Endoscope, endoscope assembly and operating microscope system

Abstract

The invention provides an endoscope, an endoscope assembly and an operating microscope system. The light beams collected by two or more than two light receiving modules from different angles of an observation target are combined into coaxially propagating light beams through a beam combining module; and an image sensor is arranged at the image space after beam combination to image the light beams collected from different angles of the observation target, so that the three-dimensional image information of the observation target of the endoscope is obtained. According to the scheme, through the arrangement of the beam combining module, dual-optical-path imaging is changed into single-optical-path imaging, and part of optical paths are reduced, so that the number of optical elements is reduced, the cost of the endoscope is reduced, and the microminiaturization of the endoscope is realized; according to the three-dimensional amplitude calibration, only the optical elements need to physically change the light propagation path, a complex 3D image processing algorithm is not needed, the number of the optical elements needing to be precisely assembled and calibrated can be reduced, and therefore the imaging complexity can be reduced.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to an endoscope, an endoscope assembly, and a surgical microscope system. Background Technology

[0002] In the fields of medical and precision testing, 3D endoscopes, with their stereoscopic vision imaging capabilities, can provide richer spatial depth information, significantly improving the accuracy of observation and operation, and have important application value in scenarios such as minimally invasive surgery and internal structure inspection.

[0003] Currently, 3D endoscopes are implemented in the following ways: Figure 1 As shown, a dual-path optical imaging system is set up to observe the target from the left and right perspectives. The dual-path optical imaging system adopts a physically separated independent optical path design. Each beam imaging system includes an imaging lens group and an image sensor. Beams from different angles of the observed target enter the dual-path beam imaging system "parallel". The dual-path optical imaging system synchronously acquires left and right perspective images with a fixed baseline offset (about 5mm). In addition to time alignment, the back-end processor also needs to crop and stitch the images acquired by the two image sensors. Complex pixel-level spatial alignment and color calibration are required during stitching to obtain the 3D video stream image.

[0004] Although this solution can provide high-quality stereoscopic images, it has significant drawbacks: 1. The dual-path optical imaging system uses a physically separate design, which makes it difficult to miniaturize the endoscope due to its large diameter; 2. Each path in the dual-path optical imaging system requires a separate imaging lens group and image sensor, resulting in a large number of components and high costs; 3. The images obtained by the dual-path optical imaging system need to be cropped and stitched together, requiring complex pixel-level spatial alignment and color calibration, resulting in high algorithm complexity; 4. The optical components of each path in the dual-path optical imaging system require precise assembly and calibration, which involves a large workload. Summary of the Invention

[0005] The purpose of this application is to provide an endoscope, endoscope assembly, and surgical microscope system to solve the above-mentioned problems.

[0006] The first aspect of this application provides an endoscope, comprising: two or more light-collecting modules for collecting light beams from different angles of an endoscope-observed target; a beam-combining module including an optical element having a semi-transparent and semi-reflective surface; the beam-combining module being used to combine the light beams of the observed target collected by each light-collecting module into a coaxially propagating light beam through the semi-transparent and semi-reflective surface; and an image sensor for imaging the light beams collected by the light-collecting modules from different angles of the observed target, thereby obtaining stereoscopic image information of the endoscope-observed target.

[0007] In some embodiments, the beam combining module further includes a reflector and / or a prism, which adjusts the beams of light collected by different light-collecting modules from the endoscopic observation target onto the semi-transparent and semi-reflective surface by combining the positions of the reflector and / or prism with the semi-transparent and semi-reflective surface.

[0008] In some embodiments, the beam combining module includes a first surface, a second surface, a third surface, and a fourth surface; wherein the first surface, the second surface, and the third surface are total reflection surfaces, and the fourth surface is a semi-transparent and semi-reflective surface; the first surface and the third surface are used to reflect the light beams of the observation target collected from different angles; the first surface is used to reflect the light beams of the observation target to the second surface, and the second surface is used to reflect the light beams to the fourth surface so that the light beams are transmitted out from the fourth surface; the third surface is used to reflect the light beams of the observation target to the fourth surface, and the fourth surface reflects the light beams out, and the reflected light beams of the fourth surface coincide with the transmitted light beams.

[0009] In some embodiments, the angle difference between the first surface and the second surface, and the angle difference between the third surface and the fourth surface are equal.

[0010] In some embodiments, the values ​​of the two angle differences are determined based on the ratio of the dual-optical-path spacing length to the calibration distance, wherein the dual-optical-path spacing length is half the distance between the centers of the front ends of the two light-receiving modules, and the calibration distance is the distance between the line connecting the centers of the front ends of the two light-receiving modules and the observed target.

[0011] In some embodiments, the beam combining module includes multiple prisms arranged in a gapless manner within the objective lens tube; a semi-transparent and semi-reflective coating is coated on the contact surface of at least one pair of adjacent prisms; the semi-transparent and semi-reflective coating is used to combine the beams of the observed target collected from different angles by each light receiving module into a coaxially propagating beam.

[0012] In some embodiments, the beam combining module includes a first prism, a second prism, a third prism, and a fourth prism; the second prism and the third prism are located in the middle region of the objective lens tube cross-section and are used to collect beams of light from the observed target from different angles, respectively, with the second prism disposed adjacent to the third prism; the second prism and the third prism have a first adjacent surface and a second adjacent surface, wherein the first adjacent surface is a total reflection surface and the second adjacent surface is a semi-transparent and semi-reflective surface; the adjacent surface of the first prism and the second prism reflects the beam of light from the observed target collected by the second prism to the first adjacent surface, and the first adjacent surface then reflects the beam of light to the second adjacent surface, and the beam of light is transmitted out from the second adjacent surface; the adjacent surface of the third prism and the fourth prism reflects the beam of light from the observed target collected by the third prism to the second adjacent surface, and the second adjacent surface reflects the beam of light out, with the reflected beam of light from the second adjacent surface being parallel to the projected beam.

[0013] In some embodiments, the endoscope further includes a liquid lens disposed on the light propagation path between the beam combining module and the image sensor, wherein the focal length of the liquid lens is dynamically changed by adjusting the liquid state in the liquid lens.

[0014] In some embodiments, the image sensor includes a white light image sensor for white light imaging and a fluorescence sensor for fluorescence imaging; correspondingly, the endoscope further includes a beam splitter disposed on the light propagation path between the beam combining module and the image sensor; the beam splitter is used to separate the propagation directions of white light and fluorescence in the beam combining, the separated white light is incident on the white light sensor, and the separated fluorescence is incident on the fluorescence sensor.

[0015] In some embodiments, the endoscope further includes a parallel plate disposed on the light propagation path between the beam combining module and the image sensor, the parallel plate being used to filter out the excitation light of fluorescence.

[0016] In some embodiments, the light-collecting module includes: a front negative lens for focusing light and adjusting the direction of the incident beam and the field of view; and an optical switch disposed at the front end of the front negative lens for controlling whether the light-collecting module collects the beam of light from the endoscope's observation target.

[0017] A second aspect of this application provides an endoscope assembly including the bundle-combining module of the endoscope described in any one of the first aspects.

[0018] A third aspect of this application provides a surgical microscope system, comprising: an endoscope as described in any one of the first aspects; and an image processing device for processing stereoscopic image information of the target observed by the endoscope.

[0019] The endoscope, endoscope assembly, and surgical microscope system provided in this application combine light beams collected from different angles of the observed target by two or more light-collecting modules into a coaxially propagating beam through a beam-combining module. An image sensor is placed on the image side of the combined beam to image the light beams collected from different angles of the observed target, thereby obtaining a stereoscopic image of the observed target by the endoscope. This solution, through the beam-combining module, transforms dual-light-path imaging into single-light-path imaging, reducing some optical paths and thus reducing the number of optical components, lowering the cost of the endoscope, and enabling miniaturization of the endoscope. Three-dimensional convergence calibration only requires physically altering the light propagation path of the optical components, eliminating the need for complex 3D image processing algorithms (e.g., cropping, stitching, pixel-level spatial alignment, color calibration), and also reducing the number of optical components requiring precise assembly and calibration, thereby reducing imaging complexity. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram illustrating the principle of an existing endoscope. Figure 2 A schematic diagram illustrating the principle of an endoscope provided in this application; Figure 3 A schematic diagram illustrating the principle of another endoscope provided in this application; Figure 4 A schematic diagram of a beam combining module consisting of four prisms and matched with two light-collecting modules, provided in this application; Figure 5 A schematic diagram of a 3D, 4K white light microscopic endoscope (0°) imaging system; Figure 6 A schematic diagram of a 3D, 4K white light microscopic endoscope (30°) imaging system; Figure 7 MTF curves at 20mm for 3D, 4K white light microendoscopic imaging systems (0° and 30°); Figure 8 MTF curves at 50mm for 3D, 4K white light microendoscopic imaging systems (0° and 30°); Figure 9 MTF curves at 200mm for 3D, 4K white light microscopic endoscope (0° and 30°) imaging systems; Figure 10 A schematic diagram of a 3D, 4K white light-fluorescence endoscopic imaging system (0°); Figure 11 A schematic diagram of a 3D, 4K white light-fluorescence endoscopic imaging system (30°); Figure 12 MTF curves at 20mm for 3D, 4K white light-fluorescence microendoscopy (0° and 30°) imaging systems; Figure 13 MTF curves at 50mm for 3D, 4K white light-fluorescence microendoscopy (0° and 30°) imaging systems; Figure 14 MTF curves at 200 mm for 3D, 4K white light-fluorescence microendoscopy (0° and 30°) imaging systems. Detailed Implementation

[0022] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0023] An endoscope is a precision optical instrument that enters the body through natural cavities or tiny incisions to observe, diagnose, and treat internal structures.

[0024] This application provides an endoscope, such as Figure 2 As shown, the endoscope includes a light-collecting module 10, a beam-combining module 20, and an image sensor 30.

[0025] The light-collecting module 10 includes at least two modules. This application uses an endoscope with two light-collecting modules as an example to illustrate the endoscope provided in this application. Two or more light-collecting modules 10 are used to collect light beams from the endoscope's observation target from different angles. The endoscope's observation target can be target tissue or a fluorescent target. The "light beam of the observation target" can be light reflected from the light source of the endoscope's observation target, light emitted by the endoscope's observation target itself, or fluorescence generated by the endoscope's observation target when excited by an external light source.

[0026] At least two light-receiving modules 10 are located at different positions relative to the observed target. While the positions of the at least two light-receiving modules 10 relative to the observed target can be relatively close and have small differences, there are still some differences. These differences in position ensure that the light beams collected by the "different light-receiving modules 10" from the same point A on the observed target intersect, i.e., converge at point A on the observed target. Since at least two light-receiving modules 10 collect light beams from the observed target from different angles, the final image contains information from different angles, thus giving the image a three-dimensional appearance.

[0027] In existing technologies, such as Figure 1 As shown, in a dual-beam imaging system, the optical axes (i.e., reference axes) of the dual-beam imaging system are parallel. Therefore, each of the two optical imaging systems has a light-receiving module at its front end. However, the target beams received by the two light-receiving modules for imaging are parallel. In contrast, in this application, the target beams received by the two or more light-receiving modules 10 for imaging are not parallel, but intersecting.

[0028] In some embodiments, such as Figure 3As shown, the light-gathering module 10 of the endoscope may include a front negative lens 11, which is a lens combination close to the observation target, used to focus light, adjust the direction of the incident beam, and adjust the field of view.

[0029] The front negative lens 11 directly receives the light beam from the observed target, which expands the system's field of view, effectively compensates for overall aberrations, and shares the optical power after the subsequent beam combining module 20.

[0030] In some embodiments, such as Figure 3 As shown, the light-receiving module 10 of the endoscope may further include an optical switch 12 for controlling whether the light-receiving module 10 collects the light beam of the endoscope's observation target. The optical switch 12 has an on state and an off state. In the on state, the light beam of the endoscope's observation target passes through the optical switch and enters the front negative lens 11; in the off state, the light beam of the endoscope's observation target is blocked and does not enter the front negative lens.

[0031] The optical switch 12 can specifically be a liquid crystal polarization switch. A liquid crystal switch is a miniature optical device that dynamically switches the polarization state of light by controlling the electric field based on the optical properties of liquid crystal materials. By precisely controlling the voltage applied to the liquid crystal cell, the alignment direction of the liquid crystal molecules can be actively and rapidly changed, thereby precisely controlling the state of polarized light passing through the lens (transmission or blocking), achieving a rapid optical switching function.

[0032] The beam combining module 20 includes an optical element with a semi-transparent and semi-reflective surface. The semi-transparent and semi-reflective surface allows some light beams to pass through and some to be reflected, thereby achieving beam splitting, beam combining, or beam redirection. The optical element with the semi-transparent and semi-reflective surface can be, for example, a plane beam splitter, a stereo beam splitter, a polarizing beam splitter, a thin-film beam splitter, an adjustable beam splitter, etc.

[0033] A semi-transparent and semi-reflective surface can be a surface that splits light according to energy or wavelength. Specifically, the semi-transparent and semi-reflective surface in beam combining module 20 can be a surface that splits light according to energy.

[0034] A semi-transparent and semi-reflective surface can allow a specific proportion of light to pass through while reflecting the remaining proportion. Specifically, this proportion can be 50% or close to 50%, so that the optical parameters (such as light intensity, color, etc.) of the observed target at different angles in the final image are relatively balanced.

[0035] The number of semi-transparent and semi-reflective surfaces can be one or more. For example, if there are two light-receiving modules 10, only one semi-transparent and semi-reflective surface can be used; if there are three or more light-receiving modules 10, two or more semi-transparent and semi-reflective surfaces can be used. The optical element with the semi-transparent and semi-reflective surface can also be a semi-transparent and semi-reflective film coated on one surface of a prism, or it can be a plate coated with a semi-transparent and semi-reflective film.

[0036] In some embodiments, the beam combining module further includes a mirror and / or a prism. The beam combining module 20 can be a combination of a mirror and an optical element with a semi-transparent, semi-reflective surface, a combination of a prism and an optical element with a semi-transparent, semi-reflective surface, or a combination of a mirror, a prism, and an optical element with a semi-transparent, semi-reflective surface. The beams collected by different light-receiving modules from the endoscopic target are adjusted to the semi-transparent, semi-reflective surface by the positional combination of the mirror and / or prism with the semi-transparent, semi-reflective surface.

[0037] The beam combiner module 20 is used to combine the beams of light collected by each light receiving module 10 from the observed target into a coaxial beam through a semi-transparent and semi-reflective surface. In other words, the beams of light collected by each light receiving module 10 from the observed target become a parallel beam after passing through the beam combiner module 20.

[0038] Image sensor 30 is positioned on the image side of the combined beam and is used to image the beams collected by the light receiving module 10 from different angles of the observed target, that is, to image the beam emitted from the beam combining module 20, thereby obtaining stereoscopic image information of the target observed by the endoscope. Since the beam emitted from the beam combining module 20 is a parallel beam, positioning image sensor 30 on the propagation path of this parallel beam can achieve better imaging results.

[0039] The endoscope provided in this application combines beams collected from different angles of the observed target by two or more light-collecting modules into a coaxially propagating beam using a beam-combining module. An image sensor is placed on the image side of the combined beam to image the beams collected from different angles of the observed target, thereby obtaining a stereoscopic image of the observed target. This solution, through the beam-combining module, transforms dual-light-path imaging into single-light-path imaging, reducing some optical paths and thus the number of optical components, lowering the cost of the endoscope and enabling miniaturization. Three-dimensional convergence calibration only requires physically altering the light propagation path of the optical components, eliminating the need for complex 3D image processing algorithms (e.g., cropping, stitching, pixel-level spatial alignment, color calibration), and further reducing the number of optical components requiring precise assembly and calibration, thereby reducing imaging complexity.

[0040] The endoscope provided in this application uses a beam combining module to merge the light beams collected from different angles of the observed target into a coaxially propagating beam, thus avoiding the optical axis deviation caused by the independent assembly of objective lenses in current dual-path optical imaging systems. The common optical path design of this solution can ensure that the scaling ratio, distortion characteristics and chromatic aberration performance of the images formed by the light beams collected from different angles of the observed target are strictly synchronized, thus guaranteeing the spatial consistency of stereo image pairs from a physical level.

[0041] In some embodiments, the beam combining module 20 includes a first surface, a second surface, a third surface, and a fourth surface. The first, second, and third surfaces are total reflective surfaces, and the fourth surface is a semi-transparent, semi-reflective surface.

[0042] The first and third surfaces are used to reflect beams of light collected from the observed target from different angles.

[0043] The first surface is used to reflect the light beam from the observed target to the second surface, and the second surface is used to reflect the light beam to the fourth surface so that the light beam is transmitted out from the fourth surface.

[0044] The third surface is used to reflect the beam of light from the observed target to the fourth surface, the fourth surface is used to reflect the beam of light out, and the reflected beam of the fourth surface coincides with the transmitted beam.

[0045] The aforementioned beam combining module 20 can combine the beams of the observed targets collected from different angles through light reflection and transmission. At the same time, hardware-level convergence calibration can be directly achieved by physically adjusting the tilt angle of each surface, so that the beams of the observed targets collected from different angles naturally overlap on the image plane (i.e., the image sensor), thus preserving the integrity of the original image information to the greatest extent.

[0046] Figure 4 This is a schematic diagram of a beam combining module 20 consisting of four prisms and matched with two light receiving modules. The beam combining module 20 includes a first prism B1, a second prism B2, a third prism B3, and a fourth prism B4. The first prism B1 and the second prism B2 are arranged adjacent to each other, the second prism B2 and the third prism B3 are arranged adjacent to each other, and the third prism B3 and the fourth prism B4 are arranged adjacent to each other.

[0047] The second prism B2 and the third prism B3 are located in the middle region of the objective lens tube 40 section and are used to collect the beam of light from the observed target from different angles. The second prism B2 is positioned adjacent to the third prism B3. The second prism B2 and the third prism have a first adjacent surface S3 and a second adjacent surface S4, wherein the first adjacent surface S3 is a total reflection surface and the second adjacent surface S4 is a semi-transparent and semi-reflective surface.

[0048] The light beam collected by the light receiving module is incident from the surface S1 of the second prism B2. The beam is reflected from the adjacent surface S2 of the first prism B1 and the second prism B2 to the first adjacent surface S3, then reflected from the first adjacent surface S3 to the second adjacent surface S4, and then transmitted from the second adjacent surface S4 into the third prism B3, and exiting from the surface S7 of the third prism B3.

[0049] Another light-collecting module collects the beam of light from the object under test, which is incident from surface S5 of the third prism B3, then reflected by the adjacent surface S6 of the third prism B3 and the fourth prism B4 to the second adjacent surface S4, and then reflected by the second adjacent surface S4. The reflected light exits from surface S7 of the third prism B3. The light reflected from the second adjacent surface S4 is parallel to the light transmitted from the second adjacent surface S4.

[0050] Figure 4 The adjacent surface S2 of the first prism B1 and the second prism B2 is the first surface mentioned above; the adjacent surface S6 of the third prism B3 and the fourth prism B4 is the third surface mentioned above; the adjacent surface S3 of the second prism B2 and the third prism B3 is the second surface mentioned above; and the adjacent surface S4 of the second prism B2 and the third prism B3 is the fourth surface mentioned above. The fourth surface is a semi-transparent and semi-reflective surface.

[0051] Figure 4 This is merely one example of the beam-combining module 20. In some embodiments, the beam-combining module 20, including the first, second, third, and fourth surfaces described above, can be implemented without a prism. For example, using... Figure 4 Surfaces S2, S3, and S6 in the middle are replaced with total internal reflection mirrors, and Figure 4 By replacing surface S4 with a semi-transparent, semi-reflective plate, a beam combiner module 20 without a prism can also be obtained. Alternatively, only the surface S4 can be replaced. Figure 4 By partially retrieving the surface of the mirror and retaining a portion of the prism, a beam combining module 20 that contains both a mirror and a prism can be obtained.

[0052] In some embodiments, the angular differences between the first and second surfaces, and between the third and fourth surfaces, are equal. The values ​​of the two angular differences are determined based on the ratio of the dual-optical-path spacing to the calibration distance, wherein the dual-optical-path spacing is half the distance between the centers of the two receiving modules, and the calibration distance is the distance between the line connecting the centers of the two receiving modules and the observed target.

[0053] like Figure 5 As shown, A represents the observation target, a represents the dual-optical-path spacing length (which is equal to half the length of the line connecting the centers of the two receiving modules), and b represents the distance between the line connecting the centers of the two receiving modules and the observation target. Figure 5The angle θ is equal to the angle difference between the first surface and the second surface, and the angle difference between the third surface and the fourth surface. That is, the angle difference between the first surface and the second surface, and the angle difference between the third surface and the fourth surface are θ = arctan(a / b), where θ is the angle difference between the first surface and the second surface, and also the angle difference between the third surface and the fourth surface.

[0054] In some embodiments, the beam combining module 20 may include not only the first surface, second surface, third surface, and fourth surface, but may also require more reflective surfaces and semi-transparent / semi-reflective surfaces along the light propagation path. The implementation methods of the beam combining module 20 in this application cannot be exhaustively described.

[0055] In some embodiments, combined with Figure 4 and Figure 5 The beam combining module 20 includes multiple prisms arranged in a gapless manner within the objective lens tube 40. At least one pair of adjacent prisms has a semi-transparent, semi-reflective coating layer deposited on their contact surfaces. This semi-transparent, semi-reflective coating layer is used to combine the beams of light collected from the target by each light receiving module 10 from different angles into a coaxially propagating beam.

[0056] like Figure 4 As shown, the beam combiner module 20 includes multiple prisms arranged in a gapless manner within the objective lens tube 40. This structure simplifies the assembly process of the beam combiner module 20, eliminates complex optical component calibration operations, and makes it easier to replace. Therefore, the endoscope can easily replace the beam combiner module 20 to adapt to different observation angle requirements.

[0057] The main objective lens group T can be set on the light propagation path between the beam combining module 20 and the image sensor 30. Specifically, it can include multiple optical elements, such as convex lenses, concave lenses, etc.

[0058] In some embodiments, the endoscope further includes a liquid lens 50 disposed on the light propagation path between the beam combining module 20 and the image sensor 30, and the focal length of the liquid lens is dynamically changed by adjusting the liquid state in the liquid lens.

[0059] Liquid lenses typically consist of two immiscible, transparent liquids (such as oil and water), confined within a transparent container (such as a glass or polymer cavity). By external control methods (such as applying voltage, pressure, or temperature changes), the surface tension or stress state of the liquid can be altered, thereby adjusting the radius of curvature of the liquid interface (e.g., changing the liquid surface from "flat" to "convex" or "concave") or its refractive index. Since the focal length of the lens is directly related to the radius of curvature and refractive index, changes in curvature and refractive index will change the focal length of the lens in real time, achieving dynamic focusing without any moving mechanical parts. Common control mechanisms for liquid transparency include: electrowetting effect, pneumatic or hydraulic actuation, and temperature control.

[0060] Specifically, a liquid lens 50 based on the electrowetting effect can be used, which can achieve millisecond-level precise control and instantaneous switching between near and far focus ranges. The focusing function can be achieved without any mechanical movement, so that the endoscope can still output clear and magnified endoscopic images in real time when moving in complex cavity environments.

[0061] For endoscopes, a larger aperture (F#) results in lower light intake, lower image resolution, greater depth of field, and a wider field of view; conversely, a smaller aperture (F#) results in higher light intake, higher image resolution, shallower depth of field, and a smaller field of view. Currently, endoscope design cannot effectively improve both depth of field and image resolution. Therefore, depth of field is typically prioritized over image resolution and light intake in endoscope design considerations.

[0062] The current mainstream solution for commercial 3D endoscopes is a fixed-focus design using a small aperture (f / 8-f / 16) to obtain a large depth of field (>50mm) to cover the conventional field of view. While structurally simple and reliable, this design lacks fine focusing and has low light energy, resulting in poor performance. Current endoscopes typically use an aperture of F6, which offers advantages such as a large depth of field and wide visible range, but also suffers from low resolution.

[0063] This application proposes that a liquid lens 50 disposed on the light propagation path between the beam combining module 20 and the image sensor 30 can significantly improve the resolution of the image at any position outside the depth of field, thereby enabling the endoscope to improve image resolution while reducing the F# value (i.e. increasing the depth of field).

[0064] In some embodiments, the image sensor 30 includes a white light sensor 31 for white light imaging and a fluorescence sensor 32 for fluorescence imaging. Correspondingly, the endoscope also includes a beam splitter 60 disposed on the light propagation path between the beam combining module 20 and the image sensor 30. The beam splitter 60 separates the propagation directions of the white light and fluorescence in the combined beam; the separated white light is incident on the white light sensor 31, and the separated fluorescence is incident on the fluorescence sensor 32.

[0065] Furthermore, in some embodiments, the endoscope also includes a parallel plate 70 disposed on the light propagation path between the beam combining module 20 and the image sensor 30, the parallel plate 70 being used to filter out the excitation light of fluorescence.

[0066] In some embodiments, the endoscope further includes a replaceable endoscope assembly for achieving different viewing angles, the endoscope assembly including the aforementioned bundle-combining module 20.

[0067] The endoscope provided in this application provides clear images within the range of 20-200nm, and the aperture F# value is less than F5, for example, it can be F4.5, F4, F3.9, or F3.5.

[0068] This application also provides an endoscope assembly, including the bundle-combining module in any of the above-mentioned endoscopes, and different endoscope assemblies can be used to achieve different observation angles.

[0069] This application also provides a surgical microscope system, including any of the above-mentioned endoscopes and an image processor, wherein the image processor is used to process stereoscopic image information of the target observed by the endoscope, such as displaying the image, marking the image according to the user's operation, etc.

[0070] This application takes an endoscope including left and right light-receiving modules as an example and provides the following embodiments of several endoscopes.

[0071] Example 1

[0072] Figure 5 This is a schematic diagram of a 3D 4K white light microscopic endoscope imaging system (0°). The endoscope imaging system, from the object side to the image side, consists of the following components: a front negative lens group (for both left and right light paths), a prism group (for both left and right light paths), an aperture stop (for both left and right light paths sharing a common path), a main objective lens group (for both left and right light paths sharing a common path), a spacer (for both left and right light paths sharing a common path), an objective lens tube (for both left and right light paths sharing a common path), and an image sensor (white light). The main objective lens group includes a liquid lens group and a fixed lens group. The fixed lens group consists of: a filter, a spherical single lens, a cemented triplet spherical lens, a cemented doublet spherical lens, and a parallel plate. This white light endoscope imaging system has a wavelength of 415nm-670nm, a half field of view of 48°, an F# of 3.9, and a binocular calibration distance of 50mm. Through liquid lens focusing, it can achieve clear magnified images within a range of 20mm to 200mm.

[0073] Example 2

[0074] Figure 6This is a schematic diagram of a 3D 4K white light microscopic endoscope imaging system (30°). From the object side to the image side, the endoscope imaging system consists of the following components: a front negative lens group (for both left and right light paths), a prism group (for both left and right light paths), an aperture stop (for both left and right light paths sharing a common path), a main objective lens group (for both left and right light paths sharing a common path), a spacer (for both left and right light paths sharing a common path), an objective lens tube (for both left and right light paths sharing a common path), and an image sensor (white light). The main objective lens group includes a liquid lens group and a fixed lens group. The fixed lens group consists of: a filter, a spherical single lens, a cemented triplet spherical lens, a cemented doublet spherical lens, and a parallel plate. This white light endoscope imaging system has a wavelength of 415nm-670nm, a half field of view of 48°, an F# of 3.9, and a binocular calibration distance of 50mm. Through liquid lens focusing, it can achieve clear magnified images within a range of 20mm to 200mm.

[0075] The above embodiments 1 and 2 use a common optical path design. The difference between embodiment 2 and embodiment 1 lies in the prism group. In embodiment 3, the prism group is designed with an angle to ensure the system meets the 30° viewing angle requirement. The liquid lens in embodiments 1 and 2 is an optical element that achieves dynamic focusing by changing the curvature of the liquid surface. Its core principle is to use electrowetting effect or mechanical pressure to deform the transparent liquid (such as conductive solution and insulating oil) within a sealed cavity. When voltage or pressure is applied, the curvature of the liquid interface changes in real time, thereby changing the beam refraction path. Focusing can be completed in milliseconds without the need for mechanically moving parts. This technology combines the advantages of miniaturization, low power consumption, and high response speed. The MTF imaging curves of this imaging system at 20mm, 50mm, and 200mm are shown below. Figure 7 , Figure 8 , Figure 9 As shown, its resolution of 300 lp / mm is greater than 0.2. Compared with traditional fixed-focus endoscopes (200 lp / mm), the resolution of this imaging system is significantly improved.

[0076] Example 3

[0077] Figure 10 This is a schematic diagram of a 3D 4K white light-fluorescence endoscopic imaging system (0°). From the object side to the image side, the endoscopic imaging system consists of the following components: a front negative lens group (for both left and right light paths), a prism group (for both left and right light paths), an aperture stop (for both left and right light paths sharing a common path), a main objective lens group (for both left and right light paths sharing a common path), a spacer (for both left and right light paths sharing a common path), an objective lens tube (for both left and right light paths sharing a common path), and two image sensors (a white light sensor and a fluorescence sensor). The main objective lens group includes a liquid lens group and a fixed lens group. The fixed lens group consists of a filter, a spherical single lens, a cemented triplet spherical lens, a cemented doublet spherical lens, and a 45° beam-splitting prism. The beam-splitting prism is coated to reflect visible light and transmit near-infrared light.

[0078] Example 4

[0079] Figure 11 This is a schematic diagram of a 3D 4K white light-fluorescence endoscopic imaging system (30°). From the object side to the image side, the endoscopic imaging system consists of the following components: a front negative lens group (for both left and right light paths), a prism group (for both left and right light paths), an aperture stop (for both left and right light paths sharing a common path), a main objective lens group (for both left and right light paths sharing a common path), a spacer (for both left and right light paths sharing a common path), an objective lens tube (for both left and right light paths sharing a common path), and two image sensors (a white light sensor and a fluorescence sensor). The main objective lens group includes a liquid lens group and a fixed lens group. The fixed lens group consists of a filter, a spherical single lens, a cemented triplet spherical lens, a cemented doublet spherical lens, and a 45° beam-splitting prism. The beam-splitting prism is coated to reflect visible light and transmit near-infrared light.

[0080] The common optical path design in Examples 3 and 4 differs from that in the prism group. In Example 4, the prism group is designed with an angle to meet the 30° viewing angle requirement. In Examples 1 and 2, the liquid lens is an optical element that achieves dynamic focusing by changing the curvature of the liquid surface. This endoscopic imaging system is parfocal in the wavelength range of 415nm-900nm, with a half-field of view of 48°, an F# of 3.9, and a binocular calibration distance of 50mm. Focusing with the liquid lens allows for clear, magnified images to be observed within the 20mm-200mm range. The MTF imaging curves of this imaging system at 20mm, 50mm, and 200mm are shown below. Figure 12 , Figure 13 , Figure 14 As shown, its resolution of 270 lp / mm is greater than 0.2. Compared with the traditional fixed-focus fluorescence endoscope (170 lp / mm), the resolution of this imaging system is significantly improved.

[0081] The various embodiments in this application are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for hardware + program embodiments, since they are basically similar to the method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0082] The foregoing has described specific embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired results. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0083] Those skilled in the art will also know that, besides implementing the controller in the form of purely computer-readable program code, the same functions can be achieved by logically programming the method steps, making the controller take the form of logic gates, switches, application-specific integrated circuits (ASICs), programmable logic controllers (PLCs), and embedded microcontrollers. Therefore, such a controller can be considered a hardware component, and the devices within it used to implement various functions can also be considered structures within that hardware component. Alternatively, the devices used to implement various functions can be considered as both software modules implementing the method and structures within a hardware component.

[0084] The above description is merely an embodiment of the present application and is not intended to limit the embodiments of the present application. For those skilled in the art, various modifications and variations can be made to the embodiments of the present application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the embodiments of the present application should be included within the scope of the claims of the embodiments of the present application.

Claims

1. An endoscope, characterized in that, include: Two or more light-collecting modules are used to collect light beams from different angles to observe the target by the endoscope; A beam combiner module, comprising optical elements having a semi-transparent, semi-reflective surface; The beam combining module is used to combine the beams of the observed target collected by each beam collecting module into a beam that propagates coaxially through a semi-transparent and semi-reflective surface. An image sensor is used to image the light beams collected by the light-receiving module from different angles of the observed target, thereby obtaining stereoscopic image information of the endoscope-observed target.

2. The endoscope according to claim 1, characterized in that, The beam combining module also includes a reflector and / or a prism, which adjusts the beams collected by different light-collecting modules of the endoscope observation target to the semi-transparent and semi-reflective surface by combining the positions of the reflector and / or prism with the semi-transparent and semi-reflective surface.

3. The endoscope according to claim 1, characterized in that, The beam combining module includes a first surface, a second surface, a third surface, and a fourth surface; wherein the first surface, the second surface, and the third surface are total reflection surfaces, and the fourth surface is a semi-transparent and semi-reflective surface; The first and third surfaces are used to reflect beams of light collected from the observed target from different angles; The first surface is used to reflect the light beam from the observed target to the second surface, and the second surface is used to reflect the light beam to the fourth surface so that the light beam is transmitted out from the fourth surface; The third surface is used to reflect the beam of light from the observed target to the fourth surface, which then reflects the beam back out, and the reflected beam from the fourth surface coincides with the transmitted beam.

4. The endoscope according to claim 3, characterized in that, The angle difference between the first surface and the second surface, and the angle difference between the third surface and the fourth surface are equal.

5. The endoscope according to claim 3, characterized in that, The values ​​of the two angle differences are determined by the ratio of the dual-optical-path spacing length to the calibration distance. The dual-optical-path spacing length is half the distance between the centers of the front ends of the two light-receiving modules, and the calibration distance is the distance between the line connecting the centers of the front ends of the two light-receiving modules and the observed target.

6. The endoscope according to claim 1, characterized in that, The beam combining module includes multiple prisms arranged in a gapless manner within the objective lens tube; a semi-transparent and semi-reflective coating is coated on the contact surface of at least one pair of adjacent prisms; the semi-transparent and semi-reflective coating is used to combine the beams of the observed target collected from different angles by each light receiving module into a coaxially propagating beam.

7. The endoscope according to claim 1, characterized in that, The beam combining module includes a first prism, a second prism, a third prism, and a fourth prism; The second prism and the third prism are located in the middle region of the objective lens tube cross section and are used to collect the beam of light of the observed target from different angles respectively. The second prism is arranged adjacent to the third prism. The second prism and the third prism have a first adjacent surface and a second adjacent surface, wherein the first adjacent surface is a total reflection surface and the second adjacent surface is a semi-transparent and semi-reflective surface. The adjacent surfaces of the first and second prisms reflect the light beam of the observed target collected by the second prism to the first adjacent surface, and the first adjacent surface then reflects the light beam to the second adjacent surface, from which the light beam is transmitted out. The adjacent surfaces of the third and fourth prisms reflect the beam of light from the observed target collected by the third prism to the second adjacent surface, which then reflects the beam of light back out. The reflected beam from the second adjacent surface is parallel to the projected beam.

8. The endoscope according to claim 1, characterized in that, The endoscope also includes: A liquid lens is positioned on the light propagation path between the beam combining module and the image sensor. The focal length of the liquid lens is dynamically changed by adjusting the liquid state within it.

9. The endoscope according to claim 1, characterized in that, The image sensor includes a white light image sensor for white light imaging and a fluorescence sensor for fluorescence imaging; Accordingly, the endoscope also includes: A beam splitter is positioned on the light propagation path between the beam combining module and the image sensor. The beam splitter is used to separate the propagation directions of white light and fluorescence in the beam combining module. The separated white light is incident on the white light sensor, and the separated fluorescence is incident on the fluorescence sensor.

10. The endoscope according to claim 1, characterized in that, The endoscope also includes: A parallel plate is positioned on the light propagation path between the beam combining module and the image sensor. The parallel plate is used to filter out the excitation light of fluorescence.

11. The endoscope according to claim 1, characterized in that, The light receiving module includes: The front negative lens is used to focus the light and adjust the direction of the incident beam and the field of view. An optical switch, located at the front end of the front negative lens, is used to control whether the light-collecting module collects the light beam of the target observed by the endoscope.

12. An endoscope assembly, characterized in that, Includes the bundle-combining module in the endoscope according to any one of claims 1 to 11.

13. A surgical microscope system, characterized in that, include: The endoscope according to any one of claims 1 to 11; An image processing device is used to process the stereoscopic image information of the target observed by the endoscope.

Images