A rotating endoscopic OCT probe

Abstract

The present application provides a rotating endoscopic OCT probe, the technical solution of which is as follows: it includes a transparent catheter and an optical fiber for extending into biological tissue, the optical fiber is arranged in the transparent catheter, and is used to transmit light emitted by a light source, and is characterized in that the transparent catheter also includes: a self-focusing lens for converging light; a right-angle prism for reflecting the light converged by the self-focusing lens to a direction perpendicular to the transparent catheter; a cylindrical mirror for receiving light reflected by the right-angle prism, the side of the cylindrical mirror close to the right-angle prism is a plane, and the other side is a convex surface, and silicone oil is arranged between the cylindrical mirror and the transparent catheter. The rotating endoscopic OCT probe provided by the present application has the advantages of high imaging resolution, small size, and compact structure.

Description

Technical Field

[0001] The present application relates to the field of medical imaging technology, and in particular to a rotating endoscopic OCT probe. Background Art

[0002] Since traditional medical endoscopes can only observe lesions on the surface of internal organs, and lesions often occur first in the fault layer of the organ, ultrasound imaging technology is introduced to expand the function of the endoscope. However, the resolution of ultrasound imaging is in the millimeter level, far from the micron level. Although the OCT resolution is sufficient, because the imaging depth of OCT technology is shallow, it can only image the subcutaneous tissue at a depth of about a few millimeters. Therefore, a catheter-based fiber optic OCT endoscope system is proposed, which combines OCT technology with a catheter or endoscope for in vivo detection, and detects internal organisms such as the respiratory tract, digestive tract, urinary system, and cardiovascular system, to achieve non-destructive cross-sectional imaging of the living body, thereby avoiding the destructive method of making pathological sections of diseased tissues.

[0003] However, the currently commonly used small-sized rotating endoscopic OCT probe can be regarded as a lens because the catheter itself affects the light, thus amplifying the light spot and reducing the resolution. The existing fiber optic catheter OCT can be made small in size for in vivo examination, but the resolution is generally poor and cannot optically compensate for the impact of the catheter.

[0004] In view of the above problems, the inventor provides a solution. Summary of the invention

[0005] The purpose of the present application is to provide a rotating endoscopic OCT probe having the advantages of high imaging resolution, small size and compact structure.

[0006] In the first aspect, the embodiment of the present application provides a rotating endoscopic OCT probe, and the technical solution is as follows:

[0007] The invention comprises a transparent catheter and an optical fiber for inserting into biological tissue. The optical fiber is arranged in the transparent catheter and is used to transmit light emitted by a light source. The transparent catheter also comprises:

[0008] Self-focusing lenses, used to converge light;

[0009] A right-angle prism, used to reflect the light converged by the self-focusing lens to a direction perpendicular to the transparent catheter;

[0010] The cylindrical mirror is used to receive the light reflected by the right-angle prism. The side of the cylindrical mirror close to the right-angle prism is a flat surface, and the other side is a convex surface. Silicone oil is arranged between the cylindrical mirror and the transparent conduit.

[0011] An optical fiber, a self-focusing lens, a right-angle prism and a cylindrical mirror are arranged inside a transparent catheter, and the transparent catheter is extended into the interior of a biological tissue to detect internal organisms such as the respiratory tract, digestive tract, urinary system and cardiovascular system, so as to achieve non-destructive cross-sectional imaging of a living body, wherein the optical fiber is used to transmit light, and the light is emitted from the optical fiber, incident on the self-focusing lens, the right-angle prism, the cylindrical mirror, the silicone oil, the transparent catheter and finally irradiated on the biological tissue. In the existing technical solution, the transparent catheter will act on the light, resulting in a decrease in imaging resolution. In the solution of the present application, a cylindrical mirror is arranged at the right-angle prism, and the cylindrical mirror is used to compensate for the influence of the transparent catheter itself, thereby improving the imaging resolution.

[0012] Furthermore, in an embodiment of the present application, the gradient constant of the self-focusing lens is 1.34, the central refractive index is 1.616, and the thickness is 1.173 mm.

[0013] Furthermore, in the embodiment of the present application, the right-angle prism is bonded to the self-focusing lens, and the thickness of the right-angle prism is 0.5 mm.

[0014] Furthermore, in an embodiment of the present application, the cylindrical mirror is bonded to the right-angle prism, and the convex surface curvature radius of the cylindrical mirror is -5.2 mm and the thickness is 0.1 mm.

[0015] Furthermore, in the embodiment of the present application, the distance between the cylindrical mirror and the inner wall of the transparent tube is 0.276 mm, and the radius of curvature of the inner wall of the transparent tube is -0.65 mm.

[0016] Furthermore, in the embodiment of the present application, the thickness of the transparent tube is 0.1 mm, and the radius of curvature of the outer wall of the transparent tube is -0.75 mm.

[0017] Furthermore, in an embodiment of the present application, a connecting tube is provided between the self-focusing lens and the optical fiber, and the distance between the self-focusing lens and the optical fiber is 0.148 mm.

[0018] Furthermore, in the embodiment of the present application, a spring is also provided in the transparent conduit, and the connecting tube is provided on the spring.

[0019] Furthermore, in an embodiment of the present application, the refractive index n of the self-focusing lens satisfies:

[0020] ;

[0021] Wherein, r represents the radius of the self-focusing lens at different positions.

[0022] Furthermore, in the embodiment of the present application, both side surfaces of the self-focusing lens are provided with anti-reflection films, and the reflective surface of the right-angle prism is provided with a gold film.

[0023] As can be seen from the above, the present application provides a rotating endoscopic OCT probe, in which an optical fiber, a self-focusing lens, a right-angle prism and a cylindrical mirror are arranged inside a transparent catheter, and the transparent catheter is extended into the interior of biological tissue to detect internal organisms such as the respiratory tract, digestive tract, urinary system and cardiovascular system, so as to achieve non-destructive cross-sectional imaging of living bodies, wherein the optical fiber is used to transmit light, and the light is emitted from the optical fiber, and the incident light passes through the self-focusing lens, the right-angle prism, the cylindrical mirror, the silicone oil, the transparent catheter and finally irradiates the biological tissue. In the existing technical scheme, the transparent catheter will act on the light, resulting in a decrease in imaging resolution. In the scheme of the present application, a cylindrical mirror is arranged at the right-angle prism, and the cylindrical mirror is used to compensate for the influence of the transparent catheter itself, thereby improving the imaging resolution, and has the beneficial effects of high imaging resolution, small size and compact structure.

[0024] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by practicing the embodiments of the present application. The purpose and other advantages of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of the structure of a rotating endoscopic OCT probe provided in an embodiment of the present application.

[0026] Figure 2 A schematic diagram of the structure of a rotating endoscopic OCT probe provided in an embodiment of the present application.

[0027] Figure 3 A light path diagram of a rotating endoscopic OCT probe provided in an embodiment of the present application.

[0028] Figure 4 This is the output spot size diagram after correction using a cylindrical mirror.

[0029] Figure 5 This is the output spot size diagram without cylindrical mirror correction.

[0030] Figure 6 This is the MTF curve after correction using a cylindrical mirror.

[0031] Figure 7 This is the MTF curve without cylindrical lens correction.

[0032] In the figure: 100, transparent catheter; 200, optical fiber; 300, self-focusing lens; 400, right-angle prism; 500, cylindrical mirror; 600, spring; 700, connecting tube. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0034] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0035] Please refer to Figures 1 to 7 A rotary endoscopic OCT probe, the technical solution of which specifically includes a transparent catheter 100 and an optical fiber 200 for inserting into biological tissue, the optical fiber 200 is arranged in the transparent catheter 100, and is used to transmit light emitted by a light source, and the transparent catheter 100 also includes the following arranged in sequence along the direction of light from the optical fiber 200 incident to the biological tissue:

[0036] A self-focusing lens 300 for converging light;

[0037] The right angle prism 400 is used to reflect the light converged by the self-focusing lens 300 to a direction perpendicular to the transparent catheter 100;

[0038] The cylindrical mirror 500 is used to receive the light reflected by the right-angle prism 400 . The side of the cylindrical mirror 500 close to the right-angle prism 400 is a flat surface, and the other side is a convex surface. Silicone oil is arranged between the cylindrical mirror 500 and the transparent conduit 100 .

[0039] Through the above technical solution, the optical fiber 200, the self-focusing lens 300, the right-angle prism 400 and the cylindrical mirror 500 are arranged in the transparent catheter 100, and the transparent catheter 100 is extended into the biological tissue to detect the internal organism such as the respiratory tract, digestive tract, urinary system and cardiovascular system or other positions, so as to achieve non-destructive cross-sectional imaging of the living body, wherein the optical fiber 200 is used to transmit light, and the light is emitted from the optical fiber 200, incident on the self-focusing lens 300, the right-angle prism 400, the cylindrical mirror 500, the silicone oil, the transparent catheter 100 and finally irradiated on the biological tissue. In the existing technical solution, the transparent catheter 100 will act on the light, resulting in a decrease in imaging resolution. In the solution of the present application, a cylindrical mirror 500 is arranged at the right-angle prism 400, and the cylindrical mirror 500 is used to compensate for the influence of the transparent catheter 100 itself, thereby improving the imaging resolution.

[0040] Further, in some of the embodiments, the gradient constant of the self-focusing lens 300 is 1.34, the central refractive index is 1.616, and the thickness is 1.173 mm. The right angle prism 400 is bonded to the self-focusing lens 300, and the thickness of the right angle prism 400 is 0.5 mm. The cylindrical mirror 500 is bonded to the right angle prism 400, and the convex curvature radius of the cylindrical mirror 500 is -5.2 mm and the thickness is 0.1 mm. The distance between the cylindrical mirror 500 and the inner wall of the transparent conduit 100 is 0.276 mm, and the curvature radius of the inner wall of the transparent conduit 100 is -0.65 mm. The thickness of the transparent conduit 100 is 0.1 mm, and the curvature radius of the outer wall of the transparent conduit 100 is -0.75 mm. A connecting tube 700 is provided between the self-focusing lens 300 and the optical fiber 200, and the distance between the self-focusing lens 300 and the optical fiber 200 is 0.148 mm.

[0041] Specifically, the specific design parameters of the optical system are shown in the following table:

[0042]

[0043] Wherein, the refractive index n of the self-focusing lens 300 satisfies:

[0044] ;

[0045] Wherein, r represents the radius of the self-focusing lens 300 at different positions.

[0046] Δt is the maximum step size. Δt determines the relationship between the speed and accuracy of the simulated refractive index. The speed is inversely proportional to the accuracy.

[0047] Through the above technical solution, the optical system designed by using the above parameters is not only compact in structure, but also has ultra-high resolution and excellent imaging quality. The light is emitted from the optical fiber 200 and irradiated on the self-focusing lens 300. The self-focusing lens 300 is a gradient 5 The lens has two end faces that are both flat and 1.173 mm thick. The light is focused by the self-focusing lens 300 while passing through it. The focused light enters the right-angle prism 400 that is bonded to the self-focusing lens 300. The right-angle prism 400 deflects the light by 90°, and the deflected light enters the cylindrical mirror 500. The cylindrical mirror 500 is a plano-convex lens with a thickness of 0.1 mm and a radius of curvature of -5.2 mm. After being focused by the cylindrical mirror 500, the light passes through the silicone oil between the cylindrical mirror 500 and the transparent pipe. The silicone oil here is equivalent to a lens. The distance between the cylindrical mirror 500 and the inner wall of the transparent conduit 100 is 0.276 mm, which is equivalent to the silicone oil forming a lens with a thickness of 0.276 mm that is bonded to the cylindrical mirror 500 and the transparent conduit 100. After passing through the silicone oil, the light enters the transparent catheter 100, which is cylindrical, and the light is emitted from the inside of the transparent catheter 100 to the outside. Therefore, the transparent catheter 100 is equivalent to forming a concave-convex lens. The inner wall curvature radius of the transparent tube is -0.65 mm, and the outer wall curvature radius is -0.75 mm. After passing through the transparent tube, the light irradiates the biological tissue, and then the reflected light returns along the light path to form an image.

[0048] Specific as Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, Figure 5 This is the output spot size diagram obtained when the cylindrical mirror 500 is not used for correction. Figure 4 This is the output spot size diagram after correction using cylindrical mirror 500. Figure 7 This is the MTF curve obtained when the cylindrical mirror 500 is not used for correction. Figure 6 This is the mtf curve obtained after correction using the cylindrical mirror 500. According to this design, the solution provided by the present application can achieve a resolution of an astonishing 0.02 microns.

[0049] Furthermore, in some of the embodiments, a spring 600 is further disposed in the transparent catheter 100 , and the connecting tube 700 is disposed on the spring 600 .

[0050] In some specific implementations, the spring 600 is a spring 600 drawn from 304 stainless steel piano wire, with an inner diameter of 0.7 mm and an outer diameter of 1.2 mm.

[0051] Through the above technical solution, when the probe is working, the spring 600 can provide a rotational torque to the probe, so that the internal optical component can rotate.

[0052] Furthermore, in some of the embodiments, both side surfaces of the self-focusing lens 300 are provided with anti-reflection films, and the reflective surface of the right-angle prism 400 is provided with a gold film.

[0053] Through the above technical solution, the anti-reflection film is used to increase the light transmission performance, so that the light can pass through the lens to the greatest extent, reduce energy loss, and thus improve the image quality. Providing a gold film on the reflective surface of the right-angle prism 400 can increase the reflectivity of the light, and can also reduce light loss, thereby improving the image quality.

[0054] Specifically, in some preferred embodiments, the main structure of a rotating endoscopic OCT probe provided by the present application is composed of an optical fiber 200, a self-focusing lens 300, a connecting tube 700, a right-angle prism 400, a cylindrical mirror 500, a spring 600, and a transparent catheter 100.

[0055] Among them, the optical fiber 200 and the self-focusing lens 300 are respectively bonded to the two ends of the connecting tube 700 by dispensing, the right-angle prism 400 is bonded to the self-focusing lens 300, the cylindrical mirror 500 is bonded to the right-angle prism 400, and the connecting tube 700 is welded to the spring 600. All the above components are sleeved in the transparent conduit 100, and the transparent conduit 100 is filled with silicone oil. The above components are soaked in the silicone oil, and the silicone oil can also play a role of lubrication. Specifically, UV305 and 353ND can be used for dispensing.

[0056] The optical fiber 200 is a 9 / 125 single-mode optical fiber 200. A glass tube is provided at the front end of the optical fiber 200. The end face of the glass tube is ground by a grinder so that the end face finish meets the requirements of the lens level. An anti-reflection film is provided to improve the transmittance.

[0057] The connecting tube 700 is made of medical grade stainless steel 304 capillary tube with an inner diameter of 0.5 mm and an outer diameter of 0.7 mm, and is drawn by a machine and then cut by a laser.

[0058] The self-focusing lens 300 is made of aluminosilicate glass with a gradient constant of 1.340, a central refractive index of 1.616, and NA0.53, with a diameter of 0.5 mm. Both end surfaces are coated with anti-reflection films to improve transmittance.

[0059] The right-angle prism 400 is made of N-BK7, and its right-angle length is 0.5 mm. A gold film is provided on the reflection surface to improve the reflectivity.

[0060] The cylindrical mirror 500 is made of N-BK7 and is a plano-convex lens with a thickness of 0.1 mm and a radius of curvature of -5.2 mm.

[0061] The transparent conduit 100 is a hose made of highly transparent PEBAX material PA5533 produced by Arkema of France, and is used to wrap all components.

[0062] Among them, the silicone oil Shin-Etsu produces high-refractive index and high-vacuum silicone oil.

[0063] The design parameters of the optical system composed of the above components are the same as the parameter table in the above embodiment.

[0064] By using the above design, the resolution drop caused by the transparent catheter 100 is effectively calibrated through the cylindrical mirror 500, so that the imaging resolution can reach 0.02 microns, which is far superior to conventional probes on the market and is a significant improvement.

[0065] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A rotary endoscopic OCT probe, comprising a transparent catheter (100) for inserting into biological tissue and an optical fiber (200), wherein the optical fiber (200) is arranged in the transparent catheter (100) and is used to transmit light emitted by a light source, characterized in that: The transparent catheter (100) further comprises: A self-focusing lens (300) for converging light; A right-angle prism (400) for reflecting the light rays converged by the self-focusing lens (300) in a direction perpendicular to the transparent conduit (100); The cylindrical mirror (500) is used to receive light reflected by the right-angle prism (400); one side of the cylindrical mirror (500) close to the right-angle prism (400) is a flat surface, and the other side is a convex surface; silicone oil is provided between the cylindrical mirror (500) and the transparent conduit (100).

2. A rotary endoscopic OCT probe according to claim 1, characterized in that: The self-focusing lens (300) has a gradient constant of 1.34, a central refractive index of 1.616, and a thickness of 1.173 mm.

3. The rotary endoscopic OCT probe according to claim 2, characterized in that: The right-angle prism (400) is bonded to the self-focusing lens (300), and the thickness of the right-angle prism (400) is 0.5 mm.

4. The rotary endoscopic OCT probe according to claim 3, characterized in that: The cylindrical mirror (500) is bonded to the right-angle prism (400), and the convex surface curvature radius of the cylindrical mirror (500) is -5.2 mm and the thickness is 0.1 mm.

5. The rotary endoscopic OCT probe according to claim 4, characterized in that: The distance between the cylindrical mirror (500) and the inner wall of the transparent tube (100) is 0.276 mm, and the radius of curvature of the inner wall of the transparent tube (100) is -0.65 mm.

6. The rotary endoscopic OCT probe according to claim 5, characterized in that: The thickness of the transparent tube (100) is 0.1 mm, and the radius of curvature of the outer wall of the transparent tube (100) is -0.75 mm.

7. The rotary endoscopic OCT probe according to claim 1, characterized in that: A connecting tube (700) is provided between the self-focusing lens (300) and the optical fiber (200), and the distance between the self-focusing lens (300) and the optical fiber (200) is 0.148 mm.

8. The rotary endoscopic OCT probe according to claim 7, characterized in that: A spring (600) is also arranged inside the transparent catheter (100), and the connecting tube (700) is arranged on the spring (600).

9. The rotary endoscopic OCT probe according to claim 1, characterized in that: The refractive index n of the self-focusing lens (300) satisfies: ； Wherein, r represents the radius of the self-focusing lens (300) at different positions.

10. The rotary endoscopic OCT probe according to claim 1, characterized in that: Both side surfaces of the self-focusing lens (300) are provided with anti-reflection films, and the reflection surface of the right-angle prism (400) is provided with a gold film.

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