Visible light and short wave infrared confocal telecentric lens and optical system thereof

Abstract

The invention relates to the technical field of optical lenses, and discloses a visible light and short wave infrared confocal telecentric lens and an optical system thereof. The optical system comprises a front group S1, a diaphragm T and a rear group S2 which are sequentially arranged from an object side to an image side, both the front group S1 and the rear group S2 have positive focal power; the combined focal length of the front group S1 is fS1, the combined focal length of the rear group S2 is fS2, and fS1 and fS2 meet the relational expression of 1lt; fS1 / fS2lt; 3. According to the optical system of the visible light and short wave infrared confocal telecentric lens, through reasonable lens combination design, material selection and focal length matching, the focus displacement within the wavelength range of 436-1000 nm is smaller than 40 micrometers, and the application requirement of visible light and short wave infrared confocal can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of optical lenses, and in particular to a visible light and short-wave infrared confocal telecentric lens and an optical system thereof. Background Art

[0002] In precision optical measurement systems, the use of ordinary industrial lenses will cause problems such as different magnifications, parallax, and large distortion due to changes in object distance, making it difficult to meet high detection requirements. Telecentric lenses can reduce or even eliminate the above problems. Within a certain object distance range, the image magnification will not change with changes in object distance. Its principle advantage makes it very suitable for the field of precision measurement and detection.

[0003] The telecentric lenses currently on the market are mainly visible light band telecentric lenses. Telecentric lenses are widely used in 3C electronics, new energy, packaging and printing, smart logistics, automobile manufacturing, medicine and other fields. Some inspection fields, such as wafer and MEMS (Micro-Electro-Mechanical System) inspection, circuit board inspection, etc., will use visible light and short-wave infrared at the same time. If the visible light telecentric lens is used in the short-wave infrared band, in addition to the imaging effect will be reduced, because the visible light band and the short-wave infrared band are not confocal, it will lead to the inability to clearly image at the same position at the same time. There is currently a lack of telecentric lenses that can be confocal with visible light and short-wave infrared on the market.

[0004] Therefore, for those skilled in the art, it is urgent to improve the existing telecentric industrial lens so that it can meet the application requirements of visible light and short-wave infrared confocal.

[0005] 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

[0006] The object of the present invention is to provide a visible light and short-wave infrared confocal telecentric lens and an optical system thereof, so as to solve or at least partially solve the technical problems existing in the prior art.

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

[0008] In a first aspect, the present invention provides an optical system of a visible light and short-wave infrared confocal telecentric lens, comprising a front group S1, a stop T and a rear group S2 arranged in sequence from the object side to the image side; the front group S1 and the rear group S2 both have positive focal power;

[0009] The front group S1 includes a first lens G1 with positive refractive power, a second lens G2 with negative refractive power, a third lens G3 with positive refractive power, a fourth lens G4 with positive refractive power, and a fifth lens G5 with negative refractive power, which are arranged in sequence from the object side to the image side.

[0010] The rear group S2 includes a sixth lens G6 with negative refractive power, a seventh lens G7 with positive refractive power, an eighth lens G8 with positive refractive power, and a ninth lens G9 with positive refractive power, which are arranged in sequence from the object side to the image side.

[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 With f S2 Satisfies the relationship: 1<|f S1 / f S2 |<3.

[0012] Optionally, the second lens G2 and the third lens G3 form a first cemented lens group U1, and the fourth lens G4 and the fifth lens G5 form a second cemented lens group U2;

[0013] The focal length of the first lens G1 is f G1 , f G1 With f S1 Satisfies the relationship: 1.5<|f G1 / f S1 |<2.5;

[0014] The focal length of the first cemented lens group U1 is f U1 , f U1 With f S1 Satisfies the relationship: 11.5<|f U1 / f S1 |<21.5;

[0015] The focal length of the second cemented lens group U2 is f U2 , f U2 With f S1 Satisfies the relationship: 2.5<|f U2 / f S1 |<3.5.

[0016] Optionally, the sixth lens G6 and the seventh lens G7 form a third cemented lens group U3, and the third cemented lens group U3 is an achromatic lens group;

[0017] The focal length of the third cemented lens group U3 is f U3 , f U3 With f S2 Satisfies the relationship: 0.65<|f U3 / f S2|<1.35;

[0018] The focal length of the eighth lens G8 is f G8 , f G8 With f S2 Satisfies the relationship: 1.3<|f G8 / f S2 |<1.9;

[0019] The focal length of the ninth lens G9 is f G9 , f G9 With f S2 Satisfies the relationship: 1.2<|f G9 / f S2 |<1.8.

[0020] Optionally, the first lens G1 is a plano-convex lens, the second lens G2 is a meniscus lens, the third lens G3 and the fourth lens G4 are both biconvex lenses, and the fifth lens G5 is a biconcave lens;

[0021] The sixth lens G6 is a biconcave lens, the seventh lens G7 and the ninth lens G9 are both biconvex lenses, and the eighth lens G8 is a meniscus lens.

[0022] Optionally, the first lens G1 is made of high-dispersion glass material, and the third lens G3, the fourth lens G4, the seventh lens G7 and the eighth lens G8 are all made of low-dispersion glass material.

[0023] 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 and the ninth lens G9 are all on a predetermined optical axis;

[0024] The aperture of the diaphragm T is a circular hole, and the center of the circular hole is on the predetermined optical axis.

[0025] Optionally, the optical system uses a wavelength range of 400nm to 1000nm.

[0026] Optionally, a beam splitter prism P is further disposed between the first lens G1 and the second lens G2;

[0027] The beam splitter prism P is a semi-transparent and semi-reflective prism; 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 arranged on the refraction path of the beam splitter prism P; a coaxial illumination light source or an imaging system is also arranged on the reflection light path of the beam splitter prism P.

[0028] In a second aspect, the present invention provides a visible light and short-wave infrared confocal telecentric lens, including an optical system of the visible light and short-wave infrared confocal telecentric lens as described above.

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

[0030] The invention provides a visible light and short-wave infrared confocal telecentric lens, which, through reasonable lens combination design, material selection and focal length matching, has a focus displacement of less than 40 microns within a wavelength range of 436nm to 1000nm, and can meet the application requirements of visible light and short-wave infrared confocal.

[0031] 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

[0032] 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.

[0033] Figure 1 It is a structural schematic diagram of an optical system of a visible light and short-wave infrared confocal telecentric lens provided by an embodiment of the present invention.

[0034] Figure 2 It is an MTF diagram of the white light band (436nm-700nm) of an optical system of a visible light and short-wave infrared confocal telecentric lens provided by an embodiment of the present invention.

[0035] Figure 3 The MTF diagram of the short-wave infrared (700nm-1000nm) of the optical system of the visible light and short-wave infrared confocal telecentric lens provided by the embodiment of the present invention is

[0036] Figure 4 It is a polychromatic light focus displacement curve diagram of an optical system of a visible light and short-wave infrared confocal 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, the spatially related expressions used, such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "perpendicular", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. It is only for the convenience of describing the specific embodiments of the present application or facilitating the understanding of the reader, 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 construed as a limitation to the embodiments of the present application.

[0045] Unless otherwise clearly specified or limited, in the description of the embodiments of the present application, the terms "mounted", "connected", "coupled", "fixed", "arranged", etc. shall be understood in a broad sense. For example, the "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 directly connected, or indirectly connected through an intermediate medium; it can be the communication inside two elements or the interaction relationship between two elements. For those skilled in the art to which the present application pertains, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0046] Embodiment 1:

[0047] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of an optical system of a visible light and short-wave infrared confocal telecentric lens provided by an embodiment of the present invention.

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

[0049] A front group S1, a diaphragm T, and a rear group S2 arranged in sequence from the object side to the image side; both the front group S1 and the rear group S2 have positive optical powers;

[0050] The front group S1 includes a first lens G1 with positive optical power, a second lens G2 with negative optical power, a third lens G3 with positive optical power, a fourth lens G4 with positive optical power, and a fifth lens G5 with negative optical power arranged in sequence from the object side to the image side;

[0051] The rear group S2 includes a sixth lens G6 with negative optical power, a seventh lens G7 with positive optical power, an eighth lens G8 with positive optical power, and a ninth lens G9 with positive optical power arranged in sequence from the object side to the image side;

[0052] The combined focal length of the front group S1 is f S1 , and the combined focal length of the rear group S2 is fS2 , f S1 With f S2 Satisfies the relationship: 1<|f S1 / f S2 |<3.

[0053] Furthermore, the second lens G2 and the third lens G3 form a first cemented lens group U1, and the fourth lens G4 and the fifth lens G5 form a second cemented lens group U2; the first lens G1 is made of high dispersion glass material;

[0054] The focal length of the first lens G1 is f G1 , f G1 With f S1 Satisfies the relationship: 1.5<|f G1 / f S1 |<2.5;

[0055] The focal length of the first cemented lens group U1 is f U1 , f U1 With f S1 Satisfies the relationship: 11.5<|f U1 / f S1 |<21.5;

[0056] The focal length of the second cemented lens group U2 is f U2 , f U2 With f S1 Satisfies the relationship: 2.5<|f U2 / f S1 |<3.5.

[0057] To achieve visible light and short-wave infrared confocality, wide spectrum chromatic aberration balance is required. In this embodiment, the first lens G1 is made of a material with high dispersion to induce high-level chromatic aberration. At the same time, the first lens G1 and the first cemented lens group U1 are separated by a certain distance. The first cemented lens group U1 has a smaller optical power, which is conducive to correcting wide spectrum chromatic aberration and also provides a good foundation for correcting the aberration of the subsequent lenses.

[0058] In this embodiment, the second cemented lens group U2 has a larger central thickness, which is beneficial for correcting field curvature in addition to correcting chromatic aberration.

[0059] Furthermore, the sixth lens G6 and the seventh lens G7 form a third cemented lens group U3, and the third cemented lens group U3 is an achromatic lens group; the third cemented lens group U3 can balance the chromatic aberration of the rear group S2, and the cemented surface thereof can correct astigmatism;

[0060] The focal length of the third cemented lens group U3 is f U3 , f U3 With f S2 Satisfies the relationship: 0.65<|fU3 / f S2 |<1.35;

[0061] The focal length of the eighth lens G8 is f G8 , f G8 With f S2 Satisfies the relationship: 1.3<|f G8 / f S2 |<1.9;

[0062] The focal length of the ninth lens G9 is f G9 , f G9 With f S2 Satisfies the relationship: 1.2<|f G9 / f S2 |<1.8.

[0063] Specifically, in this embodiment, the first lens G1 is a plano-convex lens, the second lens G2 is a meniscus lens, the third lens G3 and the fourth lens G4 are both biconvex lenses, and the fifth lens G5 is a biconcave lens;

[0064] The sixth lens G6 is a biconcave lens, the seventh lens G7 and the ninth lens G9 are both biconvex lenses, and the eighth lens G8 is a meniscus lens.

[0065] like Figure 1 As shown, the eighth lens G8 is a meniscus structure bent toward the aperture, which can better balance the spherical aberration and coma; the ninth lens G9 and the eighth lens G8 have similar focal lengths, which can better share the deflection refraction effect and reduce off-axis aberrations; the double convex structure is beneficial to the correction of distortion and the reduction of the incident angle of the main light on the image plane.

[0066] In this embodiment, the third lens G3, the fourth lens G4, the seventh lens G7 and the eighth lens G8 are made of low-dispersion glass materials, which also provides favorable conditions for balancing chromatic aberration.

[0067] 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 and the ninth lens G9 are all on a predetermined optical axis;

[0068] The aperture of the diaphragm T is a circular hole, and the center of the circular hole is on the predetermined optical axis.

[0069] In this embodiment, the optical system uses a wavelength range of 400 nm to 1000 nm.

[0070] It is understandable that the aperture value of the aperture T needs to be adjusted accordingly according to the specific application scenario.

[0071] In addition, a beam splitter prism P may be disposed between the first lens G1 and the second lens G2;

[0072] like Figure 1 As shown, the beam splitter prism P is a semi-transparent and semi-reflective prism; 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 arranged on the refraction path of the beam splitter prism P; a coaxial illumination light source or an imaging system is also arranged on the reflection light path of the beam splitter prism P.

[0073] In this embodiment, the beam splitter prism P can be used to introduce the illumination component to form coaxial illumination, and can also be used to introduce other imaging components;

[0074] It should be noted that, in general, the beam splitter prism of a telecentric lens is arranged in front of the aperture, and the coaxial light will be reflected by the lens in front of the aperture to form stray light, forming an irremovable bright spot on the image plane, affecting the brightness uniformity; while in the embodiment of the present invention, the beam splitter prism P is placed in front, which can effectively reduce the stray light reflected by the lens on the one hand, and increase the size of the beam splitter prism P on the other hand, and introduce a light source with a larger light-emitting area, thereby achieving a more uniform lighting effect.

[0075] In order to verify whether the above optical system meets the design purpose, the following is a specific test example given according to the above settings of this embodiment:

[0076] In this test example, the lens data of the optical system are shown in Table 1 below:

[0077] Table 1

[0078]

[0079]

[0080] It should be noted that in Table 1, the “front surface” corresponds to Figure 1 The 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".

[0081] In this test example, the telecentric lens optical system has a working distance of 74mm, a magnification of 0.5x, and a maximum aperture of F4.8. The combined focal length of the front group S1 is f S1 =36.6mm; the combined focal length of the rear group S2 is f S2 =18.7mm; the focal length of the first lens G1 is f G1 =74.8mm; focal length f of the first cemented lens group U1U1 =598mm; the focal length of the second cemented lens group U2 is f U2 =112.7mm; focal length f of the third cemented lens group U3 U3 =-18.4mm; the focal length of the eighth lens G8 is f G8 =29.6mm; the focal length of the ninth lens G9 is f G9 =27.8mm;

[0082] Substituting the above values ​​into each relational expression, we obtain:

[0083] |f S1 / f S2 |=1.957,|f G1 / f S1 |=2.044,|f U1 / f S1 |=16.339,|f U2 / f S1 |=3.079,|f U3 / f S2 |=0.984,|f G8 / f S2 |=1.583,|f G9 / f S2 |=1.487.

[0084] Therefore, the relevant relationship of this embodiment is satisfied, namely:

[0085] 1<|f S1 / f S2 |<3,1.5<|f G1 / f S1 |<2.5, 11.5<|f U1 / f S1 |<21.5, 2.5<|f U2 / f S1 |<3.5, 0.65<|f U3 / f S2 |<1.35, 1.3<|f G8 / f S2 |<1.9,1.2<|f G9 / f S2 |<1.8.

[0086] In this embodiment, the wavelength range applicable to the optical system is 400nm to 1000nm.

[0087] Attached Figure 2 and attached Figure 3 They are the MTF of white light band and short-wave infrared band under confocal conditions, and Figure 4The focal displacement of the optical system in the entire wavelength range is less than 40 microns, which meets the requirements for confocal imaging of visible light and short-wave infrared.

[0088] Please refer to Figure 2 , Figure 3 and Figure 4 , Figure 2 It is a MTF (Modulation Transfer Function) diagram of a white light band (436nm-700nm) of an optical system of a visible light and short-wave infrared confocal telecentric lens provided by an embodiment of the present invention, Figure 3 is a short-wave infrared (700nm-1000nm) MTF diagram of an optical system of a visible light and short-wave infrared confocal telecentric lens provided by an embodiment of the present invention, Figure 4 It is a polychromatic light focus displacement curve diagram of an optical system of a visible light and short-wave infrared confocal telecentric lens provided by an embodiment of the present invention;

[0089] like Figure 2 and Figure 3 They are the MTF of white light band and short-wave infrared band under confocal conditions; Figure 4 The focal displacement of the optical system in the entire wavelength range is less than 40 microns, which meets the requirements for confocal imaging of visible light and short-wave infrared.

[0090] The optical system of a visible light and short-wave infrared confocal telecentric lens provided in this embodiment has a focus displacement of less than 40 microns in the wavelength range of 436nm to 1000nm through reasonable lens combination design, material selection and focal length matching, which can meet the application requirements of visible light and short-wave infrared confocal.

[0091] Embodiment 2:

[0092] This embodiment provides a visible light and short-wave infrared confocal telecentric lens, including an optical system of a visible light and short-wave infrared confocal telecentric lens as described in the first embodiment.

[0093] Since the optical system has been described in detail in the above embodiments, it will not be described in detail in this embodiment.

[0094] In summary, the embodiments of the present invention provide a visible light and short-wave infrared confocal telecentric lens to address the deficiencies in the prior art, which can meet the application requirements of visible light and short-wave infrared confocal telecentric lens.

[0095] 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 visible light and short-wave infrared confocal telecentric lenses, characterized in that: It includes a front group S1, a stop T and a rear group S2 which are arranged in sequence from the object side to the image side; the front group S1 and the rear group S2 both have positive refractive power; The front group S1 includes a first lens G1 with positive refractive power, a second lens G2 with negative refractive power, a third lens G3 with positive refractive power, a fourth lens G4 with positive refractive power, and a fifth lens G5 with negative refractive power, which are arranged in sequence from the object side to the image side. The rear group S2 includes a sixth lens G6 with negative refractive power, a seventh lens G7 with positive refractive power, an eighth lens G8 with positive refractive power, and a ninth lens G9 with positive refractive power, which are arranged in sequence from the object side to the image side. 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 With f S2 Satisfies the relationship: 1<|f S1 / f S2 |<3.

2. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 1, characterized in that: The second lens G2 and the third lens G3 form a first cemented lens group U1, and the fourth lens G4 and the fifth lens G5 form a second cemented lens group U2; The focal length of the first lens G1 is f G1 , f G1 With f S1 Satisfies the relationship: 1.5<|f G1 / f S1 |<2.5; The focal length of the first cemented lens group U1 is f U1 , f U1 With f S1 Satisfies the relationship: 11.5<|f U1 / f S1 |<21.5; The focal length of the second cemented lens group U2 is f U2 , f U2 With f S1 Satisfies the relationship: 2.5<|f U2 / f S1 |<3.

5.

3. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 2, characterized in that: The sixth lens G6 and the seventh lens G7 form a third cemented lens group U3, and the third cemented lens group U3 is an achromatic lens group; The focal length of the third cemented lens group U3 is f U3 , f U3 With f S2 Satisfies the relationship: 0.65<|f U3 / f S2 |<1.35; The focal length of the eighth lens G8 is f G8 , f G8 With f S2 Satisfies the relationship: 1.3<|f G8 / f S2 |<1.9; The focal length of the ninth lens G9 is f G9 , f G9 With f S2 Satisfies the relationship: 1.2<|f G9 / f S2 |<1.

8.

4. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 3, characterized in that: The first lens G1 is a plano-convex lens, the second lens G2 is a meniscus lens, the third lens G3 and the fourth lens G4 are both biconvex lenses, and the fifth lens G5 is a biconcave lens; The sixth lens G6 is a biconcave lens, the seventh lens G7 and the ninth lens G9 are both biconvex lenses, and the eighth lens G8 is a meniscus lens.

5. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 4, characterized in that: The first lens G1 is made of high-dispersion glass material, and the third lens G3, the fourth lens G4, the seventh lens G7 and the eighth lens G8 are all made of low-dispersion glass material.

6. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 4, 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 and the ninth lens G9 are all on a predetermined optical axis; The aperture of the diaphragm T is a circular hole, and the center of the circular hole is on the predetermined optical axis.

7. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 1, characterized in that: The optical system has a wavelength range of 400 nm to 1000 nm.

8. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 1, characterized in that: A beam splitter prism P is also provided between the first lens G1 and the second lens G2; The beam splitter prism P is a semi-transparent and semi-reflective prism; 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 arranged on the refraction path of the beam splitter prism P; a coaxial illumination light source or an imaging system is also arranged on the reflection light path of the beam splitter prism P.

9. A visible light and short-wave infrared confocal telecentric lens, characterized in that: An optical system comprising a visible light and short-wave infrared confocal telecentric lens as described in any one of claims 1 to 8.

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