Endoscope coaxial holding system, coaxial optical system, and endoscope imaging system and use

Abstract

An endoscope coaxial holding system (1), a coaxial optical system (100), and an endoscope imaging system (200) and the use. The endoscope coaxial holding system (1) comprises a relay lens sheath (301), a connecting member (20) and an imaging lens sheath (101) successively arranged along the same optical axis from an image side; the relay lens sheath (301) and the imaging lens sheath (101) are optically coaxial, and the relay lens sheath (301) and the imaging lens sheath (101) respectively and oppositely abut against the radial outer wall and the radial inner wall of the connecting member (20) in the axial direction; an inner-layer lens sheath (41) and an outer-layer lens sheath (42) are successively and coaxially sleeved on the relay lens sheath (301) in the radial direction from the inside to the outside, and the outer-layer lens sheath (42) is axially separated relative to the inner-layer lens sheath (41); at least part of the outer-layer lens sheath (42) axially extends beyond an object-side end (1012) of the imaging lens sheath, and the outer-layer lens sheath (42) is radially separated from or radially connected to the connecting member (20).

Description

Endoscope coaxial holding system, coaxial optical system, endoscope imaging system and applications thereof

[0001] This application claims priority to a Chinese patent application filed on September 22, 2023, with application number 202311227346.0, and titled “Endoscope coaxial holding system, coaxial optical system, endoscope imaging system, and application thereof,” all contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the field of optical technology, and in particular to an endoscope coaxial holding system, a coaxial optical system, an endoscope imaging system and applications. Background Art

[0003] An endoscope is a device that uses a probe and optical lens to inspect and treat internal human tissue. Its operating principle is based on optical imaging and probe technology. By introducing a light source and lens into a body cavity or tissue, microscopic structures or diseased tissue within the body can be observed. The optical imaging principle of an endoscope involves light entering the body from a light source behind the body, being reflected by the inner wall of the endoscope head, and ultimately being guided by optical fibers to the observation device. The endoscope's optical lens focuses the light, forming a magnified image for the doctor to observe. Therefore, the quality of optical imaging directly affects the effectiveness of the endoscope.

[0004] The optical imaging of an endoscope is mainly achieved by the optical system installed inside it. The optical system is composed of an objective lens, a relay lens group and an eyepiece, which are arranged in sequence from the front end to the back end, with one end of the biological tissue as the front end. The objective lens is used to collect biological tissue information and form an image based on this, the relay lens group is used to transmit the image, and the eyepiece is used to magnify the image for observation by the clinician. The basis of optical imaging is the biological tissue information collected by the objective lens, so the collection of biological tissue information is an indispensable and important part. In order to ensure that the optical axes of the relay lens group and the objective lens group are coaxial, strict requirements are required on the relative positions of the lenses contained in the relay lens group and the objective lens group when they are installed.

[0005] However, it is difficult to maintain the overall stability of the mirror sheath in the existing technology, resulting in the optical axis between the rod mirror group and the objective lens group being easily offset due to accidental bumps or shaking during operation, thereby affecting the clarity of the image transmission of the rod mirror group.

[0006] In view of this, it is necessary to improve the optical system in the prior art to solve the above problems.

[0007] Summary of the Invention

[0008] The purpose of the present invention is to disclose an endoscope coaxial holding system, a coaxial optical system, an endoscope imaging system and their applications, which are used to solve the problem in the prior art that the overall stability of the optical system is low, resulting in reduced image transmission clarity due to accidental bumps or shaking during operation.

[0009] To achieve the above-mentioned object, in a first aspect, the present invention provides an endoscope coaxial holding system, comprising: a rotating mirror sheath, a connecting piece, and an imaging mirror sheath arranged in sequence along the optical axis from the image side;

[0010] The co-optical axis of the image-transmitting mirror sheath and the imaging mirror sheath is formed by the image-transmitting mirror sheath and the imaging mirror sheath respectively abutting against the radial outer wall and the radial inner wall of the connecting member in axial directions;

[0011] The image-relay mirror sheath is coaxially and radially outwardly provided with an inner mirror sheath and an outer mirror sheath in sequence, and the outer mirror sheath is axially separated from the inner mirror sheath;

[0012] The outer sheath at least partially extends axially beyond the object side end of the imaging sheath, the outer sheath is radially separated or radially connected to the connector, and a gap is formed between the outer sheath and the inner sheath for axial separation of the outer sheath relative to the inner sheath.

[0013] As a further improvement of the present invention, the connecting member is provided with an outer supporting portion convex radially outward for axially supporting the image transfer mirror sheath, and the connecting member is provided with a retaining portion concave radially inward for axially supporting the imaging mirror sheath and partially extending into the connecting member;

[0014] The rotating mirror sheath and the imaging mirror sheath have the same optical axis as each other, which is formed by the rotating mirror sheath and the imaging mirror sheath respectively abutting against the outer abutting portion and the retaining portion in opposite directions along the axial direction.

[0015] As a further improvement of the present invention, the outer mirror sheath is radially separated from at least part of the outer abutment portion;

[0016] The at least partial radial separation of the outer sheath and the outer abutment is formed by at least partial clearance fit or interference fit between the outer sheath and the outer abutment, so that the outer sheath can be axially separated relative to the outer abutment.

[0017] As a further improvement of the present invention, the outer mirror sheath is radially connected to at least a portion of the outer abutment portion;

[0018] The outer mirror sheath is fixedly connected to at least a portion of the outer supporting portion, so that the outer mirror sheath drives the connecting member to axially separate relative to the image relay mirror sheath.

[0019] As a further improvement of the present invention, a clearance fit or an interference fit is formed between the image-relay mirror sheath and the inner mirror sheath.

[0020] As a further improvement of the present invention, a first abutting surface formed by the relay mirror sheath axially abutting the outer abutting portion and a second abutting surface formed by the imaging mirror sheath axially abutting the retaining portion are axially spaced apart or located in the same radial plane of the optical axis.

[0021] In a second aspect, the present invention further provides a coaxial optical system comprising: an image transfer mechanism, a connecting member, and an imaging mechanism arranged in sequence along the optical axis from the image side;

[0022] The image transfer mechanism and the imaging mechanism share the same optical axis, formed by the image transfer mirror sheath contained in the image transfer mechanism and the imaging mirror sheath contained in the imaging mechanism being axially opposed to each other and respectively abutting against the radial outer wall and radial inner wall of the connecting member;

[0023] The image-relay mirror sheath is coaxially and radially outwardly provided with an inner mirror sheath and an outer mirror sheath in sequence, and the outer mirror sheath is axially separated from the inner mirror sheath;

[0024] The outer mirror sheath at least partially extends axially beyond the object side end of the imaging mirror sheath, and the outer mirror sheath is radially separated or radially connected to the connecting piece.

[0025] As a further improvement of the present invention, a gap is formed between the outer mirror sheath and the inner mirror sheath for axial separation of the outer mirror sheath relative to the inner mirror sheath.

[0026] As a further improvement of the present invention, the connecting member is provided with an outer supporting portion convex radially outward for axially supporting the image transfer mirror sheath, and the connecting member is provided with a retaining portion concave radially inward for axially supporting the imaging mirror sheath and partially extending into the connecting member;

[0027] The rotating mirror sheath and the imaging mirror sheath have the same optical axis as each other, which is formed by the rotating mirror sheath and the imaging mirror sheath respectively abutting against the outer abutting portion and the retaining portion in opposite directions along the axial direction.

[0028] As a further improvement of the present invention, the outer mirror sheath is radially separated from at least part of the outer abutment portion;

[0029] The at least partial radial separation of the outer sheath and the outer abutment is formed by at least partial clearance fit or interference fit between the outer sheath and the outer abutment, so that the outer sheath can be axially separated relative to the outer abutment.

[0030] As a further improvement of the present invention, the outer mirror sheath is radially connected to at least a portion of the outer abutment portion;

[0031] The outer mirror sheath is fixedly connected to at least a portion of the outer supporting portion, so that the outer mirror sheath drives the connecting member to axially separate relative to the image relay mirror sheath.

[0032] As a further improvement of the present invention, a first abutting surface formed by the relay mirror sheath axially abutting the outer abutting portion and a second abutting surface formed by the imaging mirror sheath axially abutting the retaining portion are axially spaced apart or located in the same radial plane of the optical axis.

[0033] As a further improvement of the present invention, the image relay mechanism comprises: an odd number of relay mirror groups greater than or equal to three arranged in the relay mirror sheath at intervals along the same optical axis, and a plurality of first isolation rings axially supported between adjacent relay mirror groups;

[0034] The image-transmitting lens group is symmetrically composed of two rod-shaped lens groups.

[0035] As a further improvement of the present invention, the outer abutting portion forms a limiting end that at least partially extends axially into the image-transmitting mirror sheath, and the limiting end axially abuts against the rod-shaped lens assembly inside the object-side end of the image-transmitting mirror sheath.

[0036] As a further improvement of the present invention, at least one annular groove is formed circumferentially at the limiting end, and a filling layer is embedded in the annular groove to prevent the image relay sheath from being axially separated from the connecting piece.

[0037] As a further improvement of the present invention, the filling layer is an adhesive medium or a sealing medium.

[0038] As a further improvement of the present invention, the connecting member is constructed with an axially arranged connecting channel, the imaging mirror sheath is partially accommodated in the connecting channel, and the connecting channel protrudes radially inward to form the retaining portion for axially supporting the imaging mirror sheath.

[0039] As a further improvement of the present invention, a clearance fit or an interference fit is formed between the image-relay mirror sheath and the inner mirror sheath.

[0040] As a further improvement of the present invention, the imaging mechanism includes: a first lens group with positive refractive power, a second lens group with positive refractive power, a third lens group with positive refractive power, and a fourth lens group with positive refractive power, which are arranged in sequence on the same optical axis from the object side;

[0041] The first lens group includes a second lens having a flat surface facing the object side, the second lens group includes a fourth lens having a convex surface facing the object side and a fifth lens having a convex surface facing the image side, the third lens group includes a sixth lens having a convex surface facing the object side and a concave surface facing the image side, and the fourth lens group includes a seventh lens having a concave surface facing the object side and a convex surface facing the image side, and an eighth lens having a convex surface facing the object side and a concave surface facing the image side.

[0042] The combined focal length f1 of the first lens group and the conjugate distance T satisfy 0.15≤f1 / T≤0.18, the combined focal length f4 of the fourth lens group and the combined focal length f1 of the first lens group satisfy 1.8≤f4 / f1≤2.2, and the focal length f of the seventh lens is 41 The focal length f of the eighth lens 42 Satisfy -1≤f 42 / f 41 ≤-0.8.

[0043] As a further improvement of the present invention, the first lens group further includes: a third lens arranged on the image side of the second lens with the same optical axis;

[0044] The surface of the third lens facing the image side is formed into a convex surface.

[0045] As a further improvement of the present invention, the first lens group further includes: a first lens which is arranged on the object side of the second lens with the same optical axis and has a plane facing the object side.

[0046] As a further improvement of the present invention, the outer mirror sheath axially extends over the object side end of the imaging mirror sheath to form a protective end, and the first lens is coaxially arranged in the protective end.

[0047] As a further improvement of the present invention, the coaxial optical system further includes:

[0048] The mirror seat is arranged at the side end of the outer mirror sheath and forms a detachable adapter seat with the mirror seat.

[0049] As a further improvement of the present invention, the mirror seat is constructed with an accommodating channel for accommodating at least a portion of the image-transmitting mirror sheath, and the accommodating channel forms a stepped recess radially inward for axially supporting the image-side end of the image-transmitting mirror sheath.

[0050] As a further improvement of the present invention, the inner mirror sheath axially passes through the adapter and extends into the mirror base to abut against the step recess formed by the mirror base, and the inner mirror sheath is axially abutted between the mirror base and the outer abutting portion.

[0051] In a third aspect, the present invention also provides an endoscopic imaging system, comprising: a mirror holder having a dichroic mirror, a light source, and a coaxial optical system as described in any one of the second aspects; the mirror holder contained in the coaxial optical system is configured to receive incident light from the light source incident on the dichroic mirror, and the reflected light formed from the object to be measured is captured by the coaxial optical system after being reflected by the dichroic mirror, and the reflected light passes through the dichroic mirror to be captured by the endoscopic imaging system.

[0052] In a fourth aspect, the present invention further provides an application of an endoscopic imaging system, which uses the endoscopic imaging system as described in the third aspect to perform optical imaging of biological tissue.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] The rotating mirror sheath and the imaging mirror sheath are mounted and fixed by a connector so that the axis of the rotating mirror sheath coincides with the axis of the imaging mirror sheath and lies on the same optical axis, thereby achieving coaxiality between the rotating mirror sheath and the imaging mirror sheath, thereby ensuring clarity of image transmission when optically imaging biological tissue. Furthermore, the outer mirror sheath and the inner mirror sheath are assembled compactly along the radial direction to prevent the outer mirror sheath from shaking relative to the inner mirror sheath during assembly and disassembly or operation, thereby improving the overall stability of the endoscope's coaxial maintenance system and preventing the axis between the rotating mirror sheath and the imaging mirror sheath from shifting due to the operator's accidental bumping of the outer mirror sheath or shaking during operation, thereby ensuring that the rotating mechanism and the imaging mechanism always maintain coaxiality. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] FIG1 is a cross-sectional view of an endoscope coaxial holding system disclosed in the present invention;

[0056] FIG2 is a cross-sectional view of the coaxial optical system disclosed in the present invention;

[0057] FIG3 is a cross-sectional view of an endoscopic imaging system including a coaxial optical system disclosed in the present invention;

[0058] FIG4 is a partial enlarged view of the circle B in FIG1 ;

[0059] FIG5 is a partial enlarged view of the circle C in FIG2;

[0060] FIG6 is a partial enlarged view of circle D in FIG2 ;

[0061] FIG7 is a partial enlarged view of the dotted box E in FIG2 ;

[0062] FIG8 is a schematic diagram of a first lens and a second lens in a modified embodiment;

[0063] FIG9 is a cross-sectional structure of the imaging mechanism in FIG2 and FIG3 including the optical axis A, wherein the first lens, the second lens, and the third lens are combined to form a first lens group;

[0064] FIG10 is an MTF curve diagram of the imaging mechanism in Example 1 under a field of view of 1.0;

[0065] FIG11 is an MTF curve diagram of the imaging mechanism in Example 1 at a field of view of 0.707;

[0066] FIG12 is an MTF curve diagram of the imaging mechanism in the central field of view in Example 1;

[0067] FIG13 is a Siemens Star card diagram of the imaging mechanism in Example 1;

[0068] FIG14 is an MTF curve diagram of the imaging mechanism in Example 2 at a field of view of 0.707;

[0069] FIG15 is an MTF curve diagram of the imaging mechanism in Example 2 at a field of view of 1.0;

[0070] FIG16 is an MTF curve diagram of the imaging mechanism in the center field of view in Example 2;

[0071] FIG17 is a Siemens Star card diagram of the imaging mechanism in Example 2;

[0072] FIG18 is an MTF curve diagram of the imaging mechanism in Example 3 at a field of view of 0.707;

[0073] FIG19 is an MTF curve diagram of the imaging mechanism in Example 3 at a field of view of 1.0;

[0074] FIG20 is an MTF curve diagram of the imaging mechanism in the central field of view in Example 3;

[0075] FIG21 is a Siemens Star card diagram of the imaging mechanism in Example 3. DETAILED DESCRIPTION

[0076] The present invention is described in detail below with reference to the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in this field based on these embodiments are all within the scope of protection of the present invention.

[0077] It should be noted that, in the following embodiments, the term "optical axis" refers to the optical axis A in Figure 1. The term "axial" refers to the direction parallel to the optical axis A. Under the viewing angles shown in Figures 1 to 3, as shown in Figure 3, the direction of the object W to be measured is the object side, and the direction opposite to the object W to be measured is the image side. At the same time, for the convenience of explanation, the lenses contained in the coaxial optical system are defined as optical elements, and in actual application scenarios (for example, the following endoscope is used to observe a living organism), before the organism is imaged using the organism imaging system, the end of the organism imaging system close to the object side is immersed in physiological saline to form a layer of physiological saline at the end, and for the convenience of explanation of the following embodiments, in this application, physiological saline can also be defined as an optical element. The object W to be measured includes a living organism or an in vitro biological tissue.

[0078] The "MTF" in the "MTF curve diagram" of the present invention stands for Modulation Transfer Function, in which the horizontal axis represents the spatial frequency (in cycles per millimeter) and the vertical axis represents the contrast of the image at the corresponding frequency.

[0079] Please refer to FIG. 1 to FIG. 21 for specific embodiments of the endoscope coaxial holding system, coaxial optical system, endoscope imaging system, and applications.

[0080] As shown in Figures 1 and 4, the endoscope coaxial holding system 1 can be installed on an optical detection device used to observe a biological body (including a living organism or an in vitro biological tissue). The endoscope coaxial holding system 1 is used to accommodate a rod lens group and an objective lens group and to make the rod lens group and the objective lens group coaxial, and can prevent the operator (for example, a medical staff or a scientific researcher) from accidentally bumping or shaking during operation, which causes the axis between the rod lens group and the objective lens group to shift, thereby ensuring that the image plane formed by the objective lens group optically imaging the biological tissue can ensure image clarity when transmitted through the rod lens group, thereby allowing the operator to observe the biological image. Specifically, the optical detection device can be, for example, an endoscope. An endoscope is a tool for minimally invasive medical treatment of the human body, which is designed to enter the human body through the natural cavity of the human body or a small incision during surgery, and guide the endoscope into the biological tissue to be inspected to obtain the corresponding image of the biological tissue to be inspected for observation by medical personnel. At the same time, the applicant points out that in the following description, an endoscope is used as an example for exemplary explanation. Of course, it can also be an equipment used for flaw detection in the industrial field. This embodiment does not limit this, but this cannot limit the scope of protection of this application.

[0081] As shown in Figures 1 and 4, in this embodiment, the endoscope coaxial holding system 1 includes: a rotating mirror sheath 301, a connecting piece 20 and an imaging mirror sheath 101 are arranged in sequence on the same optical axis from the image side; the rotating mirror sheath 301 and the imaging mirror sheath 101 are on the same optical axis because the rotating mirror sheath 301 and the imaging mirror sheath 101 are axially opposed to each other and respectively abut against the radial outer wall and radial inner wall of the connecting piece 20; the rotating mirror sheath 301, the connecting piece 20 and the imaging mirror sheath 101 are arranged in sequence on the same optical axis from the image side, the connecting piece 20 is arranged at the object side end 3012 of the rotating mirror sheath, and the imaging mirror sheath 101 is arranged at the object side end 24 of the connecting piece, and the rotating mirror sheath 301 and the imaging mirror sheath 101 are axially opposed to each other and abut against the connecting piece 20. Specifically, the image transfer mirror sheath 301 axially abuts against the radial outer wall of the connector 20, the connector 20 is installed at the object side end 3012 of the image transfer mirror sheath, and the imaging mirror sheath 101 axially abuts against the radial inner wall of the connector 20 and is installed at the object side end 24 of the connector. The image transfer mirror sheath 301 and the imaging mirror sheath 101 are installed and fixed by the connector 20 so that the axis of the image transfer mirror sheath 301 coincides with the axis of the imaging mirror sheath 101 and is on the same optical axis A, thereby achieving the same optical axis as the imaging mirror sheath 101 to ensure the clarity of image transmission.

[0082] The inner mirror sheath 41 and the outer mirror sheath 42 are coaxially and radially outwardly arranged on the rotating mirror sheath 301, and the outer mirror sheath 42 is axially separated from the inner mirror sheath 41; the outer mirror sheath 42 is disassembled and assembled relative to the inner mirror sheath 41, and the outer mirror sheath 42 and the inner mirror sheath 41 are assembled compactly along the radial direction to prevent the outer mirror sheath 42 from shaking relative to the inner mirror sheath 41 during disassembly or operation, thereby improving the overall stability of the endoscope coaxial holding system 1, and preventing the operator from accidentally bumping the outer mirror sheath 42 or shaking during operation, which may cause the axis between the rotating mirror sheath 301 and the imaging mirror sheath 101 to deviate, thereby ensuring that the rotating mirror sheath 301 and the imaging mirror sheath 101 can always maintain the same optical axis.

[0083] The outer sheath 42 at least partially extends axially past the object-side end 1012 of the imaging sheath. The inner sheath 41 is coaxially sleeved on the outside of the rotating image sheath 301, and the outer sheath 42 is coaxially sleeved on the outside of the inner sheath 41. The outer sheath 42 is sleeved on the outside of the connector 20 and the imaging sheath 101 and at least partially extends axially past the object-side end 1012 of the imaging sheath. The outer sheath 42 protects the rotating image sheath 301, the connector 20, and the imaging sheath 101, preventing them from coming into direct contact with the outside world.

[0084] The outer mirror sheath 42 is radially separated from or radially connected to the connecting member 20. The outer mirror sheath 42 is radially separated from the connecting member 20 to facilitate the outer mirror sheath 42 to be assembled and disassembled relative to the connecting member 20, or the outer mirror sheath 42 is radially connected to the connecting member 20 to facilitate the outer mirror sheath 42 to synchronously drive the connecting member 20 to be assembled and disassembled relative to the rotating mirror sheath 301.

[0085] As shown in FIG4 , a gap 401 is formed between the outer sheath 42 and the inner sheath 41 for axial separation of the outer sheath 42 relative to the inner sheath 41. The outer sheath 42 and the inner sheath 41 are assembled compactly along the radial direction, and the gap 401 is formed between the outer sheath 42 and the inner sheath 41. This improves the overall stability of the endoscope coaxial holding system 1 while allowing the outer sheath 42 to be axially separated from the inner sheath 41, thereby facilitating assembly and disassembly of the outer sheath 42 relative to the inner sheath 41 and preventing the outer sheath 42 from shaking relative to the inner sheath 41 during assembly and disassembly or operation.

[0086] A clearance fit or an interference fit is formed between the image-transmitting sheath 301 and the inner sheath 41. The image-transmitting sheath 301 and the inner sheath 41 are assembled compactly in the radial direction, and a clearance (not shown) is formed between the outer circumferential wall of the image-transmitting sheath 301 and the inner circumferential wall of the inner sheath 41 in the radial direction. Alternatively, an interference fit is formed between the outer circumferential wall of the image-transmitting sheath 301 and the inner circumferential wall of the inner sheath 41 in the radial direction (not shown). Alternatively, as shown in FIG. 4 , the outer circumferential wall of the image-transmitting sheath 301 and the inner circumferential wall of the inner sheath 41 are in close contact with each other. Any of these options are acceptable as long as the image-transmitting sheath 301 and the inner sheath 41 are assembled compactly in the radial direction and the inner sheath 41 can be axially separated from the image-transmitting sheath 301 for assembly and disassembly.

[0087] As shown in Figures 1 and 4, the connecting member 20 is provided with an outer abutting portion 21 that protrudes radially outward and is axially abutted by the rotating mirror sheath 301, and the connecting member 20 is provided with a retaining portion 22 that is axially abutted by the imaging mirror sheath 101 and partially extends into the connecting member 20; the rotating mirror sheath 301 and the imaging mirror sheath 101 are coaxial in the sense that the rotating mirror sheath 301 and the imaging mirror sheath 101 respectively abut against the outer abutting portion 21 and the retaining portion 22 in opposite directions along the axial direction. The connecting piece 20 is radially outwardly convex to form an outer supporting portion 21, and the image transfer mirror sheath 301 is axially supported by the outer supporting portion 21. The connecting piece 20 is radially inwardly concave to form a retaining portion 22, and the imaging mirror sheath 101 is axially supported and partially extends into the retaining portion 22. The image transfer mirror sheath 301 and the imaging mirror sheath 101 are axially opposed to each other and respectively supported by the outer supporting portion 21 and the retaining portion 22. The connecting piece 20 is arranged at the object side end 3012 of the image transfer mirror sheath through the outer supporting portion 21, and the imaging mirror sheath 101 is arranged at the object side end 24 of the connecting piece through the retaining portion 22. The connecting piece 20 respectively installs and fixes the image transfer mirror sheath 301 and the imaging mirror sheath 101 through the outer supporting portion 21 and the retaining portion 22, so that the axis of the image transfer mirror sheath 301 coincides with the axis of the imaging mirror sheath 101 and is on the same optical axis A, thereby achieving the same optical axis as the imaging mirror sheath 101, so as to ensure the clarity of image transmission.

[0088] In some embodiments, the outer sheath 42 is radially separated from at least a portion of the outer abutment portion 21. When the object-side end 24 of the connector tilts inward toward the optical axis A to form a conical shape, the outer sheath 42 is radially separated from at least a portion of the outer circumferential wall of the outer abutment portion 21, as shown in FIG5 . In some embodiments, the outer sheath 42 may also be radially separated from the entire outer circumferential wall of the outer abutment portion 21 (not shown). The at least partial radial separation of the outer sheath 42 from the outer abutment portion 21 is achieved by at least a partial clearance fit or interference fit between the outer sheath 42 and the outer abutment portion 21, allowing the outer sheath 42 to be axially separated relative to the outer abutment portion 21. The outer sheath 42 may form a clearance fit with at least a portion of the outer circumferential wall of the outer abutment portion 21, as shown in FIG4 . In some embodiments, the outer sheath 42 may also form an interference fit with at least a portion of the outer circumferential wall of the outer abutment portion 21 (not shown). In this embodiment, preferably, the outer sheath 42 forms a clearance fit with at least a portion of the outer circumferential wall of the outer abutment portion 21. The outer mirror sheath 42 forms a clearance fit or an interference fit with at least a portion of the outer peripheral wall of the outer abutment portion 21. The outer mirror sheath 42 can be tilted inwardly toward the optical axis A to form a conical connector object-side end 24. The outer mirror sheath 42 is assembled to the outside of the connector 20 from the connector object-side end 24 toward the image side. The conical connector object-side end 24 facilitates interference fit between the outer mirror sheath 42 and the connector 20. The conical connector object-side end 24 reduces the press-fit distance between the outer mirror sheath 42 and the connector 20 during interference fit, facilitating assembly and disassembly of the outer mirror sheath 42 and preventing scratches on the mating surface between the outer mirror sheath 42 and the connector 20 during assembly and disassembly of the outer mirror sheath 42. It should be noted that the interference fit assembly method between the outer mirror sheath 42 and the connector 20 can be, but is not limited to, a press-fit method, a temperature difference method, and a hydraulic method.

[0089] In some embodiments, the outer sheath 42 is radially connected to at least a portion of the outer abutment portion 21. When the object-side end 24 of the connector tilts inward toward the optical axis A to form a cone, the outer sheath 42 is radially connected to at least a portion of the outer circumferential wall of the outer abutment portion 21, as shown in FIG5 . In some embodiments, the outer sheath 42 can also be radially separated from the entire outer circumferential wall of the outer abutment portion 21 (not shown). The outer sheath 42 is fixedly connected to at least a portion of the outer abutment portion 21, allowing the outer sheath 42 to drive the connector 20 to axially separate relative to the image-transmitting sheath 301. The outer sheath 42 and at least a portion of the outer circumferential wall of the outer abutment portion 21 can be fixedly connected using, but not limited to, laser welding or an adhesive medium. This allows the outer sheath 42 to drive the connector 20 to axially separate relative to the image-transmitting sheath 301 for assembly and disassembly. When the outer mirror sheath 42 is fixedly connected to at least part of the outer peripheral wall of the outer supporting portion 21 , preferably, the outer diameter of the inner mirror sheath 41 is smaller than the outer diameter of the connector 20 to avoid friction between the outer mirror sheath 42 and the inner mirror sheath 41 during assembly and disassembly.

[0090] Based on the endoscope coaxial holding system 1 disclosed in the aforementioned embodiment, this embodiment further discloses a coaxial optical system 100 .

[0091] As shown in Figures 2, 5 and 6, the coaxial optical system 100 can be installed in an optical detection device used to observe a biological body (including a living organism or an in vitro biological tissue), and specifically forms an insertion portion of the optical detection device and enables the image transfer mechanism 30 and the imaging mechanism 10 to achieve the same optical axis, so as to be inserted into the body of the biological body to be inspected to perform optical imaging of the biological tissue, and can prevent the operator (for example, medical personnel or scientific researchers) from accidentally bumping or shaking during operation, which causes the axis between the image transfer mechanism 30 and the imaging mechanism 10 to shift, thereby ensuring that the image plane formed by the imaging mechanism 10 for optical imaging of the biological tissue can ensure image clarity when transmitted through the image transfer mechanism 30, thereby allowing the operator to observe the biological image. Specifically, the optical detection device can be, for example, an endoscope, which is a tool for minimally invasive medical treatment of the human body, designed to enter the human body through the natural cavity of the human body or a small incision during surgery, and guide the endoscope into the biological tissue to be inspected to obtain the corresponding image of the biological tissue to be inspected for observation by medical personnel. At the same time, the applicant points out that in the following description, an endoscope is used as an example for exemplary explanation. Of course, it can also be an equipment used for flaw detection in the industrial field. This embodiment does not limit this, but this cannot limit the scope of protection of this application.

[0092] The coaxial optical system 100 includes: a relay mechanism 30, a connector 20, and an imaging mechanism 10, arranged coaxially from the image side. The relay mechanism 30 and the imaging mechanism 10 are coaxially formed by the relay lens sheath 301 contained in the relay mechanism 30 and the imaging lens sheath 101 contained in the imaging mechanism 10, respectively abutting against the radially outer and radially inner walls of the connector 20 in axially opposing directions. The relay mechanism 30, the connector 20, and the imaging mechanism 10 are arranged coaxially from the image side, with the connector 20 disposed at the object-side end 3012 of the relay lens sheath and the imaging lens sheath 101 disposed at the object-side end 24 of the connector. The relay mechanism 30 and the imaging mechanism 10 are axially abutted against the connector 20 in axially opposing directions. Specifically, the image transfer sheath 301 and the imaging mirror sheath 101 are axially opposed to each other and abutted against the connecting piece 20, the image transfer sheath 301 axially abuts against the radial outer wall of the connecting piece 20, the connecting piece 20 is installed at the object side end 3012 of the image transfer sheath, and the imaging mirror sheath 101 axially abuts against the radial inner wall of the connecting piece 20 and is installed at the object side end 24 of the connecting piece. The image transfer sheath 301 and the imaging mirror sheath 101 are installed and fixed by the connecting piece 20 so that the axis of the image transfer sheath 301 coincides with the axis of the imaging mirror sheath 101 and is on the same optical axis A, thereby realizing that the image transfer mechanism 30 and the imaging mechanism 10 have the same optical axis, and thereby ensuring that the image plane formed by the optical imaging of the biological tissue by the imaging mechanism 10 can ensure image clarity when it is transmitted through the image transfer mechanism 30.

[0093] The inner mirror sheath 41 and the outer mirror sheath 42 are coaxially and radially outwardly arranged on the image-transmitting mirror sheath 301, and the outer mirror sheath 42 is axially separated from the inner mirror sheath 41. The outer mirror sheath 42 is disassembled and assembled relative to the inner mirror sheath 41, and the outer mirror sheath 42 and the inner mirror sheath 41 are assembled compactly along the radial direction to prevent the outer mirror sheath 42 from shaking relative to the inner mirror sheath 41 during disassembly or operation, thereby improving the overall stability of the coaxial optical system 100 and preventing the axis between the image-transmitting mirror sheath 301 and the imaging mirror sheath 101 from shifting due to the operator's accidental bumping of the outer mirror sheath 42 or shaking during operation, thereby ensuring that the image-transmitting mirror sheath 301 and the imaging mirror sheath 101 can always maintain the same optical axis.

[0094] The outer sheath 42 at least partially extends axially beyond the object-side end 1012 of the imaging mirror sheath. The inner sheath 41 is coaxially sleeved on the outside of the image transfer mirror sheath 301, and the outer sheath 42 is coaxially sleeved on the outside of the inner sheath 41. The outer sheath 42 is sleeved on the outside of the connector 20 and the imaging mirror sheath 101 and at least partially extends axially beyond the object-side end 1012 of the imaging mirror sheath. The outer sheath 42 can protect the image transfer mirror sheath 301, the connector 20, and the imaging mirror sheath 101, thereby preventing the image transfer mirror sheath 301, the connector 20, and the imaging mirror sheath 101 from direct contact with the outside world.

[0095] The outer mirror sheath 42 is radially separated from or radially connected to the connecting member 20. The outer mirror sheath 42 is radially separated from the connecting member 20 to facilitate the outer mirror sheath 42 to be assembled and disassembled relative to the connecting member 20, or the outer mirror sheath 42 is radially connected to the connecting member 20 to facilitate the outer mirror sheath 42 to synchronously drive the connecting member 20 to be assembled and disassembled relative to the rotating mirror sheath 301.

[0096] As shown in Figures 2 and 5, a gap 401 is further formed between the outer sheath 42 and the inner sheath 41, allowing the outer sheath 42 to be axially separated from the inner sheath 41. The outer sheath 42 and the inner sheath 41 are assembled compactly in the radial direction, and the gap 401 is formed between the outer sheath 42 and the inner sheath 41. This improves the overall stability of the coaxial optical system 100 while allowing the outer sheath 42 to be axially separated from the inner sheath 41, thereby facilitating assembly and disassembly of the outer sheath 42 relative to the inner sheath 41 and preventing the outer sheath 42 from shaking relative to the inner sheath 41 during assembly and disassembly or operation.

[0097] A clearance fit or an interference fit is formed between the image-transmitting sheath 301 and the inner sheath 41. The image-transmitting sheath 301 and the inner sheath 41 are assembled compactly in the radial direction, and a clearance (not shown) is formed between the outer circumferential wall of the image-transmitting sheath 301 and the inner circumferential wall of the inner sheath 41 in the radial direction. Alternatively, an interference fit is formed between the outer circumferential wall of the image-transmitting sheath 301 and the inner circumferential wall of the inner sheath 41 in the radial direction (not shown). Alternatively, as shown in FIG. 4 , the outer circumferential wall of the image-transmitting sheath 301 and the inner circumferential wall of the inner sheath 41 are in close contact with each other. Any of these options are acceptable as long as the image-transmitting sheath 301 and the inner sheath 41 are assembled compactly in the radial direction and the inner sheath 41 can be axially separated from the image-transmitting sheath 301 for assembly and disassembly.

[0098] As shown in Figures 2 and 5, specifically, the connecting member 20 is provided with an outer abutting portion 21 that protrudes radially outward and is axially abutted by the rotating mirror sheath 301, and the connecting member 20 is provided with a retaining portion 22 that is axially abutted by the imaging mirror sheath 101 and partially extends into the connecting member 20; the rotating mirror sheath 301 and the imaging mirror sheath 101 have the same optical axis as each other, which is formed by the rotating mirror sheath 301 and the imaging mirror sheath 101 respectively abutting against the outer abutting portion 21 and the retaining portion 22 in opposite directions along the axial direction. The connecting piece 20 is radially outwardly convex to form an outer supporting portion 21, and the image transfer mirror sheath 301 is axially supported on the outer supporting portion 21. The connecting piece 20 is radially inwardly concave to form a retaining portion 22, and the imaging mirror sheath 101 is axially supported and partially extends into the retaining portion 22. The image transfer mirror sheath 301 and the imaging mirror sheath 101 are axially opposed to each other and are respectively supported on the outer supporting portion 21 and the retaining portion 22. The connecting piece 20 is arranged on the object side end 3012 of the image transfer mirror sheath through the outer supporting portion 21, and the imaging mirror sheath 101 is retained by the retaining portion 22. The portion 22 is provided at the object side end 24 of the connector, and the connector 20 installs and fixes the rotating mirror sheath 301 and the imaging mirror sheath 101 through the external supporting portion 21 and the retaining portion 22, so that the axis of the rotating mirror sheath 301 coincides with the axis of the imaging mirror sheath 101 and is on the same optical axis A, thereby realizing that the rotating mechanism 30 and the imaging mechanism 10 are on the same optical axis, and thus ensuring that the image plane formed by the optical imaging of the biological tissue by the imaging mechanism 10 can ensure image clarity when it is transmitted through the rotating mechanism 30.

[0099] As shown in FIG5 , in some embodiments, the outer sheath 42 is radially separated from at least a portion of the outer abutment portion 21. When the object-side end 24 of the connector tilts inward toward the optical axis A to form a conical shape, the outer sheath 42 is radially separated from at least a portion of the outer circumferential wall of the outer abutment portion 21, as shown in FIG5 . In some embodiments, the outer sheath 42 may also be radially separated from the entire outer circumferential wall of the outer abutment portion 21 (not shown). The at least partial radial separation of the outer sheath 42 from the outer abutment portion 21 is achieved by at least a partial clearance fit or interference fit between the outer sheath 42 and the outer abutment portion 21, allowing the outer sheath 42 to be axially separated relative to the outer abutment portion 21. The outer sheath 42 may form a clearance fit with at least a portion of the outer circumferential wall of the outer abutment portion 21, as shown in FIG5 . In some embodiments, the outer sheath 42 may also form an interference fit with at least a portion of the outer circumferential wall of the outer abutment portion 21 (not shown). In this embodiment, the outer mirror sheath 42 preferably forms a clearance fit with at least a portion of the outer circumferential wall of the outer abutting portion 21. Whether the outer mirror sheath 42 forms a clearance fit or an interference fit with at least a portion of the outer circumferential wall of the outer abutting portion 21, the outer mirror sheath 42 can be tilted inwardly toward the optical axis A to form a conical connector object-side end 24. The outer mirror sheath 42 is assembled to the outside of the connector 20 from the connector object-side end 24 toward the image side. The conical connector object-side end 24 facilitates interference fit between the outer mirror sheath 42 and the connector 20. The conical connector object-side end 24 reduces the press-fit distance between the outer mirror sheath 42 and the connector 20 during interference fit, facilitating assembly and disassembly of the outer mirror sheath 42 and preventing scratches on the interface between the outer mirror sheath 42 and the connector 20 during assembly and disassembly of the outer mirror sheath 42. It should be noted that the interference fit assembly method between the outer mirror sheath 42 and the connector 20 may include, but is not limited to, a press-in method, a temperature difference method, and a hydraulic method.

[0100] As shown in FIG5 , in some embodiments, the outer sheath 42 is radially connected to at least a portion of the outer abutment portion 21. When the object-side end 24 of the connector tilts inward toward the optical axis A to form a conical shape, the outer sheath 42 is radially connected to at least a portion of the outer circumferential wall of the outer abutment portion 21, as shown in FIG5 . In some embodiments, the outer sheath 42 can also be radially separated from the entire outer circumferential wall of the outer abutment portion 21 (not shown). The outer sheath 42 is fixedly connected to at least a portion of the outer abutment portion 21, allowing the outer sheath 42 to drive the connector 20 to axially separate relative to the image-transmitting sheath 301. The outer sheath 42 and at least a portion of the outer circumferential wall of the outer abutment portion 21 can be fixedly connected using, but not limited to, laser welding or an adhesive medium. This allows the outer sheath 42 to drive the connector 20 to axially separate relative to the image-transmitting sheath 301 for assembly and disassembly. When the outer mirror sheath 42 is fixedly connected to at least part of the outer peripheral wall of the outer supporting portion 21 , preferably, the outer diameter of the inner mirror sheath 41 is smaller than the outer diameter of the connector 20 to avoid friction between the outer mirror sheath 42 and the inner mirror sheath 41 during assembly and disassembly.

[0101] As shown in FIG5 , a first abutting surface 3011 formed by the outer abutting portion 21 of the image relay sheath 301 and a second abutting surface 1011 formed by the axial abutting retaining portion 22 of the imaging mirror sheath 101 are axially spaced apart or lie in the same radial plane relative to the optical axis A. The first abutting surface 3011 and the second abutting surface 1011 are axially spaced apart, and the second abutting surface 1011 is located toward the object side of the first abutting surface 3011, as shown in FIG5 . In some embodiments, the second abutting surface 1011 may also be located toward the image side of the first abutting surface 3011 (not shown), or the first abutting surface 3011 and the second abutting surface 1011 may lie in the same radial plane relative to the optical axis A (not shown). Any such arrangement is acceptable as long as the image relay mechanism 30 and the imaging mechanism 10 are coaxial to ensure clarity of the image relay mechanism 30's transmission of the imaged surface of the imaging mechanism 10.

[0102] As shown in Figures 5 and 6, the image relay mechanism 30 includes an odd number of three or more relay lens groups 31 disposed within a relay lens sheath 301 at intervals along the same optical axis, and a plurality of first isolation rings 32 axially supported between adjacent relay lens groups 31. The relay lens groups 31 are symmetrically formed from two rod lens groups 311. The odd number of three or more relay lens groups 31 is used to transmit an erect real image. The first isolation rings 32 secure the rod lens groups 311 in place, maintaining the axial distances between the rod lens groups 311, preventing displacement within the relay lens sheath 301, and ensuring that the rod lens groups 311 are aligned along the same optical axis.

[0103] As shown in FIG5 , the outer abutting portion 21 forms a limiting end 211 that at least partially extends axially into the rotating mirror sheath 301. The limiting end 211 axially abuts against the rod-shaped lens assembly 311 within the object-side end 3012 of the rotating mirror sheath. The rotating mirror sheath 301 axially abuts the outer abutting portion 21. The outer abutting portion 21 forms a limiting end 211 that at least partially extends axially into the rotating mirror sheath 301. The connector 20 is axially mounted to the object-side end 3012 of the rotating mirror sheath via the limiting end 211. The limiting end 211 axially abuts against the rod-shaped lens assembly 311 within the object-side end 3012 of the rotating mirror sheath, thereby cooperating with the first isolation ring 32 to secure the multiple rod-shaped lens assembly 311 within the rotating mirror sheath 301, thereby stabilizing the axial distance between the multiple rod-shaped lens assembly 311 within the rotating mirror sheath 301.

[0104] As shown in FIG5 , in this embodiment, the limiting end 211 preferably forms at least one annular groove 2111 circumferentially. This annular groove 2111 contains a filling layer that prevents axial separation of the image-transmitting mirror sheath 301 and the connecting member 20. The filling layer is an adhesive or sealing medium. By inserting the adhesive or sealing medium into the annular groove 2111, the connecting member 20 is mounted on the object-side end 3012 of the image-transmitting mirror sheath, preventing axial separation of the image-transmitting mirror sheath 301 and the connecting member 20 due to external forces, thereby improving the stability of the assembly of the image-transmitting mirror sheath 301 and the connecting member 20. It should be noted that the adhesive medium is preferably optical adhesive, and the sealing medium is preferably a sealing ring, such as an O-ring.

[0105] As shown in Figure 5, specifically, the connector 20 is constructed with an axially arranged connecting channel 23. The imaging mirror sheath 101 is partially accommodated within the connecting channel 23. The connecting channel 23 has a radially inwardly projecting retaining portion 22 that provides axial support for the imaging mirror sheath 101. The connector 20 is constructed with a connecting channel 23 that accommodates at least a portion of the imaging mirror sheath 101. The connecting channel 23 is radially inwardly projecting to form a retaining portion 22 that provides axial support for the imaging mirror sheath 101, thereby allowing the imaging mirror sheath 101 to be installed within the connecting channel 23. The imaging mirror sheath 101 and the object-side end 24 of the connector can be fixedly connected by, but not limited to, laser welding or an adhesive medium.

[0106] As shown in FIG9 , the imaging mechanism 10 includes: a first lens group 11 having positive optical power, a second lens group 12 having positive optical power, a third lens group 13 having positive optical power, and a fourth lens group 14 having positive optical power, which are arranged in sequence from the object side along the optical axis (i.e., optical axis A shown in FIG9 ); wherein the first lens group 11 is used to set the parameters (e.g., numerical aperture, field of view, etc.) of the imaging mechanism 10, which determines the basic performance of the imaging mechanism 10; the second lens group 12 is arranged coaxially between the first lens group 11 and the third lens group 13 to achieve aberration correction, mainly spherical aberration, coma, and chromatic aberration; the third lens group 13 is used to achieve finite conjugate distance imaging and can also be used to correct field curvature; and the fourth lens group 14 is used to achieve image telecentricity, thereby ensuring the imaging effect of the imaging mechanism 10. Image telecentricity can further ensure image clarity during long-distance transmission, thereby reducing light loss in long-distance transmission.

[0107] It should be noted that image-side telecentricity means that the chief ray of each off-axis field of view is parallel to the optical axis (or approximately parallel to the optical axis), and image-side non-telecentricity means that the chief ray of each off-axis field of view is not parallel to the optical axis. The chief ray is generally located at the center of the diffuse spot of the corresponding field of view on the image side. When it is located on the image plane, the diffuse spot is smallest, and the diffuse spot gradually becomes larger after the image plane. For a telecentric system, the height and angle of the chief ray remain unchanged after the image plane. For a non-telecentric system, the height of the chief ray increases and the angle remains unchanged. For the subsequent receiving system, the receiving system diameter and deflection angle required by the telecentric system are much lower than those of the non-telecentric system. It can be seen that image-side telecentricity can ensure that the image clarity remains unchanged under long-distance transmission.

[0108] The first lens group 11 includes a second lens 112 disposed along the optical axis A and having a flat surface facing the object side. The surface of the second lens 112 facing the image side is convex. Light reflected from the surface of a biological object sequentially passes through the flat and convex surfaces formed on the object and image sides of the second lens 112, respectively, to converge the reflected light. This effectively prevents light loss caused by the reflected light not being able to pass through the second lens group 12 due to its large reflection angle. The surface of the second lens 112 facing the object side can be either convex or flat, and is preferably flat. This prevents or reduces the accumulation of liquid or other debris on this surface (i.e., the surface of the second lens 112 facing the object side) when the imaging mechanism 10 is mounted on an optical inspection device.

[0109] The first lens group 11 further includes a third lens 113 disposed on the image side of the second lens 112 along the optical axis. The image-facing surface of the third lens 113 is convex. Light reflected from the object surface is refracted through the second lens 112 to form refracted light. The third lens 113 is disposed on the image side of the second lens 112 to re-converge the refracted light from the second lens 112. This further prevents light loss caused by the refracted light not being able to pass through the second lens group 12 due to a large refraction angle (i.e., the refraction angle formed by the optical axis A). Among them, the surface of the third lens 113 facing the object side forms a convex surface or a flat surface. When the surface of the third lens 113 facing the object side forms a convex surface, the refracted light is converged twice by the convex surface (i.e., the surface of the third lens 113 facing the object side), and the refracted light is converged thrice by the convex surface of the third lens 113 facing the image side, thereby further preventing the problem of light loss caused by the refracted light having a large refraction angle and being unable to pass through the second lens group 12; when the surface of the third lens 113 facing the object side forms a flat surface, the flat surface (i.e., the surface of the third lens 113 facing the object side) does not converge the refracted light, and the refracted light is only converged twice by the convex surface of the third lens 113 facing the image side, thereby preventing the problem of light loss caused by the refracted light having a large refraction angle and being unable to pass through the second lens group 12. Whether the surface of the third lens 113 facing the object side is a convex surface or a flat surface, it is sufficient as long as the third lens 113 can converge the refracted light formed by the second lens 112.

[0110] The first lens group 11 also includes a first lens 111 disposed on the object side of the second lens 112 with its plane facing the object side, coaxially with the first lens 111. The first lens 111 is disposed on the object side of the second lens 112, that is, the first lens 111 is disposed closest to the object side of the imaging mechanism 10 to shield the second lens 112, the third lens 113, and the second lens group 12, thereby preventing wear on the object-facing surface of the second lens 112. Furthermore, the first lens 111 is configured as a plane mirror to avoid light loss caused by the reflected light passing through the first lens 111, which would result in partial or complete failure of the refracted light to pass through the second lens 112. This reduces interference of the first lens 111 with the reflected light path. In practical applications, the first lens 111 can also be filled with saline.

[0111] It should be noted that the first lens group 11 can be formed by the second lens 112 alone, or by the second lens 112 and the third lens 113 in combination, or by the first lens 111 and the second lens 112 in combination, or by the first lens 111, the second lens 112, and the third lens 113 in combination. This embodiment does not specifically limit the combination of the first lens group 11, and any of the above situations can be used, as long as the first lens group 11 can converge reflected light from the surface of the biological body to set parameter data of the imaging mechanism 10, such as numerical aperture and field of view. Preferably, the first lens group 11 is formed by the first lens 111, the second lens 112, and the third lens 113 in combination, with the first lens 111 being a plane mirror, the second lens 112 being a plano-convex lens, and the third lens 113 being a biconvex lens.

[0112] The second lens 112 and the third lens 113 included in the first lens group 11, the second lens group 12, the third lens group 13, and the fourth lens group 14 are coaxially arranged within the imaging lens sheath 101. Furthermore, a plurality of second isolation rings 110 are axially abutted between the first lens group 11, the second lens group 12, the third lens group 13, and the fourth lens group 14. The second isolation rings 110 are used to secure the positions of the first lens group 11, the second lens group 12, the third lens group 13, and the fourth lens group 14 and stabilize their axial distances.

[0113] The outer mirror sheath 42 extends axially over the imaging mirror sheath object side end 1012 to form a protective end 421. The first lens 111 contained in the first lens group 11 is coaxially arranged in the protective end 421. It should be noted that, with respect to the arrangement of the first lens 111 and the second lens 112, the first lens 111 and the second lens 112 can be arranged in a joined manner (as shown in FIG7 ), or the first lens 111 and the second lens 112 can be arranged axially spaced apart (as shown in FIG8 ). In this embodiment, it is preferred that the first lens 111 and the second lens 112 are joined in a joined manner (as shown in FIG7 ), and the first lens 111 forms a plane on both the object side and the image side. The joined arrangement means that the surface of the first lens 111 facing the image side is aligned with the surface of the second lens 112 facing the image side. The surfaces facing the object side are attached to each other and formed into one surface, so as to eliminate the refractive loss of the two surfaces (i.e., the surface of the first lens 111 facing the image side and the surface of the second lens 112 facing the object side) and prevent total refraction in the gap. At the same time, it is convenient to shield and prevent dust from the optical elements such as the second lens group 12 and the third lens group 13, thereby avoiding the wear of the surface of the second lens 112 facing the object side. Optionally, the gap between the first lens 111 and the second lens 112 can be vacuumed to reduce the interference of air on the refracted light.

[0114] The second lens group 12 includes a fourth lens 121, convexly facing the object side, and a fifth lens 122, convexly facing the image side, arranged from the object side and joined together along the optical axis A. The fourth lens 121 has a convex surface facing the object side and a concave surface facing the image side, while the fifth lens 122 has convex surfaces facing both the image side and the object side. Refracted light from the first lens group 11 sequentially passes through the fourth lens 121 and the fifth lens 122. The fourth lens 121 diverges the refracted light from the first lens group 11, while the fifth lens 122 converges the refracted light from the fourth lens 121, thereby correcting spherical aberration, coma, and chromatic aberration.

[0115] The fourth lens 121 and the fifth lens 122 can be arranged in a joined configuration as described above, i.e., the image-facing surface of the fourth lens 121 and the object-facing surface of the fifth lens 122 are bonded together to form a second lens group 12 with overall positive power. This eliminates refractive losses on two surfaces (i.e., the image-facing surface of the fourth lens 121 and the object-facing surface of the fifth lens 122) and prevents total refraction due to the gap. This also facilitates the assembly of the fourth lens 121 and the fifth lens 122. Of course, the gap between the fourth lens 121 and the fifth lens 122 can also be evacuated as described above to reduce interference with refracted light.

[0116] The third lens group 13 includes: a sixth lens 131 arranged coaxially with the optical axis A. The surface of the sixth lens 131 facing the object side forms a convex surface, and the surface of the sixth lens 131 facing the image side forms a concave surface. The convex surface converges the refracted light from the second lens group 12 (or the first lens group 11) and the concave surface diverges the refracted light from the convex surface, so as to achieve finite conjugate distance imaging and correct field curvature (i.e., image field curvature).

[0117] The fourth lens group 14 includes a seventh lens 141 and an eighth lens 142, arranged sequentially from the object side along the optical axis A. The seventh lens 141 has a concave surface facing the object side and a convex surface facing the image side, while the eighth lens 142 has a convex surface facing the object side and a concave surface facing the image side. The concave surface of the seventh lens 141 diverges the refracted light transmitted from the third lens group 13, while the convex surface of the seventh lens 141 converges the refracted light. The convex surface of the eighth lens 142 converges the refracted light transmitted from the seventh lens 141, while the concave surface of the eighth lens 142 diverges the refracted light, thereby achieving image-side telecentricity.

[0118] It should be noted that, as shown in Figure 9, in the present application, the imaging mechanism 10 can be composed of a first lens group 11, a second lens group 12, a third lens group 13 and a fourth lens group 14. The parameter data of the imaging mechanism 10 (for example, numerical aperture, field of view, etc.) is controlled by the first lens group 11 to determine the basic performance of the imaging mechanism 10; the aberration correction is achieved by the second lens group 12, and the correction of spherical aberration, coma and chromatic aberration is mainly achieved; the finite conjugate distance imaging is achieved by the third lens group 13, and the field curvature is corrected at the same time; the image telecentricity is achieved by the fourth lens group 14, thereby ensuring the imaging effect of the imaging mechanism 10, and the image telecentricity can further ensure the clarity of the image under long-distance transmission, so as to reduce the light loss existing in long-distance transmission.

[0119] In this embodiment, each optical element satisfies the following conditions: the combined focal length f1 of the first lens group 11 and the conjugate distance T (i.e., the conjugate distance T of the imaging mechanism 10) satisfy 0.15≤f1 / T≤0.18, the combined focal length f1 of the first lens group 11 and the combined focal length f2 of the second lens group 12 satisfy 7≤f2 / f1≤11.5, the combined focal length f2 of the second lens group 12 and the combined focal length f3 of the third lens group 13 satisfy 2.2≤f2 / f3≤4.5, the combined focal length f4 of the fourth lens group 14 and the combined focal length f1 of the first lens group 11 satisfy 1.8≤f4 / f1≤2.2, and the focal length f1 of the seventh lens 141 satisfies 41 The focal length f of the eighth lens 142 is 42 Satisfy -1≤f 42 / f 41 ≤-0.8, the curvature radius r3 of the surface of the second lens 112 facing the image side is equal to the focal length f of the second lens 11212 Satisfying -0.91≤r3 / f 12 ≤-0.81, the curvature radius r9 of the convex surface of the sixth lens 131 facing the object side and the combined focal length f3 of the third lens group 13 satisfy 0.15≤r9 / f3≤0.35, and the curvature radius r9 of the convex surface of the seventh lens 141 facing the image side 12 The curvature radius r corresponding to the convex surface of the eighth lens 142 facing the object side is 13 Satisfying -0.7≤r 12 / r 13 ≤-0.5, the center thickness D9 of the sixth lens 131 and the conjugate distance T satisfy 0.13≤D9 / T. If the object-facing surface of the third lens 113 is convex, the curvature radius r4 of the object-facing surface of the third lens 113, the working distance H of the imaging mechanism 10, and the air gap H1 between the second lens 112 and the third lens 113 satisfy 4.75≤r4 / (H+H1)≤15.9. The air gap H1 refers to the distance between the center of the second lens 112 and the center of the third lens 113, and the working distance H refers to the distance between the center of the object-facing surface of the second lens 112 and the biological subject.

[0120] [Example 1]

[0121] The lens structure diagram of the imaging mechanism 10 of the first embodiment is shown in FIG9 . The diagramming method is as described above, and repeated description is omitted here.

[0122] The imaging mechanism 10 of the first embodiment is constructed by arranging a first lens group 11 with positive refractive power, a second lens group 12 with positive refractive power, a third lens group 13 with positive refractive power, and a fourth lens group 14 with positive refractive power, sequentially from the object side, along the optical axis (i.e., optical axis A). The first lens group 11 is composed, in order from the object side, of a second lens 112 with a flat surface facing the object side and a third lens 113 with a convex surface facing the image side. The first lens 111 is omitted, and before imaging, the surface of the second lens 112 facing the object side is immersed in saline solution to form a layer of saline solution. The second lens group 12 is composed, in order from the object side, of a fourth lens 121 with a convex surface facing the object side and a fifth lens 122 with a convex surface facing the image side. The third lens group 13 is composed of a sixth lens 131 with a convex surface facing the object side. The fourth lens group 14 is composed, in order from the object side, of a seventh lens 141 with a concave surface facing the object side and an eighth lens 142 with a convex surface facing the object side. The second lens 112 to the eighth lens 142 are all spherical lenses.

[0123] Table 1 shows the basic parameters of the optical elements included in the imaging mechanism 10 of the first embodiment, and includes the serial number (i), the radius of curvature (r i )、Center thickness (D i ), refractive index (Ndi ) and the Abbe number (vd j The optical elements refer to the aforementioned saline solution and the second lens 112 to the eighth lens 142. The column of serial number (i) in the basic parameter table indicates that the surface of the optical element closest to the object side is the first surface and the number of the i-th (i=1, 2, 3, ...) surface increases in sequence toward the image side, and the two surfaces of the two optical elements joined are defined as one surface (for example, the fourth lens 121 and the fifth lens 122 are joined, and the surface of the fourth lens 121 facing the image side and the surface of the fifth lens 122 facing the object side are defined as one surface), and the surface of the saline solution facing the image side and the surface of the second lens 112 facing the object side are defined as one surface, and the radius of curvature (r i ) column represents the curvature radius of the i-th surface, and the curvature radius (r i ) is positive when the surface is convex toward the object side and negative when it is convex toward the image side. i ) column, D1 represents the distance between the center of the first surface and the center of the second surface (i.e., the center thickness of the saline solution), D2 represents the distance between the center of the second surface and the center of the third surface (i.e., the center thickness of the second lens 112), D3 represents the distance between the center of the third surface and the center of the fourth surface (i.e., the air gap between the second lens 112 and the third lens 113), and so on. 13 The distance between the center of the 13th face and the center of the 14th face, D 14 Indicates the distance between the center of the 14th plane and the image plane of the biological body. i ) column represents the refractive index between the i-th surface and the i+1-th surface, Nd1 represents the refractive index between the 1st surface and the 2nd surface (i.e., the refractive index of saline), Nd2 represents the refractive index between the 2nd surface and the 3rd surface (i.e., the refractive index of the second lens 112), Nd3 represents the refractive index between the 3rd surface and the 4th surface (i.e., the refractive index of the air between the second lens 112 and the third lens 113), and so on. Abbe number (vd j ) represents the Abbe number of the j-th (j=1, 2, 3, ...) optical element, and the Abbe number is recorded at the serial number corresponding to the surface of the optical element facing the object side.

[0124] It should be noted that the specific meaning of i mentioned above is defined in sequence from the object side to the image side, and the surface of the physiological saline facing the object side is defined as the first surface (i.e., i=1); since the physiological saline is bonded to the second lens 112, the surface of the physiological saline facing the image side is bonded to the surface of the second lens 112 facing the object side, and therefore the two surfaces (i.e., the surface of the physiological saline facing the image side and the surface of the second lens 112 facing the object side) are defined as the same surface, i.e., the second surface (i.e., i=2); the surface of the second lens 112 facing the image side is defined as the third surface (i.e., i=3); the surface of the third lens 113 facing the object side is defined as the fourth surface (i.e., i=4)... and so on. The specific meaning of j is defined in sequence from the object side to the image side. The physiological saline is defined as the first optical element (i.e., j=1), and the Abbe number corresponding to the first optical element is filled in the column corresponding to the surface of the physiological saline facing the object side (i.e., i=1); the second lens 112 is defined as the second optical element (i.e., j=2), and the Abbe number corresponding to the second optical element is filled in the column corresponding to the surface of the second lens 112 facing the object side (i.e., i=2); the third lens 113 is defined as the third optical element (i.e., j=3), and the Abbe number corresponding to the third optical element is filled in the column corresponding to the surface of the third lens 113 facing the object side (i.e., i=4), and so on.

[0125] In Example 1, the numerical aperture (NA) of the imaging mechanism 10 is 0.5, the object-side field of view is 0.5 (unit, millimeters, mm), the image-side telecentricity is less than 0.2 (unit, degrees, °), and the working distance is 0.5 (unit, millimeters, mm). "Millimeter" (abbreviated as "mm") is used as the unit of length for the numerical values ​​in Table 1. However, this is only one column and can be scaled up or down. Therefore, other appropriate units may also be used. Table 1 also shows values ​​rounded to the specified number of digits.

[0126] Table 1

[0127] Table 2 shows the calculated values ​​of the various optical elements of Example 1

[0128] Table 2

[0129] Referring to FIG. 10 , FIG. 10 shows an MTF curve of the imaging mechanism 10 of the first embodiment under a field of view of 1.0.

[0130] The horizontal axis in FIG10 represents the spatial frequency (cycles / mm). The spatial frequency in FIG10 ranges from 0 to 620, and is spaced at intervals of 5 cycles / mm. The actual values ​​(i.e., the vertical axis values) corresponding to the Y axis of line type 3 (tangential transfer function) are: 1, 0.988823, 0.977607, 0.966306, 0.954857, 0.943218, and 0.931446, respectively. , 0.919606, 0.907723, 0.895815, 0.883894, 0.871974, 0.860067, 0.848184, 0.836321, 0.824479, 0.812669, 0.800896, 0.789156, 0.77745, 0.765788, 0.754175, 0.742606, 0.731084, 0.719625, 0.708231, .696881, 0.685578, 0.674352, 0.66327, 0.652425, 0.641792, 0.631215, 0.620642, 0.610128, 0.599697, 0.589337, 0.579027, 0.568738, 0.558492, 0.54835, 0.538362, 0.528566, 0.518897, 0.509231, 0.4 99553, 0.489911, 0.480318, 0.470768, 0.461231, 0.451676, 0.442163, 0.43278, 0.423547, 0.414444, 0.405416, 0.3964, 0.38737, 0.378332, 0.369378, 0.360603, 0.351959, 0.34338, 0.334903, 0.326574, 0.318381, 0.310292, 0.302268, 0.294265, 0.286253, 0.278243, 0.270358, 0.262673, 0.255074, 0.247489, 0.240026, 0.232737, 0.225502, 0.218265, 0.211146, 0.204185 , 0.197247, 0.190284, 0.183432, 0.176724, 0.170008, 0.16325, 0.156603, 0.15009, 0.143546, 0.136956, 0.130489, 0.124154, 0.117776, 0.111362, 0.10511, 0.098996, 0.0.92797, 0.086605, 0.080767, 0.075238, 0.069677, 0.064096, 0.058738, 0.053541, 0.048263, 0.043071, 0.038322, 0.033842, 0.029222, 0.024744, 0.020941, 0.017522, 0.013924, 0.010467, 0.007711, 0.005253, 0.002545, 0.000453, 0.000004, 0.000351, 0.000301, 0.000007, 0.0, 0. The actual values ​​of the Y-axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.988892, 0.977776, 0.966632, 0.955391, 0.943999, 0.932501, 0.920949, 0.909359, 0.89774, 0.886098, 0.874441, 0.862781, 0.851126, 0.839473, 0.827823, 0.816189 , 0.804579, 0.792988, 0.781421, 0.769889, 0.7584, 0.74695, 0.735542, 0.724192, 0.712904, 0.701665, 0.69047, 0.679338, 0.668337, 0.657586, 0.647066, 0.636607, 0.626152, 0.615757, 0.605446, 0.595206, 0.585021, 0.574 866, 0.564755, 0.554727, 0.544852, 0.535206, 0.525717, 0.516236, 0.506742, 0.497288, 0.487889, 0.478535, 0.469196, 0.459846, 0.450529, 0.441313, 0.432249, 0.423361, 0.414568, 0.405764, 0.396927, 0.388072, 0.3792 77, 0.370615, 0.362081, 0.35365, 0.345304, 0.33704, 0.328896, 0.320893, 0.312944, 0.304961, 0.29692, 0.288844, 0.280846, 0.272999, 0.265232, 0.257493, 0.249839, 0.242297, 0.234805, 0.227333, 0.219948, 0.212671, 0.20542, 0.198171, 0.191011, 0.183959, 0.176913, 0.169856, 0.162897, 0.156051, 0.149196, 0.142326, 0.135575, 0.128947, 0.122296, 0.115638, 0.109149, 0.102796, 0.096362, 0.089939, 0.08387, 0.078134, 0.072435, 0.0 66767, 0.06132, 0.056009, 0.050597, 0.045268, 0.040416, 0.035845, 0.031107, 0.026501, 0.022598, 0.019086, 0.015367, 0.011811, 0.009039, 0.00653, 0.003578, 0.001092, 0.000225, 0.000296, 0.000237, 0.000044, 0, 0.

[0131] Referring to FIG. 11 , FIG. 11 shows an MTF curve of the imaging mechanism 10 of the first embodiment at a field of view of 0.707.

[0132] The horizontal axis in Figure 11 represents the spatial frequency, with the unit being cycles / mm. The spatial frequency in Figure 11 ranges from 0 to 620, with an interval of 5 cycles / mm. The actual values ​​of line type 3 (tangential transfer function) corresponding to the Y axis (i.e., the vertical axis) are: 1, 0.989015, 0.978098, 0.967277, 0.956424, 0.945424, 0.934297, 0.923081, 0.911776, and 0. 900377, 0.888896, 0.877344, 0.865731, 0.854066, 0.842361, 0.830629, 0.818881, 0.80713, 0.795387, 0.783664, 0.771972, 0.760321, 0.748716, 0.737167, 0.725687, 0.714278, 0.702931, 0.691646, 0.680437, 0.669372, 0.65856 8, 0.648003, 0.637504, 0.627013, 0.616586, 0.606244, 0.595972, 0.585747, 0.575546, 0.565382, 0.555294, 0.545349, 0.535616, 0.526023, 0.51642, 0.506787, 0.497179, 0.487608, 0.478064, 0.468516, 0.45894, 0.449381, 0.4 39914, 0.430587, 0.421417, 0.412327, 0.403218, 0.394067, 0.384893, 0.375777, 0.366803, 0.35796, 0.349213, 0.340559, 0.332008, 0.323591, 0.315322, 0.307123, 0.298915, 0.290673, 0.282421, 0.27428, 0.266331, 0.258489, 0.250699, 0.243031, 0.235523, 0.228095, 0.220712, 0.213455, 0.206351, 0.199302, 0.192273, 0.185369, 0.178609, 0.171874, 0.165136, 0.15852, 0.152038, 0.14555, 0.13904, 0.132657, 0.126401, 0.120105, 0.113779, 0.107612, 0.101567, 0..095406, 0.089223, 0.08338, 0.077847, 0.072297, 0.066729, 0.061362, 0.056111, 0.050721, 0.045387, 0.040522, 0.035928, 0.031142, 0.026477, 0.022532, 0.018989, 0.015224, 0.011625, 0.008835, 0.006328, 0.003389, 0.000947, 0.00017, 0.000314, 0.000246, 0.000014, 0. The actual values ​​of the Y-axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.989055, 0.978203, 0.967487, 0.956783, 0.94597, 0.935068, 0.924118, 0.913114, 0.90205, 0.890932, 0.879768, 0.868562, 0.857319, 0.846047, 0.834752, 0.823443, 0 .812128, 0.800814, 0.789508, 0.778221, 0.766957, 0.755722, 0.744522, 0.733366, 0.722259, 0.711192, 0.700164, 0.68918, 0.678309, 0.667677, 0.657267, 0.646901, 0.636521, 0.626185, 0.615915, 0.605695, 0.595507, 0.585 333, 0.575183, 0.565086, 0.555115, 0.545355, 0.535737, 0.526103, 0.516434, 0.506785, 0.497172, 0.487581, 0.477989, 0.468372, 0.458768, 0.449241, 0.439848, 0.430628, 0.421495, 0.412337, 0.403138, 0.393921, 0.38475 2. 0.375702, 0.366779, 0.357972, 0.349252, 0.340603, 0.332081, 0.32372, 0.315428, 0.307109, 0.298748, 0.290373, 0.282086, 0.273958, 0.265936, 0.257981, 0.250127, 0.242395, 0.234743, 0.227156, 0.219673, 0.212307, 0.205003, 0.197743, 0.190586, 0.183545, 0.176543, 0.169565, 0.162692, 0.155932, 0.149188, 0.142453, 0.135832, 0.129324, 0.122807, 0.116293, 0.109928, 0.103678, 0.09735, 0.091027, 0.085015, 0.079301, 0.07363, 0.0679 92, 0.062542, 0.057196, 0.051746, 0.04637, 0.041437, 0.036768, 0.031952, 0.027269, 0.023257, 0.019631, 0.01584, 0.012236, 0.009398, 0.006825, 0.003843, 0.001308, 0.000313, 0.00027, 0.000219, 0.000081, 0.000012, 0. .

[0133] Referring to FIG. 12 , FIG. 12 shows an MTF curve diagram of the imaging mechanism 10 of the first embodiment under the central field of view.

[0134] The horizontal axis in FIG12 is the spatial frequency (Spatial Frequency), and the unit is cycles per millimeter (cycles / mm). The spatial frequency in FIG12 ranges from 0 to 620, and is spaced at intervals of 5 cycles per millimeter. The actual values ​​(i.e., the vertical axis values) corresponding to the Y axis of line type 3 (tangential transfer function) are: 1, 0.989061, 0.978207, 0.967478, 0.956748, 0.945899, 0.934956, 0.923957, 0.912905, 0.901796, 0.890642, and 0.8 79456, 0.868245, 0.857018, 0.845786, 0.834559, 0.823345, 0.812153, 0.800991, 0.789866, 0.778784, 0.767751, 0.756767, 0.745838, 0.734969, 0.72416, 0.713403, 0.70269, 0.692023, 0.681463, 0.671142, 0.661037, 0.650971, 0.640879, 0.630819, .620809, 0.610832, 0.60087, 0.590906, 0.580945, 0.571011, 0.561178, 0.551539, 0.542024, 0.532471, 0.522859, 0.513247, 0.503648, 0.494048, 0.484425, 0.47476, 0.465085, 0.455456, 0.44594, 0.436582, 0.427297, 0.417967, 0.408576, 0.399155 , 0.389762, 0.380459, 0.371271, 0.362198, 0.3532, 0.34425, 0.335415, 0.326747, 0.318146, 0.309511, 0.300834, 0.292147, 0.283545, 0.275093, 0.266761, 0.25852, 0.250387, 0.242373, 0.234463, 0.226652, 0.218957, 0.211385, 0.203905, 0.19651, 0.189235, 0.182083, 0.175007, 0.167997, 0.161106, 0.154336, 0.147619, 0.140948, 0.134397, 0.127963, 0.121549, 0.115167, 0.108928, 0.1028, 0..096616, 0.090448, 0.08456, 0.078949, 0.073404, 0.067907, 0.062568, 0.057307, 0.051946, 0.046654, 0.04176, 0.037108, 0.03233, 0.02768, 0.023647, 0.019979, 0.016188, 0.012594, 0.009717, 0.007094, 0.004106, 0.001539, 0.000411, 0.000243, 0.000196, 0.000118, 0.000052, 0. The actual values ​​of the Y-axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.989061, 0.978207, 0.967478, 0.956748, 0.945899, 0.934956, 0.923957, 0.912905, 0.901796, 0.890642, 0.879456, 0.868245, 0.857018, 0.845786, 0.834559, 0.82334 5. 0.812153, 0.800991, 0.789866, 0.778784, 0.767751, 0.756767, 0.745838, 0.734969, 0.72416, 0.713403, 0.70269, 0.692023, 0.681463, 0.671142, 0.661037, 0.650971, 0.640879, 0.630819, 0.620809, 0.610832, 0.60087, 0. 590906, 0.580945, 0.571011, 0.561178, 0.551539, 0.542024, 0.532471, 0.522859, 0.513247, 0.503648, 0.494048, 0.484425, 0.47476, 0.465085, 0.455456, 0.44594, 0.436582, 0.427297, 0.417967, 0.408576, 0.399155, 0.389 762, 0.380459, 0.371271, 0.362198, 0.3532, 0.34425, 0.335415, 0.326747, 0.318146, 0.309511, 0.300834, 0.292147, 0.283545, 0.275093, 0.266761, 0.25852, 0.250387, 0.242373, 0.234463, 0.226652, 0.218957, 0.211385, 0.203905, 0.19651, 0.189235, 0.182083, 0.175007, 0.167997, 0.161106, 0.154336, 0.147619, 0.140948, 0.134397, 0.127963, 0.121549, 0.115167, 0.108928, 0.1028, 0.096616, 0.090448, 0.08456, 0.078949, 0.073404, 0.06790 7, 0.062568, 0.057307, 0.051946, 0.046654, 0.04176, 0.037108, 0.03233, 0.02768, 0.023647, 0.019979, 0.016188, 0.012594, 0.009717, 0.007094, 0.004106, 0.001539, 0.000411, 0.000243, 0.000196, 0.000118, 0.000052, 0. .

[0135] It should be noted that line type 1 in Figures 10 to 12 represents the diffraction-limited transfer function in the meridional direction, line type 2 represents the diffraction-limited transfer function in the sagittal direction, line type 3 represents the actual transfer function in the meridional direction, and line type 4 represents the actual transfer function in the sagittal direction.

[0136] As shown in Figures 10 through 12, under ideal conditions, the coincidence of the meridional transfer function (i.e., Line Type 1) and the sagittal transfer function (i.e., Line Type 2) achieves optimal imaging with low distortion. In actual testing, the closer the ordinate values ​​of Line Type 3 and Line Type 4, corresponding to the same abscissa value, are, the closer the actual meridional transfer function and sagittal transfer function are. This is particularly evident in the MTF curve at the center field of view shown in Figure 12. Furthermore, from an actual imaging perspective, the closer the ordinate values ​​of Line Type 3 and Line Type 4, corresponding to the same abscissa value, are to those of Line Type 1 and Line Type 2, respectively, the better the imaging quality, the more realistic the image, and the lower the distortion.

[0137] 13 shows the Siemens Star chart of the imaging mechanism 10 of Example 1. As shown in FIG13 , the Siemens Star chart corresponding to the imaging mechanism 10 is clear. The better the resolution and the higher the contrast, the clearer the image.

[0138] Unless otherwise specified, the above-mentioned diagrammatic representation method, symbols, meanings, and recording methods of the imaging mechanism 10 of the first embodiment are also applicable to the imaging mechanism 10 of the following embodiments, and therefore repeated descriptions are omitted below.

[0139] [Example 2]

[0140] The optical element structure diagram of the imaging mechanism 10 of the second embodiment is shown in FIG9 , which is the same structure as the imaging mechanism 10 of the first embodiment. The diagramming method is as described above, and repeated description is omitted here. Table 3 shows the basic parameters of the optical elements included in the imaging mechanism 10 of the second embodiment, including the serial number (i), the radius of curvature (r i )、Center thickness (D i ), refractive index (Nd i ) and the Abbe number (vd j ).

[0141] In the second embodiment, the numerical aperture (NA) of the imaging mechanism 10 is 0.5, the object-side field of view is 0.5 mm, the image-side telecentricity is less than 0.2 degrees, and the working distance is 1.989 mm.

[0142] Table 3

[0143] Table 4 shows the calculated values ​​of the optical elements of Example 2

[0144] Table 4

[0145] 14 to 16 , which are MTF curves of the imaging mechanism 10 at 0.707 field of view, 1.0 field of view, and center field of view, respectively. Referring to FIG17 , FIG17 shows a Siemens star chart of the imaging mechanism 10 in Example 2.

[0146] The horizontal axis in FIG14 represents the spatial frequency (cycles / mm). The spatial frequency in FIG14 ranges from 0 to 620, and is spaced at intervals of 5 cycles / mm. The actual values ​​(i.e., the vertical axis values) corresponding to the Y axis of line type 3 (tangential transfer function) are: 1, 0.988939, 0.977875, 0.966782, 0.955542, 0.944059, 0.932363, 0.920499, 0.908478, 0.896309, 0.884016, 0.871623, 0.859148, 0.846613, 0.834041, 0.821455, 0.808877, 0.796328, 0.78383, 0.771402, 0.759065, 0.746835, 0.734722, 0.722741, 0.710908, 0.69 9228, 0.687692, 0.676296, 0.665056, 0.654033, 0.643341, 0.632952, 0.622689, 0.612485, 0.602388, 0.592413, 0.582536, 0.572729, 0.562959, 0.55323, 0.543577, 0.534058, 0.524736, 0.515537, 0.506303, 0.497011, 0.487711, 0.478415, 0.469107, 0.45976, 0.450345, 0.440908, 0.431524, 0.422243, 0.413085, 0.403976, 0.394819, 0.385596, 0.376328, 0.367101, 0.358001, 0.349023, 0.340142, 0.331355, 0.322675, 0.314142, 0.305774, 0.297498, 0.289237, 0.280972, 0.272728, 0.26463, 0.2567 58, 0.249032, 0.241399, 0.233928, 0.226652, 0.219496, 0.212423, 0.205509, 0.198775, 0.192125, 0.185522, 0.17906, 0.172753, 0.166481, 0.160213, 0.154062, 0.148036, 0.141993, 0.135916, 0.129941, 0.124066, 0.118124, 0.112126, 0.106253, 0.0.019036, 0.015272, 0.011673, 0.008881, 0.00637, 0.003427, 0.000975, 0.00018, 0.000311, 0.000245, 0.00002, 0.019036, 0.015272, 0.011673, 0.008881, 0.00637, 0.003427, 0.000975, 0.00018, 0.000311, 0.000245, 0.00002, 0.019036, 0.015272 The actual values ​​of the Y-axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.989007, 0.978053, 0.967146, 0.956168, 0.945015, 0.933717, 0.922315, 0.910813, 0.899211, 0.887519, 0.875753, 0.863924, 0.852043, 0.840126, 0.828188, 0.8162 45, 0.804313, 0.792409, 0.780547, 0.768743, 0.757012, 0.745361, 0.733801, 0.722346, 0.711, 0.699758, 0.688615, 0.677573, 0.666697, 0.656114, 0.645803, 0.635582, 0.625387, 0.615267, 0.605239, 0.595282, 0.585374, 0 .575492, 0.565637, 0.55583, 0.54614, 0.536657, 0.527309, 0.517931, 0.5085, 0.499071, 0.489657, 0.480243, 0.470808, 0.46133, 0.451842, 0.4424, 0.433072, 0.423906, 0.414817, 0.405687, 0.396504, 0.387299, 0.378131 , 0.369063, 0.360122, 0.351313, 0.342595, 0.333938, 0.325416, 0.31708, 0.308831, 0.300568, 0.292282, 0.284007, 0.275833, 0.267825, 0.259953, 0.252189, 0.244544, 0.237024, 0.229615, 0.222309, 0.21512, 0.208044, 0.201054、0.194138、0.187323、0.180608、0.173945、0.16732、0.160781、0.154326、0.147887、0.141456、0.135104、0.128824、0.122526、0.116222、0.110023、0.103898、0.097689、0.091472、0.08551、0.079806、0.074162、0.068564、0.063121、0.057758、0.052306、0.046935、0.041971、0.03726、0.032442、0.027766、0.02371、0.020027、0.016233、0.012641、0.009761、0.007132、0.004144、0.001574、0.000427、0.000239、0.000192、0.000123、0.000058、0。.

[0147] The horizontal axis in Figure 15 is the spatial frequency (Spatial Frequency), unit: cycles per millimeter (cycles / mm). In Figure 15, the range of spatial frequency is 0 to 620, and the actual values ​​of line type 3 (tangential transfer function) corresponding to the Y axis (i.e., ordinate value) are shown at intervals of 5 cycles per millimeter: 1, 0.988603, 0.976989, 0.964987, 0.952579, 0.939807, 0.92678, 0.91361, 0.900372, 0.887122, 0.873901, 0.860743, 0.847683, 0.834742, 0.821919, 0.809214, 0.796645, 0.784221, 0.77193, 0.759768, 0.747748, 0.735874, 0.724134, 0.712526, 0.701067, 0.689756, 0.678561, 0.667482, 0.656555, 0.645841, 0.635412, 0.62523, 0.615143, 0.605094, 0.595128, 0.585258, 0.575469, 0.565727, 0.555991, 0. 546282, 0.536664, 0.527173, 0.517821, 0.508537, 0.499209, 0.48982, 0.480407, 0.470985, 0.461549, 0.452064, 0.442499, 0.432922, 0.423439, 0.414053, 0.404731, 0.395432, 0.386119, 0.376769, 0.36 7384, 0.358077, 0.348957, 0.339964, 0.331022, 0.322196, 0.313562, 0.30509, 0.296733, 0.288473, 0.280296, 0.27217, 0.264105, 0.25623, 0.248619, 0.241148, 0.233741, 0.226517, 0.219533, 0.212655 , 0.205817, 0.199141, 0.19267, 0.186256, 0.179843, 0.17356, 0.167435, 0.161313, 0.155153, 0.149091, 0.143144, 0.137157, 0.131107, 0.125139, 0.119263, 0.113324, 0.107327, 0.101433, 0.095627, 0.0.089739, 0.083849, 0.078242, 0.072877, 0.067471, 0.062035, 0.056781, 0.051674, 0.046536, 0.041491, 0.03681, 0.032368, 0.027871, 0.023533, 0.019755, 0.016333, 0.012855, 0.009508, 0.006661, 0.004187, 0.001884, 0.000257, 0, 0.000079, 0.000118, 0.000003, 0, 0. The actual values ​​of the Y-axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.988998, 0.977829, 0.966366, 0.954627, 0.942664, 0.930531, 0.918278, 0.905941, 0.893547, 0.881114, 0.86866, 0.856206, 0.843771, 0.831356, 0.818969, 0.806632, 0. 794361, 0.782155, 0.770018, 0.757976, 0.746041, 0.734206, 0.722474, 0.710869, 0.699397, 0.688036, 0.676781, 0.66565, 0.654706, 0.644064, 0.633697, 0.623437, 0.613218, 0.603087, 0.593059, 0.583122, 0.573252, 0.56341 7. 0.553624, 0.543908, 0.534335, 0.524978, 0.515764, 0.50654, 0.497283, 0.488043, 0.478834, 0.469646, 0.460452, 0.451226, 0.442008, 0.432868, 0.423862, 0.415018, 0.406259, 0.397478, 0.388657, 0.379815, 0.371026, 0.3 62368, 0.353843, 0.345435, 0.33712, 0.328893, 0.320801, 0.312875, 0.305024, 0.297159, 0.28926, 0.281353, 0.273544, 0.265906, 0.258376, 0.25091, 0.243548, 0.236312, 0.229149, 0.222036, 0.215021, 0.208115, 0.201249, 0.194399、0.187633、0.180962、0.174296、0.167614、0.161008、0.154485、0.147938、0.141355、0.134857、0.128443、0.121983、0.115492、0.109131、0.102871、0.096514、0.090149、0.084102、0.078362、0.072662、0.066999、0.061543、0.056212、0.050789、0.045458、0.040594、0.036011、0.031281、0.026689、0.022782、0.019261、0.01555、0.012006、0.009227、0.006699、0.003735、0.001219、0.000276、0.00028、0.000227、0.000067、0、0。.

[0148] The horizontal axis in FIG16 represents the spatial frequency (cycles / mm). The spatial frequency in FIG16 ranges from 0 to 620, and is spaced at intervals of 5 cycles / mm. The actual values ​​of line type 3 (tangential transfer function) corresponding to the Y axis (i.e., the vertical axis) are: 1, 0.989048, 0.978154, 0.967336, 0.95647, 0.945441, 0.934274, 0.923009, 0.911646, 0.900187, 0.888646, 0.877041, and 0.8653 84, 0.853691, 0.84198, 0.83027, 0.818577, 0.806917, 0.795307, 0.783762, 0.772296, 0.760919, 0.749638, 0.73846, 0.727395, 0.716444, 0.705601, 0.694856, 0.684203, 0.673702, 0.663485, 0.65353, 0.643652, 0.63378, 0.623966, 0.614222, 0.604527, 0.594858, 0.585196, 0.575537, 0.565895, 0.556341, 0.546975, 0.537727, 0.528426, 0.519049, 0.509652, 0.500247, 0.490817, 0.481345, 0.471813, 0.462246, 0.4526 9. 0.44322, 0.433901, 0.424643, 0.415317, 0.405916, 0.396477, 0.387048, 0.377679, 0.368416, 0.359283, 0.350221, 0.341184, 0.332262, 0.323527, 0.314 872, 0.306183, 0.297467, 0.288761, 0.280143, 0.271671, 0.263346, 0.255156, 0.247087, 0.239132, 0.231312, 0.223639, 0.216093, 0.208663, 0.201356, 0. 194178, 0.187118, 0.18017, 0.173321, 0.166569, 0.159922, 0.153371, 0.146887, 0.140466, 0.134135, 0.127882, 0.121658, 0.115469, 0.10938, 0.10336, 0.0.097293, 0.091239, 0.085397, 0.079783, 0.074266, 0.06882, 0.063486, 0.058196, 0.052834, 0.047545, 0.042597, 0.037871, 0.033081, 0.028434, 0.024319, 0.02055, 0.016749, 0.013169, 0.010216, 0.007502, 0.004522, 0.00193, 0.000589, 0.000201, 0.000154, 0.000171, 0.000115, 0. The actual values ​​of the Y-axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.989048, 0.978154, 0.967336, 0.95647, 0.945441, 0.934274, 0.923009, 0.911646, 0.900187, 0.888646, 0.877041, 0.865384, 0.853691, 0.84198, 0.83027, 0.818577 , 0.806917, 0.795307, 0.783762, 0.772296, 0.760919, 0.749638, 0.73846, 0.727395, 0.716444, 0.705601, 0.694856, 0.684203, 0.673702, 0.663485, 0.65353, 0.643652, 0.63378, 0.623966, 0.614222, 0.604527, 0.594858, .585196, 0.575537, 0.565895, 0.556341, 0.546975, 0.537727, 0.528426, 0.519049, 0.509652, 0.500247, 0.490817, 0.481345, 0.471813, 0.462246, 0.45269, 0.44322, 0.433901, 0.424643, 0.415317, 0.405916, 0.396477, 0. 387048, 0.377679, 0.368416, 0.359283, 0.350221, 0.341184, 0.332262, 0.323527, 0.314872, 0.306183, 0.297467, 0.288761, 0.280143, 0.271671, 0.263346, 0.255156, 0.247087, 0.239132, 0.231312, 0.223639, 0.216093, 0.208663, 0.201356, 0.194178, 0.187118, 0.18017, 0.173321, 0.166569, 0.159922, 0.153371, 0.146887, 0.140466, 0.134135, 0.127882, 0.121658, 0.115469, 0.10938, 0.10336, 0.097293, 0.091239, 0.085397, 0.079783, 0.074266, 0. 0.06882, 0.063486, 0.058196, 0.052834, 0.047545, 0.042597, 0.037871, 0.033081, 0.028434, 0.024319, 0.02055, 0.016749, 0.013169, 0.010216, 0.007502, 0.004522, 0.00193, 0.000589, 0.000201, 0.000154, 0.000171, 0.000115, 0. .

[0149] It should be noted that in Figures 14 to 16, line type 1 represents the meridional diffraction-limited transfer function, line type 2 represents the sagittal diffraction-limited transfer function, line type 3 represents the actual meridional transfer function, and line type 4 represents the actual sagittal transfer function. As shown in Figures 14 to 16, under ideal conditions, the coincidence of the meridional transfer function (i.e., line type 1) and the sagittal transfer function (i.e., line type 2) achieves optimal imaging with low distortion. In actual testing, the closer the ordinate values ​​of line type 3 and line type 4, corresponding to the same abscissa value, are, the closer the actual meridional transfer function and the actual sagittal transfer function are. Furthermore, from an actual imaging perspective, the closer the ordinate values ​​of line type 3 and line type 4, corresponding to the same abscissa value, are to the ordinate values ​​of line type 1 and line type 2, respectively, the better the imaging quality, the more realistic the image, and the lower the image distortion.

[0150] [Example 3]

[0151] The optical element structure diagram of the imaging mechanism 10 of the second embodiment is shown in FIG9 , which has the same structure as the imaging mechanism 10 of the first embodiment. The diagramming method is as described above, and repeated description is omitted here. Table 5 shows the basic parameters of the optical elements included in the imaging mechanism 10 of the third embodiment, including the serial number (i), the radius of curvature (r i )、Center thickness (D i ), refractive index (Nd i ) and the Abbe number (vd j ).

[0152] In the third embodiment, the numerical aperture (NA) of the imaging mechanism 10 is 0.5, the object-side field of view is 0.5 mm, the image-side telecentricity is less than 0.2 degrees, and the working distance is 2.15 mm.

[0153] Table 5

[0154] Table 6 shows the calculated values ​​of the optical elements of Example 3

[0155] Table 6

[0156] Referring to Figures 18 to 20, Figure 18 shows an MTF curve of the imaging mechanism 10 of Example 3 at a field of view of 0.707, Figure 19 shows an MTF curve of the imaging mechanism 10 of Example 3 at a field of view of 1.0, and Figure 20 shows an MTF curve of the imaging mechanism 10 of Example 3 at a center field of view. Referring to Figure 21, Figure 21 shows a Siemens Star chart of the imaging mechanism 10 of Example 3.

[0157] The horizontal axis in FIG18 represents the spatial frequency (Spatial Frequency), and the unit is cycles / mm. The spatial frequency in FIG18 ranges from 0 to 630, and is spaced at intervals of 5 cycles / mm. The actual values ​​(i.e., the vertical axis values) corresponding to the Y axis of line type 3 (tangential transfer function) are: 1, 0.988963, 0.977883, 0.966706, 0.955349, 0.943742, 0.931908, 0.919885, 0.907686, 0.895322, 0.882814, 0.870187, 0.857467, 0.84468, 0.831857, 0.81903, 0.806228, 0.79348, 0.780815, 0.768257, 0.755832, 0.743558, 0.731448, 0.719512, 0.707768, 0.696227, 0.684867, 0.67367, 0.662667, 0.651902, 0.641439, 0.631304, 0.6213 73, 0.611517, 0.601746, 0.592091, 0.582544, 0.57308, 0.56365, 0.554225, 0.544861, 0.535626, 0.526532, 0.517561, 0.508615, 0.499606, 0.490544, 0.481463, 0.472368, 0.463248, 0.454058, 0.444777, 0.435507, 0.426349, 0. 417277, 0.408235, 0.399186, 0.390098, 0.380939, 0.371711, 0.362552, 0.353578, 0.344694, 0.335798, 0.326987, 0.318367, 0.309883, 0.301457, 0.29308, 0.284754, 0.27644, 0.268129, 0.259978, 0.252115, 0.244399, 0.23669 5, 0.229145, 0.221891, 0.214786, 0.207682, 0.200725, 0.194057, 0.187521, 0.18096, 0.174518, 0.168339, 0.162261, 0.156118, 0.150056, 0.144217, 0.138439, 0.132559, 0.126717, 0.121058, 0.115426, 0.109668, 0.103922, 0.0.098328, 0.092733, 0.087008, 0.081407, 0.076157, 0.071015, 0.065714, 0.0604, 0.055249, 0.050164, 0.045054, 0.040099, 0.035468, 0.031004, 0.026564, 0.022389, 0.018708, 0.015309, 0.011967, 0.008822, 0.006049, 0.003586, 0.001439, 0.000128, 0.000016, 0.000327, 0.000253, 0, 0, 0. The actual values ​​of the Y-axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.989022, 0.978051, 0.967072, 0.95598, 0.944679, 0.933192, 0.921562, 0.909799, 0.897907, 0.885903, 0.873806, 0.861638, 0.849417, 0.837167, 0.824912, 0.8126 76, 0.800482, 0.788352, 0.776305, 0.764361, 0.752536, 0.740839, 0.729278, 0.717869, 0.706623, 0.695516, 0.684529, 0.673697, 0.663074, 0.652716, 0.642648, 0.632748, 0.622893, 0.613095, 0.603387, 0.593764, 0.5842 0.4, 0.574659, 0.565098, 0.55559, 0.546212, 0.53697, 0.527837, 0.518724, 0.509548, 0.50032, 0.491073, 0.481814, 0.472539, 0.463194, 0.453755, 0.444339, 0.435062, 0.425882, 0.416725, 0.407564, 0.398374, 0.389114, 0.379778, 0.37052, 0.361471, 0.352513, 0.343527, 0.334626, 0.325934, 0.317379, 0.30886, 0.300376, 0.291935, 0.283492, 0.275033, 0.266726, 0.258712, 0.250833, 0.242934, 0.235178, 0.227723, 0.220404, 0.213061, 0.205852、0.198935、0.192143、0.185306、0.178581、0.172123、0.165763、0.159332、0.152979、0.146855、0.140797、0.134643、0.128532、0.122609、0.116728、0.110738、0.104768、0.098947、0.093146、0.087259、0.081519、0.076132、0.070869、0.065482、0.060083、0.054827、0.049666、0.044546、0.039581、0.034884、0.03038、0.025999、0.021882、0.018162、0.014744、0.011506、0.008443、0.005603、0.003121、0.001184、0.000109、0.000037、0.000297、0.000223、0、0、0。.

[0158] The horizontal axis in FIG19 is the spatial frequency (Spatial Frequency), and the unit is cycles per millimeter (cycles / mm). The spatial frequency in FIG19 ranges from 0 to 630, and is spaced at intervals of 5 cycles per millimeter. The actual values ​​(i.e., the vertical axis values) corresponding to the Y axis of line type 3 (tangential transfer function) are: 1, 0.988465, 0.976517, 0.963856, 0.950633, 0.937084, 0.923348, 0.909535, and 0.8 95737, 0.882026, 0.868414, 0.854905, 0.841532, 0.828323, 0.81526, 0.802326, 0.789544, 0.776935, 0.764486, 0.752181, 0.740037, 0.728071, 0.716272, 0.704626, 0.693147, 0.681845, 0.670704, 0.659704, 0.648844, 0.638148, 0.627713, 0.617606, 0.607693, 0.597833, 0.588033, 0.578331, 0.568715, 0.55916, 0.549642, 0.54014, 0.530662, 0.521237, 0.511941, 0.502822, 0.493757, 0.484618, 0 .475428, 0.466233, 0.457032, 0.447812, 0.438555, 0.429253, 0.419949, 0.410699, 0.401565, 0.392582, 0.383665, 0.374725, 0.365766, 0.356825, 0.347963, 0.339238, 0.330673, 0.322273, 0.31401, 0.305867, 0.297901, 0.290155, 0.282557, 0.275021, 0.267537, 0.260128, 0.252863, 0.245803, 0.238922, 0.232183, 0.225591, 0.219155, 0.212851, 0.206656, 0.200576, 0.194612, 0.188731, 0.1829, 0.177131, 0.171434, 0.165765, 0.160082, 0.154408, 0.148766, 0.143106, 0.137382, 0.131635, 0.125903, 0.120135, 0.114283, 0.10842, 0.102611, 0.096771, 0.090839, 0.084982, 0.079362, 0.073886, 0.068442, 0.0631, 0.057933, 0.05283, 0.047711, 0.042805, 0.038303, 0.033948, 0.02951 3. 0.025351, 0.02178, 0.018416, 0.014893, 0.011644, 0.009056, 0.006541, 0.003624, 0.001249, 0.000333, 0.000256, 0.000202, 0.000099, 0.000034, 0. The actual values ​​of the Y axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.988684, 0.977182, 0.965353, 0.953247, 0.940955, 0.928565, 0.916153, 0.903772, 0.891459, 0.879214, 0.867038, 0.854949, 0.842964, 0.831066, 0.819236, and 0.8 0.7491, 0.79585, 0.784299, 0.772822, 0.761436, 0.750161, 0.738983, 0.72789, 0.716902, 0.706037, 0.695264, 0.684559, 0.673956, 0.663508, 0.653283, 0.643316, 0.63349, 0.623681, 0.613903, 0.604194, 0.594553, 0.5 84964, 0.575387, 0.565795, 0.556248, 0.546817, 0.537531, 0.528384, 0.519278, 0.510119, 0.500925, 0.491735, 0.482556, 0.473379, 0.464161, 0.454883, 0.445644, 0.436543, 0.427568, 0.418677, 0.409817, 0.400937, 0.39201, 0.383044, 0.374166, 0.365483, 0.356914, 0.348367, 0.339913, 0.331632, 0.323487, 0.315416, 0.307383, 0.29936, 0.291306, 0.28322, 0.275248, 0.26751, 0.25987, 0.252195, 0.244616, 0.237258, 0.229982, 0.222647、0.215391、0.208349、0.201368、0.194297、0.187284、0.180476、0.173709、0.166824、0.15998、0.153335、0.146721、0.139975、0.133264、0.12676、0.120294、0.113703、0.107166、0.100859、0.0946、0.088231、0.082061、0.076374、0.070891、0.06531、0.059799、0.054557、0.049437、0.044302、0.039385、0.034897、0.030593、0.026251、0.022187、0.0187、0.015471、0.012174、0.009059、0.006402、0.003981、0.001662、0.000148、0、0.00035、0.000276、0、0、0。.

[0159] The horizontal axis in FIG20 is the spatial frequency (Spatial Frequency), and the unit is cycles per millimeter (cycles / mm). The spatial frequency in FIG20 ranges from 0 to 630, and the actual values ​​(i.e., the vertical axis values) corresponding to the Y axis of line type 3 (tangential transfer function) are shown at intervals of 5 cycles per millimeter: 1, 0.989005, 0.977998, 0.966945, 0.95574, 0.944284, 0.932604, 0.920747, 0.908728, 0.896555, 0.884257, 0.871864, 0.859404, 0.846903, 0.834392, 0.821903, 0.809462, and 0. .797097, 0.78483, 0.772684, 0.760678, 0.748828, 0.73714, 0.72562, 0.714283, 0.703137, 0.692154, 0.68131, 0.670642, 0.6602, 0.650036, 0.640168, 0.6 30473, 0.620829, 0.611243, 0.601747, 0.592334, 0.582981, 0.573637, 0.564269, 0.554947, 0.545751, 0.536681, 0.527705, 0.518734, 0.509688, 0.500578, 0.491433, 0.482263, 0.47306, 0.463771, 0.454371, 0.44498, 0.435715, 0.426527, 0.417341, 0.40813, 0.398874, 0.389531, 0.380094, 0.37072, 0.361544, 0.352442, 0.343289, 0.334209, 0.325334, 0.316585, 0.307854, 0.299148, 0.290483, 0.281816, 0.273132, .264605, 0.256377, 0.24829, 0.240189, 0.232242, 0.224612, 0.217136, 0.20965, 0.202316, 0.195298, 0.188427, 0.181535, 0.174777, 0.168309, 0.161965, 0.155578, 0.149291, 0.143252, 0.137301, 0.131281, 0.125321, 0.119557, 0.11385, 0.108056, 0.102286, 0.0.96656, 0.091054, 0.085385, 0.079857, 0.074655, 0.069565, 0.064351, 0.059108, 0.053974, 0.048926, 0.043929, 0.039067, 0.034423, 0.029964 , 0.025662, 0.021608, 0.017894, 0.01448, 0.011296, 0.008276, 0.005411, 0.002924, 0.001084, 0.000112, 0.000051, 0.000281, 0.000207, 0, 0, 0. The actual values ​​of the Y-axis (i.e., the ordinate values) corresponding to line type 4 (actual transfer function in the sagittal direction) are: 1, 0.989005, 0.977998, 0.966945, 0.95574, 0.944284, 0.932604, 0.920747, 0.908728, 0.896555, 0.884257, 0.871864, 0.859404, 0.846903, 0.834392, 0.821903, and 0.809 462, 0.797097, 0.78483, 0.772684, 0.760678, 0.748828, 0.73714, 0.72562, 0.714283, 0.703137, 0.692154, 0.68131, 0.670642, 0.6602, 0.650036, 0.640168, 0.630473, 0.620829, 0.611243, 0.601747, 0.592334, 0.582981, 0.573637, 0.564269, 0.554947, 0.545751, 0.536681, 0.527705, 0.518734, 0.509688, 0.500578, 0.491433, 0.482263, 0.47306, 0.463771, 0.454371, 0.44498, 0.435715, 0.426527, 0.417341, 0.40813, 0.398874, 0.389531, .380094, 0.37072, 0.361544, 0.352442, 0.343289, 0.334209, 0.325334, 0.316585, 0.307854, 0.299148, 0.290483, 0.281816, 0.273132, 0.264605, 0.256377, 0.24829, 0.240189, 0.232242, 0.224612, 0.217136, 0.20965, 0.202316, 0.195298, 0.188427, 0.181535, 0.174777, 0.168309, 0.161965, 0.155578, 0.149291, 0.143252, 0.137301, 0.131281, 0.125321, 0.119557, 0.11385, 0.108056, 0.102286, 0.096656, 0.091054, 0.085385, 0.079857, 0.074655, 0.06 9565, 0.064351, 0.059108, 0.053974, 0.048926, 0.043929, 0.039067, 0.034423, 0.029964, 0.025662, 0.021608, 0.017894, 0.01448, 0.011296, 0.008276, 0.005411, 0.002924, 0.001084, 0.000112, 0.000051, 0.000281, 0.000207, 0, 0, 0.

[0160] It should be noted that in Figures 18 to 20, line type 1 represents the meridional diffraction-limited transfer function, line type 2 represents the sagittal diffraction-limited transfer function, line type 3 represents the actual meridional transfer function, and line type 4 represents the actual sagittal transfer function. As shown in Figures 18 to 20, under ideal conditions, the overlap of the meridional transfer function (i.e., line type 1) and the sagittal transfer function (i.e., line type 2) achieves optimal imaging with low distortion. In actual testing, the closer the ordinate values ​​of line type 3 and line type 4, corresponding to the same abscissa value, are, the closer the actual meridional transfer function and the actual sagittal transfer function are. Furthermore, from an actual imaging perspective, the closer the ordinate values ​​of line type 3 and line type 4, corresponding to the same abscissa value, are to the ordinate values ​​of line type 1 and line type 2, respectively, the better the imaging quality, the more realistic the image, and the lower the image distortion.

[0161] As shown in Figures 2 and 6, the coaxial optical system 100 further includes a mirror base 50, which is disposed at the image-side end 423 of the outer mirror sheath and forms a removable adapter 43 with the mirror base 50. The outer mirror sheath 42 is mounted on the mirror base 50 via the adapter 43 and is removably connected to the mirror base 50 via the adapter 43. The removable connection between the adapter 43 and the mirror base 50 can be achieved by, but is not limited to, a snap-fit ​​connection, threads, or screws.

[0162] As shown in Figure 6, the mirror base 50 is constructed with a receiving channel 51 that accommodates at least a portion of the image-transmitting mirror sheath 301. The receiving channel 51 forms a stepped recess 52 radially inwardly, which serves as an axial abutment for the image-side end 3013 of the image-transmitting mirror sheath. The inner mirror sheath 41 axially penetrates the adapter 43 and extends into the mirror base 50, abutting against the stepped recess 52 formed by the mirror base 50. The inner mirror sheath 41 is axially abutted between the mirror base 50 and the outer abutment 21. By accommodating at least a portion of the image-transmitting mirror sheath 301 and the inner mirror sheath 41 through the receiving channel 51, the rod-shaped mirror assemblies 311 within the image-transmitting mirror sheath 301 are aligned, improving the coaxiality between the rod-shaped mirror assemblies 311. The longer the axial length of the receiving channel 51, the higher the coaxiality between the rod-shaped mirror assemblies 311. The inner mirror sheath 41 is axially abutted between the mirror base 50 and the outer abutment 21, improving the stability of its installation.

[0163] Based on the technical solutions of any of the above-mentioned coaxial optical systems 100 disclosed in the aforementioned embodiments and their reasonable combinations, this embodiment further discloses an endoscopic imaging system 200 .

[0164] The endoscopic imaging system 200 includes a mirror base 50 having a dichroic mirror 70, a light source 60, and a coaxial optical system 100 as disclosed in the above-described embodiment. The mirror base 50 included in the coaxial optical system 100 is configured to receive incident light from the light source 60 incident on the dichroic mirror 70. After being reflected by the dichroic mirror 70, the coaxial optical system 100 captures reflected light from the object W to be measured (including a living organism or ex vivo biological tissue). The reflected light passes through the dichroic mirror 70 and is captured by the endoscopic imaging system 200.

[0165] The mirror base 50 is provided with a receiving light source 60 that is incident on the dichroic mirror 70 along the direction indicated by the arrow R1 in FIG. 3 . The light is then reflected by the dichroic mirror 70 along the direction indicated by the arrow R2 in FIG. 3 and sequentially enters the image relay mechanism 30 and the imaging mechanism 10 included in the coaxial optical system 100 . The light is then converged on the object W to be measured by the imaging mechanism 10 . The tissue surface of the object W to be measured forms a reflection of the light. The imaging mechanism 10 collects the reflected light emitted by the object W to be measured and forms an image. The image formed by the imaging mechanism 10 is then proportionally transmitted through the image relay mechanism 30 . The reflected light passes through the dichroic mirror 70 along the direction indicated by the arrow R3 in FIG. 3 to be captured by the endoscopic imaging system 200 , and then provided to an operator (e.g., a medical staff or a scientific researcher) to observe the image of the organism.

[0166] Based on the endoscopic imaging system 200 disclosed in the aforementioned embodiment, this embodiment further discloses an application of the endoscopic imaging system. The endoscopic imaging system 200 disclosed in the aforementioned embodiment is used to perform optical imaging of biological tissue (including living or ex vivo biological tissue), thereby allowing an operator (e.g., a medical professional or a scientific researcher) to observe the biological image. The details are described above and will not be repeated here.

[0167] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

[0168] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0169] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. An endoscope coaxial holding system, characterized in that: include: An image-transmitting mirror sheath, a connecting piece and an imaging mirror sheath are arranged in sequence on the same optical axis from the image side; The image-transmitting mirror sheath and the imaging mirror sheath have the same optical axis, and the image-transmitting mirror sheath and the imaging mirror sheath are respectively supported against the radial outer wall and the radial inner wall of the connecting member in the axial direction; The image-relay mirror sheath is coaxially and radially outwardly provided with an inner mirror sheath and an outer mirror sheath in sequence, and the outer mirror sheath is axially separated from the inner mirror sheath; The outer sheath at least partially extends axially beyond the object side end of the imaging sheath, the outer sheath is radially separated or radially connected to the connector, and a gap is formed between the outer sheath and the inner sheath for axial separation of the outer sheath relative to the inner sheath.

2. The endoscope coaxial holding system according to claim 1, characterized in that: The connecting piece is provided with an outer abutment portion protruding radially outwards for axial abutment of the image transfer mirror sheath, and the connecting piece is provided with a retaining portion concave radially inwards for axial abutment of the imaging mirror sheath and partially extending into the connecting piece; The image-transmitting mirror sheath and the imaging mirror sheath have the same optical axis, which is formed by the image-transmitting mirror sheath and the imaging mirror sheath respectively abutting against the outer abutting portion and the retaining portion in opposite directions along the axial direction.

3. The endoscope coaxial holding system according to claim 2, characterized in that: The outer mirror sheath is at least partially radially separated from the outer abutment portion; The at least partial radial separation of the outer mirror sheath and the outer abutment portion is formed by at least partial clearance fit or interference fit between the outer mirror sheath and the outer abutment portion, so that the outer mirror sheath can be axially separated relative to the outer abutment portion.

4. The endoscope coaxial holding system according to claim 2, characterized in that: The outer mirror sheath is radially connected to at least a portion of the outer abutment portion; The outer mirror sheath is fixedly connected to at least a portion of the outer abutting portion, so that the outer mirror sheath drives the connecting member to axially separate relative to the image relay mirror sheath.

5. The endoscope coaxial holding system according to claim 1, characterized in that: A clearance fit or an interference fit is formed between the image-relay mirror sheath and the inner mirror sheath.

6. The endoscope coaxial holding system according to claim 2, characterized in that: A first abutting surface formed by the image relay mirror sheath axially abutting against the outer abutting portion and a second abutting surface formed by the imaging mirror sheath axially abutting against the retaining portion are axially spaced apart or located in the same radial plane of the optical axis.

7. An endoscope coaxial optical system, characterized in that: include: An image transfer mechanism, a connecting piece and an imaging mechanism are arranged in sequence on the same optical axis from the image side; The image transfer mechanism and the imaging mechanism have the same optical axis, which is formed by the image transfer mirror sheath contained in the image transfer mechanism and the imaging mirror sheath contained in the imaging mechanism being axially opposed to each other and respectively abutting against the radial outer wall and the radial inner wall of the connecting member; The image-relay mirror sheath is coaxially and radially outwardly provided with an inner mirror sheath and an outer mirror sheath in sequence, and the outer mirror sheath is axially separated from the inner mirror sheath; The outer mirror sheath at least partially extends axially beyond the object side end of the imaging mirror sheath, and the outer mirror sheath is radially separated or radially connected to the connecting piece.

8. The endoscope coaxial optical system according to claim 7, characterized in that: A gap is formed between the outer mirror sheath and the inner mirror sheath for axially separating the outer mirror sheath from the inner mirror sheath.

9. The endoscope coaxial optical system according to claim 7, characterized in that: The connecting piece is provided with an outer abutment portion protruding radially outwards for axial abutment of the image transfer mirror sheath, and the connecting piece is provided with a retaining portion concave radially inwards for axial abutment of the imaging mirror sheath and partially extending into the connecting piece; The image-transmitting mirror sheath and the imaging mirror sheath have the same optical axis, which is formed by the image-transmitting mirror sheath and the imaging mirror sheath respectively abutting against the outer abutting portion and the retaining portion in opposite directions along the axial direction.

10. The endoscope coaxial optical system according to claim 9, characterized in that: The outer mirror sheath is at least partially radially separated from the outer abutment portion; The at least partial radial separation of the outer mirror sheath and the outer abutment portion is formed by at least partial clearance fit or interference fit between the outer mirror sheath and the outer abutment portion, so that the outer mirror sheath can be axially separated relative to the outer abutment portion.

11. The endoscope coaxial optical system according to claim 9, characterized in that: The outer mirror sheath is radially connected to at least a portion of the outer abutment portion; The outer mirror sheath is fixedly connected to at least a portion of the outer abutting portion, so that the outer mirror sheath drives the connecting member to axially separate relative to the image relay mirror sheath.

12. The endoscope coaxial optical system according to claim 9, characterized in that: A first abutting surface formed by the image relay mirror sheath axially abutting against the outer abutting portion and a second abutting surface formed by the imaging mirror sheath axially abutting against the retaining portion are axially spaced apart or located in the same radial plane of the optical axis.

13. The endoscope coaxial optical system according to claim 11, characterized in that: The image transfer mechanism comprises: an odd number of image transfer mirror groups greater than or equal to three arranged in the image transfer mirror sheath at intervals along the same optical axis, and a plurality of first isolation rings axially supported between adjacent image transfer mirror groups; The image-transmitting mirror group is symmetrically composed of two rod-shaped mirror groups.

14. The endoscope coaxial optical system according to claim 13, characterized in that: The outer abutment portion forms a limiting end that at least partially axially extends into the image-transmitting mirror sheath, and the limiting end axially abuts against the rod-shaped lens group inside the object-side end of the image-transmitting mirror sheath.

15. The endoscope coaxial optical system according to claim 14, characterized in that: At least one annular groove is formed in the circumference of the limiting end, and a filling layer is embedded in the annular groove to prevent the image relay sheath from being axially separated from the connecting piece.

16. The endoscope coaxial optical system according to claim 15, characterized in that: The filling layer is an adhesive medium or a sealing medium.

17. The endoscope coaxial optical system according to claim 9, characterized in that: The connecting piece is constructed with an axially arranged connecting channel, the imaging mirror sheath portion is accommodated in the connecting channel, and the connecting channel is radially protruded inward to form the retaining portion for axially supporting the imaging mirror sheath.

18. The endoscope coaxial optical system according to claim 14, characterized in that: A clearance fit or an interference fit is formed between the image-relay mirror sheath and the inner mirror sheath.

19. The endoscope coaxial optical system according to claim 14, characterized in that: The imaging mechanism comprises: a first lens group with positive optical power, a second lens group with positive optical power, a third lens group with positive optical power and a fourth lens group with positive optical power are arranged in sequence on the same optical axis from the object side; The first lens group includes a second lens with a flat surface facing the object side, the second lens group includes a fourth lens with a convex surface facing the object side and a fifth lens with a convex surface facing the image side, the third lens group includes a sixth lens with a convex surface facing the object side and a concave surface facing the image side, the fourth lens group includes a seventh lens with a concave surface facing the object side and a convex surface facing the image side, and an eighth lens with a convex surface facing the object side and a concave surface facing the image side; The combined focal length f1 of the first lens group and the conjugate distance T satisfy 0.15≤f1 / T≤0.18, the combined focal length f4 of the fourth lens group and the combined focal length f1 of the first lens group satisfy 1.8≤f4 / f1≤2.2, and the focal length f of the seventh lens 41 The focal length f of the eighth lens 42 Satisfies -1≤f 42 / f 41 ≤-0.

8.

20. The endoscope coaxial optical system according to claim 19, characterized in that: The first lens group further includes: a third lens having the same optical axis as that disposed on the image side of the second lens; The surface of the third lens facing the image side is formed into a convex surface.

21. The endoscope coaxial optical system according to claim 19, characterized in that: The first lens group further includes: a first lens which is arranged on the object side of the second lens with the same optical axis and whose plane faces the object side.

22. The endoscope coaxial optical system according to claim 21, characterized in that: The outer mirror sheath axially extends over the object side end of the imaging mirror sheath to form a protection end, and the first lens is coaxially arranged in the protection end.

23. The endoscope coaxial optical system according to any one of claims 9 to 22, characterized in that: The endoscope coaxial optical system also includes: The mirror seat is arranged at the image side end of the outer mirror sheath and forms a detachable adapter seat with the mirror seat.

24. The endoscope coaxial optical system according to claim 23, characterized in that: The mirror seat is configured to form an accommodating channel for accommodating at least a portion of the image relay mirror sheath, and the accommodating channel forms a stepped recess radially inwardly for the image side end of the image relay mirror sheath to axially abut.

25. The endoscope coaxial optical system according to claim 24, characterized in that: The inner mirror sheath axially penetrates the adapter seat and extends into the mirror base to abut against the step recess formed by the mirror base. The inner mirror sheath is axially abutted between the mirror base and the outer abutting portion.

26. An endoscopic imaging system, characterized in that: include: A mirror holder with a dichroic mirror, a light source, and an endoscopic coaxial optical system as described in any one of claims 7 to 25; the mirror holder contained in the endoscopic coaxial optical system is arranged to receive incident light from the light source incident on the dichroic mirror, and reflected light formed from the object to be measured is captured by the endoscopic coaxial optical system after being reflected by the dichroic mirror, and the reflected light passes through the dichroic mirror to be captured by the endoscopic imaging system.

27. Application of an endoscopic imaging system, characterized in that: The endoscopic imaging system according to claim 26 is used to perform optical imaging of biological tissue.

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