CN104007540B - Optical imaging lens and apply the electronic installation of this optical imaging lens - Google Patents

Abstract

The present invention relates to optical imaging lens and the electronic installation with optical imaging lens. Optical imaging lens is by thing side to comprising a first lens as side, and its thing side has the convex surface part of optical axis near zone and the convex surface part of circumference near zone; One aperture; One second lens, its thing side has the concave surface portion of the concave surface portion circumference near zone of optical axis near zone, and it has the convex surface part of axle near zone and the convex surface part of circumference near zone as side; And one the 3rd lens, its thing side has the concave surface portion of circumference near zone, and it has the convex surface part of the concave surface portion circumference near zone of optical axis near zone as side; And meet 1.4≤T2/AAG. Electronic installation of the present invention, comprising: a casing and an image module, and comprise an optical imaging lens of the present invention, lens barrel, a module back seat unit, a substrate, and an image sensor. Electronic installation of the present invention and its optical imaging lens maintain favorable optical performance, and effectively shorten lens length.

Description

Optical imaging lens and electronic device using same

Technical Field

The present invention relates to an optical lens, and more particularly, to an optical imaging lens and an electronic device using the same.

Background

In recent years, the popularity of portable electronic products such as mobile phones and digital cameras has led to the rapid development of image module related technologies, the image module mainly includes components such as an optical imaging lens, a module backseat unit (modular) and a sensor (sensor), and the miniaturization of the image module is becoming more and more demanding due to the trend of the mobile phones and digital cameras toward being thin and light, and with the technological progress and size reduction of a photosensitive coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS), the optical imaging lens loaded in the image module needs to be correspondingly shortened in length, but in order to avoid the reduction of the photographing effect and quality, good optical performance is still considered when the length of the optical imaging lens is shortened.

US7436605 and US7813056 both disclose an optical lens assembly composed of three lenses, however, the refractive indexes of the first two lenses are negative and positive, and such an arrangement cannot achieve good optical characteristics, and the overall lens length is as high as 7-8 mm, and the overall device cannot achieve the effects of thinness and lightness.

Therefore, it is an urgent issue to solve in the art how to effectively reduce the system length of the optical lens while maintaining sufficient optical performance.

Disclosure of Invention

Therefore, the present invention is directed to an optical imaging lens capable of maintaining good optical performance even when the length of the lens system is shortened.

According to the present invention, an optical imaging lens includes, in order from an object side to an image side along an optical axis, a first lens element, an aperture stop, a second lens element and a third lens element, each having a refractive index, and having an object-side surface facing the object side and passing an imaging light beam therethrough and an image-side surface facing the image side and passing the imaging light beam therethrough. The first lens element with positive refractive index has a convex object-side surface, a convex part near the optical axis and a convex part near the circumference.

The second lens element with positive refractive power has a concave object-side surface, a concave portion in an area near the optical axis and a concave portion in an area near the circumference, and a convex image-side surface with a convex portion in an area near the optical axis and a convex portion in an area near the circumference.

The third lens element with negative refractive index has a concave surface on the object-side surface and a concave surface on the optical axis, and a convex surface on the peripheral region.

Wherein, the optical imaging lens only comprises the three lenses with refractive indexes

T2/AAG with the ratio of 1.4 to less than or equal to that of the conditional expression (1);

t2 is the thickness of the second lens on the optical axis, and AAG is the sum of the widths of two air gaps between the first to third lenses on the optical axis.

Secondly, the invention can selectively control the ratio of partial parameters to satisfy other conditional expressions, such as:

controlling a sum of widths of two air gaps between the first to third lenses on an optical axis (expressed as AAG) and a thickness of the third lens on the optical axis (expressed as T3) to satisfy:

AAG/T3 is not less than 0.9 and the conditional expression (2);

or the thickness of the second lens on the optical axis (represented by T2) and the width of the air gap between the first lens and the second lens on the optical axis (represented by AG12) are controlled to satisfy the following conditions:

T2/AG12 is not less than 1.7 and is represented by the following conditional formula (3);

or the sum of the thicknesses of three lenses (expressed by ALT) of the first lens to the third lens on the optical axis and the back focal length of the optical imaging lens are controlled, namely the distance (expressed by BFL) between the image side surface of the third lens and the imaging surface on the optical axis satisfies the following conditions:

the ALT/BFL is less than or equal to 2.0, and the conditional expression (4);

or controlling the focal length of the first lens (represented by f 1) and the focal length of the third lens (represented by f 3) to satisfy the following conditions:

the conditional expression (5) is more than or equal to 1.9 | f1/f | + | f3/f |;

or controlling the ALT and the thickness of the second lens on the optical axis (represented by T2) to satisfy the following conditions:

ALT/T2 is less than or equal to 2.65, conditional expression (6);

or controlling BFL and T2 to satisfy:

BFL/T2 is more than or equal to 1.1, and the conditional formula (7) is adopted;

or controlling ALT and T3 to satisfy:

ALT/T3 is not less than 4.0 and is represented by the formula (8);

or controlling ALT and AAG to satisfy:

ALT/AAG is more than or equal to 2.7 and less than or equal to 7.0, and the conditional expression (9);

or the abbe number (represented by v 1) of the first lens and the abbe number (represented by v 2) of the second lens are controlled to satisfy:

the conditional expression (10) of | v1-v2| ≦ 10.0;

or controlling T2 and AG12 to satisfy:

T2/AG12 is not less than 1.7 and is represented by the following conditional formula (11);

or the v1 and the abbe number (abbe number) (shown as v 3) of the third lens satisfy:

the absolute value v1-v3 is more than or equal to 20.0 and less than or equal to 50.0, and the conditional expression (12) is adopted;

or the AG12 and the thickness of the first lens on the optical axis (indicated by T1) are controlled to satisfy the following conditions:

AG12/T1 with the ratio of 0.5 to less than or equal to AG12/T1 as the conditional expression (13);

or controlling AAG and T1 to satisfy:

AAG/T1 is not less than 0.6, and the conditional expression (14);

or controlling T1 and T3 to satisfy:

T1/T3 is not less than 1.3 and is represented by the formula (15);

or controlling T2 and T1 to satisfy:

T2/T1 is not less than 1.4 and is represented by the formula (16);

or controlling ALT and AG12 to satisfy:

ALT/AG12 is not less than 3.3 and not more than 10.0, conditional expression (17).

The above-listed exemplary limiting conditions can be optionally combined and applied in the embodiments of the present invention, and are not limited thereto.

In addition to the above conditional expressions, the present invention can also be implemented to design additional features such as concave-convex curved surface arrangement of other lenses for a single lens or a plurality of lenses to enhance the control of the system performance and/or resolution, for example, the object-side surface of the third lens further has a convex surface portion located in the vicinity of the optical axis. It should be noted that these details need not be selectively combined and applied in other embodiments of the present invention without conflict, and are not limited thereto.

The optical imaging lens has the beneficial effects that: the positive refractive index of the second lens element can provide the refractive index required by the whole lens system, the positive refractive index of the first lens element can assist in sharing the positive refractive index required by the whole lens system, thereby reducing the difficulty in designing and manufacturing the whole lens system, and the negative refractive index of the third lens element has the effect of correcting aberration; in addition, the aperture is arranged between the first lens and the second lens to help improve the imaging quality. The object-side surface of the first lens element is convex to assist in collecting imaging light, the object-side surface of the second lens element is concave, the image-side surface of the second lens element is convex, the concave surface of the third lens element is in the vicinity of the object-side surface, the concave surface of the image-side surface is in the vicinity of the optical axis, and the convex surface of the periphery is in the vicinity of the optical axis. In addition, through the numerical control of the above parameters, the designer can be assisted to design an optical imaging lens with good optical performance, effectively shortened overall length, and feasible technology.

The present invention provides an electronic device according to the above-mentioned optical imaging lens, comprising: the shell and the image module are arranged in the shell. The image module comprises any optical imaging lens, a lens cone for the optical imaging lens, a module rear seat unit for the lens cone, a substrate for the module rear seat unit, and an image sensor arranged on the substrate and positioned at the image side of the optical imaging lens.

The electronic device has the beneficial effects that: by loading the image module with the optical imaging lens in the electronic device, the imaging lens can still provide the advantage of good optical performance under the condition of shortening the system length, and a thinner and lighter electronic device can be manufactured under the condition of not sacrificing the optical performance, so that the invention has good practical performance, is beneficial to the structural design of thinning and shortening, and can meet the consumption requirement of higher quality.

Drawings

FIG. 1 is a schematic diagram illustrating a lens structure;

FIG. 2 is a schematic configuration diagram illustrating a first embodiment of an optical imaging lens according to the present invention;

FIG. 3 is a diagram of longitudinal spherical aberration and various aberrations of the first embodiment;

FIG. 4 is a table diagram illustrating optical data for each lens of the first embodiment;

FIG. 5 is a table diagram illustrating aspherical coefficients of the lenses of the first embodiment;

FIG. 6 is a schematic configuration diagram illustrating a second embodiment of an optical imaging lens according to the present invention;

FIG. 7 is a diagram of longitudinal spherical aberration and various aberrations of the second embodiment;

FIG. 8 is a table diagram illustrating optical data for each lens of the second embodiment;

FIG. 9 is a table diagram illustrating aspherical coefficients of the lenses of the second embodiment;

FIG. 10 is a schematic configuration diagram illustrating a third embodiment of an optical imaging lens according to the invention;

FIG. 11 is a longitudinal spherical aberration and various aberrations diagram of the third embodiment;

FIG. 12 is a table diagram illustrating optical data for each lens of the third embodiment;

FIG. 13 is a table diagram illustrating aspherical coefficients of the lenses of the third embodiment;

FIG. 14 is a schematic configuration diagram illustrating a fourth embodiment of an optical imaging lens according to the invention;

FIG. 15 is a longitudinal spherical aberration and various aberrations diagram of the fourth embodiment;

FIG. 16 is a table diagram illustrating optical data for each lens of the fourth embodiment;

FIG. 17 is a table diagram illustrating aspherical coefficients of the lenses of the fourth embodiment;

FIG. 18 is a schematic configuration diagram illustrating a fifth embodiment of an optical imaging lens according to the present invention;

FIG. 19 is a longitudinal spherical aberration and various aberrations diagram of the fifth embodiment;

FIG. 20 is a table diagram illustrating optical data for each lens of the fifth embodiment;

FIG. 21 is a table diagram illustrating aspherical coefficients of the lenses of the fifth embodiment;

FIG. 22 is a schematic configuration diagram illustrating a sixth embodiment of an optical imaging lens according to the invention;

FIG. 23 is a longitudinal spherical aberration and various aberrations diagram of the sixth embodiment;

FIG. 24 is a table diagram illustrating optical data for each lens of the sixth embodiment;

FIG. 25 is a table diagram illustrating aspherical coefficients of the lenses of the sixth embodiment;

FIG. 26 is a table diagram illustrating optical parameters of the first to sixth embodiments of the three-piece optical imaging lens;

FIG. 27 is a schematic cross-sectional view illustrating a first embodiment of an electronic device according to the present invention; and

fig. 28 is a schematic cross-sectional view illustrating an electronic device according to a second embodiment of the invention.

[ notation ] to show

10 optical imaging lens

2 aperture

3 first lens

31 side of the object

311 convex part

312 convex part

32 image side

321 concave part

322 concave part

323 convex surface part

4 second lens

41 side of the object

411 concave part

412 concave part

42 image side

421 convex part

422 convex surface part

5 third lens

51 side of the object

511 convex part

513 concave part

512 concave part

Side surface of 52 figure

521 concave part

522 concave part

6 optical filter

61 side of the object

62 image side

100 image plane

I optical axis

1 electronic device

11 casing

12 image module

120 module backseat unit

121 lens backseat

122 image sensor backseat

123 first base

124 second seat

125 coil

126 magnetic assembly

130 image sensor

21 lens barrel

II, III axes

A, B, C, E region

Detailed Description

The invention is further described with reference to the accompanying drawings for illustrating the various embodiments. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the embodiments. With these references in mind, one skilled in the art will understand that other embodiments are possible and that the advantages of the invention are realized. The components in the drawings are not to scale and similar components are designated by the same reference numerals.

In the present specification, the phrase "a lens element has positive refractive index (or negative refractive index)" refers to the phrase that the lens element has positive refractive index (or negative refractive index) in the region near the optical axis. "the object-side surface (or image-side surface) of a lens includes a convex surface portion (or concave surface portion) in a region" means that the region is more "outwardly convex" (or "inwardly concave") in a direction parallel to the optical axis than an outer region immediately radially outside the region. Taking fig. 1 as an example, where I is the optical axis and such a lens is radially symmetrical to each other with the optical axis I as the axis of symmetry, the object-side surface of the lens has a convex surface portion in the a region, a concave surface portion in the B region and a convex surface portion in the C region, because the a region is more convex toward the direction parallel to the optical axis than the outer region (i.e., the B region) immediately radially adjacent to the a region, the B region is more concave toward the inside than the C region, and the C region is also more convex toward the outside than the E region similarly. The "area near the circumference" refers to an area near the circumference, i.e. the area C in the figure, of the curved surface on the lens for passing only the imaging light rays, wherein the imaging light rays include a chief ray (chiefly) Lc and a marginal ray (marginally) Lm. "the region located near the optical axis" refers to the region near the optical axis of the curved surface through which only the imaging light passes, i.e., region a in the figure. In addition, the lens further includes an extension portion E for assembling the lens in an optical imaging lens, and an ideal imaging light does not pass through the extension portion E, but the structure and shape of the extension portion E are not limited thereto.

The optical imaging lens of the present invention is a fixed focus lens, and is composed of a first lens element, an aperture, a second lens element and a third lens element sequentially disposed along an optical axis from an object side to an image side, wherein each lens element has a refractive index, and has an object side surface facing the object side and allowing the imaging light to pass therethrough and an image side surface facing the image side and allowing the imaging light to pass therethrough. The optical imaging lens of the invention only has the three lenses with the refractive indexes in total, and can provide good optical performance by designing the detailed characteristics of each lens. The detailed characteristics of each lens are as follows: the first lens element with positive refractive power has a convex object-side surface, a convex surface portion located in the vicinity of the optical axis and a convex surface portion located in the vicinity of the circumference, and a concave image-side surface having a concave surface portion located in the vicinity of the optical axis and a concave surface portion located in the vicinity of the circumference.

The second lens element with positive refractive power has a concave object-side surface, a concave portion in an area near the optical axis and a concave portion in an area near the circumference, and a convex image-side surface with a convex portion in an area near the optical axis and a convex portion in an area near the circumference.

The third lens element with negative refractive power has an object-side surface with a convex surface in a region near the optical axis and a concave surface in a region near the circumference, but the shape of the region near the optical axis is not limited thereto.

The optical imaging lens only comprises the three lenses with the refractive indexes.

The characteristics of the lenses designed herein mainly consider the optical characteristics and the lens length of the optical imaging lens, for example: the second lens element has a positive refractive index for providing the total required refractive index of the lens, the first lens element has a positive refractive index for assisting in sharing the total required positive refractive index of the lens, thereby reducing the difficulty in designing and manufacturing the lens, and the third lens element has a negative refractive index for correcting aberration; in addition, the aperture is arranged between the first lens and the second lens, so that the imaging quality can be improved. The object-side surface of the first lens element is convex to assist in collecting imaging light, the object-side surface of the second lens element is concave, the image-side surface of the second lens element is convex, the concave surface of the third lens element is in the vicinity of the object-side surface, the concave surface of the image-side surface is in the vicinity of the optical axis, and the convex surface of the periphery is in the vicinity of the optical axis. In addition, through the numerical control of the following parameters, the designer can be assisted to design an optical imaging lens with good optical performance, effectively shortened overall length, and feasible technology.

Furthermore, in the embodiment of the present invention, the ratio of the optional additional control parameters satisfies other conditional expressions, such as:

controlling the thickness of the second lens on the optical axis (expressed by T2) and the sum of the widths of two air gaps between the first to third lenses on the optical axis (expressed by AAG) to satisfy:

T2/AAG with the ratio of 1.4 to less than or equal to that of the conditional expression (1);

t2 is the thickness of the second lens on the optical axis, and AAG is the sum of the widths of two air gaps between the first to third lenses on the optical axis I.

Secondly, the invention can selectively control the ratio of partial parameters to satisfy other conditional expressions, such as:

controlling a sum of widths of two air gaps between the first to third lenses on an optical axis (expressed as AAG) and a thickness of the third lens on the optical axis (expressed as T3) to satisfy:

AAG/T3 is not less than 0.9 and the conditional expression (2);

or the thickness of the second lens on the optical axis (represented by T2) and the width of an air gap between the first lens and the second lens on the optical axis I (represented by AG12) are controlled to satisfy the following conditions:

T2/AG12 is not less than 1.7 and is represented by the following conditional formula (3);

or the sum of the thicknesses of three lenses (expressed by ALT) of the first lens to the third lens on the optical axis and the back focal length of the optical imaging lens are controlled, namely the distance (expressed by BFL) between the image side surface of the third lens and the imaging surface on the optical axis satisfies the following conditions:

the ALT/BFL is less than or equal to 2.0, and the conditional expression (4);

or controlling the focal length of the first lens (represented by f 1) and the focal length of the third lens (represented by f 3) to satisfy the following conditions:

the conditional expression (5) is more than or equal to 1.9 | f1/f | + | f3/f |;

or controlling the ALT and the thickness of the second lens on the optical axis (represented by T2) to satisfy the following conditions:

ALT/T2 is less than or equal to 2.65, conditional expression (6);

or controlling BFL and T2 to satisfy:

BFL/T2 is more than or equal to 1.1, and the conditional formula (7) is adopted;

or controlling ALT and T3 to satisfy:

ALT/T3 is not less than 4.0 and is represented by the formula (8);

or controlling ALT and AAG to satisfy:

ALT/AAG is more than or equal to 2.7 and less than or equal to 7.0, and the conditional expression (9);

or the first lens abbe number (represented by v 1) and the second lens abbe number (represented by v 2) are controlled to satisfy:

the conditional expression (10) of | v1-v2| ≦ 10.0;

or controlling T2 and AG12 to satisfy:

T2/AG12 is not less than 1.7 and is represented by the following conditional formula (11);

or the v1 and the third lens abbe number (shown as v 3) satisfy:

the absolute value v1-v3 is more than or equal to 20.0 and less than or equal to 50.0, and the conditional expression (12) is adopted;

or the AG12 and the thickness of the first lens on the optical axis (indicated by T1) are controlled to satisfy the following conditions:

AG12/T1 with the ratio of 0.5 to less than or equal to AG12/T1 as the conditional expression (13);

or controlling AAG and T1 to satisfy:

AAG/T1 is not less than 0.6, and the conditional expression (14);

or controlling T1 and T3 to satisfy:

T1/T3 is not less than 1.3 and is represented by the formula (15);

or controlling T2 and T1 to satisfy:

T2/T1 is not less than 1.4 and is represented by the formula (16);

or controlling ALT and AG12 to satisfy:

ALT/AG12 is not less than 3.3 and not more than 10.0, conditional expression (17).

The above-listed exemplary definitions can be optionally combined and applied in the embodiments of the present invention, and are not limited thereto.

The T2/AAG value is designed with a view to the positive refractive power required by the T2 for the whole, T2 is the thickness of the second lens element along the optical axis, and since the T2 is the positive refractive power required by the whole, the T2 value should be larger, the reduction of T2 is more limited than other parameters, and the reduction of the sum of the width values of the gaps (i.e., AAG) is relatively easy, so the T2/AAG should be designed to be larger, and the T2/AAG should be greater than or equal to 1.4 to satisfy the conditional expression (1), and preferably between 1.4 and 3.0.

The AAG/T3 value is designed by focusing on the fact that AAG is the sum of the air gaps between the first to third lenses, and maintains a certain gap value, which is helpful to adjust the light to a proper degree and then enter the next lens, therefore AAG should maintain a certain width value, and T3 should be reduced to make the entire lens thin, therefore AAG/T3 should be designed to be large, and AAG/T3 should be greater than or equal to 0.9 to satisfy the conditional expression (2), and preferably between 0.9 and 2.0.

As mentioned above, since T2 is the thickness of the second lens element along the optical axis, T2 imposes a large limit on the reduction of T2 compared to other parameters because of the overall required positive refractive index, and the reduction of AG12 is relatively easy, so T2/AG12 should be designed to be large, and T2/AG12 is preferably greater than or equal to 1.7 to satisfy the condition (3), and preferably between 1.7 and 4.0.

The design of ALT/BFL value is to look at ALT as the total thickness of the first to third lens along the optical axis, BFL is the back focal length of an optical lens, that is, the distance between the image side surface of the third lens along the optical axis and the image plane, and the values should maintain proper proportion relation to avoid the values being too large to facilitate thinning or too small to increase the difficulty of manufacturing or assembling, and the ALT/BFL is recommended to be less than or equal to 2.0 to satisfy the condition (4) and preferably between 1.0 and 2.0.

The design of | f1/f + | f3/f | focuses on that f1 and f3 are the focal length of the first and third lenses, respectively, and f is the focal length of the whole optical lens, when the refractive indexes of the first and third lenses are too strong, the absolute values of f1 and f3 will be smaller, resulting in | f1/f + | f3/f | will also be smaller, while too strong refractive index will also increase the difficulty in lens manufacture, so as to make the lens easier to manufacture, the | f1/f | + | f3/f | should be larger, and | f1/f | + | f3/f | is suggested to be greater than or equal to 1.9 to satisfy the condition (5) and to be between 1.9 and 6.0.

As mentioned above, T2 is the thickness of the second lens element along the optical axis, and since T2 contributes to the overall required positive refractive index, the reduction of T2 is more limited than other parameters, and ALT is the sum of the thicknesses of the first to third lens elements along the optical axis, so that ALT/T2 should be designed smaller, and ALT/T2 is preferably less than or equal to 2.65 to satisfy the condition (6), and preferably between 1.5 and 2.65.

As mentioned above, T2 is the thickness of the second lens element along the optical axis, and T2 is responsible for the overall required positive refractive index, so that the reduction of T2 is greatly limited compared to other parameters, and BFL is the back focal length of the optical lens, i.e. the distance between the image-side surface of the third lens element and the image-plane along the optical axis, and the values should be maintained in a proper ratio relationship to avoid the values being too large to facilitate thinning or too small to increase the difficulty in manufacturing or assembling, and BFL/T2 is preferably greater than or equal to 1.1 to satisfy the conditional expression (7) and is preferably between 1.1 and 2.0.

The ALT/T3 value is designed by focusing on that T3 is the thickness of the third lens element along the optical axis, ALT is the sum of the thicknesses of the first to third lens elements along the optical axis, and the ratio between these values should be maintained properly to avoid the values being too large to facilitate thinning or too small to increase the difficulty in manufacturing or assembling, and ALT/T3 is recommended to be 4.0 or more to satisfy the conditional expression (8), and preferably between 4.0 and 7.0.

The ALT/AAG value is designed by focusing on that ALT is the sum of the thicknesses of three lenses of the first lens, the second lens and the third lens on the optical axis, and AAG is the sum of the widths of two air gaps between the first lens and the third lens on the optical axis, and the values should be in a proper proportion relationship to avoid that the values are too large to facilitate thinning or too small to improve the difficulty in manufacturing or assembling, so that the ALT/AAG value is preferably between 2.7 and 7.0 to satisfy the condition (9), and the ALT/AAG value is preferably between 2.7 and 5.5.

The design of the values of | v1-v2|, and | v1-v3| focuses on that v1, v2, and v3 are the abbe numbers of the first, second, and third lenses, respectively, and when the difference between the first and second lenses is small and the difference between the second and third lenses is between 20 and 50, the entire lens can have a better capability of eliminating chromatic aberration. I v1-v 2I suggest that it should be less than or equal to 10 to satisfy conditional expression (10). The value of | v1-v3| is preferably 20.0-50.0 to satisfy the condition (12).

The T2/AG12 value is designed with a focus on T2 as the thickness of the second lens element along the optical axis, and since T2 bears the overall required positive refractive index, the reduction of T2 is greatly limited compared to other parameters, while the reduction of AG12 and other values is relatively easy, so T2/AG12 should be designed to be larger, and T2/AG12 should be greater than or equal to 1.7 to satisfy the conditional expression (11), and preferably between 1.7 and 4.0.

The AG12/T1 value is designed with a view to the gap value between the first and second lenses (i.e. AG12) being not too small to affect the assembly, so AG12 should maintain a certain width value to help adjust the light to a proper degree and then enter the next lens, and T1 should be reduced to make the overall lens thin, so AG12/T1 should be designed to be larger, and AG12/T1 should be greater than or equal to 0.5 to satisfy the condition (13), and preferably between 0.5 and 1.2.

The AAG/T1 value is designed by focusing on the fact that AAG is the sum of the air gaps between the first to third lenses, and maintains a certain gap value, which is helpful to adjust the light to a proper degree and then enter the next lens, therefore AAG should maintain a certain width value, and T1 should be reduced to make the entire lens thin, therefore AAG/T1 should be designed to be large, and AAG/T1 should be greater than or equal to 0.6 to satisfy the conditional expression (14), and preferably between 0.6 and 1.5.

The T1/T3 value is designed by focusing on T1 and T3 as the thicknesses of the first and third lenses along the optical axis, respectively, and the values should be in a proper proportional relationship to avoid the situation that the values are too large to facilitate thinning or too small to increase the difficulty in manufacturing or assembling, and the first lens has a larger optical effective diameter and can be made thicker, but too thick to make the optical lens longer, and therefore still needs to be limited within a certain size, and the third lens has a smaller optical effective diameter and can be made thinner, so that when the two satisfy the relationship, the thickness of the first lens can be limited within a proper size, and the first and third lenses have better configurations. T1/T3 is preferably 1.3 or more to satisfy the conditional expression (15), and more preferably 1.3 to 2.5.

The design of the T2/T1 value focuses on that T2 is the thickness of the second lens element along the optical axis, and since the second lens element bears the overall required positive refractive index, the reduction of T2 is more limited than other parameters, and the reduction of the T1 value is relatively easy, so that T2/T1 should be larger to design T2/T1, it is recommended that the T2/T1 should be greater than or equal to 1.4 to satisfy the conditional expression (16), and preferably between 1.4 and 2.0.

The design of ALT/AG12 value is focused on the fact that the total thickness of each lens along the optical axis (i.e. ALT) can be effectively reduced, which will help to shorten the total length of the system, and ALT/AG12 suggests that the total thickness should be 3.6-10.0 to satisfy the conditional expression (17) to avoid the thickness of any lens or the gap being too large to be beneficial to the thinning of the whole body, and ALT/AG12 is preferably 3.6-6.5.

In addition to the above conditional expressions, the present invention can also design additional features such as concave-convex curved surface arrangement of other more lenses for a single lens or a plurality of lenses to enhance the control of system performance and/or resolution. It should be noted that these details need not be selectively combined and applied in other embodiments of the present invention without conflict, and are not limited thereto.

To illustrate that the present invention does provide good optical performance, a number of examples and detailed optical data thereof are provided below. Referring to fig. 2 and 4, the optical imaging lens 10 according to the first embodiment of the present invention includes, in order from an object side to an image side along an optical axis I, a first lens element 3, an aperture 2, a second lens element 4, a third lens element 5, and a filter 6. When light emitted from an object enters the optical imaging lens 10, and passes through the aperture 2, the first lens 3, the second lens 4, the third lens 5, and the filter 6, an image is formed on an imaging surface 100 (ImagePlane). The filter 6 is an infrared filter (IRCutFilter) for preventing infrared rays in light from transmitting to the image plane 100 to affect the image quality. It should be noted that the object side is toward the object to be photographed, and the image side is toward the imaging plane 100.

The first lens element 3, the second lens element 4, the third lens element 5, and the filter 6 each have an object-side surface 31, 41, 51, 61 facing the object side and allowing the imaging light to pass therethrough, and an image-side surface 32, 42, 52, 62 facing the image side and allowing the imaging light to pass therethrough. Wherein the object side surfaces 31, 41, 51 and the image side surfaces 32, 42, 52 are aspheric.

In addition, in order to satisfy the requirement of light weight of the product, the first lens element 3 to the third lens element 5 are all made of plastic materials with refractive index, but the materials of the first lens element 3 to the third lens element 5 are not limited thereto.

The first lens element 3 has a positive refractive index. The object-side surface 31 of the first lens element 3 is a convex surface, and has a convex portion 311 located in the vicinity of the optical axis I and a convex portion 312 located in the vicinity of the circumference, and the image-side surface 32 of the first lens element 3 is a concave surface, and has a concave portion 321 located in the vicinity of the optical axis I and a concave portion 322 located in the vicinity of the circumference, but the shape of the surface of the image-side surface is not limited thereto.

The second lens element 4 has a positive refractive index. The object-side surface 41 of the second lens element 4 is concave and has a concave portion 411 located in the vicinity of the optical axis I and a concave portion 412 located in the vicinity of the circumference, and the image-side surface 42 of the second lens element 4 is convex and has a convex portion 421 located in the vicinity of the optical axis I and a convex portion 422 located in the vicinity of the circumference.

The third lens element 5 with negative refractive power has a convex portion 511 located in the vicinity of the optical axis I and a convex portion 512 located in the vicinity of the circumference of the object-side surface 51 of the third lens element 5, but the shape of the vicinity of the optical axis is not limited thereto, and the image-side surface 52 of the third lens element 5 has a concave portion 521 located in the vicinity of the optical axis I and a convex portion 522 located in the vicinity of the circumference of the object-side surface.

In the first embodiment, the optical imaging lens has only three lenses with refractive indexes.

Other detailed optical data of the first embodiment is shown in fig. 4, and the overall system focal length (EFL) of the first embodiment is 1.5558mm, the half-field-of-view (HFOV) is 37.080 °, the aperture value (Fno) is 2.8, and the system length is 2.8742 mm. The system length is a distance from the object side surface 31 of the first lens element 3 to an image plane 100 on an optical axis I.

In addition, a total of six surfaces of the object-side surface 31, 41, 51 and the image-side surface 32, 42, 52 of the first lens element 3, the second lens element 4 and the third lens element 5 are aspheric surfaces defined by the following formulas:

$Z\left(Y\right)=\frac{Y^2}{R}/(1+\sqrt{1-(1+K)\frac{Y^2}{R^2}})+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{a}_{2i}\×Y^{2i}---\left(1\right)$

wherein:

y: the distance between a point on the aspheric curve and the optical axis I;

z: the depth of the aspheric surface (the vertical distance between the point on the aspheric surface that is Y from the optical axis I and the tangent plane tangent to the vertex on the optical axis I);

r is the curvature radius of the lens surface;

k: cone coefficient (Conicconstant);

a_2i: aspheric coefficients of order 2 i.

The aspheric coefficients of the object side surface 31 of the first lens element 3 to the image side surface 52 of the third lens element 5 in equation (1) are shown in fig. 5.

In addition, the relationship among the important parameters in the optical imaging lens 10 of the first embodiment is as follows:

T2/AAG=1.402；AAG/T3=1.779；BFL/T2=1.290；T2/AG12=1.710；

T2/T1=1.841；ALT/BFL=1.508；|f1/f|+|f3/f|=3.195；

ALT/T2=1.944；ALT/T3=4.850；ALT/AAG=2.726；

ALT/AG12=3.324；AG12/T1=1.077；AAG/T1=1.313；

T1/T3=1.355；|v1-v2|=0.402；|v1-v3|=25.526；

wherein,

t1 is the thickness of the first lens 3 on the optical axis I;

t2 is the thickness of the second lens 4 on the optical axis I;

t3 is the thickness of the third lens 5 on the optical axis I;

AG12 is an air gap on the optical axis I from the image-side surface 32 of the first lens element 3 to the object-side surface 41 of the second lens element 4;

AAG is the sum of two air gaps on the optical axis I of the first lens 3 to the third lens 5;

BFL is the distance from the image-side surface 52 of the third lens element 5 to the image plane 100 on the optical axis I;

ALT is the sum of thicknesses of the first lens 3, the second lens 4, and the third lens 5 on the optical axis I, i.e., the sum of T1, T2, and T3;

f is the focal length of the optical lens 10 as a whole;

f1 is the focal length of the first lens 3;

f3 is the focal length of the third lens 5;

v1 is the abbe number of the first lens 3;

v2 is the abbe number of the second lens 4;

v3 is the abbe number of the third lens 5;

referring to fig. 3, the diagram (a) illustrates longitudinal spherical aberration (longitudinal spherical aberration) of the first embodiment, the diagrams (b) and (c) illustrate astigmatic aberration (astigmatic aberration) of the first embodiment in sagittal direction and astigmatic aberration in meridional direction on the image plane 100, respectively, and the diagram (d) illustrates distortion aberration (distortion aberration) of the first embodiment on the image plane 100. In the longitudinal spherical aberration diagram of the first embodiment shown in fig. 3(a), the curves formed by each wavelength are very close, which means that the off-axis light rays with different heights of each wavelength are all concentrated near the imaging point, and the deviation of the imaging point of the off-axis light rays with different heights is controlled to be ± 0.05mm according to the deflection amplitude of each curve, so that the first preferred embodiment can obviously improve the spherical aberration with different wavelengths, and in addition, the three representative wavelengths are also very close to each other, which means that the imaging positions of the light rays with different wavelengths are very concentrated, thereby obviously improving the chromatic aberration.

In the two astigmatic aberration diagrams of FIGS. 3(b) and 3(c), the focal lengths of the three representative wavelengths over the entire field of view fall within + -0.05 mm, which illustrates that the optical imaging lens of the first preferred embodiment can effectively eliminate the aberrations, and in addition, the distances between the three representative wavelengths are relatively close to each other, which also significantly improves the on-axis dispersion. The distortion aberration diagram of fig. 3(d) shows that the distortion aberration of the first preferred embodiment is maintained within a range of ± 1%, which illustrates that the distortion aberration of the first preferred embodiment meets the imaging quality requirement of the optical system, and thus compared with the conventional optical lens, the first preferred embodiment can effectively overcome chromatic aberration and provide better imaging quality when the system length is shortened to be within 3.0mm, so that the first preferred embodiment can achieve the effect of shortening the lens length while maintaining good optical performance.

Referring to fig. 6, a second embodiment of the optical imaging lens system 10 of the present invention is substantially similar to the first embodiment except for the curvature radius, the lens refractive index, the lens curvature radius, the lens thickness, the aspheric surface coefficient of the lens, the back focal length, and other relevant parameters. Note here that, in fig. 6, the same reference numerals of the concave surface portion and the convex surface portion as those of the first embodiment are omitted for clarity of illustration.

The detailed optical data is shown in fig. 8, and the overall system focal length of the second embodiment is 1.5564mm, the half field angle (HFOV) is 37.451 °, the aperture value (Fno) is 2.8, and the system length is 2.9031 mm.

As shown in fig. 9, the aspheric coefficients of the object-side surface 31 of the first lens element 3 to the image-side surface 52 of the third lens element 5 in formula (1) are shown.

In addition, the relationship between the important parameters in the optical imaging lens 10 of the second embodiment is as follows:

T2/AAG=1.457；AAG/T3=1.393；BFL/T2=1.1.946；T2/AG12=1.700；

T2/T1=1.409；ALT/BFL=1.132；|f1/f|+|f3/f|=4.225；

ALT/T2=2.202；ALT/T3=4.471；ALT/AAG=3.209；

ALT/AG12=3.745；AG12/T1=0.829；AAG/T1=0.967

T1/T3=1.441；|v1-v2|=0.402；|v1-v3|=25.526。

referring to fig. 7, it can be seen from the longitudinal spherical aberration of (a), the astigmatic aberrations of (b) and (c), and the distortion aberration diagram of (d) that the second embodiment can maintain good optical performance.

Referring to fig. 10, a third embodiment of an optical imaging lens system 10 according to the present invention is substantially similar to the first embodiment, and has different relevant parameters such as curvature radius, lens refractive index, lens curvature radius, lens thickness, lens aspheric coefficient or back focal length, and the main differences between the third embodiment and the first embodiment are as follows: the image-side surface 32 of the first lens element 3 has a concave portion 321 located in the vicinity of the optical axis I and a convex portion 323 located in the vicinity of the circumference, and the object-side surface 51 of the third lens element 5 is a concave portion 51 and has a concave portion 513 located in the vicinity of the optical axis and a concave portion 512 located in the vicinity of the circumference. Note here that, in fig. 10, the same reference numerals of the concave surface portion and the convex surface portion as those of the first embodiment are omitted for clarity of illustration.

The detailed optical data is shown in fig. 12, and the overall system focal length of the third embodiment is 1.6897mm, the half field angle (HFOV) is 35.258 °, the aperture value (Fno) is 2.8, and the system length is 2.5833 mm.

As shown in fig. 13, the aspheric coefficients of the object-side surface 31 of the first lens element 3 to the image-side surface 52 of the third lens element 5 in the formula (1) are shown.

In addition, the relationship among the important parameters in the optical imaging lens 10 of the third embodiment is as follows:

T2/AAG=1.400；AAG/T3=0.900；BFL/T2=1.446；T2/AG12=1.700；

T2/T1=1.400；ALT/BFL=1.735；|f1/f|+|f3/f|=2.152；

ALT/T2=2.507；ALT/T3=3.161；ALT/AAG=3.511；

ALT/AG12=4.264；AG12/T1=0.823；AAG/T1=1.000；

T1/T3=0.901；|v1-v2|=0.000；|v1-v3|=25.526。

referring to fig. 11, it can be seen from the longitudinal spherical aberration of (a), the astigmatic aberrations of (b) and (c), and the distortion aberration diagram of (d) that the third embodiment can maintain good optical performance.

Referring to fig. 14, a fourth embodiment of the optical imaging lens assembly 10 of the present invention is substantially similar to the third embodiment, i.e., the image-side surface 32 of the first lens element 3 has a concave portion 321 located in the vicinity of the optical axis I and a convex portion 323 located in the vicinity of the circumference, and the object-side surface 51 of the third lens element 5 is a concave surface 51 and has a concave portion 513 located in the vicinity of the optical axis and a concave portion 512 located in the vicinity of the circumference. It should be noted that, for clarity of illustration, the same reference numerals for the concave and convex portions as in the first embodiment are omitted in fig. 14, except for the relevant parameters such as the curvature radius, the lens refractive index, the lens curvature radius, the lens thickness, the aspheric surface coefficient of the lens, or the back focal length.

The detailed optical data is shown in fig. 16, and the overall system focal length of the fourth embodiment is 1.6958mm, the half field angle (HFOV) is 35.166 °, the aperture value (Fno) is 2.8, and the system length is 2.7498 mm.

As shown in fig. 17, the aspheric coefficients of the object-side surface 31 of the first lens element 3 to the image-side surface 52 of the third lens element 5 in the formula (1) are shown.

In addition, the relationship among the important parameters in the optical imaging lens 10 of the fourth embodiment is as follows:

T2/AAG=1.821；AAG/T3=0.900；BFL/T2=1.111；T2/AG12=2.212；

T2/T1=1.821；ALT/BFL=1.943；|f1/f|+|f3/f|=2.093；

ALT/T2=2.159；ALT/T3=3.541；ALT/AAG=3.932；

ALT/AG12=4.775；AG12/T1=0.823；AAG/T1=1.000；

T1/T3=0.901；|v1-v2|=0.000；|v1-v3|=25.526。

referring to fig. 15, it can be seen from the longitudinal spherical aberration of (a), the astigmatic aberrations of (b) and (c), and the distortion aberration diagram of (d) that the fourth embodiment can maintain good optical performance.

Referring to fig. 18, a fifth embodiment of the optical imaging lens assembly 10 according to the present invention is designed similarly to the first embodiment, except for the relevant parameters such as the curvature radius, the lens refractive index, the lens curvature radius, the lens thickness, the aspheric coefficients of the lens element, or the back focal length, and it should be noted that the same reference numerals for the concave portion and the convex portion as those in the first embodiment are omitted in fig. 18 for clarity of illustration.

The detailed optical data is shown in fig. 20, and the overall system focal length of the fifth embodiment is 1.5527mm, the half field angle (HFOV) is 37.242 °, the aperture value (Fno) is 2.8, and the system length is 3.0775 mm.

As shown in fig. 21, the aspheric coefficients of the object-side surface 31 of the first lens element 3 to the image-side surface 52 of the third lens element 5 in the formula (1) are shown.

In addition, the relationship between the important parameters in the optical imaging lens 10 of the fifth embodiment is as follows:

T2/AAG=2.430；AAG/T3=1.327；BFL/T2=1.117；T2/AG12=2.994；

T2/T1=1.756；ALT/BFL=1.682；|f1/f|+|f3/f|=5.309；

ALT/T2=1.880；ALT/T3=6.061；ALT/AAG=4.567；

ALT/AG12=5.627；AG12/T1=0.586；AAG/T1=0.723；

T1/T3=1.837；|v1-v2|=0.402；|v1-v3|=29.065。

referring to fig. 19, it can be seen from the longitudinal spherical aberration of (a), the astigmatic aberrations of (b) and (c), and the distortion aberration diagram of (d) that the fifth embodiment can maintain good optical performance.

Referring to fig. 22, a sixth embodiment of the optical imaging lens assembly 10 of the present invention is substantially similar to the third embodiment, i.e., the image-side surface 32 of the first lens element 3 has a concave portion 321 located in the vicinity of the optical axis I and a convex portion 323 located in the vicinity of the circumference, and the object-side surface 51 of the third lens element 5 is a concave surface 51 and has a concave portion 513 located in the vicinity of the optical axis and a concave portion 512 located in the vicinity of the circumference. It should be noted that, for clarity of illustration, the same reference numerals for the concave and convex portions as in the first embodiment are omitted in fig. 22, except for the relevant parameters such as the curvature radius, the lens refractive index, the lens curvature radius, the lens thickness, the aspheric surface coefficient of the lens, or the back focal length.

The detailed optical data is shown in fig. 24, and the overall system focal length of the sixth embodiment is 1.8653mm, the half field angle (HFOV) is 32.631 °, the aperture value (Fno) is 2.8, and the system length is 3.0625 mm.

As shown in fig. 25, the aspheric coefficients of the object-side surface 31 of the first lens element 3 to the image-side surface 52 of the third lens element 5 in the formula (1) are shown.

In addition, the relationship among the important parameters in the optical imaging lens 10 of the sixth embodiment is as follows:

T2/AAG=2.193；AAG/T3=1.371；BFL/T2=1.155；T2/AG12=2.684；

T2/T1=1.424；ALT/BFL=1.762；|f1/f|+|f3/f|=1.919；

ALT/T2=2.035；ALT/T3=6.118；ALT/AAG=4.463；

ALT/AG12=5.461；AG12/T1=0.531；AAG/T1=0.649；

T1/T3=2.112；|v1-v2|=0.000；|v1-v3|=25.526。

referring to fig. 23, it can be seen from the longitudinal spherical aberration of (a), the astigmatic aberrations of (b) and (c), and the distortion aberration diagram of (d) that the sixth embodiment can maintain good optical performance.

Referring to fig. 26, a table diagram of the optical parameters of the six preferred embodiments shows that the relational expression between the optical parameters of the optical imaging lens 10 of the present invention indeed satisfies the conditional expressions, and the optical performance still has better performance when the system length is shortened, so that the present invention can be applied to a portable electronic device to manufacture a thinner product.

In summary, the optical imaging lens 10 of the present invention can achieve the following effects and advantages, so as to achieve the objectives of the present invention:

first, the object side surface 31 of the first lens element 3 is a convex surface, and has a convex surface portion 311 located in the vicinity of the optical axis I and a convex surface portion 312 located in the vicinity of the circumference, and the second lens element 4 is a lens element with positive refractive power. The object-side surface 41 of the second lens element 4 is concave and has a concave portion 411 located in the vicinity of the optical axis I and a concave portion 412 located in the vicinity of the circumference, and the image-side surface 42 of the second lens element 4 is convex and has a convex portion 421 located in the vicinity of the optical axis I and a convex portion 422 located in the vicinity of the circumference. The third lens element 5 with negative refractive index has a convex surface 512 on the object-side surface 51 of the third lens element 5 in a region around the circumference, and the image-side surface 52 of the third lens element 5 has a concave surface 521 on the region around the optical axis I and a convex surface 522 on the region around the circumference. The object-side surface of the first lens element is convex to assist in collecting imaging light, the object-side surface of the second lens element is concave, the image-side surface of the second lens element is convex, the concave surface of the third lens element is in the vicinity of the object-side surface, the concave surface of the image-side surface is in the vicinity of the optical axis, and the convex surface of the periphery is in the vicinity of the optical axis.

The positive refractive index of the second lens element can provide the refractive index required by the whole lens system, the positive refractive index of the first lens element can assist in sharing the positive refractive index required by the whole lens system, thereby reducing the difficulty in designing and manufacturing the whole lens system, and the negative refractive index of the third lens element has the effect of correcting aberration; in addition, the aperture is arranged between the first lens and the second lens to help improve the imaging quality.

In addition, through the above six embodiments, the design of the optical imaging lens 10 of the present invention is shown, and the numerical control of each parameter of the embodiments meets the above conditional expressions, which can assist the designer to design a lens with good optical performance, and the system length of the embodiments can be shortened to be less than 3.1mm, compared with the existing optical imaging lens, the lens of the present invention can be used to manufacture thinner products, so that the present invention has economic benefits meeting the market requirements.

Referring to fig. 27, in a first embodiment of the electronic device 1 applying the optical imaging lens 10, the electronic device 1 includes a housing 11 and an image module 12 installed in the housing 11. The electronic device 1 is described herein by way of example only as a mobile phone, but the type of the electronic device 1 is not limited thereto. For example, electronic devices may also include, but are not limited to, cameras, tablet computers, Personal Digital Assistants (PDAs), and the like.

The image module 12 includes the optical imaging lens 10, a lens barrel 21 for disposing the optical imaging lens 10, a module rear seat unit 120 for disposing the lens barrel 21, a substrate (not shown) for disposing the module rear seat unit, and an image sensor 130 disposed on the substrate and located at the image side of the optical imaging lens 10. The image plane 100 (see fig. 2) is formed on the image sensor 130.

The module rear seat unit 120 has a lens rear seat 121 and an image sensor rear seat 122 disposed between the lens rear seat 121 and the image sensor 130. The lens barrel 21 and the lens backseat 121 are coaxially disposed along an axis ii, and the lens barrel 21 is disposed inside the lens backseat 121.

It should be noted that although the filter 6 is shown in the embodiment, the structure of the filter 6 may be omitted in other embodiments, and the need of the filter 6 is not limited, and the housing, the lens barrel, and/or the module rear seat unit may be a single component or a plurality of components, and need not be limited thereto; next, the image sensor used in this embodiment is directly connected to the substrate in a Chip On Board (COB) package, and the difference between the chip on board package and the conventional Chip Scale Package (CSP) package is that the CSP package does not need a cover glass (cover glass), so that the cover glass does not need to be disposed in front of the image sensor in the optical imaging lens, but the invention is not limited thereto.

Referring to fig. 28, a second embodiment of an electronic device 1 applying the optical imaging lens 10 is shown, and the main differences between the second embodiment and the electronic device 1 of the first embodiment are: the module backseat unit 120 is of a Voice Coil Motor (VCM) type. The lens rear seat 121 has a first seat 123, a second seat 124, a coil 125 and a magnetic assembly 126. The first base 123 is for the lens barrel 21 to be disposed, and is attached to the outer side of the lens barrel 21 and disposed along the axis III, and the second base 124 is disposed along the axis III and around the outer side of the first base 123. The coil 125 is disposed between the outer side of the first seat 123 and the inner side of the second seat 124. The magnetic assembly 126 is disposed between the outer side of the coil 125 and the inner side of the second base 124. The first base 123 can move along the axis III with the lens barrel 21 and the optical imaging lens disposed in the lens barrel 21. The image sensor rear base 122 is attached to the second base 124. The filter 6 is disposed on the image sensor rear seat 122.

Other component structures of the second embodiment of the electronic device 1 are similar to those of the electronic device 1 of the first embodiment, and are not described herein again.

By installing the optical imaging lens 10, since the system length of the optical imaging lens 10 can be effectively shortened, the thicknesses of the first embodiment and the second embodiment of the electronic device 1 can be relatively reduced, so as to manufacture thinner products, and good optical performance and imaging quality can still be provided, so that the electronic device 1 of the invention not only has the economic benefit of reducing the consumption of the shell raw materials, but also can meet the design trend and consumption requirements of light, thin and short products.

While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (17)

1. An optical imaging lens characterized in that: the image sensor sequentially comprises, along an optical axis from an object side to an image side:

the first lens element with positive refractive power has a convex object-side surface, a convex part in the area near the optical axis and a convex part in the area near the circumference;

an aperture;

a second lens element with positive refractive power having a concave object-side surface, a concave portion on the object-side surface of the second lens element and a convex portion on the image-side surface of the second lens element, wherein the concave portion is located in a region near the optical axis; and

a third lens element with negative refractive power having a concave portion on an object-side surface and a concave portion on an image-side surface, and a convex portion on an image-side surface;

wherein the optical imaging lens only has the three lenses with refractive indexes, and satisfies the following conditional expression:

1.4≤T2/AAG,ALT/BFL≤2.0,ALT/T2≤2.65；

wherein T2 represents the thickness of the second lens element on the optical axis, AAG represents the sum of the widths of two air gaps between the first to third lens elements on the optical axis, ALT represents the sum of the thicknesses of the three lens elements on the optical axis, and BFL represents the back focal length of the optical imaging lens, i.e., the distance between the image-side surface of the third lens element and the image-forming surface on the optical axis.

2. An optical imaging lens according to claim 1, characterized in that: the optical imaging lens meets the following conditional expression:

0.9≤AAG/T3；

where T3 denotes the thickness of the third lens on the optical axis.

3. An optical imaging lens according to claim 2, characterized in that: the optical imaging lens meets the following conditional expression:

1.7≤T2/AG12；

where AG12 denotes an air gap width on the optical axis between the first lens and the second lens.

4. An optical imaging lens according to claim 1, characterized in that: the optical imaging lens meets the following conditional expression:

1.9≤|f1/f|+|f3/f|；

where f1 denotes the first lens focal length, f3 denotes the third lens focal length, and f denotes the focal length of the optical lens as a whole.

5. An optical imaging lens according to claim 1, characterized in that: the optical imaging lens meets the following conditional expression:

1.1≤BFL/T2。

6. an optical imaging lens according to claim 5, characterized in that: the optical imaging lens meets the following conditional expression:

4.0≤ALT/T3；

where T3 denotes the thickness of the third lens on the optical axis.

7. An optical imaging lens according to claim 5, characterized in that: the optical imaging lens meets the following conditional expression:

2.7≤ALT/AAG≤7.0。

8. an optical imaging lens according to claim 5, characterized in that: the optical imaging lens meets the following conditional expression:

|v1-v2|≤10.0；

where v1 denotes the abbe number of the first lens, and v2 denotes the abbe number of the second lens.

9. An optical imaging lens according to claim 5, characterized in that: the third lens has a convex surface portion located in a region near the optical axis.

10. An optical imaging lens according to claim 1, characterized in that: the optical imaging lens meets the following conditional expression:

1.7≤T2/AG12；

where AG12 denotes an air gap width on the optical axis between the first lens and the second lens.

11. An optical imaging lens according to claim 10, characterized in that: the optical imaging lens meets the following conditional expression:

20.0≤|v1-v3|≤50.0；

where v1 denotes the abbe number of the first lens, and v3 denotes the abbe number of the third lens.

12. An optical imaging lens according to claim 10, characterized in that: the optical imaging lens meets the following conditional expression:

0.5≤AG12/T1；

where T1 denotes the thickness of the first lens on the optical axis.

13. An optical imaging lens according to claim 10, characterized in that: the optical imaging lens meets the following conditional expression:

0.6≤AAG/T1；

where T1 denotes the thickness of the first lens on the optical axis.

14. An optical imaging lens according to claim 10, characterized in that: the optical imaging lens meets the following conditional expression:

1.3≤T1/T3；

where T1 denotes a thickness of the first lens on the optical axis, and T3 denotes a thickness of the third lens on the optical axis.

15. An optical imaging lens according to claim 1, characterized in that: the optical imaging lens meets the following conditional expression:

1.4≤T2/T1；

where T1 denotes the thickness of the first lens on the optical axis.

16. An optical imaging lens according to claim 1, characterized in that: the optical imaging lens meets the following conditional expression:

3.3≤ALT/AG12≤10.0；

where AG12 denotes an air gap width on the optical axis between the first lens and the second lens.

17. An electronic device, characterized in that: a housing; and an image module, which is installed in the housing and includes an optical imaging lens according to any one of claims 1 to 16, a lens barrel for the optical imaging lens, a module rear seat unit for the lens barrel, a substrate for the module rear seat unit, and an image sensor disposed on the substrate and located on an image side of the optical imaging lens.