A fiber-optic bundle-coupled ultraviolet laser ablation system

Abstract

This invention discloses a fiber-optic bundled ultraviolet laser ablation system, relating to the field of medical devices. The system includes a laser, a beam homogenizing component, and a fiber-optic bundled component. The laser emits laser light; the beam homogenizing component is disposed on the output optical path of the laser; the fiber-optic bundled component is disposed on the output optical path of the beam homogenizing component; the beam homogenizing component performs beam flat-top shaping and beam superposition on the laser to obtain a target spot; the fiber-optic bundled component performs multi-beam transmission of the target spot. This invention can achieve laser ablation efficiently and stably.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and in particular to a fiber optic bundle-coupled ultraviolet laser ablation system. Background Technology

[0002] For chronic occlusive lesions, thrombosis, and coexisting atherosclerotic plaques and calcified tissue lesions in blood vessels, arterial interventional therapy is generally used. This involves inserting a catheter into the blood vessel and using the principle of laser ablation to eliminate plaques and proliferating tissue, thereby clearing the blocked or narrowed blood vessels and achieving safe treatment without damaging the blood vessels.

[0003] Laser application to biological tissues produces a series of biological effects, such as photochemical, thermal, and mechanical effects. High-peak-power pulsed ultraviolet lasers with pulse widths in the nanosecond range possess high photon energy, which can directly disrupt the chemical bonds between biological tissue molecules and break down large molecular compounds into small fragments, particles smaller than 20 μm in size. These fragments are ultimately absorbed by the reticuloendothelial system, thus preventing microvascular blockage. When 355nm ultraviolet lasers ablate thrombi and other diseased tissues, the photochemical effect plays a major role, while the thermal effect is relatively minor.

[0004] Currently, the diameter of ultraviolet laser ablation catheters is relatively small, limiting the number and area of ​​ablation fibers that can be accommodated within the catheter. This restricts the acceptable laser energy at the fiber input end and easily damages the fiber end face, resulting in unsatisfactory tissue ablation effects. Therefore, it is crucial to improve fiber coupling efficiency and output stable laser energy without damaging the fiber input end face. Summary of the Invention

[0005] The purpose of this invention is to provide an optical fiber bundle coupling ultraviolet laser ablation system that can achieve laser ablation efficiently and stably.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A fiber-optic bundle-coupled ultraviolet laser ablation system, the system comprising: a laser, a beam homogenizing component, and a fiber-optic bundle-coupled component;

[0008] The laser is used to emit laser light;

[0009] The beam homogenizing component is disposed in the output optical path of the laser; the fiber optic bundle combining component is disposed in the output optical path of the beam homogenizing component.

[0010] The beam homogenizing component is used to perform beam flat-top shaping and beam superposition of the laser to obtain the target beam spot;

[0011] The fiber optic bundle combiner is used to transmit multiple beams of the target light spot.

[0012] Optionally, the homogenizing component includes a diffractive optical component.

[0013] Optionally, the diffractive optical component is a holographic diffuser.

[0014] Optionally, the light-diffusing component includes:

[0015] A microlens group is disposed in the output optical path of the laser to perform beam flat-top shaping of the laser beam to obtain a shaped beam;

[0016] A focusing lens is disposed in the outgoing light path of the shaping beam to superimpose the shaping beam and obtain the target light spot.

[0017] Optionally, the focusing lens is a plano-convex lens or a biconvex lens.

[0018] Optionally, the fiber optic bundle assembly includes: a large-core silica fiber, a bundled input fiber, a tapered bundled fiber, and a bundled output fiber;

[0019] The large-core silica fiber is disposed in the output optical path of the uniform light assembly; the large-core silica fiber is connected to the tapered bundled fiber via the bundled input fiber; the output end of the tapered bundled fiber is connected to the bundled output fiber.

[0020] Optionally, the bundled input fiber includes multiple bundles of small-core quartz optical fibers.

[0021] Optionally, the core diameter of the large-core silica optical fiber is greater than 600 μm.

[0022] Optionally, the core diameter of the small-diameter silica optical fiber is less than 200 μm.

[0023] Optionally, the fiber optic bundle assembly includes: a protective sleeve;

[0024] The protective sleeve covers the surface of the large-core quartz optical fiber.

[0025] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0026] This invention provides a fiber-optic bundled ultraviolet laser ablation system, comprising: a laser, a beam homogenizing component, and a fiber-optic bundled component; the laser is used to emit laser light; the beam homogenizing component is disposed in the output optical path of the laser; the fiber-optic bundled component is disposed in the output optical path of the beam homogenizing component; the beam homogenizing component is used to perform beam flat-top shaping and beam superposition on the laser to obtain a target spot; the fiber-optic bundled component is used to transmit multiple beams of the target spot; because the beam flat-top shaping and beam superposition by the beam homogenizing component can make the laser energy distribution uniform, and then the fiber-optic bundled component transmits multiple beams of the target spot, increasing the receiving area, thereby avoiding damage incident and achieving the purpose of uniform energy application. Therefore, laser ablation can be achieved efficiently and stably. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a structural diagram of the fiber-optic bundle-coupled ultraviolet laser ablation system provided in an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of an optical fiber combining assembly provided in an embodiment of the present invention;

[0030] Figure 3 A schematic cross-sectional view of the bundled input optical fiber provided in an embodiment of the present invention;

[0031] Figure 4 A schematic diagram of the bundled output optical fiber provided in an embodiment of the present invention;

[0032] Figure 5 This is a schematic diagram of an ablation system in practical applications.

[0033] Symbol explanation:

[0034] Laser-1, Beam homogenizer-2, Fiber optic bundler-3, Large-core silica fiber-4, Bundled input fiber-5, Tapered bundled fiber-6, Bundled output fiber-7, Silica capillary-8, Small-core silica fiber-9, Connector-10, Handle-11, Output port-12, Guide wire-13, Microlens group-14, Focusing lens-15. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] The purpose of this invention is to provide an optical fiber bundle coupling ultraviolet laser ablation system that can achieve laser ablation efficiently and stably.

[0037] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] like Figures 1-5 As shown, this embodiment of the invention provides a fiber-optic bundled ultraviolet laser ablation system, which includes: a laser 1, a beam homogenizing component 2, and a fiber-optic bundled component 3.

[0039] Laser 1 is used to emit laser light; homogenizing component 2 is set in the output optical path of the laser; fiber optic bundle combiner 3 is set in the output optical path of homogenizing component 2; homogenizing component 2 is used to perform beam flat-top shaping and beam superposition of the laser to obtain the target spot; fiber optic bundle combiner 3 is used to transmit the target spot in multiple beams.

[0040] Specifically, the light-diffusing component 2 includes a diffractive optical component, which is a holographic diffuser.

[0041] The beam homogenizing component 2 includes a microlens group 14 and a focusing lens 15. The microlens group 14 is disposed in the output light path of the laser beam; the focusing lens 15 is disposed in the output light path of the beam shaping component. The focusing lens 15 is a plano-convex lens or a biconvex lens.

[0042] The microlens group 14 is used to flatten the laser beam to obtain a shaped beam; the focusing lens 15 is used to superimpose the shaped beam to obtain the target spot.

[0043] The fiber optic bundle assembly 3 includes: a large-core silica fiber 4, a bundle input fiber 5, a tapered bundle fiber 6, and a bundle output fiber 7.

[0044] Large-core quartz fiber 4 is placed in the output optical path of the uniform light assembly 2; the core diameter of the large-core quartz fiber 4 is greater than 600μm.

[0045] Large-core silica fiber 4 is connected to tapered bundled fiber 6 via bundled input fiber 5; the output end of tapered bundled fiber 6 is connected to bundled output fiber 7. Bundled input fiber 5 includes multiple bundles of small-core silica fibers 9. The core diameter of the small-core silica fibers 9 is less than 200 μm.

[0046] In one embodiment, the fiber bundle assembly 3 further includes a protective sleeve; the protective sleeve covers the surface of the large-core quartz fiber 4.

[0047] In practical applications, the wavelength range of the ultraviolet laser is selected to be 200nm-400nm. The homogenizing component 2 is a coupling device for receiving ultraviolet laser energy, and the fiber bundle combining component 3 is a conductor device for transmitting laser energy. When the laser passes through the array composed of microlens group 14, the microlens group 14 performs beam flat-top shaping on the laser and divides the input laser spot. Then, the multiple small beams of the divided spot are superimposed by the subsequent focusing lens 15 to obtain a homogenized light field distribution. This reduces the laser energy intensity received per unit area at the fiber incident end, thereby avoiding damage to the end face of the incident end and forming a uniform target spot.

[0048] The fiber bundle assembly 3, with a core numerical aperture ranging from 0.22 to 0.50, effectively transmits laser energy from a single large-diameter fiber with a core diameter of over 600 μm to multiple small-diameter fibers via a laser ablation conduit, thus achieving a compact laser ablation system that integrates uniform spot distribution and fiber coupling.

[0049] The fiber optic bundle assembly 3 connects large-core-diameter silica fiber 4 to tapered bundled fiber 6 via bundled input fiber 5 through fusion splicing. Bundled input fiber 5 includes multiple bundles of small-core-diameter silica fiber 9. A silica capillary tube 8 is used to bundle the multiple bundles of small-core-diameter silica fiber 9.

[0050] A tapered fiber bundle 6 is encased within a quartz capillary tube 8, effectively transmitting laser energy from a single large-core fiber to multiple small-core quartz fibers 9. The core diameter of the small-core quartz fibers 9 is below 200 μm. The fiber bundle composed of multiple small-core quartz fibers 9 includes an input end, a tapered end, and an output end. The two ends of the tapered end have different diameters; the larger end of the tapered end connects to the output end, and the smaller end connects to the input end. Both the tapered end and the input end are located within the front end of the quartz capillary tube 8, while the output end is located at the rear end of the quartz capillary tube 8 and extends outward. The large-core quartz fiber 4 is positioned behind the focusing lens 15 in the optical path. The microlens group 14 homogenizes the laser energy emitted from the laser 1, and the large-core quartz fiber 4 receives the homogenized laser energy.

[0051] The laser 1 has a pulse width of less than 15 nanoseconds or sub-nanoseconds and a wavelength of 200nm-400nm; the homogenizing component 2 may have one or two microlens arrays; the homogenizing component 2 may be a diffractive optical element; furthermore, the homogenizing component 2 may be a holographic diffuser. The focusing lens 15 is a plano-convex lens or a biconvex lens.

[0052] Furthermore, a protective sleeve can be wrapped around the surfaces of the large-core quartz fiber 4 and the quartz capillary tube 8. The fiber optic bundle assembly 3 can also be configured with an SMA fiber optic connector, with the large-core quartz fiber 4 connected to one end of the connector and the tapered bundled fiber 6 connected to the other end. Alternatively, the fiber optic bundle assembly 3 can be configured to consist only of tapered fiber bundles.

[0053] Current research has found that the effective energy density of ultraviolet laser ablation systems needs to reach 40 mJ / mm². 2 -60mJ / mm 2 The high peak energy of 355nm ultraviolet lasers with a pulse width of nanoseconds can directly damage the end face of the fiber optic input, making fiber coupling difficult. Large-core silica fiber 4 is typically used as the conductor, but its large bending radius makes it unsuitable for use as a laser ablation catheter within blood vessels. Using multiple bundles of small-core silica fiber 9 as the catheter conductor, due to the fiber's flexibility and smaller bending radius, allows for its application in intravascular laser ablation.

[0054] Using the fiber bundle assembly 3 as the final conductor, with a single large-core quartz fiber 4 at the front end, better transmits the homogenized laser energy to the small-core quartz fiber 9, and avoids directly damaging the end face of multiple fiber bundles.

[0055] Furthermore, the ablation fiber can be a single fiber with a large core diameter, or a fiber bundle composed of multiple ultraviolet multimode fibers. The single large-core silica fiber 4 has high structural strength and is not easily broken or damaged during use; while the ultraviolet multimode fiber used in the fiber bundle assembly 3 can effectively ensure the stability of its working performance. Each has its advantages, and the choice can be made according to the actual situation.

[0056] The fiber-optic bundled ultraviolet laser ablation system provided by this invention solves the problems in fiber coupling and can be applied to ultraviolet light with a wavelength of 266nm or other common wavelengths of light, such as 1064nm.

[0057] Figure 2 This is a schematic diagram of an optical fiber bundle assembly, including a single large-core silica fiber 4, a bundled input fiber 5, a tapered bundled fiber 6, and a bundled output fiber 7. The bundled input fiber 5 is composed of multiple bundles of small-core silica fibers 9. The tapered bundled fiber 6 is located on the output side of the bundled input fiber 5. The tapered end face of the bundled input fiber 5 is fused to one end of the large-core silica fiber 4. The fused bundled output fiber 7 serves as the output of the optical fiber bundle assembly 3. To improve the coupling efficiency between the bundled output fiber 7 and the large-core silica fiber 4, it is preferable that the core diameter of the large-core silica fiber 4 is similar to the core diameter of the bundled input fiber 5.

[0058] The bundled input fiber 5 includes multiple input fibers. In some embodiments, these multiple input fibers are composed of multiple power transmission fibers, such as... Figure 3 As shown in the cross-sectional structural diagram, the bundled input fiber 5 consists of at least 7 power-transmitting fibers bundled together, with a core diameter ranging from less than 200 μm. The fiber bundling method primarily employs a quartz capillary 8, including a circular capillary with an inner diameter of 0.80 mm-1.00 mm, an outer diameter of 1.05 mm-1.25 mm, and a length of 100 mm-200 mm. Multiple small-core quartz fibers 9 are inserted into a pre-set low-refractive-index fluorine-doped glass tube after removing their coating. In some embodiments, the coating is first removed from one end of each of the 7 fibers, and the bare fibers are then arranged in a neat hexagonal pattern and inserted into the low-refractive-index glass tube. The end-face arrangement of the bundled fibers is as follows: Figure 3 As shown. After the fiber bundle is completed, fusion tapering is performed in a predetermined area on the input side of the input fiber 5. The length of the taper region is determined to be 10mm-30mm, for example, 20mm. The diameter of the output end interface is tapered to approximately 450μm-750μm, and in some embodiments, it is 600μm. After high-temperature fusion splicing on a fusion splicer, the fiber bundle is well and tightly fixed together. After fusion tapering, a large-core fiber cleaver is used to cut the tapered area, and the cut end face is shown in the attached figure. Figure 3 Then, the tapered end face of the cut fiber bundle is fused to one end of the large-core quartz fiber 4 using a carbon dioxide laser fusion splicing method.

[0059] Figure 4 This is a schematic diagram of the laser conduit, specifically the bundled output fiber 7, according to an embodiment of the present invention. The connecting end 10 of the laser conduit is equipped with the aforementioned large-core diameter quartz fiber 4. The large-core diameter quartz fiber 4 is used as a connector in the laser conduit, allowing for easy connection to the laser beam homogenizing component 2. Furthermore, since the fiber inside the front end of the laser conduit is not fixed with adhesive, the thermal impact on human tissue is reduced during high-energy, short-pulse-width, and effective ablation treatment. The Y-shaped handle 11 of the laser conduit is equipped with the aforementioned fiber bundle assembly 3. The fiber bundle assembly 3 is used as a conductor device in the laser conduit, effectively transmitting the beam to the rear end of the laser conduit, serving as the output port 12. In one possible implementation, the cavity of the laser conduit includes an ablation fiber and a guidewire 13. The ablation fiber is used to transmit the target beam, and the guidewire 13 can be controlled to guide the rear end of the laser conduit to a designated location in the blood vessel. The diameter of the ablation fiber is smaller than the diameter of the guidewire 13, and the ablation fiber, guidewire 13, and conduit cavity are non-coaxial, meaning they are eccentrically positioned within the conduit cavity.

[0060] Figure 5This is a schematic diagram of an ablation system in practical applications. This fiber optic coupling system has better performance than existing technologies. The laser guide, i.e., the connection port of the bundled output fiber 7, has a high structural strength of a single large-core quartz fiber 4, which is not easily broken or damaged during use. The use of ultraviolet multimode fiber ensures the stability of its working performance.

[0061] Advantages of this invention:

[0062] 1. In the ultraviolet laser ablation system coupled by the fiber optic bundle combining assembly, there are a beam homogenizing assembly and a fiber optic bundle combining assembly. When the laser passes through the microlens group, the microlens group performs beam flat-top shaping on the laser beam. Subsequently, the segmented light spots are superimposed by the focusing lens to form a uniform energy distribution, thereby reducing the laser energy intensity received per unit area at the incident end of the large-core quartz fiber. By distributing and homogenizing the laser energy and increasing the area used to receive the laser, damage to the end face of the incident end is avoided, and the purpose of applying energy evenly is achieved.

[0063] 2. The fiber optic bundle assembly effectively transmits homogenized laser energy from a single large-core silica fiber to multiple small-core silica fibers through fusion splicing, avoiding direct damage to the end face of the small-core silica fiber incident end. It also simplifies the entire fiber coupling and laser energy transmission system, and can easily achieve effective laser ablation of tissues.

[0064] 3. The homogenized coupled ultraviolet laser ablation system improves the coupling efficiency of laser energy, reduces the requirement for laser excitation energy intensity, and can accommodate smaller and lighter lasers, making it more practical.

[0065] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0066] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the system and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A fiber-optic bundle-coupled ultraviolet laser ablation system, characterized in that, The system includes: a laser, a beam homogenizing component, and an optical fiber combining component; The laser is used to emit laser light; The beam homogenizing component is disposed in the output light path of the laser; the fiber optic bundle combining component is disposed in the output light path of the beam homogenizing component. The beam homogenizing component is used to perform beam flat-top shaping and beam superposition of the laser to obtain the target beam spot; The fiber optic bundle combiner is used to transmit multiple beams of the target light spot. The fiber optic bundle assembly includes: a large-core quartz fiber, a bundled input fiber, a tapered bundled fiber, and a bundled output fiber. The large-core silica fiber is disposed in the output optical path of the uniform light assembly; the large-core silica fiber is connected to the tapered bundled fiber via the bundled input fiber; the output end of the tapered bundled fiber is connected to the bundled output fiber. The bundled input fiber consists of multiple input fibers. A fused tapered section is formed in a predetermined area on the input side of the bundled input fiber. The length of the tapered section is determined to be 10mm-30mm. The diameter of the output end interface is tapered to 450μm-750μm. After fused tapering, the waist area is cut with a large-core fiber cleaver. The tapered end face of the cut fiber bundle is fused to one end of a large-core silica fiber using a carbon dioxide laser fusion splicing method. The bundled input fiber includes multiple small-core-diameter quartz optical fibers; The core diameter of the large-diameter silica optical fiber is greater than 600 μm; The core diameter of the small-diameter quartz optical fiber is less than 200 μm.

2. The fiber-optic bundle-coupled ultraviolet laser ablation system according to claim 1, characterized in that, The homogenizing component includes a diffractive optical component.

3. The fiber-optic bundled ultraviolet laser ablation system according to claim 2, characterized in that, The diffractive optical component is a holographic diffuser.

4. The fiber-optic bundle-coupled ultraviolet laser ablation system according to claim 1, characterized in that, The light-diffusing component includes: A microlens group is disposed in the output optical path of the laser to perform beam flat-top shaping of the laser beam to obtain a shaped beam; A focusing lens is disposed in the outgoing light path of the shaping beam to superimpose the shaping beam and obtain the target light spot.

5. The fiber-optic bundled ultraviolet laser ablation system according to claim 4, characterized in that, The focusing lens is a plano-convex lens or a biconvex lens.

6. The fiber-optic bundle-coupled ultraviolet laser ablation system according to claim 1, characterized in that, The fiber optic bundler assembly includes: a protective sleeve; The protective sleeve covers the surface of the large-core quartz optical fiber.

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