16k linear array camera, double telecentric linear scanning lens and optical system thereof

Abstract

The application relates to the technical field of machine vision lenses, and discloses a 16K linear array camera, a double-telecentric linear scanning lens and an optical system thereof. The optical system comprises a front group S1, an aperture T and a rear group S2 arranged in sequence from an object side to an image side. The front group S1 comprises a first lens G1 with positive refractive power, a second lens G2 with positive refractive power, a third lens G3 with positive refractive power and a fourth lens G4 with negative refractive power; and the rear group S2 comprises a fifth lens G5 with negative refractive power, a sixth lens G6 with positive refractive power, a seventh lens G7 with positive refractive power and an eighth lens G8 with positive refractive power. The optical system provided by the application can support a 16K, 5-micron large-target linear array camera, has the characteristics of low distortion, and the resolution of the largest imaging surface can reach 100 lp / mm or above.

Description

Technical Field

[0001] This invention relates to the field of machine vision lens technology, and in particular to a 16K line scan camera, a dual telecentric line scan lens, and its optical system. Background Technology

[0002] Machine vision is a rapidly developing branch of artificial intelligence. Simply put, machine vision uses machines to replace human eyes for measurement and judgment. A machine vision system uses an image acquisition device to convert the captured target into an image signal, which is then transmitted to a dedicated image processing system. Based on pixel distribution and information such as brightness and color, the signal is converted into a digital signal. The image system then performs various calculations on these signals to extract the target's features, and finally controls the actions of equipment on-site based on the judgment results.

[0003] The lens is one of the most crucial components in a machine vision inspection system. Line scan lenses, characterized by large target area and high precision, are widely used in scanning measurement fields, such as product measurement and defect detection in packaging printing, intelligent logistics, automotive manufacturing, and new energy industries. However, as the object distance changes, line scan lenses exhibit issues such as varying magnification and parallax. Furthermore, because the angle of light entering the lens differs depending on the object's position, line scan lenses cannot accurately reproduce details such as breaks and gaps in non-flat objects.

[0004] Therefore, traditional line scanning lenses no longer meet the application requirements of the industry, and it is necessary to further improve existing line scanning lenses to meet the needs of detection.

[0005] The above information is provided as background information only to aid in understanding this disclosure and does not constitute an assertion or admission that any of the above content can be used as prior art relative to this disclosure. Summary of the Invention

[0006] The purpose of this invention is to provide a 16K line scan camera, a dual telecentric line scan lens and its optical system, so as to solve or at least partially solve the technical problems existing in the prior art.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides an optical system for a low-distortion anti-shake lens, comprising a front group S1, an aperture T, and a rear group S2 arranged sequentially from the object side to the image side;

[0009] The front group S1 includes a first lens G1 with positive optical power, a second lens G2 with positive optical power, a third lens G3 with positive optical power, and a fourth lens G4 with negative optical power.

[0010] The rear group S2 includes a fifth lens G5 with negative optical power, a sixth lens G6 with positive optical power, a seventh lens G7 with positive optical power, and an eighth lens G8 with positive optical power.

[0011] The combined focal length of the front group S1 is f S1 The combined focal length of the rear group S2 is f. S2 f S1 f S2 The relation is satisfied: 0.7 < |f S1 / f S2 |<1.3; The half-image height y' of the optical system and f S2 The relation is satisfied: 0.2 < |y' / f S2 |<0.5.

[0012] Optionally, the third lens G3 and the fourth lens G4 form a cemented lens U1, and the focal length of the cemented lens U1 is f. U1 f U1 with f S1 The relation is satisfied: 0.3 < |f U1 / f S1 |<1.3;

[0013] The fifth lens G5 and the sixth lens G6 form a cemented lens U2, and the focal length of the cemented lens U2 is f. U2 f U2 with f S2 The relation is satisfied: 0.9 < |f U2 / f S2 |<1.9.

[0014] Optionally, the refractive index of the first lens G1 is n1, and the Abbe number is v1, where n1 and v1 satisfy the following relationship: 1.85 <n1<2.2,20<v1<30;

[0015] The refractive index of the second lens G2 is n2, and the Abbe number is v2. n2 and v2 satisfy the following relationship: 1.55 <n2<1.65,55<v2<70。

[0016] Optionally, the refractive index of the seventh lens G7 is n7, and the Abbe number is v7, where n7 and v7 satisfy the following relationship: 1.48 <n7<1.65,60<v7<82;

[0017] The refractive index of the eighth lens G8 is n8, and its Abbe number is v8. n8 and v8 satisfy the following relationship: 1.80 <n8<2.2,18<v8<30。

[0018] Optionally, the first lens G1 is a biconvex lens, and the second lens G2, the third lens G3 and the third lens G4 are meniscus lenses.

[0019] Optionally, the fifth lens G5 is a biconcave lens, the sixth lens G6 and the eighth lens G8 are biconvex lenses, and the seventh lens G7 is a meniscus lens.

[0020] Optionally, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, the fifth lens G5, the sixth lens G6, the seventh lens G7, the eighth lens G8, and the ninth lens G9 are all spherical lenses, and the optical axes of all the spherical lenses coincide.

[0021] Optionally, the aperture of the stop T is a circular aperture, and the center of the circular aperture is on the optical axis of the spherical lens.

[0022] Secondly, the present invention provides a dual telecentric linear scanning lens, including the optical system of a dual telecentric linear scanning lens as described above.

[0023] Thirdly, the present invention provides a 16K line scan camera equipped with a dual telecentric line scan lens, wherein the dual telecentric line scan lens adopts the dual telecentric line scan lens described above.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The optical system of the dual telecentric line scan lens provided by this invention has a dual telecentric structure, which can improve the shortcomings of ordinary line scan lenses in imaging, such as parallax and loss of imaging details. The optical system can support 16K, 5μm large target area line scan cameras, and has the characteristics of low distortion. The resolution of the maximum imaging surface can reach 100lp / mm and above. In addition, the optical system has a magnification of more than 0.7 times, which can detect tiny objects and is also suitable for application scenarios with high requirements for accuracy and field of view.

[0026] The present invention has other features and advantages, which will be apparent from or will be set forth in detail in the accompanying drawings and the following detailed description, which together serve to explain the particular principles of the invention. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the optical path structure of an optical system for a dual telecentric linear scanning lens provided in Embodiment 1 of the present invention.

[0029] Figure 2 This is an MTF curve diagram of an optical system for a dual telecentric linear scanning lens provided in Embodiment 1 of the present invention.

[0030] Figure 3 This is an optical distortion curve diagram of an optical system for a dual telecentric linear scanning lens provided in Embodiment 1 of the present invention.

[0031] Figure 4 This is a schematic diagram of the optical path structure of an optical system for a dual telecentric linear scanning lens provided in Embodiment 2 of the present invention.

[0032] Figure 5 This is an MTF curve diagram of an optical system for a dual telecentric linear scanning lens provided in Embodiment 2 of the present invention.

[0033] Figure 6 This is an optical distortion curve diagram of an optical system for a dual telecentric linear scanning lens provided in Embodiment 2 of the present invention. Detailed Implementation

[0034] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.

[0035] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0036] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.

[0037] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.

[0038] In this application, terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy or order relationship between these entities or operations.

[0039] Unless otherwise specified, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0040] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0041] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the purpose of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0042] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0043] Example 1:

[0044] Please see Figure 1 , Figure 1 This is a schematic diagram of the optical path structure of an optical system for a dual telecentric linear scanning lens provided in an embodiment of the present invention.

[0045] like Figure 1 As shown, the optical system includes:

[0046] It includes the front group S1, the aperture T, and the rear group S2, arranged sequentially from the object side to the image side;

[0047] Specifically, the front group S1 includes a first lens G1 with positive optical power, a second lens G2 with positive optical power, a third lens G3 with positive optical power, and a fourth lens G4 with negative optical power.

[0048] The rear group S2 includes a fifth lens G5 with negative optical power, a sixth lens G6 with positive optical power, a seventh lens G7 with positive optical power, and an eighth lens G8 with positive optical power.

[0049] The combined focal length of the front group S1 is f S1 The combined focal length of the rear group S2 is f. S2 f S1 f S2 The relation is satisfied: 0.7 < |f S1 / f S2 |<1.3; The half-image height y' of the optical system and f S2 The relation is satisfied: 0.2 < |y' / f S2 |<0.5.

[0050] In this embodiment, the lens structure of the front group S1 and the lens structure of the rear group S2 are relatively symmetrical, which is beneficial for the correction of transverse aberrations such as distortion and coma; the aperture T is set between the fourth lens G4 and the fifth lens G5 to form a double telecentric structure, and the aperture of the aperture T is a circular hole.

[0051] Furthermore, the third lens G3 and the fourth lens G4 form a cemented lens U1, and the focal length of the cemented lens U1 is f. U1 f U1 with f S1 The relation is satisfied: 0.3 < |f U1 / f S1 |<1.3;

[0052] The fifth lens G5 and the sixth lens G6 form a cemented lens U2, and the focal length of the cemented lens U2 is f. U2 f U2 with f S2 The relation is satisfied: 0.9 < |f U2 / f S2|<1.9。

[0053] The cemented lens U1 and the cemented lens U2 can correct chromatic aberration and field curvature, and the cemented surface of the cemented lens U2 can correct astigmatism.

[0054] Furthermore, the refractive index of the first lens G1 is n1, and the Abbe number is v1. n1 and v1 respectively satisfy the relational expressions: 1.85 < n1 < 2.2, 20 < v1 < 30; it can be understood that using a high refractive index material can reduce the curvature of the lens, thereby reducing high-order aberrations and lowering the tolerance sensitivity;

[0055] The refractive index of the second lens G2 is n2, and the Abbe number is v2. n2 and v2 respectively satisfy the relational expressions: 1.55 < n2 < 1.65, 55 < v2 < 70.

[0056] As Figure 1 shown, in this embodiment, the first lens G1 and the second lens G2 maintain a large interval. The first lens G1 selects a low Abbe number and a high-dispersion material, so that light rays with different wavelengths and different fields of view form different height differences on the cemented lens U1, which is beneficial to correcting the chromatic aberration and spherical aberration of the optical system and improving the imaging performance of the lens optical system.

[0057] Furthermore, the refractive index of the seventh lens G7 is n7, and the Abbe number is v7. n7 and v7 respectively satisfy the relational expressions: 1.48 < n7 < 1.65, 60 < v7 < 82; by satisfying the above relational expressions, the formation of chromatic aberration can be reduced, and the spherical aberration and coma can be better balanced;

[0058] The refractive index of the eighth lens G8 is n8, and the Abbe number is v8. n8 and v8 respectively satisfy the relational expressions: 1.80 < n8 < 2.2, 18 < v8 < 30. Using a high refractive index material can reduce the curvature of the lens, thereby reducing high-order aberrations and lowering the tolerance sensitivity.

[0059] Specifically, in this embodiment, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, the fifth lens G5, the sixth lens G6, the seventh lens G7, the eighth lens G8, and the ninth lens G9 are all spherical lenses, and the optical axes of all spherical lenses coincide; the center of the circular hole of the aperture stop T is on the above-mentioned optical axis. It can be understood that the aperture value of the aperture stop T needs to be adjusted correspondingly according to the specific application scenario.

[0060] More specifically, the first lens G1 is a biconvex lens, the second lens G2, the third lens G3, and the third lens G4 are meniscus lenses. The fifth lens G5 is a biconcave lens, the sixth lens G6 and the eighth lens G8 are biconvex lenses, and the seventh lens G7 is a meniscus lens.

[0061] Furthermore, to verify the performance of the above-mentioned optical system, specific application examples are given below for illustration:

[0062] In this application case, the relevant data of the optical system are shown in Table 1:

[0063] Table 1

[0064] surface Radius (mm) Thickness (mm) Refractive index Abbe number G1 front surface 359.7 20 2.0 25 G1 rear surface -1023.7 121.6 G2 front surface 56.5 15.3 1.60 65 G2 rear surface 176.6 3.2 G3 front surface 46.1 16.9 1.50 - G3 and G4 adhesive surfaces 499.2 9.7 1.75 - G4 rear surface 25.7 28.4 Aperture T ∞ 15.1 G5 front surface -35.5 4.0 1.70 - G5 and G6 adhesive surfaces 259.2 8.5 1.50 - G6 rear surface -37.5 26.9 G7 front surface -148.8 16.2 1.50 65 G7 rear surface -56.9 90.0 G8 front surface 558.1 18.0 2.0 25 G8 rear surface -340.4 157.0 Image /

[0065] It should be noted that in Table 1, "front surface" corresponds to... Figure 1 The left surface of the lens or lens group corresponds to the middle surface, while the rear surface corresponds to the middle surface. Figure 1 The right side surface of the corresponding lens or lens group; or it can be understood as: the object surface in Figure 1 On the left, the image plane (or image surface) is... Figure 1 On the right side, the surface closer to the object is called the "front surface", and the surface closer to the image is called the "back surface".

[0066] In this application case, the optical system is a dual telecentric structure with a working distance of 216mm, a magnification of 0.8x, and a half-image height y' = 41mm, meaning the maximum imaging area reaches Φ82mm, supporting 16K, 5-micron line scan cameras; the combined focal length of the front group S1 is f. S1 =153mm; the combined focal length of the rear group S2 is f S2 =122mm; Focal length f of cemented lens U1 U1 = -79mm; Focal length f of cemented lens U2 U2 = -195mm.

[0067] Substituting the above values ​​into the respective relations, we obtain:

[0068] |f S1 / f S2 |=1.254,|y' / f S2 |=0.336,|f U1 / f S1 |=0.516,|f U2 / f S2 |=1.598.

[0069] Therefore, the relevant relational expression in this embodiment is satisfied, namely:

[0070] 0.7<|f S1 / f S2 |<1.3, 0.2<|y' / f S2 |<0.5, 0.3<|f U1 / f S1 |<1.3, 0.9<|f U2 / f S2|<1.9.

[0071] Please continue to refer to this. Figure 2 and Figure 3 , Figure 2 This is an MTF curve diagram of an optical system for a dual telecentric linear scanning lens provided in an embodiment of the present invention. Figure 3 This is an optical distortion curve diagram of an optical system for a dual telecentric scanning lens provided in an embodiment of the present invention;

[0072] like Figure 2 As shown, experimental verification shows that MTF30 reaches 100 lp / mm, enabling uniform imaging of the optical system across the entire field of view. Figure 2 As shown, the distortion of this optical system is less than 0.02%.

[0073] This embodiment provides an optical system for a dual telecentric line scan lens, which can improve upon the shortcomings of ordinary line scan lenses, such as parallax and loss of imaging details. This optical system can support 16K, 5μm large target area line scan cameras, and features low distortion. The maximum resolution of the imaging surface can reach 100lp / mm or higher. Furthermore, this optical system has a magnification of more than 0.7 times, which can detect tiny objects and is also suitable for applications with high requirements for accuracy and field of view.

[0074] Example 2:

[0075] It includes the front group S1, the aperture T, and the rear group S2, arranged sequentially from the object side to the image side;

[0076] Specifically, the front group S1 includes a first lens G1 with positive optical power, a second lens G2 with positive optical power, a third lens G3 with positive optical power, and a fourth lens G4 with negative optical power.

[0077] The rear group S2 includes a fifth lens G5 with negative optical power, a sixth lens G6 with positive optical power, a seventh lens G7 with positive optical power, and an eighth lens G8 with positive optical power.

[0078] The combined focal length of the front group S1 is f S1 The combined focal length of the rear group S2 is f. S2 f S1 f S2 The relation is satisfied: 0.7 < |f S1 / f S2 |<1.3; The half-image height y' of the optical system and f S2 The relation is satisfied: 0.2 < |y' / f S2 |<0.5.

[0079] In this embodiment, the lenses of the front group S1 and the lenses of the rear group S2 are relatively symmetrical in structure, which is beneficial to the correction of lateral aberrations such as distortion and coma; the aperture stop T is arranged between the fourth lens G4 and the fifth lens G5 to form a double telecentric structure, and the aperture of the aperture stop T is a circular hole.

[0080] Further, the third lens G3 and the fourth lens G4 form a cemented lens U1, and the focal length of the cemented lens U1 is f U1 , f U1 and f S1 satisfy the relational expression: 0.3 < |f U1 / f S1 | < 1.3;

[0081] The fifth lens G5 and the sixth lens G6 form a cemented lens U2, and the focal length of the cemented lens U2 is f U2 , f U2 and f S2 satisfy the relational expression: 0.9 < |f U2 / f S2 | < 1.9.

[0082] The cemented lens U1 and the cemented lens U2 can correct chromatic aberration and field curvature, and the cemented surface of the cemented lens U2 can correct astigmatism.

[0083] Further, the refractive index of the first lens G1 is n1, and the Abbe number is v1. n1 and v1 respectively satisfy the relational expressions: 1.85 < n1 < 2.2, 20 < v1 < 30; it can be understood that using a high refractive index material can reduce the curvature of the lens, thereby reducing high-order aberrations and reducing the tolerance sensitivity;

[0084] The refractive index of the second lens G2 is n2, and the Abbe number is v2. n2 and v2 respectively satisfy the relational expressions: 1.55 < n2 < 1.65, 55 < v2 < 70.

[0085] As Figure 1 shown, in this embodiment, the first lens G1 and the second lens G2 maintain a relatively large interval. The first lens G1 selects a low Abbe number and a high dispersion material, so that light rays with different wavelengths and different fields of view form different height differences on the cemented lens U1, which is beneficial to correcting the chromatic aberration and spherical aberration of the optical system and improving the imaging performance of the lens optical system.

[0086] Further, the refractive index of the seventh lens G7 is n7, and the Abbe number is v7. n7 and v7 respectively satisfy the relational expressions: 1.48 < n7 < 1.65, 60 < v7 < 82; by satisfying the above relational expressions, the formation of chromatic aberration can be reduced, and spherical aberration and coma can be better balanced;

[0087] The refractive index of the eighth lens G8 is n8, and the Abbe number is v8. n8 and v8 respectively satisfy the relational expressions: 1.80 < n8 < 2.2, 18 < v8 < 30. Using a high refractive index material can reduce the curvature of the lens, thereby reducing high-order aberrations and lowering the tolerance sensitivity.

[0088] Specifically, in this embodiment, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, the fifth lens G5, the sixth lens G6, the seventh lens G7, the eighth lens G8, and the ninth lens G9 are all spherical lenses, and the optical axes of all the spherical lenses coincide; the center of the circular hole of the aperture stop T is on the above-mentioned optical axis. It can be understood that the aperture value of the aperture stop T needs to be adjusted correspondingly according to the specific application scenario.

[0089] More specifically, the first lens G1 is a biconvex lens, and the second lens G2, the third lens G3, and the fourth lens G4 are meniscus lenses. The fifth lens G5 is a biconcave lens, the sixth lens G6 and the eighth lens G8 are biconvex lenses, and the seventh lens G7 is a meniscus lens.

[0090] Furthermore, to verify the performance of the above light ray system, the following specific application cases are given for illustration:

[0091] In this application case, the relevant data of the optical system are specifically shown in Table 2 as follows:

[0092] Table 2

[0093] surface Radius (mm) Thickness (mm) Refractive index Abbe number G1 front surface 581.0 17.7 1.85 25 G1 rear surface -331.8 7.2 G2 front surface 142.2 16.0 1.60 65 G2 rear surface 415.4 58.3 G3 front surface 40.1 20.1 1.50 - G3 and G4 adhesive surfaces 200.2 11.1 1.75 - G4 rear surface 26.8 28.2 Aperture T ∞ 20.9 G5 front surface -35.6 4.0 1.69 - G5 and G6 adhesive surfaces 425.1 9.2 1.50 - G6 rear surface -43.2 15.0 G7 front surface -146.9 9.6 1.60 65 G7 rear surface -52.7 124.6 G8 front surface 412.4 18.0 1.85 25 G8 rear surface -370.7 177.6 Image /

[0094] It should be noted that in Table 1, the "front surface" corresponds to Figure 4 the left surface of the corresponding lens or lens group, and the "rear surface" corresponds to Figure 4 the right surface of the corresponding lens or lens group; or it can be understood that: the object side is on the Figure 4 left side, and the image side (or image plane) is on the Figure 1 right side. The surface closer to the object side is the "front surface", and the surface closer to the image side is the "rear surface".

[0095] In this application case, the optical system is a double telecentric structure, its working distance is 199 mm, the magnification reaches 1 times, the semi-image height y' = 41 mm, that is, the maximum imaging surface reaches Φ82 mm; among them, the combined focal length of the front group S1 is f S1 = 138 mm; the combined focal length of the rear group S2 is f S2 = 135 mm; the focal length of the cemented lens group U1 is f U1 = -159 mm; the focal length of the cemented lens group U2 is f U2 = -155 mm.

[0096] Substituting the above values ​​into the respective relations, we obtain:

[0097] |f S1 / f S2 |=1.022,|y' / f S2 |=0.304,|f U1 / f S1 |=1.123,|f U2 / f S2 |=1.148.

[0098] Therefore, the relevant relational expression in this embodiment is satisfied, namely:

[0099] 0.7<|f S1 / f S2 |<1.3, 0.2<|y' / f S2 |<0.5, 0.3<|f U1 / f S1 |<1.3, 0.9<|f U2 / f S2 |<1.9.

[0100] Please continue to refer to this. Figure 5 and Figure 6 , Figure 5 This is an MTF curve diagram of an optical system for a dual telecentric linear scanning lens provided in Embodiment 2 of the present invention. Figure 6 This is an optical distortion curve diagram of an optical system for a dual telecentric scanning lens provided in Embodiment 2 of the present invention;

[0101] like Figure 5 As shown, experimental verification shows that MTF30 reaches 100 lp / mm, enabling uniform imaging of the optical system across the entire field of view, supporting 16K, 5-micron line scan cameras. Figure 6 As shown, the distortion of this optical system is less than 0.02%.

[0102] This embodiment provides an optical system for a dual telecentric line scan lens, which can improve upon the shortcomings of ordinary line scan lenses, such as parallax and loss of imaging details. This optical system can support 16K, 5μm large target area line scan cameras, and features low distortion. The maximum resolution of the imaging surface can reach 100lp / mm or higher. Furthermore, this optical system has a magnification of more than 0.7 times, which can detect tiny objects and is also suitable for applications with high requirements for accuracy and field of view.

[0103] Example 3:

[0104] This embodiment provides a dual telecentric linear scanning lens, including the optical system of a dual telecentric linear scanning lens as described in Embodiment 1 or Embodiment 2.

[0105] Since the optical system has been described in detail in the above embodiments, it will not be repeated in this embodiment.

[0106] In addition, based on the above technical concept, this embodiment also provides a 16K line scan camera equipped with a dual telecentric line scan lens, which adopts the dual telecentric line scan lens described above.

[0107] In summary, this embodiment realizes a 16K line scan camera and its dual telecentric line scan lens, with a maximum imaging surface resolution of 100 lp / mm or higher, and a magnification of more than 0.7 times, which can detect fine objects and is also suitable for application scenarios with high requirements for accuracy and field of view.

[0108] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An optical system of a dual-telecentric line-scan lens, characterized by, The optical system comprises a front group S1, an aperture stop T and a rear group S2 arranged in sequence from the object side to the image side; the optical system comprises 8 lenses with optical power in total; The front group S1 comprises a first lens G1 with positive optical power, a second lens G2 with positive optical power, a third lens G3 with positive optical power and a fourth lens G4 with negative optical power; The rear group S2 comprises a fifth lens G5 with negative optical power, a sixth lens G6 with positive optical power, a seventh lens G7 with positive optical power and an eighth lens G8 with positive optical power; The first lens G1 is a double convex lens, the second lens G2, the third lens G3 and the third lens G4 are all meniscus lenses with convex object side and concave image side, the fifth lens G5 is a double concave lens, the sixth lens G6 and the eighth lens G8 are double convex lenses, and the seventh lens G7 has a concave object side and a convex image side; The combined focal length of the front group S1 is f S1 , and the combined focal length of the rear group S2 is f S2 , f S1 , f S2 satisfy the relationship: 0.7 < |f S1 / f S2 | < 1.3; and the half-height y' of the optical system and f S2 satisfy the relationship: 0.2 < |y' / f S2 | < 0.

5.

2. The optical system of claim 1, wherein, The third lens G3 and the fourth lens G4 constitute a cemented lens U1, and the focal length of the cemented lens U1 is f U1 , f U1 and f S1 satisfy the relationship: 0.3<|f U1 / f S1 |<1.3; The fifth lens G5 and the sixth lens G6 constitute a cemented lens U2, and the focal length of the cemented lens U2 is f U2 , f U2 , and f S2 satisfy the relationship: 0.9 < |f U2 / f S2 | < 1.

9.

3. An optical system of a dual-telecentric line-scan lens according to claim 2, wherein, The refractive index of the first lens G1 is n1, and the Abbe number is v1, and n1 and v1 satisfy the relationship 1.85 < n1 < 2.2 and 20 < v1 < 30 respectively; The refractive index of the second lens G2 is n2, and the Abbe number is v2, and n2 and v2 satisfy the relationship 1.55 < n2 < 1.65 and 55 < v2 < 70 respectively.

4. The optical system of claim 2, wherein, The refractive index of the seventh lens G7 is n7, and the Abbe number is v7, and n7 and v7 satisfy the relationship 1.48 < n7 < 1.65 and 60 < v7 < 82 respectively. The refractive index of the eighth lens G8 is n8, and the Abbe number is v8, and n8 and v8 satisfy the relationship 1.80 < n8 < 2.2 and 18 < v8 < 30 respectively.

5. The optical system of a double telecentric line-scan lens according to claim 3, wherein, The first lens G1 is a double convex lens, and the second lens G2, the third lens G3 and the third lens G4 are meniscus lenses.

6. An optical system of a dual-telecentric line-scan lens according to claim 4, wherein, The fifth lens G5 is a double concave lens, the sixth lens G6 and the eighth lens G8 are double convex lenses, and the seventh lens G7 is a meniscus lens.

7. The optical system of claim 1, wherein, The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, the fifth lens G5, the sixth lens G6, the seventh lens G7, the eighth lens G8 and the ninth lens G9 are all spherical lenses, and the optical axes of all the spherical lenses coincide.

8. The optical system of a double telecentric line-scan lens according to claim 7, characterized in that The aperture of the aperture stop T is a circular hole, and the center of the circular hole is on the optical axis of the spherical lens.

9. A dual-telecentric line-scan lens characterized by, The optical system comprises a double telecentric line scan lens as claimed in any one of claims 1-8.

10. A 16K linear array camera equipped with a dual telecentric line scan lens characterized in that, The double telecentric line scan lens adopts the double telecentric line scan lens as claimed in claim 9.

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