CN114063245B

CN114063245B - Six-piece wide-angle lens group

Info

Publication number: CN114063245B
Application number: CN202010770089.5A
Authority: CN
Inventors: 李钧胜
Original assignee: Xinju Technology Co ltd
Current assignee: Xinju Technology Co ltd
Priority date: 2020-08-04
Filing date: 2020-08-04
Publication date: 2022-09-30
Anticipated expiration: 2040-08-04
Also published as: CN114063245A

Abstract

The invention discloses a six-piece wide-angle lens group, which comprises the following components in sequence from an object side to an image side: a first lens element with negative refractive power, an aperture stop, a second lens element with positive refractive power, a third lens element with negative refractive power, a fourth lens element with positive refractive power, a fifth lens element with positive refractive power, and a sixth lens element with negative refractive power; wherein the first lens element has an optical axis thickness of CT1, the third lens element has an optical axis thickness of CT3, the fourth lens element has an optical axis thickness of CT4, the fifth lens element has an optical axis thickness of CT5, and the sixth lens element has an optical axis thickness of CT6, and the following conditions are satisfied: 0.82< (CT4+ CT5)/(CT1+ CT3+ CT6) < 1.96; 2.07< (CT1+ CT6)/CT3< 5.52. Therefore, the invention provides a six-piece wide-angle lens group with wide visual angle, high resolution capability, short lens length and small distortion on the premise of considering the lens productivity.

Description

Six-piece wide-angle lens group

Technical Field

The present invention relates to a six-piece wide-angle lens set, and more particularly to a miniaturized six-piece wide-angle lens set applied to electronic products.

Background

With the rise of electronic products with a photographing function, the demand of optical systems is increasing. In order to obtain a wide shooting range in shooting, the angle of view of the lens is required to meet certain requirements, and thus the requirements for the shooting angle and the image quality of the lens are becoming stricter. In general, the field angle (FOV) of the lens is designed to be 50 to 60 degrees, and if the field angle exceeds the designed angle, not only is the aberration large, but also the design of the lens is complicated. In the prior art, US 8335043 and US 8576497 use 2 lens groups, 5-6 lens groups to achieve the purpose of large angle, but the distortion (distortion) is too large, and for example, US 8593737, US 8576497 and US 8395853 can achieve the purpose of large angle, but the Total Length (TL) of the lens group is too long.

Therefore, how to develop a miniaturized six-piece wide-angle lens set, which can be disposed in electronic products such as a lens for a digital camera, a lens for a network camera, or a mobile phone lens, and which has a wide viewing angle, high resolution, a short lens length, and a small distortion while considering the productivity of the lens, is an motivation for the present invention.

Disclosure of Invention

The present invention provides a six-piece wide-angle lens assembly, and more particularly, to a six-piece wide-angle lens assembly with wide viewing angle, high resolution, short lens length, and small distortion while considering lens productivity.

To achieve the above object, the present invention provides a six-lens wide-angle lens assembly, comprising an aperture stop and an optical assembly consisting of six lenses, in order from an object side to an image side: the first lens element with negative refractive power has an object-side surface being concave at a paraxial region thereof and an image-side surface being concave at a paraxial region thereof, and at least one of the object-side surface and the image-side surface of the first lens element is aspheric; the aperture; the second lens element with positive refractive power has an object-side surface being convex at a paraxial region thereof and an image-side surface being convex at a paraxial region thereof, and at least one of the object-side surface and the image-side surface of the second lens element is aspheric; the third lens element with negative refractive power has an object-side surface being convex at a paraxial region thereof and an image-side surface being concave at a paraxial region thereof, wherein at least one of the object-side surface and the image-side surface of the third lens element is aspheric; the fourth lens element with positive refractive power has an object-side surface being convex at a paraxial region thereof and an image-side surface being concave at a paraxial region thereof, and at least one of the object-side surface and the image-side surface of the fourth lens element is aspheric; the fifth lens element with positive refractive power has an object-side surface being convex at a paraxial region thereof, and an image-side surface being convex at a paraxial region thereof, wherein at least one of the object-side surface and the image-side surface of the fifth lens element is aspheric, and at least one of the object-side surface and the image-side surface of the fifth lens element has at least one inflection point; the sixth lens element with negative refractive power has an object-side surface being convex at a paraxial region thereof, and an image-side surface being concave at a paraxial region thereof, wherein at least one of the object-side surface and the image-side surface of the sixth lens element is aspheric, and at least one of the object-side surface and the image-side surface of the sixth lens element has at least one inflection point;

wherein the first lens element has an optical axis thickness of CT1, the third lens element has an optical axis thickness of CT3, the fourth lens element has an optical axis thickness of CT4, the fifth lens element has an optical axis thickness of CT5, and the sixth lens element has an optical axis thickness of CT6, and the following conditions are satisfied: 0.82< (CT4+ CT5)/(CT1+ CT3+ CT6) < 1.96; 2.07< (CT1+ CT6)/CT3< 5.52.

Accordingly, when the condition of (CT4+ CT5)/(CT1+ CT3+ CT6) is satisfied, the thickness distribution of the lenses in the six-piece wide-angle lens group can be further balanced, so as to avoid the improper use of space due to the excessive thickness difference of the lenses. When the condition of (CT1+ CT6)/CT3 is satisfied, the thickness distribution of the lenses in the six-piece wide-angle lens assembly can be further balanced, so as to avoid the improper space usage caused by the excessive thickness difference of the lenses, and simultaneously enhance the system control capability of the third lens.

Preferably, the overall focal length of the six-piece wide-angle lens group is f, and the combined focal length of the fourth lens element and the fifth lens element is f45, and the following conditions are satisfied: 0.45< f/f45< 1.34. Therefore, the fourth lens and the fifth lens can be matched with each other to correct off-axis aberration.

Preferably, the combined focal length of the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens is f23456, the overall focal length of the six-piece wide-angle lens group is f, and the following conditions are satisfied: 0.56< f/f23456< 1.51. Therefore, the six-piece wide-angle lens group has a large drawing angle, and the resolution capability can be remarkably improved.

Preferably, the focal length of the third lens is f3, the combined focal length of the fourth lens and the fifth lens is f45, and the following conditions are satisfied: -3.75< f3/f45< -1.62. Therefore, the refractive powers of the fourth lens element and the fifth lens element are suitable, and the sensitivity of the image pickup optical lens system can be effectively reduced.

Preferably, the focal length of the fourth lens and the focal length of the fifth lens are f45, the focal length of the sixth lens is f6, and the following conditions are satisfied: -6.04< f6/f45< -0.95. Therefore, the six-piece wide-angle lens group has large picture angle, high picture number and low lens height, and the resolution capability is obviously improved.

Preferably, the thickness of the fourth lens element along the optical axis is CT4, the thickness of the fifth lens element along the optical axis is CT5, and the thickness of the third lens element along the optical axis is CT3, and the following conditions are satisfied: 3.78< (CT4+ CT5)/CT3< 8.38. The thickness distribution of the lenses in the six-lens wide-angle lens group can be balanced, so that the phenomenon that the space is not used properly due to overlarge thickness difference of the lenses is avoided.

Preferably, the second lens element has a thickness CT2 along the optical axis, and the third lens element has a thickness CT3 along the optical axis, and the following conditions are satisfied: 2.41< CT2/CT3< 5.78. Therefore, the thickness ratio of the second lens element to the third lens element can be adjusted to balance the space distribution of the six-piece wide-angle lens assembly, thereby improving the yield and quality.

Preferably, the thickness of the sixth lens element along the optical axis is CT6, the thickness of the third lens element along the optical axis is CT3, and the following conditions are satisfied: 1.07< CT6/CT3< 2.86. Therefore, the thickness ratio of the third lens element to the sixth lens element can be adjusted to balance the space distribution of the six-lens-element wide-angle lens assembly, thereby improving the yield and quality and simultaneously enhancing the system control capability of the third lens element.

Preferably, the thickness of the fourth lens element along the optical axis is CT4, the thickness of the fifth lens element along the optical axis is CT5, and the thickness of the first lens element along the optical axis is CT1, and the following conditions are satisfied: 1.41< (CT4+ CT5)/CT1< 7.4. The thickness distribution of the lenses in the six-lens wide-angle lens group can be balanced, so that the phenomenon that the space is not used properly due to overlarge thickness difference of the lenses is avoided.

Preferably, a combined focal length of the second lens element, the third lens element, the fourth lens element, the fifth lens element and the sixth lens element is f23456, half of an imaging height of the six-piece wide-angle lens assembly at an imaging plane is IMH, and the following conditions are satisfied: 0.99< IMH/f23456< 1.98. Therefore, the balance between the reduction of the volume of the six-piece wide-angle lens group and the increase of the area of an imaging surface can be obtained.

Preferably, the overall focal length of the six-piece wide-angle lens set is f, and half of the imaging height of the six-piece wide-angle lens set, which can be captured on the imaging surface, is IMH, and the following conditions are satisfied: 0.9< IMH/f < 2.69. Therefore, the balance between the reduction of the volume of the six-piece wide-angle lens group and the increase of the area of an imaging surface can be obtained.

Preferably, an axial distance between the image-side surface of the sixth lens element and the image plane is BFL, an overall focal length of the six-lens wide-angle lens assembly is f, and the following conditions are satisfied: 0.79< f/BFL < 2.17. Therefore, the balance between the reduction of the volume of the six-piece wide-angle lens group and the increase of the area of an imaging surface can be obtained.

Preferably, half of the height of the six-lens wide-angle lens assembly captured on the image plane is IMH, the distance from the aperture to the image plane on the optical axis is CTSI, and the following conditions are satisfied: 0.73< CTSI/(IMH × 2) < 1.2. Therefore, the balance between the reduction of the volume of the six-piece wide-angle lens group and the increase of the area of an imaging surface can be obtained.

Drawings

FIG. 1A is a schematic view of a six-piece wide-angle lens assembly according to a first embodiment of the invention.

FIG. 1B is a graph showing the curvature of field and distortion of the image plane of the six-piece wide-angle lens assembly of the first embodiment in order from left to right.

FIG. 2A is a diagram of a six-lens wide-angle lens assembly according to a second embodiment of the present invention.

FIG. 2B is a graph showing the field curvature and distortion aberration curves of the six-piece wide-angle lens assembly of the second embodiment in order from left to right.

FIG. 3A is a diagram of a six-piece wide-angle lens assembly according to a third embodiment of the present invention.

FIG. 3B is a graph showing the field curvature and distortion yield curves of the six-piece wide-angle lens assembly of the second embodiment in order from left to right.

FIG. 4A is a diagram of a six-lens wide-angle lens assembly according to a fourth embodiment of the invention.

FIG. 4B is a graph of field curvature and distortion difference curves of the six-piece wide-angle lens assembly of the fourth embodiment, in order from left to right.

FIG. 5A is a diagram of a six-piece wide-angle lens assembly according to a fifth embodiment of the present invention.

Fig. 5B is a curvature of field and distortion curves of the six-piece wide-angle lens assembly of the fifth embodiment in order from left to right.

FIG. 6A is a diagram of a six-lens wide-angle lens assembly according to a sixth embodiment of the present invention.

FIG. 6B is a curved image plane and distortion curve of the six-piece wide-angle lens assembly of the sixth embodiment, in order from left to right.

FIG. 7A is a diagram of a six-piece wide-angle lens assembly according to a seventh embodiment of the invention.

FIG. 7B is a graph showing the field curvature and distortion compensation curves of the six-piece wide-angle lens assembly of the seventh embodiment, in order from left to right.

FIG. 8A is a diagram of a six-lens wide-angle lens assembly according to an eighth embodiment of the invention.

Fig. 8B is a graph sequentially showing the field curvature and distortion aberration curves of the six-piece wide-angle lens assembly of the eighth embodiment from left to right.

FIG. 9A is a diagram of a six-lens wide-angle lens assembly according to a ninth embodiment of the invention.

FIG. 9B is a graph showing the field curvature and distortion compensation curves of the sixth wide-angle lens assembly of the ninth embodiment in order from left to right.

FIG. 10A is a diagram of a six-piece wide-angle lens assembly according to the tenth embodiment of the invention.

Fig. 10B is a graph of field curvature and distortion aberration curves of the six-piece wide-angle lens assembly of the tenth embodiment, in order from left to right.

Fig. 11A is a schematic view of a six-piece wide-angle lens assembly according to an eleventh embodiment of the invention.

Fig. 11B is a curvature of field and distortion curve of the six-piece wide-angle lens assembly of the eleventh embodiment in order from left to right.

Description of the symbols in the drawings:

100. 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100 diaphragm

110. 210, 310, 410, 510, 610, 710, 810, 910, 1010, 1110: a first lens

111. 211, 311, 411, 511, 611, 711, 811, 911, 1011, 1111 object side surface

112. 212, 312, 412, 512, 612, 712, 812, 912, 1012, 1112 image side surface

120. 220, 320, 420, 520, 620, 720, 820, 920, 1020, 1120 second lens

121. 221, 321, 421, 521, 621, 721, 821, 921, 1021, 1121 object side surface

122. 222, 322, 422, 522, 622, 722, 822, 922, 1022, 1122 image side surface

130. 230, 330, 430, 530, 630, 730, 830, 930, 1030, 1130 a third lens

131. 231, 331, 431, 531, 631, 731, 831, 931, 1031, 1131 object side surface

132. 232, 332, 432, 532, 632, 732, 832, 932, 1032, 1132 image-side surface

140. 240, 340, 440, 540, 640, 740, 840, 940, 1040, 1140 fourth lens

141. 241, 341, 441, 541, 641, 741, 841, 941, 1041, and 1141, an object side surface

142. 242, 342, 442, 542, 642, 742, 842, 942, 1042, 1142 the image side surface

150. 250, 350, 450, 550, 650, 750, 850, 950, 1050, 1150: fifth lens

151. 251, 351, 451, 551, 651, 751, 851, 951, 1051, 1151, an object side surface

152. 252, 352, 452, 552, 652, 752, 852, 952, 1052, 1152 image side surface

160. 260, 360, 460, 560, 660, 760, 860, 960, 1060, 1160 sixth lens

161. 261, 361, 461, 561, 661, 761, 861, 961, 1061, 1161, the object side surface

162. 262, 362, 462, 562, 662, 762, 862, 962, 1062, 1162 image side surface

170. 270, 370, 470, 570, 670, 770, 870, 970, 1070, 1170 IR-filtering components

180. 280, 380, 480, 580, 680, 780, 880, 980, 1080, 1180 imaging plane

190. 290, 390, 490, 590, 690, 790, 890, 990, 1090, 1190 optical axis

f is focal length of six-piece wide-angle lens group

Fno is aperture value of six-piece wide-angle lens group

FOV is maximum field angle in six-piece wide-angle lens group

f3 focal length of third lens

f6 focal length of sixth lens

f45 composite focal length of fourth lens and fifth lens

f23456 composite focal Length of second, third, fourth, fifth, and sixth lenses

CT1 thickness of first lens on optical axis

CT3 thickness of third lens on optical axis

CT4 thickness of fourth lens on optical axis

CT5 thickness of fifth lens on optical axis

CT6 thickness of sixth lens on optical axis

IMH is half of the height of the six-piece wide-angle lens group at the imaging surface

BFL is the distance from the image side surface of the sixth lens element to the imaging plane on the optical axis

CTSI (computer-to-plate) is the distance between the diaphragm and the imaging surface on the optical axis

Detailed Description

The technical solutions of the present invention will be described clearly and completely below, and it should be apparent that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

First embodiment

Referring to fig. 1A and fig. 1B, fig. 1A is a schematic diagram of a six-piece wide-angle lens assembly according to a first embodiment of the invention, and fig. 1B is a graph of field curvature and distortion aberration of the six-piece wide-angle lens assembly of the first embodiment in order from left to right. In fig. 1A, the six-piece wide-angle lens assembly includes an aperture stop 100 and an optical assembly, which includes, in order from an object side to an image side, a first lens element 110, 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, wherein six lens elements have refractive power. The diaphragm 100 is disposed between the first lens 110 and the second lens 120.

The first lens element 110 with negative refractive power has an object-side surface 111 being concave at a paraxial region 190 thereof and an image-side surface 112 being concave at a paraxial region 190 thereof, wherein the object-side surface 111 and the image-side surface 112 are aspheric.

The second lens element 120 with positive refractive power has an object-side surface 121 being convex in a paraxial region 190 and an image-side surface 122 being convex in a paraxial region 190, and the object-side surface 121 and the image-side surface 122 are aspheric.

The third lens element 130 with negative refractive power has an object-side surface 131 being convex in a paraxial region 190 and an image-side surface 132 being concave in a paraxial region 190, wherein the third lens element 130 is made of plastic material, and both the object-side surface 131 and the image-side surface 132 are aspheric.

The fourth lens element 140 with positive refractive power has an object-side surface 141 being convex at a paraxial region 190 and an image-side surface 142 being concave at a paraxial region 190, and the object-side surface 141 and the image-side surface 142 are aspheric.

The fifth lens element 150 with positive refractive power has an object-side surface 151 being convex at a paraxial region 190 and an image-side surface 152 being convex at a paraxial region 190, wherein the object-side surface 151 and the image-side surface 152 are aspheric, and the object-side surface 151 has at least one inflection point.

The sixth lens element 160 with negative refractive power has an object-side surface 161 being convex at a paraxial region 190 and an image-side surface 162 being concave at a paraxial region 190, wherein the object-side surface 161 and the image-side surface 162 are aspheric and the object-side surface 161 and the image-side surface 162 have at least one inflection point.

The ir-cut filter assembly 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 six-piece wide-angle lens assembly.

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

wherein z is a position value referenced to the surface vertex at a position of height h along the optical axis 190; c is a curvature of the lens surface near the optical axis 190 and is an inverse of a curvature radius (R) (c is 1/R), R is a curvature radius of the lens surface near the optical axis 190, h is a perpendicular distance of the lens surface from the optical axis 190, k is a conic coefficient (conic constant), and A, B, C, D, E, F, … … are high order aspheric coefficients.

In the six-piece wide angle lens group of the first embodiment, the focal length of the six-piece wide angle lens group is f, the aperture value (f-number) of the six-piece wide angle lens group is Fno, and the maximum field angle (angle of view) of the six-piece wide angle lens group is FOV, which are as follows: f ═ 1.38 (millimeters); fno 2.07; and FOV 140.09 (degrees).

In the sixth wide-angle lens assembly of the first embodiment, the thickness of the first lens element 110 on the optical axis 190 is CT1, the thickness of the third lens element 130 on the optical axis 190 is CT3, the thickness of the fourth lens element 140 on the optical axis 190 is CT4, the thickness of the fifth lens element 150 on the optical axis 190 is CT5, and the thickness of the sixth lens element 160 on the optical axis 190 is CT6, and the following conditions are satisfied: (CT4+ CT5)/(CT1+ CT3+ CT6) ═ 1.353; (CT1+ CT6)/CT3 ═ 2.727.

In the six-piece wide angle lens group of the first embodiment, the overall focal length of the six-piece wide angle lens group is f, and the combined focal length of the fourth lens element 140 and the fifth lens element 150 is f45, and the following conditions are satisfied: f/f45 is 0.805.

In the six-piece wide-angle lens group of the first embodiment, the combined focal length of the second lens element 120, the third lens element 130, the fourth lens element 140, the fifth lens element 150 and the sixth lens element 160 is f23456, and the overall focal length of the six-piece wide-angle lens group is f, and the following conditions are satisfied: f/f23456 is 0.841.

In the sixth wide-angle lens group of the first embodiment, the focal length of the third lens element 130 is f3, and the combined focal length of the fourth lens element 140 and the fifth lens element 150 is f45, and the following conditions are satisfied: f3/f45 is-2.510.

In the sixth wide-angle lens group of the first embodiment, the combined focal length of the fourth lens element 140 and the fifth lens element 150 is f45, the focal length of the sixth lens element 160 is f6, and the following conditions are satisfied: f6/f45 ═ 1.590.

In the sixth wide-angle lens assembly of the first embodiment, the thickness of the fourth lens element 140 on the optical axis 190 is CT4, the thickness of the fifth lens element 150 on the optical axis 190 is CT5, and the thickness of the third lens element 130 on the optical axis 190 is CT3, and the following conditions are satisfied: (CT4+ CT5)/CT3 is 5.042.

In the sixth embodiment of the present invention, the thickness of the second lens element 120 on the optical axis 190 is CT2, the thickness of the third lens element 130 on the optical axis 190 is CT3, and the following conditions are satisfied: CT2/CT 3-3.397.

In the first embodiment of the six-lens wide-angle lens assembly, the thickness of the sixth lens element 160 on the optical axis 190 is CT6, the thickness of the third lens element 130 on the optical axis 190 is CT3, and the following conditions are satisfied: CT6/CT 3-1.401.

In the sixth wide-angle lens assembly of the first embodiment, the thickness of the fourth lens element 140 on the optical axis 190 is CT4, the thickness of the fifth lens element 150 on the optical axis 190 is CT5, and the thickness of the first lens element 110 on the optical axis 190 is CT1, which satisfies the following conditions: (CT4+ CT5)/CT1 ═ 3.804.

In the sixth wide-angle lens group of the first embodiment, wherein the combined focal length of the second lens element 120, the third lens element 130, the fourth lens element 140, the fifth lens element 150 and the sixth lens element 160 is f23456, half of the imaging height of the sixth wide-angle lens group at the imaging plane is IMH, and the following conditions are satisfied: IMH/f23456 equals 1.381.

In the six-piece wide angle lens assembly of the first embodiment, the overall focal length of the six-piece wide angle lens assembly is f, half of the imaging height of the six-piece wide angle lens assembly that can be captured at the imaging plane 180 is IMH, and the following conditions are satisfied: IMH/f is 1.642.

In the first embodiment of the six-lens wide-angle lens group, a distance BFL is defined between the image-side surface 162 of the sixth lens element 160 and the image plane 180, and an overall focal length f of the six-lens wide-angle lens group satisfies the following condition: f/BFL is 1.221.

In the first embodiment of the six-piece wide angle lens assembly, half of the height of the image captured by the image plane 180 is IMH, the distance from the aperture 100 to the image plane 180 on the optical axis 190 is CTSI, and the following conditions are satisfied: CTSI/(IMH × 2) ═ 0.961.

Further, refer to the following Table 1 and Table 2.

Table 1 shows the detailed structural data of the first embodiment of fig. 1A, wherein the unit of the radius of curvature, the thickness and the focal length is mm, and the surfaces 0-18 sequentially represent the surfaces from the object side to the image side, and include a testing surface (i.e., surface 1) and a light shielding surface (i.e., surface 7) for passing part of the light and shielding part of the light. Table 2 shows aspheric data in the first embodiment, where k denotes a cone coefficient in the aspheric curve equation, and A, B, C, D, E, F, G … denotes a higher-order aspheric coefficient. In addition, the following tables of the embodiments correspond to the schematic diagrams of the embodiments and the field curvature and distortion aberration curves, and the definitions of the data in the tables are the same as those in tables 1 and 2 of the first embodiment, which are not repeated herein.

Second embodiment

Referring to FIG. 2A and FIG. 2B, FIG. 2A is a schematic diagram of a six-piece wide angle lens assembly according to the second embodiment of the present invention, and FIG. 2B is a graph of field curvature and distortion aberration of the six-piece wide angle lens assembly in the second embodiment in order from left to right. In fig. 2A, the six-piece wide-angle lens assembly includes an aperture stop 200 and an optical assembly, which includes, in order from an object side to an image side, a first lens element 210, a second lens element 220, 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, wherein six lens elements have refractive power. The diaphragm 200 is disposed between the first lens 210 and the second lens 220.

The first lens element 210 with negative refractive power has an object-side surface 211 being concave at a paraxial region 290 thereof and an image-side surface 212 being concave at a paraxial region 290 thereof, and the object-side surface 211 and the image-side surface 212 are aspheric.

The second lens element 220 with positive refractive power has an object-side surface 221 being convex at a paraxial region 290 thereof and an image-side surface 222 being convex at a paraxial region 290 thereof, wherein the object-side surface 221 and the image-side surface 222 are aspheric.

The third lens element 230 with negative refractive power has an object-side surface 231 being convex at a paraxial region 290 and an image-side surface 232 being concave at a paraxial region 290, and both the object-side surface 231 and the image-side surface 232 are aspheric.

The fourth lens element 240 with positive refractive power has an object-side surface 241 being convex at a paraxial region 290 thereof and an image-side surface 242 being concave at a paraxial region 290 thereof, and the object-side surface 241 and the image-side surface 242 are aspheric.

The fifth lens element 250 with positive refractive power has an object-side surface 251 being convex in a paraxial region 290, an image-side surface 252 being convex in a paraxial region 290, the object-side surface 251 and the image-side surface 252 being aspheric, and the object-side surface 251 has at least one inflection point.

The sixth lens element 260 with negative refractive power has an object-side surface 261 being convex at a paraxial region 290, an image-side surface 262 being concave at a paraxial region 290, wherein the object-side surface 261 and the image-side surface 262 are aspheric, and both the object-side surface 261 and the image-side surface 262 have at least one inflection point.

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 six-piece wide-angle lens assembly.

Further, the following Table 3 and Table 4 are referred to.

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 derived from tables 3 and 4:

third embodiment

Referring to fig. 3A and 3B, fig. 3A is a schematic diagram of a six-piece wide-angle lens assembly according to a third embodiment of the invention, and fig. 3B is a graph of field curvature and distortion aberration of the six-piece wide-angle lens assembly of the third embodiment in order from left to right. In fig. 3A, the six-piece wide-angle lens assembly includes an aperture stop 300 and an optical assembly, which includes, in order from an object side to an image side, a first lens element 310, 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 and an image plane 380, wherein six lens elements have refractive power. The diaphragm 300 is disposed between the first lens 310 and the second lens 320.

The first lens element 310 with negative refractive power has an object-side surface 311 being concave at a paraxial region 390, an image-side surface 312 being concave at a paraxial region 390, and both the object-side surface 311 and the image-side surface 312 being aspheric.

The second lens element 320 with positive refractive power has an object-side surface 321 being convex at a paraxial region 390, and an image-side surface 322 being convex at a paraxial region 390, wherein the object-side surface 321 and the image-side surface 322 are aspheric.

The third lens element 330 with negative refractive power has an object-side surface 331 being convex at a paraxial region 390, an image-side surface 332 being concave at a paraxial region 390, and both the object-side surface 331 and the image-side surface 332 being aspheric.

The fourth lens element 340 with positive refractive power has an object-side surface 341 being convex at a paraxial region 390, an image-side surface 342 being concave at a paraxial region 390, and both the object-side surface 341 and the image-side surface 342 being aspheric.

The fifth lens element 350 with positive refractive power has an object-side surface 351 being convex in a paraxial region 390, an image-side surface 352 being convex in a paraxial region 390, the object-side surface 351 and the image-side surface 352 being aspheric, and the object-side surface 351 has at least one inflection point.

The sixth lens element 360 with negative refractive power has an object-side surface 361 being convex in a paraxial region 390 thereof and an image-side surface 362 being concave in the paraxial region 390 thereof, wherein the object-side surface 361 and the image-side surface 362 are aspheric, and the object-side surface 361 and the image-side surface 362 have at least one inflection point.

The ir-cut filter 370 is made of glass and disposed between the sixth lens element 360 and the image plane 380 without affecting the focal length of the six-piece wide-angle lens assembly.

Further, the following Table 5 and Table 6 were referred to.

In a third embodiment, the aspherical surface curve equation is given in the form of 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 5 and 6:

fourth embodiment

Referring to fig. 4A and 4B, fig. 4A is a schematic diagram of a six-piece wide-angle lens assembly according to a fourth embodiment of the invention, and fig. 4B is a graph of field curvature and distortion aberration of the six-piece wide-angle lens assembly of the fourth embodiment in order from left to right. In fig. 4A, the six-lens wide-angle lens assembly includes an aperture stop 400 and an optical assembly including, in order from an object side to an image side, a first lens element 410, 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 and an image plane 480, wherein six lens elements are included in the six-lens wide-angle lens assembly. The diaphragm 400 is disposed between the first lens 410 and the second lens 420.

The first lens element 410 with negative refractive power has an object-side surface 411 being concave at a paraxial region 490 thereof and an image-side surface 412 being concave at a paraxial region 490 thereof, and the object-side surface 411 and the image-side surface 412 are aspheric.

The second lens element 420 with positive refractive power has an object-side surface 421 being convex at a paraxial region 490 thereof and an image-side surface 422 being convex at a paraxial region 490 thereof, wherein the object-side surface 421 and the image-side surface 422 are aspheric.

The third lens element 430 with negative refractive power has an object-side surface 431 being convex at a paraxial region 490 thereof and an image-side surface 432 being concave at a paraxial region 490 thereof, and the object-side surface 431 and the image-side surface 432 are aspheric.

The fourth lens element 440 with positive refractive power has an object-side surface 441 being convex at a position close to an optical axis 490, an image-side surface 442 being concave at the position close to the optical axis 490, and both the object-side surface 441 and the image-side surface 442 being aspheric.

The fifth lens element 450 with positive refractive power has an object-side surface 451 being convex in a paraxial region 490 thereof and an image-side surface 452 being convex in a paraxial region 490 thereof, wherein the object-side surface 451 and the image-side surface 452 are aspheric, and the object-side surface 451 has at least one inflection point.

The sixth lens element 460 with negative refractive power has an object-side surface 461 being convex at a paraxial region 490 and an image-side surface 462 being concave at the paraxial region 490, wherein the object-side surface 461 and the image-side surface 462 are aspheric, and the object-side surface 461 and the image-side surface 462 both have at least one inflection point.

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 six-piece wide-angle lens assembly.

Further, the following Table 7 and Table 8 are referred to.

In the fourth embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the definitions of the parameters in the following table are the same as those of the first embodiment, and are not repeated herein.

The following data can be derived from tables 7 and 8:

fifth embodiment

Referring to fig. 5A and 5B, fig. 5A is a schematic diagram of a six-piece wide-angle lens assembly according to a fifth embodiment of the invention, and fig. 5B is a graph of field curvature and distortion aberration of the six-piece wide-angle lens assembly of the fifth embodiment in order from left to right. In fig. 5A, the six-lens wide-angle lens assembly includes an aperture stop 500 and an optical group comprising, in order from an object side to an image side, a first lens element 510, 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 and an image plane 580, wherein six lens elements have refractive power. The diaphragm 500 is disposed between the first lens 510 and the second lens 520.

The first lens element 510 with negative refractive power has an object-side surface 511 being concave in a paraxial region 590, an image-side surface 512 being concave in a paraxial region 590, and both the object-side surface 511 and the image-side surface 512 being aspheric.

The second lens element 520 with positive refractive power has an object-side surface 521 being convex in a paraxial region 590, and an image-side surface 522 being convex in a paraxial region 590, and the object-side surface 521 and the image-side surface 522 are aspheric.

The third lens element 530 with negative refractive power has an object-side surface 531 being convex at a paraxial region 590 and an image-side surface 532 being concave at a paraxial region 590, and both the object-side surface 531 and the image-side surface 532 are aspheric.

The fourth lens element 540 with positive refractive power has an object-side surface 541 being convex in a paraxial region 590, and an image-side surface 542 being concave in a paraxial region 590, wherein the object-side surface 541 and the image-side surface 542 are aspheric.

The fifth lens element 550 with positive refractive power has an object-side surface 551 being convex in a paraxial region 590, an image-side surface 552 being convex in a paraxial region 590, the object-side surface 551 and the image-side surface 552 being aspheric, and the object-side surface 551 has at least one inflection point.

The sixth lens element 560 with negative refractive power has an object-side surface 561 being convex in a paraxial region 590, an image-side surface 562 being concave in a paraxial region 590, the object-side surface 561 and the image-side surface 562 being aspheric, and the object-side surface 561 and the image-side surface 562 both have at least one inflection point.

The ir-cut filter 570 is made of glass and disposed between the sixth lens element 560 and the image plane 580 without affecting the focal length of the six-piece wide-angle lens assembly.

Further, the following table 9 and table 10 are referred to.

In the fifth embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the definitions of the parameters in the following table are the same as those of the first embodiment, and are not repeated herein.

The following data can be derived from tables 9 and 10:

sixth embodiment

Referring to fig. 6A and 6B, fig. 6A is a schematic diagram of a six-piece wide-angle lens assembly according to a sixth embodiment of the invention, and fig. 6B is a graph of field curvature and distortion aberration of the six-piece wide-angle lens assembly of the sixth embodiment in order from left to right. In fig. 6A, the six-piece wide-angle lens assembly includes an aperture stop 600 and an optical assembly, which includes, in order from an object side to an image side, a first lens element 610, 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 and an image plane 680, wherein six lens elements have refractive power. The diaphragm 600 is disposed between the first lens 610 and the second lens 620.

The first lens element 610 with negative refractive power has an object-side surface 611 being concave at a paraxial region 690 and an image-side surface 612 being concave at a paraxial region 690, and the object-side surface 611 and the image-side surface 612 are aspheric.

The second lens element 620 with positive refractive power has an object-side surface 621 being convex in a paraxial region 690 thereof and an image-side surface 622 being convex in a paraxial region 690 thereof, and the object-side surface 621 and the image-side surface 622 thereof are aspheric.

The third lens element 630 with negative refractive power has an object-side surface 631 being convex in a paraxial region 690 and an image-side surface 632 being concave in a paraxial region 690, wherein the object-side surface 631 and the image-side surface 632 are aspheric.

The fourth lens element 640 with positive refractive power has an object-side surface 641 being convex in a paraxial region 690 thereof, an image-side surface 642 being concave in the paraxial region 690 thereof, and the object-side surface 641 and the image-side surface 642 being aspheric.

The fifth lens element 650 with positive refractive power is made of plastic material, and has an object-side surface 651 being convex at a paraxial region 690 thereof and an image-side surface 652 being convex at a paraxial region 690 thereof, wherein the object-side surface 651 and the image-side surface 652 are aspheric, and the object-side surface 651 has at least one inflection point.

The sixth lens element 660 with negative refractive power has an object-side surface 661 being convex at a paraxial region 690, an image-side surface 662 being concave at a paraxial region 690, wherein the object-side surface 661 and the image-side surface 662 are aspheric, and the object-side surface 661 and the image-side surface 662 have at least one inflection point.

The ir-cut filter 670 is made of glass and disposed between the sixth lens element 660 and the image plane 680 without affecting the focal length of the six-lens wide-angle lens assembly.

Further, the following table 11 and table 12 are referred to.

In the sixth embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the definitions of the parameters in the following table are the same as those of the first embodiment, and are not repeated herein.

The following data can be derived from tables 11 and 12:

seventh embodiment

Referring to fig. 7A and 7B, fig. 7A is a schematic diagram of a six-piece wide-angle lens assembly according to a seventh embodiment of the invention, and fig. 7B is a graph of field curvature and distortion aberration curves of the six-piece wide-angle lens assembly of the seventh embodiment from left to right. In fig. 7A, the six-piece wide-angle lens assembly includes an aperture stop 700 and an optical assembly including, in order from an object side to an image side, a first lens element 710, 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 and an image plane 780, wherein six lens elements have refractive power. The diaphragm 700 is disposed between the first lens 710 and the second lens 720.

The first lens element 710 with negative refractive power has an object-side surface 711 being concave at a paraxial region 790, an image-side surface 712 being concave at a paraxial region 790, and both the object-side surface 711 and the image-side surface 712 being aspheric.

The second lens element 720 with positive refractive power has an object-side surface 721 being convex at a paraxial region 790, an image-side surface 722 being convex at a paraxial region 790, and both the object-side surface 721 and the image-side surface 722 being aspheric.

The third lens element 730 with negative refractive power has an object-side surface 731 being convex in a paraxial region 790, an image-side surface 732 being concave in a paraxial region 790, and both the object-side surface 731 and the image-side surface 732 being aspheric.

The fourth lens element 740 with positive refractive power is made of plastic material, and has an object-side surface 741 being convex in a paraxial region 790 and an image-side surface 742 being concave in the paraxial region 790, wherein the object-side surface 741 and the image-side surface 742 are aspheric.

The fifth lens element 750 with positive refractive power is made of plastic material, and has an object-side surface 751 being convex at a paraxial region 790, an image-side surface 752 being convex at a paraxial region 790, the object-side surface 751 and the image-side surface 752 being aspheric, and the object-side surface 751 has at least one inflection point.

The sixth lens element 760 with negative refractive power has an object-side surface 761 being convex at a paraxial region 790, an image-side surface 762 being concave at the paraxial region 790, both the object-side surface 761 and the image-side surface 762 being aspheric, and both the object-side surface 761 and the image-side surface 762 having at least one inflection point.

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 six-piece wide-angle lens assembly.

Further, the following table 13 and table 14 are referred to.

In the seventh embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the definitions of the parameters in the following table are the same as those of the first embodiment, and are not repeated herein.

The following data can be derived from the coordination tables 13 and 14:

eighth embodiment

Referring to fig. 8A and 8B, fig. 8A is a schematic diagram of a six-piece wide angle lens assembly according to an eighth embodiment of the invention, and fig. 8B is a graph of field curvature and distortion aberration curves of the six-piece wide angle lens assembly of the eighth embodiment from left to right. In fig. 8A, the six-piece wide-angle lens assembly includes an aperture stop 800 and an optical assembly including, in order from an object side to an image side, a first lens element 810, 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 and an image plane 880, wherein six lens elements have refractive power. The diaphragm 800 is disposed between the first lens 810 and the second lens 820.

The first lens element 810 with negative refractive power has an object-side surface 811 being concave in a paraxial region 890 thereof and an image-side surface 812 being concave in a paraxial region 890 thereof, wherein the object-side surface 811 and the image-side surface 812 are aspheric.

The second lens element 820 with positive refractive power has an object-side surface 821 being convex in a paraxial region 890 thereof and an image-side surface 822 being convex in a paraxial region 890 thereof, wherein the object-side surface 821 and the image-side surface 822 are aspheric.

The third lens element 830 with negative refractive power has an object-side surface 831 being convex in a paraxial region 890 thereof and an image-side surface 832 being concave in the paraxial region 890 thereof, wherein the object-side surface 831 and the image-side surface 832 are aspheric.

The fourth lens element 840 with positive refractive power has an object-side surface 841 being convex at a paraxial region 890 thereof and an image-side surface 842 being concave at a paraxial region 890 thereof, wherein the object-side surface 841 and the image-side surface 842 are aspheric.

The fifth lens element 850 with positive refractive power is made of plastic material, and has an object-side surface 851 being convex in a paraxial region 890 thereof and an image-side surface 852 being convex in a paraxial region 890 thereof, wherein the object-side surface 851 and the image-side surface 852 are aspheric and the object-side surface 851 has at least one inflection point.

The sixth lens element 860 with negative refractive power is made of plastic material, and has an object-side surface 861 being convex at a paraxial region 890, an image-side surface 862 being concave at the paraxial region 890, wherein the object-side surface 861 and the image-side surface 862 are aspheric, and the object-side surface 861 and the image-side surface 862 have at least one inflection point.

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 six-piece wide-angle lens assembly.

Further, the following Table 15 and Table 16 are referred to.

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 coordination tables 15 and 16:

ninth embodiment

Referring to fig. 9A and 9B, fig. 9A is a schematic diagram of a six-piece wide-angle lens assembly according to a ninth embodiment of the invention, and fig. 9B is a graph of field curvature and distortion aberration of the six-piece wide-angle lens assembly according to the ninth embodiment in order from left to right. In fig. 9A, the six-lens wide-angle lens assembly includes an aperture stop 900 and an optical assembly including, in order from an object side to an image side, a first lens element 910, a second lens element 920, a third lens element 930, a fourth lens element 940, a fifth lens element 950, a sixth lens element 960, and an image plane 980, wherein six lens elements have refractive power. The aperture stop 900 is disposed between the first lens 910 and the second lens 920.

The first lens element 910 with negative refractive power has an object-side surface 911 being concave at a paraxial region 990 and an image-side surface 912 being concave at a paraxial region 990, and is made of plastic material, wherein the object-side surface 911 and the image-side surface 912 are aspheric.

The second lens element 920 with positive refractive power has an object-side surface 921 being convex at a paraxial region 990 and an image-side surface 922 being convex at a paraxial region 990, wherein the second lens element 920 is made of plastic material, and both the object-side surface 921 and the image-side surface 922 are aspheric.

The third lens element 930 with negative refractive power has an object-side surface 931 being convex at a paraxial region 990 and an image-side surface 932 being concave at a paraxial region 990, and is made of plastic material.

The fourth lens element 940 with positive refractive power has an object-side surface 941 being convex at a paraxial region 990 and an image-side surface 942 being concave at the paraxial region 990, and is made of plastic material, wherein the object-side surface 941 and the image-side surface 942 are aspheric.

The fifth lens element 950 with positive refractive power has an object-side surface 951 being convex at a paraxial region 990 and an image-side surface 952 being convex at a paraxial region 990, wherein the object-side surface 951 and the image-side surface 952 are aspheric, and the object-side surface 951 has at least one inflection point.

The sixth lens element 960 with negative refractive power has an object-side surface 961 being convex at a paraxial region 990 and an image-side surface 962 being concave at a paraxial region 990, wherein the object-side surface 961 and the image-side surface 962 are aspheric, and the object-side surface 961 and the image-side surface 962 have at least one inflection point.

The ir-cut filter 970 is made of glass material and is disposed between the sixth lens element 960 and the image plane 980 without affecting the focal length of the six-piece wide-angle lens assembly.

Further, the following table 17 and table 18 are referred to.

In a ninth embodiment, the equation for the curve of the aspheric 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 tables 17 and 18:

tenth embodiment

Referring to fig. 10A and 10B, fig. 10A is a schematic diagram of a six-piece wide-angle lens assembly according to a tenth embodiment of the invention, and fig. 10B is a graph of field curvature and distortion aberration curves of the six-piece wide-angle lens assembly of the tenth embodiment in order from left to right. In fig. 10A, the six-piece wide-angle lens assembly includes an aperture stop 1000 and an optical assembly including, in order from an object side to an image side, a first lens element 1010, a second lens element 1020, a third lens element 1030, a fourth lens element 1040, a fifth lens element 1050, a sixth lens element 1060 and an image plane 1080, wherein six lens elements have refractive power. The diaphragm 1000 is disposed between the first lens 1010 and the second lens 1020.

The first lens element 1010 with negative refractive power has an object-side surface 1011 being concave in a paraxial region 1090, an image-side surface 1012 being concave in a paraxial region 1090, and both the object-side surface 1011 and the image-side surface 1012 being aspheric.

The second lens element 1020 with positive refractive power has an object-side surface 1021 being convex in a paraxial region 1090 thereof and an image-side surface 1022 being convex in a paraxial region 1090 thereof, wherein the object-side surface 1021 and the image-side surface 1022 are aspheric.

The third lens element 1030 with negative refractive power has an object-side surface 1031 being convex in a position close to the optical axis 1090, an image-side surface 1032 being concave in a position close to the optical axis 1090, and both the object-side surface 1031 and the image-side surface 1032 being aspheric.

The fourth lens element 1040 with positive refractive power has an object-side surface 1041 being convex at a paraxial region 1090, an image-side surface 1042 being concave at a paraxial region 1090, and both the object-side surface 1041 and the image-side surface 1042 being aspheric.

The fifth lens element 1050 with positive refractive power has an object-side surface 1051 being convex in a range from the object axis 1090 to the image-side surface 1052, wherein the object-side surface 1051 and the image-side surface 1052 are aspheric, and the object-side surface 1051 has at least one inflection point.

The sixth lens element 1060 with negative refractive power has an object-side surface 1061 being convex at a paraxial region 1090, an image-side surface 1062 being concave at a paraxial region 1090, the object-side surface 1061 and the image-side surface 1062 being aspheric, and the object-side surface 1061 and the image-side surface 1062 having at least one inflection point.

The ir-cut filter assembly 1070 is made of glass and disposed between the sixth lens element 1060 and the image plane 1080 without affecting the focal length of the six-piece wide-angle lens assembly.

Further, the following table 19 and table 20 are referred to.

In a tenth embodiment, the curve equation for an aspherical surface represents the form as in the first embodiment. In addition, the definitions of the parameters in the following table are the same as those of the first embodiment, and are not repeated herein.

The following data can be derived from the coordination tables 19 and 20:

eleventh embodiment

Referring to fig. 11A and 11B, fig. 11A is a schematic diagram of a six-piece wide-angle lens assembly according to an eleventh embodiment of the invention, and fig. 11B is a graph of field curvature and distortion aberration curves of the six-piece wide-angle lens assembly according to the eleventh embodiment in order from left to right. In fig. 11A, the six-piece wide-angle lens assembly includes an aperture stop 1100 and an optical assembly, which includes, in order from an object side to an image side, a first lens element 1110, a second lens element 1120, a third lens element 1130, a fourth lens element 1140, a fifth lens element 1150, a sixth lens element 1160 and an image plane 1180, wherein six lens elements have refractive power. Diaphragm 1100 is disposed between first lens 1110 and second lens 1120.

The first lens element 1110 with negative refractive power has an object-side surface 1111 being concave at a paraxial region 1190 thereof, and an image-side surface 1112 being concave at a paraxial region 1190 thereof, and both the object-side surface 1111 and the image-side surface 1112 being aspheric.

The second lens element 1120 with positive refractive power has an object-side surface 1121 being convex at a paraxial region 1190 thereof and an image-side surface 1122 being convex at a paraxial region 1190 thereof, and both the object-side surface 1121 and the image-side surface 1122 being aspheric.

The third lens element 1130 with negative refractive power is made of plastic material, and has an object-side surface 1131 being convex at a paraxial region 1190 and an image-side surface 1132 being concave at a paraxial region 1190, wherein the object-side surface 1131 and the image-side surface 1132 are both aspheric.

The fourth lens element 1140 with positive refractive power has an object-side surface 1141 being convex at a paraxial region 1190 thereof and an image-side surface 1142 being concave at a paraxial region 1190 thereof, wherein the object-side surface 1141 and the image-side surface 1142 are aspheric.

The fifth lens element 1150 with positive refractive power is made of plastic material, and has an object-side surface 1151 being convex in a position close to the optical axis 1190 and an image-side surface 1152 being convex in a position close to the optical axis 1190, wherein the object-side surface 1151 and the image-side surface 1152 are aspheric, and the object-side surface 1151 has at least one inflection point.

The sixth lens element 1160 with negative refractive power is made of plastic material, and has an object-side surface 1161 being convex at a paraxial region 1190 and an image-side surface 1162 being concave at a paraxial region 1190, wherein the object-side surface 1161 and the image-side surface 1162 are aspheric and the object-side surface 1161 and the image-side surface 1162 have at least one inflection point.

The IR-cut filter 1170 is made of glass and disposed between the sixth lens element 1160 and the image plane 1180 without affecting the focal length of the six-piece wide-angle lens assembly.

The following table 21 and table 22 are referred to in combination.

In the eleventh embodiment, the curve equation of the aspherical surface represents the form as in the first embodiment. In addition, the definitions of the parameters in the following table are the same as those of the first embodiment, and are not repeated herein.

The following data can be derived from the coordination table 21 and the table 22:

in the six-piece wide-angle lens group provided by the invention, the material of the lens can be plastic or glass, when the material of the lens is plastic, the production cost can be effectively reduced, and when the material of the lens is glass, the degree of freedom of the configuration of the refractive power of the six-piece wide-angle lens group can be increased. In addition, the object-side surface and the image-side surface of the lenses in the six-piece wide-angle lens group can be aspheric surfaces, the aspheric surfaces can be easily made into shapes other than spherical surfaces, more control variables are obtained for reducing the aberration, and the number of the lenses is further reduced, so that the total length of the six-piece wide-angle lens group can be effectively reduced.

In the six-lens wide-angle lens assembly provided by the invention, regarding the lens with refractive power, if the lens surface is a convex surface and the position of the convex surface is not defined, the lens surface is a convex surface at a paraxial region; if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at the paraxial region.

The six-piece wide-angle lens group provided by the invention can be applied to an optical system for moving focusing according to the requirements, has the characteristics of excellent aberration correction and good imaging quality, and can be applied to electronic image systems such as 3D (three-dimensional) image acquisition, digital cameras, mobile devices, digital drawing boards or vehicle photography and the like in many aspects.

In summary, the above-mentioned embodiments are merely preferred embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A six-lens wide-angle lens assembly comprising an aperture stop and an optical group consisting of six lenses, in order from an object side to an image side:

the first lens element with negative refractive power has an object-side surface being concave at a paraxial region thereof and an image-side surface being concave at a paraxial region thereof, and at least one of the object-side surface and the image-side surface of the first lens element is aspheric;

the aperture;

the second lens element with positive refractive power has an object-side surface being convex at a paraxial region thereof, and an image-side surface being convex at a paraxial region thereof, wherein at least one of the object-side surface and the image-side surface of the second lens element is aspheric;

the third lens element with negative refractive power has an object-side surface being convex at a paraxial region thereof and an image-side surface being concave at a paraxial region thereof, and at least one of the object-side surface and the image-side surface of the third lens element is aspheric;

the fourth lens element with positive refractive power has an object-side surface being convex at a paraxial region thereof and an image-side surface being concave at a paraxial region thereof, wherein at least one of the object-side surface and the image-side surface of the fourth lens element is aspheric;

the fifth lens element with positive refractive power has an object-side surface being convex at a paraxial region thereof, and an image-side surface being convex at a paraxial region thereof, wherein at least one of the object-side surface and the image-side surface of the fifth lens element is aspheric, and at least one of the object-side surface and the image-side surface of the fifth lens element has at least one inflection point; and

the sixth lens element with negative refractive power has an object-side surface being convex at a paraxial region thereof and an image-side surface being concave at a paraxial region thereof, and at least one of the object-side surface and the image-side surface of the sixth lens element is aspheric, and at least one of the object-side surface and the image-side surface of the sixth lens element has at least one inflection point;

the thickness of the first lens element on the optical axis is CT1, the thickness of the third lens element on the optical axis is CT3, the thickness of the fourth lens element on the optical axis is CT4, the thickness of the fifth lens element on the optical axis is CT5, the thickness of the sixth lens element on the optical axis is CT6, half of the imaging height of the six-piece type wide-angle lens element set on the imaging plane is IMH, the distance from the aperture to the imaging plane on the optical axis is CTSI, and the following conditions are satisfied:

0.82< (CT4+ CT5)/(CT1+ CT3+ CT6) <1.96, 2.07< (CT1+ CT6)/CT3<5.52, and 0.92 ≦ CTSI/(IMH x 2) < 1.2.

2. The six-piece wide angle lens group of claim 1, wherein the overall focal length of the six-piece wide angle lens group is f, and the combined focal length of the fourth lens element and the fifth lens element is f45, wherein the following conditions are satisfied: 0.45< f/f45< 1.34.

3. The six-piece wide angle lens group of claim 1, wherein the combined focal length of the second, third, fourth, fifth and sixth lenses is f23456, the overall focal length of the six-piece wide angle lens group is f, and the following conditions are satisfied: 0.56< f/f23456< 1.51.

4. The set of six-piece wide-angle lenses of claim 1, wherein the third lens has a focal length of f3, and the combined focal length of the fourth lens and the fifth lens is f45, wherein the following conditions are satisfied: -3.75< f3/f45< -1.62.

5. The set of six-piece wide-angle lenses of claim 1, wherein the combined focal length of the fourth lens element and the fifth lens element is f45, the focal length of the sixth lens element is f6, and the following conditions are satisfied: -6.04< f6/f45< -0.95.

6. The set of six-piece wide-angle lens of claim 1, wherein the optical axis thickness of the fourth lens element is CT4, the optical axis thickness of the fifth lens element is CT5, and the optical axis thickness of the third lens element is CT3, wherein the following conditions are satisfied: 3.78< (CT4+ CT5)/CT3< 8.38.

7. The six-piece wide-angle lens assembly of claim 1, wherein the second lens element has an optical thickness CT2 and the third lens element has an optical thickness CT3, wherein the following conditions are satisfied: 2.41< CT2/CT3< 5.78.

8. The six-piece wide-angle lens assembly of claim 1, wherein the sixth lens element has an optical axis thickness CT6, the third lens element has an optical axis thickness CT3, and the following conditions are satisfied: 1.07< CT6/CT3< 2.86.

9. The six-piece wide-angle lens assembly of claim 1, wherein the optical thickness of the fourth lens element is CT4, the optical thickness of the fifth lens element is CT5, and the optical thickness of the first lens element is CT1, wherein the following conditions are satisfied: 1.41< (CT4+ CT5)/CT1< 7.4.

10. The six-piece wide angle lens assembly of claim 1, wherein the combined focal length of the second, third, fourth, fifth and sixth lenses is f23456, half of the image height of the six-piece wide angle lens assembly at the image plane is IMH, and the following conditions are satisfied: 0.99< IMH/f23456< 1.98.

11. The six-piece wide angle lens assembly of claim 1, wherein the overall focal length of the six-piece wide angle lens assembly is f, and half of the imaging height of the six-piece wide angle lens assembly at the imaging plane is IMH, and the following conditions are satisfied: 0.9< IMH/f < 2.69.

12. The six-piece wide-angle lens group of claim 1, wherein the distance on the optical axis from the image-side surface of the sixth lens element to the image plane is BFL, the overall focal length of the six-piece wide-angle lens group is f, and the following conditions are satisfied: 0.79< f/BFL < 2.17.