TWM575119U - Seven-piece wide-angle lens - Google Patents

Abstract

A seven-piece wide-angle lens comprising a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens and a seventh lens from the object side to the image side . The first lens has a negative refractive power, the object side is convex and the image side is concave. The second lens has a negative refractive power and its image side is concave. The third lens has a positive refractive power and a convex side of the image side. The fourth lens has a positive refractive power, and both the object side and the image side surface are convex. The fifth lens has a negative refractive power and its image side is concave. The sixth lens has a positive refractive power and a convex side of the object side. The seventh lens has a positive refractive power, and both the object side and the image side surface are convex. And the following relationship is satisfied: │f1+f2│/F<5, f1 is the focal length of the first lens, and f2 is the focal length of the second lens.

Description

Seven-chip wide-angle lens

This work is about an optical system, especially a seven-piece wide-angle lens with wide-angle characteristics.

A wide-angle lens is a lens with a short focal length and a large viewing angle. It is characterized by a long depth of field, a wide range of scenes, and a sense of space.

Among them, when the angle of view of the wide-angle lens is enlarged, the peripheral aberration is often caused. Therefore, how to provide a seven-chip wide-angle lens that can correct peripheral aberrations is considered by those skilled in the art.

The main purpose of this creation is to provide a seven-piece wide-angle lens that corrects peripheral aberrations.

In order to achieve the above and other objects, the present invention provides a seven-piece wide-angle lens, which includes a first lens, a second lens, a third lens, a fourth lens, an aperture, and a first lens from the object side to the image side. a fifth lens, a sixth lens and a seventh lens. The first lens has a negative refractive power, the object side is convex and its image side is concave. The second lens has a negative refractive power and its image side is concave. The third lens has a positive refractive power and its image side is convex. The fourth lens has a positive refractive power, and the object side surface and the image side surface thereof are both convex. The fifth lens has a negative refractive power and its image side is concave. The sixth lens has a positive refractive power and a convex side of the object side. The seventh lens has a positive refractive power, and the object side surface and the image side surface thereof are both convex. Wherein, the seven-piece wide-angle lens further satisfies the following relationship: │f1+f2│/F<5, the f1 is the focal length of the first lens, f2 is the focal length of the second lens, and F is the focal length of the system. By appropriately distributing the negative refractive powers of the first lens and the second lens, the incident angle of the peripheral light can be slowed down, and the peripheral aberration can be reduced when the optical system expands the viewing angle.

The present invention further provides a seven-piece wide-angle lens, which is a seven-piece wide-angle lens, which includes a first lens, a second lens, a third lens, a fourth lens, an aperture, and a first lens. a fifth lens, a sixth lens and a seventh lens. The first lens has a negative refractive power, and the radius of curvature of the object side surface is larger than the radius of curvature of the image side surface thereof, and the product of the curvature radius of the object side surface and the curvature radius of the image side surface thereof is a positive value. The second lens has a negative refractive power, and the radius of curvature of the image side is positive. The third lens has a positive refractive power, and the radius of curvature of the image side surface is a negative value. The fourth lens has a positive refractive power, and the radius of curvature of the object side surface is larger than the radius of curvature of the image side surface thereof, and the product of the curvature radius of the object side surface and the curvature radius of the image side surface thereof is a negative value. The fifth lens has a negative refractive power, and the radius of curvature of the image side is positive. The sixth lens has a positive refractive power, and the radius of curvature of the object side surface is a positive value. The seventh lens has a positive refractive power, and a radius of curvature of the object side surface is larger than a curvature radius of the image side surface thereof, and a product of a curvature radius of the object side surface and a curvature radius of the image side surface thereof is a negative value. Among them, the seven-chip wide-angle lens more satisfies the following relationship: │f1+f2│/F<5. By appropriately distributing the negative refractive powers of the first lens and the second lens, the incident angle of the peripheral light can be slowed down, and the peripheral aberration can be reduced when the optical system expands the viewing angle.

The present invention further provides a seven-piece wide-angle lens, which is a seven-piece wide-angle lens, which includes a first lens, a second lens, a third lens, a fourth lens, an aperture, and a first lens. a fifth lens, a sixth lens and a seventh lens. The first lens has a negative refractive power, the object side is convex and its image side is concave. The second lens has a negative refractive power and its image side is concave. The third lens has a positive refractive power and its image side is convex. The fourth lens has a positive refractive power, and the object side surface and the image side surface thereof are both convex. The fifth lens has a negative refractive power, and the object side surface is convex and its image side surface is concave. The sixth lens has a positive refractive power and a convex side of the object side. The seventh lens has a positive refractive power, and the object side surface and the image side surface thereof are both convex. The seven-piece wide-angle lens more satisfies the following relationship: │f1+f2│/F<5. By appropriately distributing the negative refractive powers of the first lens and the second lens, the incident angle of the peripheral light can be slowed down, and the peripheral aberration can be reduced when the optical system expands the viewing angle.

The present invention further provides a seven-piece wide-angle lens, which is a seven-piece wide-angle lens, which includes a first lens, a second lens, a third lens, a fourth lens, an aperture, and a first lens. a fifth lens, a sixth lens and a seventh lens. The first lens has a negative refractive power, the object side is convex and its image side is concave. The second lens has a negative refractive power and its image side is concave. The third lens has a positive refractive power and its image side is convex. The fourth lens has a positive refractive power, and the object side surface and the image side surface thereof are both convex. The fifth lens has a negative refractive power, and the object side surface and the image side surface thereof are both concave. The sixth lens has a positive refractive power and a convex side of the object side. The seventh lens has a positive refractive power, and the object side surface and the image side surface thereof are both convex. Among them, the seven-chip wide-angle lens more satisfies the following relationship: │f1+f2│/F<5. By appropriately distributing the negative refractive powers of the first lens and the second lens, the incident angle of the peripheral light can be slowed down, and the peripheral aberration can be reduced when the optical system expands the viewing angle.

The seven-piece wide-angle lens can satisfy the following relationship: f34/F > 0, the f34 is the combined focal length of the third and fourth lenses, and F is the focal length of the system. Thereby, the third and fourth lenses can provide positive refractive power, which helps to compensate for the aberration caused by the first and second lenses.

The seven-piece wide-angle lens can satisfy the following relationship: ∣(R5+R6)/(R5-R6)∣>0.9, the R5 is the radius of curvature of the side surface of the third lens, and R6 is the image side of the third lens. The radius of curvature. Thereby, the surface shape of the third and fourth lenses can be better controlled, which contributes to improvement in lens manufacturability.

In the seven-piece wide-angle lens, at least one of the object side surface and the image side surface of the second lens has an aspherical structure. Thus, the distortion of the optical system can be corrected by the aspherical structure of the second lens.

In the seven-piece wide-angle lens, at least one of the object side surface and the image side surface of the seventh lens has an aspherical structure. Thus, the aberration of the optical system can be reduced by the aspherical structure of the seventh lens.

In the seven-piece wide-angle lens, the fifth lens and the sixth lens form a glued lens, which can effectively reduce system aberration.

The seven-piece wide-angle lens can satisfy the following relationship: 5 < R1/F < 7.5; 0.5 < R2/F < 1.5; -1 < F/f1 < 0; -500 < R3/F< 90; 0 < R4/ F < 2; -1 < F/f2 < 0; -10 < R5/ F < 2000; -6 < R6/F < 80; 0.2 < F/f3 < 0.5; 1 < R7/F < 3.5; -8 R8/F < 0; 0 < F/f4 < 1; -7 < R9/F < 60; 0 < R10/F < 2; -1.5 < F/f5 < 0; 0 <R11/F < 2; < R12/F < 10; 0 < F/f6 < 1; 2 < R13/F < 4; -25 < R14/F < 0; 0 < F/f7 < 1. Wherein R1 is the radius of curvature of the side surface of the first lens, R2 is the radius of curvature of the image side of the first lens, f1 is the focal length of the first lens; R3 is the radius of curvature of the side of the object of the second lens, and R4 is the second The radius of curvature of the image side of the lens, f2 is the focal length of the second lens; R5 is the radius of curvature of the side of the third lens, R6 is the radius of curvature of the image side of the third lens, and f3 is the focal length of the third lens; R7 is The radius of curvature of the side of the fourth lens object, R8 is the radius of curvature of the side of the fourth lens image, f4 is the focal length of the fourth lens; R9 is the radius of curvature of the side of the fifth lens object, and R10 is the radius of curvature of the side of the fifth lens image, F5 is the focal length of the fifth lens; R11 is the radius of curvature of the side of the sixth lens, R12 is the radius of curvature of the side of the sixth lens image, f6 is the focal length of the sixth lens; R13 is the radius of curvature of the side of the seventh lens, R14 For the radius of curvature of the side of the seventh lens image, f7 is the focal length of the seventh lens. In the front lens group, the first and second lenses have a negative refractive power, and the third lens and the fourth lens have a positive refractive power, and the second lens has a negative refractive power, which can slow down the large refractive power required by the first lens and cause the shape to be too Bend, which improves the manufacturability of the lens. The second lens has an aspherical structure on at least one side to effectively correct the distortion aberration, and the third and fourth lenses provide a positive refractive power to thereby attenuate the aberration caused by the first and second lenses. The fifth and sixth lenses of the rear mirror group are a glued lens, and the seventh lens has at least one aspherical structure, which can effectively reduce system aberration and improve image quality.

Please refer to FIG. 1 , which is a first embodiment of the present invention. The seven-piece wide-angle lens (hereinafter referred to as a seven-piece lens) sequentially includes an object from the object side A to the image side B on the optical axis L. A lens 10, a second lens 20, a third lens 30, a fourth lens 40, an aperture ST, a fifth lens 50, a sixth lens 60 and a seventh lens 70 are disposed on the image side B. There are CCD, CMOS or other photosensitive elements (not shown), and a flat lens 80 such as a filter and/or a protective glass may be disposed between the photosensitive element and the seventh lens 70, and the number of the flat lenses 80 may be increased or decreased according to requirements. Or not set. Wherein, the first, second, third, and fourth lenses 10, 20, 30, and 40 that are closer to the object side A than the aperture ST are the front mirror group; in contrast, the aperture ST is closer to the fifth side of the image side B. The sixth and seventh lenses 50, 60, and 70 are rear mirror groups.

The first thing to declare is that in this paper, when the surface of a curved surface is closer to the image side than the surface itself, the radius of curvature of the surface is positive; otherwise, when the surface of a curved surface is closer to the surface itself On the object side, the radius of curvature of the surface is negative. Unless otherwise stated, the concave, convex, and radius of curvature of the "side of the object" and "image side" refer to the surface shape and radius of curvature of the surface at the optical axis L.

In the first embodiment of the present invention, the first lens 10 has a negative refractive power, the object side surface is convex and the image side surface thereof is concave, and the curvature radius of the object side surface and the image side surface thereof are positive values, and the curvature of the object side surface The radius is larger than the radius of curvature of the side of the image.

The second lens 20 has a negative refractive power, the object side surface is a convex surface and the image side surface thereof is a concave surface, and the curvature radius of the object side surface and the image side surface thereof are both positive values, and the curvature radius of the object side surface is larger than the curvature radius of the image side surface thereof.

The third lens 30 has a positive refractive power, the object side surface is a concave surface and the image side surface thereof is a convex surface, and the curvature radius of the object side surface and the image side surface thereof are both negative values, and the image side surface curvature radius thereof is larger than the curvature radius of the object side surface.

The fourth lens 40 has a positive refractive power, and the object side surface and the image side surface thereof are both convex surfaces, and the curvature radius of the object side surface is a positive value, and the curvature radius of the image side surface thereof is a negative value.

The fifth lens 50 has a negative refractive power, and the object side surface is a convex surface and the image side surface thereof is a concave surface, and the curvature radius of the object side surface and the image side surface thereof are both positive values, and the object side surface curvature radius is larger than the curvature radius of the image side surface.

The sixth lens 60 has a positive refractive power, the object side surface is convex and the image side surface thereof is concave, and the object side surface of the sixth lens 60 and the image side surface of the fifth lens 50 have the same radius of curvature and can be compared with the fifth lens 50. The sides are in close contact with one another to form a glued lens. The curvature radius of the object side surface and the image side surface of the sixth lens 60 is a positive value, and the curvature radius of the image side surface is larger than the curvature radius of the object side surface.

The seventh lens 70 has a positive refractive power, and the object side surface and the image side surface thereof are both convex surfaces, and the curvature radius of the object side surface is a positive value and the curvature radius of the image side surface thereof is a negative value. In the first embodiment, the first lens 10, the third lens 30, the fourth lens 40, the fifth lens 50, and the sixth lens 60 are glass lenses; and the second lens 70 and the seventh lens 70 are molded glass lenses.

The design parameters of the seven-piece lens of this embodiment are as shown in the following Table 1. It should be noted that the distance value corresponding to the side of the object represents the thickness of the lens, and the distance value corresponding to the side of the image represents the lens and the next lens or time. The spacing of an aperture on the optical axis:

<TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Table 1, first embodiment </td></tr><tr><td> The system focal length value F is 3.28 mm, the system length is 24 mm, and the maximum viewing angle is 156.3 ∘ </td></tr><tr><td> lens </td><td> surface </td><td> curvature Radius (mm) </td><td> distance </td><td> refractive index </td><td> chromatic dispersion coefficient </td><td> focal length </td></tr><tr>< Td> (mm) </td><td> (Nd) </td><td> (Vd) </td><td> (mm) </td></tr><tr><td> One lens </td><td> object side 1 </td><td> 18.14 </td><td> 0.69 </td><td> 1.73 </td><td> 54.68 </td><td > -7.7 </td></tr><tr><td> Image Side 2 </td><td> 4.24 </td><td> 2.77 </td></tr><tr><td> Second lens </td><td> object side 3 </td><td> 281.84 </td><td> 0.74 </td><td> 1.5 </td><td> 81.54 </td>< Td> -6.29 </td></tr><tr><td> image side 4 </td><td> 3.11 </td><td> 1.7 </td></tr><tr><td > Third lens</td><td> Side 5 </td><td> -23.69 </td><td> 1.63 </td><td> 1.78 </td><td> 26.21 </td ><td> 13.32 </td></tr><tr><td> Image side 6 </td><td> -7.56 </td><td> 0.04 </td></tr><tr> <td> fourth Slice </td><td> object side 7 </td><td> 8.98 </td><td> 4.55 </td><td> 1.74 </td><td> 28.28 </td><td> 5.99 </td></tr><tr><td> Image side 8 </td><td> -7.05 </td><td> 0.08 </td></tr><tr><td> Aperture </td><td> </td><td> ∞ </td><td> 0.03 </td><td> </td><td> </td><td> </td></ Tr><tr><td> fifth lens</td><td> object side 9 </td><td> 178.31 </td><td> 0.75 </td><td> 1.92 </td>< Td> 18.89 </td><td> -3.73 </td></tr><tr><td> Image side 10 </td><td> 3.45 </td><td> 0 </td>< /tr><tr><td> Sixth lens</td><td> Side 11 </td><td> 3.45 </td><td> 1.52 </td><td> 1.77 </td> <td> 49.59 </td><td> 4.89 </td></tr><tr><td> Image side 12 </td><td> 28.79 </td><td> 2.78 </td>< /tr><tr><td> Seventh lens</td><td> Side 13 </td><td> 8.33 </td><td> 2.32 </td><td> 1.74 </td> <td> 49.29 </td><td> 8.73 </td></tr><tr><td> Image Side 14 </td><td> -26.92 </td><td> 0.32 </td> </tr><tr><td> Flat Lens</td><td> Side 15 </td><td> ∞ </td><td> 1 </td><td> 1.52 </td> <td> 64.14 </td><td> </td></tr><tr><td> Image side Face 16 </td><td> ∞ </td><td> 3.08 </td><td> </td></tr></TBODY></TABLE>

According to Table 1, the following two values can be obtained:

Table II  <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Relationship </td><td> Value </td><td> Relationship </ Td><td> value</td></tr><tr><td> │f1+f2│/F </td><td> 4.27 </td><td> R10/F </td>< Td> 1.05 </td></tr><tr><td> F34/F </td><td> 17.30 </td><td> R11/F </td><td> 1.05 </td> </tr><tr><td> ∣(R5+R6)/(R5-R6)∣ </td><td> 1.94 </td><td> R12/F </td><td> 8.78 < /td></tr><tr><td> R1/F </td><td> 5.53 </td><td> R13/F </td><td> 2.54 </td></tr> <tr><td> R2/F </td><td> 1.29 </td><td> R14/F </td><td> -8.21 </td></tr><tr><td> R3/F </td><td> 85.93 </td><td> F/f1 </td><td> -0.43 </td></tr><tr><td> R4/F </td ><td> 0.95 </td><td> F/f2 </td><td> -0.52 </td></tr><tr><td> R5/F </td><td> -7.22 </td><td> F/f3 </td><td> 0.25 </td></tr><tr><td> R6/F </td><td> -2.30 </td><td > F/f4 </td><td> 0.55 </td></tr><tr><td> R7/F </td><td> 2.74 </td><td> F/f5 </td ><td> -0.88 </td></tr><tr><td> R8/F </td><td> -2.15 </td><td> F/f6 </td><td> 0.67 </td></tr><tr><td> R9/F </td><td> 54.36 </td><td> F/f7 </td><td> 0.3 8 </td></tr></TBODY></TABLE>

In the present embodiment, since the first lens 10 and the second lens 20 in the front lens group each have a negative refractive power, proper distribution through the negative refractive power can slow down the incident angle of the peripheral light, and can reduce the optical system when expanding the viewing angle. The generation of peripheral aberrations. By the addition of the negative refractive power of the second lens 20, the first lens 10 is required to form an overly curved surface structure to improve the manufacturability of the lens. On the other hand, since at least one of the object side surface and the image side surface of the second lens 20 has an aspherical structure, the distortion can be effectively corrected. The positive refractive power provided by the third lens 30 and the fourth lens 40 can compensate for the aberration caused by the first lens 10 and the second lens 20, and the third lens 30 can slow the change of the incident light angle, and can reduce the lens for The sensitivity of the light changes, and thereby improving the manufacturability of the lens of the overall optical system.

The fifth lens 50 and the sixth lens 60 in the rear lens group are a cemented lens, and at least one of the object side surface and the image side surface of the seventh lens 70 is an aspherical structure, which can effectively reduce the aberration of the optical system, and This improves the image quality.

The lateral light fan pattern of the different viewing angles is as shown in Figs. 1A to 1E, and it can be seen that the performance of the corrected chromatic aberration of this embodiment is very excellent. The field curvature performance is as shown in Fig. 1F, and the maximum field curvature is not more than ±0.08 mm; the distortion ratio is as shown in Fig. 1G, and the maximum distortion is less than ±80%. It is obvious that this embodiment has a good imaging effect.

Please refer to FIG. 2 , which is a second embodiment of the present invention. The lens configuration is similar to that of the first embodiment. The design parameters of the seven-piece lens of this embodiment are as shown in Table 3 below:

<TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Table 3, Second Embodiment </td></tr><tr><td> The system focal length value F is 3.21 mm, the system length is 24 mm, and the maximum viewing angle is 156.1 ∘ </td></tr><tr><td> lens </td><td> surface </td><td> curvature Radius (mm) </td><td> distance </td><td> refractive index </td><td> chromatic dispersion coefficient </td><td> focal length </td></tr><tr>< Td> (mm) </td><td> (Nd) </td><td> (Vd) </td><td> (mm) </td></tr><tr><td> One lens </td><td> object side 1 </td><td> 18.46 </td><td> 0.71 </td><td> 1.73 </td><td> 54.68 </td><td > -7.48 </td></tr><tr><td> Image side 2 </td><td> 4.16 </td><td> 2.66 </td></tr><tr><td> Second lens </td><td> object side 3 </td><td> 21.67 </td><td> 0.76 </td><td> 1.52 </td><td> 64.06 </td>< Td> -7.95 </td></tr><tr><td> image side 4 </td><td> 3.43 </td><td> 1.68 </td></tr><tr><td > Third lens</td><td> Side 5 </td><td> -9.91 </td><td> 2.41 </td><td> 1.78 </td><td> 26.22 </td ><td> 21.86 </td></tr><tr><td> Image side 6 </td><td> -7 </td><td> 0.04 </td></tr><tr> <td> Fourth mirror Slice </td><td> object side 7 </td><td> 5.96 </td><td> 3.9 </td><td> 1.74 </td><td> 28.28 </td><td> 6.69 </td></tr><tr><td> Image side 8 </td><td> -23.16 </td><td> 0.34 </td></tr><tr><td> Aperture </td><td> </td><td> ∞ </td><td> -0.01 </td><td> </td><td> </td><td> </td>< /tr><tr><td> Fifth Lens</td><td> Side 9 </td><td> 19.63 </td><td> 0.7 </td><td> 1.92 </td> <td> 18.89 </td><td> -3.63 </td></tr><tr><td> Image side 10 </td><td> 2.87 </td><td> 0 </td> </tr><tr><td> sixth lens</td><td> object side 11 </td><td> 2.87 </td><td> 1.53 </td><td> 1.77 </td ><td> 49.59 </td><td> 4.2 </td></tr><tr><td> Image Side 12 </td><td> 17.92 </td><td> 2.24 </td> </tr><tr><td> seventh lens</td><td> object side 13 </td><td> 12.43 </td><td> 2.65 </td><td> 1.74 </td ><td> 49.29 </td><td> 7.82 </td></tr><tr><td> Image Side 14 </td><td> -10.09 </td><td> 0.32 </td ></tr><tr><td> Flat Lens</td><td> Side 15 </td><td> ∞ </td><td> 1 </td><td> 1.52 </td ><td> 64.14 </td><td> </td></tr><tr><td> 16 </td><td> ∞ </td><td> 3.08 </td><td> </td></tr></TBODY></TABLE>

According to Table 3, you can get the following four values:

Table 4  <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Relationship </td><td> Value </td><td> Relationship </ Td><td> value</td></tr><tr><td> │f1+f2│/F </td><td> 4.81 </td><td> R10/F </td>< Td> 0.89 </td></tr><tr><td> F34/F </td><td> 17.67 </td><td> R11/F </td><td> 0.89 </td> </tr><tr><td> ∣(R5+R6)/(R5-R6)∣ </td><td> 5.81 </td><td> R12/F </td><td> 5.58 < /td></tr><tr><td> R1/F </td><td> 5.75 </td><td> R13/F </td><td> 3.87 </td></tr> <tr><td> R2/F </td><td> 1.30 </td><td> R14/F </td><td> -3.14 </td></tr><tr><td> R3/F </td><td> 6.75 </td><td> F/f1 </td><td> -0.43 </td></tr><tr><td> R4/F </td ><td> 1.07 </td><td> F/f2 </td><td> -0.40 </td></tr><tr><td> R5/F </td><td> -3.09 </td><td> F/f3 </td><td> 0.15 </td></tr><tr><td> R6/F </td><td> -2.18 </td><td > F/f4 </td><td> 0.48 </td></tr><tr><td> R7/F </td><td> 1.86 </td><td> F/f5 </td ><td> -0.88 </td></tr><tr><td> R8/F </td><td> -7.22 </td><td> F/f6 </td><td> 0.76 </td></tr><tr><td> R9/F </td><td> 6.12 </td><td> F/f7 </td><td> 0.41 </td></tr></TBODY></TABLE>

In the second embodiment, the lateral light fan patterns of different viewing angles are as shown in Figs. 2A to 2E, and it can be seen that the performance of the corrected chromatic aberration of the present embodiment is extremely excellent. The field curvature performance is as shown in Fig. 2F, the maximum field curvature is not more than ± 0.02 mm; the distortion ratio is as shown in Fig. 2G, and the maximum distortion is less than ± 70%. It is obvious that this embodiment has a good imaging effect.

Please refer to FIG. 3 , which is a third embodiment of the present invention. The lens configuration is similar to that of the first embodiment, except that the object side of the second lens 20 is concave; the object side of the third lens 30 The convex surface is convex; the object side surface of the fifth lens 50 is a concave surface; and the image side surface of the sixth lens 60 is a convex surface. The design parameters of the seven-piece lens of this embodiment are as shown in Table 5 below:

<TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Table 5, the third embodiment </td></tr><tr><td> The system focal length value F is 3.27 mm, the system length is 23.99 mm, and the maximum viewing angle is 156.1 ∘ </td></tr><tr><td> lens </td><td> surface </td><td> curvature Radius (mm) </td><td> distance </td><td> refractive index </td><td> chromatic dispersion coefficient </td><td> focal length </td></tr><tr>< Td> (mm) </td><td> (Nd) </td><td> (Vd) </td><td> (mm) </td></tr><tr><td> One lens </td><td> side 1 </td><td> 23.12 </td><td> 0.7 </td><td> 1.73 </td><td> 54.68 </td><td > -7.1 </td></tr><tr><td> Image Side 2 </td><td> 4.2 </td><td> 2.71 </td></tr><tr><td> Second lens </td><td> object side 3 </td><td> -1012.44 </td><td> 1.49 </td><td> 1.5 </td><td> 81.54 </td> <td> -6.56 </td></tr><tr><td> Image side 4 </td><td> 3.29 </td><td> 1.35 </td></tr><tr>< Td> third lens</td><td> object side 5 </td><td> 6248.96 </td><td> 1.85 </td><td> 1.78 </td><td> 26.22 </td ><td> 10.68 </td></tr><tr><td> Image side 6 </td><td> -8.52 </td><td> 0.04 </td></tr><tr> <td> Four lenses</td><td> object side 7 </td><td> 8.82 </td><td> 3.82 </td><td> 1.74 </td><td> 28.28 </td><td > 5.58 </td></tr><tr><td> Image side 8 </td><td> -6.51 </td><td> 0.06 </td></tr><tr><td> Aperture</td><td> </td><td> ∞ </td><td> 0.09 </td><td> </td><td> </td><td> </td>< /tr><tr><td> Fifth lens</td><td> Side 9 </td><td> -19.59 </td><td> 0.75 </td><td> 1.92 </td ><td> 18.89 </td><td> -3.45 </td></tr><tr><td> Image side 10 </td><td> 3.97 </td><td> 0 </td ></tr><tr><td> sixth lens</td><td> object side 11 </td><td> 3.97 </td><td> 1.56 </td><td> 1.77 </ Td><td> 49.59 </td><td> 4.88 </td></tr><tr><td> Image side 12 </td><td> -73.79 </td><td> 3 </ Td></tr><tr><td> seventh lens</td><td> object side 13 </td><td> 8.16 </td><td> 2.19 </td><td> 1.74 < /td><td> 49.29 </td><td> 9.89 </td></tr><tr><td> Image side 14 </td><td> -71.69 </td><td> 0.32 < /td></tr><tr><td> Flat Lens</td><td> Side 15 </td><td> ∞ </td><td> 1 </td><td> 1.52 < /td><td> 64.14 </td><td> </td></tr><tr><td> Side 16 </td><td> ∞ </td><td> 3.08 </td><td> </td></tr></TBODY></TABLE>

According to Table 5, the following six values can be obtained:

Table 6  <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Relationship </td><td> Value </td><td> Relationship </ Td><td> value</td></tr><tr><td> │f1+f2│/F </td><td> 4.18 </td><td> R10/F </td>< Td> 1.21 </td></tr><tr><td> F34/F </td><td> 17.35 </td><td> R11/F </td><td> 1.21 </td> </tr><tr><td> ∣(R5+R6)/(R5-R6)∣ </td><td> 1.00 </td><td> R12/F </td><td> -22.56 </td></tr><tr><td> R1/F </td><td> 7.07 </td><td> R13/F </td><td> 2.50 </td></tr ><tr><td> R2/F </td><td> 1.28 </td><td> R14/F </td><td> -21.92 </td></tr><tr><td > R3/F </td><td> -309.61 </td><td> F/f1 </td><td> -0.46 </td></tr><tr><td> R4/F < /td><td> 1.01 </td><td> F/f2 </td><td> -0.50 </td></tr><tr><td> R5/F </td><td> 1911.00 </td><td> F/f3 </td><td> 0.31 </td></tr><tr><td> R6/F </td><td> -2.60 </td>< Td> F/f4 </td><td> 0.59 </td></tr><tr><td> R7/F </td><td> 2.70 </td><td> F/f5 </ Td><td> -0.95 </td></tr><tr><td> R8/F </td><td> -1.99 </td><td> F/f6 </td><td> 0.67 </td></tr><tr><td> R9/F </td><td> -5.99 </td><td> F/f7 </td>< Td> 0.33 </td></tr></TBODY></TABLE>

In the third embodiment, the lateral light fan patterns of different viewing angles are as shown in Figs. 3A to 3E, and it can be seen that the performance of the corrected chromatic aberration of this embodiment is very excellent. The field curvature performance is as shown in Fig. 3F, the maximum field curvature is not more than ±0.06 mm; the distortion ratio is as shown in Fig. 3G, and the maximum distortion is less than ±70%. It is obvious that this embodiment has a good imaging effect.

10‧‧‧ first lens

20‧‧‧second lens

30‧‧‧ third lens

40‧‧‧Fourth lens

50‧‧‧ fifth lens

60‧‧‧ sixth lens

70‧‧‧ seventh lens

80‧‧‧ flat lenses

A‧‧‧ object side

B‧‧‧ image side

ST‧‧‧ aperture

L‧‧‧ optical axis

Figure 1 is a schematic view of the first embodiment of the creation.

1A to 1E are transverse light fan diagrams of the first embodiment at different viewing angles, showing a maximum scale of ±50 μm.

Fig. 1F is a field curvature diagram of the first embodiment of the creation.

Fig. 1G is a distortion diagram of the first embodiment of the creation.

Fig. 2 is a schematic view showing a second embodiment of the creation.

2A to 2E are transverse light fan diagrams of the second embodiment of the present invention at different viewing angles, and the maximum scale shown is ±50 μm.

Fig. 2F is a field curvature diagram of the second embodiment of the creation.

Fig. 2G is a distortion diagram of the second embodiment of the creation.

Figure 3 is a schematic view of a third embodiment of the creation.

3A to 3E are transverse light fan diagrams of the third embodiment of the present invention at different viewing angles, and the maximum scale shown is ±50 μm.

Fig. 3F is a field curvature diagram of the third embodiment of the creation.

Fig. 3G is a distortion diagram of the third embodiment of the creation.

Claims (16)

A seven-piece wide-angle lens comprising, in order from the object side to the image side, a first lens having a negative refractive power, a convex side of the object surface and a concave side of the image side surface; a second lens having a negative refractive power, the image side being a third lens having a positive refractive power and a convex side on the image side; a fourth lens having a positive refractive power, a side surface of the object and an image side thereof being convex; an aperture; a fifth lens having a negative refractive power; The image has a concave surface; a sixth lens having a positive refractive power and a convex side; and a seventh lens having a positive refractive power, the side surface of the object and the image side thereof being convex; wherein the seven-piece wide-angle lens is more satisfying The following relationship: │f1+f2│/F<5, where f1 is the focal length of the first lens, f2 is the focal length of the second lens, and F is the focal length of the system. A seven-piece wide-angle lens comprising, in order from the object side to the image side, a first lens having a negative refractive power, a radius of curvature of a side of the object being larger than a radius of curvature of the side of the image side, and a radius of curvature of the side of the object and a side thereof The product of the radius of curvature is positive; a second lens has a negative refractive power, and the radius of curvature of the image side is positive; a third lens has positive refractive power, and the radius of curvature of the image side is negative; , having a positive refractive power, the radius of curvature of the side of the object is larger than the radius of curvature of the side of the image, and the product of the radius of curvature of the side of the object and the radius of curvature of the side of the object is a negative value; an aperture; a fifth lens having a negative refractive power, The radius of curvature of the image side is positive; a sixth lens having a positive refractive power, the radius of curvature of the side of the object is a positive value; and a seventh lens having a positive refractive power, the radius of curvature of the side of the object being larger than the side of the image The radius of curvature, and the product of the radius of curvature of the side of the object and the radius of curvature of the side of the object is a negative value; wherein the seven-piece wide-angle lens more satisfies the following Department formula: │f1 + f2│ / F <5, wherein the focal length f1 of the first lens that, f2 the focal length of the second lens for, F is the focal length. A seven-piece wide-angle lens comprising, in order from the object side to the image side, a first lens having a negative refractive power, a convex side of the object surface and a concave side of the image side surface; a second lens having a negative refractive power, the image side being a third lens having a positive refractive power and a convex side on the image side; a fourth lens having a positive refractive power, a side surface of the object and an image side thereof being convex; an aperture; a fifth lens having a negative refractive power; a side surface of the object is convex and its image side is concave; a sixth lens having a positive refractive power and a convex side of the object side; and a seventh lens having a positive refractive power, the object side surface and the image side surface thereof being convex; The seven-piece wide-angle lens more satisfies the following relationship: │f1+f2│/F<5, where f1 is the focal length of the first lens, f2 is the focal length of the second lens, and F is the focal length of the system. A seven-piece wide-angle lens comprising, in order from the object side to the image side, a first lens having a negative refractive power, a convex side of the object surface and a concave side of the image side surface; a second lens having a negative refractive power, the image side being a third lens having a positive refractive power and a convex side on the image side; a fourth lens having a positive refractive power, a side surface of the object and an image side thereof being convex; an aperture; a fifth lens having a negative refractive power; a side surface and an image side surface thereof are concave surfaces; a sixth lens having a positive refractive power and a convex side surface; and a seventh lens having a positive refractive power, the object side surface and the image side surface thereof being convex; The wide-angle lens of the chip more satisfies the following relationship: │f1+f2│/F<5, where f1 is the focal length of the first lens, f2 is the focal length of the second lens, and F is the focal length of the system. The seven-piece wide-angle lens of claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: f34/F > 0; wherein f34 is a composite focal length of the third and fourth lenses. The seven-piece wide-angle lens according to claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: ∣(R5+R6)/(R5-R6)∣ > 0.9; wherein R5 is The radius of curvature of the side surface of the third lens, and R6 is the radius of curvature of the image side of the third lens. The seven-piece wide-angle lens of claim 1, 2, 3 or 4, wherein at least one of an object side surface or an image side surface of the second lens has an aspherical structure. The seven-piece wide-angle lens of claim 1, 2, 3 or 4, wherein at least one of an object side surface or an image side surface of the seventh lens has an aspherical structure. The seven-piece wide-angle lens of claim 1, 2, 3 or 4, wherein the fifth lens and the sixth lens form a glued lens. A seven-piece wide-angle lens as claimed in claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: 5 < R1/F < 7.5; 0.5 < R2/F < 1.5; -1 < F /f1 < 0; wherein R1 is the radius of curvature of the side surface of the first lens, R2 is the radius of curvature of the image side of the first lens, and f1 is the focal length of the first lens. A seven-piece wide-angle lens as claimed in claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: -500 < R3/F< 90; 0 < R4/F < 2; -1 < F/f2 < 0; wherein R3 is the radius of curvature of the side surface of the second lens, R4 is the radius of curvature of the image side of the second lens, and f2 is the focal length of the second lens. A seven-piece wide-angle lens as claimed in claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: -10 < R5/ F < 2000; -6 < R6/F < 80; 0.2 < F/f3 < 0.5; wherein R5 is the radius of curvature of the side surface of the third lens, R6 is the radius of curvature of the image side of the third lens, and f3 is the focal length of the third lens. A seven-piece wide-angle lens as claimed in claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: 1 < R7/F < 3.5; -8 < R8/F < 0; 0 < F /f4 < 1; wherein R7 is the radius of curvature of the side of the fourth lens, R8 is the radius of curvature of the side of the fourth lens image, and f4 is the focal length of the fourth lens. A seven-piece wide-angle lens as claimed in claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: -7 < R9/F < 60; 0 < R10/F < 2; -1.5 < F/f5 < 0; wherein R9 is the radius of curvature of the side surface of the fifth lens, R10 is the radius of curvature of the side of the fifth lens image, and f5 is the focal length of the fifth lens. A seven-piece wide-angle lens as claimed in claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: 0 <R11/F < 2; -25 < R12/F < 10; 0 < F /f6 < 1; wherein R11 is the radius of curvature of the side surface of the sixth lens, R12 is the radius of curvature of the side of the sixth lens image, and f6 is the focal length of the sixth lens. A seven-piece wide-angle lens as claimed in claim 1, 2, 3 or 4, wherein the seven-piece wide-angle lens further satisfies the following relationship: 2 < R13/F < 4; -25 < R14/F < 0; 0 < F /f7 < 1; wherein R13 is the radius of curvature of the side surface of the seventh lens, R14 is the radius of curvature of the side of the seventh lens image, and f7 is the focal length of the seventh lens.