Peripheral light emitting linear light guide and its manufacturing method

Abstract

To provide a peripheral surface light emission linear light guide body capable of enhancing uniformity of intensity of radiated light, a manufacturing method thereof.SOLUTION: A peripheral surface light emission linear light guide body 3 includes: an optical fiber 4 in which a core 41 is exposed from a clad 42 at one end in a longitudinal direction; and a light scattering member 5 for covering an outer peripheral surface 41a of the core 41 over a predetermined length range E including a tip part 411 of the core 41 of the part exposed from the clad 42. In the light scattering member 5, light scattering particles 500 are dispersed and mixed in a light transmitting base material 50, the amount of the light scattering particles 500 in the outer periphery of the core 41 is larger at the end part on the tip side of the core 41 than at the end part on a clad 42 side, and a reflection film 7 is formed on an end surface 411a of the tip part 411 of the core 41. In a manufacturing method of the peripheral surface light emission linear light guide body 3, the light scattering member 5 is formed over the predetermined length range E including the tip part 411 of the core 41 after forming the reflection film 7 on the end surface 411a of the core 41 of the optical fiber 4 in which the core 41 is exposed from the clad 42.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a peripheral light-emitting linear light guide provided with an optical fiber and a light scattering member, and a method for manufacturing the same. [Background technology]

[0002] Conventionally, catheter treatment has been performed in which an optical fiber catheter equipped with an optical fiber is inserted into a hollow organ such as the esophagus or intestines of the human body, or into a blood vessel or the heart, and the affected area is treated using light emitted from the optical fiber catheter (see, for example, Patent Document 1).

[0003] The medical lighting system of Patent Document 1 includes a laser light source, an optical waveguide (optical fiber) that guides the laser light emitted from the laser light source, and a diffuser element attached to the distal end of the optical waveguide. The diffuser element has a diffuser substrate made of a transparent material such as quartz glass, and the diffuser substrate contains a scattering element that scatters the light. The diffuser element is cylindrical with a diameter larger than that of the optical waveguide, and the laser light guided by the optical waveguide enters one end of the diffuser element in the longitudinal direction. The laser light that enters the diffuser element is scattered by the scattering element and irradiates the treatment target area. The other end of the diffuser element is provided with a reflective surface that reflects the laser light that has passed through the diffuser substrate in the longitudinal direction back to the diffuser element. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2020-534956 Summary of the Invention [Problem to be solved by the invention]

[0005] In the optical fiber catheter described above, it is desirable that the intensity of the light emitted laterally be highly uniform in the longitudinal direction in order to improve the accuracy and safety of treatment. However, for example, in the case of the one described in Patent Document 1, if the scattering elements are uniformly arranged along the longitudinal direction of the diffuser substrate, the intensity of the light emitted laterally will vary depending on the location in the longitudinal direction.

[0006] The present invention has been made in consideration of the above circumstances, and its purpose is to provide a peripheral light-emitting linear light guide that can improve the uniformity of the intensity of emitted light, and a method for manufacturing the same. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides a peripheral light-emitting linear light guide comprising an optical fiber in which the core is exposed from the cladding at one longitudinal end, and a light-scattering member covering the outer surface of the core over a predetermined length range including the tip of the core in the portion exposed from the cladding, wherein the light-scattering member has light-scattering particles dispersed and mixed in a light-transmitting base material, the amount of light-scattering particles around the outer periphery of the core is greater at the end toward the tip of the core than at the end toward the cladding, and a reflective film is formed on the end surface of the tip of the core.

[0008] In addition, for the purpose of solving the above-mentioned problems, the present invention provides a method for manufacturing a peripheral light-emitting linear light guide, comprising: an optical fiber processing step of removing the cladding at one longitudinal end of an optical fiber having a core and a cladding covering the outer surface of the core to expose the core; a reflective film forming step of forming a reflective film on the end surface of the tip of the core in the portion exposed from the cladding; and a light-scattering member forming step of forming a light-scattering member in which light-scattering particles are dispersed and mixed in a light-transmitting base material over a predetermined length range including the tip of the core, wherein in the light-scattering member forming step, the light-scattering member is formed so that the amount of light-scattering particles around the outer periphery of the core is greater at the end toward the tip of the core than at the end toward the cladding. [Effects of the Invention]

[0009] According to the peripheral light-emitting linear light guide and the manufacturing method thereof of the present invention, it is possible to improve the uniformity of the intensity of the emitted light. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram showing a treatment device having a catheter configured using a peripheral light-emitting linear light guide according to an embodiment of the present invention, together with a patient to be treated. [Figure 2] FIG. 1 is a schematic diagram showing the distal end of a catheter inserted into a patient's body. [Figure 3] 1A is a perspective view showing one end of a peripheral surface-emitting linear light-guiding body, FIG. 1B is a cross-sectional view of the peripheral surface-emitting linear light-guiding body along its axial direction, and FIG. 1C is a cross-sectional view of the distal end of the peripheral surface-emitting linear light-guiding body along its axial direction. [Figure 4] 1(a) to 1(d) are explanatory diagrams showing the optical fiber processing steps. [Figure 5] 10(a) to 10(e) are explanatory views showing the state in which first to fourth light scattering layers and a protective coating layer are formed in order around the outer periphery of the exposed core. [Figure 6] 1(a) and 1(b) are schematic diagrams showing the configuration of a light-scattering layer forming apparatus for forming the first to fourth light-scattering layers. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Embodiment Mode] 1 is a schematic diagram showing a treatment device using a peripheral light-emitting linear light guide according to an embodiment of the present invention as a catheter, together with a patient to be treated. The treatment device 1 has a main body 2 and a peripheral light-emitting linear light guide 3, and the distal end of the peripheral light-emitting linear light guide 3 is inserted into the body of the patient P. The main body 2 has a light source 21 that emits laser light, and the laser light generated by the light source 21 is incident on the proximal end of the peripheral light-emitting linear light guide 3.

[0012] <Configuration of peripheral light-emitting linear light guide 3> FIG. 2 is a schematic diagram showing a portion of the peripheral light-emitting linear light guide 3 inserted into the body of a patient P. In FIG. 2, a portion of a blood vessel P1 of the patient P is cut out to show the peripheral light-emitting linear light guide 3 inserted into the blood vessel P1. The laser light Lr scattered and emitted from the peripheral light-emitting linear light guide 3 irradiates the treatment area P2, causing a reaction with a drug that has been previously contained in the treatment area P2. In this way, intravascular laser treatment is performed.

[0013] Fig. 3(a) is a perspective view showing one end of the peripheral surface light-emitting linear light-guiding member 3. Fig. 3(b) is a cross-sectional view of the peripheral surface light-emitting linear light-guiding member 3 along the axial direction. Fig. 3(c) is a cross-sectional view of the tip end of the peripheral surface light-emitting linear light-guiding member 3 along the axial direction.

[0014] The peripheral light-emitting linear light guide 3 includes an optical fiber 4 that guides laser light generated by the light source 21 as propagating light to the treatment area P2, a light scattering member 5 provided at one end of the optical fiber 4, and a protective coating layer 6 that covers the light scattering member 5. The optical fiber 4 has a core 41, a clad 42, and a sheath 43. At one longitudinal end of the optical fiber 4, an outer peripheral surface 42a of the clad 42 is exposed from the sheath 43, and further, an outer peripheral surface 41a of the core 41 is exposed from the clad 42.

[0015] A reflective film 7 that reflects laser light, which is propagated light generated by the light source 21 and propagated through the core 41, is formed on the end surface 411a of the tip 411 of the core 41, which is exposed from the cladding 42. In this embodiment, the reflective film 7 is formed by sputtering. Note that sputtering here refers to a process in which an inert gas such as argon gas is collided with a metal target in a vacuum, and the released atoms or molecules of the target are attached to an object. The metal used as the target for sputtering is preferably gold (Au) or silver (Ag), which easily adheres to the core 41 and has high light reflectivity. The thickness t0 (see FIG. 3(c)) of the reflective film 7 formed by sputtering is, for example, several nm.

[0016] The reflective film 7 is integrally formed with a disk portion 71 that covers the entire end face 411a of the tip portion 411 of the core 41, and a cylindrical portion 72 that covers the outer peripheral surface 41a of the core 41 near the end face 411a. In other words, the reflective film 7 covers the end face 411a of the core 41 as well as a portion of the outer peripheral surface 41a of the core 41. However, it is preferable that the length of the cylindrical portion 72 in the longitudinal direction of the core 41 is as short as possible, and is desirably shorter than the diameter of the end face 411a of the core 41. In this embodiment, the reflective film 7 is made of metal, but this is not limiting, and the reflective film 7 may be made of a dielectric material such as white resin or ceramic.

[0017] Furthermore, the method of forming the reflective film 7 is not limited to sputtering, and it may be formed by, for example, a silver mirror reaction, or by applying and solidifying molten solder. Alternatively, solder may be bonded to the tip 411 of the core 41 by ultrasonic vibration. When the metallic reflective film 7 is formed in this way to a thickness of, for example, 1 μm or more, the heat conduction of the reflective film 7 improves the heat dissipation of the portion that generates heat due to the laser light.

[0018] The light-scattering member 5, together with the reflective film 7, covers the entire circumference of the outer circumferential surface 41a of the core 41 over a predetermined length range E including the tip portion 411 of the core 41 exposed from the clad 42. The axial length of the portion of the core 41 covered by the light-scattering member 5 is, for example, 1 to 5 cm. A part of the core 41 in the longitudinal direction is an uncovered portion 410 that is not covered by either the clad 42 or the light-scattering member 5. The protective coating layer 6 is optically transparent and covers the light-scattering member 5, the uncovered portion 410 of the core 41, and the portion of the clad 42 exposed from the sheath 43.

[0019] In this embodiment, as an example, the core 41 is made of silica glass, and the clad 42 is made of a polymer. The sheath 43 is a fluorine-based resin, more specifically, ETFE (ethylene tetrafluoroethylene copolymer). The diameter of the core 41 is, for example, 200 μm. The refractive index of the core 41 is higher than the refractive index of the clad 42, and light propagating through the core 41 within the clad 42 is totally reflected at the interface with the clad 42. In the portion of the core 41 exposed from the clad 42, light is emitted from the outer peripheral surface 41 a of the core 41.

[0020] The light scattering member 5 scatters and radiates light emitted from the outer peripheral surface 41a of the core 41. The light scattering member 5 has a large number of light scattering particles 500 dispersed and mixed in a light-transmitting substrate 50 having a higher refractive index than the core 41. Here, "dispersed and mixed" means that the light scattering particles 500 are mixed so as to be evenly scattered within the substrate 50, so that the light scattering particles 500 do not aggregate in one part of the substrate 50. In this embodiment, the substrate 50 is made of a thermosetting resin. The light scattering particles 500 are so fine that they cannot be seen with the naked eye, but the size of the light scattering particles 500 is exaggerated in FIG. 3(c).

[0021] Since the refractive index of the substrate 50 is higher than that of the core 41, a high proportion of light traveling from the inside of the core 41 toward the outer peripheral surface 41a enters the light-scattering member 5. In this embodiment, the substrate 50 is a thermosetting silicone resin, and its refractive index is, for example, 1.52. The refractive index of the core 41 is, for example, 1.46. The refractive index of the protective coating layer 6 is the same as or higher than that of the substrate 50.

[0022] The light scattering particles 500 are metal particles that reflect light incident on the light scattering member 5. In this embodiment, rutile titanium oxide (TiO2) is used as the light scattering particles 500. However, the light scattering particles 500 are not limited to this, and may also be aluminum oxide (alumina), or fine metal powder of silver, copper, iron, or an alloy thereof.

[0023] The light-scattering member 5 has a multi-stage structure in which the thickness from the outer peripheral surface 41a of the core 41 gradually increases toward the tip 411 of the core 41. The light-scattering member 5 also has a multi-layer structure made up of multiple light-scattering layers, and the number of multiple light-scattering layers stacked on the outer periphery of the core 41 gradually increases from the end of the predetermined length range E on the clad 42 side toward the tip 411 of the core 41. The thickness of the light-scattering member 5 increases as the number of light-scattering layers overlapping in the radial direction of the core 41 increases. In this embodiment, the light-scattering member 5 has four light-scattering layers, and all four light-scattering layers overlap in the radial direction at the outer periphery of the tip 411 of the core 41. At the end of the light-scattering member 5 on the clad 42 side, only one light-scattering layer is formed on the outer periphery of the core 41.

[0024] Hereinafter, these four light scattering layers will be referred to as, from the inside out, a first light scattering layer 51, a second light scattering layer 52, a third light scattering layer 53, and a fourth light scattering layer 54. In each of the first to fourth light scattering layers 51 to 54, light scattering particles 500 are dispersed and mixed in a substrate 50. The concentration of the light scattering particles 500 relative to the substrate 50 of each of the first to fourth light scattering layers 51 to 54 is, for example, 0 to 200 mg / mL (0 mg or more and 200 mg or less per mL).

[0025] 3(c), the thicknesses t1 to t4 of the first to fourth light scattering layers 51 to 54 in the radial direction of the core 41 are approximately the same. Each of t1 to t4 is, for example, 5 to 10 μm. The thickness t5 of the protective coating layer 6 is, for example, the same as t1 to t4, but may be different from t1 to t4.

[0026] 3(b), when a predetermined length range E of the core 41 covered with the light-scattering member 5 is divided into first to fourth regions E1 to E4 according to the number of layers (four in this embodiment), in the first region E1 closest to the tip of the core 41, first to fourth light-scattering layers 51 to 54 are formed on the outer periphery of the core 41, and in the fourth region E4 closest to the cladding 42, only the fourth light-scattering layer 54 is formed on the outer periphery of the core 41. In the second region E2 adjacent to the first region E1, second to fourth light-scattering layers 52 to 54 are formed on the outer periphery of the core 41, and in the third region E3 adjacent to the fourth region E4, third and fourth light-scattering layers 53 and 54 are formed on the outer periphery of the core 41. The outer periphery surface 41a of the core 41 and the first to fourth light-scattering layers 51 to 54 are in close contact with each other without any gaps.

[0027] Due to this multilayer structure, the thickness of the light-scattering member 5 in the radial direction of the core 41 is greater at the outer periphery of the first region E1 (the end on the tip 411 side of the core 41) than at the outer periphery of the fourth region E4 (the end on the cladding 42 side). Also, the amount of light-scattering particles 500 around the outer periphery of the core 41 is greater at the outer periphery of the first region E1 (the end on the tip 411 side of the core 41) than at the outer periphery of the fourth region E4 (the end on the cladding 42 side).

[0028] The first to fourth light-scattering layers 51 to 54 have different mixing ratios of the light-scattering particles 500 to the substrate 50. In this embodiment, when the concentrations of the light-scattering particles 500 in the first to fourth light-scattering layers 51 to 54 are designated C1 to C4, respectively, the concentration C1 in the first light-scattering layer 51 is, for example, 20 mg / mL, the concentration C2 in the second light-scattering layer 52 is, for example, 10 mg / mL, the concentration C3 in the third light-scattering layer 53 is, for example, 0 mg / mL, and the concentration C4 in the fourth light-scattering layer 54 is, for example, 7 mg / mL. That is, in this embodiment, the concentrations C1 to C4 of the light-scattering particles 500 in the first to fourth light-scattering layers 51 to 54 have a relationship of C1>C2>C4>C3.

[0029] Thus, in this embodiment, the first light scattering layer 51, which has the highest mixing ratio of light scattering particles 500 among the first to fourth light scattering layers 51 to 54, is formed in the first region E1 closest to the tip of the core 41.

[0030] Furthermore, in this embodiment, the concentration C4 of the fourth light-scattering layer 54 formed in contact with the outer peripheral surface 41 a of the core 41 in the fourth region E4 is higher than the concentration C3 of the third light-scattering layer 53 formed in contact with the outer peripheral surface 41 a of the core 41 in the third region E3. This is the result of adjustments being made to improve the uniformity of the intensity of the light emitted from the light-scattering member 5 and to improve the rise of the light intensity at the end of the light-scattering member 5 on the clad 42 side, since a phenomenon was observed in which the intensity of the light emitted from the light-scattering member 5 peaked a short distance in the axial direction from the end of the light-scattering member 5 on the clad 42 side when the concentrations C3 and C4 were the same. Note that in the above example, the concentration C3 of the third light-scattering layer 53 was 0 mg / mL, and the third light-scattering layer 53 did not contain the light-scattering particles 500, but the third light-scattering layer 53 may contain the light-scattering particles 500. However, even in this case, it is desirable that the concentration C3 of the third light scattering layer 53 be lower than the concentration C4 of the fourth light scattering layer .

[0031] Although the case where the number of layers of the light-scattering member 5 is four has been described here, the number of layers of the light-scattering member 5 is not limited to four, and may be two, three, or five or more. When the number of layers is n (n is a natural number of two or more) and the axial length range E of the core 41 is divided into n regions according to the number of layers, the number of layers in the region closest to the tip of the core 41 among these n regions is n, and the number of layers in the region closest to the cladding 42 is 1.

[0032] Furthermore, the light-scattering member 5 is not limited to a multilayer structure, and may have a single-layer structure in which the light-scattering particles 500 are mixed uniformly in the base material 50. In this case, by making the thickness of the light-scattering member 5 in the radial direction of the core 41 thicker at the end on the tip portion 411 side of the core 41 than at the end on the clad 42 side, the amount of light-scattering particles 500 around the periphery of the core 41 can be made greater at the end on the tip portion 411 side of the core 41 than at the end on the clad 42 side.

[0033] <Method of manufacturing peripheral light-emitting linear light guide 3> Next, a description will be given of a manufacturing method of the peripheral surface-emitting linear light guide 3. The manufacturing method of the peripheral surface-emitting linear light guide 3 includes an optical fiber processing step of removing the cladding 42 at one longitudinal end of the optical fiber 4 to expose the core 41, a reflective film forming step of forming a reflective film 7 on the end face 411a of the tip portion 411 of the core 41 in the portion exposed from the cladding 42, and a light scattering member forming step of forming a light scattering member 5 so that the amount of light scattering particles 500 around the periphery of the core 41 is greater at the end of the core 41 on the tip portion 411 side than at the end on the cladding 42 side. The light scattering member forming process further includes a preparation step of preparing a liquid material that will become the light scattering member 5 upon hardening, an arrangement step of arranging the optical fiber 4 above the liquid material so that the core 41 protruding from the end of the clad 42 hangs vertically, a movement step of moving the core 41 and the liquid material relative to each other in the vertical direction, moving a portion of the axial direction of the core 41 below the liquid surface of the liquid material, and then lifting the core 41 out of the liquid material, and a hardening step of hardening the liquid material that has adhered to the core 41 by lifting it up.

[0034] 4(a) to 4(d) are explanatory diagrams showing the optical fiber processing step and the reflective coating forming step. FIG. 4(a) shows one end of an optical fiber 4 before processing, which has been cut to a predetermined length by, for example, cleaving. In this state, the outer periphery of the core 41 is covered with a cladding 42, and the outer periphery of the cladding 42 is further covered with a sheath 43. FIG. 4(b) shows the state in which the sheath 43 has been removed over a predetermined length from the axial end, exposing the outer circumferential surface 42a of the cladding 42. FIG. 4(c) shows the state in which the cladding 42, which is exposed from the sheath 43, has been removed over a predetermined length from the axial end, exposing the outer circumferential surface 41a of the core 41. In the reflective coating forming step, as shown in FIG. 4(d), a reflective coating 7 is formed on the tip portion 411 of the core 41, which is exposed from the cladding 42.

[0035] 5(a) to 5(d) are explanatory diagrams showing the state in which first to fourth light-scattering layers 51 to 54 and a protective coating layer 6 are sequentially formed around the periphery of the exposed core 41. As shown in FIGS. 5(a) to 5(d), in the light-scattering member 5, a first light-scattering layer 51 is formed around the periphery of the first region E1 of the core 41, and then a second light-scattering layer 52 is formed around the first light-scattering layer 51 and the periphery of the second region E2 of the core 41. Further thereafter, a third light-scattering layer 53 is formed around the second light-scattering layer 52 and the periphery of the third region E3 of the core 41, and a fourth light-scattering layer 54 is formed around the third light-scattering layer 53 and the periphery of the fourth region E4 of the core 41.

[0036] 6(a) and 6(b) are schematic diagrams showing a light-scattering layer forming apparatus 8 for forming the first to fourth light-scattering layers 51 to 54. In FIGS. 6(a) and 6(b), the up-down direction in the drawings corresponds to the vertical direction. The light-scattering layer forming apparatus 8 includes a base plate 81, a support 82 connected perpendicularly to the base plate 81, an elevator 83 movable in the up-down direction relative to the support 82, a holder 84 for holding the optical fiber 4, and a heater 85 fixed to the support 82.

[0037] The lifting platform 83 is moved up and down relative to the support column 82 by an actuator (not shown). This actuator may be configured to convert the rotation of an electric motor into linear motion using a ball screw or the like. The lifting platform 83 has a support portion 831 that supports the holder 84, and the holder 84 is supported by this support portion 831.

[0038] The holder 84 holds the optical fiber 4 covered with the sheath 43 in the vertical direction over a predetermined length range. As a result, in the arrangement process, the core 41 protruding from the end of the cladding 42 is arranged so as to hang down vertically. The holder 84 moves up and down together with the lifting platform 83 while holding the optical fiber 4.

[0039] The heater 85 has an insertion hole 850 through which the optical fiber 4 is inserted vertically. A cylindrical radiating material 851 that radiates infrared rays is arranged around the insertion hole 850, and the radiating material 851 is heated by a heating wire 852, causing the infrared rays to be radiated into the insertion hole 850. This makes it possible to heat the periphery of the core 41 of the optical fiber 4 evenly from all directions. The radiating material 851 and the heating wire 852 are housed in a case member 853, and the case member 853 is connected to the support 82 by a connecting arm 854.

[0040] In the preparation step, multiple types of liquids (first to fourth liquids 911 to 914) with different mixing ratios of light scattering particles 500 are prepared. The first liquid 911 becomes the first light scattering layer 51 when cured, and the second liquid 912 becomes the second light scattering layer 52 when cured. Furthermore, the third liquid 913 becomes the third light scattering layer 53 when cured, and the fourth liquid 914 becomes the fourth light scattering layer 54 when cured.

[0041] In the first to fourth liquids 911 to 914, a large number of light scattering particles 500 are dispersed and mixed in the liquid base material 50L before it is hardened. The liquid base material 50L is liquid at room temperature before the heating step, and is hardened by being heated by the heater 85 to become the solid base material 50. The concentrations of the light scattering particles 500 in the first to fourth liquids 911 to 914 are concentrations that satisfy the relationship C1>C2>C4>C3 described above.

[0042] The first to fourth liquid materials 911 to 914 are contained in first to fourth containers 921 to 924, respectively. The first to fourth containers 921 to 924 are cup-shaped and open at the top. FIG. 6(a) shows the first to fourth containers 921 to 924 in cross section, illustrating the first to fourth liquid materials 911 to 914 inside them. Also, FIGS. 6(a) and 6(b) show a state in which the second container 922 is placed on the placement surface 81a of the base plate 81, which is below the heater 85.

[0043] When forming the light scattering member 5, the moving step and the curing step are repeated for each of the first to fourth liquid materials 911 to 914. In the present embodiment, since the light scattering member 5 has a four-layer structure, the moving step and the curing step are each repeated four times. The first to fourth liquid materials 911 to 914 are sequentially placed on the placement surface 81a of the base plate 81 after each moving step and curing step.

[0044] In the moving step, the lifting platform 83 is moved downward to move a portion of the core 41 in the axial direction below the liquid surfaces of the first to fourth liquid materials 911 to 914, and then the core 41 is lifted up from the first to fourth liquid materials 911 to 914. The liquid base material 50L has viscosity, and when the lifting platform 73 moves upward, the core 41 is lifted up with the base material 50L adhering to the surrounding area due to its viscosity. Figure 6(a) shows a state in which the core 41 is being lifted up from the liquid surface 912a of the second liquid material 912.

[0045] When the core 41 is pulled up, the lifting platform 83 is pulled up at a slow speed, for example, about 0.02 mm per second, so that the substrate 50L adheres with as uniform a thickness as possible. The speed at which the core 41 is pulled up is preferably 0.1 mm / second or less, and more preferably 0.05 mm / second or less. Figure 6(a) shows a state in which the second liquid material 912 adheres with a uniform thickness to the outer periphery of the first light scattering layer 51 and the second region E2 of the core 41.

[0046] In the curing process, as shown in FIG. 6(b), the lifting platform 83 is raised until the core 41 exposed from the cladding 42 is positioned within the insertion hole 850 of the heater 85, and the first to fourth liquid bodies 911 to 914 that were attached in the moving process are heated and cured by infrared rays emitted from the radiating material 851.

[0047] Then, after forming the first to fourth light scattering layers 51 to 54 on the outer periphery of the core 41, the protective coating layer 6 is formed to obtain the peripheral light-emitting linear light guide 3. The protective coating layer 6 may be formed in the same manner as the first to fourth light scattering layers 51 to 54, for example, or may be formed by a process different from that for the first to fourth light scattering layers 51 to 54.

[0048] (Actions and Effects of the Embodiments) According to the embodiment described above, the light-scattering member 5 has a multi-stage structure in which the thickness gradually increases toward the tip 411 of the core 41, and the amount of light-scattering particles 500 is greater at the end of the core 41 on the tip 411 side than at the end of the core 41 on the cladding 42 side, thereby improving the uniformity of the intensity of light emitted from the light-scattering member 5. Furthermore, in this embodiment, the reflective film 7 is formed on the end face 411a of the tip 411 of the core 41, so that it is possible to prevent damage to the body of the patient P to be treated by the strong light emitted in the axial direction from the tip 411 of the core 41. Furthermore, the light reflected by the reflective film 7 is emitted from the outer peripheral surface 41a of the core 41 and scattered by the light-scattering member 5 to irradiate the treatment area P2, thereby improving the utilization efficiency of the laser light generated by the light source 21 and further improving the uniformity of the intensity of the light emitted from the light-scattering member 5.

[0049] (Summary of the embodiment) Next, the technical ideas grasped from the above-described embodiments will be described by using the reference numerals and the like in the embodiments. However, the reference numerals in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiments.

[0050] [1] A peripheral light-emitting linear light guide (3) comprising: an optical fiber (4) in which a core (41) is exposed from a clad (42) at one longitudinal end; and a light-scattering member (5) covering an outer surface (41a) of the core (41) over a predetermined length range (E) including a tip end (411) of the core (41) exposed from the clad (42), wherein the light-scattering member (5) has light-scattering particles (500) dispersed and mixed in a light-transmitting base material (50), the amount of the light-scattering particles (500) around the outer periphery of the core (41) being greater at the tip end of the core (41) than at the end on the clad (42) side; and a reflective film (7) formed on an end face (411a) of the tip end (411) of the core (41).

[0051] [2] The peripheral light-emitting linear light guide (3) according to [1] above, wherein the light-scattering member (5) is a thermosetting silicone resin having a higher refractive index than the core (41) and light-scattering particles (500) dispersed and mixed therein.

[0052] [3] The peripheral surface light-emitting linear light guide (3) described in [1] or [2] above, wherein the light-scattering member (5) is composed of a plurality of light-scattering layers (51 to 54), and the number of the plurality of light-scattering layers (51 to 54) stacked on the outer periphery of the core (41) gradually increases from the end on the clad (42) side in the predetermined length range (E) toward the tip portion (411).

[0053] [4] The peripheral light-emitting linear light guide (3) according to the above [3], which is dependent on the above [2], wherein the light-scattering particles (500) are made of titanium oxide, and the concentration of the light-scattering particles (500) relative to the silicone resin in each of the plurality of light-scattering layers (51 to 54) is 0 mg or more and 200 mg or less per mL.

[0054] [5] The peripheral light-emitting linear light guide (3) according to any one of [1] to [4] above, wherein the reflective film (7) covers the end face (411a) of the core (41) as well as a part of the outer peripheral surface (41a) of the core (41).

[0055] [6] The peripheral light-emitting linear light guide (3) according to any one of the above [1] to [5], wherein the reflective film (7) is formed by sputtering.

[0056] [7] An optical fiber processing step of removing the clad (42) at one longitudinal end of an optical fiber (4) having a core (41) and a clad (42) covering an outer peripheral surface (41a) of the core (41) to expose the core (41); a reflective film forming step of forming a reflective film (7) on an end face (411a) of a tip end (411) of the core (41) in a portion exposed from the clad (42); and a predetermined area including the tip end (411) of the core (41). a light-scattering member forming step of forming a light-scattering member (5) in which light-scattering particles (500) are dispersed and mixed in a light-transmitting substrate (50) over a length range (E), wherein in the light-scattering member forming step, the light-scattering member (5) is formed so that the amount of the light-scattering particles (500) around the outer periphery of the core (41) is greater at the end on the tip side of the core (41) than at the end on the clad (42) side.

[0057] (Addendum) Although the embodiments of the present invention have been described above, the invention according to the claims is not limited to the embodiments described above. It should be noted that not all of the combinations of features described in the embodiments are necessarily essential to the means for solving the problems of the invention. [Explanation of symbols]

[0058] 3...Circumferential surface emitting linear light guide 4...Optical fiber 41...Core 411...Tip 411a...End face 41a...Outer surface 42... Cladding 5... Light scattering member 50...Base material 500...Light scattering particles 51...first light scattering layer 52...second light scattering layer 53...Third light scattering layer 54...Fourth light scattering layer 7...Reflective film E...Specified length range

Claims

1. an optical fiber having a core exposed from a clad at one end in a longitudinal direction; and a light scattering member covering an outer peripheral surface of the core over a predetermined length range including a tip end of the core exposed from the clad, the light-scattering member is a light-transmitting substrate having light-scattering particles dispersed therein, and is made up of a plurality of light-scattering layers; the number of the plurality of light scattering layers stacked on the outer periphery of the core gradually increases from the end portion on the cladding side to the tip portion in the predetermined length range, the amount of the light scattering particles around the periphery of the core is greater at the tip end of the core than at the cladding end, a reflective film is formed on the end surface of the tip portion of the core; Peripheral light emitting linear light guide.

2. the light scattering member is formed by dispersing and mixing the light scattering particles in a thermosetting silicone resin having a refractive index higher than that of the core; The peripheral light-emitting linear light guide according to claim 1 .

3. the light-scattering particles are made of titanium oxide, a concentration of the light-scattering particles in the silicone resin of each of the plurality of light-scattering layers being 0 mg or more and 200 mg or less per mL; The peripheral light-emitting linear light guide according to claim 2 .

4. the reflective film covers the end face of the core and a part of the outer circumferential surface of the core; The peripheral surface light-emitting linear light guide according to any one of claims 1 to 3.

5. The reflective film is formed by sputtering. The peripheral light-emitting linear light guide according to claim 1 .

6. an optical fiber processing step of removing a cladding at one end in a longitudinal direction of an optical fiber having a core and a cladding covering an outer peripheral surface of the core, thereby exposing the core; a reflective film forming step of forming a reflective film on the end face of the tip of the core in the portion exposed from the cladding; a light-scattering member forming step of forming a light-scattering member in which light-scattering particles are dispersed and mixed in a light-transmitting base material over a predetermined length range including the tip end of the core, In the light scattering member forming step, the light scattering member is formed so that the amount of the light scattering particles around the outer periphery of the core is greater at an end on the tip side of the core than at an end on the cladding side. A method for manufacturing a peripheral light-emitting linear light guide.

Images