CN101833160B - Camera optical lens group - Google Patents

Abstract

The invention provides an image pickup optical lens assembly, in order from an object side to an image side comprising: a first lens element with positive refractive power; a second lens element with negative refractive power having a concave front surface and a convex rear surface; a third lens element with negative refractive power having a concave front surface and a concave rear surface and having an inflection point; wherein the front surface and the rear surface of the second lens and the third lens are both provided with aspheric surfaces. The first lens can be a biconvex lens or a convex-concave crescent lens; when the first lens element is a biconvex lens element, the refractive power of the first lens element is increased, so that the total optical length of the system is shortened; when the first lens is a convex-concave crescent lens, the Astigmatism of the system is favorably corrected . The invention effectively corrects the aberration of the optical system through the configuration, improves the imaging quality and has the characteristic of thinning.

Description

Camera optical lens group

technical field

The present invention relates to a photographic optical lens group; in particular, to a thinned photographic optical lens group applied to a mobile phone camera.

Background technique

The existing thin mobile phone lens mainly adopts two-piece lens, such as that provided by US Patent No. 7,436,604. However, due to the continuous improvement of market requirements for the pixel and quality of thin mobile phone cameras, the two-piece lens is no longer available. Meet the needs of higher-level photographic lens modules. U.S. Patent No. 7,436,603 provides an imaging lens group composed of three lens structures, which are sequentially composed of a first lens with positive refractive power, a second lens with negative refractive power and A third lens with positive refractive power constitutes the so-called Triplet type. Although this form can correct most of the aberrations produced by the optical system, it has a large demand for the total optical length, resulting in the increase of the lens structure to match the total optical length, making it difficult to meet the needs of thinner and smaller photographic lenses use.

Contents of the invention

The present invention provides a kind of photographing optical lens group, it comprises in order from the object side to the image side: a first lens with positive refractive power; a second lens with negative refractive power, the front surface is concave and the rear surface is Convex, and its front surface, rear surface is provided with aspheric surface; A third lens with negative refractive power, its front surface, rear surface are both concave, and its front surface, rear surface is provided with aspheric surface, and the third lens The lens is provided with an inflection point; in addition, the number of lenses with refractive power in the imaging optical lens group of the present invention is only three. Through the above configuration, the aberration of the imaging optical lens group of the present invention can be effectively corrected, the imaging quality is improved, and At the same time, it has the characteristics of thinning.

In the imaging optical lens group of the present invention, the first lens can be a biconvex lens or a crescent lens with a convex front surface and a concave rear surface; when the first lens is a biconvex lens, the refractive power of the first lens can be effectively increased , so that the total optical length of the imaging optical lens group of the present invention becomes shorter; when the first lens is a convex-concave crescent lens, it is beneficial to correct the astigmatism (Astigmatism) of the imaging optical lens group of the present invention; The three lenses have negative refractive power, and their front surface and back surface are all concave, so that the principal point (Principal Point) of the imaging optical lens group of the present invention is farther away from the imaging surface, and it is beneficial to shorten the optical total of the imaging optical lens group of the present invention. length to maintain the thinness of the lens.

According to one aspect of the present invention, the central thickness of the second lens of the imaging optical lens group of the present invention is CT2, and the focal length of the overall imaging optical lens group is f, and both satisfy the following relational expression:

0.03<CT2/f<0.16;

When CT2/f satisfies the above relational expression, it is beneficial to the moldability and homogeneity of lens plastic injection molding, and at the same time, it is beneficial to shorten the total optical length of the optical system.

According to another aspect of the present invention, the dispersion coefficient (Abbe Number) of the first lens of the present invention's imaging optical lens group is V1, which satisfies the following relational expression:

V1<62;

When V1 satisfies the above relational expression, it is beneficial to correct the astigmatism of the imaging optical lens group of the present invention and improve the imaging quality of the imaging optical lens group.

According to another aspect of the present invention, the radius of curvature of the front surface of the first lens of the imaging optical lens group of the present invention is R1, and the radius of curvature of the rear surface of the first lens is R2, both of which satisfy the following relationship:

0<|R1/R2|<0.4;

When |R1/R2| satisfies the above relational expression, it is beneficial to correct the spherical aberration (Spherical Aberration) in the imaging optical lens group of the present invention.

Description of drawings

FIG. 1 is a schematic diagram of an imaging optical lens group according to a first embodiment of the present invention.

FIG. 2 is an aberration graph of the first embodiment.

FIG. 3 is a schematic diagram of an imaging optical lens group according to a second embodiment of the present invention.

FIG. 4 is an aberration graph of the second embodiment.

FIG. 5 is a schematic diagram of an imaging optical lens group according to a third embodiment of the present invention.

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

FIG. 7 is a schematic diagram of an imaging optical lens group according to a fourth embodiment of the present invention.

FIG. 8 is an aberration graph of the fourth embodiment.

FIG. 9 is Table 1, which is the structural data of the first embodiment.

FIG. 10 is Table 2, which is the aspheric data of the first embodiment.

Fig. 11 is Table 3, which is the structural data of the second embodiment.

FIG. 12 is Table 4, which is the aspherical data of the second embodiment.

Fig. 13 is Table 5, which is the structural data of the third embodiment.

FIG. 14A is Table 6 A, and FIG. 14B is Table 6 B, which are the aspheric data of the third embodiment.

Fig. 15 is Table 7, which is the structural data of the fourth embodiment.

FIG. 16A is Table 8 A, and FIG. 16B is Table 8 B, which are the aspheric data of the fourth embodiment.

Fig. 17 is Table 9, which is the numerical data of the relevant conditional formula of the present invention.

Figure number:

100----first lens 101----front surface

102----rear surface 110----second lens

111----front surface 112----rear surface

120----third lens 121----front surface

122----rear surface 130----aperture

140----infrared filter filter 150----imaging surface

300----first lens 301----front surface

302----rear surface 310----second lens

311----front surface 312----rear surface

320----third lens 321----front surface

322----rear surface 330----aperture

340----infrared filter filter 350----imaging surface

500----first lens 501----front surface

502----rear surface 510----second lens

511----front surface 512----rear surface

520----third lens 521----front surface

522----rear surface 530----aperture

540----infrared filter filter 550----imaging surface

700----first lens 701----front surface

702----rear surface 710----second lens

711----front surface 712----rear surface

720----third lens 721----front surface

722----rear surface 730----aperture

740----infrared filter filter 750----imaging surface

The focal length f of the overall camera optical lens group

The focal length of the first lens f1

The focal length of the second lens f2

The focal length of the third lens is f3

Dispersion coefficient V1 of the first lens

Dispersion coefficient V2 of the second lens

The thickness CT2 of the second lens on the optical axis

Thickness CT3 of the third lens on the optical axis

The distance T12 between the first lens and the second lens on the optical axis

The distance T23 between the second lens and the third lens on the optical axis

The radius of curvature R1 of the front surface of the first lens

The radius of curvature R2 of the rear surface of the first lens

Radius of curvature R5 of the front surface of the third lens

The radius of curvature R6 of the rear surface of the third lens

The total optical length TTL of the camera optical lens group

Imaging height ImgH of camera optical lens group

Detailed ways

A kind of imaging optical lens group provided by the present invention comprises from the object side to the image side in sequence: 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 its front surface, rear surface are both aspherical; a third lens with negative refractive power, its front surface, rear surface are both concave, and its front surface, rear surface are both aspherical, and the third lens The lens is provided with an inflection point. In the imaging optical lens group of the present invention, the first lens can be a biconvex lens or a crescent lens with a convex front surface and a concave rear surface; when the first lens is a biconvex lens, the refractive power of the first lens can be effectively increased , so that the total optical length of the imaging optical lens group of the present invention becomes shorter; when the first lens is a convex-concave crescent lens, it is beneficial to correct the astigmatism (Astigmatism) of the imaging optical lens group of the present invention; The three lenses have negative refractive power, and their front and rear surfaces are all concave, so that the principal point (Principal Point) of the imaging optical lens group of the present invention is farther away from the imaging surface, and it is beneficial to shorten the total optical length of the imaging optical lens group , in order to maintain the thinning of the lens.

In the imaging optical lens group of the present invention, when the first lens is a biconvex lens, the central thickness of the second lens is CT2, and the focal length of the overall imaging optical lens group is f, and both satisfy the following relationship:

0.03<CT2/f<0.16;

When CT2/f satisfies the above relational expression, it is beneficial to the formability and homogeneity of the lens plastic injection molding, and at the same time, it is more beneficial to shorten the total optical length of the imaging optical lens group of the present invention. Specifically, the central thickness CT2 of the second lens of the imaging optical lens group of the present invention satisfies the following relational expression:

0.15mm<CT2<0.38mm.

In the aforementioned imaging optical lens group of the present invention, the focal length of the first lens is f1, and the focal length of the overall imaging optical lens group is f, and both satisfy the following relational expression:

1.30<f/f1<2.00;

When f/f1 satisfies the above relational expression, the configuration of the refractive power of the first lens is relatively balanced; the total optical length of the imaging optical lens group of the present invention can be controlled more effectively, the goal of miniaturization can be maintained, and high-order spherical aberration ( High Order Spherical Aberration) and coma (Coma) are excessively increased to improve imaging quality;

Further, the present invention preferably makes f/f1 satisfy the following relational expression:

1.45<f/f1<1.70.

In the aforementioned imaging optical lens group of the present invention, the focal length of the second lens is f2, and the focal length of the overall imaging optical lens group is f, and both satisfy the following relational expression:

-0.58<f/f2<-0.2;

When f/f2 satisfies the above relational expression, it can be beneficial to the chromatic aberration (Chromatic Aberration) correction of the imaging optical lens group of the present invention.

In the aforementioned imaging 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, both of which satisfy the following relationship:

0<|R1/R2|<0.25;

When |R1/R2| satisfies the above relational expression, it is beneficial to correct the spherical aberration (Spherical Aberration) of the imaging optical lens group of the present invention.

In the foregoing imaging optical lens group of the present invention, the radius of curvature of the front surface of the third lens is R5, and the radius of curvature of the rear surface of the third lens is R6, both of which satisfy the following relationship:

R5/R6<-1.5;

When R5/R6 satisfies the above relationship, it is beneficial to correct the astigmatism and distortion of the imaging optical lens group of the present invention, so as to improve the imaging quality.

In the aforementioned imaging optical lens group of the present invention, the central thickness of the third lens is CT3, which satisfies the following relationship:

0.20<CT3/f<0.40;

When CT3/f satisfies the above relationship, it is beneficial to correct the astigmatism and distortion of the imaging optical lens group of the present invention, and at the same time, it can avoid the back focal length being too short, so that there is not enough space for the rear end mechanism of the lens.

In the aforementioned imaging optical lens group of the present invention, the distance between the first lens and the second lens on the optical axis is T12, and the distance between the second lens and the third lens on the optical axis is T23, satisfying the following relationship:

0.30<T12/T23<2.0;

When T12/T23 satisfies the above relational expression, it is beneficial to correct the off-axis aberration of the imaging optical lens group of the present invention.

In the aforementioned imaging optical lens group of the present invention, the dispersion coefficient (Abbe Number) of the second lens is V2, and it satisfies the following relationship:

V2<25;

When V2 satisfies the above relational expression, the chromatic aberration of the imaging optical lens group of the present invention can be effectively corrected, and the resolution of the imaging optical lens group can be improved.

In the aforementioned imaging optical lens group of the present invention, the subject of the imaging optical lens group is imaged on the electronic photosensitive element, and the total optical length of the imaging optical lens group is TTL, and TTL is defined as the first lens in the imaging optical lens group The distance from the front surface to the imaging surface on the optical axis, the imaging height of the imaging optical lens group is ImgH, and ImgH is defined as half of the diagonal length of the effective pixel area of the electronic photosensitive element, satisfying the following relationship:

TTL/ImgH<1.90;

The above relational expression can maintain the miniaturization characteristic of the imaging optical lens group of the present invention.

On the other hand, in the imaging optical lens group of the present invention, when the first lens is a biconvex lens, the dispersion coefficient (Abbe Number) of the first lens is V1, which satisfies the following relationship:

V1<62;

When V1 satisfies the above relational expression, it is more beneficial to correct the astigmatism of the imaging optical lens group of the present invention and improve the imaging quality of the imaging optical lens group.

In the aforementioned imaging optical lens group of the present invention, the focal length of the first lens is f1, and the focal length of the overall imaging optical lens group is f, and both satisfy the following relationship:

1.30<f/f1<2.00;

When f/f1 satisfies the above relational expression, the configuration of the refractive power of the first lens is relatively balanced; the total optical length of the imaging optical lens group of the present invention can be controlled more effectively, the goal of miniaturization can be maintained, and high-order spherical aberration ( High Order Spherical Aberration) and coma (Coma) are excessively increased to improve imaging quality;

Further, the present invention preferably makes f/f1 satisfy the following relational expression:

1.45<f/f1<1.70.

In the aforementioned imaging optical lens group of the present invention, the focal length of the third lens is f3, and the focal length of the overall imaging optical lens group is f, and both satisfy the following relational expression:

-0.70<f/f3<-0.45;

When f/f3 satisfies the above relational expression, it can avoid that in the imaging optical lens group of the present invention, the angle at which the light is incident on the photosensitive element is too large, and at the same time, the principal point (PrincipalPoint) of the imaging optical lens group can be further away from the imaging surface, It is beneficial to shorten the total optical length of the imaging optical lens group.

In the aforementioned imaging 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, both of which satisfy the following relationship:

0<|R1/R2|<0.25;

When |R1/R2| satisfies the above relational expression, it can be beneficial to correct the spherical aberration (Spherical Aberration) of the aforementioned imaging optical lens group of the present invention.

In the foregoing imaging optical lens group of the present invention, the radius of curvature of the front surface of the third lens is R5, and the radius of curvature of the rear surface of the third lens is R6, both of which satisfy the following relationship:

R5/R6<-1.5;

When R5/R6 satisfies the above relationship, it is beneficial to correct the astigmatism and distortion of the imaging optical lens group of the present invention, so as to improve the imaging quality.

In the aforementioned imaging optical lens group of the present invention, the dispersion coefficient (Abbe Number) of the second lens is V2, and it satisfies the following relationship:

V2<25;

When V2 satisfies the above relational expression, it is beneficial to correct the chromatic aberration (Chromatic Aberration) of the aforementioned imaging optical lens group of the present invention, and improve the resolution (Resolution) of the imaging optical lens group.

In the aforementioned imaging optical lens group of the present invention, the subject of the imaging optical lens group is imaged on the electronic photosensitive element, and the total optical length of the imaging optical lens group is TTL, and TTL is defined as the first lens in the imaging optical lens group The distance from the front surface to the imaging surface on the optical axis, the imaging height of the imaging optical lens group is ImgH, and ImgH is defined as half of the diagonal length of the effective pixel area of the electronic photosensitive element, satisfying the following relationship:

TTL/ImgH<1.90;

The above relational expression can maintain the miniaturization characteristic of the imaging optical lens group of the present invention.

On the other hand, in the imaging optical lens group of the present invention, when the first lens is a convex-concave crescent lens, 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. satisfy the following relation:

0<|R1/R2|<0.4;

When |R1/R2| satisfies the above relational expression, it is more beneficial to correct the spherical aberration (Spherical Aberration) in the imaging optical lens group of the present invention.

In the aforementioned imaging optical lens group of the present invention, the focal length of the first lens is f1, and the focal length of the overall imaging optical lens group is f, and both satisfy the following relationship:

1.30<f/f1<2.00;

When f/f1 satisfies the above relational expression, the configuration of the refractive power of the first lens is relatively balanced; the total optical length of the imaging optical lens group of the present invention can be controlled more effectively, the goal of miniaturization can be maintained, and high-order spherical aberration ( High Order Spherical Aberration) and coma (Coma) are excessively increased to improve imaging quality;

Further, the present invention preferably makes f/f1 satisfy the following relational expression:

1.45<f/f1<1.70.

In the aforementioned imaging optical lens group of the present invention, the focal length of the third lens is f3, and the focal length of the overall imaging optical lens group is f, and both satisfy the following relational expression:

-0.70<f/f3<-0.45;

When f/f3 satisfies the above relational expression, it can avoid that in the imaging optical lens group of the present invention, the angle at which the light is incident on the photosensitive element is too large, and at the same time, the principal point (PrincipalPoint) of the imaging optical lens group can be further away from the imaging surface, It is beneficial to shorten the total optical length of the imaging optical lens group.

In the aforementioned imaging optical lens group of the present invention, the dispersion coefficient (Abbe Number) of the first lens is V1, and it satisfies the following relational expression:

V1<62.

When V1 satisfies the above relational expression, it is more beneficial to correct the astigmatism of the imaging optical lens group of the present invention and improve the imaging quality of the imaging optical lens group.

In the aforementioned imaging optical lens group of the present invention, the dispersion coefficient of the second lens is V2, which satisfies the following relational expression:

V2<25;

When V2 satisfies the above relational expression, the chromatic aberration (Chromatic Aberration) of the aforementioned imaging optical lens group of the present invention can be effectively corrected, thereby improving the resolution (Resolution) of the imaging optical lens group.

In the foregoing imaging optical lens group of the present invention, the radius of curvature of the front surface of the third lens is R5, and the radius of curvature of the rear surface of the third lens is R6, both of which satisfy the following relationship:

R5/R6<-1.5.

When R5/R6 satisfies the above relationship, it is beneficial to correct the astigmatism and distortion of the imaging optical lens group of the present invention, so as to improve the imaging quality.

In the aforementioned imaging optical lens group of the present invention, the subject of the imaging optical lens group is imaged on the electronic photosensitive element, and the total optical length of the imaging optical lens group is TTL, and TTL is defined as the first lens in the imaging optical lens group The distance from the front surface to the imaging surface on the optical axis, the imaging height of the imaging optical lens group is ImgH, and ImgH is defined as half of the diagonal length of the effective pixel area of the electronic photosensitive element, satisfying the following relationship:

TTL/ImgH<1.80;

The above relational expression can maintain the miniaturization characteristic of the imaging optical lens group of the present invention.

The imaging optical lens group of the present invention provides strong positive refractive power through the first lens, and the diaphragm is placed close to the object side of the imaging optical lens group, so that the exit pupil (Exit Pupil) of the imaging optical lens group will be far away from the imaging surface, Therefore, light will be incident on the photosensitive element in a manner close to vertical incidence, which is the telecentric (Telecentric) characteristic of the image side. The sensitivity is improved, and the possibility of vignetting in the imaging optical lens group of the present invention is reduced. In the present invention, the third lens is provided with an inflection point (Inflection Point), which can more effectively suppress the angle at which light from the off-axis field of view is incident on the photosensitive element.

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 before the first lens, then it will focus on the characteristics of telecentricity, and the total optical length of the system can be shorter; The characteristics of the field angle, and at the same time, such a configuration of the aperture position can effectively reduce the sensitivity of the system.

In the imaging optical lens group of the present invention, the material of the lens can be glass or plastic. If the material of the lens is glass, the degree of freedom in the configuration of the refractive power of the system can be increased. If the material of the lens is plastic, the production cost can be effectively reduced. In addition, an aspheric surface can be set on the mirror surface, and the aspheric surface can be easily made into a shape other than a spherical surface, so that more control variables can be obtained to reduce aberrations, thereby reducing the number of lenses used, so the imaging optical lens of the present invention can be effectively reduced. The total optical length of the group.

The imaging optical lens group of the present invention will be described in detail through the following specific embodiments in conjunction with the accompanying drawings.

Please refer to FIG. 1 for the first embodiment of the present invention, and please refer to FIG. 2 for the aberration curve of the first embodiment. The main structure of the imaging optical lens group of the first embodiment is composed of three lenses with refractive power. From the object side to the image side, the order is as follows: a first lens 100 with positive refractive power, the front surface 101 is convex, and the rear surface is convex. The surface 102 is convex, and its material is plastic, and its front surface 101 and rear surface 102 are both aspherical; a second lens 110 with negative refractive power, its front surface 111 is concave, and its rear surface 112 is convex, and its material is plastic , its front surface 111 and rear surface 112 are both aspherical; a third lens 120 with negative refractive power, its front surface 121 is concave, its rear surface 122 is concave, its material is plastic, its front surface 121, its rear surface 122 are all aspheric surfaces, and the rear surface 122 is provided with an inflection point; an aperture 130 is located before the first lens 100; in addition, an infrared filter filter 140 (IR Filter) is included after the third lens 120, which does not Affects the focal length of the imaging optical lens group of the present invention; and an imaging surface 150 is arranged behind the infrared filter 140 .

The equation of the aforementioned 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">\; <figure-callout\; id="2"\; label="Y"\; filenames="H2009101184637E00091.png,H2009101184637E00101.png"\; state="\{\{state\}\}">Y</figure-callout></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 relative height to the tangent plane tangent to the vertex on the aspheric optical axis;

Y: the distance between the point on the aspheric curve and the optical axis;

k: cone coefficient;

Ai: i-th order aspherical coefficient.

In the imaging optical lens group of the first embodiment, the focal length of the first lens 100 is f1, the focal length of the second lens 110 is f2, the focal length of the third lens 120 is f3, and the focal length of the overall imaging optical lens group is f, the relationship It is: f/f1=1.60, f/f2=-0.40, f/f3=-0.53.

In the imaging optical lens group of the first embodiment, the radius of curvature of the front surface 101 of the first lens 100 is R1, the radius of curvature of the rear surface 102 of the first lens 100 is R2, and the radius of curvature of the front surface 121 of the third lens 120 is R5. The radius of curvature of the rear surface 122 of the three lenses 120 is R6, and the relationship is: |R1/R2|=0.04, R5/R6=-8.51.

In the imaging optical lens group of the first embodiment, the thickness of the second lens 110 on the optical axis is CT2, and the thickness of the third lens 120 on the optical axis is CT3, and the relationship is: CT2=0.372mm, CT2/f=0.10 , CT3/f=0.29.

In the imaging optical lens group of the first embodiment, the Abbe Number of the first lens 100 is V1, and the Abbe Number of the second lens 110 is V2, wherein: V1=55.9, V2=23.4.

In the imaging optical lens group of the first embodiment, the distance between the first lens 100 and the second lens 110 on the optical axis is T12, the distance between the second lens 110 and the third lens 120 on the optical axis is T23, and the relationship is: T12/T23 = 0.56.

In the first embodiment of the imaging optical lens group, the total optical length of the imaging optical lens group is TTL, the imaging height of the imaging optical lens group is ImgH, and the relationship is TTL/ImgH=1.78.

The detailed structural data of the first embodiment are shown in Table 1, and the aspheric surface 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.

Please refer to FIG. 3 for the second embodiment of the present invention, and please refer to FIG. 4 for the aberration curve of the second embodiment. The main structure of the imaging optical lens group of the second embodiment is composed of three lenses with refractive power. From the object side to the image side, the order is as follows: a first lens 300 with positive refractive power, the front surface 301 is convex, and the rear surface is convex. The surface 302 is convex, and its material is plastic, and its front surface 301 and rear surface 302 are both aspherical; a second lens 310 with negative refractive power, its front surface 311 is concave, and its rear surface 312 is convex, and its material is Plastic, its front surface 311, rear surface 312 are both aspherical; a third lens 320 with negative refractive power, its front surface 321 is concave, its rear surface 322 is concave, its material is plastic, its front surface 321, rear The surfaces 322 are all aspherical, and the rear surface 322 is provided with an inflection point; an aperture 330 is located in front of the first lens 300; in addition, an infrared filter filter 340 (IR Filter) is included behind the third lens 320, which It does not affect the focal length of the imaging optical lens group of the present invention; and an imaging surface 350 is arranged behind the infrared filter 340 .

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

In the imaging optical lens group of the second embodiment, the focal length of the first lens 300 is f1, the focal length of the second lens 310 is f2, the focal length of the third lens 320 is f3, and the focal length of the overall imaging optical lens group is f, the relationship It is: f/f1=1.96, f/f2=-0.61, f/f3=-0.80.

In the imaging optical lens group of the second embodiment, the radius of curvature of the front surface 301 of the first lens 300 is R1, the radius of curvature of the rear surface 302 of the first lens 300 is R2, and the radius of curvature of the front surface 321 of the third lens 320 is R5. The radius of curvature of the rear surface 322 of the three lenses 320 is R6, and the relationship is: R1/R2=|0.72|, R5/R6=-6.94.

In the second embodiment of the imaging optical lens group, the thickness of the second lens 310 on the optical axis is CT2, and the thickness of the third lens 320 on the optical axis is CT3, and the relationship is: CT2=0.599m, CT2/f=0.16 , CT3/f=0.25.

In the imaging optical lens group of the second embodiment, the Abbe Number of the first lens 300 is V1, and the Abbe Number of the second lens 310 is V2, wherein: V1=55.9, V2=23.4.

In the imaging optical lens group of the second embodiment, the distance between the first lens 300 and the second lens 310 on the optical axis is T12, the distance between the second lens 310 and the third lens 320 on the optical axis is T23, and the relationship is: T12/T23 = 0.50.

In the second embodiment of the imaging optical lens group, the total optical length of the imaging optical lens group is TTL, the imaging height of the imaging optical lens group is ImgH, and the relationship is TTL/ImgH=1.87.

The detailed structural data of the second embodiment are shown in Table 3, and the aspheric surface data are 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.

Please refer to FIG. 5 for the third embodiment of the present invention, and please refer to FIG. 6 for the aberration curve of the third embodiment. The main structure of the imaging optical lens group of the third embodiment is composed of three lenses with refractive power. From the object side to the image side, the order is as follows: a first lens 500 with positive refractive power, the front surface 501 is convex, and the rear surface is convex. The surface 502 is convex, and its material is plastic, and its front surface 501 and rear surface 502 are both aspherical; a second lens 510 with negative refractive power, its front surface 511 is concave, and its rear surface 512 is convex, and its material is Plastic, its front surface 511, rear surface 512 are both aspherical; a third lens 520 with negative refractive power, its front surface 521 is concave, its rear surface 522 is concave, its material is plastic, its front surface 521, rear The surfaces 522 are all aspherical, and the front surface 521 and the rear surface 522 are all provided with inflection points; an aperture 530 is located in front of the first lens 500; an infrared filter filter 540 (IR Filter) is included in the third Behind the lens 520 , it does not affect the focal length of the imaging optical lens group of the present invention; and an imaging surface 550 is arranged behind the infrared filter 540 .

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

In the imaging optical lens group of the third embodiment, the focal length of the first lens 500 is f1, the focal length of the second lens 510 is f2, the focal length of the third lens 520 is f3, and the focal length of the overall imaging optical lens group is f, the relationship It is: f/f1=1.59, f/f2=-0.33, f/f3=-0.64.

In the imaging optical lens group of the third embodiment, the radius of curvature of the front surface 501 of the first lens 500 is R1, the radius of curvature of the rear surface 502 of the first lens 500 is R2, and the radius of curvature of the front surface 521 of the third lens 520 is R5. The radius of curvature of the rear surface 522 of the three lenses 520 is R6, and the relationship is: |R1/R2|=0.07, R5/R6=-2.08.

In the imaging optical lens group of the third embodiment, the thickness of the second lens 510 on the optical axis is CT2, and the thickness of the third lens 520 on the optical axis is CT3, and the relationship is: CT2=0.325mm, CT2/f=0.09 , CT3/f=0.29.

In the imaging optical lens group of the third embodiment, the Abbe Number of the first lens 500 is V1, and the Abbe Number of the second lens 510 is V2, wherein: V1=55.9, V2=23.4.

In the imaging optical lens group of the third embodiment, the distance between the first lens 500 and the second lens 510 on the optical axis is T12, the distance between the second lens 510 and the third lens 520 on the optical axis is T23, and the relationship is: T12/T23 = 0.50.

In the third embodiment of the imaging optical lens group, the total optical length of the imaging optical lens group is TTL, the imaging height of the imaging optical lens group is ImgH, and the relationship is TTL/ImgH=1.70.

The detailed structural data of the third embodiment is shown in Table 5, and the aspheric surface data are shown in Table 6A and Table 6B, 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.

Please refer to FIG. 7 for the fourth embodiment of the present invention, and please refer to FIG. 8 for the aberration curve of the fourth embodiment. The main structure of the imaging optical lens group of the fourth embodiment is composed of three lenses with refractive power. From the object side to the image side in sequence: a first lens 700 with positive refractive power, the front surface 701 of which is convex, and the rear surface The surface 702 is concave, and its material is plastic, and its front surface 701 and rear surface 702 are both aspherical surfaces; a second lens 710 with negative refractive power, its front surface 711 is concave, and its rear surface 712 is convex, and its material is Plastic, its front surface 711, rear surface 712 are both aspherical; a third lens 720 with negative refractive power, its front surface 721 is concave, its rear surface 722 is concave, its material is plastic, its front surface 721, rear The surfaces 722 are all aspherical, and the front surface 721 and the rear surface 722 are all provided with inflection points; an aperture 730 is located in front of the first lens 700; an infrared filter filter 740 (IR Filter) is included in the third After the lens 720), it does not affect the focal length of the imaging optical lens group of the present invention; and an imaging surface 750 is arranged behind the infrared filter 740.

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

In the imaging optical lens group of the fourth embodiment, the focal length of the first lens 700 is f1, the focal length of the second lens 710 is f2, the focal length of the third lens 720 is f3, and the focal length of the overall imaging optical lens group is f, the relationship It is: f/f1=1.52, f/f2=-0.28, f/f3=-0.57.

In the imaging optical lens group of the fourth embodiment, the radius of curvature of the front surface 701 of the first lens 700 is R1, the radius of curvature of the rear surface 702 of the first lens 700 is R2, and the radius of curvature of the front surface 721 of the third lens 720 is R5. The radius of curvature of the rear surface 722 of the three lenses 720 is R6, and the relationship is: |R1/R2|=0.02, R5/R6=-5.36.

In the imaging optical lens group of the fourth embodiment, the thickness of the second lens 710 on the optical axis is CT2, and the thickness of the third lens 720 on the optical axis is CT3, and the relationship is: CT2=0.320mm, CT2/f=0.09 , CT3/f=0.26.

In the imaging optical lens group of the fourth embodiment, the Abbe Number of the first lens 700 is V1, and the Abbe Number of the second lens 710 is V2, wherein: V1=55.9, V2=23.4.

In the imaging optical lens group of the fourth embodiment, the distance between the first lens 700 and the second lens 710 on the optical axis is T12, the distance between the second lens 710 and the third lens 720 on the optical axis is T23, and the relationship is: T12/T23 = 0.50.

In the fourth embodiment, in the imaging optical lens group, the total optical length of the imaging optical lens group is TTL, the imaging height of the imaging optical lens group is ImgH, and the relationship is TTL/ImgH=1.66.

The detailed structural data of the fourth embodiment is shown in Table 7, and its aspheric surface data are shown in Table 8A and Table 8B, 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.

Tables 1 to 8B show the different numerical changes of the embodiments of the imaging optical lens group of the present invention. However, the numerical changes of the various embodiments of the present invention are all obtained from experiments. Even if different numerical values are used, products with the same structure should still belong to the present invention. scope of protection. Table 9 shows the numerical data corresponding to the relevant conditional expressions of the present invention for each embodiment.

The present invention is an imaging optical lens group. The aberration of the imaging optical lens group of the present invention can be effectively corrected through the above-mentioned lens structure and configuration method, the imaging quality can be improved, and it is also conducive to the thinning of the imaging optical lens group of the present invention.

Claims (21)

1. A camera optics lens group, characterized in that it comprises sequentially from the object side to the image side: A first lens with positive refractive power, its front surface and rear surface are both convex; a negative second lens having a concave front surface and a convex rear surface, both of which are aspherical; and A third lens with negative refractive power, the front surface and the back surface are concave, the front surface and the back surface are aspherical, and the third lens is provided with an inflection point; Wherein in the imaging optical lens group, the thickness of the second lens on the optical axis is CT2, the focal length of the overall imaging optical lens group is f, the front surface curvature radius of the first lens is R1 and the rear surface curvature The radius is R2, which satisfies the following relationship: 0.03<CT2/f<0.16; and 0<|R1/R2|<0.25. 2. The imaging optical lens group according to claim 1, wherein the second lens and the third lens are made of plastic material. 3 . The imaging optical lens group according to claim 1 , wherein the lenses with refractive power are only the first lens, the second lens and the third lens. 4 . 4 . The imaging optical lens group according to claim 3 , wherein a diaphragm is arranged in front of the first lens. 5 . 5. imaging optical lens group as claimed in claim 4, is characterized in that, the focal length of described first lens is f1, satisfies following relational expression: 1.30<f/f1<2.00. 6. imaging optical lens group as claimed in claim 5, is characterized in that, the focal length of described second lens is f2, satisfies following relational expression: 1.45<f/f1<1.70; and -0.58<f/f2<-0.2. 7. The imaging optical lens group as claimed in claim 4, wherein the front surface radius of curvature of the third lens is R5 and the rear surface radius of curvature is R6, satisfying the following relationship: R5/R6<-1.5. 8. The imaging optical lens group as claimed in claim 4, wherein the thickness of the third lens on the optical axis is CT3, which satisfies the following relational expression: 0.20<CT3/f<0.40. 9. The imaging optical lens group according to claim 8, wherein the distance between the first lens and the second lens on the optical axis is T12, and the distance between the second lens and the third lens is T12. The distance on the optical axis is T23, which satisfies the following relationship: 0.3<T12/T23<2.0. 10. imaging optical lens group as claimed in claim 4, is characterized in that, the dispersion coefficient of described second lens is V2, satisfies following relational expression: V2<25. 11. The imaging optical lens group as claimed in claim 3, wherein the thickness of the second lens on the optical axis is CT2, which satisfies the following relational expression: 0.15mm<CT2<0.38mm. 12. The imaging optical lens group according to claim 3, wherein the subject of the imaging optical lens group is imaged on an electronic photosensitive element, and the total optical length of the imaging optical lens group is TTL, and the The imaging height of the imaging optical lens group is ImgH, TTL is defined as the distance from the front surface of the first lens in the imaging optical lens group to the imaging surface on the optical axis, and ImgH is defined as half of the diagonal length of the effective pixel area of the electronic photosensitive element , satisfying the following relation: TTL/ImgH<1.90. 13. An imaging optical lens group, characterized in that it comprises sequentially from the object side to the image side: A first lens with positive refractive power, its front surface and rear surface are both convex; a negative second lens having a concave front surface and a convex rear surface, both of which are aspherical; and A third lens with negative refractive power, the front surface and the back surface are concave, the front surface and the back surface are aspherical, and the third lens is provided with an inflection point; Wherein the dispersion coefficient of the first lens is V1, 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, satisfying the following relationship: V1<62; and 0<|R1/R2|<0.25. 14. The imaging optical lens group according to claim 13, wherein the second lens and the third lens are made of plastic material. 15. The imaging optical lens group according to claim 13, wherein the lenses with refractive power are only the first lens, the second lens and the third lens. 16. The imaging optical lens group according to claim 15, wherein a diaphragm is arranged in front of the first lens. 17. The imaging optical lens group as claimed in claim 16, wherein the focal length of the first lens is f, and the focal length of the overall imaging optical lens group is f, which satisfies the following relational expression: 1.30<f/f1<2.00. 18. The imaging optical lens group as claimed in claim 17, wherein the focal length of the third lens is f3, which satisfies the following relational expression: 1.45<f/f1<1.70; and -0.70<f/f3<-0.45. 19. The imaging optical lens group as claimed in claim 16, wherein the radius of curvature of the front surface of the third lens is R5 and the radius of curvature of the rear surface of the third lens is R6, satisfying the following relationship: R5/R6<-1.5. 20. The imaging optical lens group according to claim 15, wherein the dispersion coefficient of the second lens is V2, which satisfies the following relational expression: V2<25. 21. The imaging optical lens group according to claim 15, wherein the subject of the imaging optical lens group is imaged on an electronic photosensitive element, and the total optical length of the imaging optical lens group is TTL, and the The imaging height of the imaging optical lens group is ImgH, TTL is defined as the distance from the front surface of the first lens in the imaging optical lens group to the imaging surface on the optical axis, and ImgH is defined as half of the diagonal length of the effective pixel area of the electronic photosensitive element , satisfying the following relation: TTL/ImgH<1.90.

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