Light irradiation device and in-vivo light irradiation assembly using same

Abstract

Provided is a light irradiation device which is small and has heat dissipation and electrical insulation. The light irradiation device includes: a light-emitting element that has a first surface for emitting light having a prescribed wavelength; a support body on which the light-emitting element is mounted; a first insulating layer that covers at least a part of the light-emitting element excluding the first surface; an insulated wire electrically connected to the light-emitting element in a region excluding the first surface; and a case that seals the first surface in a first space.

Description

Light irradiation device and in vivo light irradiation assembly using the same

[0001] The present disclosure relates to a light irradiation device and an in-vivo light irradiation assembly using the same.

[0002] Endoscopes are used for in vivo diagnosis and treatment. When an endoscope is inserted into a body cavity to observe an affected area, it can be configured to introduce illumination light via an optical fiber or to have a light-emitting diode (LED) attached to the tip of the endoscope to emit illumination light. For the latter configuration, a configuration has been proposed in which a portion of the outer casing is used as a heat dissipation member to improve heat dissipation from the light-emitting diode and to reduce the size of the tip (see, for example, Patent Document 1). In this endoscope, a flexible printed circuit board (FPC) with multiple light-emitting diodes (LEDs) arranged in a row is rolled into a cylindrical shape and inserted into the outer casing, and heat from the LEDs is dissipated from the FPC to the outer casing.

[0003] In addition to endoscopic illumination light, light introduced into the body also includes light for treatment. In photoimmunotherapy, which has recently attracted attention, if the affected area is on the surface of the body or shallow below the surface, light of a specific wavelength that reacts with a photosensitizer accumulated in cancer cells is irradiated from the surface of the body. If the affected area is located deep below the surface, laser light is irradiated onto the affected area inside the body via a puncture. An optical fiber is inserted into a blood vessel, digestive tract, or other lumen, and laser light of a specific wavelength is irradiated onto the affected area inside the body from an external light source.

[0004] JP 2008-272298 A

[0005] The configuration using an optical fiber for laser irradiation inside a living body is weak against bending, and the optical loss increases in proportion to the length of the optical fiber. There is a demand for an ultra-compact light source that can be inserted into the body close to the affected area without an optical fiber. One aspect of the present disclosure provides a compact light irradiation device that has heat dissipation and electrical insulation properties.

[0006] In one embodiment, the light irradiation device includes: a light emitting element having a first surface that emits light of a predetermined wavelength; a support on which the light emitting element is mounted; a first insulating layer that covers at least a portion of the light emitting element except for the first surface; an insulated wire that is electrically connected to the light emitting element in an area other than the first surface; and a case that seals the first surface within a first space.

[0007] A compact light-emitting device having heat dissipation and electrical insulation properties can be realized.

[0008] Fig. 1 is a diagram showing an example of an in vivo light irradiation assembly using the light irradiation device of the first embodiment; Fig. 2 is a schematic diagram showing a configuration example of the light irradiation device; Fig. 3 is a schematic diagram of a modified example of the light irradiation device; Fig. 4 is a side view showing the appearance of a light emitting element mounting portion of the light irradiation device; Fig. 5 is a schematic diagram showing a configuration example of optical components; Fig. 6 is a schematic diagram of another modified example of the light irradiation device; Fig. 7 is a schematic diagram of the light irradiation device of the second embodiment; Fig. 8 is a schematic diagram of the light irradiation device of the third embodiment.

[0009] Hereinafter, embodiments for carrying out the present disclosure will be described with reference to the drawings. The following description is intended to embody the technical concept of the present disclosure, and unless otherwise specified, the present disclosure is not limited to the following description. In each drawing, components having the same function may be assigned the same reference numerals. For convenience, the embodiments may be shown separately in consideration of ease of explanation or understanding of the main points, but partial substitution or combination of configurations shown in different embodiments or examples is possible. In the embodiments shown later, differences from the previously shown embodiments will be mainly described, and redundant description of matters common to the previously shown embodiments may be omitted. The size and positional relationship of components shown in each drawing may be exaggerated for clarity.

[0010] First Embodiment FIG. 1 is a diagram showing an example of an in vivo light irradiation assembly 100 using a light irradiation device 10 according to a first embodiment. The in vivo light irradiation assembly 100 includes a catheter 50 and a light irradiation device 10 inserted into the catheter 50. The catheter 50 is filled with a refrigerant 51 at least during use. The in vivo light irradiation assembly 100 is used for treatment, diagnosis, sensing, and the like. The light irradiation device 10 is introduced into a living body by, for example, inserting it into the catheter 50 in the "insertion direction" indicated by the white arrow in the figure. Because the light irradiation device 10 is a heat-generating body, a refrigerant 51 is supplied into the catheter 50, and the heat-generating portion is cooled during use. The refrigerant 51 may be, for example, saline, blood, lymph, or the like, and the refrigerant temperature is, for example, approximately 10°C to 36°C. The light irradiation device 10 is inserted into the vicinity of a target site such as an affected area in a living body using a catheter 50, so that it is possible to directly irradiate light onto an affected area such as a tumor, and to inspect and confirm a target site for diagnosis, sensing, etc., without using an optical fiber.

[0011] FIG. 2A is a schematic diagram of a light irradiation device 10A, which is one example of the configuration of the light irradiation device 10. The light irradiation device 10A includes a light emitting element 11 that emits light of a specific wavelength, a support 12 on which the light emitting element 11 is mounted, a first insulating layer 16 that covers at least a portion of the light emitting element 11, insulated wires 14a and 14b that are electrically connected to the light emitting element 11, and a case 15. In the first embodiment, the case 15 includes a first case portion 15-1 and a second case portion 15-2. However, as described below, the case portion does not necessarily have to be separated into two, and the second case portion may be omitted. The light emitting element 11 has a first surface 111 that emits light of a specific wavelength and a second surface 112 opposite the first surface 111. The first insulating layer 16 is, for example, an insulating resin layer, and covers a portion of the light emitting element 11 excluding the first surface 111. The insulated wires 14a and 14b are electrically connected to the light-emitting element 11 in an area excluding the first surface 111. The first case portion 15-1 seals the first surface 111 of the light-emitting element 11 in a first space 153, and the second case portion 15-2 seals the second surface 112 of the light-emitting element 11 in a second space 154. At least the portion of the case 15 that extracts light emitted from the first surface 111 of the light-emitting element 11 to the outside is optically transparent.

[0012] The light emitting element 11 is held on the support 12 so that the first surface 111, which is the light emitting surface, and the second surface 112, which is the reflecting surface, do not interfere with other components. In the coordinate system of FIG. 2A, the optical axis direction of the light emitting element 11 is the Z direction, the mounting direction of the light emitting element 11 on the support 12 is the Y direction, and the direction perpendicular to the Z direction and the Y direction is the X direction. The longitudinal direction of the support 12 is parallel to the Z direction. The light irradiation device 10A is inserted into the catheter 50 in the +Z direction. The insulated electric wires 14a and 14b extend in the -Z direction. The support 12 is made of silicon (Si), aluminum nitride (AlN), silicon nitride (SiN), sapphire (Al ２ O ３ The light emitting element 11 is disposed on a light emitting element mounting surface 121 of the support 12.

[0013] The first insulating layer 16 integrally covers at least a portion of the light-emitting element 11 excluding the first surface 111 and the second surface 112, the electrical connection portions between the light-emitting element 11 and the insulated wires 14 a and 14 b, and a portion of the support body 12. The first insulating layer 16 is preferably made of a resin that has high thermal conductivity and is electrically insulating. The first insulating layer 16 seals the laminated portions of the support body 12, the light-emitting element 11, and the insulated wires 14 a and 14 b to prevent the refrigerant 51 from entering the first space 153 and the second space 154, and also comes into contact with the refrigerant 51 at its outer surface to release heat from the light-emitting element 11.

[0014] In the first embodiment, the case 15 has a first case part 15-1 that seals the first surface 111 of the light-emitting element 11 in a first space 153, and a second case part 15-2 that seals the second surface 112 of the light-emitting element 11 in a second space 154. The leading end of the first case part 15-1 on the +Z side is sealed with a second insulating layer 17, and the rear end of the second case part 15-2 on the −Z side is sealed with a third insulating layer 18.

[0015] The second insulating layer 17 and the third insulating layer 18 may be formed of a different type of resin than the first insulating layer 16. For example, the second insulating layer 17 and the third insulating layer 18 are formed of a resin material with a higher viscosity than the first insulating layer 16. The first insulating layer 16 is applied to cover a relatively wide area between the first case portion 15-1 and the second case portion 15-2, making resin sealing relatively easy. In contrast, the second insulating layer 17 and the third insulating layer 18 resin-seal only the small areas of the opening at the front end of the first case portion 15-1 and the opening at the rear end of the second case portion 15-2. By making the viscosity of the second insulating layer 17 and the third insulating layer 18 higher than that of the first insulating layer 16, the opening at the front end of the first case portion 15-1 and the opening at the rear end of the second case portion 15-2 are reliably sealed, preventing the intrusion of refrigerant into the first space 153 and the second space 154.

[0016] The rear end portion on the -Z side of the first case portion 15-1 is sealed with a first insulating layer 16, and a first surface 111 of the light-emitting element 11 is exposed in a first space 153 between the first insulating layer 16 and the second insulating layer 17. The front end portion on the +Z side of the second case portion 15-2 is sealed with the first insulating layer 16, and a second surface 112 of the light-emitting element 11 is exposed in a second space 154 between the first insulating layer 16 and the third insulating layer 18. The first insulating layer 16, the second insulating layer 17, and the third insulating layer 18 are all insulating resin sealing materials, even though they have different wettability and viscosity, and the wettability and viscosity may be adjusted by adding a surface conditioner to epoxy resin, silicone resin, acrylic resin, thermoplastic resin, or the like.

[0017] More preferably, the first insulating layer 16, the second insulating layer 17, and the third insulating layer 18 are made of insulating resins that are biocompatible and have high thermal conductivity. Examples of resin materials that can be used include polycarbonate (PC), polyethylene terephthalate (PET), polyimide (PI), polyurethane, and polyesterimide, whose components and compositions have been adjusted to mitigate adverse effects on living organisms. Alternatively, a coating formed by applying a polysilazane solution and silicifying it (hereinafter referred to as a polysilazane coating) can be used. When a polysilazane coating is used for the first insulating layer 16, additional resins may be provided to seal the rear end of the first case portion 15-1 and the front end of the second case portion 15-2. These additional resins may be the same resin as the resin used for the second insulating layer 17 and the third insulating layer 18, or may be different resins. Furthermore, the entire light irradiation device 10A may be coated with a polysilazane coating.

[0018] Inside the first case portion 15-1, an optical component 13 is disposed on the support 12, facing the first surface 111 of the light-emitting element 11. The optical component 13 guides light emitted from the light-emitting element 11 to the outside of the first case portion 15-1. The optical component 13 is a thin, flat-finished mirror or prism. A metapolarizing element having a thin metasurface element inserted therein may also be used as the optical component 13. The optical component 13 may also be an optical element having a lens function that controls the spread angle of light emitted from the light-emitting element 11. As will be described later with reference to FIG. 4, the optical component 13 may have two or more optical elements. For example, the optical component 13 may have an optical element having a lens function that controls the spread angle of light emitted from the light-emitting element 11, and an optical element that reflects the light whose spread angle has been controlled by the optical element at a predetermined angle.

[0019] At least the portion of the first case portion 15-1 that extracts light from the optical component 13 is formed of a light-transmitting material. In FIG. 2A , light emitted in the +Z direction from the first surface 111 of the light-emitting element 11 is emitted in the +Y direction by the optical component 13, but this example is not limiting. As long as light can be emitted outside the first case portion 15-1 without being obstructed by the second insulating layer 17 or the light-emitting element mounting surface 121 of the support body 12, light may be emitted in any direction between the −X direction and the +X direction within the XY plane. Furthermore, as long as light is not obstructed by the second insulating layer 17 or the light-emitting element 11, light may be emitted at an angle inclined toward the +Z direction or the −Z direction from the normal to the light-emitting element mounting surface 121 of the support body 12.

[0020] The first case portion 15-1 and the second case portion 15-2 may be transparent cylindrical bodies made of glass, quartz, biocompatible plastic, or the like. The outer diameter of the first case portion 15-1 and the second case portion 15-2 is, for example, 0.4 mm to 2.0 mm, and the inner diameter is 0.3 mm to 1.5 mm. As an example, a biocompatible plastic tube with an outer diameter of 0.5 mm and an inner diameter of 0.38 mm is used. The lengths of the first case portion 15-1 and the second case portion 15-2 in the Z direction may be the same or different. In FIG. 2A , because the optical component 13 is disposed in the first space 153, the length of the first case portion 15-1 in the Z direction is longer than the length of the second case portion 15-2 in the Z direction.

[0021] The support 12 on which the light-emitting element 11 is mounted protrudes from at least one of the first case portion 15-1 and the second case portion 15-2. In the configuration of FIG. 2A , the support 12 protrudes from the rear end of the second case portion 15-2. The support 12 is located between the insulated electric wires 14a and 14b in the Y direction, and together with the insulated electric wires 14a and 14b, protrudes from the third insulating layer 18 in the −Z direction at the rear end of the second case portion 15-2. The insulated electric wires 14a and 14b and the support 12 come into contact with the refrigerant and function as a heat dissipation material that dissipates heat from the light-emitting element 11 to the outside.

[0022] The width of support 12 in the X direction is smaller than the inner diameter of first case portion 15-1 and second case portion 15-2, but may be set as wide as possible within the range that can be accommodated within first case portion 15-1 and second case portion 15-2, from the viewpoint of increasing the contact area with refrigerant 51. The thickness of support 12 in the Y direction is a thickness that can stably support light-emitting element 11, and is, for example, 0.1 mm.

[0023] The insulated wires 14a and 14b extending in the −Z direction from the rear end of the second case portion 15-2 are, for example, enameled wires, in which metal wiring made of a good conductor such as Cu or Ni is coated with an insulating polyurethane coating. Instead of polyurethane, insulating resins such as polyester, polyesterimide, polyamideimide, and polyimide may be used. The insulating coating on the surface of the insulated wires 14a and 14b is used as a heat dissipation material to dissipate heat from the light-emitting element 11. When rectangular enameled wires are used as the insulated wires 14a and 14b, the resulting wiring is wider, allowing for a larger bonding area with the support 12. Furthermore, for the same cross-sectional area, rectangular enameled wires can be thinner than round enameled wires, allowing for greater miniaturization.

[0024] In this way, the light irradiation device 10A has a configuration with heat dissipation properties and electrical insulation properties. The first surface 111 and the second surface 112 of the light emitting element 11 are held in the sealed first space 153 and second space 154 of the first case portion 15-1 and the second case portion 15-2 so as not to interfere with other components, and at least a portion excluding the first surface 111 and the second surface is sealed with the first insulating layer 16. This allows the overall diameter of the light irradiation device 10A to be reduced, making it easier to insert into the catheter 50.

[0025] <Modification of Light Illumination Device> Figure 2B is a schematic diagram of a light illumination device 10B, which is a modification of the light illumination device 10A. In the light illumination device 10B, the support 12 protrudes in the +Z direction from the front end of the first case portion 15-1 and protrudes in the -XZ direction from the rear end of the second case portion 15-2. The opening on the front end side of the first case portion 15-1 is sealed with a second insulating layer 17, with the support 12 protruding. The opening on the rear end side of the second case portion 15-2 is sealed with a third insulating layer 18, with the support 12 protruding.

[0026] Similar to the light irradiation device 10A, the rear end of the first case portion 15-1 is sealed with a first insulating layer 16, and a first surface 111 of the light emitting element 11 is exposed in a first space 153 between the first insulating layer 16 and the second insulating layer 17. The front end of the second case portion 15-2 is sealed with the first insulating layer 16, and a second surface 112 of the light emitting element 11 is exposed in a second space 154 between the first insulating layer 16 and the third insulating layer 18. Between the first case portion 15-1 and the second case portion 15-2, at least a portion of the light emitting element 11 excluding the first surface 111 and the second surface 112 is integrally sealed by the first insulating layer 16 together with the support body 12 and the insulated wires 14a and 14b. The first insulating layer 16 isolates the electrical connection between the light emitting element 11 and the insulated wires 14a and 14b from the coolant 51, and also functions as a heat dissipation material that releases heat from the light emitting element 11 to the outside.

[0027] In the light irradiating device 10B, the support 12 protrudes from both the first case portion 15-1 and the second case portion 15-2, thereby further enhancing heat dissipation compared to the light irradiating device 10A. Furthermore, the space between the first case portion 15-1 and the second case portion 15-2 is sealed with a first insulating layer 16, thereby reducing the overall diameter of the light irradiating device 10B. The light irradiating device 10B is thus realized, which has heat dissipation and electrical insulation properties and can be mounted on a catheter.

[0028] Fig. 3 is a side view showing the appearance of the light emitting element mounting portion of the light irradiation device 10A of Fig. 2A or the light irradiation device 10B of Fig. 2B. The configuration of Fig. 3 shows a state before sealing with the first insulating layer 16, the second insulating layer 17, and the third insulating layer 18, with the first surface 111 and the second surface 112 of the light emitting element 11 exposed in the first space 153 and the second space 154 of the first case part 15-1 and the second case part 15-2.

[0029] The light-emitting element 11 is, for example, an edge-emitting laser element that resonates in a direction parallel to the Z axis. The light-emitting element 11 is disposed on the support 12 so that a first surface 111, which is a light-emitting surface, faces the optical component 13. A second surface 112, which is a rear end surface of the light-emitting element 11, is a reflective surface and may be coated with a highly reflective film. A laser cavity is formed between the first surface 111 and the second surface 112.

[0030] The optical component 13 guides, in a desired direction, the light emitted from the first surface 111 of the light-emitting element 11. In Fig. 3, the optical component 13 guides the output light Lout in the +Y direction, but the output light Lout may be guided in any direction as long as the light emitted from the light-emitting element 11 can be extracted to the outside from the first case portion 15-1 without being obstructed by the second insulating layer 17 or the support body 12.

[0031] The insulated wires 14a and 14b are positioned so as not to interfere with the optical output of the edge-emitting laser element. A portion of the insulating coating of the insulated wire 14a is removed, and the internal metal wiring is electrically connected directly or indirectly to one electrode of the light-emitting element 11. A portion of the insulating coating of the insulated wire 14b is removed, and the internal metal wiring is electrically connected to the other electrode of the light-emitting element 11. In the example of FIG. 3 , a conductive film 124 is formed from the light-emitting element mounting surface 121 of the support 12, through the side surface, to the back surface 122, and the internal metal wiring of the insulated wire 14b is connected to the conductive film 124. This provides electrical connection between the other electrode of the light-emitting element 11 and the insulated wire 14b. By providing the conductive film 124 for electrical connection on the surface of the support 12, the conductive film 124 can be used as a heat dissipation member together with the first insulating layer 16. Furthermore, as will be described later with reference to FIG. 5 , a second support may be disposed between the insulated wire 14a and the light-emitting element 11. By sandwiching the light emitting element 11 between the support 12 and the second support, heat dissipation can be improved.

[0032] The semiconductor material and composition of the light-emitting element 11 are designed to emit laser light of a desired wavelength. When the light-emitting element 11 is used as an ultraviolet laser, a violet laser, a blue laser, or a green laser, GaN-based materials such as GaN, InGaN, and AlGaN are used. When the light-emitting element 11 is used as a red laser, an infrared laser, or a near-infrared laser, GaAs-based materials such as GaAs and AlGaAs, or InP-based materials such as InAlGaP and GaInP are used. To make the light-emitting device 10A or 10B suitable for mounting in the catheter 50, the cavity length of the laser element may be made as short as possible, while the width direction may be widened to the maximum width that can be accommodated in the first case portion 15-1 and the second case portion 15-2 to form a wide ridge to ensure the gain of the active layer. The ridge width may be designed to be, for example, 2 μm to 100 μm. The transverse mode may be multimode or single mode.

[0033] Unlike fiber-based irradiation devices, the light emitted by the light-emitting element 11 is linearly polarized, and the direction of the linear polarization after emission can be changed by changing the reflection direction using an optical component 13 such as a mirror. This makes it possible, for example, to reduce the reflectance when the light is incident on a living body and improve the transmittance through the living body. Even light that is in a specific polarization state when emitted as laser light may change its polarization state or become depolarized while passing through a transmission medium such as an optical fiber. In this embodiment, light can be directly irradiated onto an affected area inside the body without using an optical fiber, so light can be irradiated onto a target location such as an affected area while maintaining a specific polarization state.

[0034] FIG. 4 is a schematic diagram showing an example configuration of the optical component 13. FIG. 4 shows the state before the first surface 111 and the second surface 112 of the light-emitting element 11 are housed in the first case portion 15-1 and the second case portion 15-2. The optical component 13 may have two or more optical elements. For example, the optical component 13 may have an optical element 131 having a lens function that controls the spread angle of light emitted from the light-emitting element 11, and an optical element 132 that reflects the light whose spread angle has been controlled by the optical element 131 at a predetermined angle. In this example configuration, the incident surface of the optical element 131 is formed as a convex surface, but the reflective surface of the optical element 132 may also be formed as a concave surface. In the example of FIG. 4, the optical element 132 reflects the light collimated by the optical element 131 in the +Y direction, but the reflection direction or reflection angle of the optical element 132 can be designed as appropriate. By integrating the multiple reflective optical elements 131 and 132, the overall size of the optical component 13 can be reduced, thereby miniaturizing the light irradiation device 10.

[0035] 5 is a schematic diagram of a light irradiation device 10C, which is yet another modified example of the light irradiation device of the first embodiment. In the light irradiation device 10C, the light emitting element 11 is sandwiched between a first support 12-1 and a second support 12-2. The first support 12-1 contacts the top surface of the light emitting element 11, and the second support 12-2 contacts the bottom surface of the light emitting element 11. By sandwiching the light emitting element 11 between the first support 12-1 and the second support 12-2, heat can be efficiently dissipated to the upper and lower sides of the light emitting element 11, thereby improving the heat dissipation performance of the light irradiation device 10. The rear end of at least one of the first support 12-1 and the second support 12-2 may be extended in the −Z direction and protrude rearward from the second case portion 15-2. In FIG. 5, the direction or angle of the reflecting surface of the optical component 13 may be determined so that the light emitted from the light-emitting element 11 is extracted in a direction that is not obstructed by the first support 12-1 or the second support 12-2, for example, in the +X direction or the −X direction.

[0036] The light irradiation device 10A, 10B, or 10C of the first embodiment may be used in combination with an endoscope. The light emitting element 11 can be used not only as a laser light source for treatment but also as an illumination light source. In either case, it exhibits heat dissipation properties and electrical insulation, and is effective as a light irradiation device that can be mounted on a catheter. Unlike optical fibers, insulated wires with an insulating coating are highly flexible. Furthermore, a configuration in which the light emitting element itself is mounted on the support 12 has excellent integration properties and a wide range of applications for sensors.

[0037] Second Embodiment FIG. 6 is a schematic diagram of a light irradiation device 20 according to a second embodiment. In the second embodiment, a case 25 is used in which a first case portion and a second case portion are connected by a connector. As in the first embodiment, the light irradiation device 20 is inserted into a catheter 50 (see FIG. 1 ) and can be used while being cooled by a refrigerant 51. The light irradiation device 20 includes a light-emitting element 11 that emits light of a specific wavelength, a support 12 on which the light-emitting element 11 is mounted, an insulating first insulating layer 26 that covers at least a portion of the light-emitting element 11, insulated wires 14a and 14b that are electrically connected to the light-emitting element 11, and a case 25. The light-emitting element 11 has a first surface 111 that emits light of a specific wavelength and a second surface 112 opposite the first surface 111. The first insulating layer 26 covers at least a portion of the light-emitting element 11, excluding the first surface 111 and the second surface 112. The insulated wires 14 a and 14 b are electrically connected to the light emitting element 11 in the area excluding the first surface 111 .

[0038] The case 25 has a first case portion 251 that seals the first surface 111 of the light-emitting element 11 in a first space 253, a second case portion 252 that seals the second surface 112 of the light-emitting element 11 in a second space 254, and a connecting portion 255 that connects the first case portion 251 and the second case portion 252. The first case portion 251 and the second case portion 252 are cylindrical, and the connecting portion 255 has a shape in which a side of the cylindrical shape is cut out. At least a portion of the light-emitting element 11, electrical connecting portions between the light-emitting element 11 and the insulated wires 14a and 14b, and a portion of the support body 12 are integrally covered by a first insulating layer 26 and supported by the connecting portion 255. At least a portion of the first case portion 251 that extracts light emitted from the first surface 111 of the light-emitting element 11 to the outside is light-transmitting.

[0039] The portion of the light-emitting element 11 that is integrally covered by the first insulating layer 26 with the support 12 and the insulated wires 14a and 14b between the first surface 111 and the second surface 112 is stably supported by the connecting portion 255 of the case 25. The connecting portion 255 does not need to support the entire periphery of the portion covered by the first insulating layer 26, but only needs to support the minimum necessary area of ​​the surface of the first insulating layer 26 along the longitudinal direction (Z direction) of the support 12. The first insulating layer 26 seals the laminated portion of the support 12, the light-emitting element 11, and the insulated wires 14a and 14b to prevent the refrigerant 51 from entering the first space 253 and the second space 254, and also comes into contact with the refrigerant 51 at its outer surface to release heat from the light-emitting element 11.

[0040] The first case portion 251, the second case portion 252, and the connecting portion 255 may be integrally molded from a biocompatible plastic or the like. The leading end of the first case portion 251 on the +Z side is sealed with a second insulating layer 27, and the rear end of the second case portion 252 on the -Z side is sealed with a third insulating layer 28. The second insulating layer 27 and the third insulating layer 28 may be formed from a different type of resin than the first insulating layer 26. For example, the second insulating layer 27 and the third insulating layer 28 may be formed from a material that has a higher wettability with respect to the case 25 than the first insulating layer 26, or a material that has a lower viscosity than the first insulating layer 26. This allows the small openings in the first case portion 251 and the second case portion 252 to be reliably sealed.

[0041] From the rear end of the first case portion 251 to the front end of the second case portion 252, at least a portion of the light-emitting element 11, excluding the first surface 111 and the second surface 112, is integrally sealed with the support 12 and the insulated wires 14a and 14b by a first insulating layer 26. The first surface 111 of the light-emitting element 11 is exposed in a first space 253 formed in the first case portion 251 between the first insulating layer 26 and the second insulating layer 27. The second surface 112 of the light-emitting element 11 is exposed in a second space 254 formed in the second case portion 252 between the first insulating layer 26 and the third insulating layer 28. The first insulating layer 26, the second insulating layer 27, and the third insulating layer 28 are preferably made of insulating resin that is biocompatible and has high thermal conductivity.

[0042] Inside the first case portion 251, an optical component 13 is disposed on the support 12, facing the first surface 111 of the light-emitting element 11. The optical component 13 guides light emitted from the light-emitting element 11 to the outside of the first case portion 251. The optical component 13 is a thin, flat-finished mirror or prism. A metapolarizing element having a thin metasurface element inserted therein may also be used as the optical component 13. The optical component 13 may also be an optical element having a lens function that controls the spread angle of light emitted from the light-emitting element 11. As described with reference to FIG. 4 , the optical component 13 may have two or more optical elements. For example, the optical component 13 may have an optical element 131 having a lens function that controls the spread angle of light emitted from the light-emitting element 11, and an optical element 132 that reflects the light whose spread angle has been controlled by the optical element 131 at a predetermined angle. By integrally configuring the optical component 13 with multiple optical elements, the overall size of the optical component 13 can be reduced, thereby enabling the light irradiation device 20 to be miniaturized.

[0043] 6, light emitted in the +Z direction from the first surface 111 of the light-emitting element 11 is emitted in the +Y direction by the optical component 13, but this example is not limiting. As long as light can be emitted to the outside of the first case portion 251 without interfering with the light-emitting element mounting surface 121 of the support body 12 or the second insulating layer 27, light may be emitted in any direction between the −X direction and the +X direction within the XY plane. Furthermore, as long as the function of the second insulating layer 27 or the light-emitting element 11 is not impaired, light may be emitted at an angle inclined in the +Z direction or the −Z direction from the normal to the light-emitting element mounting surface 121 of the support body 12.

[0044] The support 12 on which the light-emitting element 11 is mounted protrudes outside at least one of the first case portion 251 and the second case portion 252. In the configuration example shown in FIG. 6 , the support 12 protrudes from the case 25 on both the tip side of the first case portion 251 and the rear side of the second case portion 252. The opening on the tip side of the first case portion 251 is sealed with a second insulating layer 27 while the support 12 protrudes. The opening on the rear side of the second case portion 252 is sealed with a third insulating layer 28 while the support 12 protrudes. As shown in FIG. 5 , the light-emitting element 11 may be sandwiched between a first support 12-1 and a second support 12-2 to improve heat dissipation. The first support 12-1 and the second support 12-2 may protrude in the +Z or −Z direction from at least one of the first case portion 251 and the second case portion 252. When the first support 12-1 and the second support 12-2 protrude from the first case portion 251 to the +Z side, the direction or angle of the reflecting surface of the optical component 13 may be adjusted to extract the emitted light in the +X direction or the -X direction.

[0045] Between the first case portion 251 and the second case portion 252, at least a portion of the light emitting element 11 excluding the first surface 111 and the second surface 112 is integrally sealed together with the support body 12 and the insulated wires 14a and 14b by the first insulating layer 26 and is supported by the connecting portion 255. The first insulating layer 26 isolates the electrical connection portions between the light emitting element 11 and the insulated wires 14a and 14b from the refrigerant 51 and also functions as a heat dissipation material that dissipates heat from the light emitting element 11 to the outside. When two-core enameled wires are used as the insulated wires 14a and 14b, wide wiring is obtained, enabling heat dissipation on both sides.

[0046] The light irradiation device 20 of the second embodiment may be used in combination with an endoscope. The light emitting element 11 can be used not only as a laser light source for treatment but also as an illumination light source. In either case, it exhibits heat dissipation properties and electrical insulation, and is effective as a light irradiation device that can be mounted on a catheter. Unlike optical fibers, insulated electric wires with an insulating coating are highly flexible. Furthermore, a configuration in which the light emitting element itself is mounted on the support 12 has excellent integration properties and a wide range of applications for sensors.

[0047] Third Embodiment Fig. 7 is a schematic diagram of a light irradiation device 30 according to a third embodiment. In the third embodiment, only the region including the first surface 111 of the light-emitting element 11 is housed within a case 15, and the portion extending from the case 15 in the -Z direction is sealed with an insulating resin. As in the first and second embodiments, the light irradiation device 30 is inserted into a catheter 50 (see Fig. 1) and can be used while being cooled by a refrigerant 51. The light irradiation device 30 includes a light-emitting element 11 having a first surface 111 that emits light of a predetermined wavelength, a support 12 on which the light-emitting element 11 is mounted, a first insulating layer 16 that covers at least a portion of the light-emitting element 11 except for the first surface 111, insulated wires 14a and 14b that are electrically connected to the light-emitting element 11 in the region excluding the first surface 111, and a case 15 that seals the first surface 111 within a first space 153.

[0048] The first insulating layer 16 seals the rear end (-Z side) of the case 15 and extends from the rear end of the case 15, integrally covering at least a portion of the light-emitting element 11 except for the first surface 111, the electrical connection between the light-emitting element 11 and the insulated wires 14a and 14b, and a portion of the support 12. In the example shown in FIG. 7 , the first insulating layer 16 covers the second surface 112 on the rear side of the light-emitting element 11, along with the support 12 and the insulated wires 14a and 14b. The first insulating layer 16 is preferably made of an electrically insulating resin with high thermal conductivity. The first insulating layer 16 continuously seals the opening on the rear end side (-Z side) of the case 15 and the stacked portions of the support 12, the light-emitting element 11, and the insulated wires 14a and 14b to prevent the refrigerant 51 from entering the first space 153, and also comes into contact with the refrigerant 51 at its outer surface, thereby dissipating heat from the light-emitting element 11.

[0049] The support 12 protrudes outward from one or both of the case 15 and the first insulating layer 16. By protruding the support 12 outward from the case 15 and / or the first insulating layer 16, the support 12 can come into contact with the coolant 51 and release heat outward from the light irradiation device 30.

[0050] The light irradiation device 30 has a second insulating layer 17 that seals the front end (+Z side) of the case 15. The rear end (-Z side) of the case 15 is sealed with the first insulating layer 16 described above. The first insulating layer 16 is formed of an insulating resin material, and the second insulating layer 17 may be formed of a different type of resin material from the first insulating layer 16. For example, the second insulating layer 17 is formed of a resin material that is more wettable with respect to the case 15 than the first insulating layer 16, or a resin material that has a lower viscosity than the first insulating layer 16. The first surface 111 of the light emitting element 11 is exposed in the first space 153 between the first insulating layer 16 and the second insulating layer 17. The length of the first insulating layer in the Z direction is longer than the length of the second insulating layer in the Z direction. The first insulating layer 16 is applied to cover a relatively wide portion extending from the rear end of the case 15, making resin sealing relatively easy. In contrast, second insulating layer 17 resin-seals a tiny region, namely the opening at the tip of case 15. The viscosity of second insulating layer 17 is set lower than that of first insulating layer 16, thereby reliably sealing the opening at the tip of case 15 and preventing the refrigerant from entering first space 153.

[0051] Preferably, the first insulating layer 16 and the second insulating layer 17 are made of an insulating resin that is biocompatible and has high thermal conductivity. Examples of resin materials that can be used include polycarbonate (PC), polyethylene terephthalate (PET), polyimide (PI), polyurethane, and polyesterimide, whose components and compositions are adjusted to mitigate adverse effects on living bodies. The first insulating layer 16 and the second insulating layer 17 may also be polysilazane coated. The first insulating layer 16 and the second insulating layer 17 may be made of the same material or different materials. For example, the second insulating layer 17 may be made of a resin with a higher viscosity than the first insulating layer 16. When the first insulating layer 16 is made of polysilazane, it is desirable to use an additional resin with a higher viscosity than polysilazane to prevent refrigerant from entering from the rear end of the case 15. This additional resin may be the same resin as the resin used for the second insulating layer 17 or a different resin.

[0052] As in the first and second embodiments, an optical component 13 facing the first surface 111 of the light-emitting element 11 is disposed on the support 12 inside the case 15. The optical component 13 guides the light emitted from the light-emitting element 11 to the outside of the case 15. The optical component 13 is a flattened mirror or prism. A metapolarizing element with a metasurface element inserted may be used as the optical component 13, or, as described with reference to FIG. 4 , the optical component 13 may be integrally formed from a plurality of optical elements.

[0053] 5, the light emitting element 11 may be sandwiched between a first support 12-1 and a second support 12-2 to improve heat dissipation. In this case, the first support 12-1 and the second support 12-2 may protrude in the +Z or −Z direction from at least one of the first case portion 251 and the second case portion 252. When the first support 12-1 and the second support 12-2 protrude from the case 15 to the +Z side, the direction or angle of the reflecting surface of the optical component 13 may be adjusted to extract the emitted light in the +X or −X direction.

[0054] The configuration of the third embodiment allows the light irradiation device 30 to be further miniaturized, facilitating insertion into the catheter 50. In addition, the entire area of ​​the light emitting element 11 except for the first surface 111 is sealed with the first insulating layer 16, and the support 12 and the insulated wires 14a and 14b are pulled out of the first insulating layer 16, thereby improving heat dissipation.

[0055] The present invention can be used not only as a light irradiation device inserted into a medical catheter but also in other medical applications, such as sensors that require localized light irradiation in combination with a refrigerant.

[0056] Embodiments of the present disclosure may include, for example, the following configurations: (Item 1) A light-emitting device comprising: a light-emitting element having a first surface that emits light of a predetermined wavelength; a support on which the light-emitting element is mounted; a first insulating layer that covers at least a portion of the light-emitting element excluding the first surface; an insulated wire electrically connected to the light-emitting element in an area excluding the first surface; and a case that seals the first surface within a first space. (Item 2) The light-emitting device according to Item 1, wherein the first insulating layer seals a rear end of the case and continues from the rear end of the case, integrally covering at least a portion of the light-emitting element excluding the first surface, an electrical connection portion between the light-emitting element and the insulated wire, and a portion of the support. (Item 3) The light-emitting device according to Item 1 or 2, wherein the support protrudes from one or both of the case and the first insulating layer. (Item 4) The light irradiating device according to any one of Items 1 to 3, further comprising: a first insulating layer sealing a front end of the case; and a second insulating layer sealing a rear end of the case, wherein the first insulating layer is an insulating resin sealing a rear end of the case, and the second insulating layer is formed of a resin material different from that of the first insulating layer. (Item 5) The case includes a first case portion sealing the first surface of the light emitting element in the first space, and a second case portion sealing a second surface of the light emitting element opposite the first surface in the second space, wherein the first insulating layer integrally covers at least a portion of the light emitting element excluding the first surface and the second surface, an electrical connection portion between the light emitting element and the insulated wire, and a portion of the support, between the first case portion and the second case portion. (Item 6) The light irradiating device according to Item 5, further comprising: a second insulating layer sealing a front end of the first case portion; and a third insulating layer sealing a rear end of the second case portion. (Item 7) The light irradiation device according to Item 6, wherein a rear end of the first case portion is sealed with the first insulating layer, and the first surface of the light emitting element is exposed in the first space between the first insulating layer and the second insulating layer.(Item 8) The light irradiating device according to Item 6, wherein a tip end of the second case portion is sealed with the first insulating layer, and the second surface of the light emitting element is exposed in the second space between the first insulating layer and the third insulating layer. (Item 9) The light irradiating device according to Item 6, wherein the second insulating layer and the third insulating layer are formed of a material different from that of the first insulating layer. (Item 10) The light irradiating device according to Item 5, wherein the case has a connection portion connecting the first case portion and the second case portion, and at least a portion of the light emitting element, an electrical connection portion between the light emitting element and the insulated wire, and a portion of the support are integrally covered by the first insulating layer and supported by the connection portion. (Item 11) The light irradiating device according to Item 5, wherein the support protrudes outside at least one of the first case portion and the second case portion. (Item 12) The light irradiation device according to any one of Items 1 to 11, further comprising: an optical component that is disposed inside the first space and that guides the light emitted from the first surface of the light-emitting element to the outside of the case. (Item 13) An in-vivo light irradiation assembly, comprising: a catheter; and the light irradiation device according to any one of Items 1 to 12 that is inserted into the catheter, wherein the inside of the catheter is filled with a refrigerant at least during use.

[0057] This application claims priority based on Japanese Patent Application No. 2023-211660 filed with the Japan Patent Office on December 15, 2023, and includes the entire contents of this Japanese patent application.

[0058] 10, 10A, 10B, 20 Light irradiation device 11 Light emitting element 111 First surface 112 Second surface 12, 12-1, 12-2 Support 121 Light emitting element mounting surface 122 Back surface 124 Conductive film 13 Optical component 14a, 14b Insulated wire 15, 25 Case 15-1, 251 First case part 15-2, 252 Second case part 16, 26 First insulating layer 17, 27 Second insulating layer 18, 28 Third insulating layer 50 Catheter 51 Refrigerant 153, 253 First space 154, 254 Second space 255 Connection part

Claims

1. A light irradiation device comprising: a light emitting element having a first surface that emits light of a predetermined wavelength; a support on which the light emitting element is mounted; a first insulating layer that covers at least a portion of the light emitting element except for the first surface; an insulated wire that is electrically connected to the light emitting element in an area other than the first surface; and a case that seals the first surface within a first space.

2. The light irradiation device according to claim 1, wherein the first insulating layer seals the rear end of the case and continues from the rear end of the case to integrally cover at least a portion of the light-emitting element excluding the first surface, an electrical connection portion between the light-emitting element and the insulated wire, and a portion of the support body.

3. The light irradiation device according to claim 1, wherein the support protrudes from one or both of the case and the first insulating layer.

4. A light irradiation device as claimed in any one of claims 1 to 3, further comprising: a second insulating layer sealing a front end portion of the case, the first insulating layer being an insulating resin sealing a rear end portion of the case, and the second insulating layer being formed of a resin material different from that of the first insulating layer.

5. The light irradiation device according to claim 1, wherein the case has a first case part that seals the first surface of the light-emitting element in the first space, and a second case part that seals a second surface of the light-emitting element opposite the first surface in the second space, and the first insulating layer integrally covers, between the first case part and the second case part, at least a portion of the light-emitting element excluding the first surface and the second surface, an electrical connection part between the light-emitting element and the insulated wire, and a portion of the support.

6. The light irradiation device according to claim 5, further comprising: a second insulating layer sealing a front end portion of the first case portion; and a third insulating layer sealing a rear end portion of the second case portion.

7. The light irradiation device according to claim 6, wherein a rear end of the first case portion is sealed with the first insulating layer, and the first surface of the light emitting element is exposed in the first space between the first insulating layer and the second insulating layer.

8. The light irradiation device according to claim 6, wherein a tip portion of the second case portion is sealed with the first insulating layer, and the second surface of the light emitting element is exposed in the second space between the first insulating layer and the third insulating layer.

9. The light irradiation device according to claim 6, wherein the second insulating layer and the third insulating layer are formed of a material different from that of the first insulating layer.

10. The light irradiation device according to claim 5, wherein the case has a connection portion that connects the first case portion and the second case portion, and at least a portion of the light-emitting element, an electrical connection portion between the light-emitting element and the insulated wire, and a portion of the support are integrally covered by the first insulating layer and supported by the connection portion.

11. The light irradiation device according to claim 5, wherein the support body protrudes outside at least one of the first case portion and the second case portion.

12. The light irradiation device according to any one of claims 1 to 11, further comprising: an optical component that is disposed inside the first space and guides the light emitted from the first surface of the light-emitting element to the outside of the case.

13. An in vivo light irradiation assembly comprising: a catheter; and a light irradiation device according to any one of claims 1 to 12, which is inserted into the catheter, and the inside of the catheter is filled with a refrigerant at least during use.

Images