High-magnification large-target-surface telecentric lens and optical system thereof

Abstract

The invention relates to the technical field of optical lenses, and discloses a high-magnification large-target-surface telecentric lens and an optical system thereof. The optical system is sequentially provided with a first lens G1 with positive focal power, a second lens G2 with positive focal power, a third lens G3 with negative focal power, a fourth lens G4 with positive focal power, a fifth lens G5 with positive focal power, a sixth lens G6 with negative focal power, a seventh lens G7 with positive focal power, a beam splitter prism BS and a diaphragm T from an object side to an image side. An eighth lens G8 with negative focal power; a ninth lens G9 with positive focal power; and a tenth lens G10 with positive focal power. The beam splitter prism BS is a semi-transparent and semi-reflective prism; and the diaphragm T is arranged at the focal point of the front group to form a telecentric framework. The optical system of the high-magnification large-target-surface telecentric lens provided by the invention has a relatively high magnification and a relatively large numerical aperture, and can realize high-precision detection.

Description

Technical Field

[0001] The invention relates to the technical field of optical lenses, and in particular to a high-magnification large-target-surface telecentric lens and an optical system thereof. Background Art

[0002] In the machine vision precision optical measurement system, the use of ordinary industrial lenses will cause the following problems: changes in object distance will cause different magnifications, parallax, large distortion, etc., while telecentric lenses can reduce or even eliminate the above problems. It can ensure that the image magnification does not change with the change of object distance within a certain object distance range. Its principle advantage makes it very suitable for precision measurement and detection.

[0003] In the high-precision detection fields such as semiconductors, mini LEDs (Light Emitting Diodes), FPDs (Flat Panel Displays), and pan-semiconductors, high-magnification telecentric lenses that support high-pixel and large-target cameras are required. The target surfaces of existing high-magnification telecentric lenses are almost all below 1.1 inches, which does not meet the detection requirements. On the other hand, the existing high-magnification telecentric lens coaxial illumination simply places a general point light source at the aperture. Due to the small light-emitting area of ​​the point light source, the numerical aperture of the high-magnification telecentric lens is generally large, resulting in a mismatch between the point light source and the entrance pupil of the telecentric lens, and a good coaxial incident illumination cannot be formed, which not only reduces the imaging contrast, but also forms a hotspot effect and stray light.

[0004] The above information is presented as background information only to assist with understanding the present disclosure and no determination or admission is made as to whether any of the above may be used as prior art with respect to the present disclosure. Summary of the invention

[0005] The object of the present invention is to provide a high-magnification large-target-surface telecentric lens and an optical system thereof, so as to solve or at least partially solve the technical problems existing in the prior art.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides an optical system of a high-magnification large-target-surface telecentric lens, comprising a first lens G1 with positive focal power, a second lens G2 with positive focal power, a third lens G3 with negative focal power, a fourth lens G4 with positive focal power, a fifth lens G5 with positive focal power, a sixth lens G6 with negative focal power, a seventh lens G7 with positive focal power, a beam splitter BS, an aperture T, an eighth lens G8 with negative focal power, a ninth lens G9 with positive focal power, and a tenth lens G10 with positive focal power, which are sequentially arranged from the object side to the image side;

[0008] The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, the fifth lens G5, the sixth lens G6 and the seventh lens G7 form a front group (100); the beam splitter BS is a semi-transparent and semi-reflective prism; the aperture T is arranged at the focus of the front group (100) to form a telecentric structure;

[0009] The working distance of the optical system is WD, the numerical aperture of the optical system is NA, and WD and NA satisfy the relationship: NA×WD<15.

[0010] Optionally, the focal length of the front group is f 100 , f 100 Satisfies the relationship with WD: 0.48<|f 100 / WD|<0.88;

[0011] The ninth lens G9 and the tenth lens G10 form a rear group, and the focal length of the rear group is f 200 The focal length of the eighth lens G8 is f8, and f8 is equal to f 200 Satisfies the relationship: 0.2<|f8 / f 200 |<0.5.

[0012] Optionally, the second lens G2, the third lens G3 and the fourth lens G4 form a triplet lens group U1, and the fifth lens G5 and the sixth lens G6 form a doublet lens group U2;

[0013] The focal length of the first lens G1 is f1, and f1 and f 100 Satisfies the relationship: 1.3<|f1 / f 100 |<2.3;

[0014] The focal length of the triplet lens group U1 is f U1 , f U1 With f 100 Satisfies the relationship: |f 100 / f U1 |<0.15;

[0015] The focal length of the seventh lens G7 is f7. 100 Satisfies the relationship: 1.3<|f7 / f 100 |<2;

[0016] The focal length of the doublet lens group U2 is f U2 , f U2 With f 100 Satisfies the relationship: |f 100 / f U2 |<0.25.

[0017] Optionally, the first lens G1, the second lens G2, the fourth lens G4, the fifth lens G5, and the seventh lens G7 are all biconvex lenses; the third lens G3 and the eighth lens G8 are all biconcave lenses; the sixth lens G6, the ninth lens G9, and the tenth lens G10 are all meniscus lenses.

[0018] Optionally, in the triplet lens group U1, the refractive index Nd2 of the second lens G2 and the Abbe number Vd2 of the second lens G2 satisfy the relationship: 1.42 <Nd2<1.65,60<Vd2<95;

[0019] The refractive index Nd4 of the fourth lens G4 and the Abbe number Vd4 of the fourth lens G4 satisfy the relationship: Fourth lens: 1.42 <Nd4<1.65,60<Vd4<95。

[0020] Optionally, the optical system further comprises a coaxial illumination assembly;

[0021] The coaxial lighting assembly is arranged on the reflected light path of the beam splitter prism BS, and includes a second condenser lens C2, a first condenser lens C1 and a reflector M arranged in sequence from the light entrance surface A to the light exit surface B of the point light source;

[0022] The first condenser lens C1 and the second condenser lens C2 are used to amplify and shape the incident light beam of the point light source so that the angle and spot size of the light beam at the light exit surface B match the aperture of the aperture T; the reflector M is used to deflect the shaped light beam.

[0023] Optionally, the first condenser lens C1 and the second condenser lens C2 form a condenser lens group, the condenser lens group has positive focal power, and its combined focal length is f 310 , f 310 Satisfy the relationship: 8 <f 310 <18.

[0024] Optionally, the optical axes of 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 and the tenth lens G10 all coincide with a predetermined optical axis;

[0025] The optical axis of the first condensing lens C1 coincides with the optical axis of the second condensing lens C2, and the optical axis of the first condensing lens C1 is parallel to the predetermined optical axis.

[0026] Optionally, the aperture of the diaphragm T is a circular hole, and the center of the circular hole is on the predetermined optical axis.

[0027] In a second aspect, the present invention provides a high-magnification large-target-surface telecentric lens, including an optical system of the high-magnification large-target-surface telecentric lens as described above.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The optical system of a high-magnification large-target telecentric lens provided by the present invention has a high magnification and a large numerical aperture, and can achieve high-precision detection; the maximum imaging surface reaches Φ44mm, and can be used with cameras such as 6500W pixels, 38mm diagonal area array cameras or 8k5μm line scan cameras to meet the needs of high-precision detection fields such as semiconductors, mini LEDs, FPDs, and pan-semiconductors.

[0030] The present invention has other features and advantages, which will be apparent from or will be described in detail in the accompanying drawings and the following detailed description incorporated herein, which together serve to explain the specific principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 It is a schematic structural diagram of an optical system of a high-magnification large-target-surface telecentric lens provided in an embodiment of the present invention.

[0033] Figure 2 yes Figure 1 Schematic diagram of the light path.

[0034] Figure 3 It is a structural schematic diagram of a coaxial illumination assembly of an optical system of a high-magnification large-target-surface telecentric lens provided in an embodiment of the present invention.

[0035] Figure 4 This is an MTF diagram of an optical system of a high-magnification large-target telecentric lens provided by an embodiment of the present invention.

[0036] Figure 5 The optical distortion curve diagram of the optical system of a high-magnification large-target telecentric lens provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to explain in detail the possible application scenarios, technical principles, specific schemes that can be implemented, and the purposes and effects that can be achieved, the following is a detailed description of the specific embodiments listed in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

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

[0039] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.

[0040] In the description of this application, the term "and / or" is an expression used to describe the logical relationship between objects, indicating that three relationships may exist, for example, A and / or B, which means: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in this article generally indicates that the objects before and after are in an "or" logical relationship.

[0041] In the present application, terms such as “first” and “second” are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship of quantity, priority or sequence between these entities or operations.

[0042] Without further limitations, in this application, the words "include", "comprises", "has" or other similar expressions used in the sentences are intended to cover non-exclusive inclusion. These expressions do not exclude the presence of additional elements in the process, method or product including the elements, so that the process, method or product including a series of elements may include not only those limited elements, but also other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0043] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than", "less than", "exceed" and the like are understood to exclude the number itself; expressions such as "above", "below", "within" and the like are understood to include the number itself. In addition, in the description of the embodiments of this application, "multiple" means more than two (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups", "multiple times", etc., unless otherwise clearly and specifically limited.

[0044] In the description of the embodiments of the present application, space-related expressions used, such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or position relationship based on the orientation or position relationship shown in the specific embodiments or drawings, and are only for the convenience of describing the specific embodiments of the present application or facilitating the reader's understanding, and do not indicate or imply that the referred device or component must have a specific position, a specific orientation, or be constructed or operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0045] Unless otherwise expressly specified or limited, in the description of the embodiments of the present application, the terms such as "install", "connect", "connect", "fix", "set", etc. used should be understood in a broad sense. For example, the "connection" can be a fixed connection, a detachable connection, or an integrated setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For technicians in the technical field to which the present application belongs, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0046] Embodiment 1:

[0047] See also Figure 1 and Figure 2 , Figure 1 is a schematic structural diagram of an optical system of a high-magnification large-target-surface telecentric lens provided by an embodiment of the present invention, Figure 2 yes Figure 1 Schematic diagram of the optical path;

[0048] like Figure 1 As shown, the optical system includes:

[0049] A first lens G1 with positive power, a second lens G2 with positive power, a third lens G3 with negative power, a fourth lens G4 with positive power, a fifth lens G5 with positive power, a sixth lens G6 with negative power, a seventh lens G7 with positive power, a beam splitter BS, a stop T, an eighth lens G8 with negative power, a ninth lens G9 with positive power, and a tenth lens G10 with positive power are arranged in sequence from the object side to the image side;

[0050] The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, the fifth lens G5, the sixth lens G6 and the seventh lens G7 form a front group 100; the beam splitter BS is a semi-transparent and semi-reflective prism; the aperture T is set at the focus of the front group 100 to form a telecentric structure;

[0051] The working distance of the optical system is WD, the numerical aperture of the optical system is NA, and WD and NA satisfy the relationship: NA×WD<15.

[0052] Furthermore, the focal length of the front group 100 is f 100 , f 100 Satisfies the relationship with WD: 0.48<|f 100 / WD|<0.88;

[0053] The ninth lens G9 and the tenth lens G10 form a rear group 200, and the focal length of the rear group 200 is f 200 The focal length of the eighth lens G8 is f8, and f8 is equal to f 200 Satisfies the relationship: 0.2<|f8 / f 200 |<0.5.

[0054] Specifically, the second lens G2, the third lens G3 and the fourth lens G4 form a triplet lens group U1, and the fifth lens G5 and the sixth lens G6 form a doublet lens group U2;

[0055] The focal length of the first lens G1 is f1, and f1 and f 100 Satisfies the relationship: 1.3<|f1 / f 100 |<2.3; the focal length of the triplet lens group U1 is f U1 , f U1 With f 100 Satisfies the relationship: |f 100 / f U1 |<0.15;

[0056] The focal length of the seventh lens G7 is f7. 100 Satisfies the relationship: 1.3<|f7 / f 100 |<2;

[0057] The focal length of the doublet lens group U2 is f U2 , f U2 With f 100 Satisfies the relationship: |f 100 / f U2 |<0.25.

[0058] like Figure 2 As shown, the first lens G1 has a larger deflection and refraction power, forming a light beam close to a parallel optical axis to enter the rear lens. In this embodiment, the first lens G1 is made of a material with a higher refractive index, which is beneficial to reduce spherical aberration.

[0059] The triplet lens group U1 and the doublet lens group U2 have smaller optical focal lengths, and the light rays pass through U1 and U2 in nearly parallel manner. The cemented surfaces thereof have negative optical focal lengths, which can correct the spherical aberration and higher-order aberrations of the optical system.

[0060] More specifically, the first lens G1, the second lens G2, the fourth lens G4, the fifth lens G5, and the seventh lens G7 are all biconvex lenses; the third lens G3 and the eighth lens G8 are all biconcave lenses; the sixth lens G6, the ninth lens G9, and the tenth lens G10 are all meniscus lenses.

[0061] Both the front group 100 and the rear group 200 have positive optical power, and combined with the seventh lens G7 with negative optical power, they can well correct the field curvature and spherical aberration of the system; the ninth lens G9 is a meniscus structure bent toward the aperture T, and the tenth lens G10 is a meniscus structure bent toward the image plane. This structural combination can correct the coma, astigmatism and distortion of the system.

[0062] Furthermore, in the triplet lens group U1, the refractive index Nd2 of the second lens G2 and the Abbe number Vd2 of the second lens G2 satisfy the relationship: 1.42 <Nd2<1.65,60<Vd2<95;

[0063] The refractive index Nd4 of the fourth lens G4 and the Abbe number Vd4 of the fourth lens G4 satisfy the relationship: Fourth lens: 1.42 <Nd4<1.65,60<Vd4<95。

[0064] Using a lens combination that satisfies the above refractive index and dispersion relationship is more conducive to correcting system chromatic aberration.

[0065] Please combine Figure 2 and Figure 3 , Figure 3 for Figure 3 It is a structural schematic diagram of a coaxial illumination assembly of an optical system of a high-magnification large-target-surface telecentric lens provided by an embodiment of the present invention;

[0066] The optical system also includes a coaxial illumination assembly 300;

[0067] The coaxial lighting assembly 300 is arranged on the reflected light path of the beam splitter prism BS. Figure 3 As shown, the coaxial lighting assembly 300 includes a second condenser lens C2, a first condenser lens C1 and a reflector M which are arranged in sequence from the light entrance surface A to the light exit surface B of the point light source;

[0068] Among them, the first condensing lens C1 and the second condensing lens C2 are used to amplify and shape the incident light beam of the point light source, so that the angle and spot size of the light beam at the light exit surface B match the aperture of the diaphragm T, thereby forming a good coaxial incident illumination, reducing the hotspot effect and stray light, and improving the imaging contrast; the reflector M is used to turn the shaped light beam, which can reduce the structural size.

[0069] In the embodiment of the present application, the specification parameters of the first condensing lens C1 and the second condensing lens C2 are set to be the same, which can reduce the production cost.

[0070] Specifically, the first condensing lens C1 and the second condensing lens C2 form a condensing lens group 310, and the condensing lens group 310 has positive focal length, and its combined focal length is f 310 , f 310 Satisfy the relationship: 8 <f 310 <18.

[0071] In this embodiment, the optical axes of 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 and the tenth lens G10 all coincide with the predetermined optical axis;

[0072] The optical axis of the first condensing lens C1 coincides with the optical axis of the second condensing lens C2, and the optical axis of the first condensing lens C1 is parallel to the predetermined optical axis.

[0073] In this embodiment, the aperture of the aperture 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 aperture T needs to be adjusted accordingly according to the specific application scenario.

[0074] Furthermore, in order to evaluate whether the performance of the optical system meets the expected requirements, a specific application example is given below and experimental verification is performed;

[0075] In this application example, the relevant data of the optical system are shown in Table 1:

[0076] Table 1

[0077] surface Radius(mm) Thickness(mm) Refractive Index Abbe number G1 front surface 572.26 13.6 1.90 - G1 rear surface -109.14 11.8 G2 front surface 125.46 11.8 1.50 80 G2, G3 glued surface -115.91 3.2 1.75 - G3, G4 glued surface 63.80 8.2 1.50 80 G4 rear surface -2004.20 0.2 G5 front surface 326.0 9.6 1.65 - G5, G6 bonding surface -76.1 3.0 1.75 - G6 rear surface -305.98 0.2 G7 front surface 66.77 10.0 1.65 - G7 rear surface -669.67 3.0 Beam splitter BS ∞ 35.0 1.52 64.2 ∞ 3.0 Aperture T ∞ 31.1 G8 front surface -25.94 5.5 1.80 - G8 rear surface 94.70 40.6 G9 front surface -142.21 8.8 1.85 - G9 rear surface -65.29 4.5 G10 front surface 88.99 11.8 1.80 - G10 rear surface 269.16 84.6 Image plane ∞

[0078] It should be noted that in Table 1, the “front surface” corresponds to Figure 1The left side surface of the lens or lens group corresponds to the "back surface" Figure 1 The corresponding lens or lens group on the right side surface; or can be understood as: the object side is Figure 1 On the left, the image side (or image plane) is Figure 1 On the right side, the surface close to the object side is the "front surface", and the surface close to the image side is the "back surface".

[0079] In this application example, the combined focal length f of the front group 100 is 100 =57mm; the focal length of the first lens G1 is f1=102mm; the focal length of the triplet lens group U1 is f U1 =-577mm; the focal length of the doublet lens group U2 is f U2 =324mm; the focal length of the seventh lens G7 is f7=94mm; the focal length of the eighth lens G8 is f8=-25mm; the focal length of the ninth lens G9 is f9=134mm; the focal length of the tenth lens G10 is f 10 =160mm; the focal length of the lens group 200 is f 200 =72mm; the combined focal length of the condenser lens group 310 is f 310 =14.5mm.

[0080] In this application example, the optical path data of the coaxial lighting assembly 300 is shown in Table 2 below:

[0081] Table 2

[0082] surface Radius(mm) Thickness(mm) Refractive Index Light incident surface A ∞ 14 C1 front surface 57.50 3.0 1.50 C1 rear surface -16.20 3.8 C2 front surface 57.50 3.0 1.50 C2 rear surface -16.20 20 Reflector M ∞ 26 Light emitting surface B ∞

[0083] The optical parameters of the optical system are shown in Table 3 below:

[0084] Table 3

[0085] Working distance WD 83mm Numerical Aperture NA 0.16 Resolution 2.2 microns Magnification 3 times Target surface Φ44mm Telecentricity <0.1°

[0086] Substituting the above values ​​into each relational expression, we obtain:

[0087] NA×WD|=13.28,|f 100 / WD|=0.687,|f8 / f 200 |=0.347,|f1 / f 100 |=1.789,

[0088] |f 100 / f U1 |=0.099,|f7 / f 100 |=1.649,|f8 / f 200 |=0.347,|f 100 / f U2 |=0.176.

[0089] Therefore, the relevant relationship of this embodiment is satisfied, namely:

[0090] NA×WD<15, 0.48<|f 100 / WD|<0.88, 0.2<|f8 / f 200 |<0.5, 1.3<|f1 / f 100 |<2.3,

[0091] |f 100 / f U1 |<0.15, 1.3<|f7 / f 100 |<2, 0.2<|f8 / f 200 |<0.5,|f 100 / f U2 |<0.25.

[0092] Please continue to refer to Figure 4 and Figure 5 , Figure 4 is an MTF diagram of an optical system of a high-magnification large-target telecentric lens provided by an embodiment of the present invention, Figure 5 It is an optical distortion curve diagram of an optical system of a high-magnification large-target-surface telecentric lens provided by an embodiment of the present invention;

[0093] According to experimental verification, the distortion curve of the optical system is less than 0.1%.

[0094] In summary, this embodiment realizes an optical system of a high-magnification large-target telecentric lens, which has a high magnification and a large numerical aperture, and the maximum imaging surface reaches Φ44mm, which can achieve high-precision detection; and, the optical system effectively improves the problem of poor coaxial lighting effect of existing high-magnification telecentric lenses by combining a coaxial lighting solution.

[0095] Embodiment 2:

[0096] This embodiment provides a high-magnification large-target-surface telecentric lens, including an optical system of the high-magnification large-target-surface telecentric lens as described in the first embodiment.

[0097] Since the optical system has been described in detail in the first embodiment, it will not be described in detail in this embodiment.

[0098] The present embodiment provides a high-magnification large-target telecentric lens, with an imaging target surface of Φ44mm, which can be used with cameras such as a 6500W pixel, 38mm diagonal area array camera or an 8k5μm line scan camera. In addition, the coaxial lighting solution in its optical system can effectively improve the problem of poor lighting effect of existing high-magnification telecentric lenses.

[0099] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An optical system of a high-magnification large-target telecentric lens, characterized in that: The invention comprises, arranged in sequence from the object side to the image side, a first lens G1 with positive power, a second lens G2 with positive power, a third lens G3 with negative power, a fourth lens G4 with positive power, a fifth lens G5 with positive power, a sixth lens G6 with negative power, a seventh lens G7 with positive power, a beam splitter BS, a stop T, an eighth lens G8 with negative power, a ninth lens G9 with positive power, and a tenth lens G10 with positive power; The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, the fifth lens G5, the sixth lens G6 and the seventh lens G7 form a front group (100); the beam splitter BS is a semi-transparent and semi-reflective prism; the aperture T is arranged at the focus of the front group (100) to form a telecentric structure; The working distance of the optical system is WD, the numerical aperture of the optical system is NA, and WD and NA satisfy the relationship: NA×WD<15.

2. The optical system of a high-magnification large-target-surface telecentric lens according to claim 1, characterized in that: The focal length of the front group (100) is f 100 , f 100 Satisfies the relationship with WD: 0.48<|f 100 / WD|<0.88; The ninth lens G9 and the tenth lens G10 form a rear group (200), and the focal length of the rear group (200) is f 200 The focal length of the eighth lens G8 is f8, and f8 is equal to f 200 Satisfies the relationship: 0.2<|f8 / f 200 |<0.

5.

3. The optical system of a high-magnification large-target-surface telecentric lens according to claim 2, characterized in that: The second lens G2, the third lens G3 and the fourth lens G4 form a triplet lens group U1, and the fifth lens G5 and the sixth lens G6 form a doublet lens group U2; The focal length of the first lens G1 is f1, and f1 and f 100 Satisfies the relationship: 1.3<|f1 / f 100 |<2.3; The focal length of the triplet lens group U1 is f U1 , f U1 With f 100 Satisfies the relationship: |f 100 / f U1 |<0.15; The focal length of the seventh lens G7 is f7. 100 Satisfies the relationship: 1.3<|f7 / f 100 |<2; The focal length of the doublet lens group U2 is f U2 , f U2 With f 100 Satisfies the relationship: |f 100 / f U2 |<0.

25.

4. The optical system of a high-magnification large-target-surface telecentric lens according to claim 3, characterized in that: The first lens G1, the second lens G2, the fourth lens G4, the fifth lens G5 and the seventh lens G7 are all biconvex lenses; the third lens G3 and the eighth lens G8 are all biconcave lenses; the sixth lens G6, the ninth lens G9 and the tenth lens G10 are all meniscus lenses.

5. The optical system of a high-magnification large-target-surface telecentric lens according to claim 3, characterized in that: In the triplet lens group U1, the refractive index Nd2 of the second lens G2 and the Abbe number Vd2 of the second lens G2 satisfy the relationship: 1.42 <Nd2<1.65,60<Vd2<95; The refractive index Nd4 of the fourth lens G4 and the Abbe number Vd4 of the fourth lens G4 satisfy the relationship: Fourth lens: 1.42 <Nd4<1.65,60<Vd4<95。 6. The optical system of a high-magnification large-target-surface telecentric lens according to claim 3, characterized in that: Also included is a coaxial lighting assembly (300); The coaxial lighting assembly (300) is arranged on the reflected light path of the beam splitter prism BS, and comprises a second condenser lens C2, a first condenser lens C1 and a reflector M which are arranged in sequence from the light entrance surface A to the light exit surface B of the point light source; The first condenser lens C1 and the second condenser lens C2 are used to amplify and shape the incident light beam of the point light source so that the angle and spot size of the light beam at the light exit surface B match the aperture of the aperture T; the reflector M is used to deflect the shaped light beam.

7. The optical system of a high-magnification large-target-surface telecentric lens according to claim 6, characterized in that: The first condenser lens C1 and the second condenser lens C2 form a condenser lens group (310). The condenser lens group (310) has positive focal power and a combined focal length of f 310 , f 310 Satisfy the relationship: 8 <f 310 <18.

8. The optical system of a high-magnification large-target-surface telecentric lens according to claim 7, characterized in that: The optical axes of 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 and the tenth lens G10 all coincide with the predetermined optical axis; The optical axis of the first condensing lens C1 coincides with the optical axis of the second condensing lens C2, and the optical axis of the first condensing lens C1 is parallel to the predetermined optical axis.

9. The optical system of a high-magnification large-target-surface telecentric lens according to claim 8, 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 high-magnification large-target telecentric lens, characterized in that: An optical system comprising a high-magnification, large-target-surface telecentric lens as described in any one of claims 1 to 9.

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