of-curvature of first lens is R1, and the back surface curvature radius of first lens is R2, and its relational expression is:

0.3＜R1/R2＜0.5。

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