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

Abstract

The application 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, an aperture stop T and a rear group S2 arranged in sequence from an object side to an image side; the front group S1 and the rear group S2 both have positive refractive powers; 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 and f S2 satisfy the relationship: 1 < |f S1 / f S2 | < 3. The optical system of the visible light and short-wave infrared confocal telecentric lens can meet the application requirements of visible light and short-wave infrared confocal applications by reasonable lens combination design, material selection and focal length matching, and the focal point displacement is less than 40 microns in the wavelength range of 436 nm to 1000 nm.

Description

TECHNICAL FIELD

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

[0002] In a precise optical measurement system, using a common industrial lens can cause problems such as different magnification, parallax, and large distortion due to changes in object distance, which is difficult to meet the high detection requirements. The telecentric lens can reduce or even eliminate the above problems. It can make the resulting image magnification not change with the change of object distance within a certain object distance range. Its principle advantage makes it very suitable for the field of precise measurement and detection.

[0003] The telecentric lens on the market at present is mainly visible light band telecentric lens. Telecentric lenses are widely used in 3C electronics, new energy, packaging and printing, intelligent logistics, automobile manufacturing, medicine and other fields. Some detection fields, such as wafer and MEMS (Micro-Electro-Mechanical System) detection, circuit board detection, 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, the imaging effect will be reduced, and since the visible light band and the short-wave infrared band are not confocal, it will cause that the clear image cannot be formed at the same position at the same time. There is a lack of telecentric lens that can confocal visible light and short-wave infrared on the market at present.

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

[0005] The above information is given as background information only to assist with an understanding of the present disclosure, and does not constitute a recognition that any of the above information forms part of the prior art with respect to the present disclosure. SUMMARY

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

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

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

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

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

[0011] 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: 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 and f S1 satisfy 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 and f S1 satisfy 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 and f S1 satisfy 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 and f S2 satisfy the relationship: 0.65 < |f U3 / f S2| <1.35;

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

[0019] The focal length of the ninth lens G9 is f G9 , f G9 and f S2 satisfy 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 double-convex lenses, and the fifth lens G5 is a double-concave lens;

[0021] The sixth lens G6 is a double-concave lens, the seventh lens G7 and the ninth lens G9 are both double-convex lenses, and the eighth lens G8 is a meniscus lens.

[0022] Optionally, the first lens G1 is made of high-dispersion glass, 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.

[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 wavelength range used by the optical system is 400-1000 nm.

[0026] Optionally, a light splitting prism P is further arranged between the first lens G1 and the second lens G2;

[0027] The light splitting prism P is a semi-transmissive 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 refractive path of the light splitting prism P; and a coaxial illumination light source or an imaging system is further arranged on the reflective light path of the light splitting prism P.

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

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

[0030] The application provides a visible light and short-wave infrared confocal telecentric lens.

[0031] The application has other characteristics and advantages, which will be apparent or will be described in detail in the accompanying drawings and subsequent specific embodiments incorporated herein, which are collectively used to explain the specific principles of the application. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the accompanying drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

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

[0034] Figure 2 is an MTF 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 the embodiment of the application.

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

[0036] Figure 4 is a multi-color light focal point displacement curve diagram of an optical system of a visible light and short-wave infrared confocal telecentric lens provided by the embodiment of the application. DETAILED DESCRIPTION

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the accompanying drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0038] The term "embodiment" is mentioned in this document means that the specific features, structures, or characteristics described in connection with the embodiment can 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 this 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 a corresponding implementable technical solution.

[0039] Unless otherwise defined, the meaning of technical terms used in this document is the same as that generally understood by those skilled in the art to which the present application belongs; the use of related terms in this document is only for the purpose of 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 a description of the logical relationship between the objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in this document generally represents that the associated objects before and after are a "or" logical relationship.

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

[0042] In this application, without more limitation, the "includes", "contains", "has" or other similar expressions used in the sentence are intended to cover non-exclusive inclusion, and these expressions do not exclude the presence of other elements in the process, method or product including the described elements, so that the process, method or product including a series of elements can not only include those limited elements, but also include other elements not explicitly listed, or also include the elements inherent in such process, method or product.

[0043] As the same understanding as in the "Guidelines for Examination", in this application, "greater than", "less than", "exceed" and other expressions are understood as not including the number; "above", "below", "within" and other expressions are understood to include the number. In addition, the meaning of "multiple" in the description of the embodiments of the present application is more than two (including two), and similar expressions related to "multiple" are also understood in this way, for example, "multiple groups", "multiple times" and the like, unless otherwise explicitly limited.

[0044] In the description of the embodiments of the present application, the spatially relative terms, such as "central", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship shown in the specific embodiment or the accompanying drawings, and are only used to facilitate the description of the specific embodiment of the present application or to facilitate the understanding of the reader, and do not indicate or imply that the indicated device or component must have a particular position, a particular orientation, or be constructed or operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0045] Unless otherwise expressly specified or limited, the terms "mount", "connect", "connection", "fixed", "set", and the like used in the description of the embodiments of the present application should be interpreted broadly. For example, the "connection" can be a fixed connection, or a detachable connection, or an integral setting; it can be a mechanical connection, or an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium; it can be a communication or interaction relationship between two elements. For those skilled in the art to which the present application belongs, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0046] Embodiment one:

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

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

[0049] A front group S1, an aperture stop T and a rear group S2 are sequentially arranged from the object side to the image side; the front group S1 and the rear group S2 both have positive focal power;

[0050] The front group S1 comprises a first lens G1 with positive focal power, a second lens G2 with negative focal power, a third lens G3 with positive focal power, a fourth lens G4 with positive focal power and a fifth lens G5 with negative focal power, which are sequentially arranged from the object side to the image side;

[0051] The rear group S2 comprises a sixth lens G6 with negative focal power, a seventh lens G7 with positive focal power, an eighth lens G8 with positive focal power and a ninth lens G9 with positive focal power, which are sequentially arranged 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 and f S2 satisfy the relationship: 1 < |f S1 / f S2 | < 3.

[0053] Further, 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 and f S1 satisfy 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 and f S1 satisfy 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 and f S1 satisfy the relationship: 2.5 < |f U2 / f S1 | < 3.5.

[0057] To realize the visible light and short wave infrared confocal, wide spectrum chromatic aberration balancing needs to be performed; in the embodiment, the first lens G1 adopts a material with high dispersion, which guides high-order chromatic aberration, and the first lens G1 and the first cemented lens group U1 are separated by a certain distance, the first cemented lens group U1 bears a small optical power, which is beneficial to correcting the wide spectrum chromatic aberration and provides a good foundation for correcting the aberration of the following lenses;

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

[0059] Further, 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 the astigmatism;

[0060] The focal length of the third cemented lens group U3 is f U3 , f U3 and f S2 satisfy 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 relation: 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 The relation 1.2 < |f is satisfied. 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 has a meniscus structure that bends towards the aperture stop, which can better balance spherical aberration and coma; the ninth lens G9 has a similar optical power to the eighth lens G8, which can better share the refractive effect and reduce off-axis aberration; the biconvex structure is beneficial for distortion correction and reducing the incident angle of the principal ray 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, which also provides favorable conditions for chromatic aberration balance.

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

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

[0070] Understandably, the aperture value of stop T needs to be adjusted according to the specific application scenario.

[0071] In addition, a beam-splitting prism P can be set between the first lens G1 and the second lens G2;

[0072] like Figure 1 As shown, the beam splitter 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 located on the refraction path of the beam splitter P; a coaxial illumination source or imaging system is also provided on the reflection path of the beam splitter P.

[0073] In this embodiment, the beam splitter P can be used to introduce an illumination component to form coaxial illumination, or to introduce other imaging components.

[0074] It should be noted that, in general, the beam splitter prism of a telecentric lens is placed in front of the aperture stop. When coaxial light is reflected by the lens in front of the aperture stop, stray light is formed, which creates bright spots on the image plane that cannot be eliminated, affecting the uniformity of brightness. However, in this embodiment of the invention, the beam splitter prism P is placed in front. On the one hand, this can effectively reduce stray light reflected by the lens, and on the other hand, it can increase the size of the beam splitter prism P to introduce a light source with a larger light-emitting area, thereby achieving a more uniform illumination effect.

[0075] To verify whether the optical system described above meets the design objectives, the following is a specific test example based on the above settings in 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, "front surface" corresponds to... Figure 1 The left surface of the lens or lens group corresponds to the middle surface, while the rear surface corresponds to the left surface. Figure 1 The right side surface of the corresponding lens or lens group; or it can be understood as: the object surface in Figure 1 On the left, the image plane (or image surface) is... Figure 1 On the right side, the surface closer to the object is called the "front surface", and the surface closer to the image is called the "back surface".

[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 element 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 = 598 mm; focal length f of the second cemented lens group U2 U2 = 112.7 mm; focal length f of the third cemented lens group U3 U3 = -18.4 mm; focal length f of the eighth lens G8 G8 = 29.6 mm; focal length f of the ninth lens G9 G9 = 27.8 mm;

[0082] Substituting the above values into each of the relational expressions, 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 relational expressions of the present embodiment are satisfied, i.e.:

[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 the present embodiment, the wavelength range to which the optical system is applied is 400 nm to 1000 nm,

[0087] Fig. 2 shows the MTF of the optical system of the present embodiment in the case of focusing at infinity. Figure 2 Fig. 3 shows the MTF of the optical system of the present embodiment in the case of focusing at 1000 mm. Figure 3 Fig. 4 shows the MTF of the optical system of the present embodiment in the case of focusing at 400 mm. Figure 4The focal point displacement of the optical system in the whole wavelength range is less than 40 microns, meeting the confocal use of visible light and short wave infrared.

[0088] Please refer to Figure 2 , Figure 3 and Figure 4 , Figure 2 is the MTF (Modulation Transfer Function) diagram of the white light wave band (436nm-700nm) of the optical system of the visible light and short wave infrared confocal telecentric lens provided by the embodiment of the application, Figure 3 is 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 application, Figure 4 is the multi-color light focal point displacement curve diagram of the optical system of the visible light and short wave infrared confocal telecentric lens provided by the embodiment of the application;

[0089] As Figure 2 and Figure 3 are the MTFs of the white light wave band and the short wave infrared wave band in the confocal case respectively; Figure 4 The focal point displacement of the optical system in the whole wavelength range is less than 40 microns, meeting the confocal use of visible light and short wave infrared.

[0090] The optical system of the visible light and short wave infrared confocal telecentric lens provided by the embodiment meets the application requirements of the confocal use of visible light and short wave infrared through reasonable lens combination design, material selection and focal length matching, and the focal point displacement in the wavelength range of 436nm-1000nm is less than 40 microns.

[0091] Embodiment two:

[0092] The embodiment provides a visible light and short wave infrared confocal telecentric lens, which comprises the optical system of the visible light and short wave infrared confocal telecentric lens as described in the embodiment one.

[0093] Based on the more detailed description of the optical system in the above embodiment, the description is not repeated in the embodiment.

[0094] In conclusion, the visible light and short wave infrared confocal telecentric lens provided by the embodiment of the application can meet the application requirements of the confocal use of visible light and short wave infrared.

[0095] The above-described embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalent replacements; 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 application.

Claims

1. An optical system for a confocal telecentric lens covering visible light and shortwave infrared, characterized in that, It consists of a front group S1, an aperture T, and a rear group S2 arranged sequentially from the object side to the image side; both the front group S1 and the rear group S2 have positive optical power. The front group S1 consists of 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 sequentially from the object side to the image side. The rear group S2 consists of 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 sequentially 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 relation: 1 < |f S1 / f S2 |<3; The second lens G2 and the third lens G3 form the first cemented lens group U1, and the fourth lens G4 and the fifth lens G5 form the second cemented lens group U2. The focal length of the first lens G1 is f G1 f G1 with f S1 Satisfies the relation: 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 The relation is satisfied: 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 relation: 2.5 < |f U2 / f S1 |<3.

5.

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

8.

3. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 2, 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.

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 made of high-dispersion glass, while the third lens G3, the fourth lens G4, the seventh lens G7, and the eighth lens G8 are all made of low-dispersion glass.

5. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 3, 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 the predetermined optical axis. The aperture of the stop T is a circular hole, and the center of the circular hole is on the predetermined optical axis.

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

7. The optical system of a visible light and short-wave infrared confocal telecentric lens according to claim 1, characterized in that, A beam-splitting 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 located on the refraction path of the beam splitter prism P; a coaxial illumination source or imaging system is also provided on the reflection path of the beam splitter prism P.

8. A confocal telecentric lens for visible light and shortwave infrared, characterized in that, The optical system includes a visible light and short-wave infrared confocal telecentric lens as described in any one of claims 1-7.

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