CN110824672A

CN110824672A - Image capturing lens system and image capturing device

Info

Publication number: CN110824672A
Application number: CN201911182041.6A
Authority: CN
Inventors: 林振诚; 薛钧哲; 陈纬彧
Original assignee: Largan Precision Co Ltd
Current assignee: Largan Precision Co Ltd
Priority date: 2016-01-21
Filing date: 2016-01-21
Publication date: 2020-02-21
Anticipated expiration: 2036-01-21
Also published as: CN110824672B; CN106990503A; CN106990503B

Abstract

The invention discloses an image capturing lens system and an image capturing device. The image capturing lens system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with negative refractive power has an object-side surface being concave at a paraxial region thereof and including at least one convex surface at an off-axis region thereof. The fourth lens element with positive refractive power. The fifth lens element with negative refractive power. The image-side surface of the sixth lens element is concave at the paraxial region and includes at least one convex surface at the off-axis region, wherein the object-side surface and the image-side surface of the sixth lens element are aspheric. When satisfying specific conditions, the device can satisfy the requirements of wide viewing angle and miniaturization. The invention also discloses an image taking device with the image taking lens system.

Description

Image capturing lens system and image capturing device

The present application is a divisional application of patent applications with application date of 2016, 21/01, application number of 201610040387.2, entitled "image capturing lens system, image capturing device and electronic device".

Technical Field

The present invention relates to an image capturing lens system and an image capturing device, and more particularly, to an image capturing lens system and an image capturing device applied to an electronic device with a compact size and a wide viewing angle.

Background

In recent years, electronic products are being thinned, and therefore the associated image capturing device is also required to be miniaturized, however, although the conventional image capturing lens system can provide a miniaturized design, it is difficult to meet the requirements of both large viewing angle and short overall length, and thus it is difficult to mount the lens system on a thin and light electronic device (such as a mobile phone, a portable device, a personal video recorder, an optical recognition device or other electronic equipment) requiring a large viewing angle.

Disclosure of Invention

The invention provides an image capturing lens system and an image capturing device, wherein the configuration that a first lens has negative refractive power in the image capturing lens system is beneficial to light rays with a larger visual angle to enter the image capturing lens system, and the light rays can be converged on an image forming surface through a fourth lens having positive refractive power and a fifth lens having negative refractive power, so that the requirements of shortening the back focal length and realizing miniaturization are met. Furthermore, the image capturing device including the image capturing lens system can achieve both wide viewing angle and miniaturization, thereby achieving better aberration control and sufficient relative illumination, and easily obtaining a configuration with a more suitable lens shape.

The present invention provides an image capturing lens system, which comprises, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with negative refractive power has an object-side surface being concave at a paraxial region thereof and including at least one convex surface at an off-axis region thereof. The fourth lens element with positive refractive power. The fifth lens element with negative refractive power. The image-side surface of the sixth lens element is concave at the paraxial region and includes at least one convex surface at the off-axis region, wherein the object-side surface and the image-side surface of the sixth lens element are aspheric. The lens in the image capturing lens system is six, at least three lenses are made of plastic materials, and an air space is arranged between any two adjacent lenses in the image capturing lens system on an optical axis. The optical axis distance between the first lens element and the second lens element is T12, the optical axis distance between the fifth lens element and the sixth lens element is T56, the focal length of the first lens element is f1, the focal length of the second lens element is f2, and the focal length of the fifth lens element is f5, which satisfy the following conditions:

1.10<T56/T12；

l f1/f2 l < 2.0; and

|f5/f2|<1.50。

the present invention further provides an image capturing device, comprising the image capturing lens system as described in the previous paragraph and an electronic photosensitive element, wherein the electronic photosensitive element is disposed on an image plane of the image capturing lens system.

The present invention provides an image capturing lens system, which comprises, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element has negative refractive power. The fourth lens element with positive refractive power. The fifth lens element with negative refractive power. The image-side surface of the sixth lens element is concave at the paraxial region and includes at least one convex surface at the off-axis region, wherein the object-side surface and the image-side surface of the sixth lens element are aspheric. The lens in the image capturing lens system is six, at least three lenses are made of plastic materials, and an air space is arranged between any two adjacent lenses in the image capturing lens system on an optical axis. The optical axis distance between the first lens and the second lens is T12, the optical axis distance between the fifth lens and the sixth lens is T56, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the fifth lens is f5, the abbe number of the first lens is V1, the abbe number of the second lens is V2, the abbe number of the third lens is V3, the abbe number of the fourth lens is V4, the abbe number of the fifth lens is V5, and the abbe number of the sixth lens is V6, which satisfies the following conditions:

1.10<T56/T12；

|f1/f2|<2.0；

l f5/f2 l < 1.50; and

1.90<(V1+V3+V4)/(V2+V5+V6)<3.5。

When T56/T12 satisfies the above condition, it is possible to have a tighter fit between the first lens and the second lens, or to avoid the need for additional components during assembly due to too long distance between the first lens and the second lens, thereby facilitating the simplification of assembly and miniaturization, and further enabling the fifth lens and the sixth lens to have more sufficient space to be configured into a shape suitable for correcting aberration.

When the | f1/f2| satisfies the above condition, it is beneficial to alleviate the refraction degree when the light enters the image capturing lens system, and avoid the noise caused by surface reflection due to too intense refraction of the light.

When the | f5/f2| satisfies the above condition, the refractive power configurations of the second lens element and the fifth lens element are properly adjusted to avoid over-correction of the aberration of the rear group lens element caused by too strong refractive power of the second lens element.

When (V1+ V3+ V4)/(V2+ V5+ V6) satisfies the above-described condition, it is possible to ensure a state in which chromatic aberration of an image is well balanced among various aberrations.

Drawings

Fig. 1 is a schematic view illustrating an image capturing apparatus according to a first embodiment of the invention;

FIG. 2 is a graph showing the spherical aberration, astigmatism and distortion of the first embodiment in order from left to right;

FIG. 3 is a schematic view illustrating an image capturing device according to a second embodiment of the present invention;

FIG. 4 is a graph showing the spherical aberration, astigmatism and distortion of the second embodiment in order from left to right;

FIG. 5 is a schematic view illustrating an image capturing apparatus according to a third embodiment of the present invention;

FIG. 6 is a graph showing the spherical aberration, astigmatism and distortion of the third embodiment in order from left to right;

FIG. 7 is a schematic view illustrating an image capturing apparatus according to a fourth embodiment of the present invention;

FIG. 8 is a graph showing the spherical aberration, astigmatism and distortion of the fourth embodiment in order from left to right;

fig. 9 is a schematic view illustrating an image capturing apparatus according to a fifth embodiment of the invention;

FIG. 10 is a graph showing the spherical aberration, astigmatism and distortion of the fifth embodiment in order from left to right;

fig. 11 is a schematic view illustrating an image capturing apparatus according to a sixth embodiment of the invention;

FIG. 12 is a graph showing spherical aberration, astigmatism and distortion curves of the sixth embodiment, in order from left to right;

fig. 13 is a schematic view illustrating an image capturing apparatus according to a seventh embodiment of the invention;

FIG. 14 is a graph showing the spherical aberration, astigmatism and distortion of the seventh embodiment in order from left to right;

fig. 15 is a schematic view illustrating an image capturing apparatus according to an eighth embodiment of the present invention;

FIG. 16 is a graph showing the spherical aberration, astigmatism and distortion of the eighth embodiment in order from left to right;

FIG. 17 is a schematic view of an electronic device according to a ninth embodiment of the invention;

FIG. 18 is a schematic view of an electronic device according to a tenth embodiment of the invention; and

fig. 19 is a schematic view illustrating an electronic device according to an eleventh embodiment of the invention.

[ notation ] to show

An electronic device: 10. 20, 30

An image taking device: 11. 21, 31

Aperture: 100. 200, 300, 400, 500, 600, 700, 800

A first lens: 110. 210, 310, 410, 510, 610, 710, 810

An object-side surface: 111. 211, 311, 411, 511, 611, 711, 811

Image-side surface: 112. 212, 312, 412, 512, 612, 712, 812

A second lens: 120. 220, 320, 420, 520, 620, 720, 820

An object-side surface: 121. 221, 321, 421, 521, 621, 721, 821

Image-side surface: 122. 222, 322, 422, 522, 622, 722, 822

A third lens: 130. 230, 330, 430, 530, 630, 730, 830

An object-side surface: 131. 231, 331, 431, 531, 631, 731, 831

Image-side surface: 132. 232, 332, 432, 532, 632, 732, 832

A fourth lens: 140. 240, 340, 440, 540, 640, 740, 840

An object-side surface: 141. 241, 341, 441, 541, 641, 741, 841

Image-side surface: 142. 242, 342, 442, 542, 642, 742, 842

A fifth lens: 150. 250, 350, 450, 550, 650, 750, 850

An object-side surface: 151. 251, 351, 451, 551, 651, 751, 851

Image-side surface: 152. 252, 352, 452, 552, 652, 752, 852

A sixth lens: 160. 260, 360, 460, 560, 660, 760, 860

An object-side surface: 161. 261, 361, 461, 561, 661, 761, 861

Image-side surface: 162. 262, 362, 462, 562, 662, 762, 862

Infrared ray filtering filter element: 170. 270, 370, 470, 570, 670, 770, 870

Imaging surface: 180. 280, 380, 480, 580, 680, 780, 880

An electron-sensitive element: 190. 290, 390, 490, 590, 690, 790, 890

f: focal length of image taking lens system

Fno: aperture value of image capturing lens system

HFOV: half of maximum visual angle in image taking lens system

V1: abbe number of first lens

V2: abbe number of second lens

V3: abbe number of third lens

V4: abbe number of fourth lens

V5: abbe number of fifth lens

V6: abbe number of sixth lens

CT 1: thickness of the first lens on the optical axis

CT 2: thickness of the second lens on the optical axis

CT 3: thickness of the third lens on the optical axis

CT 5: thickness of the fifth lens element on the optical axis

CT 6: thickness of the sixth lens element on the optical axis

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

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

T34: the distance between the third lens and the fourth lens on the optical axis

T45: the distance between the fourth lens and the fifth lens on the optical axis

T56: the distance between the fifth lens and the sixth lens on the optical axis

Y62: maximum effective radius of image-side surface of sixth lens

R3: radius of curvature of object-side surface of second lens

R4: radius of curvature of image-side surface of second lens

f 1: focal length of the first lens

f 2: focal length of the second lens

f 3: focal length of the third lens

f 4: focal length of the fourth lens

f 5: focal length of fifth lens

f 6: focal length of sixth lens

Detailed Description

An image capturing lens system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element, wherein the total number of the lens elements in the image capturing lens system is six, and at least three of the lens elements are made of plastic material.

Any two adjacent lenses of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens of the taking lens system in the front section have an air space on the optical axis; that is, the taking lens system has six single non-cemented lenses. Since the process of bonding the lens is more complicated than that of non-bonding lens, especially the bonding surface of the two lenses needs to have a curved surface with high accuracy so as to achieve high degree of adhesion when the two lenses are bonded, and the poor degree of adhesion caused by deviation may occur during the bonding process, which affects the overall optical imaging quality. Therefore, in the image capturing lens system of the present invention, an air space is formed between any two adjacent lenses on the optical axis, which can effectively improve the problem caused by lens adhesion.

The first lens element with negative refractive power has an object-side surface that is concave at a paraxial region and an image-side surface that is concave at a paraxial region, wherein the object-side surface of the first lens element can include at least one convex surface in an off-axis region. Therefore, the light with a larger visual angle can enter the image taking lens system, so that a wider visual angle can be provided.

The third lens element with positive refractive power can effectively correct the aberration generated by the first lens element.

The fourth lens element with positive refractive power can provide the main positive refractive power for the image capturing lens system, thereby effectively shortening the total track length thereof.

The fifth lens element with negative refractive power has an object-side surface being concave at a paraxial region thereof and an image-side surface being convex at a paraxial region thereof, wherein the image-side surface of the fifth lens element can include at least one concave surface at an off-axis region thereof. The incident light is focused on the imaging surface by the negative refractive power of the fifth lens element and the positive refractive power of the fourth lens element, so that the requirements of shortening the back focal length and miniaturization can be met.

The sixth lens element with negative refractive power has an object-side surface being convex at a paraxial region and an image-side surface being concave at a paraxial region, wherein the image-side surface of the sixth lens element comprises at least one convex surface at an off-axis region. Therefore, the Principal Point (Principal Point) of the image taking lens system can be far away from the imaging surface, the back focal length of the image taking lens system can be favorably shortened to maintain miniaturization, the incident angle of off-axis field light can be effectively suppressed, and the response efficiency of the electronic photosensitive element is improved.

The distance between the first lens element and the second lens element is T12, and the distance between the fifth lens element and the sixth lens element is T56, which satisfies the following conditions: 1.10< T56/T12. Therefore, the first lens and the second lens are matched closely, or extra elements are not needed when the first lens and the second lens are assembled due to too far distance between the first lens and the second lens, so that the assembly and the miniaturization are facilitated, and the fifth lens and the sixth lens have more enough space and can be configured into shapes which are more suitable for correcting aberration. Preferably, the following conditions are satisfied: 1.25< T56/T12< 4.0. More preferably, the following conditions may be satisfied: 1.40< T56/T12< 3.0.

The focal length of the first lens is f1, the focal length of the second lens is f2, and the following conditions are satisfied: i f1/f 2I < 2.0. Therefore, the refraction degree of the light entering the image taking lens system is favorably alleviated, and the noise caused by surface reflection and the like due to severe light refraction can be avoided. Preferably, the following conditions are satisfied: i f1/f 2I < 1.0. More preferably, the following conditions may be satisfied: i f1/f 2I < 0.50.

The focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following conditions are satisfied: i f5/f 2I < 1.50. By properly adjusting the refractive power configurations of the second lens element and the fifth lens element, excessive aberration correction of the rear group lens element due to too strong refractive power of the second lens element can be avoided. Preferably, the following conditions are satisfied: i f5/f 2I < 1.0. More preferably, the following conditions may be satisfied: i f5/f 2I < 0.50.

The image capturing lens system may further include an aperture stop disposed between the first lens element and the third lens element, wherein the aperture stop of the image capturing lens system is Fno, which satisfies the following condition: fno is more than 1.6 and less than or equal to 2.65. Therefore, the balance between the brightness of the imaging surface and the imaging focal depth is facilitated, and the sufficient brightness and the imaging quality are ensured.

The focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the focal length of the sixth lens is f6, wherein in | f1|, | f2|, | f3|, | f4|, | f5|, and | f6|, | f4| is the minimum value. Therefore, the lens with main positive refractive power in the image capturing lens system can be configured to be closer to the imaging surface, so that the sensitivity of the whole image capturing lens system to the lens with positive refractive power can be reduced.

The focal length of the image capturing lens system is f, the focal length of the third lens element is f3, and the focal length of the fourth lens element is f4, which satisfy the following conditions: 1.5< | f/f3| + | f/f4| < 3.0. Therefore, the third lens element and the fourth lens element can share the positive refractive power of the image capturing lens system, and the problem of the sensitivity of the lens elements is further reduced, thereby improving the manufacturing yield.

The optical axis thickness of the fifth lens element is CT5, the optical axis thickness of the sixth lens element is CT6, and the distance between the fifth lens element and the sixth lens element is T56, which satisfies the following conditions: 0.85< T56/(CT5+ CT6) < 2.0. Therefore, the fifth lens and the sixth lens can further show better shapes and configurations, and the imaging quality is improved.

The optical axis distance between the first lens element and the second lens element is T12, the optical axis distance between the second lens element and the third lens element is T23, the optical axis distance between the third lens element and the fourth lens element is T34, the optical axis distance between the fourth lens element and the fifth lens element is T45, and the optical axis distance between the fifth lens element and the sixth lens element is T56, which satisfies the following conditions: 2.5< (T12+ T56)/(T23+ T34+ T45) < 25. Therefore, the lenses can be matched closely, and the sensitivity to manufacturing tolerance, temperature effect and the like can be reduced.

An abbe number of the first lens is V1, an abbe number of the second lens is V2, an abbe number of the third lens is V3, an abbe number of the fourth lens is V4, an abbe number of the fifth lens is V5, and an abbe number of the sixth lens is V6, which satisfy the following conditions: 1.90< (V1+ V3+ V4)/(V2+ V5+ V6) < 3.5. Therefore, the image chromatic aberration can be ensured to be in a more balanced state in various aberrations.

The thickness of the first lens element along the optical axis is CT1, and the thickness of the third lens element along the optical axis is CT3, which satisfies the following conditions: 0.70< CT1/CT3< 1.5. Therefore, the problems of difficulty in molding or assembling, insufficient structural strength of the first lens and the like caused by the fact that the first lens is too thin can be avoided.

The thickness of the first lens element along the optical axis is CT1, and the thickness of the second lens element along the optical axis is CT2, which satisfies the following conditions: 0.10< CT2/CT1< 0.70. Therefore, the aberration generated by the first lens can be further adjusted and the sensitivity of the first lens can be reduced.

The imaging lens system has a focal length f, a radius of curvature of the object-side surface of the second lens element is R3, and a radius of curvature of the image-side surface of the second lens element is R4, which satisfy the following conditions: i f/R3| + | f/R4| < 1.0. Therefore, the change of the second lens surface shape is favorably slowed down, and the problem of forming is reduced.

The focal length of the image capturing lens system is f, and the maximum effective radius of the image-side surface of the sixth lens element is Y62, which satisfies the following conditions: 0.90< Y62/f < 1.30. Therefore, the visual angle can be expanded, the configuration of the short back focal length can be matched easily, and the miniaturization of the image taking lens system is facilitated.

In the image capturing lens system provided by the invention, the lens can be made of plastic or glass. When the lens is made of plastic, the production cost can be effectively reduced. In addition, when the lens element is made of glass, the degree of freedom of the refractive power configuration of the image capturing lens system can be increased. In addition, the object side surface and the image side surface of the image capturing lens system can be Aspheric Surfaces (ASP), which can be easily made into shapes other than spherical surfaces to obtain more control variables for reducing aberration and further reducing the number of lenses, thereby effectively reducing the total length of the image capturing lens system.

In addition, in the imaging lens system provided by the invention, if the lens surface is a convex surface and the position of the convex surface is not defined, it means that the lens surface can be a convex surface at a position close to the optical axis; if the lens surface is concave and the concave position is not defined, it means that the lens surface can be concave at the paraxial region. In the image capturing lens system provided by the present invention, if the lens element has positive refractive power or negative refractive power, or the focal length of the lens element, the refractive power or the focal length of the lens element at the paraxial region thereof can be referred to.

In addition, in the image capturing lens system of the invention, at least one diaphragm can be arranged according to requirements to reduce stray light, which is beneficial to improving the image quality.

The image plane of the image capturing lens system of the present invention may be a plane or a curved surface with any curvature, especially a curved surface with a concave surface facing the object side, depending on the difference of the corresponding electronic photosensitive elements.

In the image capturing lens system of the present invention, the aperture configuration may be a front aperture, i.e. the aperture is disposed between the object and the first lens element, or a middle aperture, i.e. the aperture is disposed between the first lens element and the image plane. If the aperture is a front aperture, a longer distance can be generated between the Exit Pupil (Exit Pupil) of the image capturing lens system and the imaging surface, so that the image capturing lens system has a Telecentric (telecentricity) effect, and the image receiving efficiency of a CCD (charge coupled device) or a CMOS (complementary metal oxide semiconductor) of the electronic photosensitive element can be increased; if the aperture is a central aperture, it is helpful to enlarge the field angle of the system, so that the image capturing lens system has the advantage of a wide-angle lens.

The image capturing lens system of the invention can also be applied to electronic devices such as three-dimensional (3D) image capturing, digital cameras, mobile products, digital flat panels, smart televisions, network monitoring equipment, motion sensing game machines, automobile data recorders, backing developing devices, wearable products and the like in many aspects.

The invention provides an image capturing device, which comprises the image capturing lens system and an electronic photosensitive element, wherein the electronic photosensitive element is arranged on an imaging surface of the image capturing lens system. The configuration of the first lens element with negative refractive power in the image capturing lens system is helpful for light rays with a larger viewing angle to enter the image capturing lens system, and the fourth lens element with positive refractive power and the fifth lens element with negative refractive power can focus the light rays on an image forming surface, so that the requirements of shortening the back focal length and miniaturization are met. Therefore, the image capturing device with wide view angle and miniaturization can realize better aberration control and sufficient relative illumination, and the configuration with more suitable lens shape is easier to obtain. Preferably, the image capturing device may further include a lens Barrel (Barrel Member), a support device (HolderMember), or a combination thereof.

The invention provides an electronic device comprising the image capturing device. Therefore, the imaging quality is improved. Preferably, the electronic device may further include a control unit, a display unit, a storage unit, a temporary storage unit (RAM), or a combination thereof.

The following provides a detailed description of the embodiments with reference to the accompanying drawings.

< first embodiment >

Referring to fig. 1 and fig. 2, wherein fig. 1 is a schematic diagram of an image capturing device according to a first embodiment of the invention, and fig. 2 is a graph of spherical aberration, astigmatism and distortion of the first embodiment in order from left to right. As shown in fig. 1, the image capturing device of the first embodiment includes an image capturing lens system (not shown) and an electronic photosensitive element 190. The image capturing lens system sequentially includes, from an object side to an image side, a first lens element 110, an aperture 100, a second lens element 120, a third lens element 130, a fourth lens element 140, a fifth lens element 150, a sixth lens element 160, an ir-cut filter element 170, and an image plane 180, and the electronic sensing element 190 is disposed on the image plane 180 of the image capturing lens system, wherein the number of the lens elements in the image capturing lens system is six (110 and 160), and an air space is disposed between any two adjacent lens elements in the image capturing lens system on an optical axis.

The first lens element 110 with negative refractive power has an object-side surface 111 being concave in a paraxial region thereof and an image-side surface 112 being concave in a paraxial region thereof. In addition, the object-side surface 111 of the first lens element includes at least one convex surface at an off-axis position.

The second lens element 120 with negative refractive power has a convex object-side surface 121 and a concave image-side surface 122.

The third lens element 130 with positive refractive power has a convex object-side surface 131 and a convex image-side surface 132.

The fourth lens element 140 with positive refractive power has a convex object-side surface 141 and a convex image-side surface 142.

The fifth lens element 150 with negative refractive power has an object-side surface 151 being concave in a paraxial region thereof and an image-side surface 152 being convex in a paraxial region thereof. In addition, the image-side surface 152 of the fifth lens element includes at least one concave surface on the off-axis side.

The sixth lens element 160 with negative refractive power has an object-side surface 161 being convex in a paraxial region thereof and an image-side surface 162 being concave in a paraxial region thereof. In addition, the sixth lens element has an image-side surface 162 with at least one convex surface in an off-axis direction.

The ir-cut filter 170 is made of glass, and is disposed between the sixth lens element 160 and the image plane 180 without affecting the focal length of the image capturing lens system.

The curve equation of the aspherical surface of each lens described above is as follows:

wherein:

x: the distance between the point on the aspheric surface, which is Y from the optical axis, and the relative distance between the point and the tangent plane of the intersection point tangent to the aspheric surface optical axis;

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

r: a radius of curvature;

k: the cone coefficient; and

ai: the ith order aspheric coefficients.

In the image capturing lens system of the first embodiment, the focal length of the image capturing lens system is f, the aperture value (f-number) of the image capturing lens system is Fno, and half of the maximum viewing angle in the image capturing lens system is HFOV, and the values thereof are as follows: f is 1.94 mm; fno 2.52; and HFOV 59.5 degrees.

In the taking lens system of the first embodiment, the abbe number of the first lens element 110 is V1, the abbe number of the second lens element 120 is V2, the abbe number of the third lens element 130 is V3, the abbe number of the fourth lens element 140 is V4, the abbe number of the fifth lens element 150 is V5, and the abbe number of the sixth lens element 160 is V6, which satisfy the following conditions: (V1+ V3+ V4)/(V2+ V5+ V6) 2.07.

In the image capturing lens system of the first embodiment, the thickness of the first lens element 110 on the optical axis is CT1, the thickness of the second lens element 120 on the optical axis is CT2, and the thickness of the third lens element 130 on the optical axis is CT3, which satisfy the following conditions: CT1/CT3 is 0.86; and CT2/CT1 is 0.43.

In the image capturing lens system of the first embodiment, an axial distance between the first lens element 110 and the second lens element 120 is T12, an axial distance between the second lens element 120 and the third lens element 130 is T23, an axial distance between the third lens element 130 and the fourth lens element 140 is T34, an axial distance between the fourth lens element 140 and the fifth lens element 150 is T45, and an axial distance between the fifth lens element 150 and the sixth lens element 160 is T56, which satisfy the following conditions: (T12+ T56)/(T23+ T34+ T45) ═ 3.17; and T56/T12 ═ 1.66.

In the image capturing lens system of the first embodiment, the thickness of the fifth lens element 150 on the optical axis is CT5, the thickness of the sixth lens element 160 on the optical axis is CT6, and the distance between the fifth lens element 150 and the sixth lens element 160 on the optical axis is T56, which satisfies the following conditions: T56/(CT5+ CT6) is 0.75.

In the taking lens system of the first embodiment, the maximum effective radius of the image-side surface 162 of the sixth lens element is Y62, and the focal length of the taking lens system is f, which satisfies the following conditions: y62/f is 1.06.

In the image capturing lens system of the first embodiment, a focal length of the image capturing lens system is f, a radius of curvature of the object-side surface 121 of the second lens element is R3, and a radius of curvature of the image-side surface 122 of the second lens element is R4, which satisfy the following conditions: i f/R3| + | f/R4| -0.81.

In the taking lens system of the first embodiment, the focal length of the first lens element 110 is f1, and the focal length of the second lens element 120 is f2, which satisfies the following conditions: i f1/f2 i 0.112.

In the taking lens system of the first embodiment, the focal length of the second lens element 120 is f2, and the focal length of the fifth lens element 150 is f5, which satisfies the following conditions: i f5/f2 i 0.083.

In the image capturing lens system of the first embodiment, the focal length of the image capturing lens system is f, the focal length of the third lens element 130 is f3, and the focal length of the fourth lens element 140 is f4, which satisfies the following conditions: i f/f3| + | f/f4| -2.30.

In the image capturing lens system of the first embodiment, the focal length of the first lens element 110 is f1, the focal length of the second lens element 120 is f2, the focal length of the third lens element 130 is f3, the focal length of the fourth lens element 140 is f4, the focal length of the fifth lens element 150 is f5, and the focal length of the sixth lens element 160 is f6, where | f4| is the minimum value among | f1|, | f2|, | f3|, | f4|, | f5|, and | f6 |.

The following list I and list II are referred to cooperatively.

In table one, the detailed structural data of the first embodiment of fig. 1 are shown, wherein the units of the radius of curvature, the thickness and the focal length are mm, and the surfaces 0-16 sequentially represent the surfaces from the object side to the image side. Table II shows aspheric data of the first embodiment, where k represents the cone coefficients in the aspheric curve equation, and A4-A16 represents the 4 th to 16 th order aspheric coefficients of each surface. In addition, the following tables of the embodiments correspond to the schematic diagrams and aberration graphs of the embodiments, and the definitions of the data in the tables are the same as those of the first and second tables of the first embodiment, which is not repeated herein.

< second embodiment >

Referring to fig. 3 and fig. 4, wherein fig. 3 is a schematic diagram of an image capturing device according to a second embodiment of the invention, and fig. 4 is a graph of spherical aberration, astigmatism and distortion of the second embodiment in order from left to right. As shown in fig. 3, the image capturing device of the second embodiment includes an image capturing lens system (not shown) and an electronic photosensitive element 290. The image capturing lens system includes, in order from an object side to an image side, a first lens element 210, a second lens element 220, an aperture stop 200, a third lens element 230, a fourth lens element 240, a fifth lens element 250, a sixth lens element 260, an ir-cut filter 270, and an image plane 280, and the electronic sensing element 290 is disposed on the image plane 280 of the image capturing lens system, wherein the number of the lens elements in the image capturing lens system is six (210 and 260), and an air space is provided between any two adjacent lens elements in the image capturing lens system.

The first lens element 210 with negative refractive power has an object-side surface 211 being concave in a paraxial region thereof and an image-side surface 212 being concave in a paraxial region thereof. In addition, the object-side surface 211 of the first lens element includes at least one convex surface at an off-axis position.

The second lens element 220 with negative refractive power has a convex object-side surface 221 and a concave image-side surface 222.

The third lens element 230 with positive refractive power has a convex object-side surface 231 and a convex image-side surface 232.

The fourth lens element 240 with positive refractive power has a convex object-side surface 241 and a convex image-side surface 242.

The fifth lens element 250 with negative refractive power has an object-side surface 251 being concave in a paraxial region thereof and an image-side surface 252 being convex in a paraxial region thereof. In addition, the image-side surface 252 of the fifth lens element includes at least one concave surface on the off-axis side.

The sixth lens element 260 with negative refractive power has an object-side surface 261 being convex in a paraxial region thereof and an image-side surface 262 being concave in a paraxial region thereof. In addition, the image-side surface 262 of the sixth lens element includes at least one convex surface at an off-axis position.

The ir-cut filter 270 is made of glass, and is disposed between the sixth lens element 260 and the image plane 280 without affecting the focal length of the image capturing lens system.

The following third and fourth tables are referred to in combination.

In the second embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the following parameters are defined in the same way as in the first embodiment and will not be described herein.

The following data can be calculated by matching table three and table four:

in addition, in the image capturing lens system of the second embodiment, the focal length of the first lens element 210 is f1, the focal length of the second lens element 220 is f2, the focal length of the third lens element 230 is f3, the focal length of the fourth lens element 240 is f4, the focal length of the fifth lens element 250 is f5, and the focal length of the sixth lens element 260 is f6, where | f1|, | f2|, | f3|, | f4|, | f5|, and | f6| have a minimum value of | f4 |.

< third embodiment >

Referring to fig. 5 and fig. 6, wherein fig. 5 is a schematic diagram of an image capturing apparatus according to a third embodiment of the present invention, and fig. 6 is a graph of spherical aberration, astigmatism and distortion of the third embodiment in order from left to right. As shown in fig. 5, the image capturing device of the third embodiment includes an image capturing lens system (not shown) and an electronic photosensitive element 390. The image capturing lens system includes, in order from an object side to an image side, a first lens element 310, an aperture stop 300, a second lens element 320, a third lens element 330, a fourth lens element 340, a fifth lens element 350, a sixth lens element 360, an ir-cut filter 370 and an image plane 380, and the electronic sensor 390 is disposed on the image plane 380 of the image capturing lens system, wherein the number of the lens elements in the image capturing lens system is six (310 and 360), and an air space is provided between any two adjacent lens elements in the image capturing lens system.

The first lens element 310 with negative refractive power has an object-side surface 311 being concave in a paraxial region thereof and an image-side surface 312 being concave in a paraxial region thereof. In addition, the object-side surface 311 of the first lens element includes at least one convex surface at an off-axis position.

The second lens element 320 with positive refractive power has a concave object-side surface 321 and a convex image-side surface 322.

The third lens element 330 with positive refractive power has a concave object-side surface 331 and a convex image-side surface 332.

The fourth lens element 340 with positive refractive power has a convex object-side surface 341 and a convex image-side surface 342.

The fifth lens element 350 with negative refractive power has an object-side surface 351 being concave in a paraxial region thereof and an image-side surface 352 being convex in a paraxial region thereof. In addition, the image-side surface 352 of the fifth lens element includes at least one concave surface located off-axis.

The sixth lens element 360 with negative refractive power has an object-side surface 361 being convex in a paraxial region thereof and an image-side surface 362 being concave in a paraxial region thereof. In addition, the sixth lens element image-side surface 362 includes at least one convex surface at an off-axis position.

The ir-cut filter 370 is made of glass, and is disposed between the sixth lens element 360 and the image plane 380 without affecting the focal length of the image capturing lens system.

See also table five and table six below.

In the third embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the following parameters are defined in the same way as in the first embodiment and will not be described herein.

The following data can be derived by matching table five and table six:

in addition, in the image capturing lens system of the third embodiment, the focal length of the first lens element 310 is f1, the focal length of the second lens element 320 is f2, the focal length of the third lens element 330 is f3, the focal length of the fourth lens element 340 is f4, the focal length of the fifth lens element 350 is f5, and the focal length of the sixth lens element 360 is f6, where | f1|, | f2|, | f3|, | f4|, | f5|, and | f6| have a minimum value of | f4 |.

< fourth embodiment >

Referring to fig. 7 and 8, wherein fig. 7 is a schematic diagram of an image capturing apparatus according to a fourth embodiment of the invention, and fig. 8 is a graph of spherical aberration, astigmatism and distortion of the fourth embodiment in order from left to right. As shown in fig. 7, the image capturing device of the fourth embodiment includes an image capturing lens system (not shown) and an electronic photosensitive element 490. The image capturing lens system includes, in order from an object side to an image side, a first lens element 410, an aperture stop 400, a second lens element 420, a third lens element 430, a fourth lens element 440, a fifth lens element 450, a sixth lens element 460, an ir-cut filter 470 and an image plane 480, and the electronic sensing element 490 is disposed on the image plane 480 of the image capturing lens system, wherein the image capturing lens system includes six lens elements (410 and 460), and an air space is disposed between any two adjacent lens elements in the image capturing lens system.

The first lens element 410 with negative refractive power has an object-side surface 411 being concave in a paraxial region thereof and an image-side surface 412 being concave in a paraxial region thereof. In addition, the object-side surface 411 of the first lens element includes at least one convex surface at an off-axis position.

The second lens element 420 with negative refractive power has a convex object-side surface 421 and a concave image-side surface 422.

The third lens element 430 with positive refractive power has a convex object-side surface 431 and a convex image-side surface 432.

The fourth lens element 440 with positive refractive power has a convex object-side surface 441 and a convex image-side surface 442.

The fifth lens element 450 with negative refractive power has an object-side surface 451 being concave in a paraxial region thereof and an image-side surface 452 being convex in a paraxial region thereof. In addition, the image-side surface 452 of the fifth lens element includes at least one concave surface located off-axis.

The sixth lens element 460 with negative refractive power has an object-side surface 461 being convex in a paraxial region thereof and an image-side surface 462 being concave in a paraxial region thereof. In addition, the sixth lens element image-side surface 462 includes at least one convex surface at an off-axis position.

The ir-cut filter 470 is made of glass, and disposed between the sixth lens element 460 and the image plane 480 without affecting the focal length of the image capturing lens system.

See also table seven and table eight below.

In the fourth embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the following parameters are defined in the same way as in the first embodiment and will not be described herein.

The following data can be derived by matching table seven and table eight:

in addition, in the image capturing lens system of the fourth embodiment, the focal length of the first lens element 410 is f1, the focal length of the second lens element 420 is f2, the focal length of the third lens element 430 is f3, the focal length of the fourth lens element 440 is f4, the focal length of the fifth lens element 450 is f5, and the focal length of the sixth lens element 460 is f6, where | f1|, | f2|, | f3|, | f4|, | f5|, and | f6| have a minimum value of | f4 |.

< fifth embodiment >

Referring to fig. 9 and 10, fig. 9 is a schematic diagram illustrating an image capturing device according to a fifth embodiment of the invention, and fig. 10 is a graph illustrating spherical aberration, astigmatism and distortion of the fifth embodiment in order from left to right. As shown in fig. 9, the image capturing device of the fifth embodiment includes an image capturing lens system (not shown) and an electronic photosensitive element 590. The image capturing lens system includes, in order from an object side to an image side, a first lens element 510, an aperture stop 500, a second lens element 520, a third lens element 530, a fourth lens element 540, a fifth lens element 550, a sixth lens element 560, an ir-cut filter element 570, and an image plane 580, and an electronic sensor 590 is disposed on the image plane 580 of the image capturing lens system, wherein the number of the lens elements in the image capturing lens system is six (510 and 560), and an air space is disposed between any two adjacent lens elements in the image capturing lens system.

The first lens element 510 with negative refractive power has an object-side surface 511 being concave in a paraxial region thereof and an image-side surface 512 being concave in a paraxial region thereof. In addition, the object-side surface 511 of the first lens element includes at least one convex surface at an off-axis position.

The second lens element 520 with positive refractive power has a convex object-side surface 521 and a convex image-side surface 522.

The third lens element 530 with positive refractive power has a concave object-side surface 531 and a convex image-side surface 532.

The fourth lens element 540 with positive refractive power has a convex object-side surface 541 and a convex image-side surface 542.

The fifth lens element 550 with negative refractive power has an object-side surface 551 which is concave in a paraxial region thereof and an image-side surface 552 which is convex in a paraxial region thereof. In addition, the image-side surface 552 of the fifth lens element includes at least one concave surface on an off-axis basis.

The sixth lens element 560 with negative refractive power has an object-side surface 561 being convex in a paraxial region thereof and an image-side surface 562 being concave in a paraxial region thereof. In addition, the sixth lens element side surface 562 comprises at least one convex surface off-axis.

The ir-cut filter 570 is made of glass, and is disposed between the sixth lens element 560 and the image plane 580 without affecting the focal length of the image capturing lens system.

Reference is again made to table nine and table ten below.

In the fifth embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the following parameters are defined in the same way as in the first embodiment and will not be described herein.

The following data can be derived from tables nine and ten:

in addition, in the image capturing lens system of the fifth embodiment, the focal length of the first lens 510 is f1, the focal length of the second lens 520 is f2, the focal length of the third lens 530 is f3, the focal length of the fourth lens 540 is f4, the focal length of the fifth lens 550 is f5, and the focal length of the sixth lens 560 is f6, where | f4| is the minimum value among | f1|, | f2|, | f3|, | f4|, | f5|, and | f6 |.

< sixth embodiment >

Referring to fig. 11 and 12, wherein fig. 11 is a schematic diagram illustrating an image capturing device according to a sixth embodiment of the invention, and fig. 12 is a graph illustrating spherical aberration, astigmatism and distortion in the sixth embodiment from left to right. As shown in fig. 11, the image capturing device of the sixth embodiment includes an image capturing lens system (not shown) and an electronic photosensitive element 690. The image capturing lens system includes, in order from an object side to an image side, a first lens element 610, an aperture stop 600, a second lens element 620, a third lens element 630, a fourth lens element 640, a fifth lens element 650, a sixth lens element 660, an ir-cut filter element 670, and an image plane 680, and an electronic sensor 690 is disposed on the image plane 680 of the image capturing lens system, wherein the number of the lens elements in the image capturing lens system is six (610 and 660), and an air space is provided between any two adjacent lens elements in the image capturing lens system on an optical axis.

The first lens element 610 with negative refractive power has an object-side surface 611 being concave in a paraxial region thereof and an image-side surface 612 being concave in a paraxial region thereof. In addition, the object-side surface 611 of the first lens element includes at least one convex surface at an off-axis position.

The second lens element 620 with positive refractive power has a concave object-side surface 621 and a convex image-side surface 622.

The third lens element 630 with positive refractive power has a concave object-side surface 631 and a convex image-side surface 632.

The fourth lens element 640 with positive refractive power has a convex object-side surface 641 and a convex image-side surface 642.

The fifth lens element 650 with negative refractive power has an object-side surface 651 being concave in a paraxial region thereof and an image-side surface 652 being convex in a paraxial region thereof. Additionally, the fifth lens image-side surface 652 comprises at least one concave surface located off-axis.

The sixth lens element 660 with negative refractive power has an object-side surface 661 being convex in a paraxial region thereof and an image-side surface 662 being concave in a paraxial region thereof. In addition, the sixth lens element image-side surface 662 includes at least one convex surface at an off-axis position.

The ir-cut filter 670 is made of glass, and is disposed between the sixth lens element 660 and the image plane 680 without affecting the focal length of the image capturing lens system.

Reference is again made to the following table eleven and table twelve.

In the sixth embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the following parameters are defined in the same way as in the first embodiment and will not be described herein.

The following data can be derived from table eleven and table twelve:

in addition, in the image capturing lens system of the sixth embodiment, the focal length of the first lens 610 is f1, the focal length of the second lens 620 is f2, the focal length of the third lens 630 is f3, the focal length of the fourth lens 640 is f4, the focal length of the fifth lens 650 is f5, and the focal length of the sixth lens 660 is f6, where | f4| is the minimum value among | f1|, | f2|, | f3|, | f4|, | f5|, and | f6 |.

< seventh embodiment >

Referring to fig. 13 and 14, wherein fig. 13 is a schematic diagram of an image capturing apparatus according to a seventh embodiment of the invention, and fig. 14 is a graph of spherical aberration, astigmatism and distortion of the seventh embodiment sequentially from left to right. As shown in fig. 13, the image capturing device of the seventh embodiment includes an image capturing lens system (not shown) and an electronic photosensitive element 790. The image capturing lens system includes, in order from an object side to an image side, a first lens element 710, an aperture stop 700, a second lens element 720, a third lens element 730, a fourth lens element 740, a fifth lens element 750, a sixth lens element 760, an ir-cut filter 770, and an image plane 780, and the electronic sensing element 790 is disposed on the image plane 780 of the image capturing lens system, wherein the number of the lens elements in the image capturing lens system is six (710 and 760), and an air space is disposed between any two adjacent lens elements in the image capturing lens system.

The first lens element 710 with negative refractive power has an object-side surface 711 being concave in a paraxial region thereof and an image-side surface 712 being concave in a paraxial region thereof. In addition, the object-side surface 711 of the first lens element includes at least one convex surface at an off-axis position.

The second lens element 720 with positive refractive power has a convex object-side surface 721 and a concave image-side surface 722.

The third lens element 730 with positive refractive power has a concave object-side surface 731 and a convex image-side surface 732.

The fourth lens element 740 with positive refractive power has a convex object-side surface 741 and a convex image-side surface 742.

The fifth lens element 750 with negative refractive power has an object-side surface 751 being concave in a paraxial region thereof and an image-side surface 752 being convex in a paraxial region thereof. In addition, the image-side surface 752 of the fifth lens element includes at least one concave surface on the off-axis.

The sixth lens element 760 with positive refractive power has an object-side surface 761 being convex in a paraxial region thereof and an image-side surface 762 being concave in a paraxial region thereof. In addition, the sixth lens element includes at least one convex surface on the image-side surface 762 off-axis.

The ir-cut filter 770 is made of glass and disposed between the sixth lens element 760 and the image plane 780 without affecting the focal length of the image capturing lens system.

Reference is again made to the following thirteen and fourteen tables.

In the seventh embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the following parameters are defined in the same way as in the first embodiment and will not be described herein.

The following data can be derived from table thirteen and table fourteen:

in addition, in the image capturing lens system of the seventh embodiment, the focal length of the first lens 710 is f1, the focal length of the second lens 720 is f2, the focal length of the third lens 730 is f3, the focal length of the fourth lens 740 is f4, the focal length of the fifth lens 750 is f5, and the focal length of the sixth lens 760 is f6, where | f4| is the minimum value among | f1|, | f2|, | f3|, | f4|, | f5|, and | f6 |.

< eighth embodiment >

Referring to fig. 15 and 16, wherein fig. 15 is a schematic diagram of an image capturing apparatus according to an eighth embodiment of the present invention, and fig. 16 is a graph illustrating spherical aberration, astigmatism and distortion of the eighth embodiment in order from left to right. As shown in fig. 15, the image capturing device of the eighth embodiment includes an image capturing lens system (not shown) and an electronic photosensitive element 890. The image capturing lens system includes, in order from an object side to an image side, a first lens element 810, an aperture stop 800, a second lens element 820, a third lens element 830, a fourth lens element 840, a fifth lens element 850, a sixth lens element 860, an ir-cut filter 870, and an image plane 880, and the electronic sensor 890 is disposed on the image plane 880, wherein the image capturing lens system includes six lens elements (810 and 860), and an air space is disposed between any two adjacent lens elements in the image capturing lens system.

The first lens element 810 with negative refractive power has an object-side surface 811 being convex in a paraxial region thereof and an image-side surface 812 being concave in a paraxial region thereof.

The second lens element 820 with negative refractive power has a concave object-side surface 821 and a concave image-side surface 822.

The third lens element 830 with positive refractive power has a concave object-side surface 831 and a convex image-side surface 832.

The fourth lens element 840 with positive refractive power has a convex object-side surface 841 and a convex image-side surface 842.

The fifth lens element 850 with negative refractive power has an object-side surface 851 being concave in a paraxial region thereof and an image-side surface 852 being convex in a paraxial region thereof. In addition, the image-side surface 852 of the fifth lens element comprises at least one concave surface at an off-axis position.

The sixth lens element 860 with negative refractive power has an object-side surface 861 being convex in a paraxial region thereof and an image-side surface 862 being concave in the paraxial region thereof. In addition, the image-side surface 862 of the sixth lens element includes at least one convex surface at an off-axis position.

The ir-cut filter 870 is made of glass, and disposed between the sixth lens element 860 and the image plane 880 and does not affect the focal length of the image capturing lens system.

See also table fifteen below and table sixteen.

In the eighth embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the following parameters are defined in the same way as in the first embodiment and will not be described herein.

The following data can be derived from the table fifteen and table sixteen:

in addition, in the image capturing lens system of the eighth embodiment, the focal length of the first lens 810 is f1, the focal length of the second lens 820 is f2, the focal length of the third lens 830 is f3, the focal length of the fourth lens 840 is f4, the focal length of the fifth lens 850 is f5, and the focal length of the sixth lens 860 is f6, where | f4| is the minimum value among | f1|, | f2|, | f3|, | f4|, | f5|, and | f6 |.

< ninth embodiment >

Fig. 17 is a schematic diagram illustrating an electronic device 10 according to a ninth embodiment of the invention. The electronic device 10 of the ninth embodiment is a smart phone, and the electronic device 10 includes an image capturing device 11, and the image capturing device 11 includes an image capturing lens system (not shown) according to the invention and an electronic photosensitive element (not shown), wherein the electronic photosensitive element is disposed on an image plane of the image capturing lens system.

< tenth embodiment >

Fig. 18 is a schematic diagram illustrating an electronic device 20 according to a tenth embodiment of the invention. The electronic device 20 of the tenth embodiment is a tablet computer, and the electronic device 20 includes an image capturing device 21, and the image capturing device 21 includes an image capturing lens system (not shown) according to the invention and an electronic photosensitive element (not shown), wherein the electronic photosensitive element is disposed on an image plane of the image capturing lens system.

< eleventh embodiment >

Fig. 19 is a schematic diagram illustrating an electronic device 30 according to an eleventh embodiment of the invention. The electronic Device 30 of the eleventh embodiment is a Wearable Device (Wearable Device), the electronic Device 30 includes an image capturing Device 31, the image capturing Device 31 includes an image capturing lens system (not shown) according to the present invention, and an electronic photosensitive element (not shown), wherein the electronic photosensitive element is disposed on an image plane of the image capturing lens system.

Although the present invention has been described with reference to the above embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention.

Claims

1. An image capturing lens system, in order from an object side to an image side, comprising:

a first lens element with negative refractive power having an object-side surface being concave at a paraxial region thereof and including at least one convex surface at an off-axis region thereof;

a second lens element;

a third lens element;

a fourth lens element with positive refractive power;

a fifth lens element with negative refractive power; and

a sixth lens element having a concave image-side surface at a paraxial region thereof and at least one convex surface at an off-axis region thereof, wherein the object-side surface and the image-side surface thereof are aspheric;

wherein, the image capturing lens system has six lenses, at least three lenses are made of plastic material, an air space is provided between any two adjacent lenses in the image capturing lens system on the optical axis, the distance between the first lens and the second lens on the optical axis is T12, the distance between the fifth lens and the sixth lens on the optical axis is T56, the focal length of the first lens is f1, the focal length of the second lens is f2, and the focal length of the fifth lens is f5, which satisfies the following conditions:

1.10<T56/T12；

l f1/f2 l < 2.0; and

|f5/f2|<1.50。

2. the imaging lens system of claim 1, wherein the first lens element and the second lens element are separated by a distance T12, and the fifth lens element and the sixth lens element are separated by a distance T56, wherein the following conditions are satisfied:

1.25<T56/T12<4.0。

3. the imaging lens system of claim 1, wherein the third lens element has an object-side surface being concave at a paraxial region and an image-side surface being convex at a paraxial region.

4. The imaging lens system of claim 1, further comprising:

an aperture stop disposed between the first lens element and the third lens element, wherein an aperture value of the taking lens system is Fno, which satisfies the following condition:

1.6<Fno≤2.65。

5. the imaging lens system of claim 1, wherein the first lens element has a focal length of f1, the second lens element has a focal length of f2, the third lens element has a focal length of f3, the fourth lens element has a focal length of f4, the fifth lens element has a focal length of f5, and the sixth lens element has a focal length of f6, wherein | f4| is the minimum value among | f1|, | f2|, | f3|, | f4|, | f5|, and | f6 |.

6. The imaging lens system of claim 1, wherein the focal length of the imaging lens system is f, the focal length of the third lens element is f3, and the focal length of the fourth lens element is f4, which satisfies the following conditions:

1.5<|f/f3|+|f/f4|<3.0。

7. the imaging lens system of claim 1, wherein the sixth lens element has negative refractive power.

8. The imaging lens system of claim 1, wherein the thickness of the fifth lens element along the optical axis is CT5, the thickness of the sixth lens element along the optical axis is CT6, and the distance between the fifth lens element and the sixth lens element along the optical axis is T56, which satisfies the following conditions:

0.85<T56/(CT5+CT6)<2.0。

9. the imaging lens system of claim 1, wherein an axial distance between the first lens element and the second lens element is T12, an axial distance between the second lens element and the third lens element is T23, an axial distance between the third lens element and the fourth lens element is T34, an axial distance between the fourth lens element and the fifth lens element is T45, and an axial distance between the fifth lens element and the sixth lens element is T56, wherein the following conditions are satisfied:

2.5<(T12+T56)/(T23+T34+T45)<25。

10. the imaging lens system of claim 1, wherein the first lens element has an optical thickness CT1, and the second lens element has an optical thickness CT2, satisfying the following requirements:

0.10<CT2/CT1<0.70。

11. the imaging lens system of claim 1, wherein a focal length of the imaging lens system is f, a radius of curvature of the object-side surface of the second lens element is R3, and a radius of curvature of the image-side surface of the second lens element is R4, wherein the following conditions are satisfied:

|f/R3|+|f/R4|<1.0。

12. the imaging lens system of claim 1, wherein a focal length of the imaging lens system is f, a maximum effective radius of the image-side surface of the sixth lens element is Y62, and the following conditions are satisfied:

0.90<Y62/f<1.30。

13. the imaging lens system of claim 1, wherein an object-side surface of the sixth lens element is convex at a paraxial region thereof.

14. An image capturing device, comprising:

the imaging lens system of claim 1; and

an electronic photosensitive element disposed on an imaging surface of the image capturing lens system.

15. An image capturing lens system, in order from an object side to an image side, comprising:

a first lens element with negative refractive power;

a second lens element;

a third lens element;

a fourth lens element with positive refractive power;

a fifth lens element with negative refractive power; and

wherein the image capturing lens system comprises six lenses, at least three lenses are made of plastic material, an air gap is formed between any two adjacent lenses in the image capturing lens system on an optical axis, a distance between the first lens and the second lens on the optical axis is T12, a distance between the fifth lens and the sixth lens on the optical axis is T56, a focal length of the first lens is f1, a focal length of the second lens is f2, a focal length of the fifth lens is f5, an abbe number of the first lens is V1, an abbe number of the second lens is V2, an abbe number of the third lens is V3, an abbe number of the fourth lens is V4, an abbe number of the fifth lens is V5, and an abbe number of the sixth lens is V6, and the following conditions are satisfied:

1.10<T56/T12；

|f1/f2|<2.0；

l f5/f2 l < 1.50; and

1.90<(V1+V3+V4)/(V2+V5+V6)<3.5。

16. the imaging lens system of claim 15, wherein the first lens element and the second lens element are separated by a distance T12, and the fifth lens element and the sixth lens element are separated by a distance T56, wherein the following conditions are satisfied:

1.40<T56/T12<3.0。

17. the imaging lens system of claim 15, wherein the third lens element has an object-side surface being concave at a paraxial region and an image-side surface being convex at a paraxial region.

18. The imaging lens system of claim 15, further comprising:

1.6<Fno≤2.65。

19. the imaging lens system of claim 15, wherein the first lens element has a focal length of f1, the second lens element has a focal length of f2, the third lens element has a focal length of f3, the fourth lens element has a focal length of f4, the fifth lens element has a focal length of f5, and the sixth lens element has a focal length of f6, wherein | f4| is the minimum value among | f1|, | f2|, | f3|, | f4|, | f5|, and | f6 |.

20. The imaging lens system of claim 15, wherein the focal length of the imaging lens system is f, the focal length of the third lens element is f3, and the focal length of the fourth lens element is f4, which satisfies the following conditions:

1.5<|f/f3|+|f/f4|<3.0。

21. the imaging lens system of claim 15, wherein the sixth lens element has negative refractive power.

22. The imaging lens system of claim 15, wherein the thickness of the fifth lens element along the optical axis is CT5, the thickness of the sixth lens element along the optical axis is CT6, and the distance between the fifth lens element and the sixth lens element along the optical axis is T56, which satisfies the following condition:

0.85<T56/(CT5+CT6)<2.0。

23. the imaging lens system of claim 15, wherein an axial distance between the first lens element and the second lens element is T12, an axial distance between the second lens element and the third lens element is T23, an axial distance between the third lens element and the fourth lens element is T34, an axial distance between the fourth lens element and the fifth lens element is T45, and an axial distance between the fifth lens element and the sixth lens element is T56, wherein the following conditions are satisfied:

2.5<(T12+T56)/(T23+T34+T45)<25。

24. the imaging lens system of claim 15, wherein the first lens element has an optical thickness CT1, and the second lens element has an optical thickness CT2, satisfying the following requirements:

0.10<CT2/CT1<0.70。

25. the imaging lens system of claim 15, wherein a focal length of the imaging lens system is f, a radius of curvature of the object-side surface of the second lens element is R3, and a radius of curvature of the image-side surface of the second lens element is R4, wherein the following conditions are satisfied:

|f/R3|+|f/R4|<1.0。

26. the imaging lens system of claim 15, wherein a focal length of the imaging lens system is f, a maximum effective radius of the image-side surface of the sixth lens element is Y62, and the following conditions are satisfied:

0.90<Y62/f<1.30。

27. the imaging lens system of claim 15, wherein an object-side surface of the sixth lens element is convex at a paraxial region thereof.

28. An image capturing device, comprising:

the imaging lens system of claim 15; and