Light diffusion device

Abstract

Provided is a light diffusion device which can irradiate light in a direction inclined with respect to the axial direction of a light transmission cable, and which has excellent degree of freedom in material selection for the desire of a device user, such as bioaffinity, cost, operability, and the like. This light diffusion device (1) for photoimmunotherapy or photodynamic therapy is provided with: a light transmission cable (10) that transmits light emitted by a laser oscillator and emits the transmitted light from an emission surface (12) of a tip section (11); a reflection member (30) having a refraction surface (31) that refracts the light emitted from the emission surface (12); and a resin tubular member (20) into which the optical transmission cable (10) and the reflective member (30) are inserted. Furthermore, the refracting surface (31) is disposed so as to be inclined with respect to the axial direction (X) of the optical transmission cable (10) at a position within the tubular member (20) at a predetermined distance from the emission surface (12), and emits the laser light (L) emitted from the emission surface (12) so as to be inclined with respect to the axial direction (X) of the optical transmission cable (10) at a predetermined angle or more.

Description

Technical Field

[0001] The invention relates to a light diffusion device for photoimmunotherapy or photodynamic therapy. Background Art

[0002] As a conventional light diffusion device, there is known a device comprising: an optical transmission cable having an optical transmission path for transmitting light emitted by a light source; and a lens provided at a front end portion of the optical transmission cable; and the device irradiates light emitted from the optical transmission cable in a predetermined direction via the lens (for example, see Patent Document 1). The light diffusion device is used, for example, in photoimmunotherapy and photodynamic therapy performed as treatments for cancer, to insert the front end side of the optical transmission cable into the human body and irradiate light on a drug that is administered to the human body and reaches cancer cells.

[0003] [Prior Technical Literature]

[0004] (Patent Document)

[0005] Patent Document 1: Japanese Patent No. 4659137 Summary of the invention

[0006] [Problems to be solved by the invention]

[0007] In photoimmunotherapy, it is necessary to irradiate light while the front end side of the optical transmission cable is inserted into the human body or positioned near the surface of the tumor. In the case of organs such as the intestine or esophagus, cancer cells that are the irradiation target are mostly present on the side of the organ tube, and it is important to irradiate the light efficiently at an angle relative to the axial direction of the optical transmission cable. In light diffusion devices, the part that refracts light and the front end side of the optical transmission cable are mostly covered and fixed with metal or quartz parts. However, in photoimmunotherapy and photodynamic therapy, since the treatment site is limited by the angle of the emitted light, the structure for irradiating light toward the part that is the irradiation target requires a material structure with a higher degree of freedom in terms of biocompatibility, cost, operability, and other device users' expectations.

[0008] An object of the present invention is to provide a light diffusion device that can irradiate light in a direction inclined relative to the axial direction of an optical transmission cable and has excellent freedom in selecting materials in accordance with the device user's expectations such as biocompatibility, cost, and operability.

[0009] [Technical means to solve the problem]

[0010] (1) A light diffusion device for photoimmunotherapy or photodynamic therapy comprises: an optical transmission cable for transmitting light emitted by a light source and emitting the transmitted light from an exit surface at a front end; a reflective component having a refractive surface for refracting light emitted from the exit surface; and a tubular component made of resin for inserting the optical transmission cable and the reflective component; and the refractive surface is arranged in the tubular component at a position at a predetermined distance from the exit surface in a manner inclined relative to the axial direction of the optical transmission cable, so that the light emitted from the exit surface is emitted at an angle greater than a predetermined angle relative to the axial direction of the optical transmission cable.

[0011] (2) The light diffuser according to (1), wherein the reflective member is a rod-shaped member made of quartz or silicon and is arranged in the tubular member with a gap between the optical transmission cable and the rod-shaped member, and the refractive surface is formed at an end of the rod-shaped member on the optical transmission cable side.

[0012] (3) The light diffuser according to (1) or (2), wherein a metal is vapor-deposited on the refractive surface.

[0013] (4) A light diffusion device according to any one of (1) to (3), wherein the optical transmission cable is a plastic fiber having a core with an outer diameter of 500 µm or more and a resin cladding formed on the outer periphery of the core, and the outer diameter of the refractive surface observed from the axial direction of the optical transmission cable is larger than the outer diameter of the core.

[0014] (5) The light diffuser according to any one of (1) to (4), wherein the irregularities of the surface of the refractive surface on which light is incident are equal to or smaller than the wavelength of light generated from the light source.

[0015] (6) The light diffusion device according to any one of (1) to (5), wherein the emission surface of the light transmission cable is inclined with respect to an axial direction of the light transmission cable.

[0016] (7) The light diffuser according to (6), wherein the emission surface is inclined with respect to the axial direction of the optical transmission cable so as to face the refractive surface substantially in parallel.

[0017] (8) The light diffuser according to any one of (1) to (7), wherein the refractive surface is formed in a curved surface shape that is recessed relative to the emission surface.

[0018] (Effects of the Invention)

[0019] According to the present invention, a light diffuser can be provided which can irradiate light in a direction inclined with respect to the axial direction of an optical transmission cable and has excellent freedom in selecting materials in accordance with the user's requirements of the device, such as biocompatibility, cost, and operability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a side view schematically showing the appearance of the light diffuser according to the first embodiment of the present invention.

[0021] Figure 2 This is a diagram schematically showing the light diffuser according to the first embodiment of the present invention, and is a side view of the light diffuser that irradiates laser light mainly to the side.

[0022] Figure 3 This is a diagram schematically showing a light diffuser according to the first embodiment of the present invention, and is a side view of the light diffuser that irradiates laser light mainly backward.

[0023] Figure 4 It is a side view schematically showing a light diffuser according to a second embodiment of the present invention.

[0024] Figure 5 FIG. 1 is a side view schematically showing a light diffuser according to a third embodiment of the present invention.

[0025] Figure 6 It is a side view schematically showing a light diffuser according to a fourth embodiment of the present invention.

[0026] Figure 7 It is a side view schematically showing the appearance of a light diffuser according to a fifth embodiment of the present invention.

[0027] Figure 8 It is a side view schematically showing a light diffuser according to a fifth embodiment of the present invention. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the present invention is not limited to the following embodiments. In addition, the figures referred to in the following description only schematically show shapes, sizes and positional relationships to the extent that the present disclosure can be understood. That is, the present invention is not limited to the shapes, sizes and positional relationships illustrated in the figures.

[0029] <First embodiment>

[0030] Reference Figure 1 and Figure 2 , a light diffuser 1 according to a first embodiment of the present invention will be described. Figure 1 and Figure 2 It is a side view of the light diffuser 1 . Figure 1 The external appearance of the front end side of the light diffuser 1 is shown. Figure 2 2 is a side view of the front end of the light diffuser 1 showing the structure inside the tubular member 20. Figure 2 In FIG. 1 , the tubular member 20 is shown by a two-dot chain line.

[0031] The light diffuser 1 of this embodiment is mounted on a medical device for performing photoimmunotherapy, which is one of the treatment methods for cancer. Photoimmunotherapy treats cancer by administering the following agent, i.e., an agent composed of an antibody that binds to cancer cells and a substance that reacts with light, to the human body, and irradiating the agent bound to cancer cells with laser light L to destroy the cancer cells. The light diffuser 1 is used, for example, in a state where the front end is exposed to the outside when inserted into a pipeline provided in an endoscope. In addition, the present invention can also be used for photodynamic therapy, and is not limited to photoimmunotherapy.

[0032] The light diffusion device 1 is as follows Figure 1 and Figure 2 As shown, the optical transmission device includes a laser oscillator (not shown) as a light source, an optical transmission cable 10 , a tubular member 20 , and a rod-shaped member 30 as a reflecting member.

[0033] The laser oscillator has a semiconductor laser, and energizes the semiconductor laser to cause laser oscillation, thereby generating laser light L. The laser oscillator generates red laser light L having a wavelength of 600 nm to 700 nm. The laser light L generated by the laser oscillator uses a continuous wave.

[0034] The optical transmission cable 10 is an optical fiber cable having an optical transmission path that transmits laser light L emitted by a laser oscillator. The laser oscillator is arranged on the base end side of the optical transmission cable 10, and a rod-shaped member 30 is provided on the front end 11 side. The optical transmission cable 10 transmits through the optical transmission path, and emits the laser light L generated in the laser oscillator from the emission surface 12 at the front end 11 toward the rod-shaped member 30. The emission surface 12 of this embodiment is a surface perpendicular to the axial direction X of the optical transmission cable 10.

[0035] The optical transmission cable 10 of the present embodiment is a plastic fiber having a core (not shown) and a resin cladding (not shown) formed on the outer periphery of the core. Examples of the resin forming the cladding include polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF). The outer diameter d1 of the core of the optical transmission cable 10 is preferably greater than 500 µm. In the present embodiment, the outer diameter of the core is 500 µm. In the present embodiment, the exit surface 12 of the optical transmission cable 10 is the surface of the core at the front end 11. The core preferably has an outer diameter size corresponding to a multimode fiber. The optical transmission cable 10 of the present embodiment is a multimode fiber, such as Figure 2As shown, laser light L is emitted from multiple locations of the exit surface 12. In addition, the optical transmission cable 10 of the present embodiment is a single-core optical fiber, but it can also be a multi-core optical fiber. Furthermore, regarding the shape of the core, when viewed from the axial direction X of the optical transmission cable 10, in addition to a perfect circle, it can also be an ellipse or a rectangle. In addition, the optical transmission cable 10 can also be an optical fiber composed of a quartz-based material.

[0036] The tubular member 20 is cylindrical and is a resin hose. The resin hose mentioned here includes both hoses composed only of resin and hoses mainly composed of resin. The tubular member 20 accommodates a part of the optical transmission cable 10 and the rod-shaped member 30 inside. The tubular member 20 is configured to be able to reduce in diameter. In this embodiment, the optical transmission cable 10 is inserted into the tubular member 20 in such a manner that at least the front end portion 11 side is located inside the tubular member 20. Figure 1 As shown, the optical transmission cable 10 is accommodated in the tubular member 20 in a state extending in the axial direction of the tubular member 20. The resin forming the tubular member 20 preferably has a light transmittance of 50% or more. Examples of the resin forming the tubular member 20 include polyimide, FEP (tetrafluoroethylene-hexafluoropropylene copolymer), acrylic resin, and the like.

[0037] The rod-shaped member 30 is made of quartz and is accommodated in the tubular member 20. The quartz rod-shaped member 30 mentioned here includes both the rod-shaped member 30 composed only of quartz and the rod-shaped member 30 mainly composed of quartz. Specifically, the rod-shaped member 30 is accommodated in the tubular member 20 with a gap between the optical transmission cable 10 and the rod-shaped member 30 extending in the axial direction of the tubular member 20. In the present embodiment, the rod-shaped member 30 is arranged substantially coaxially with the optical transmission cable 10 in the tubular member 20. In addition, the rod-shaped member 30 may be accommodated in the tubular member 20 as a whole without being exposed to the outside. For example, the optical transmission cable 10 and the rod-shaped member 30 are fixed in the tubular member 20 by tightening them with the radially inward force generated by the tubular member 20 (forming a so-called interference fit state) by making the outer diameter larger than the inner diameter of the tubular member 20. In addition, the rod-shaped member 30 may also be made of silicon. The rod-shaped member 30 made of silicon mentioned here includes both the rod-shaped member 30 composed only of silicon and the rod-shaped member 30 mainly composed of silicon.

[0038] A refractive surface 31 is formed at the end of the rod-shaped member 30 on the optical transmission cable 10 side. The refractive surface 31 is an inclined surface made of quartz formed by cutting the rod-shaped member 30 at an inclination relative to the axial direction. The refractive surface 31 made of quartz mentioned here includes both a refractive surface 31 composed only of quartz and a refractive surface 31 mainly composed of quartz. The refractive surface 31 is arranged in a manner opposite to the emission surface 12 in the tubular member 20 and inclined relative to the axial direction X of the optical transmission cable 10. In addition, the refractive surface 31 may also be made of silicon. The refractive surface 31 made of silicon mentioned here includes both a refractive surface 31 composed only of silicon and a refractive surface 31 mainly composed of silicon.

[0039] like Figure 2 As shown, the refractive surface 31 emits the laser light L emitted from the emission surface 12 at the front end portion 11 of the optical transmission cable 10 to the outside of the tubular member 20 in a manner inclined at a predetermined angle or more relative to the axial direction X of the optical transmission cable 10. Figure 2 As shown in FIG. 1 , the refractive surface 31 refracts each laser light L emitted from multiple locations of the emission surface 12 along the axial direction X of the optical transmission cable 10, and emits it to the side of the tubular member 20. For example, the laser light L refracted by the refractive surface 31 passes through the tubular member 20, is emitted in a direction inclined with respect to the insertion direction of the optical transmission cable 10, and is irradiated to cancer cells or the like existing on the surface of the organ. In addition, for example, Figure 3 As shown, compared with Figure 2 The refractive surface 31 shown in FIG. 1 is set to be inclined closer to vertical with respect to the axial direction X of the optical transmission cable 10. Figure 3 As shown, the laser light L can be irradiated backward from the refractive surface 31. In addition, the axial direction X of the optical transmission cable 10 in this specification refers to the axial direction of the optical transmission cable 10 at the front end portion 11.

[0040] like Figure 2 As shown, the refractive surface 31 of the present embodiment is formed in a flat shape as a whole. The surface roughness of the refractive surface 31 on which the laser light L is incident is preferably less than the wavelength of the laser light L generated from the laser oscillator. For example, by mirror-polishing the refractive surface 31, the roughness less than the wavelength of the laser light L can be achieved. In addition, a metal 32 is vapor-deposited on the refractive surface 31 of the present embodiment. Examples of the metal 32 vapor-deposited on the refractive surface 31 include gold, silver, aluminum, and the like.

[0041] In addition, if Figure 2As shown, the outer diameter d2 of the rod-shaped member 30 is larger than the outer diameter d1 of the core of the optical transmission cable 10. That is, the outer diameter of the refractive surface 31 observed from the axial direction X of the optical transmission cable 10 is larger than the outer diameter d1 of the core. With this structure, since the refractive surface 31 receiving the laser light L emitted from the optical transmission cable 10 is larger than the emission surface 12, the positional deviation of the refractive surface 31 relative to the optical transmission cable 10 can be allowed.

[0042] In addition, the refractive surface 31 is arranged in the tubular member 20 at a position at a predetermined distance from the exit surface 12. The distance between the exit surface 12 and the refractive surface 31 is preferably in the range of 0.5 mm to 1 mm. Between the exit surface 12 and the refractive surface 31, there exists a medium having a refractive index different from that of both the exit surface 12 and the refractive surface 31. For example, in the present embodiment, between the exit surface 12 and the refractive surface 31, there exists only the space 21 as a medium having a different refractive index. In addition, a lens having a refractive index different from that of both the exit surface 12 and the refractive surface 31 and in contact with both the exit surface 12 and the refractive surface 31 may be sandwiched between the exit surface 12 and the refractive surface 31 in a manner that fills the space 21.

[0043] Here, in photoimmunotherapy and photodynamic therapy, a laser with an output of about 0.5 W to 2.0 W is used, so the heat generated by the tubular component 20 through which the laser L from the optical transmission cable 10 passes is relatively small. Therefore, the heat resistance required for the component is relatively low, and as the material of the tubular component 20, a resin material with better biocompatibility can be used instead of a material such as metal or quartz. In addition, in photoimmunotherapy and photodynamic therapy, the following optical transmission cable 10 is mainly used, and the optical transmission cable 10 is a multimode fiber with a relatively large core outer diameter d1 of about 500 µm. Therefore, even if the resin is deformed, such heat is applied to the tubular component 20, and a relative position shift of several µm between the exit surface 12 and the refractive surface 13 occurs, it is not easy to produce an optical effect due to the relative position shift. Therefore, in the light diffusion device 1 of the present embodiment, a resin tubular component 20 suitable for the use of photoimmunotherapy or photodynamic therapy is used.

[0044] <Second embodiment>

[0045] Next, refer to Figure 4 , a light diffuser 1A according to a second embodiment will be described. Figure 4 It is a side view showing a light diffuser 1A according to the second embodiment. Figure 4 2 is a side view of the front end of the light diffuser 1A, which also shows the structure inside the tubular member 20. Figure 4In the following description of the second embodiment, the corresponding symbols are given to the structures corresponding to the first embodiment with the same regularity. The description thereof may be omitted or quoted.

[0046] The light diffuser 1A of this embodiment includes a laser oscillator (not shown), an optical transmission cable 10, a rod-shaped member 30, and a tubular member 20. The light diffuser 1A of this embodiment is different from the light diffuser 1 of the first embodiment mainly in the structure of the tubular member 20A.

[0047] The tubular member 20A has an opening 22 formed on its outer circumference. Specifically, the opening 22 is formed at a portion of the outer circumference of the tubular member 20A that faces the refractive surface 31. With this structure, since the tubular member 20 is not present on the optical path of the laser light L emitted from the emission surface 12 via the refractive surface 31, it is possible to irradiate a stronger laser light L to the outside without passing through the tubular member 20.

[0048] <Third embodiment>

[0049] Next, refer to Figure 5 , a light diffuser 1B according to a third embodiment will be described. Figure 5 It is a side view showing a light diffuser 1B according to the third embodiment. Figure 5 2 is a side view of the front end of the light diffuser 1B, which also shows the structure inside the tubular member 20. Figure 5 In FIG. 1 , the tubular member 20 is shown by a double-dashed line. Figure 5 In order to facilitate reading of the figure, some lines are omitted. In addition, in the following description of the third embodiment, the corresponding symbols with the same regularity are attached to the structures corresponding to the above-mentioned first embodiment. Sometimes the description thereof is omitted or quoted.

[0050] The light diffuser 1B of this embodiment includes a laser oscillator (not shown), an optical transmission cable 10 , a rod-shaped member 30B as a reflective member, and a tubular member 20 . The light diffuser 1B of this embodiment is different from the light diffuser 1 of the first embodiment mainly in the structure of the rod-shaped member 30 .

[0051] The rod-shaped member 30B has a refractive surface 31B formed at the end portion on the optical transmission cable 10 side. The refractive surface 31B has a shape different from the refractive surface 31A of the rod-shaped member 30A of the first embodiment. Figure 5As shown, the refractive surface 31A is formed into a curved surface that is concave relative to the exit surface 12 of the optical transmission cable 10. The curvature radius of the refractive surface 31A is preferably 1200 μm. By adjusting the curvature radius of the refractive surface 31A, the laser light L emitted from the exit surface 12 can be not only diffused but also converged. For example, Figure 5 As shown, by the structure of the curved refractive surface 31A recessed relative to the emission surface 12 , the laser light L emitted from the emission surface 12 can be emitted uniformly as a whole.

[0052] <Fourth embodiment>

[0053] Next, refer to Figure 6 , a light diffuser 1C according to a fourth embodiment will be described. Figure 6 It is a side view showing a light diffuser 1C according to a fourth embodiment. Figure 6 2 is a side view of the front end of the light diffuser 1C, which also shows the structure inside the tubular member 20. Figure 6 In the following description of the fourth embodiment, the tubular member 20 is shown by a two-dot chain line. In addition, in the description of the fourth embodiment below, the corresponding symbols having the same regularity are attached to the corresponding structures of the first embodiment. The description thereof may be omitted or quoted.

[0054] The light diffuser 1C of this embodiment includes a laser oscillator (not shown), an optical transmission cable 10C, a tubular member 20, and a rod-shaped member 30. The light diffuser 1C of this embodiment is different from the light diffuser 1 of the first embodiment mainly in the structure of the front end portion 11C of the optical transmission cable 10C.

[0055] The emission surface 12C of the optical transmission cable 10C of the present embodiment is formed by cutting the front end portion 11C obliquely with respect to the axial direction X of the optical transmission cable 10C. That is, the emission surface 12C is inclined with respect to the axial direction X of the optical transmission cable 10C. Figure 6 As shown in FIG. 1 , the laser light L can be further diffused and then emitted from the emission surface 12C. Figure 6 As shown, the optical transmission cable 10C is inclined with respect to the axial direction X of the optical transmission cable 10 so as to face the refractive surface 31 substantially in parallel. Thus, the optical transmission cable 10C can be brought close to the refractive surface 31, and the laser light L that is not refracted but transmitted by the refractive surface 31 can be reduced.

[0056] <Fifth embodiment>

[0057] Next, refer to Figure 7 , a light diffuser 1D according to a fifth embodiment will be described. Figure 7 It is a side view showing the appearance of the front end side of the light diffuser 1D according to the fifth embodiment. Figure 8It is a longitudinal cross-sectional view of the front end side of the light diffuser 1D, which also shows the structure in the tubular member 20D. In the following description of the fifth embodiment, the structures corresponding to the first embodiment are denoted by the same regularity and corresponding symbols. The description thereof may be omitted or quoted.

[0058] The light diffuser 1D of the present embodiment includes a laser oscillator (not shown), an optical transmission cable 10, a tubular member 20D, a rod-shaped member 30, and an intervening member 40. The light diffuser 1D of the present embodiment is different from the light diffuser 1 of the first embodiment mainly in that the light diffuser 1D further includes an intervening member 40 and in the structure of the tubular member 20D.

[0059] The tubular member 20D of this embodiment is cylindrical and is a resin hose. The difference between the tubular member 20 of the first embodiment and the tubular member 20 is that the inner diameter of the tubular member 20D is slightly smaller than the outer diameter of the rod-shaped member 30 and larger than the optical transmission cable 10. The rod-shaped member 30 is accommodated in the tubular member 20D in such a manner that the outer peripheral surface is in close contact with the inner peripheral surface of the tubular member 20. On the other hand, the rod-shaped member 30 is accommodated in the tubular member 20D in a state where a gap is left between the outer peripheral surface and the inner peripheral surface of the tubular member 20D.

[0060] The interposing member 40 is a member made of a resin having a low refractive index. The interposing member 40 is arranged along the optical transmission cable 10 in the tubular member 20D, and fills the gap between the outer peripheral surface of the optical transmission cable 10 and the inner peripheral surface of the tubular member 20D. As the resin forming the interposing member 40, for example, acrylic resin can be cited. In addition, the interposing member 40 can be a layer covering the outer peripheral surface of the optical transmission cable 10, or an adhesive bonding the outer peripheral surface of the optical transmission cable 10 and the inner peripheral surface of the tubular member 20D.

[0061] According to the above-described embodiment, the following effects are achieved.

[0062] The light diffusion device 1 to 1C for photoimmunotherapy or photodynamic therapy of the present embodiment comprises: an optical transmission cable 10 that transmits laser light L emitted by a laser oscillator and emits the transmitted laser light L from an emission surface 12 of a front end portion 11; a reflective member having a refractive surface 31 that refracts light emitted from the emission surface 12; and a resin tubular member 20 into which the optical transmission cable 10 and the reflective member are inserted; the refractive surface 31 is arranged in a manner inclined with respect to the axial direction X of the optical transmission cable 10 at a predetermined distance from the emission surface 12 in the tubular member 20, and the laser light L emitted from the emission surface 12 is emitted with an inclination of a predetermined angle or more with respect to the axial direction X of the optical transmission cable 10. Thus, the laser light L emitted from the optical transmission cable 10 can be efficiently irradiated in a direction inclined with respect to the insertion direction of the optical transmission cable 10 via the refractive surface 31. In addition, when using photoimmunotherapy or photodynamic therapy, the front end portion 11 of the optical transmission cable 10 and the refractive surface 31 on the front end side of the light diffusion device 1 exposed to the outside from the endoscope are arranged in the resin tubular member 20. As a result, the relatively hard optical transmission cable 10 and the quartz refractive surface 31 can be prevented from contacting the organ tube in the body, so the biocompatibility is excellent. In addition, in addition to the biocompatibility, the freedom of material selection is excellent in terms of cost, operability, etc., the user's expectations.

[0063] In the light diffusers 1 to 1C of the present embodiment, the reflective member is a rod-shaped member 30 made of quartz or silicon and is disposed in the tubular member 20 with a gap between the optical transmission cable 10 and the refractive surface 31 is formed at the end of the rod-shaped member 30 on the optical transmission cable 10 side. Thus, the light diffuser 1 can be manufactured more simply.

[0064] In the light diffusers 1 to 1C of the present embodiment, metal is deposited on the refractive surface 31. This allows light to be refracted more efficiently.

[0065] In the light diffusion devices 1 to 1C of the present embodiment, the optical transmission cable 10 is a plastic fiber having a core with an outer diameter of 500 µm or more and a resin cladding formed on the outer periphery of the core, and the outer diameter of the refractive surface 31 observed from the axial direction X of the optical transmission cable 10 is larger than the outer diameter of the core. Thus, the outer diameter of the refractive surface 31 is larger than the outer diameter d1 of the core 13, so that the tolerance of the relative position deviation of the refractive surface 31 with respect to the optical transmission cable 10 can be increased.

[0066] In the light diffusers 1 to 1C of the present embodiment, the surface irregularities of the refractive surface 31 on which the light is incident are smaller than the wavelength of the light generated by the laser oscillator. Thus, the surface irregularities of the refractive surface 31 on which the laser light L is incident are small, so that the heat generated by the laser light L at the refractive surface 31 during irradiation can be suppressed.

[0067] In the light diffuser 1C of the present embodiment, the emission surface 12C of the optical transmission cable 10C is inclined with respect to the axial direction X of the optical transmission cable 10C. Thus, the emission surface 12 of the optical transmission cable 10 is inclined, so that the light emitted from the optical transmission cable 10 can be further diffused.

[0068] In the light diffuser 1C of the present embodiment, the emission surface 12C is inclined with respect to the axial direction X of the optical transmission cable 10C so as to face the refractive surface 31 substantially in parallel. Thus, the emission surface 12C of the optical transmission cable 10 can be brought closer to the refractive surface 31 of the rod-shaped member 30, and the laser light L that is not refracted at the refractive surface 31 but is transmitted can be reduced.

[0069] In the light diffuser 1B of the present embodiment, the refractive surface 31B is formed into a curved surface that is recessed relative to the emission surface 12. Thus, the laser light L emitted from the emission surface 12 of the optical transmission cable 10 can be tilted and emitted uniformly as a whole by the refractive surface 31B.

[0070] As mentioned above, although embodiment of this invention was demonstrated, this invention is not limited to the said embodiment, It can change suitably.

[0071] Reference numerals

[0072] 1, 1A, 1B, 1C, 1D Light diffusion device

[0073] 10.10C optical transmission cable

[0074] 11 Front end

[0075] 12 exit surface

[0076] 20, 20D Tubular Parts

[0077] 30, 30B Rod-shaped parts (reflective parts)

[0078] 31, 31B Refraction surface

[0079] Axial direction of X-ray transmission cable

Claims

1. A light diffusion device for photoimmunotherapy or photodynamic therapy, comprising: An optical transmission cable transmits light emitted by a light source and emits the transmitted light from an emission surface of a front end portion; a reflective member having a refractive surface for refracting light emitted from the aforementioned emission surface; and a tubular member made of resin into which the optical transmission cable and the reflective member are inserted; and The refractive surface is arranged in a position within the tubular member at a predetermined distance from the emission surface so as to be inclined relative to the axial direction of the optical transmission cable, so that the light emitted from the emission surface is emitted at an angle greater than a predetermined angle relative to the axial direction of the optical transmission cable.

2. The light diffusion device according to claim 1, in, The reflective member is a rod-shaped member made of quartz or silicon and is arranged in the tubular member with a gap between it and the optical transmission cable. The refractive surface is formed at an end portion of the rod-shaped member on the optical transmission cable side.

3. The light diffusion device according to claim 1, in, Metal is evaporated on the refractive surface.

4. The light diffusion device according to claim 1, in, The optical transmission cable is a plastic fiber having a core with an outer diameter of 500 µm or more and a resin cladding formed on the outer periphery of the core. An outer diameter of the refractive surface viewed in the axial direction of the optical transmission cable is larger than an outer diameter of the core.

5. The light diffusion device according to any one of claims 1 to 4, in, The surface irregularities of the refractive surface on which light is incident are smaller than the wavelength of light generated from the light source.

6. The light diffusion device according to claim 1, in, The emission surface of the optical transmission cable is inclined relative to the axial direction of the optical transmission cable.

7. The light diffusion device according to claim 6, in, The emission surface is inclined with respect to the axial direction of the optical transmission cable so as to face the refractive surface substantially in parallel.

8. The light diffusion device according to claim 1, in, The refractive surface is formed in a curved surface shape that is concave relative to the emitting surface.

Images