wide-angle lens

Abstract

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

Description

Technical Field

[0001] This invention relates to a wide-angle lens. Background Technology

[0002] The current trend in wide-angle lens development is not only towards a larger field of view, but also the need for high resolution to meet the demands of different applications. Existing wide-angle lenses can no longer meet current needs, and a new architecture is required to simultaneously satisfy the requirements of a large field of view and high resolution. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a wide-angle lens that has a large field of view and high resolution, while still having good optical performance, in order to address the shortcomings of existing wide-angle lenses that cannot simultaneously meet the requirements of a large field of view and high resolution.

[0004] The technical solution adopted by this invention to solve its technical problem is to provide a wide-angle lens comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens. The first lens has negative refractive power and is a meniscus lens. The second lens has positive refractive power and is also a meniscus lens. The third lens has refractive power. The fourth lens has negative refractive power and is a biconcave lens, including one concave surface facing the object side and another concave surface facing the image side. The fifth lens has positive refractive power and includes a convex surface facing the object side. The sixth lens has refractive power and includes a concave surface facing the object side. The first, second, third, fourth, fifth, and sixth lenses are arranged sequentially along the optical axis from the object side to the image side.

[0005] The third lens has positive refractive power, and the sixth lens has positive refractive power.

[0006] The first lens includes a convex surface facing the object side and a concave surface facing the image side.

[0007] The second lens includes a concave surface facing the object side and a convex surface facing the image side.

[0008] The third lens is a biconvex lens, comprising one convex surface facing the object side and another convex surface facing the image side.

[0009] The fifth lens is a biconvex lens, and may further include another convex surface facing the image side.

[0010] The sixth lens is a meniscus lens and may further include a convex surface facing the image side.

[0011] The wide-angle lens of the present invention may further include an aperture disposed between the second lens and the third lens.

[0012] The wide-angle lens satisfies at least one of the following conditions: 0.6 < |R 11 / R 41 | < 2.4; 4 < R 21 / (R 12 +R 22 ) < 13.5; 9.9 < R 42 / CT4 < 103; 1.3 < R 51 / (f2-CT5) < 3.5; 4 < f2 / (CT2-CT6) < 8.2; wherein, R 11 is the curvature radius of the object-side surface of the first lens, R 12 is the curvature radius of the image-side surface of the first lens, R 21 is the curvature radius of the object-side surface of the second lens, R 22 is the curvature radius of the image-side surface of the second lens, R 41 is the curvature radius of the object-side surface of the fourth lens, R 42 is the curvature radius of the image-side surface of the fourth lens, R 51 is the curvature radius of the object-side surface of the fifth lens, CT2 is the distance on the optical axis from the object-side surface to the image-side surface of the second lens, CT4 is the distance on the optical axis from the object-side surface to the image-side surface of the fourth lens, CT5 is the distance on the optical axis from the object-side surface to the image-side surface of the fifth lens, CT6 is the distance on the optical axis from the object-side surface to the image-side surface of the sixth lens, and f2 is the effective focal length of the second lens.

[0013] The wide-angle lens satisfies the following conditions: -13 < (R 42 +R 41 ) / R 32 < 0.3; 5mm < |R 61 / Nd1| < 15mm; 11mm < |R 41 -f2| < 25mm; -3.2 < f1 / (R 41 +f5) < 2.3; 3.3mm < R 42 / (Vd3 / Vd4) < 30mm; wherein, R 32 is the curvature radius of the image-side surface of the third lens, R 41 is the curvature radius of the object-side surface of the fourth lens, R 42 is the curvature radius of the image-side surface of the fourth lens, R 61 is the curvature radius of the object-side surface of the sixth lens, Nd1 is the refractive index of the first lens, f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, f5 is the effective focal length of the fifth lens, Vd3 is the Abbe number of the third lens, and Vd4 is the Abbe number of the fourth lens.

[0014] Implementing the wide-angle lens of the present invention has the following beneficial effects: it has a large field of view and high resolution, and still has good optical performance. Attached Figure Description

[0015] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings.

[0016] Figure 1 This is a schematic diagram of the lens configuration and optical path according to a first embodiment of the wide-angle lens of the present invention.

[0017] Figure 2A , 2B 2C and 2D are respectively the longitudinal aberration diagram, field curvature diagram, distortion diagram, and relative illumination diagram of the first embodiment of the wide-angle lens according to the present invention.

[0018] Figure 3 This is a schematic diagram of the lens configuration and optical path according to a second embodiment of the wide-angle lens of the present invention.

[0019] Figure 4A , 4B 4C and 4D are respectively the longitudinal aberration diagram, field curvature diagram, distortion diagram, and relative illumination diagram of the second embodiment of the wide-angle lens according to the present invention.

[0020] Figure 5 This is a schematic diagram of the lens configuration and optical path according to a third embodiment of the wide-angle lens of the present invention.

[0021] Figure 6A , 6B 6C and 6D are respectively the longitudinal aberration diagram, field curvature diagram, distortion diagram, and relative illumination diagram of the third embodiment of the wide-angle lens according to the present invention. Detailed Implementation

[0022] This invention provides a wide-angle lens, comprising: a first lens having negative refractive power, the first lens being a meniscus lens, and including a convex surface facing the object side and a concave surface facing the image side; a second lens having positive refractive power, the second lens being a meniscus lens, and including a concave surface facing the object side and a convex surface facing the image side; a third lens having refractive power; a fourth lens having negative refractive power, the fourth lens being a biconcave lens, and including a concave surface facing the object side and another concave surface facing the image side; a fifth lens having positive refractive power, the fifth lens including a convex surface facing the object side; and a sixth lens having refractive power, the sixth lens including a concave surface facing the object side; wherein the first lens, second lens, third lens, fourth lens, fifth lens, and sixth lens are arranged sequentially along the optical axis from the object side to the image side.

[0023] Please refer to Tables 1, 2, 4, 5, 7, and 8 below. Tables 1, 4, and 7 are parameter tables for each lens according to the first to third embodiments of the wide-angle lens of the present invention. Tables 2, 5, and 8 are parameter tables for the aspherical surface of the aspherical lens in Tables 1, 4, and 7. In the following embodiments, the aspherical surface concavity z of the aspherical lens is obtained by the following formula: z = ch 2 / {1+[1-(k+1)c 2 h 2 ] 1 / 2}+Ah 4 +Bh 6 +Ch 8 +Dh 10 Where: c is the curvature, h is the perpendicular distance from any point on the lens surface to the optical axis, k is the conic constant, A to D are the aspherical coefficients, and E represents the scientific notation, such as E-03 indicating 10. -3 .

[0024] Figure 1 , 3Figures 5 and 6 are schematic diagrams of lens configuration and optical path of the first, second, and third embodiments of the wide-angle lens of the present invention, respectively. The first lenses L11, L21, and L31 are meniscus lenses with negative refractive power, made of plastic. Their object-side surfaces S11, S21, and S31 are convex, and their image-side surfaces S12, S22, and S32 are concave. Both object-side surfaces S11, S21, and S31 and image-side surfaces S12, S22, and S32 are aspherical surfaces. The second lenses L12, L22, and L32 are meniscus lenses with positive refractive power, made of plastic. Their object-side surfaces S13, S23, and S33 are concave, and their image-side surfaces S14, S24, and S34 are convex. Both object-side surfaces S13, S23, and S33 and image-side surfaces S14, S24, and S34 are aspherical surfaces. The third lenses, L13, L23, and L33, are biconvex lenses with positive refractive power, made of plastic. Their object-side surfaces S16, S26, and S36 are convex, and their image-side surfaces S17, S27, and S37 are convex. Both the object-side surfaces S16, S26, and S36 and the image-side surfaces S17, S27, and S37 are aspherical surfaces. The fourth lenses, L14, L24, and L34, are biconcave lenses with negative refractive power, made of plastic. Their object-side surfaces S18, S28, and S38 are concave, and their image-side surfaces S19, S29, and S39 are concave. Both the object-side surfaces S18, S28, and S38 and the image-side surfaces S19, S29, and S39 are aspherical surfaces. The fifth lenses, L15, L25, and L35, are biconvex lenses made of plastic. Their object-side surfaces S110, S210, and S310 are convex, and their image-side surfaces S111, S211, and S311 are also convex. Both the object-side surfaces S110, S210, and S310 and the image-side surfaces S111, S211, and S311 are aspherical surfaces. The sixth lenses, L16, L26, and L36, are meniscus lenses with positive refractive power made of plastic. Their object-side surfaces S112, S212, and S312 are concave, and their image-side surfaces S113, S213, and S313 are convex. Both the object-side surfaces S112, S212, and S312 and the image-side surfaces S113, S213, and S313 are aspherical surfaces.

[0025] In the wide-angle lens of this invention, each of the first to sixth lenses can have an air gap between any two adjacent lenses on the optical axis. That is, the first, second, third, fourth, fifth, and sixth lenses can be six single, non-cemented lenses. Since the manufacturing process of cemented lenses is more complex than that of non-cemented lenses, especially since the cementing surfaces of the two lenses need to have highly precise curvature to achieve a high degree of fit when the two lenses are cemented, and misalignment during the cementing process can also cause poor fit, affecting the overall optical imaging quality. Therefore, in the wide-angle lens of this invention, any two adjacent lenses can have an air gap on the optical axis, ensuring ease of assembly and increasing assembly yield.

[0026] In addition, wide-angle lenses 1, 2, and 3 must meet at least one of the following conditions:

[0027] 0.6<|R 11 / R 41 |<2.4; (1)

[0028] 4 <R 21 / (R 12 +R 22 (2) < 13.5;

[0029] 9.9 <R 42 / CT4<103; (3)

[0030] 1.3 <R 51 / (f2-CT5)<3.5; (4)

[0031] 4 <f2 / (CT2-CT6)<8.2; (5)

[0032] 5mm<|R 61 / Nd1∣<15mm; (6)

[0033] 11mm<|R 41 -f2 | < 25 mm; (7)

[0034] -3.2 <f1 / (R 41 +f5)<2.3; (8)

[0035] -13<(R 42 +R 41 ) / R 32 <0.3; (9)

[0036] 3.3mm <R 42 / (Vd3 / Vd4)<30mm; (10)

[0037] Among them, R 11 In the first to third embodiments, R represents the radius of curvature R of the object-side surfaces S11, S21, and S31 of the first lenses L11, L21, and L31. 12 In the first to third embodiments, R represents the radii of curvature of the image-side surfaces S12, S22, and S32 of the first lenses L11, L21, and L31. 21 In the first to third embodiments, R represents the radii of curvature of the object-side surfaces S13, S23, and S33 of the second lenses L12, L22, and L32. 22 In the first to third embodiments, R represents the radii of curvature of the image-side surfaces S14, S24, and S34 of the second lenses L12, L22, and L32. 32In the first to third embodiments, R represents the radii of curvature of the image-side surfaces S17, S27, and S37 of the third lenses L13, L23, and L33. 41 In the first to third embodiments, R represents the radii of curvature of the object-side surfaces S18, S28, and S38 of the fourth lenses L14, L24, and L34. 42 In the first to third embodiments, R represents the radii of curvature of the image-side surfaces S19, S29, and S39 of the fourth lenses L14, L24, and L34. 51 In the first to third embodiments, R represents the radii of curvature of the object-side surfaces S110, S210, and S310 of the fifth lenses L15, L25, and L35. 61 In the first to third embodiments, CT2 represents the radius of curvature of the object-side surfaces S112, S212, and S312 of the sixth lenses L16, L26, and L36; CT2 represents the distance between the object-side surfaces S13, S23, and S33 of the second lenses L12, L22, and L32 and the image-side surfaces S14, S24, and S34 on the optical axes OA1, OA2, and OA3 in the first to third embodiments; CT4 represents the distance between the object-side surfaces S18, S28, and S38 of the fourth lenses L14, L24, and L34 and the image-side surfaces S19, S29, and S39 on the optical axes OA1, OA2, and OA3 in the first to third embodiments; CT5 represents the distance between the object-side surfaces S110, S210, and S310 of the fifth lenses L15, L25, and L35 and the image-side surfaces S111, S211, and S311 on the optical axes OA1, OA2, and OA3 in the first to third embodiments; and CT6 represents... In the first to third embodiments, the distance between the object-side surfaces S112, S212, S312 and the image-side surfaces S113, S213, S313 of the sixth lenses L16, L26, L36 on the optical axes OA1, OA2, OA3 is: f1 is the effective focal length of the first lenses L11, L21, L31 in the first to third embodiments; f2 is the effective focal length of the second lenses L12, L22, L32 in the first to third embodiments; f5 is the effective focal length of the fifth lenses L15, L25, L35 in the first to third embodiments; Nd1 is the refractive index of the first lenses L11, L21, L31 in the first to third embodiments; Vd3 is the Abbe coefficient of the third lenses L13, L23, L33 in the first to third embodiments; and Vd4 is the Abbe coefficient of the fourth lenses L14, L24, L34 in the first to third embodiments. This allows wide-angle lenses 1, 2, and 3 to effectively improve the field of view, effectively improve resolution, and effectively correct aberrations.

[0038] When condition (1) is met: 0.6 < |R 11 / R 41|<2.4, sufficient refractive power can be provided for the wide-angle lens to control the field of view and facilitate aberration correction. When condition (2) is satisfied: 4<R 21 / (R 12 +R 22 )<13.5, sufficient refractive power can be provided for the wide-angle lens to control the field of view and facilitate aberration correction. When condition (3) is satisfied: 9.9<R 42 / CT4<103, the fourth lens can have appropriate thickness and focal length to correct off-axis aberrations. When condition (4) is satisfied: 1.3<R 51 / (f2-CT5)<3.5, the fifth lens can have appropriate thickness and focal length to correct off-axis aberrations. When condition (5) is satisfied: 4<f2 / (CT2-CT6)<8.2, the second lens and the fifth lens can have appropriate thickness and focal length to correct off-axis aberrations. When condition (6) is satisfied: 5mm<|R 61 / Nd1|<15mm, aberrations can be corrected and resolution can be improved. When condition (7) is satisfied: 11mm<|R 41 -f2|<25mm, aberrations can be corrected and resolution can be improved. When condition (8) is satisfied: -3.2<f1 / (R 41 +f5)<2.3, aberrations can be corrected and resolution can be improved. When condition (9) is satisfied: -13<(R 42 +R 41 ) / R 32 <0.3, aberrations can be corrected and resolution can be improved. When condition (10) is satisfied: 3.3mm<R 42 / (Vd3 / Vd4)<30mm, aberrations can be corrected and resolution can be improved.

[0039] The first embodiment of the wide-angle lens of the present invention will be described in detail below. Refer to Figure 1 , the wide-angle lens 1 sequentially comprises a first lens L11, a second lens L12, a stop ST1, a third lens L13, a fourth lens L14, a fifth lens L15, a sixth lens L16, an optical filter OF1 and a protective glass CG1 along an optical axis OA1 from the object side to the image side. During imaging, light from the object side is finally imaged on an imaging surface IMA1. According to the first to third paragraphs of [Detailed Description], wherein: both the object side surface S114 and the image side surface S115 of the optical filter OF1 are flat surfaces; both the object side surface S116 and the image side surface S117 of the protective glass CG1 are flat surfaces; by means of the design of the above lenses, the stop ST1 and satisfying at least one of conditions (1) to (10), the wide-angle lens 1 can effectively expand the field of view, effectively improve resolution, and effectively correct aberrations.

[0040] Table 1 is a Figure 1 relevant parameter table of each lens of the wide-angle lens 1 therein.

[0041] Table 1

[0042]

[0043]

[0044] Table 2 is a table of relevant parameters for the aspherical surface of the aspherical lens in Table 1.

[0045] Table 2

[0046] S11 -1.044 -1.26E-04 -1.03E-05 1.35E-07 0 S12 -0.916 1.02E-03 3.39E-05 -3.23E-06 0 S13 0.000 -2.34E-03 1.17E-04 -1.34E-06 0 S14 -1.633 2.72E-03 -1.50E-04 9.20E-06 0 S16 0.000 0.00E+00 0.00E+00 0.00E+00 0 S17 -1514.254 9.01E-03 -1.21E-03 1.51E-04 -1.14E-05 S18 2.869 3.52E-03 -6.61E-04 1.19E-04 -9.29E-06 S19 0.000 -8.58E-03 7.23E-04 -5.75E-05 -1.01E-06 S110 -3.434 -3.52E-03 4.55E-04 -3.19E-05 7.06E-07 S111 -0.499 2.11E-03 -2.11E-04 1.03E-05 -2.19E-07 S112 0.000 2.06E-03 6.01E-05 -4.42E-06 1.94E-07 S113 0.000 5.23E-04 -1.31E-04 9.99E-08 6.61E-08

[0047] Table 3 shows the relevant parameter values ​​of the wide-angle lens 1 in the first embodiment and the calculated values ​​of the corresponding conditions (1) to (10). As can be seen from Table 3, the wide-angle lens 1 in the first embodiment can meet the requirements of conditions (1) to (10).

[0048] Table 3

[0049] CT6 0.94mm <![CDATA[∣R 11 / R 41 ∣]]> 0.72 <![CDATA[R 21 / (R 12 +R 22 )]]> 4.99 <![CDATA[R 42 / CT4]]> 10.07 <![CDATA[R 51 / (f2-CT5)]]> 1.51 f2 / (CT2-CT6) 4.89 <![CDATA[∣R 61 / Nd1∣]]> 14.17mm <![CDATA[∣R 41 -f2∣]]> 23.90mm <![CDATA[f1 / (R 41 +f5)]]> 2.00 <![CDATA[(R 42 +R 41 ) / R 32 ]]> 0.19 <![CDATA[R 42 / (Vd3 / Vd4)]]> 3.66mm

[0050] Furthermore, the optical performance of the wide-angle lens 1 in the first embodiment also meets the requirements, by Figure 2A It can be seen that the longitudinal aberration of the wide-angle lens 1 in the first embodiment is between -0.08mm and 0.03mm. Figure 2B It can be seen that the field curvature of the wide-angle lens 1 in the first embodiment is between -0.12mm and 0.20mm. Figure 2C It can be seen that the distortion of the wide-angle lens 1 in the first embodiment is between -16% and 9%. Figure 2D It can be seen that the wide-angle lens 1 of the first embodiment provides a relative illuminance between 0.47 and 1.0 for light with a wavelength of 0.5550 μm in the Y field of view, which is between 0 mm and 6.4 mm. Clearly, the longitudinal aberration, field curvature, and distortion of the wide-angle lens 1 of the first embodiment can be effectively corrected, and the relative illuminance also meets the requirements, thus achieving better optical performance.

[0051] Please see Figure 3 , Figure 3This is a schematic diagram of the lens configuration and optical path according to a second embodiment of the wide-angle lens of the present invention. The wide-angle lens 2 includes, in sequence from the object side to the image side along the optical axis OA2, a first lens L21, a second lens L22, an aperture ST2, a third lens L23, a fourth lens L24, a fifth lens L25, a sixth lens L26, a filter OF2, and a protective glass CG2. During imaging, the light from the object side is finally imaged onto the imaging surface IMA2. According to the first to third paragraphs of the [Specific Embodiments], wherein: the object side S214 and the image side S215 of the filter OF2 are both planar; the object side S216 and the image side S217 of the protective glass CG2 are both planar; by utilizing the above-mentioned lens, aperture ST2, and the design that satisfies at least one of conditions (1) to (10), the wide-angle lens 2 can effectively improve the field of view, effectively improve the resolution, and effectively correct aberrations.

[0052] Table 4 is... Figure 3 Table of relevant parameters for each lens in medium wide-angle lens 2.

[0053] Table 4

[0054]

[0055]

[0056] Table 5 is a table of relevant parameters for the aspherical surface of the aspherical lens in Table 4.

[0057] Table 5

[0058] S21 -2.245 -2.77E-04 -2.03E-06 1.13E-07 0 S22 -0.911 1.15E-03 8.83E-05 -2.71E-06 0 S23 -1.923 -4.94E-03 1.17E-05 8.78E-06 0 S24 -1.740 4.05E-03 -4.75E-04 3.64E-05 0 S26 0.000 0.00E+00 0.00E+00 0.00E+00 0 S27 0.000 1.56E-02 -2.06E-03 2.95E-04 -2.36E-05 S28 3.382 6.19E-03 -1.06E-03 2.41E-04 -1.88E-05 S29 0.000 -1.24E-02 8.97E-04 -1.95E-05 -1.58E-05 S210 0.000 -3.77E-03 8.57E-04 -7.47E-05 2.27E-06 S211 2.491 3.42E-03 -4.07E-04 2.27E-05 -5.16E-07 S212 -0.094 3.16E-03 7.47E-05 -9.61E-06 4.27E-07 S213 -0.331 2.46E-03 -2.32E-04 2.74E-07 1.73E-07

[0059] Table 6 shows the relevant parameter values ​​of the wide-angle lens 2 in the second embodiment and the calculated values ​​of the corresponding conditions (1) to (10). As can be seen from Table 6, the wide-angle lens 2 in the second embodiment can meet the requirements of conditions (1) to (10).

[0060] Table 6

[0061] CT6 2.22mm <![CDATA[∣R 11 / R 41 ∣]]> 2.21 <![CDATA[R 21 / (R 12 +R 22 )]]> 12.88 <![CDATA[R 42 / CT4]]> 38.75 <![CDATA[R 51 / (f2-CT5)]]> 3.24 f2 / (CT2-CT6) 7.10 <![CDATA[∣R 61 / Nd1∣]]> 5.65mm <![CDATA[∣R 41 -f2∣]]> 12.52mm <![CDATA[f1 / (R 41 +f5)]]> -3.01 <![CDATA[(R 42 +R 41 ) / R 32 ]]> -4.44 <![CDATA[R 42 / (Vd3 / Vd4)]]> 11.42mm

[0062] Furthermore, the optical performance of the wide-angle lens 2 in the second embodiment also meets the requirements, by Figure 4A It can be seen that the longitudinal aberration of the wide-angle lens 2 in the second embodiment is between -0.20mm and 0.05mm. Figure 4B It can be seen that the field curvature of the wide-angle lens 2 in the second embodiment is between -0.35mm and 0.15mm. Figure 4C It can be seen that the distortion of the wide-angle lens 2 in the second embodiment is between -10% and 9%. Figure 4DIt can be seen that the wide-angle lens 2 of the second embodiment provides a relative illuminance between 0.38 and 1.0 for light with a wavelength of 0.5550μm in the Y field of view, which is between 0mm and 6.4mm. Clearly, the longitudinal aberration, field curvature, and distortion of the wide-angle lens 2 of the second embodiment can be effectively corrected, and the relative illuminance also meets the requirements, thus achieving better optical performance.

[0063] Please see Figure 5 , Figure 5 This is a schematic diagram of the lens configuration and optical path of a third embodiment of a wide-angle lens according to the present invention. The wide-angle lens 3 includes, in sequence from the object side to the image side along the optical axis OA3, a first lens L31, a second lens L32, an aperture ST3, a third lens L33, a fourth lens L34, a fifth lens L35, a sixth lens L36, a filter OF3, and a protective glass CG3. During imaging, the light from the object side is finally imaged onto the imaging surface IMA3. According to the first to third paragraphs of the [Specific Embodiments], wherein: the object side S314 and the image side S315 of the filter OF3 are both planar; the object side S316 and the image side S317 of the protective glass CG3 are both planar; by utilizing the above-mentioned lens, aperture ST3, and the design that satisfies at least one of conditions (1) to (10), the wide-angle lens 3 can effectively improve the field of view, effectively improve the resolution, and effectively correct aberrations.

[0064] Table 7 is... Figure 5 Table of relevant parameters for each lens in the medium wide-angle lens 3.

[0065] Table 7

[0066]

[0067] Table 8 is a table of relevant parameters for the aspherical surface of the aspherical lens in Table 7.

[0068] Table 8

[0069]

[0070]

[0071] Table 9 shows the relevant parameter values ​​of the wide-angle lens 3 in the third embodiment and the calculated values ​​of the corresponding conditions (1) to (10). As can be seen from Table 9, the wide-angle lens 3 in the third embodiment can meet the requirements of conditions (1) to (10).

[0072] Table 9

[0073] CT6 2.22mm <![CDATA[∣R 11 / R 41 ∣]]> 2.35 <![CDATA[R 21 / (R 12 +R 22 )]]> 13.33 <![CDATA[R 42 / CT4]]> 102.63 <![CDATA[R 51 / (f2-CT5)]]> 3.16 f2 / (CT2-CT6) 7.99 <![CDATA[∣R 61 / Nd1∣]]> 5.22mm <![CDATA[∣R 41 -f2∣]]> 12.13mm <![CDATA[f1 / (R 41 +f5)]]> -2.51 <![CDATA[(R 42 +R 41 ) / R 32 ]]> -12.83 <![CDATA[R 42 / (Vd3 / Vd4)]]> 29.84mm

[0074] Furthermore, the optical performance of the wide-angle lens 3 in the third embodiment also meets the requirements, by Figure 6AIt can be seen that the longitudinal aberration of the wide-angle lens 3 in the third embodiment is between -0.20mm and 0.05mm. Figure 6B It can be seen that the field curvature of the wide-angle lens 3 in the third embodiment is between -0.30mm and 0.15mm. Figure 6C It can be seen that the distortion of the wide-angle lens 3 in the third embodiment is between -12% and 8%. Figure 6D It can be seen that the wide-angle lens 3 of the third embodiment provides a relative illumination of 0.40 to 1.0 for light with a wavelength of 0.5550μm in the Y field of view, which is between 0mm and 6.4mm. Clearly, the longitudinal aberration, field curvature, and distortion of the wide-angle lens 3 of the third embodiment can be effectively corrected, and the relative illumination also meets the requirements, thus achieving better optical performance.

[0075] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A wide-angle lens, characterized in that, It has six lenses, including: The first lens has negative refractive power. The first lens is a meniscus lens, including a convex surface facing the object side and a concave surface facing the image side. The second lens has positive refractive power. The second lens is a meniscus lens, including a concave surface facing the object side and a convex surface facing the image side. The third lens has positive refractive power. The third lens is a biconvex lens, including one convex surface facing the object side and another convex surface facing the image side. The fourth lens has negative refractive power. The fourth lens is a biconcave lens, including one concave surface facing the object side and another concave surface facing the image side. The fifth lens has positive refractive power and is a biconvex lens, including one convex surface facing the object side and another convex surface facing the image side; and The sixth lens has positive refractive power. The sixth lens is a meniscus lens, including 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, the fifth lens, and the sixth lens are arranged sequentially along the optical axis from the object side to the image side; This wide-angle lens meets the following conditions: 11 mm < ∣R 41 -f2∣ < 25 mm; Where f2 is the effective focal length of the second lens, and R 41 Let be the radius of curvature of the object-side surface of the fourth lens.

2. The wide-angle lens as described in claim 1, characterized in that, It also includes an aperture positioned between the second lens and the third lens.

3. The wide-angle lens as described in any one of claims 1 to 2, characterized in that, The wide-angle lens must meet at least one of the following conditions: 0.6 < ∣R 11 / R 41 ∣ < 2.4; 4 < R 21 / (R 12 +R 22 ) < 13.5; 9.9 <R 42 / CT4 < 103; 1.3 < R 51 / (f2-CT5) < 3.5; 4 < f2 / (CT2-CT6) < 8.2; Among them, R 11 R is the radius of curvature of the object-side surface of the first lens. 12 R is the radius of curvature of the image-side surface of the first lens. 21 R is the radius of curvature of the object-side surface of the second lens. 22 R is the radius of curvature of the image-side surface of the second lens. 41 R is the radius of curvature of the object-side surface of the fourth lens. 42 R is the radius of curvature of the image-side surface of the fourth lens. 51 CT2 is the radius of curvature of the object side of the fifth lens, CT4 is the distance between the object side and the image side of the second lens on the optical axis, CT5 is the distance between the object side and the image side of the fourth lens on the optical axis, and CT6 is the distance between the object side and the image side of the fifth lens on the optical axis.

4. The wide-angle lens as described in any one of claims 1 to 2, characterized in that, This wide-angle lens meets the following conditions: -13 < (R 42 +R 41 ) / R 32 < 0.3; 5 mm < ∣R 61 / Nd1∣ < 15 mm; -3.2 < f1 / (R 41 +f5) < 2.3; 3.3 mm < R 42 / (Vd3 / Vd4) < 30 mm; Among them, R 32 R is the radius of curvature of the image-side surface of the third lens. 41 R is the radius of curvature of the object-side surface of the fourth lens. 42 R is the radius of curvature of the image-side surface of the fourth lens. 61 Let Nd1 be the radius of curvature of the object side of the sixth lens, f1 be the refractive index of the first lens, f5 be the effective focal length of the first lens, f5 be the effective focal length of the fifth lens, Vd3 be the Abbe coefficient of the third lens, and Vd4 be the Abbe coefficient of the fourth lens.

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