A high-pixel and low-distortion optical lens

Abstract

The present invention belongs to the field of optical imaging, and in particular, relates to a high-pixel, low-distortion optical lens, comprising an optical module, wherein the optical module is sequentially provided with a front group S1 with negative focal length, a middle group S2 with positive focal length, an aperture, and a focusing group S3 with positive focal length from the object side to the image side; the focal length of the optical module is f, the focal length of the front group is fS1, the focal length of the middle group is fS2, and the focal length of the focusing group is fS3, which satisfies the relationship: 1.20<|fS1 / f|<1.60, 1.20<|fS2 / f|<1.60, 1.20<|fS3 / f|<1.60. The above structure realizes an optical module with a focal length of 16mm, an image side F number of 2.8, a maximum imaging surface with a maximum resolution of up to 200lp / mm, which can match a 2.5μm pixel chip, and a maximum optical distortion of the full field of view of less than 1.0%.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical imaging, and in particular relates to a high-pixel and low-distortion optical lens. Background Art

[0002] With the rise of modern industry, optical lenses are increasingly used, especially in the field of inspection applications, such as: size measurement, pin positioning, PCB board defect detection, floor tile surface texture and color detection, etc. As application needs continue to increase, the requirements for optical lenses are also getting higher and higher, especially in terms of field of view, optical distortion, resolution, etc. At the same time, camera chip pixels tend to be larger, and 20 million pixel 1.1″ chips are one of the current mainstream chips.

[0003] However, there are few optical lenses designed for 1.1″ chips in China, and there are deficiencies in distortion and lens size, especially in imaging at close distances. Therefore, the research and development of high-pixel, low-distortion optical lenses is more urgent. Summary of the invention

[0004] The purpose of the present invention is to provide a high-pixel and low-distortion optical lens for a 1.1″ camera chip to meet application requirements in view of the deficiencies of the prior art.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A high-pixel, low-distortion optical lens, comprising an optical module, wherein the optical module is provided with a front group S1 with negative optical power, a middle group S2 with positive optical power, an aperture and a focusing group S3 with positive optical power in sequence from the object side to the image side;

[0007] The front group S1 includes a first lens G1 with positive focal power and a meniscus structure, a second lens G2 with negative focal power and a meniscus structure, and a third lens G3 with negative focal power and a meniscus structure;

[0008] The middle lens group S2 includes a fourth lens G4 with negative focal power and a biconcave structure, a fifth lens G5 with positive focal power and a biconvex structure, a sixth lens G6 with negative focal power and a meniscus structure, and a seventh lens G7 with positive focal power and a biconvex structure; wherein the fourth lens G4 and the fifth lens G5 are cemented into a first cemented lens group U1 with negative focal power, and the sixth lens G6 and the seventh lens G7 are cemented into a second cemented lens group U2 with positive focal power;

[0009] The focusing group includes an eighth lens G8 with positive focal power and a meniscus structure, a ninth lens G9 with negative focal power and a meniscus structure, a tenth lens G10 with negative focal power and a biconcave structure, an eleventh lens G11 with positive focal power and a biconvex structure, and a twelfth lens G12 with positive focal power and a biconvex structure; wherein the eighth lens G8 and the ninth lens G9 are cemented into a third cemented lens group U3 with negative focal power; and the tenth lens G10 and the eleventh lens G11 are cemented into a fourth cemented lens group U4 with positive focal power;

[0010] The focal length of the optical module is f, the focal length of the front group is fS1, the focal length of the middle group is fS2, and the focal length of the focusing group is fS3, which satisfies the relationship: 1.20<|fS1 / f|<1.60, 1.20<|fS2 / f|<1.60, 1.20<|fS3 / f|<1.60.

[0011] As an improvement of the high-pixel and low-distortion optical lens of the present invention, the optical back focus BFL of the optical module and the focal length f of the optical module satisfy the relationship: |BFL / f|<1.50.

[0012] As an improvement of the high-pixel and low-distortion optical lens of the present invention, the half-image height y' of the optical module and the focal length f of the optical module satisfy the relationship: |y' / f|<0.7.

[0013] As an improvement of the high-pixel, low-distortion optical lens described in the present invention, the focal length of the first lens G1 is fG1, and the ratio of its focal length fG1 to the focal length f of the optical module satisfies the relationship: 2.80<|fG1 / f|<3.20; the focal length of the second lens G2 is fG2, and the ratio of its focal length fG2 to the focal length f of the optical module satisfies the relationship: 1.20<|fG2 / f|<1.80; the focal length of the third lens G3 is fG3, and the ratio of its focal length fG3 to the focal length f of the optical module satisfies the relationship: 1.80<|fG3 / f|<2.20.

[0014] As an improvement of the high-pixel, low-distortion optical lens of the present invention, the focal length of the first cemented lens group is fU1, and the ratio of its focal length fU1 to the focal length f of the optical module satisfies the relationship: 6.50<|fU1 / f|<7.00.

[0015] As an improvement of the high-pixel, low-distortion optical lens described in the present invention, the focal length of the second cemented lens group is fU2, and the ratio of its focal length fU2 to the focal length f of the optical module satisfies the relationship: 1.00<|fU2 / f|<1.50.

[0016] As an improvement of the high-pixel and low-distortion optical lens described in the present invention, the focal length of the third cemented lens group is fU3, and the ratio of its focal length fU3 to the focal length f of the optical module satisfies the relationship: 5.60<|fU3 / f|<6.40.

[0017] As an improvement of the high-pixel, low-distortion optical lens of the present invention, the focal length of the fourth cemented lens group is fU4, and the ratio of its focal length fU4 to the focal length f of the optical module satisfies the relationship: 52.00<|fU4 / f|<56.00.

[0018] As an improvement of the high-pixel and low-distortion optical lens of the present invention, the focal length of the twelfth lens G12 is fG12, and the ratio of the focal length fG12 to the focal length f of the optical module satisfies the relationship: 1.20<|fG12 / f|<1.60.

[0019] As an improvement of the high-pixel and low-distortion optical lens described in the present invention, each of the lenses is a spherical mirror, the diaphragm is an aperture diaphragm, and the aperture of the diaphragm is adjustable within the range of F2.8 to F16.

[0020] Compared with the prior art, the beneficial effects of the present invention include but are not limited to: the present invention provides a high-pixel and low-distortion optical lens, comprising an optical module, wherein the optical module is sequentially provided with a front group S1 with negative optical power, a middle group S2 with positive optical power, and a focusing group S3 with a stop and positive optical power from the object side to the image side; the front group S1 comprises a first lens G1 with positive optical power and a meniscus structure, a second lens G2 with negative optical power and a meniscus structure, and a third lens G3 with negative optical power and a meniscus structure; the middle group S2 comprises a fourth lens G4 with negative optical power and a biconcave structure, a fifth lens G5 with positive optical power and a biconvex structure, a sixth lens G6 with negative optical power and a meniscus structure, and a seventh lens G7 with positive optical power and a biconvex structure; wherein the fourth lens G4 and the fifth lens G5 are glued to form a first glued lens group U1 with negative optical power, and the sixth lens G6 and the seventh lens G7 are glued to form a positive optical power. a second cemented lens group U2; the focusing group comprises an eighth lens G8 with positive focal power and a meniscus structure, a ninth lens G9 with negative focal power and a meniscus structure, a tenth lens G10 with negative focal power and a biconcave structure, an eleventh lens G11 with positive focal power and a biconvex structure, and a twelfth lens G12 with positive focal power and a biconvex structure; wherein the eighth lens G8 and the ninth lens G9 are cemented into a third cemented lens group U3 with negative focal power; the tenth lens G10 and the eleventh lens G11 are cemented into a fourth cemented lens group U4 with positive focal power; the focal length of the optical module is f, the focal length of the front group is fS1, the focal length of the middle group is fS2, and the focal length of the focusing group is fS3, which satisfy the relationship: 1.20<|fS1 / f|<1.60, 1.20<|fS2 / f|<1.60, 1.20<|fS3 / f|<1.60. The present invention realizes an optical module with a focal length of 16 mm, an image side F number of 2.8, and a maximum imaging surface of The highest resolution can reach 200lp / mm, which can match 2.5μm pixel chips. When used for 1.1″ chips, its pixels can reach 23 million pixels, and the maximum optical distortion of the whole field of view is less than 1.0%. In addition, the present invention adopts a floating focus adjustment method, and its aperture can also be flexibly adjusted. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the optical module in the present invention.

[0022] Figure 2 It is an optical distortion curve diagram of the optical module in the present invention. DETAILED DESCRIPTION

[0023] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect.

[0024] In the description of the present invention, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "horizontal", etc. are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention.

[0025] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings, but this is not intended to limit the present invention.

[0027] like Figure 1 As shown, this embodiment provides a high-pixel and low-distortion optical lens, including an optical module, wherein the optical module is provided with a front group S1 with negative optical power, a middle group S2 with positive optical power, an aperture and a focusing group S3 with positive optical power in sequence from the object side to the image side;

[0028] The front group S1 includes a first lens G1 with positive power and a meniscus structure, a second lens G2 with negative power and a meniscus structure, and a third lens G3 with negative power and a meniscus structure;

[0029] The middle group S2 includes a fourth lens G4 with negative power and a biconcave structure, a fifth lens G5 with positive power and a biconvex structure, a sixth lens G6 with negative power and a meniscus structure, and a seventh lens G7 with positive power and a biconvex structure; wherein the fourth lens G4 and the fifth lens G5 are cemented into a first cemented lens group U1 with negative power, and the sixth lens G6 and the seventh lens G7 are cemented into a second cemented lens group U2 with positive power;

[0030] The focusing group includes an eighth lens G8 with positive focal power and a meniscus structure, a ninth lens G9 with negative focal power and a meniscus structure, a tenth lens G10 with negative focal power and a biconcave structure, an eleventh lens G11 with positive focal power and a biconvex structure, and a twelfth lens G12 with positive focal power and a biconvex structure; wherein the eighth lens G8 and the ninth lens G9 are cemented into a third cemented lens group U3 with negative focal power; the tenth lens G10 and the eleventh lens G11 are cemented into a fourth cemented lens group U4 with positive focal power;

[0031] The focal length of the optical module is f, the focal length of the front group is fS1, the focal length of the middle group is fS2, and the focal length of the focusing group is fS3, which satisfies the relationship: 1.20<|fS1 / f|<1.60, 1.20<|fS2 / f|<1.60, 1.20<|fS3 / f|<1.60.

[0032] Furthermore, the optical back focus BFL of the optical module and the focal length f of the optical module satisfy the relationship: |BFL / f|<1.50.

[0033] Furthermore, the half image height y' of the optical module and the focal length f of the optical module satisfy the relationship: |y' / f|<0.7.

[0034] Furthermore, the focal length of the first lens G1 is fG1, and the ratio of its focal length fG1 to the focal length f of the optical module satisfies the relationship: 2.80<|fG1 / f|<3.20; the focal length of the second lens G2 is fG2, and the ratio of its focal length fG2 to the focal length f of the optical module satisfies the relationship: 1.20<|fG2 / f|<1.80; the focal length of the third lens G3 is fG3, and the ratio of its focal length fG3 to the focal length f of the optical module satisfies the relationship: 1.80<|fG3 / f|<2.20.

[0035] Furthermore, the focal length of the first cemented lens group is fU1, and the ratio of the focal length fU1 to the focal length f of the optical module satisfies the relationship: 6.50<|fU1 / f|<7.00.

[0036] Furthermore, the focal length of the second cemented lens group is fU2, and the ratio of the focal length fU2 to the focal length f of the optical module satisfies the relationship: 1.00<|fU2 / f|<1.50.

[0037] Furthermore, the focal length of the third cemented lens group is fU3, and the ratio of the focal length fU3 to the focal length f of the optical module satisfies the relationship: 5.60<|fU3 / f|<6.40.

[0038] Furthermore, the focal length of the fourth cemented lens group is fU4, and the ratio of the focal length fU4 to the focal length f of the optical module satisfies the relationship: 52.00<|fU4 / f|<56.00.

[0039] Furthermore, the focal length of the twelfth lens G12 is fG12, and the ratio of the focal length fG12 to the focal length f of the optical module satisfies the relationship: 1.20<|fG12 / f|<1.60.

[0040] Furthermore, each lens is a spherical mirror, the diaphragm is an aperture diaphragm, and the aperture of the diaphragm is adjustable within the range of F2.8 to F16.

[0041] In this example, the optical module data is as follows:

[0042]

[0043]

[0044] In this example, the focal length f of the optical module is 16 mm, the maximum aperture is F#=2.8, and the focal length f of the front group S1 is S1 = -22.9mm, focal length f of center group S2 S2 =21.38mm, focal length of focusing group f S3 =23.8mm. Optical back focus BFL = 17.3mm, half image height y' = 8.8mm. The focal length of the first lens G1 is f G1 =48.6mm, the focal length of the second lens G2 is f G2 =-24.0mm, the focal length of the third lens G3 is f G3 =-33.8mm, the focal length of the first cemented lens group is f U1 =-108.5mm, the focal length of the second cemented lens group is f U2 =-21.9mm, the focal length of the third cemented lens group is f U3 =-98.1mm, the focal length of the fourth cemented lens group is f U4 =868.1mm, the focal length of the twelfth lens G12 is f G12 =23.6mm.

[0045] Each relation:

[0046] |f S1 / f|=1.43;|f S2 / f|=1.33;|f S3 / f|=1.49;

[0047] |BFL / f|=1.08; |y' / f|=0.55; |f G1 / f|=3.03;|fG2 / f|=1.50;

[0048] |f G3 / f|=2.11;|f U1 / f|=1.47;|f U2 / f|=6.78;|f U3 / f|=1.37;

[0049] |f U4 / f|=6.13;|f G12 / f|=54.26;

[0050] Satisfies the relationship:

[0051] 1.20<|f S1 / f|<1.60; 1.20<|f S2 / f|<1.60;

[0052] 1.20<|f S3 / f|<1.60; |BFL / f|<1.50; |y' / f|<0.7;

[0053] 2.80<|f G1 / f|<3.20; 1.20<|f G2 / f|<1.80;

[0054] 1.80<|f G3 / f|<2.20;6.50<|f U1 / f|<7.00;

[0055] 1.00<|f U2 / f|<1.50;5.60<|f U3 / f|<6.40;

[0056] 52.00<|f U4 / f|<56.00;1.20<|f G12 / f|<1.60.

[0057] Figure 2 The optical distortion curve of this embodiment is shown, and the maximum optical distortion in the whole field of view is less than 1.0%.

[0058] The above structure realizes an optical module with a focal length of 16mm, an image side F number of 2.8, and a maximum imaging surface of The highest resolution can reach 200lp / mm, which can match 2.5μm pixel chip. When the corresponding 1.1″ chip is used, its pixel can reach 23 million pixels, and the maximum optical distortion of the whole field of view is less than 1.0%. In addition, the floating focus adjustment method is adopted, and its aperture can also be flexibly adjusted.

[0059] The above description shows and describes several preferred embodiments of the present invention, but as mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not depart from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A high-pixel, low-distortion optical lens, characterized in that: The optical module comprises an optical module, wherein the optical module is provided with a front group S1 with negative optical power, a middle group S2 with positive optical power, an aperture and a focusing group S3 with positive optical power in sequence from the object side to the image side; The front group S1 includes a first lens G1 with positive focal power and a meniscus structure, a second lens G2 with negative focal power and a meniscus structure, and a third lens G3 with negative focal power and a meniscus structure; The middle lens group S2 includes a fourth lens G4 with negative focal power and a biconcave structure, a fifth lens G5 with positive focal power and a biconvex structure, a sixth lens G6 with negative focal power and a meniscus structure, and a seventh lens G7 with positive focal power and a biconvex structure; wherein the fourth lens G4 and the fifth lens G5 are cemented into a first cemented lens group U1 with negative focal power, and the sixth lens G6 and the seventh lens G7 are cemented into a second cemented lens group U2 with positive focal power; The focusing group includes an eighth lens G8 with positive focal power and a meniscus structure, a ninth lens G9 with negative focal power and a meniscus structure, a tenth lens G10 with negative focal power and a biconcave structure, an eleventh lens G11 with positive focal power and a biconvex structure, and a twelfth lens G12 with positive focal power and a biconvex structure; wherein the eighth lens G8 and the ninth lens G9 are cemented into a third cemented lens group U3 with negative focal power; and the tenth lens G10 and the eleventh lens G11 are cemented into a fourth cemented lens group U4 with positive focal power; The focal length of the optical module is f, the focal length of the front group is fS1, the focal length of the middle group is fS2, and the focal length of the focusing group is fS3, which satisfy the relationship: 1.20<|fS1 / f|<1.60, 1.20<|fS2 / f|<1.60, 1.20<|fS3 / f|<1.60; The optical back focus BFL of the optical module and the focal length f of the optical module satisfy the relationship: | BFL / f |<1.50; The half image height y' of the optical module and the focal length f of the optical module satisfy the relationship: | y' / f |<0.7; The focal length of the first lens G1 is fG1, and the ratio of its focal length fG1 to the focal length f of the optical module satisfies the relationship: 2.80<|fG1 / f|<3.20; the focal length of the second lens G2 is fG2, and the ratio of its focal length fG2 to the focal length f of the optical module satisfies the relationship: 1.20<|fG2 / f|<1.80; the focal length of the third lens G3 is fG3, and the ratio of its focal length fG3 to the focal length f of the optical module satisfies the relationship: 1.80<|fG3 / f|<2.20; The focal length of the first cemented lens group is fU1, and the ratio of the focal length fU1 to the focal length f of the optical module satisfies the relationship: 6.50<|fU1 / f|<7.00; The focal length of the second cemented lens group is fU2, and the ratio of the focal length fU2 to the focal length f of the optical module satisfies the relationship: 1.00<|fU2 / f|<1.50; The focal length of the third cemented lens group is fU3, and the ratio of the focal length fU3 to the focal length f of the optical module satisfies the relationship: 5.60<|fU3 / f|<6.40; The focal length of the fourth cemented lens group is fU4, and the ratio of the focal length fU4 to the focal length f of the optical module satisfies the relationship: 52.00<|fU4 / f|<56.00; The focal length of the twelfth lens G12 is fG12, and the ratio of the focal length fG12 to the focal length f of the optical module satisfies the relationship: 1.20<|fG12 / f|<1.

60.

2. The high-pixel, low-distortion optical lens according to claim 1, characterized in that: Each of the lenses is a spherical mirror, the diaphragm is an aperture diaphragm, and the aperture of the diaphragm is adjustable within the range of F2.8 to F16.

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