Long-working-distance 10-time large NA telecentric microscope lens and optical system thereof

Abstract

The invention relates to the technical field of imaging optical system and device design, and discloses a long-working-distance 10-time large NA telecentric microscope lens and an optical system thereof. The optical system comprises a front group S1 with positive focal power, a diaphragm T and a rear group S2 with negative focal power which are sequentially arranged from an object side to an image side, and the diaphragm T is placed at the focal point of the front group S1 to form an object side telecentric framework; the maximum outer diameters of all the lenses in the front group S1 are the same, and the maximum outer diameters of all the lenses in the rear group S2 are the same; the working distance WD and the numerical aperture NA of the optical system meet the relational expression that NA * WD is smaller than or equal to 17. According to the optical system provided by the invention, the amplification factor is 10 times, and the microscope-level resolution ratio of 1.5 microns can be realized; the outer diameters of the front and rear groups of lenses are the same, so that the coaxiality is ensured after assembling and forming, and the imaging quality of the lens is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of imaging optical systems and device design, and particularly relates to a telecentric microscope lens with a long working distance, 10 times magnification, and a large numerical aperture (NA) and its optical system. Background Art

[0002] With the rapid development of technologies in the machine vision industry, the requirements for lenses by vision inspection systems are getting higher and higher. For microscopic vision inspection applications, such as in the fields of semiconductor and ITO micro-region inspection, the demand for telecentric lenses with a long working distance and a higher numerical aperture (NA) is gradually increasing. Currently, under the application conditions of high magnification and high numerical aperture, a configuration of a microscope objective lens combined with a tube lens is generally selected. On the one hand, most microscope objective lenses have a short working distance and a relatively large size of the tube lens, which will face many difficulties in use. On the other hand, due to the non-telecentric design, problems such as different magnification ratios caused by changes in the object distance and parallax exist.

[0003] Currently, there are very few telecentric lenses with a long working distance and a large numerical aperture (NA) in the domestic market. Increasing either the working distance or the numerical aperture (NA) will increase the design difficulty and the difficulties in production and assembly. For example, the Chinese patent with the patent number "CN201910523470.9" provides a telecentric lens with a magnification of 4 times; another example is the Chinese patent with the patent number "CN202210789365.1", which provides a high-magnification, long-working-distance, coaxial illumination telecentric optical system and lens, but their corresponding object-side numerical apertures (NA) are lacking.

[0004] In summary, there is an urgent need in this field for a telecentric microscope lens with a long working distance and a large numerical aperture (NA) to meet the requirements of precise inspection in machine vision microscopic systems.

[0005] The above information is given as background information only to assist in understanding the present disclosure, and it is not determined or admitted whether any of the above content can be used as prior art relative to the present disclosure. Summary of the Invention

[0006] The purpose of the present invention is to provide a telecentric microscope lens with a long working distance, 10 times magnification, and a large numerical aperture (NA) and its optical system to solve or at least partially solve the technical problems existing in the prior art.

[0007] To achieve this purpose, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides an optical system for a long working distance 10x large NA telecentric microscope lens, comprising a front group S1 with positive optical power, a stop T, and a rear group S2 with negative optical power, which are sequentially arranged from the object side to the image side. The stop T is placed at the focal point of the front group S1 to form an object-side telecentric structure; wherein, the maximum outer diameters of all the lenses in the front group S1 are the same, and the maximum outer diameters of all the lenses in the rear group S2 are the same;

[0009] 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 and f S2 satisfy the relationship: 4 < |f S1 / f S2 | < 6;

[0010] The working distance of the optical system is WD, and the numerical aperture is NA. WD and NA satisfy the relationship: NA × WD ≤ 17.

[0011] Optionally, 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 negative optical power, a fourth lens G4 with positive optical power, 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; wherein, the third lens G3 and the fourth lens G4 form a first cemented lens U1, and the fifth lens G5 and the sixth lens G6 form a second cemented lens U2;

[0012] The focal length of the first lens G1 is f1, and f1 and f S1 satisfy the relationship: 1.5 < |f1 / f S1 | < 2.5;

[0013] The focal length of the second lens G2 is f2, and f2 and f1 satisfy the relationship: 0.75 < |f1 / f2| < 1.25;

[0014] The focal length of the first cemented lens U1 is f U1 , f U1 and f S1 satisfy the relationship: |f S1 / f U1 | < 0.1;

[0015] The focal length of the second cemented lens U2 is f U2 , f U2 and f S1 satisfy the relationship: 1.4 < |f U2 / f S1 | < 2.1;

[0016] The focal length of the seventh lens G7 is f7, and f7 and f S1 satisfy the relational expression: 2.5 < |f7 / f S1 | < 3.2;

[0017] The focal length of the eighth lens G8 is f8, and f8 and f S1 satisfy the relational expression: 1.6 < |f8 / f S1 | < 2.4.

[0018] Optionally, the rear group S2 includes a ninth lens G9 with a negative optical power, a tenth lens G10 with a negative optical power, and an eleventh lens G11 with a positive optical power; among them, the tenth lens G10 and the eleventh lens G11 form a third cemented lens U3;

[0019] The focal length of the ninth lens G9 is f9, and the f9 and the f S2 satisfy the relational expression: 1 < |f9 / f S2 | < 1.6;

[0020] The focal length of the third cemented lens U3 is f U3 , f U3 and f S2 satisfy the relational expression: 4.9 < |f U3 / f S2 | < 5.7.

[0021] 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, the ninth lens G9, the tenth lens G10, and the eleventh lens G11 are all spherical lenses, and the optical axes of all the spherical lenses are on a predetermined optical axis.

[0022] Optionally, the first lens G1 and the third lens G3 are both meniscus lenses, the second lens G2, the fourth lens G4, the sixth lens G6, the seventh lens G7, and the eleventh lens G11 are all biconvex lenses, the fifth lens G5 and the tenth lens G10 are both biconcave lenses, and the ninth lens G9 is a meniscus lens or a plano - concave lens.

[0023] Optionally, the materials of the second lens G2, the fourth lens G4, and the sixth lens G6 are all low - dispersion crown glasses, and the material of the eighth lens G8 is a high - dispersion flint glass.

[0024] Optionally, the maximum outer diameter of all the lenses in the front group S1 is set to Φ36 mm, and the maximum outer diameter of all the lenses in the rear group S2 is set to Φ8 mm.

[0025] Optionally, a beam - splitting prism P is also arranged between the front group S1 and the aperture T, the beam - splitting prism P is a semi - transparent and semi - reflective prism, and the rear group S2 is arranged on the refraction path of the beam - splitting prism P;

[0026] A coaxial illumination light source or an imaging component is also provided on the reflection path of the beam splitter prism P.

[0027] Optionally, the aperture of the aperture stop T is a circular hole, and the center of the circular hole is on the predetermined optical axis.

[0028] In a second aspect, the present invention provides a long working distance 10x large NA telecentric microscope lens, including the optical system of a long working distance 10x large NA telecentric microscope lens as described above.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The optical system of the long working distance 10x large NA telecentric microscope lens provided by the present invention is designed with object-side telecentricity. With a long working distance of 58 mm, the numerical aperture NA can reach 0.25, and the magnification is 10 times, thus achieving a resolution of 1.5 microns at the microscope level; the outer diameter sizes of the front group and the rear group of lenses are the same, which is beneficial to ensuring the coaxiality after assembly and improving the imaging quality of the lens.

[0031] The present invention has other characteristics and advantages, which will be obvious from the accompanying drawings incorporated herein and the subsequent detailed description, or will be described in detail in the accompanying drawings incorporated herein and the subsequent detailed description, and these accompanying drawings and detailed description are used together to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0033] Figure 1 It is a schematic structural diagram of the optical system of a long working distance 10x large NA telecentric microscope lens provided by an embodiment of the present invention.

[0034] Figure 2 It is an optical path diagram of the optical system of a long working distance 10x large NA telecentric microscope lens provided by an embodiment of the present invention.

[0035] Figure 3 It is an object-side MTF diagram of the optical system of a long working distance 10x large NA telecentric microscope lens provided by an embodiment of the present invention.

[0036] Figure 4It is the distortion diagram of the optical system of a long working distance 10x large NA telecentric microscope lens provided by an embodiment of the present invention. Detailed implementation manners

[0037] To describe in detail the possible application scenarios, technical principles, specific implementable solutions, achievable purposes and effects of the present application, etc., the following will be described in detail in conjunction with the listed specific embodiments and with reference to the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present application, so they are only examples and cannot be used to limit the protection scope of the present application.

[0038] Referring to "embodiments" herein means that the specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The term "embodiment" appearing in various positions in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or relevance to other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0039] Unless otherwise defined, the meanings of the technical terms used herein are the same as those commonly understood by those skilled in the technical field to which the present application belongs; the use of the relevant terms herein is only for describing specific embodiments and is not intended to limit the present application.

[0040] In the description of the present application, the phrase "and / or" is an expression used to describe the logical relationship between objects, indicating that there can be three relationships, for example, A and / or B, which means: there is A, there is B, and there is both A and B at the same time. In addition, the character " / " in this article generally represents an "or" logical relationship between the associated objects before and after.

[0041] In the present application, terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual quantity, primary or secondary, or order relationship between these entities or operations.

[0042] Without more limitations, in the present application, the expressions such as "including", "comprising", "having" or other similar expressions used in the statements are intended to cover non-exclusive inclusion. These expressions do not exclude that there may be other elements in the process, method or product including the said elements, so that the process, method or product including a series of elements may not only include those defined elements, but also include other elements not explicitly listed, or also include elements inherent to this process, method or product.

[0043] Similar to the understanding in the "Examination Guidelines", in this application, expressions such as "greater than", "less than", "exceeding", etc. are understood as not including the base number; expressions such as "above", "below", "within", etc. are understood as including the base number. In addition, in the description of the embodiments of this application, the meaning of "multiple" is two or more (including two), and similar expressions related to "many", such as "multiple groups", "multiple times", etc., are understood in this way unless otherwise specifically limited.

[0044] In the description of the embodiments of this application, the spatially related expressions used, such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the specific embodiment or the drawings. It is only for the convenience of describing the specific embodiments of this application or for the reader to understand, rather than indicating or implying 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, it should not be understood as a limitation to the embodiments of this application.

[0045] Unless otherwise clearly specified or limited, in the description of the embodiments of this application, the terms such as "installed", "connected", "connected", "fixed", "set", etc. should be understood in a broad sense. For example, the "connection" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection, or a communication connection; it can be directly connected, or indirectly connected through an intermediate medium; it can be the communication inside two components or the interaction relationship between two components. For those skilled in the art to which this application belongs, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0046] Embodiment 1:

[0047] Please refer to Figure 1 and Figure 2 , Figure 1 which are the structural schematic diagrams of an optical system of a long working distance 10x large NA telecentric microscope lens provided by the embodiments of the present invention, Figure 2 and

[0048] are the optical path diagrams of an optical system of a long working distance 10x large NA telecentric microscope lens provided by the embodiments of the present invention. Figure 1 As

[0049] A front group S1 with positive refractive power, a diaphragm T, and a rear group S2 with negative refractive power are sequentially arranged from the object side to the image side. The diaphragm T is placed at the focal point of the front group S1 to form an object-side telecentric structure. Among them, the maximum outer diameters of all lenses in the front group S1 are the same, and the maximum outer diameters of all lenses in the rear group S2 are the same;

[0050] 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 and f S2 satisfy the relationship: 4 < |f S1 / f S2 | < 6;

[0051] The working distance of the optical system is WD, and the numerical aperture is NA. WD and NA satisfy the relationship: NA × WD ≤ 17.

[0052] In this embodiment, the front group S1 has positive refractive power and the rear group S2 has negative refractive power. There is a certain distance between them, which is beneficial to correcting the field curvature of the system and improving the consistency of imaging quality;

[0053] Preferably, in this embodiment, the maximum outer diameters of the lenses in the front group S1 are all set to Φ36 mm, and the maximum outer diameters of the lenses in the rear group S2 are all set to Φ8 mm. Using a unified outer diameter for the front and rear groups is beneficial to the design, processing of the mechanical structure, and also beneficial to the assembly and debugging of the lenses, ensuring coaxiality and improving the imaging quality of the lens.

[0054] Specifically, the front group S1 includes a first lens G1 with positive refractive power, a second lens G2 with positive refractive power, a third lens G3 with negative refractive power, a fourth lens G4 with positive refractive power, 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; among them, the third lens G3 and the fourth lens G4 form a first cemented lens U1, and the fifth lens G5 and the sixth lens G6 form a second cemented lens U2;

[0055] The focal length of the first lens G1 is f1, and f1 and f S1 satisfy the relationship: 1.5 < |f1 / f S1 | < 2.5; The first lens G1 has a structure that tends to bend towards the object surface, aiming to reduce spherical aberration and chromatic aberration;

[0056] The focal length of the second lens G2 is f2, and f2 and f1 satisfy the relationship: 0.75 < |f1 / f2| < 1.25; The second lens G2 shares the ability of the first lens G1 to deflect light, alleviates the incident angle of light passing through the lens, and is beneficial to reducing the tolerance sensitivity and assembly difficulty;

[0057] The focal length of the first cemented lens U1 is f U1 , f U1 and f S1 satisfy the relation: |f S1 / f U1 | < 0.1;

[0058] The focal length of the second cemented lens U2 is f U2 , f U2 and f S1 satisfy the relation: 1.4 < |f U2 / f S1 | < 2.1;

[0059] The focal length of the seventh lens G7 is f7, and f7 and f S1 satisfy the relation: 2.5 < |f7 / f S1 | < 3.2;

[0060] The focal length of the eighth lens G8 is f8, and f8 and f S1 satisfy the relation: 1.6 < |f8 / f S1 | < 2.4.

[0061] Preferably, the second lens G2, the fourth lens G4, and the sixth lens G6 are all low-dispersion crown glasses, and the material of the eighth lens G8 is high-dispersion flint glass;

[0062] In this embodiment, by placing two adjacent doublet achromatic lenses in the front group S1 and reasonably matching and combining the optical powers and materials of each lens, the chromatic aberration and chromatic spherical aberration of the system can be effectively corrected; the two doublet lenses are arranged in the form of negative and positive lenses, which is beneficial to correcting spherical aberration and field curvature; the light passes through the first cemented lens U1 nearly parallelly, and its cemented surface can correct the astigmatism and higher-order aberrations of the optical system; the sixth lens G6 to the eighth lens G8 all have positive optical powers, which can reduce the bending degree of the lens surface and form smaller spherical aberration.

[0063] Furthermore, the rear group S2 includes a ninth lens G9 with negative optical power, a tenth lens G10 with negative optical power, and an eleventh lens G11 with positive optical power; wherein, the tenth lens G10 and the eleventh lens G11 form a third cemented lens U3;

[0064] The focal length of the ninth lens G9 is f9, and the f9 and the f S2 satisfy the relation: 1 < |f9 / f S2 | < 1.6;

[0065] The focal length of the third cemented lens U3 is f U3 , f U3 and f S2 satisfy the relation: 4.9 < |fU3 / f S2 |<5.7; The third cemented lens U3 can compensate for the chromatic aberration of the front group S1 while also being beneficial to the correction of distortion.

[0066] As a preferred 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, the ninth lens G9, the tenth lens G10, and the eleventh lens G11 are all spherical lenses. Preferably, the first lens G1 to the eleventh lens G11 are all spherical lenses, which have good processability; in this embodiment, the optical axes of all spherical lenses are on the predetermined optical axis ( Figure 1 the dotted line shown).

[0067] In this embodiment, the aperture of the diaphragm T is a circular hole, and the center of the circular hole is on the predetermined optical axis. It can be understood that the aperture value of the diaphragm T needs to be adjusted correspondingly according to the specific application scenario.

[0068] Specifically, the first lens G1 and the third lens G3 are both meniscus lenses, the second lens G2, the fourth lens G4, the sixth lens G6, the seventh lens G7, and the eleventh lens G11 are all biconvex lenses, the fifth lens G5 and the tenth lens G10 are both biconcave lenses, and the ninth lens G9 is a meniscus lens or a plano-concave lens.

[0069] As an alternative embodiment, a beam splitter prism P is further provided between the front group S1 and the diaphragm T. The beam splitter prism P is a semi-transmissive and semi-reflective prism, and the rear group S2 is disposed on the refraction path of the beam splitter prism P;

[0070] A coaxial illumination light source or an imaging component is further provided on the reflection path of the beam splitter prism P.

[0071] To verify whether the above optical system meets the design purpose, the following is a specific application example given according to the above settings of this embodiment:

[0072] In this application example, the data of each lens of the optical system are shown in Table 1 below:

[0073] Table 1

[0074]

[0075]

[0076] It should be noted that in Table 1, "front surface" corresponds to Figure 1 the left surface of the corresponding lens or lens group in Figure 1 ; or it can be understood that: the object side is on the Figure 1 left side, and the image side (or image plane) is on theFigure 1 On the right side, the surface closer to the object side is the "front surface", and the surface closer to the image side is the "back surface".

[0077] In this application example, the combined focal length of the front group S1 is f S1 = 46 mm; the combined focal length of the rear group S2 is f S2＝ -9 mm; the focal length of the first lens G1 is f1 = 94 mm; the focal length of the second lens G2 is f2 = 93 mm; the focal length f of the first cemented lens U1 U1 = -1536 mm; the focal length f of the second cemented lens U2 U2 = -80 mm; the focal length of the seventh lens G7 is f7 = 130 mm; the focal length of the eighth lens G8 is f8 = 91 mm; the focal length of the ninth lens G9 is f9 = -13 mm; the focal length f of the third cemented lens U3 U3 = -50 mm;

[0078] The optical path diagram of this optical system is as Figure 2 shown.

[0079] Please refer to Figure 3 and Figure 4 , Figure 3 which is the object-side MTF (Modulation Transfer Function) curve diagram of the optical system of a long working distance 10x large NA telecentric microscope lens provided in the first embodiment of the present invention, Figure 4 and is the distortion diagram of the optical system of a long working distance 10x large NA telecentric microscope lens provided in the first embodiment of the present invention;

[0080] As Figure 3 and Figure 4 shown, the optical parameters of this optical system are as follows:

[0081] Table 2

[0082] Working distance WD > 58 mm Numerical aperture NA 0.25 Object-image distance 263 mm Resolution 1.5 microns Magnification 10x Maximum field of view Φ1.1 mm Telecentricity <0.1° Distortion 0.02％

[0083] In Table 2, the calculation formula for the resolution is 0.65 * λ / NA, where λ is the wavelength.

[0084] In summary, compared with the prior art, the optical system of a long working distance 10x large NA telecentric microscope lens provided in this embodiment has the following beneficial effects:

[0085] Adopting an object-side telecentric design, with a long working distance of 58 mm, the numerical aperture NA can reach 0.25, and the magnification is 10 times, thus achieving a resolution of 1.5 microns at the microscope level;

[0086] All lenses are spherical lenses, so they have good processability;

[0087] The outer diameters of the lenses of the front group S1 and the rear group S2 are made uniform respectively, which is beneficial to assembly and forming, ensures coaxiality, and improves the imaging quality of the lens.

[0088] Embodiment 2:

[0089] This embodiment provides a 10x large NA telecentric microscopic lens with a long working distance, including the optical system of a 10x large NA telecentric microscopic lens as described in Embodiment 1.

[0090] Based on the relatively detailed description of the optical system in the above embodiment, it will not be elaborated in this embodiment.

[0091] Aiming at the deficiencies of the prior art, this embodiment provides a 10x telecentric microscopic lens with a long working distance and a large numerical aperture NA, which can meet the requirements of precise detection of the machine vision microscopic system.

[0092] As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An optical system of a long working distance 10x large NA telecentric microscope lens, characterized in that, It includes a front group S1 with positive refractive power, a diaphragm T, and a rear group S2 with negative refractive power, which are arranged in sequence from the object side to the image side. The diaphragm T is placed at the focal point of the front group S1 to form an object-side telecentric structure. Among them, the maximum outer diameters of all the lenses in the front group S1 are the same, and the maximum outer diameters of all the lenses in the rear group S2 are the same. 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 and f S2 satisfy the relationship: 4 < |f S1 / f S2 | < 6; The working distance of the optical system is WD, and the numerical aperture is NA. WD and NA satisfy the relationship: NA×WD≤17.

2. The optical system of a long working distance 10x large NA telecentric microscope lens according to claim 1, characterized in that, The front group S1 includes a first lens G1 with positive refractive power, a second lens G2 with positive refractive power, a third lens G3 with negative refractive power, a fourth lens G4 with positive refractive power, 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. Among them, the third lens G3 and the fourth lens G4 form a first cemented lens U1, and the fifth lens G5 and the sixth lens G6 form a second cemented lens U2. The focal length of the first lens G1 is f1, and f1 and f S1 satisfy the relational expression: 1.5 < |f1 / f S1 | < 2.5; The focal length of the second lens G2 is f2, and f2 and f1 satisfy the relationship: 0.75<|f1 / f2|<1.

25. The focal length of the first cemented lens U1 is f U1 , f U1 and f S1 satisfy the relationship: |f S1 / f U1 |< 0.1; The focal length of the second cemented lens U2 is f U2 , f U2 and f S1 satisfy the relational expression: 1.4 < |f U2 / f S1 | < 2.1; The focal length of the seventh lens G7 is f7, and f7 and f S1 satisfy the relational expression: 2.5 < |f7 / f S1 | < 3.2; The focal length of the eighth lens G8 is f8, and f8 and f S1 satisfy the relational expression: 1.6 < |f8 / f S1 | < 2.

4.

3. The optical system of a long working distance 10x large NA telecentric microscope lens according to claim 2, characterized in that, The rear group S2 includes a ninth lens G9 with negative refractive power, a tenth lens G10 with negative refractive power, and an eleventh lens G11 with positive refractive power. Among them, the tenth lens G10 and the eleventh lens G11 form a third cemented lens U3. The focal length of the ninth lens G9 is f9, and the f9 and the f S2 satisfy the relational expression: 1 < |f9 / f S2 | < 1.6; The focal length of the third cemented lens U3 is f U3 , f U3 and f S2 satisfy the relation: 4.9 < |f U3 / f S2 | < 5.7 4. The optical system of a long working distance 10x large NA telecentric microscope lens according to claim 3, characterized in that, 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, the ninth lens G9, the tenth lens G10, and the eleventh lens G11 are all spherical lenses, and the optical axes of all the spherical lenses are on the predetermined optical axis.

5. The optical system of a long working distance 10x large NA telecentric microscope lens according to claim 4, characterized in that, The first lens G1 and the third lens G3 are both meniscus lenses, the second lens G2, the fourth lens G4, the sixth lens G6, the seventh lens G7, and the eleventh lens G11 are all biconvex lenses, the fifth lens G5 and the tenth lens G10 are both biconcave lenses, and the ninth lens G9 is a meniscus lens or a plano-concave lens.

6. The optical system of a long working distance 10x large NA telecentric microscope lens according to claim 3, characterized in that, The materials of the second lens G2, the fourth lens G4, and the sixth lens G6 are all low-dispersion crown glasses, and the material of the eighth lens G8 is a high-dispersion flint glass.

7. The optical system of a long working distance 10x large NA telecentric microscope lens according to claim 1, characterized in that, The maximum outer diameters of all the lenses in the front group S1 are set to Φ36mm, and the maximum outer diameters of all the lenses in the rear group S2 are set to Φ8mm.

8. An optical system of a long working distance 10x large NA telecentric microscope lens according to claim 1, characterized in that, A beam-splitting prism P is also arranged between the front group S1 and the diaphragm T. The beam-splitting prism P is a semi-transmissive and semi-reflective prism, and the rear group S2 is arranged on the refraction path of the beam-splitting prism P. A coaxial illumination light source or an imaging component is also arranged on the reflection path of the beam-splitting prism P.

9. The optical system of a long working distance 10x large NA telecentric microscope lens according to claim 4, characterized in that, The aperture of the diaphragm T is a circular hole, and the center of the circular hole is on the predetermined optical axis.

10. A long working distance 10x large NA telecentric microscope lens, characterized in that, It includes an optical system of a long working distance 10 times large NA telecentric microscope lens as described in any one of claims 1-9.

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