TWI662293B - Five-piece optical lens system with a wide field of view - Google Patents

Abstract

The present invention is a five-piece wide-angle lens group, which sequentially includes: a first lens having a negative refractive power; an aperture; a second lens having a positive refractive power; a third lens having a A negative refractive power; a fourth lens having a positive refractive power; and a fifth lens having a negative refractive power. Accordingly, the present invention provides a five-piece wide-angle lens group with enhanced picture angle, high resolution, short lens length, and small distortion.

Description

Five-piece wide-angle lens group

The invention relates to a five-piece wide-angle lens group, in particular to a miniaturized five-piece wide-angle lens group applied to electronic products.

With the rise of electronic products with photographic functions, the demand for optical systems is increasing. During shooting, in order to obtain a wider shooting range, the angle of view of the lens needs to meet certain requirements, so the requirements for the shooting angle and quality of the lens are becoming stricter. Generally, the angle of view (FOV of the lens) of the lens is designed to be 50 degrees to 60 degrees. If it exceeds the above designed angle, not only the aberration is large, but the lens design is also more complicated. It is known that US 8335043 and US 8576497 use 2 lens groups and 5 to 6 lenses to achieve a large angle. However, the distortion is too large. For example, US 8593737, US 8576497, and US 8395853, although they can achieve a large angle, But the total length (TL) of its lens group is too long.

Therefore, how to develop a miniaturized five-piece wide-angle lens group, which can be arranged in addition to electronic products such as lenses for digital cameras, lenses for web cameras, or mobile phone lenses, and has a larger angle of view The effect of reducing aberrations to reduce the complexity of lens design is the motivation for the development of the present invention.

The purpose of the present invention is to provide a five-piece wide-angle lens group, in particular to a five-piece wide-angle lens group with enhanced picture angle, high resolution, short lens length, and small distortion.

The reason is that, in order to achieve the foregoing object, a five-piece wide-angle lens group according to the present invention includes, in order from the object side to the image side, a first lens having a negative refractive power, and an object side surface near the optical axis. It is convex, its image side surface is concave near the optical axis, at least one of its object side surface and image side surface is aspheric; an aperture; and a second lens has a positive refractive power, and its object side surface is near the optical axis. It is convex, and its image side surface is convex near the optical axis, and at least one of its object side surface and image side surface is aspherical; a third lens has a negative refractive power, and its object side surface is convex near the optical axis. Its image-side surface is concave at the near-light axis, and at least one of its object-side surface and image-side surface is aspheric; a fourth lens has a positive refractive power, and its object-side surface is convex at the near-optical axis, and its image side The surface near the optical axis is convex, and at least one of the object-side surface and the image-side surface is aspherical; and a fifth lens has a negative refractive power, and the image-side surface thereof is concave at the near-light axis, and the object-side surface and At least one surface of the image side surface is aspheric, And at least one surface of the image surface-side surface has at least one inflection point.

Preferably, the focal length of the first lens is f1, and the focal length of the second lens is f2, and the following conditions are satisfied: -2.2 <f1 / f2 <-1.45. Therefore, the configuration of the refractive power of the first lens and the second lens is more appropriate, which can help to obtain a wide picture angle (field of view angle) and reduce excessive increase of system aberration.

Preferably, the focal length of the second lens is f2, and the focal length of the third lens is f3, and the following conditions are satisfied: -0.6 <f2 / f3 <-0.3. Thereby, the configuration of the refractive power of the second lens and the third lens is relatively balanced, which contributes to correction of aberrations and reduction of sensitivity.

Preferably, the focal length of the third lens is f3, and the focal length of the fourth lens is f4, and the following conditions are satisfied: -2.1 <f3 / f4 <-1.0. Therefore, it is beneficial to ensure a negative-to-positive telephoto structure formed by the third lens and the fourth lens, and the total optical length of the system can be effectively reduced.

Preferably, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the following conditions are satisfied: -1.2 <f4 / f5 <-0.7. This can make the configuration of the refractive power of the rear group lens system more balanced, which is beneficial to the reduction of system sensitivity and the correction of high-order aberrations.

Preferably, the focal length of the first lens is f1, and the focal length of the third lens is f3, and the following conditions are satisfied: 0.55 <f1 / f3 <1.0. Thereby, the refractive power of the first lens is effectively distributed, and the sensitivity of the five-piece wide-angle lens group is reduced.

Preferably, the focal length of the second lens is f2, and the focal length of the fourth lens is f4, and the following conditions are satisfied: 0.4 <f2 / f4 <0.95. In this way, the system's negative inflection force distribution is more appropriate, which is conducive to correcting system aberrations and improving system imaging quality.

Preferably, the focal length of the third lens is f3, and the focal length of the fifth lens is f5, and the following conditions are satisfied: 1.0 <f3 / f5 <1.8. This helps shorten the overall length of the five-piece wide-angle lens group and maintains its miniaturization.

Preferably, the focal length of the first lens is f1, and the combined focal length of the second lens and the third lens is f23, and the following conditions are satisfied: -1.5 <f1 / f23 <-0.95. Therefore, when f1 / f23 satisfies the above conditions, the five-piece wide-angle lens group can obtain a wide picture angle (field of view), and its resolution capability is significantly improved.

Preferably, the combined focal length of the second lens and the third lens is f23, the combined focal length of the fourth lens and the fifth lens is f45, and the following conditions are satisfied: 0.2 <f23 / f45 <0.8. When f23 / f45 satisfies the aforementioned relationship, the five-piece wide-angle lens group can have a large picture angle, a high number of pictures, and a low lens height, and at the same time, the resolution can be significantly improved. On the contrary, if it exceeds the optical data value Range, it will cause problems with the performance, resolution, and insufficient yield of the five-piece wide-angle lens group.

Preferably, a composite focal length of the first lens and the second lens is f12, a composite focal length of the third lens and the fourth lens is f34, and the following conditions are satisfied: 0.15 <f12 / f34 <0.75. Thereby, it can be beneficial to obtain a wide picture angle (field of view angle) and effectively correct image plane curvature.

Preferably, a combined focal length of the third lens and the fourth lens is f34, a focal length of the fifth lens is f5, and the following conditions are satisfied: -2.6 <f34 / f5 <-1.2. When f34 / f5 satisfies the aforementioned relationship, the five-piece wide-angle lens group can have a large picture angle, a high number of pictures, and a low lens height, and at the same time, the resolution can be significantly improved. On the contrary, if it exceeds the optical data Range, it will cause problems with the performance, resolution, and insufficient yield of the five-piece wide-angle lens group.

Preferably, the focal length of the first lens is f1, and the combined focal length of the second lens, the third lens, and the fourth lens is f234, and the following conditions are satisfied: -2.4 <f1 / f234 <-1.3. With proper configuration of the inflection force, it helps to reduce the occurrence of spherical aberration and astigmatism.

Preferably, a combined focal length of the second lens, a third lens, and a fourth lens is f234, a focal length of the fifth lens is f5, and the following conditions are satisfied: -0.8 <f234 / f5 <-0.35. With proper configuration of the inflection force, it helps to reduce the occurrence of spherical aberration and astigmatism.

Preferably, the combined focal length of the first lens, the second lens, and the third lens is f123, and the focal length of the fourth lens is f4, and the following conditions are satisfied: 1.65 <f123 / f4 <3.0. With proper configuration of the inflection force, it helps to reduce the occurrence of spherical aberration and astigmatism.

Preferably, the combined focal length of the first lens, the second lens, and the third lens is f123, the combined focal length of the fourth lens and the fifth lens is f45, and the following conditions are satisfied: 0.65 <f123 / f45 <1.8. With proper configuration of the inflection force, it helps to reduce the occurrence of spherical aberration and astigmatism.

Preferably, the dispersion coefficient of the second lens is V2, and the dispersion coefficient of the third lens is V3, and the following conditions are satisfied: 30 <V2-V3 <42. Thereby, the chromatic aberration of the five-piece wide-angle lens group is effectively reduced.

Preferably, the dispersion coefficient of the fourth lens is V4, and the dispersion coefficient of the fifth lens is V5, and the following conditions are satisfied: 30 <V4-V5 <42. Thereby, the chromatic aberration of the five-piece wide-angle lens group is effectively reduced.

Preferably, the overall focal length of the five-piece wide-angle lens group is f, and the distance from the object-side surface of the first lens to the imaging surface on the optical axis is TL, and the following conditions are satisfied: 0.25 <f / TL <0.6 . Thereby, it can be beneficial to obtain a wide picture angle (field of view) and to maintain the miniaturization of the five-piece wide-angle lens group for mounting on thin and light electronic products.

Preferably, the focal length of the first lens is f1, and the combined focal length of the second lens, the third lens, the fourth lens, and the fifth lens is f2345, and the following conditions are satisfied: -2.7 <f1 / f2345 <-1.6 . With this, when f1 / f2345 satisfies the aforementioned relationship, the five-piece wide-angle lens group can have a large picture angle, and at the same time, the resolution can be significantly improved. Conversely, if it exceeds the above-mentioned optical data range, it will cause The five-piece wide-angle lens group has problems such as low performance, low resolution, and insufficient yield.

Regarding the technology, means, and other effects adopted by the present invention to achieve the foregoing objectives, three preferred feasible embodiments are described in detail below with reference to the drawings.

100, 200, 300‧‧‧ aperture

110, 210, 310‧‧‧ first lens

111, 211, 311‧‧‧ object-side surface

112, 212, 312‧‧‧ image side surface

120, 220, 320‧‧‧Second lens

121, 221, 321‧‧‧ object-side surface

122, 222, 322‧‧‧ image side surface

130, 230, 330‧‧‧ Third lens

131, 231, 331‧‧‧ object-side surface

132, 232, 332‧‧‧‧ image side surface

140, 240, 340‧‧‧ Fourth lens

141, 241, 341‧‧‧ object-side surface

142, 242, 342‧‧‧ image side surface

150, 250, 350‧‧‧ fifth lens

151, 251, 351‧‧‧ object-side surface

152, 252, 352‧‧‧ image side surface

170, 270, 370‧‧‧IR filter element

180, 280, 380‧‧‧ imaging surface

190, 290, 390‧‧‧ Optical axis

f‧‧‧Focal length of five-element wide-angle lens group

Aperture value of Fno‧‧‧ five-element wide-angle lens group

Maximum field of view in FOV‧‧‧ five-element wide-angle lens group

f1‧‧‧ focal length of the first lens

f2‧‧‧ focal length of the second lens

f3‧‧‧ focal length of the third lens

f4‧‧‧ focal length of the fourth lens

f5‧‧‧ the focal length of the fifth lens

f12‧‧‧The combined focal length of the first lens and the second lens

f23‧‧‧The combined focal length of the second lens and the third lens

f34‧‧‧The combined focal length of the third lens and the fourth lens

f45‧‧‧The combined focal length of the fourth lens and the fifth lens

f123‧‧‧The combined focal length of the first lens, the second lens and the third lens

f234‧‧‧The combined focal length of the second, third, and fourth lenses

f2345‧‧‧The combined focal lengths of the second, third, fourth, and fifth lenses

V2‧‧‧The dispersion coefficient of the second lens

V3‧‧‧ Dispersion coefficient of the third lens

V4‧‧‧ Dispersion coefficient of the fourth lens

V5‧‧‧ fifth lens dispersion coefficient

TL‧‧‧The distance from the object side surface of the first lens to the imaging plane on the optical axis

FIG. 1A is a schematic diagram of a five-piece wide-angle lens group according to the first embodiment of the present invention.

FIG. 1B is a curve diagram of the curvature and distortion of the image plane of the five-piece wide-angle lens group of the first embodiment in order from left to right.

FIG. 2A is a schematic diagram of a five-piece wide-angle lens group according to a second embodiment of the present invention.

FIG. 2B is a curve diagram of the curvature and distortion of the image plane of the five-piece wide-angle lens group according to the second embodiment in order from left to right.

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

FIG. 3B is a curve diagram of the curvature and distortion of the image plane of the five-piece wide-angle lens group according to the third embodiment in order from left to right.

<First Embodiment>

Please refer to FIG. 1A and FIG. 1B. FIG. 1A shows a schematic diagram of a five-piece wide-angle lens group according to the first embodiment of the present invention. FIG. Curved and distorted narrowing of the image plane. It can be seen from FIG. 1A that the five-piece wide-angle lens group includes an aperture 100 and an optical group. The optical group sequentially includes the first lens 110, the second lens 120, the third lens 130, and the fourth lens from the object side to the image side. The lens 140, the fifth lens 150, the infrared filter element 170, and the imaging surface 180. Among the five-piece wide-angle lens group, five lenses have refractive power. The diaphragm 100 is disposed between the image-side surface 112 of the first lens 110 and the image-side surface 122 of the second lens 120.

The first lens 110 has a negative refractive power and is made of plastic. The object-side surface 111 is convex near the optical axis 190, the image-side surface 112 is concave near the optical axis 190, and the object-side surface 111 and the image side The surfaces 112 are all aspheric.

The second lens 120 has a positive refractive power and is made of plastic. The object-side surface 121 of the second lens 120 is convex near the optical axis 190, the image-side surface 122 of the second lens 120 is convex near the optical axis 190, and the object-side surface 121 and the image side The surfaces 122 are all aspheric.

The third lens 130 has a negative refractive power and is made of plastic. The object-side surface 131 is convex near the optical axis 190, the image-side surface 132 is concave near the optical axis 190, and the object-side surface 131 and the image side The surfaces 132 are all aspherical.

The fourth lens 140 has a positive refractive power and is made of plastic. The object-side surface 141 is convex near the optical axis 190, the image-side surface 142 is convex near the optical axis 190, and the object-side surface 141 and the image side The surfaces 142 are all aspheric.

The fifth lens 150 has a negative refractive power and is made of plastic. Its object-side surface 151 is convex near the optical axis 190, its image-side surface 152 is concave near the optical axis 190, and the object-side surface 151 and the image side The surface 152 is an aspheric surface, and at least one surface of the object-side surface 151 and the image-side surface 152 has at least one inflection point.

The infrared filter element 170 is made of glass and is disposed between the fifth lens 150 and the imaging surface 180 without affecting the focal length of the five-piece wide-angle lens group.

The aspheric curve equations of the above lenses are expressed as follows:

Where z is the position value with the surface apex as the reference at the height h along the direction of the optical axis 190; c is the curvature of the lens surface near the optical axis 190, and is the inverse of the radius of curvature (R) (c = 1 / R) , R is the radius of curvature of the lens surface near the optical axis 190, h is the vertical distance of the lens surface from the optical axis 190, k is the conic constant, and A, B, C, D, E, G, ... ... is a higher-order aspheric coefficient.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the five-piece wide-angle lens group is f, the aperture value (f-number) of the five-piece wide-angle lens group is Fno. The field angle (picture angle) is FOV, and its values are as follows: f = 1.920 (mm); Fno = 2.2; and FOV = 120 (degrees).

In the five-piece wide-angle lens group of the first embodiment, the focal length of the first lens 110 is f1, and the focal length of the second lens 120 is f2, and the following conditions are satisfied: f1 / f2 = -1.684.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the second lens 120 is f2, and the focal length of the third lens 130 is f3, and the following conditions are satisfied: f2 / f3 = -0.457.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the third lens 130 is f3, and the focal length of the fourth lens 140 is f4, and the following conditions are satisfied: f3 / f4 = -1.342.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the fourth lens 140 is f4, and the focal length of the fifth lens 150 is f5, and the following conditions are satisfied: f4 / f5 = -0.894.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the first lens 110 is f1, and the focal length of the third lens 130 is f3, and the following conditions are satisfied: f1 / f3 = 0.770.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the second lens 120 is f2, and the focal length of the fourth lens 140 is f4, and the following conditions are satisfied: f2 / f4 = 0.613.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the third lens 130 is f3, and the focal length of the fifth lens 150 is f5, and the following conditions are satisfied: f3 / f5 = 1.201.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the first lens 110 is f1, and the combined focal length of the second lens 120 and the third lens 130 is f23, and the following conditions are satisfied: f1 / f23 = -1.186 .

In the five-piece wide-angle lens group of the first embodiment, the combined focal length of the second lens 120 and the third lens 130 is f23, the combined focal distance of the fourth lens 140 and the fifth lens 150 is f45, and the following conditions are satisfied: f23 / f45 = 0.441.

In the five-piece wide-angle lens group of the first embodiment, the combined focal length of the first lens 110 and the second lens 120 is f12, the combined focal distance of the third lens 130 and the fourth lens 140 is f34, and the following conditions are satisfied: f12 / f34 = 0.290.

In the five-piece wide-angle lens group of the first embodiment, the combined focal length of the third lens 130 and the fourth lens 140 is f34, the focal length of the fifth lens 150 is f5, and the following conditions are satisfied: f34 / f5 = -2.284 .

In the five-piece wide-angle lens group of the first embodiment, the focal length of the first lens is f1, and the combined focal length of the second lens 120, the third lens 130, and the fourth lens 140 is f234, and the following conditions are satisfied: f1 / f234 = -1.638.

In the five-piece wide-angle lens group of the first embodiment, the combined focal length of the second lens 120, the third lens 130, and the fourth lens 140 is f234, the focal length of the fifth lens 150 is f5, and the following conditions are satisfied: f234 /f5=-0.564.

In the five-piece wide-angle lens group of the first embodiment, the combined focal length of the first lens 110, the second lens 120, and the third lens 130 is f123, the focal length of the fourth lens 140 is f4, and the following conditions are satisfied: f123 /f4=1.969.

In the five-piece wide-angle lens group of the first embodiment, the combined focal length of the first lens 110, the second lens 120, and the third lens 130 is f123, and the combined focal length of the fourth lens 140 and the fifth lens 150 is f45. And meet the following conditions: f123 / f45 = 0.996.

In the five-piece wide-angle lens group of the first embodiment, the focal length of the first lens 110 is f1, and the combined focal length of the second lens 120, the third lens 130, the fourth lens 140, and the fifth lens 150 is f2345, and The following conditions are satisfied: f1 / f2345 = -1.889.

In the five-piece wide-angle lens group of the first embodiment, the dispersion coefficient of the second lens 120 is V2, and the dispersion coefficient of the third lens 130 is V3, and the following conditions are satisfied: V2-V3 = 34.60.

In the five-piece wide-angle lens group of the first embodiment, the dispersion coefficient of the fourth lens 140 is V4, and the dispersion coefficient of the fifth lens 150 is V5, and the following conditions are satisfied: V4-V5 = 34.60.

In the five-piece wide-angle lens group of the first embodiment, the overall focal length of the five-piece wide-angle lens group is f, and the distance from the object-side surface 111 to the imaging surface 180 of the first lens 110 on the optical axis 190 is TL, And meet the following conditions: f / TL = 0.386.

Refer to Tables 1 and 2 below for further cooperation.

Table 1 is the detailed structural data of the first embodiment of FIG. 1A, where the units of the radius of curvature, thickness, and focal length are mm, and the surfaces 0-15 sequentially indicate the surface from the object side to the image side. Table 2 is the first embodiment The aspherical data in K, where k represents the cone coefficient in the aspheric curve equation, and A, B, C, D, E, F, ... are higher-order aspheric coefficients. In addition, the tables of the following embodiments are schematic diagrams corresponding to the embodiments and the curve curves of the curvature and distortion of the image plane. The definitions of the data in the tables are the same as the definitions in Tables 1 and 2 of the first embodiment. Add more details.

<Second Embodiment>

Please refer to FIG. 2A and FIG. 2B. FIG. 2A shows a schematic diagram of a five-piece wide-angle lens group according to a second embodiment of the present invention. FIG. 2B is a five-piece wide-angle lens group of the second embodiment in order from left to right. Curved and distorted narrowing of the image plane. It can be seen from FIG. 2A that the five-piece wide-angle lens group includes an aperture 200 and an optical group, and the optical group sequentially includes a first lens 210, a second lens 220, a third lens 230, and a fourth lens from the object side to the image side. The lens 240, the fifth lens 250, the infrared filter element 270, and the imaging surface 280. Among the five-piece wide-angle lens group, five lenses have refractive power. The aperture 200 is disposed between the image-side surface 212 of the first lens 210 and the image-side surface 222 of the second lens 220.

The first lens 210 has a negative refractive power and is made of plastic. The object-side surface 211 is convex near the optical axis 290, the image-side surface 212 is concave near the optical axis 290, and the object-side surface 211 and the image side The surfaces 212 are all aspheric.

The second lens 220 has a positive refractive power and is made of plastic. The object-side surface 221 is convex near the optical axis 290, and its image-side surface 222 is convex near the optical axis 290. The object-side surface 221 and the image side The surfaces 222 are all aspheric.

The third lens 230 has a negative refractive power and is made of plastic. The object-side surface 231 of the third lens 230 is convex near the optical axis 290, and the image-side surface 232 of the third lens 230 is concave near the optical axis 290. The surfaces 232 are all aspherical.

The fourth lens 240 has positive refractive power and is made of plastic. The object-side surface 241 is convex near the optical axis 290, and the image-side surface 242 is convex near the optical axis 290. The object-side surface 241 and the image The side surfaces 242 are all aspheric.

The fifth lens 250 has a negative refractive power and is made of plastic. The object-side surface 251 of the fifth lens 250 is concave near the optical axis 290, the image-side surface 252 of the fifth lens 250 is concave near the optical axis 290, and the object-side surface 251 and the image side The surfaces 252 are all aspheric, and at least one surface of the object-side surface 251 and the image-side surface 252 has at least one inflection point.

The infrared filter element 270 is made of glass and is disposed between the fifth lens 250 and the imaging surface 280 without affecting the focal length of the five-piece wide-angle lens group.

Refer to Table 3 and Table 4 below for further cooperation.

In the second embodiment, the aspherical curve equation is expressed as the first embodiment. In addition, the definitions of the parameters in the following table are the same as those in the first embodiment, and will not be repeated here.

With Table 3 and Table 4, the following data can be calculated:

<Third Embodiment>

Please refer to FIGS. 3A and 3B. FIG. 3A is a schematic diagram of a five-piece wide-angle lens group according to a third embodiment of the present invention. FIG. 3B is a five-piece wide-angle lens group of the third embodiment in order from left to right. Curved and distorted narrowing of the image plane. It can be seen from FIG. 3A that the five-piece wide-angle lens system includes one Aperture 300 and an optical group, the optical group includes a first lens 310, a second lens 320, a third lens 330, a fourth lens 340, a fifth lens 350, and an infrared filter element in order from the object side to the image side. 370, and imaging surface 380, wherein the five lenses with refractive power in the five-piece wide-angle lens group are five. The aperture 300 is disposed between the image-side surface 312 of the first lens 310 and the image-side surface 322 of the second lens 320.

The first lens 310 has a negative refractive power and is made of plastic. The object-side surface 311 is convex near the optical axis 390, the image-side surface 312 is concave near the optical axis 390, and the object-side surface 311 and the image side The surfaces 312 are all aspheric.

The second lens 320 has a positive refractive power and is made of plastic. The object-side surface 321 is convex near the optical axis 390, and its image-side surface 322 is convex near the optical axis 390. The object-side surface 321 and the image side The surfaces 322 are all aspheric.

The third lens 330 has a negative refractive power and is made of plastic. Its object-side surface 331 is convex near the optical axis 390, its image-side surface 332 is concave near the optical axis 390, and the object-side surface 331 and the image side The surfaces 332 are all aspherical.

The fourth lens 340 has a positive refractive power and is made of plastic. The object-side surface 341 is convex near the optical axis 390, the image-side surface 342 is convex near the optical axis 390, and the object-side surface 341 and the image side The surfaces 342 are all aspheric.

The fifth lens 350 has a negative refractive power and is made of plastic. Its object-side surface 351 is convex near the optical axis 390, its image-side surface 352 is concave near the optical axis 390, and the object-side surface 351 and the image side The surface 352 is an aspheric surface, and at least one surface of the object-side surface 351 and the image-side surface 352 has at least one inflection point.

Refer to Table 5 and Table 6 below for further cooperation.

In the third embodiment, the aspherical curve equation is expressed as the first embodiment. In addition, the definitions of the parameters in the following table are the same as those in the first embodiment, and will not be repeated here.

With Table 5 and Table 6, the following data can be calculated:

In the five-piece wide-angle lens group provided by the present 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. When the material of the lens is glass, the inflection of the five-piece wide-angle lens group can be increased. Degree of freedom in force configuration. In addition, the object-side surface and image-side surface of the lens in the five-piece wide-angle lens group can be aspheric, and the aspheric surface can be easily made into a shape other than a spherical surface, and more control variables are obtained to reduce aberrations and further reduce the lens. The number used can therefore effectively reduce the total length of the five-piece wide-angle lens group of the present invention.

In the five-piece wide-angle lens group provided by the present invention, in the case of a lens having a refractive power, if the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at the near optical axis; if When the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at the near optical axis.

The five-piece wide-angle lens group provided by the present invention can be more applied to the optical system of mobile focusing as required, and has both the characteristics of excellent aberration correction and good imaging quality. It can be applied to 3D (three-dimensional) image capture, digital Electronic imaging systems such as cameras, mobile devices, digital tablets or car photography in.

In summary, the above-mentioned embodiments and drawings are only preferred embodiments of the present invention. When the scope of implementation of the present invention cannot be limited by this, that is, all equal changes and modifications made in accordance with the scope of the patent application of the present invention, It should be within the scope of the invention patent.

Claims (19)

A five-piece wide-angle lens group includes sequentially from the object side to the image side: a first lens having a negative refractive power, the object side surface of which is near the optical axis is convex, and the image side surface of which is near the optical axis is concave, At least one of the object-side surface and the image-side surface is aspherical; an aperture; and a second lens having a positive refractive power, the object-side surface is convex near the optical axis, and the image-side surface is convex near the optical axis. At least one of the object-side surface and the image-side surface is aspherical; a third lens has a negative refractive power, and the object-side surface is convex near the optical axis, and the image-side surface is concave near the optical axis, and its object side At least one of the surface and the image-side surface is aspherical; a fourth lens has a positive refractive power, and its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis, and its object-side surface and image At least one surface of the side surface is aspherical; and a fifth lens having a negative refractive power, the image side surface of which is near the optical axis is concave, at least one of the object-side surface and the image-side surface is aspherical, and the object-side surface And at least one surface of the image side surface has at least one inflection point Wherein the focal length of the first lens is f1, a focal length of the second lens is f2, and the following relationship is satisfied: -2.2 <f1 / f2 <-1.45. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the second lens is f2, and the focal length of the third lens is f3, and the following conditions are satisfied: -0.6 <f2 / f3 <-0.3. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the third lens is f3, and the focal length of the fourth lens is f4, and the following conditions are satisfied: -2.1 <f3 / f4 <-1.0. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the following conditions are satisfied: -1.2 <f4 / f5 <-0.7. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the first lens is f1, and the focal length of the third lens is f3, and the following conditions are satisfied: 0.55 <f1 / f3 <1.0. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the second lens is f2, and the focal length of the fourth lens is f4, and the following conditions are satisfied: 0.4 <f2 / f4 <0.95. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the third lens is f3, and the focal length of the fifth lens is f5, and the following conditions are satisfied: 1.0 <f3 / f5 <1.8. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the first lens is f1, and the combined focal length of the second lens and the third lens is f23, and the following conditions are satisfied: -1.5 <f1 / f23 < -0.95. The five-piece wide-angle lens group according to claim 1, wherein the combined focal distance of the second lens and the third lens is f23, the combined focal distance of the fourth lens and the fifth lens is f45, and the following conditions are satisfied: 0.2 < f23 / f45 <0.8. The five-piece wide-angle lens group according to claim 1, wherein the combined focal length of the first lens and the second lens is f12, the combined focal distance of the third lens and the fourth lens is f34, and the following conditions are satisfied: 0.15 < f12 / f34 <0.75. The five-piece wide-angle lens group according to claim 1, wherein the combined focal length of the third lens and the fourth lens is f34, the focal length of the fifth lens is f5, and the following conditions are satisfied: -2.6 <f34 / f5 < -1.2. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the first lens is f1, and the combined focal length of the second lens, the third lens, and the fourth lens is f234, and the following conditions are satisfied: -2.4 < f1 / f234 <-1.3. The five-piece wide-angle lens group according to claim 1, wherein the combined focal length of the second lens, the third lens, and the fourth lens is f234, the focal length of the fifth lens is f5, and the following conditions are satisfied: -0.8 < f234 / f5 <-0.35. The five-piece wide-angle lens group according to claim 1, wherein the combined focal length of the first lens, the second lens, and the third lens is f123, the focal length of the fourth lens is f4, and the following conditions are satisfied: 1.65 <f123 /f4<3.0. The five-piece wide-angle lens group according to claim 1, wherein the combined focal distance of the first lens, the second lens, and the third lens is f123, and the combined focal distance of the fourth lens and the fifth lens is f45, and satisfies the following Conditions: 0.65 <f123 / f45 <1.8. The five-piece wide-angle lens group according to claim 1, wherein the dispersion coefficient of the second lens is V2, and the dispersion coefficient of the third lens is V3, and the following conditions are satisfied: 30 <V2-V3 <42. The five-piece wide-angle lens group according to claim 1, wherein the dispersion coefficient of the fourth lens is V4, and the dispersion coefficient of the fifth lens is V5, and the following conditions are satisfied: 30 <V4-V5 <42. The five-piece wide-angle lens group according to claim 1, wherein the overall focal length of the five-piece wide-angle lens group is f, and the distance from the object-side surface of the first lens to the imaging plane on the optical axis is TL, and satisfies The following conditions: 0.25 <f / TL <0.6. The five-piece wide-angle lens group according to claim 1, wherein the focal length of the first lens is f1, and the combined focal length of the second lens, the third lens, the fourth lens, and the fifth lens is f2345, and the following conditions are satisfied: : -2.7 <f1 / f2345 <-1.6.