TW201910853A - Wide-angle lens - Google Patents

Abstract

A wide-angle lens assembly includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens. The first lens is a meniscus lens with negative refractive power. The second lens is with positive refractive power and includes a convex surface facing an object side. The third lens is with positive refractive power and includes a convex surface facing an image side. The fourth lens is with positive refractive power and includes a convex surface facing an object side. The fifth lens is with negative refractive power and includes a concave surface facing the object side and a convex surface facing the image side. The first lens, the second lens, the third lens, the fourth lens and the fifth lens are arranged in order from the object side to the image side along an optical axis.

Description

Wide-angle lens

The invention relates to a wide-angle lens.

In addition to the trend toward miniaturization, large field of view, and large aperture, the development trend of today's wide-angle lenses also requires the ability to resist severe environmental temperature changes with different application requirements. The conventional imaging lenses can no longer meet today's Demand requires another imaging lens with a new architecture to meet the needs of miniaturization, large field of view, large aperture and resistance to severe environmental temperature changes.

In view of this, the main purpose of the present invention is to provide a wide-angle lens with a short total lens length, a large field of view, a small aperture value, and resistance to severe environmental temperature changes, but still having good optical performance.

The wide-angle lens of the present invention includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens. The first lens has negative refractive power and is a meniscus lens. The second lens has positive refractive power and includes a convex surface facing an object side. The third lens has positive refractive power and includes a convex surface facing an image side. The fourth lens has positive refractive power and includes a convex surface facing the object side. The fifth lens has negative refractive power and includes a concave surface facing the object side and a convex surface facing the image side. The first lens, the second lens, the third lens, the fourth lens, and the fifth lens are arranged in order from the object side to the image side along an optical axis.

The wide-angle lens of the present invention includes a first lens, an aperture, a second lens, a third lens, a fourth lens, and a fifth lens. The first lens has negative refractive power and includes a concave surface facing an image side. The second lens has positive refractive power and includes a convex surface facing an object side. The third lens has positive refractive power and includes a convex surface facing the image side. The fourth lens is a biconvex lens with positive refractive power. The fifth lens has negative refractive power and includes a concave surface facing the object side and a convex surface facing the image side. The first lens, the aperture, the second lens, the third lens, the fourth lens, and the fifth lens are sequentially arranged along the optical axis from the object side to the image side.

The first lens may further include a convex surface facing the object side, the second lens may further include a convex surface facing the image side, the third lens may further include a concave surface facing the object side, and the fourth lens may further include a convex surface facing the image side.

The first lens may further include a concave surface facing the image side, the second lens may further include a concave surface facing the image side, the third lens may further include a convex surface facing the object side, and the fourth lens may further include a convex surface facing the image side.

The wide-angle lens satisfies the following conditions: Vd ₁ +Vd ₂ 90; wherein, Vd ₁ is one Abbe coefficient of the first lens, and Vd ₂ is one Abbe coefficient of the second lens.

The wide-angle lens satisfies the following conditions: Vd ₄ -Vd ₃ 20; where, Vd ₃ is one Abbe coefficient of the third lens, and Vd ₄ is one Abbe coefficient of the fourth lens.

The wide-angle lens meets the following conditions: AAG/TTL 0.55; wherein, AAG is the sum of all air distances from the first lens to an imaging plane on the optical axis, and TTL is the distance from the object side of the first lens to the imaging plane on the optical axis.

The wide-angle lens satisfies the following conditions: 0.28 BFL/TTL 0.38; wherein, BFL is a distance from the image side of the fifth lens to an imaging plane on the optical axis, and TTL is a distance from the object side of the first lens to the imaging plane on the optical axis.

The wide-angle lens satisfies the following conditions: Nd ₃ -Nd ₄ 0.23; where Nd ₃ is the refractive index of one of the third lenses, and Nd ₄ is the refractive index of one of the fourth lenses.

The wide-angle lens satisfies the following conditions: 0.9 f ₂ /f ₃ 1.3; where, f ₂ is the effective focal length of one of the second lenses, and f ₃ is the effective focal length of one of the third lenses.

The wide-angle lens satisfies the following conditions: 1.2 |f ₁ /f| 1.6; where, f ₁ is one of the effective focal lengths of the first lens, and f is one of the effective focal lengths of the wide-angle lens.

The fourth lens and the fifth lens are cemented with each other, and there is an aperture between the first lens and the second lens.

In order to make the above objects, features, and advantages of the present invention more comprehensible, preferred embodiments are described in detail below in conjunction with the accompanying drawings.

1, 2, 3, 4 ‧‧‧ wide-angle lens

L11, L21, L31, L41 ‧‧‧ first lens

L12, L22, L32, L42 ‧‧‧ second lens

L13, L23, L33, L43 ‧‧‧ third lens

L14, L24, L34, L44 ‧‧‧ fourth lens

L15, L25, L35, L45‧Fifth lens

ST1, ST2, ST3, ST4 ‧‧‧ aperture

OF1, OF2, OF3, OF4‧‧‧‧filter

OA1, OA2, OA3, OA4 ‧‧‧ optical axis

IMA1, IMA2, IMA3, IMA4 ‧‧‧ imaging surface

S11, S12, S13, S14, S15

S16, S17, S18, S19, S110

S111, S112

S21, S22, S23, S24, S25

S26, S27, S28, S29, S210

S211, S212

S31, S32, S33, S34, S35

S36, S37, S38, S39, S310

S311, S312

S41, S42, S43, S44, S45

S46, S47, S48, S49, S410

S411, S412

FIG. 1 is a schematic diagram of the lens configuration of the first embodiment of the wide-angle lens according to the present invention.

FIG. 2A is a longitudinal aberration (Longitudinal Aberration) diagram of the first embodiment of the wide-angle lens according to the present invention.

FIG. 2B is a field curvature diagram of the first embodiment of the wide-angle lens according to the present invention.

FIG. 2C is a distortion diagram of the first embodiment of the wide-angle lens according to the present invention.

FIG. 3 is a schematic diagram of the lens configuration of the second embodiment of the wide-angle lens according to the present invention.

FIG. 4A is a longitudinal aberration diagram of the second embodiment of the wide-angle lens according to the present invention.

FIG. 4B is a field curvature diagram of the second embodiment of the wide-angle lens according to the present invention.

FIG. 4C is a distortion diagram of the second embodiment of the wide-angle lens according to the present invention.

FIG. 5 is a schematic diagram of a lens configuration of a third embodiment of the wide-angle lens according to the present invention.

FIG. 6A is a longitudinal aberration diagram of the third embodiment of the wide-angle lens according to the present invention.

FIG. 6B is a field curvature diagram of the third embodiment of the wide-angle lens according to the present invention.

FIG. 6C is a distortion diagram of the third embodiment of the wide-angle lens according to the present invention.

FIG. 7 is a schematic diagram of a lens configuration of a fourth embodiment of the wide-angle lens according to the present invention.

FIG. 8A is a longitudinal aberration (Longitudinal Aberration) diagram of the fourth embodiment of the wide-angle lens according to the present invention.

FIG. 8B is a field curvature diagram of the fourth embodiment of the wide-angle lens according to the present invention.

FIG. 8C is a distortion diagram of the fourth embodiment of the wide-angle lens according to the present invention.

Please refer to FIG. 1, which is a schematic diagram of a lens configuration of a first embodiment of a wide-angle lens according to the present invention. The wide-angle lens 1 includes a first lens L11, an aperture ST1, a second lens L12, a third lens L13, a fourth lens L14, and a fifth in order from an object side to an image side along an optical axis OA1 The lens L15 and a filter OF1. When imaging, the light from the object side is finally imaged on an imaging surface IMA1.

The first lens L11 is a meniscus lens with negative refractive power and is made of glass material. Its object side S11 is convex, the image side S12 is concave, and both the object side S11 and the image side S12 are spherical surfaces.

The second lens L12 is a biconvex lens. The lens has a positive refractive power and is made of glass. The object side S14 is convex, the image side S15 is convex, and both the object side S14 and the image side S15 are spherical surfaces.

The third lens L13 is a meniscus lens with positive refractive power made of glass material, its object side S16 is concave, the image side S17 is convex, and both the object side S16 and the image side S17 are spherical surfaces.

The fourth lens L14 is a biconvex lens with positive refractive power made of glass material, its object side S18 is convex, the image side S19 is convex, and both the object side S18 and the image side S19 are spherical surfaces.

The fifth lens L15 is a meniscus lens with negative refractive power and is made of glass material. Its object side S19 is concave, the image side S110 is convex, and both the object side S19 and the image side S110 are spherical surfaces.

The fourth lens L14 and the fifth lens L15 are cemented with each other.

The object side S111 and the image side S112 of the filter OF1 are both flat.

In addition, the wide-angle lens 1 in the first embodiment satisfies at least one of the following conditions:

Where, Vd1 ₁ is one Abbe coefficient of the first lens L11, Vd1 ₂ is one Abbe coefficient of the second lens L12, Vd1 ₃ is one Abbe coefficient of the third lens L13, and Vd1 ₄ is one of the fourth lens L14 Abbe coefficient, AAG1 is the sum of all air distances from the first lens L11 to the imaging plane IMA1 on the optical axis OA1, TTL1 is the distance from the object side S11 of the first lens L11 to the imaging plane IMA1 on the optical axis OA1, BFL1 is a distance between the image side S110 of the fifth lens L15 and the imaging plane IMA1 on the optical axis OA1, Nd1 ₃ is a refractive index of the third lens L13, Nd1 ₄ is a refractive index of the fourth lens L14, and f ₁ is one effective focal length L11 of the first lens, f ₂ is the effective focal length of the second lens L12 one, f ₃ is the effective focal length of the third lens L13 one, f1 is the effective focal length of one of a wide-angle lens.

Using the above lens, aperture ST1 and the design satisfying at least one of the conditions (1) to (7), the wide-angle lens 1 can effectively increase the field of view, shorten the total lens length, effectively reduce the aperture value, and effectively correct aberrations 3. Resistant to severe environmental temperature changes.

If the value of the condition (6) f1 ₂ /f1 ₃ is greater than 1.3, the function of correcting aberrations is poor. Therefore, the value of f1 ₂ /f1 ₃ must be at least 1.3 or less, so the best effect range is 0.9 f1 ₂ /f1 ₃ 1.3, within this range, it has the best correction aberration conditions and helps to reduce sensitivity.

Table 1 is a table of related parameters of the lenses of the wide-angle lens 1 in FIG. 1. The data in Table 1 shows that the effective focal length of the wide-angle lens 1 of the first embodiment is 3.126 mm, the aperture value is 1.96, and the total lens length is 17.787 mm.

Table 2 is the parameter values in condition (1) to condition (7) and the calculated values of condition (1) to condition (7). As can be seen from Table 2, the wide-angle lens 1 of the first embodiment can satisfy the conditions (1) to Requirements of condition (7).

In addition, the optical performance of the wide-angle lens 1 of the first embodiment can also meet requirements, as can be seen from FIGS. 2A to 2C. FIG. 2A is a longitudinal aberration (Longitudinal Aberration) diagram of the wide-angle lens 1 of the first embodiment. FIG. 2B is a field curvature diagram of the wide-angle lens 1 of the first embodiment. Shown in FIG. 2C is a distortion diagram of the wide-angle lens 1 of the first embodiment.

As can be seen from FIG. 2A, the wide-angle lens 1 of the first embodiment has a longitudinal aberration value between -0.005mm and 0.026mm for light with wavelengths of 0.470μm, 0.510μm, 0.555μm, 0.610μm, and 0.650μm. between.

As can be seen from FIG. 2B, the wide-angle lens 1 of the first embodiment has a field of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm in the meridian (Tangential) direction and sagittal (Sagittal) direction. The curve is between -0.09mm and 0.03mm.

As can be seen from Figure 2C (the five lines in the figure almost coincide so that there is only one line), the wide-angle lens 1 of the first embodiment has a pair of wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, 0.650 μm The distortion produced by the light is between -54% and 0%.

It is obvious that the longitudinal aberration, field curvature, and distortion of the wide-angle lens 1 of the first embodiment can be effectively corrected, thereby obtaining better optical performance.

Please refer to FIG. 3, which is a schematic diagram of a lens configuration of a second embodiment of a wide-angle lens according to the present invention. The wide-angle lens 2 includes a first lens L21, an aperture ST2, a second lens L22, a third lens L23, a fourth lens L24, and a fifth in order from an object side to an image side along an optical axis OA2 The lens L25 and a filter OF2. When imaging, the light from the object side is finally imaged on an imaging surface IMA2.

The first lens L21 is a meniscus lens with negative refractive power and is made of glass material. Its object side S21 is convex, the image side S22 is concave, and both the object side S21 and the image side S22 are spherical surfaces.

The second lens L22 is a biconvex lens. The lens has a positive refractive power and is made of glass. The object side S24 is convex, the image side S25 is convex, and both the object side S24 and the image side S25 are spherical surfaces.

The third lens L23 is a meniscus lens with positive refractive power made of glass material. Its object side S26 is concave, the image side S27 is convex, and both the object side S26 and the image side S27 are spherical surfaces.

The fourth lens L24 is a biconvex lens with positive refractive power made of glass material, its object side S28 is convex, the image side S29 is convex, and both the object side S28 and the image side S29 are spherical surfaces.

The fifth lens L25 is a meniscus lens with negative refractive power and is made of glass material. Its object side S29 is concave, the image side S210 is convex, and both the object side S29 and the image side S210 are spherical surfaces.

The fourth lens L24 and the fifth lens L25 are cemented with each other.

The object side S211 and the image side S212 of the filter OF2 are both flat.

In addition, the wide-angle lens 2 in the second embodiment satisfies at least one of the following conditions:

The definitions of Vd2 ₁ , Vd2 ₂ , Vd2 ₃ , Vd2 ₄ , AAG2, TTL2, BFL2, Nd2 ₃ , Nd2 ₄ , f2 ₁ , f2 ₂ , f2 ₃ and f2 are the same as Vd1 ₁ , Vd1 ₂ , Vd1 in the first embodiment _The definitions of ₃ , Vd1 ₄ , AAG1, TTL1, BFL1, Nd1 ₃ , Nd1 ₄ , f1 ₁ , f1 ₂ , f1 ₃ and f1 are the same and will not be repeated here.

Using the above lens, aperture ST2 and a design that satisfies at least one of conditions (8) to (14), the wide-angle lens 2 can effectively increase the field of view, shorten the total lens length, effectively reduce the aperture value, and effectively correct aberrations 3. Resistant to severe environmental temperature changes.

If the absolute value of the condition (14) f2 ₁ /f2 is less than 1.2, the manufacturability of the lens is poor. Therefore, the absolute value of f2 ₁ /f2 must be at least greater than or equal to 1.2, so the best effect range is 1.2 |f2 ₁ /f2| 1.6, within this range, a better balance between wide-angle optical characteristics and lens manufacturability can be achieved. Among them, if the absolute value of f2 ₁ /f2 becomes larger, better lens manufacturability can be obtained. If f2 ₁ /f2 The absolute value of becomes smaller, you can get higher peripheral resolution performance.

Table 3 is a table of related parameters of the lenses of the wide-angle lens 2 in FIG. 3. The data in Table 3 shows that the effective focal length of the wide-angle lens 2 of the second embodiment is equal to 2.872 mm, the aperture value is equal to 2.0, and the total lens length is equal to 17.7 mm.

Table 4 shows the parameter values in Condition (8) to Condition (14) and the calculated values of Condition (8) to Condition (14). As can be seen from Table 4, the wide-angle lens 2 of the second embodiment can satisfy the conditions (8) to Requirements of condition (14).

In addition, the optical performance of the wide-angle lens 2 of the second embodiment can also meet requirements, as can be seen from FIGS. 4A to 4C. FIG. 4A is a longitudinal aberration (Longitudinal Aberration) diagram of the wide-angle lens 2 of the second embodiment. FIG. 4B is a field curvature diagram of the wide-angle lens 2 of the second embodiment. Shown in FIG. 4C is a distortion diagram of the wide-angle lens 2 of the second embodiment.

As can be seen from FIG. 4A, the wide-angle lens 2 of the second embodiment has a longitudinal aberration value between -0.035 mm and 0.03 mm for light rays with wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm. between.

As can be seen from FIG. 4B, the wide-angle lens 2 of the second embodiment has a field of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm in the meridian (Tangential) direction and sagittal (Sagittal) direction. The curve is between -0.08mm and 0.03mm.

As can be seen from Figure 4C (the five lines in the figure almost coincide so that there is only one line), the wide-angle lens 2 of the second embodiment has a pair of wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, 0.650 μm The distortion produced by the light is between -60% and 0%.

It is obvious that the longitudinal aberration, field curvature, and distortion of the wide-angle lens 2 of the second embodiment can be effectively corrected, thereby obtaining better optical performance.

Please refer to FIG. 5, which is a schematic diagram of a lens configuration of a third embodiment of a wide-angle lens according to the present invention. The wide-angle lens 3 includes a first lens L31, an aperture ST3, a second lens L32, a third lens L33, a fourth lens L34, and a fifth in order from an object side to an image side along an optical axis OA3 The lens L35 and a filter OF3. When imaging, the light from the object side is finally imaged on an imaging surface IMA3.

The first lens L31 is a meniscus lens with a negative refractive power and is made of glass material. The object side surface S31 is a convex surface, the image side surface S32 is a concave surface, and both the object side surface S31 and the image side surface S32 are spherical surfaces.

The second lens L32 is a biconvex lens. The lens has a positive refractive power and is made of a glass material. Its object side S34 is convex, the image side S35 is convex, and both the object side S34 and the image side S35 are spherical surfaces.

The third lens L33 is a meniscus lens with a positive refractive power and is made of glass material. The object side surface S36 is a concave surface, the image side surface S37 is a convex surface, and both the object side surface S36 and the image side surface S37 are spherical surfaces.

The fourth lens L34 is a biconvex lens with positive refractive power made of glass material. Its object side S38 is convex, the image side S39 is convex, and both the object side S38 and the image side S39 are spherical surfaces.

The fifth lens L35 is a meniscus lens with negative refractive power and is made of glass material. Its object side S39 is concave, the image side S310 is convex, and both the object side S39 and the image side S310 are spherical surfaces.

The fourth lens L34 and the fifth lens L35 are cemented with each other.

The object side S311 and the image side S312 of the filter OF3 are both flat.

In addition, the wide-angle lens 3 in the third embodiment satisfies at least one of the following conditions:

Above _{Vd3 1, Vd3 2, Vd3 3} , Vd3 4, AAG3, TTL3, BFL3, Nd3 3, Nd3 4, f3 1, f3 2, defined f3 and _{f3. 3} of the first embodiment Vd1 _1, Vd1 _2, Vd1 _The definitions of ₃ , Vd1 ₄ , AAG1, TTL1, BFL1, Nd1 ₃ , Nd1 ₄ , f1 ₁ , f1 ₂ , f1 ₃ and f1 are the same and will not be repeated here.

Using the above lens, aperture ST3 and the design that meets at least one of the conditions (15) to (21), the wide-angle lens 3 can effectively increase the field of view, shorten the total lens length, effectively reduce the aperture value, and effectively correct aberrations 3. Resistant to severe environmental temperature changes.

If the value of condition (15) Vd3 ₁ +Vd3 ₂ is less than 90, the achromatic function is poor. Therefore, the value of Vd3 ₁ +Vd3 ₂ must be at least greater than or equal to 90, so the best effect range is Vd3 ₁ +Vd3 ₂ 90, within this range has the best achromatic conditions.

Table 5 is a table of related parameters of the lenses of the wide-angle lens 3 in FIG. 5. The data in Table 5 shows that the effective focal length of the wide-angle lens 3 of the third embodiment is 3.29 mm, the aperture value is 2.0, and the total lens length is 18.173 mm.

Table 6 is the parameter values in Condition (15) to Condition (21) and the calculated values of Condition (15) to Condition (21). From Table 6, it can be seen that the wide-angle lens 3 of the third embodiment can satisfy the conditions (15) to Requirements of condition (21).

In addition, the optical performance of the wide-angle lens 3 of the third embodiment can also meet the requirements, which can be seen from FIGS. 6A to 6C. FIG. 6A is a longitudinal aberration (Longitudinal Aberration) diagram of the wide-angle lens 3 of the third embodiment. Shown in FIG. 6B is a field curvature diagram of the wide-angle lens 3 of the third embodiment. Fig. 6C is a distortion diagram of the wide-angle lens 3 of the third embodiment.

As can be seen from FIG. 6A, the wide-angle lens 3 of the third embodiment has a longitudinal aberration value between -0.005mm and 0.055mm for light with wavelengths of 0.470μm, 0.510μm, 0.555μm, 0.610μm, and 0.650μm. between.

As can be seen from FIG. 6B, the wide-angle lens 3 of the third embodiment pairs the light fields with the wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm in the tangential and sagittal directions. The curve is between -0.09mm and 0.02mm.

As can be seen from Fig. 6C (the five lines in the figure almost overlap so that there is only one line), the wide-angle lens 3 of the third embodiment has a pair of wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, 0.650 μm The distortion produced by the light is between -60% and 0%.

It is obvious that the longitudinal aberration, field curvature, and distortion of the wide-angle lens 3 of the third embodiment can be effectively corrected, thereby obtaining better optical performance.

Please refer to FIG. 7, which is a schematic diagram of a lens configuration according to a fourth embodiment of the wide-angle lens of the present invention. The wide-angle lens 4 includes a first lens L41, an aperture ST4, a second lens L42, a third lens L43, a fourth lens L44, and a fifth in order from an object side to an image side along an optical axis OA4 The lens L45 and a filter OF4. When imaging, the light from the object side is finally imaged on an imaging surface IMA4.

The first lens L41 is a meniscus lens with a negative refractive power made of glass material. Its object side S41 is convex, the image side S42 is concave, and both the object side S41 and the image side S42 are spherical surfaces.

The second lens L42 is a meniscus lens. The lens has positive refractive power and is made of glass. The object side S44 is convex, the image side S45 is concave, and both the object side S44 and the image side S45 are spherical surfaces.

The third lens L43 is a biconvex lens with positive refractive power made of glass material. The object side S46 is convex, the image side S47 is convex, and both the object side S46 and the image side S47 are spherical surfaces.

The fourth lens L44 is a biconvex lens with positive refractive power made of glass material, its object side S48 is convex, the image side S49 is convex, and both the object side S48 and the image side S49 are spherical surfaces.

The fifth lens L45 is a meniscus lens with a negative refractive power made of glass material. The object side S49 is concave, the image side S410 is convex, and both the object side S49 and the image side S410 are spherical surfaces.

The fourth lens L44 and the fifth lens L45 are cemented with each other.

The object side S411 and the image side S412 of the filter OF4 are both flat.

In addition, the wide-angle lens 4 in the fourth embodiment satisfies at least one of the following conditions:

The definitions of Vd4 ₁ , Vd4 ₂ , Vd4 ₃ , Vd4 ₄ , AAG4, TTL4, BFL4, Nd4 ₃ , Nd4 ₄ , f4 ₁ , f4 ₂ , f4 ₃ and f4 are the same as Vd1 ₁ , Vd1 ₂ , Vd1 in the first embodiment _The definitions of ₃ , Vd1 ₄ , AAG1, TTL1, BFL1, Nd1 ₃ , Nd1 ₄ , f1 ₁ , f1 ₂ , f1 ₃ and f1 are the same and will not be repeated here.

Using the above lens, aperture ST4 and the design that satisfies at least one of conditions (22) to (28), the wide-angle lens 4 can effectively increase the field of view, shorten the total lens length, effectively reduce the aperture value, and effectively correct aberrations 3. Resistant to severe environmental temperature changes.

If the value of condition (23) Vd4 ₄ -Vd4 ₃ is less than 20, the achromatic function is poor. Therefore, the value of Vd4 ₄ -Vd4 ₃ must be at least greater than or equal to 20, so the best effect range is Vd4 ₄ -Vd4 ₃ 20, within this range has the best achromatic conditions.

Table 7 is a table of related parameters of the lenses of the wide-angle lens 4 in FIG. 7. The data in Table 7 shows that the effective focal length of the wide-angle lens 4 of the fourth embodiment is 3.33 mm, the aperture value is 2.0, and the total lens length is 17.918 mm.

Table 8 shows the parameter values in Condition (22) to Condition (28) and the calculated values of Condition (22) to Condition (28). From Table 8, it can be seen that the wide-angle lens 4 of the fourth embodiment can satisfy the conditions (22) to Requirements of condition (28).

In addition, the optical performance of the wide-angle lens 4 of the fourth embodiment can also meet the requirements, as can be seen from FIGS. 8A to 8C. FIG. 8A is a longitudinal aberration (Longitudinal Aberration) diagram of the wide-angle lens 4 of the fourth embodiment. FIG. 8B shows a field curvature diagram of the wide-angle lens 4 of the fourth embodiment. Shown in FIG. 86C is a distortion diagram of the wide-angle lens 4 of the fourth embodiment.

As can be seen from FIG. 8A, the wide-angle lens 4 of the fourth embodiment has a longitudinal aberration value between -0.015mm and 0.065mm for light rays with wavelengths of 0.470μm, 0.510μm, 0.555μm, 0.610μm, 0.650μm. between.

As can be seen from FIG. 8B, the wide-angle lens 4 of the fourth embodiment has a field of light at wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm in the tangential direction and sagittal direction. The curve is between -0.03mm and 0.10mm.

It can be seen from Figure 8C (the five lines in the figure almost coincide so that there appears to be only one line), the wide-angle lens 4 of the fourth embodiment has a pair of wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, 0.650 μm The distortion produced by the light is between -67% and 0%.

It is obvious that the longitudinal aberration, field curvature, and distortion of the wide-angle lens 4 of the fourth embodiment can be effectively corrected, thereby obtaining better optical performance.

The formula in accordance with the present invention f ₂ /f ₃ 1.3, 1.2 |f ₁ /f| 1.6, Vd ₁ +Vd ₂ 90、Vd ₄ -Vd ₃ 20 is the center, and the numerical value of the embodiment of the present invention also falls within the range of the remaining formulas. Formula 0.9 f ₂ /f ₃ 1.3, can help the overall aberration correction performance. Formula 1.2 |f ₁ /f| 1.6, can make the balanced performance between wide-angle optical characteristics and lens manufacturability helpful. Formula Vd ₁ +Vd ₂ 90, can make achromatic performance better, the best suitable range is 118 Vd ₁ +Vd ₂ 90. Formula Vd ₄ -Vd ₃ 20, can make achromatic performance better, the best suitable range is 35 Vd ₄ -Vd ₃ 20.

Although the present invention has been disclosed as above in an embodiment, it is not intended to limit the present invention. Anyone who is familiar with this art can make various changes and modifications within the spirit and scope of the present invention, so the protection of the present invention The scope shall be determined by the scope of the attached patent application.

Claims (10)

A wide-angle lens includes: a first lens with negative refractive power, the first lens is a meniscus lens; a second lens with positive refractive power, the second lens includes a convex surface facing an object side; and a third lens with positive refractive power , The third lens includes a convex surface facing an image side; a fourth lens has positive refractive power, the fourth lens includes a convex surface facing the object side; and a fifth lens has negative refractive power, the fifth lens includes a concave surface facing The object side and a convex surface face the image side; wherein the first lens, the second lens, the third lens, the fourth lens, and the fifth lens follow the optical axis from the object side to the image side Ordered. The wide-angle lens as described in item 1 of the patent scope, wherein the first lens further includes a convex surface facing the object side, the second lens further includes a convex surface facing the image side, and the third lens further includes a concave surface facing the object On the side, the fourth lens further includes a convex surface facing the image side. The wide-angle lens as described in item 1 of the patent application scope, wherein the first lens further includes a concave surface facing the image side, the second lens further includes a concave surface facing the image side, and the third lens further includes a convex surface facing the object On the side, the fourth lens further includes a convex surface facing the image side. The wide-angle lens as described in item 2 or item 3 of the patent application scope, wherein the wide-angle lens satisfies the following conditions: Vd ₁ +Vd ₂ 90; Vd ₄ -Vd ₃ 20; where, Vd _{1 is} one of the Abbe coefficients of the first lens, Vd _{2 is} one of the Abbe coefficients of the second lens, Vd _{3 is} one of the Abbe coefficients of the third lens, and Vd _{4 is} the fourth lens One Abbe coefficient. The wide-angle lens as described in item 2 or item 3 of the patent application scope, where the wide-angle lens meets the following conditions: AAG/TTL 0.55; wherein, AAG is the sum of all air distances from the first lens to an imaging plane on the optical axis, and TTL is a distance from the object side of the first lens to the imaging plane on the optical axis. The wide-angle lens as described in item 5 of the patent application scope, wherein the wide-angle lens satisfies the following conditions: 0.28 BFL/TTL 0.38; wherein, BFL is a distance from an image side of the fifth lens to an imaging plane on the optical axis, and TTL is a distance from an object side of the first lens to the imaging plane on the optical axis. The wide-angle lens as described in item 2 or item 3 of the patent application scope, wherein the wide-angle lens satisfies the following conditions: Nd ₃ -Nd ₄ 0.23; wherein, Nd _{3 is a} refractive index of the third lens, and Nd _{4 is a} refractive index of the fourth lens. The wide-angle lens as described in item 2 or item 3 of the patent application scope, wherein the wide-angle lens satisfies the following conditions: 0.9 f ₂ /f ₃ 1.3; where, f _{2 is} one of the effective focal length of the second lens, and f _{3 is} one of the effective focal length of the third lens. The wide-angle lens as described in item 8 of the patent application scope, wherein the wide-angle lens satisfies the following conditions: 1.2 |f ₁ /f| 1.6; where f _{1 is} one of the effective focal lengths of the first lens, and f is one of the effective focal lengths of the wide-angle lens. The wide-angle lens as described in item 2 or 3 of the patent application scope, wherein the fourth lens and the fifth lens are cemented with each other, and an aperture is formed between the first lens and the second lens.