Patent Publication Number: US-2021186612-A1

Title: Optical probe

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is a continuation of International Application No. PCT/JP2019/033979, filed on Aug. 29, 2019 which claims the benefit of priority of the prior Japanese Patent Application No. 2018-168432, filed on Sep. 10, 2018, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     The present disclosure relates to an optical probe. 
     A technology for performing treatment inside a body of a patient has been known. This kind of technology is used in, for example, a laser cautery device. The laser cautery device is a device that, for example, inserts a catheter in which an optical fiber is inserted into the body of the patient, outputs a laser beam for cautery from a distal end of the optical fiber to irradiate a target portion, such as an affected area, and performs treatment (see Japanese Unexamined Patent Application Publication No. 2017-535810). A distal end side of the optical fiber inserted in the catheter may be referred to as an optical probe. In general, in the optical probe, a holder member for holding the optical fiber is mounted on the distal end side of the optical fiber. 
     For example, there may be a case in which it is desired to insert a catheter into a blood vessel of a patient and irradiate a site on a wall surface of the blood vessel with a beam, such as a laser beam. However, in this case, the optical fiber of the optical probe is located approximately parallel to the blood vessel; therefore, in some cases, even if a beam is output from the distal end of the optical fiber parallel to an optical axis of the optical fiber, the beam travels forward in the blood vessel and it becomes difficult to irradiate a target site, such as an affected area, with the beam. Therefore, it is preferable to change a traveling direction of the beam output from the optical fiber to a sideward direction and causes the beam to be oriented toward the wall surface of the blood vessel. 
     SUMMARY 
     There is a need for providing an optical probe capable of changing a traveling direction of an output beam to a sideward direction. 
     According to an embodiment, an optical probe includes: a holder member that is mounted on a distal end side of an optical fiber and holds the optical fiber; and a traveling direction changing unit that changes a traveling direction of an output beam to a sideward direction with respect to the optical fiber. Further, the traveling direction changing unit is a reflector that is joined to a part of a surface of the holder member and reflects the output beam. 
     According to an embodiment, an optical probe includes: a holder member that is mounted on a distal end side of an optical fiber and holds the optical fiber; and a traveling direction changing unit that changes a traveling direction of an output beam to a sideward direction with respect to the optical fiber. Further, the traveling direction changing unit is a part of the holder member and is configured with a reflecting portion that reflects the output beam. 
     According to an embodiment, an optical probe includes: a traveling direction changing unit that changes a traveling direction of a beam output from an optical fiber to a sideward direction with respect to the optical fiber. Further, the traveling direction changing unit is arranged on an end face of the optical fiber. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic diagram illustrating an overall configuration of an optical probe according to a first embodiment; 
         FIG. 2  is a schematic diagram illustrating an overall configuration of an optical probe according to a second embodiment; 
         FIG. 3  is a schematic diagram illustrating an overall configuration of an optical probe according to a third embodiment; 
         FIG. 4  is a schematic diagram illustrating an overall configuration of an optical probe according to a fourth embodiment; 
         FIG. 5  is a diagram for explaining one example of a method of manufacturing the optical probe illustrated in  FIG. 2 ; 
         FIG. 6  is a diagram for explaining one example of a method of manufacturing the optical probe illustrated in  FIG. 3 ; 
         FIG. 7  is a diagram for explaining another example of the method of manufacturing the optical probe illustrated in  FIG. 2 ; 
         FIG. 8  is a schematic diagram illustrating an overall configuration of an optical probe according to a fifth embodiment; 
         FIG. 9  is a schematic diagram illustrating an overall configuration of an optical probe according to a sixth embodiment; 
         FIG. 10  is a diagram for explaining one example of a method of manufacturing the optical probe according to the fifth embodiment; 
         FIG. 11A  is a diagram for explaining an example of a shape of a reflecting surface; 
         FIG. 11B  is a diagram for explaining an example of the shape of the reflecting surface; 
         FIG. 11C  is a diagram for explaining an example of the shape of the reflecting surface; 
         FIG. 12A  is a schematic diagram illustrating an overall configuration of an optical probe according to a seventh embodiment; 
         FIG. 12B  is a schematic diagram illustrating an overall configuration of the optical probe according to the seventh embodiment; 
         FIG. 13  is a schematic diagram illustrating an overall configuration of an optical probe according to an eighth embodiment; 
         FIG. 14  is a schematic diagram illustrating an overall configuration of an optical probe according to a ninth embodiment; 
         FIG. 15  is a diagram for explaining one example of a method of manufacturing the optical probe according to the seventh embodiment; 
         FIG. 16A  is a schematic diagram illustrating an overall configuration of an optical probe according to a tenth embodiment; 
         FIG. 16B  is a schematic diagram illustrating an overall configuration of the optical probe according to the tenth embodiment; 
         FIG. 17  is a schematic diagram illustrating an overall configuration of an optical probe according to an eleventh embodiment; 
         FIG. 18  is a schematic diagram illustrating an overall configuration of an optical probe according to a twelfth embodiment; 
         FIG. 19A  is a schematic diagram illustrating an overall configuration of an optical probe according to a thirteenth embodiment; 
         FIG. 19B  is a schematic diagram illustrating an overall configuration of the optical probe according to the thirteenth embodiment; 
         FIG. 20  is a diagram for explaining one example of a method of manufacturing the optical probe illustrated in  FIGS. 19A and 19B ; 
         FIG. 21  is a schematic diagram illustrating an overall configuration of a first configuration example of an optical fiber; 
         FIG. 22  is a schematic diagram illustrating an overall configuration of a second configuration example of an optical fiber; 
         FIG. 23  is a schematic diagram illustrating an overall configuration of an optical probe according to a fourteenth embodiment; and 
         FIG. 24  is a schematic diagram illustrating an overall configuration of a third configuration example of an optical fiber. 
     
    
    
     DETAILED DESCRIPTION 
     In the related art, there is a limitation in the size of the optical probe that is inserted in to a body, such as a blood vessel, and therefore, it is difficult to adopt a complicated configuration as a means for changing a traveling direction of a beam. Further, if a means having a complicated configuration is adopted, in some cases, it may be difficult to manufacture the means with a small size. Furthermore, in the technology described in Japanese Unexamined Patent Application Publication No. 2017-535810, a reflecting member is likely to rotate in a hollow hole, and it is difficult to fix a rotation direction, which is a problem. 
     Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The present disclosure is not limited by the embodiments described below. Further, in the description of the drawings, the same or corresponding components are denoted by the same reference symbols appropriately, and explanation thereof will be omitted appropriately. Furthermore, the drawings are schematic, and dimensional relations among the components, ratios among the components, and the like may be different from the actual ones. Moreover, the drawings may include portions that have different dimensional relations or ratios. 
     First Embodiment 
       FIG. 1  is a schematic diagram illustrating an overall configuration of an optical probe according to a first embodiment. An optical probe  10  is used in, for example, a laser cautery device for treatment and is inserted into a lumen of a catheter. 
     The optical probe  10  includes an optical fiber  1 , a holder member  2 , and a reflecting coating  3 . The optical fiber  1  includes a glass optical fiber  1   a  having a core portion and a cladding portion, and a covering  1   b  that is formed on an outer circumference of the glass optical fiber  1   a . In the optical fiber  1 , the covering  1   b  is removed on a distal end side, and a predetermined length of the glass optical fiber  1   a  is exposed. The optical fiber  1  transmits laser beam L in the glass optical fiber  1   a  and outputs the laser beam L from a distal end thereof. The laser beam L is, for example, a laser beam for cautery, and a wavelength thereof belongs to, for example, a 980-nanometer (nm) wavelength range. The 980-nm wavelength range is, for example, a wavelength range of 900 nm to 1000 nm. A proximal end side of the optical fiber  1  is optically connected to a laser beam source that generates the laser beam L. 
     The glass optical fiber  1   a  is, for example, a multi-mode optical fiber, and has a step-index (SI) or graded-index (GI) refractive index profile. The glass optical fiber  1   a  with a core diameter of 65 micrometers (μm) or larger is appropriate for transmission of high-power beam, but the glass optical fiber  1   a  is not specifically limited. 
     The holder member  2  is a member for holding the optical fiber  1 , and is mounted on the distal end side of the optical fiber  1 . The holder member  2  has an approximately cylindrical outer shape and is made of glass in the present embodiment, but a constituent material is not limited to glass, but may be resin, ceramic, plastic or the like. A diameter of the holder member  2  is, for example, approximately 1 to 2 millimeters (mm) or smaller. Meanwhile, the holder member  2  has an approximately cylindrical outer shape, but may have an approximately polygonal prism outer shape. 
     The holder member  2  includes an opening hole  2   a,  an optical fiber input hole  2   b,  and an insertion hole  2   c.  The optical fiber input hole  2   b  is formed so as to extend from an end face of the holder member  2  on the left side in the figure along a cylindrical central shaft of the holder member  2  or the vicinity of the cylindrical central shaft, and has a gradually reduced inner diameter. The insertion hole  2   c  communicates with the optical fiber input hole  2   b  on a distal end side (on the right side in the figure) of the optical fiber input hole  2   b,  and is formed so as to extend along the cylindrical central shaft of the holder member  2  or the vicinity of the cylindrical central shaft. An inner diameter of the insertion hole  2   c  is slightly larger than an outer diameter of the glass optical fiber  1   a . The opening hole  2   a  communicates with the insertion hole  2   c,  and is opened on a side surface in a direction in which the insertion hole  2   c  extends, that is, on a cylindrical outer periphery of the holder member  2 . 
     The optical fiber  1  is inserted into the holder member  2  from the optical fiber input hole  2   b,  and is held by being fixed with an adhesive or the like. The exposed glass optical fiber  1   a  is inserted into the insertion hole  2   c,  and a distal end thereof protrudes to the inside of the opening hole  2   a.  The glass optical fiber  1   a  is bonded to an inner surface of the insertion hole  2   c  with an adhesive or the like. Further, a part of the optical fiber  1  input in the optical fiber input hole  2   b,  that is, a distal end portion or the like of the covering  1   b , is bonded to an inner surface of the optical fiber input hole  2   b  with an adhesive or the like. 
     The holder member  2  includes an inclined surface  2   d  at a position facing a distal end surface of the optical fiber  1 , that is, a distal end surface of the glass optical fiber  1   a , inside the opening hole  2   a.  The reflecting coating  3  as a reflector is arranged on the inclined surface  2   d.  The reflecting coating  3  is configured with a metal film, a dielectric multi-layer or the like, and is arranged on the inclined surface  2   d  by well-known vapor deposition, a chemical vapor deposition (CVD) method or the like. Meanwhile, the reflecting coating  3  may be separately manufactured and arranged by being attached to the inclined surface  2   d  with an adhesive, an adhesive material or the like. The inclined surface  2   d  and a reflecting surface of the reflecting coating  3  are inclined by approximately 45 degrees with respect to an optical axis of the optical fiber  1 . 
     The reflecting coating  3  functions as a traveling direction changing means that changes a traveling direction of the laser beam L output from the optical fiber  1  to a sideward direction with respect to the optical fiber  1 . In the present embodiment, the reflecting coating  3  reflects the laser beam L that travels along the optical axis of the optical fiber  1  after being output, and changes the traveling direction of the laser beam L by approximately 90 degrees. 
     In the optical probe  10 , the reflecting coating  3  arranged on the holder member  2  changes the traveling direction of the laser beam L output from the optical fiber  1  by approximately 90 degrees to change the traveling direction to a lateral side. According to the optical probe  10 , it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting coating  3  is arranged inside the opening hole  2   a  without protruding to an outer diameter side of the holder member  2 , so that it is possible to reduce an outer diameter of the optical probe  10 . 
     Second Embodiment 
       FIG. 2  is a schematic diagram illustrating an overall configuration of an optical probe according to a second embodiment. An optical probe  10 A includes the optical fiber  1 , a holder member  2 A, and a reflecting member  3 A. 
     The holder member  2 A is a member for holding the optical fiber  1 , and is mounted on the distal end side of the optical fiber  1 . The holder member  2 A has an approximately cylindrical outer shape and is made of glass in the present embodiment, but a constituent material is not limited to glass. A diameter of the holder member  2 A is, for example, approximately 1 to 2 mm or smaller. 
     The holder member  2 A includes an opening hole  2 Aa, an optical fiber input hole  2 Ab, and an insertion hole  2 Ac. The optical fiber input hole  2 Ab and the insertion hole  2 Ac respectively have the same configurations as the optical fiber input hole  2   b  and the insertion hole  2   c  in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. The opening hole  2 Aa communicates with the insertion hole  2 Ac, and is opened on a side surface in a direction in which the insertion hole  2 Ac extends, that is, on a cylindrical outer periphery of the holder member  2 A. 
     The optical fiber  1  is held by the holder member  2 A in the same manner as in the optical probe  10  in  FIG. 1 . 
     The reflecting member  3 A is arranged at a position facing the distal end surface of the optical fiber  1  inside the opening hole  2 Aa. The reflecting member  3 A includes a member  3 Aa that is made of glass or the like and that has a certain shape, such as a triangular prism or a tetrahedron, and a reflecting coating  3 Ab that is arranged on one surface of the member  3 Aa. The one surface of the member  3 Aa and a reflecting surface of the reflecting coating  3 Ab are inclined by approximately 45 degrees with respect to the optical axis of the optical fiber  1 . The reflecting coating  3 Ab is configured with a metal film, a dielectric multi-layer or the like, and is arranged on the member  3 Aa by well-known vapor deposition, a CVD method or the like. Meanwhile, the reflecting coating  3 Ab may be separately manufactured and arranged by being attached to the member  3 Aa with an adhesive, an adhesive material or the like. Further, the member  3 Aa is fixed to the inside of the opening hole  2   a  of the holder member  2 A with an adhesive or the like. 
     The reflecting coating  3 Ab functions as the traveling direction changing means similarly to the reflecting coating  3  in the optical probe  10  in  FIG. 1 . The reflecting coating  3 Ab as a reflector is joined to a part of a surface of the holder member  2 A. In the present embodiment, the reflecting coating  3 Ab reflects the laser beam L that travels along the optical axis of the optical fiber  1  after being output, and changes the traveling direction of the laser beam L by approximately 90 degrees. 
     According to the optical probe  10 A, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting coating  3 Ab is arranged inside the opening hole  2 Aa without protruding to an outer diameter side of the holder member  2 A, so that it is possible to reduce an outer diameter of the optical probe  10 A. 
     Third Embodiment 
       FIG. 3  is a schematic diagram illustrating an overall configuration of an optical probe according to a third embodiment. An optical probe  10 B includes the optical fiber  1 , a holder member  2 B, and a reflecting member  3 B. 
     The holder member  2 B is mounted on the distal end side of the optical fiber  1 . The holder member  2 B has an approximately cylindrical outer shape and is made of glass in the present embodiment, but a constituent material is not limited to glass. A diameter of the holder member  2 B is, for example, approximately 1 to 2 mm or smaller. 
     The holder member  2 B includes an optical fiber input hole  2 Bb and an insertion hole  2 Bc. The optical fiber input hole  2 Bb has the same configuration as the optical fiber input hole  2   b  in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. The insertion hole  2 Bc communicates with the optical fiber input hole  2 Bb on a distal end side of the optical fiber input hole  2 Bb, and is formed so as to extend along a cylindrical central shaft of the holder member  2 B or the vicinity of the cylindrical central shaft. An inner diameter of the insertion hole  2 Bc is slightly larger than an outer diameter of the glass optical fiber  1   a . The insertion hole  2 Bc penetrates to an end face  2 Bd of the holder member  2 B that is located on the right side in the figure. 
     The optical fiber  1  is held by the holder member  2 B in the same manner as in the optical probe  10  in  FIG. 1 . Meanwhile, the distal end surface of the optical fiber  1  is located on the same plane of the end face  2 Bd of the holder member  2 B or on a side that is slightly closer to the optical fiber input hole  2 Bb than the end face  2 Bd. 
     The reflecting member  3 B is arranged on the end face  2 Bd of the holder member  2 B. The reflecting member  3 B includes a member  3 Ba that has a certain shape, such as a triangular prism or a tetrahedron, and a reflecting coating  3 Bb that is arranged on one surface of the member  3 Ba. The member  3 Ba is made of a material, such as glass, that transmits the laser beam L. The one surface of the member  3 Ba and a reflecting surface of the reflecting coating  3 Bb are inclined by approximately 45 degrees with respect to the optical axis of the optical fiber  1 . The reflecting coating  3 Bb is configured with a metal film, a dielectric multi-layer or the like, and is arranged on the member  3 Ba by well-known vapor deposition, a CVD method or the like. Meanwhile, the reflecting coating  3 Bb may be separately manufactured and arranged by being attached to the member  3 Ba with an adhesive, an adhesive material or the like. Further, the member  3 Ba is fixed to the end face  2 Bd of the holder member  2 B with an adhesive or the like. Furthermore, it is preferable to form an antireflection coating on a surface of the member through which the laser beam L passes, such as the end face  2 Bd of the holder member  2 B or a surface of the member  3 Ba that comes in contact with the holder member  2 B. 
     The reflecting coating  3 Bb functions as the traveling direction changing means similarly to the reflecting coating  3  in the optical probe  10  in  FIG. 1 . The reflecting coating  3 Bb as a reflector is joined to a part of a surface of the holder member  2 B. In the present embodiment, the reflecting coating  3 Bb reflects the laser beam L that travels along the optical axis of the optical fiber  1  after being output, and changes the traveling direction of the laser beam L by approximately 90 degrees. 
     According to the optical probe  10 B, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting coating  3 Bb is arranged without protruding to an outer diameter side of the holder member  2 B, so that it is possible to reduce an outed diameter of the optical probe  10 B. 
     Furthermore, by forming a refractive index profile on the member  3 Ba through which the laser beam L passes, it is possible to collect, diffuse, or collimate the laser beam L. With this configuration, it is possible to control a power profile of the laser beam L in an irradiation target portion, such as an affected area. 
     Fourth Embodiment 
       FIG. 4  is a schematic diagram illustrating an overall configuration of an optical probe according to a fourth embodiment. An optical probe  10 C includes the optical fiber  1 , the holder member  2 B, and a reflecting member  3 C. The optical fiber  1  has the same configuration as the optical fiber in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. 
     The holder member  2 B has the same configuration as the holder member  2 B in  FIG. 3 , and therefore, explanation thereof will be omitted appropriately. The optical fiber  1  is held by the holder member  2 B in the same manner as in the optical probe  10 B in  FIG. 3 . However, in the optical probe  10 C, the distal end surface of the optical fiber  1  protrudes from the end face  2 Bd of the holder member  2 B. 
     The reflecting member  3 C is arranged on the end face  2 Bd of the holder member  2 B. The reflecting member  3 C is configured with a material, such as metal, that reflects the laser beam L. The reflecting member  3 C can be manufactured by, for example, machining by mechanical processing, molding using a die, powder burning or the like. The reflecting member  3 C includes a reflecting surface  3 Ca that is inclined by approximately 45 degrees with respect to the optical axis of the optical fiber  1 . The reflecting member  3 C is fixed to the end face  2 Bd of the holder member  2 B with an adhesive or the like. Meanwhile, a shape formed by the holder member  2 B and the reflecting member  3 C is approximately the same as the shape of the holder member  2  in  FIG. 1 . 
     The reflecting surface  3 Ca functions as the traveling direction changing means similarly to the reflecting coating  3  in the optical probe  10  in  FIG. 1 . The reflecting member  3 C as a reflector is joined to a part of a surface of the holder member  2 B. In the present embodiment, the reflecting surface  3 Ca reflects the laser beam L that travels along the optical axis of the optical fiber  1  after being output, and changes the traveling direction of the laser beam L by approximately 90 degrees. 
     According to the optical probe  10 C, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting member  3 C is arranged without protruding to the outer diameter side of the holder member  2 B, so that it is possible to reduce an outer diameter of the optical probe  10 C. 
     Meanwhile, in the present embodiment, the reflecting member  3 C is made of metal, but it may be possible to arrange, instead of the reflecting member  3 C, a reflecting member that is made with a material, such as glass, resin, ceramic, or plastic, that does not reflect the laser beam L or that has low reflectivity, and that has approximately the same shape as that of the reflecting member  3 C. In this case, it is preferable to arrange, on the reflecting member, an inclined surface that is inclined by approximately 45 degrees with respect to the optical axis of the optical fiber  1 , and arrange a reflecting coating that is made of metal or a dielectric multi-layer on the inclined surface. Furthermore, it may be possible to fix the holder member  2 B and the reflecting member by welding or optical contact that is a method of joining highly-precisely polished surfaces by intermolecular forces, depending on the material of the reflecting member. 
     Manufacturing Method 
     One example of a method of manufacturing the optical probe  10 A according to the second embodiment illustrated in  FIG. 2  will be described below with reference to  FIG. 5 . First, the optical fiber  1  is inserted into the holder member  2 A from the optical fiber input hole  2 Ab and is inserted in the insertion hole  2 Ac, and a relative position of the optical fiber  1  with respect to the holder member  2 A is adjusted while monitoring a position of a distal end of the optical fiber  1  (a distal end of the glass optical fiber  1   a ) in a direction of an arrow A 1 . Then, after the relative position reaches a predetermined position, the holder member  2 A and the optical fiber  1  are fixed to each other. Subsequently, the reflecting member  3 A is fixed to a predetermined position on the holder member  2 A to which the optical fiber  1  is fixed. Here, the predetermined position is a predetermined position inside the opening hole  2 Aa of the holder member  2 A. The predetermined position may be finely adjusted such that an optical path of the reflected laser beam L matches a desired optical path with regard to the relative position with respect to the optical fiber  1 . Furthermore, it may be possible to first fix the member  3 Aa of the reflecting member  3 A to the holder member  2 A, and thereafter arrange the reflecting coating  3 Ab on the member  3 Aa. 
     Next, one example of a method of manufacturing the optical probe  10 B according to the third embodiment illustrated in  FIG. 3  will be described with reference to  FIG. 6 . First, the optical fiber  1  is inserted into the holder member  2 B from the optical fiber input hole  2 Bb and is inserted in the insertion hole  2 Bc, and a relative position of the optical fiber  1  with respect to the holder member  2 B is adjusted while monitoring the position of the distal end of the optical fiber  1  (the distal end of the glass optical fiber  1   a ) in the direction of the arrow A 1 . Then, after the relative position reaches a predetermined position, the holder member  2 B and the optical fiber  1  are fixed to each other. Subsequently, the reflecting member  3 B is fixed to a predetermined position on the holder member  2 B to which the optical fiber  1  is fixed. Here, the predetermined position is a predetermined position on the end face  2 Bd of the holder member  2 B. The predetermined position may be finely adjusted such that the optical path of the reflected laser beam L matches a desired optical path with regard to the relative position with respect to the optical fiber  1 . Furthermore, it may be possible to first fix the member  3 Ba of the reflecting member  3 B to the holder member  2 B, and thereafter arrange the reflecting coating  3 Bb on the member  3 Ba. 
     The optical probes  10  and  10 C according to the first and the fourth embodiments illustrated in  FIGS. 1 and 4  can easily be manufactured in the same manner as the simple manufacturing methods as illustrated in  FIGS. 5 and 6 . 
     Next, another example of the method of manufacturing the optical probe  10 A according to the second embodiment illustrated in  FIG. 2  will be described with reference to  FIG. 7 . First, the reflecting member  3 A is fixed at a predetermined position inside the opening hole  2 Aa of the holder member  2 A. Subsequently, the optical fiber  1  is inserted into the holder member  2 A from the optical fiber input hole  2 Ab and is inserted in the insertion hole  2 Ac, and a relative position of the optical fiber  1  with respect to the holder member  2 A is adjusted while monitoring the position of the distal end of the optical fiber  1  in the direction of the arrow A 1 . Then, after the relative position reaches a predetermined position, the holder member  2 A and the optical fiber  1  are fixed to each other. Meanwhile, the position at which the optical fiber  1  is fixed may be finely adjusted such that the optical path of the reflected laser beam L matches a desired optical path with regard to the relative position with respect to the reflecting member  3 A. 
     The optical probes  10 ,  10 B, and  10 C according to the first, the third, and the fourth embodiments illustrated in  FIGS. 1, 3, and 4  can easily be manufactured in the same manner as the simple manufacturing method as illustrated in  FIG. 7 . 
     Fifth Embodiment 
       FIG. 8  is a schematic diagram illustrating an overall configuration of an optical probe according to a fifth embodiment. An optical probe  10 D includes the optical fiber  1  and a holder member  2 D. The optical fiber  1  has the same configuration as the optical fiber in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. 
     The holder member  2 D is mounted on the distal end side of the optical fiber  1 . The holder member  2 D has an approximately cylindrical outer shape and is made of a material, such as metal, that reflects the laser beam L. A diameter of the holder member  2 D is, for example, approximately 1 to 2 mm or smaller. The holder member  2 D may be manufactured by, for example, machining by mechanical processing, molding using a die, powder burning or the like. 
     The holder member  2 D includes an opening hole  2 Da, an optical fiber input hole  2 Db, and an insertion hole  2 Dc. The optical fiber input hole  2 Db is formed so as to extend from an end face of the holder member  2 D along a cylindrical central shaft of the holder member  2 D or the vicinity of the cylindrical central shaft, and has an approximately constant inner diameter; however, the inner diameter may be gradually reduced. The insertion hole  2 Dc communicates with the optical fiber input hole  2 Db on a distal end side of the optical fiber input hole  2 Db (on the right side in the figure), and is formed so as to extend along the cylindrical central shaft of the holder member  2 D or the vicinity of the cylindrical central shaft. An inner diameter of the insertion hole  2 Dc is slightly larger than the outer diameter of the glass optical fiber  1   a . The opening hole  2 Da communicates with the insertion hole  2 Dc, and is opened on a side surface in a direction in which the insertion hole  2 Dc extends, that is, on a cylindrical outer periphery of the holder member  2 D. 
     The optical fiber  1  is held by the holder member  2 D in the same manner as in the optical probe  10  in  FIG. 1 . 
     In the holder member  2 D, a reflecting surface  2 Dd that forms an inner wall of the opening hole  2 Da is arranged at a position facing the distal end surface of the optical fiber  1 . The reflecting surface  2 Dd is inclined by approximately 45 degrees with respect to the optical axis of the optical fiber  1 . 
     The reflecting surface  2 Dd is a part of the holder member  2 D and is a reflecting portion that reflects the laser beam L 1  output from the optical fiber  1 . In the present embodiment, the traveling direction changing means is configured with the reflecting surface  2 Dd. In other words, in the present embodiment, the reflecting surface  2 Dd reflects the laser beam L that travels along the optical axis of the optical fiber  1  after being output, and changes the traveling direction of the laser beam L by approximately 90 degrees. 
     According to the optical probe  10 D, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting surface  2 Dd is a part of the holder member  2 D, so that it is possible to reduce an outer diameter of the optical probe  10 D and reduce the number of use components. 
     Sixth Embodiment 
       FIG. 9  is a schematic diagram illustrating an overall configuration of an optical probe according to a sixth embodiment. An optical probe  10 E includes the optical fiber  1  and a holder member  2 E. The optical fiber  1  has the same configuration as the optical fiber in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. 
     The holder member  2 E is a member for holding the optical fiber  1 , and is mounted on the distal end side of the optical fiber  1 . The holder member  2 E has an approximately cylindrical outer shape and is made of a material, such as glass, that transmits the laser beam L. A diameter of the holder member  2 E is, for example, approximately 1 to 2 mm or smaller. 
     The holder member  2 E includes an optical fiber input hole  2 Eb, an insertion hole  2 Ec, and a projection portion  2 Ed. The optical fiber input hole  2 Eb is formed so as to extend from an end face of the holder member  2 E on the left side in the figure along a cylindrical central shaft of the holder member  2 E or the vicinity of the cylindrical central shaft, and has a gradually reduced inner diameter. The insertion hole  2 Ec communicates with the optical fiber input hole  2 Eb on a distal end side of the optical fiber input hole  2 Eb (on the right side in the figure), and is formed so as to extend along the cylindrical central shaft of the holder member  2 E or the vicinity of the cylindrical central shaft. An inner diameter of the insertion hole  2 Ec is slightly larger than the outer diameter of the glass optical fiber  1   a . The projection portion  2 Ed is formed, in the holder member  2 E, on an end face opposite to the end face on which the optical fiber input hole  2 Eb is formed. The projection portion  2 Ed has a certain shape, such as a triangular prism or a tetrahedron. 
     The optical fiber  1  is held by the holder member  2 E in the same manner as in the optical probe  10  in  FIG. 1 . 
     The projection portion  2 Ed includes a reflecting surface  2 Ee as one surface thereof. The reflecting surface  2 Ee is inclined by approximately 45 degrees with respect to the optical axis of the optical fiber  1 . 
     The reflecting surface  2 Ee is a part of the holder member  2 E and is a reflecting portion that reflects the laser beam L 1  output from the optical fiber  1 . In the present embodiment, the traveling direction changing means is configured with the reflecting surface  2 Ee. In other words, in the present embodiment, the reflecting surface  2 Ee reflects the laser beam L that travels along the optical axis of the optical fiber  1  after being output, and changes the traveling direction of the laser beam L by approximately 90 degrees. 
     According to the optical probe  10 E, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting surface  2 Ee is a part of the holder member  2 E, so that it is possible to reduce an outer diameter of the optical probe  10 E and reduce the number of use components. 
     Furthermore, by forming a refractive index profile on a portion, such as the projection portion  2 Ed, through which the laser beam L passes in the holder member  2 E, it is possible to collect, diffuse, or collimate the laser beam L. With this configuration, it is possible to control a power profile of the laser beam L in an irradiation target portion, such as an affected area. 
     Manufacturing Method 
     One example of a method of manufacturing the optical probe  10 D according to the fifth embodiment illustrated in  FIG. 8  will be described with reference to  FIG. 10 . First, the optical fiber  1  is inserted into the holder member  2 D from the optical fiber input hole  2 Db and is inserted in the insertion hole  2 Dc, and the relative position of the optical fiber  1  with respect to the holder member  2 D is adjusted while monitoring the position of the distal end of the optical fiber  1  (the distal end of the glass optical fiber  1   a ) in the direction of the arrow A 1 . Then, after the relative position reaches a predetermined position, the holder member  2 D and the optical fiber  1  are fixed to each other. Meanwhile, the position at which the optical fiber  1  is fixed may be finely adjusted such that the optical path of the reflected laser beam L matches a desired optical path with regard to the relative position with respect to the reflecting surface  2 Dd. 
     The optical probe  10 E according to the sixth embodiment illustrated in  FIG. 9  can easily be manufactured in the same manner as the simple manufacturing method as illustrated in  FIG. 10 . 
     Shape of Reflecting Surface 
     Here, the shape of the reflecting surface in each of the embodiments will be described. The reflecting surface for the laser beam L in each of the embodiments above and below is illustrated as a flat surface like a reflecting surface R 1  in  FIG. 11A , but may have a concave shape like a reflecting surface R 2  in  FIG. 11B  or may have a convex shape like a reflecting surface R 3  in  FIG. 11C . In the case of the concave shape and the convex shape, a spherical shape, a paraboloidal shape, or other shapes may be adopted. By setting the shape of the reflecting surface as described above, it is possible to collect, diffuse, or collimate the laser beam L. With this configuration, it is possible to control a power profile of the laser beam L in an irradiation target portion, such as an affected area. 
     Seventh Embodiment 
       FIG. 12A  and  FIG. 12B  are schematic diagrams illustrating an overall configuration of an optical probe according to a seventh embodiment. As illustrated in  FIG. 12A , the optical probe  10 F includes an optical fiber  1 F, a holder member  2 F, and the reflecting coating  3 . 
     As illustrated in  FIG. 12A  and  FIG. 12B , the optical fiber  1 F includes a glass optical fiber  1 Fa having a core portion  1 Faa and a cladding portion  1 Fab, and a covering  1 Fb that is formed on an outer circumference of the glass optical fiber  1 Fa. In the optical fiber  1 F, the covering  1 Fb is removed on a distal end side, and a predetermined length of the glass optical fiber  1 Fa is exposed. The optical fiber  1 F has the same configuration as the optical fiber  1  except that a distal end surface  1 Fac from which the laser beam L is output is inclined with respect to an optical axis of the optical fiber  1 F, that is, with respect to an optical axis of the glass optical fiber  1 Fa, and therefore, explanation thereof will be omitted appropriately. In the optical fiber  1 F, the distal end surface  1 Fac is inclined, so that the laser beam L is output in an inclined direction with respect to the optical axis of the optical fiber  1 F in accordance with an inclination angle. Meanwhile, the distal end surface  1 Fac is inclined by approximately 10 degrees with respect to a plane perpendicular to the optical axis of the optical fiber  1 F. The inclination angle as described above can easily be formed by a fiber cutter, mechanical polishing, chemical etching or the like. 
     The holder member  2 F is mounted on a distal end side of the optical fiber  1 F. The holder member  2 F includes an opening hole  2 Fa, an optical fiber input hole  2 Fb, and an insertion hole  2 Fc. The opening hole  2 Fa, the optical fiber input hole  2 Fb and the insertion hole  2 Fc have the same configurations as the opening hole  2   a,  the optical fiber input hole  2   b,  and the insertion hole  2   c,  respectively, illustrated in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. 
     The optical fiber  1  is held by the holder member  2 A in the same manner as in the optical probe  10  in  FIG. 1 . 
     The holder member  2 F includes an inclined surface  2 Fd at a position facing the distal end surface  1 Fac of the optical fiber  1 F inside the opening hole  2 Fa. The reflecting coating  3  as a reflector is arranged on the inclined surface  2 Fd. The inclined surface  2 Fd and the reflecting surface of the reflecting coating  3  are inclined by a predetermined angle with respect to the optical axis of the optical fiber  1 F. 
     The reflecting coating  3  functions as the traveling direction changing means that changes the traveling direction of the laser beam L output from the optical fiber  1 F to a sideward direction with respect to the optical fiber  1 F. In the present embodiment, the reflecting coating  3  reflects the laser beam L that travels in an inclined direction with respect to the optical axis of the optical fiber  1 F after being output, and changes the traveling direction of the laser beam L such that the traveling direction forms an angle of approximately 90 degrees with the optical axis of the optical fiber  1 F. To realize this, the inclination angle of the inclined surface  2 Fd is set to be a gradual inclination angle as compared to the inclined surface  2   d  of the holder member  2  in  FIG. 1 . 
     According to an optical probe  10 F, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting coating  3  is arranged inside the opening hole  2 Fa without protruding to an outer diameter side of the holder member  2 F, so that it is possible to reduce an outer diameter of the optical probe  10 F. 
     Eighth Embodiment 
       FIG. 13  is a schematic diagram illustrating an overall configuration of an optical probe according to an eighth embodiment. An optical probe  10 G has a configuration that is obtained by, in the configuration of the optical probe  10 A in  FIG. 2 , replacing the optical fiber  1  with the optical fiber  1 F and replacing the reflecting member  3 A with a reflecting member  3 G. 
     The reflecting member  3 G is arranged at a position facing the distal end surface of the optical fiber  1 F inside the opening hole  2 Aa. The reflecting member  3 G includes a member  3 Ga that is made of glass or the like and that has a certain shape, such as a triangular prism or a tetrahedron, and a reflecting coating  3 Gb that is arranged on one surface of the member  3 Ga. The reflecting coating  3 Gb functions as the traveling direction changing means that changes the traveling direction of the laser beam L output from the optical fiber  1 F to a sideward direction with respect to the optical fiber  1 F. In the present embodiment, the reflecting coating  3 Gb reflects the laser beam L that travels in an inclined direction with respect to the optical axis of the optical fiber  1 F after being output, and changes the traveling direction of the laser beam L such that the traveling direction forms an angle of approximately 90 degrees with the optical axis of the optical fiber  1 F. To realize this, an inclination angle of the reflecting coating  3 Gb is set to be a gradual inclination angle as compared to the reflecting coating  3 Ab in  FIG. 2 . 
     According to the optical probe  10 F, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, a reflecting coating  3 Fb is arranged inside the opening hole  2 Aa without protruding to the outer diameter side of the holder member  2 A, so that it is possible to reduce an outer diameter of the optical probe  10 F. 
     Ninth Embodiment 
       FIG. 14  is a schematic diagram illustrating an overall configuration of an optical probe according to a ninth embodiment. An optical probe  10 H includes the optical fiber  1 F, a holder member  2 H, and a diffraction grating plate  3 H. 
     The holder member  2 H is mounted on the distal end side of the optical fiber  1 F. The holder member  2 H has an approximately cylindrical outer shape and is made of glass in the present embodiment, but a constituent material is not limited to glass as long as it transmits the laser beam L at desired transmissivity. A diameter of the holder member  2  is, for example, approximately 1 to 2 mm or smaller. 
     The holder member  2 H includes an opening hole  2 Ha, an optical fiber input hole (not illustrated), and an insertion hole (not illustrated). The optical fiber input hole and the insertion hole respectively have the same configurations as the optical fiber input hole  2   b  and the insertion hole  2   c  in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. The opening hole  2 Ha communicates with the insertion hole, and is opened on a side surface in a direction in which the insertion hole extends, that is, on a cylindrical outer periphery of the holder member  2 H. 
     The holder member  2 H includes an inclined surface  2 Hd at a position facing the distal end surface  1 Fac of the optical fiber  1 F in the opening hole  2 Ha. The optical fiber  1 F is held by the holder member  2 A in the same manner as in the optical probe  10  in  FIG. 1  such that the distal end surface  1 Fac of the optical fiber  1 F comes into contact with the inclined surface  2 Hd. It is preferable to form an antireflection coating for the laser beam L on the inclined surface  2 Hd. 
     Further, the holder member  2 H includes an inclined surface  2 He as a distal end surface on the right side in the figure. The inclined surface  2 Hd and the inclined surface  2 He are inclined in different directions, and a cross section of a distal end portion  2 Hf of the holder member  2 H has a trapezoidal shape. 
     The diffraction grating plate  3 H is arranged on the inclined surface  2 He. In the present embodiment, the diffraction grating plate  3 H is a transmissive type. It is preferable to form an antireflection coating for the laser beam L on a surface of a member, such as the inclined surface  2 He of the holder member  2 H or a surface that comes into contact with the holder member  2 H of the diffraction grating plate  3 H, through which the laser beam L passes. 
     The diffraction grating plate  3 H functions as the traveling direction changing means that changes the traveling direction of the laser beam L output from the optical fiber  1 F to a sideward direction with respect to the optical fiber  1 F. Specifically, in the present embodiment, the diffraction grating plate  3 H diffracts the laser beam L that travels in an inclined direction with respect to an optical axis of the optical fiber  1 F after being output, and changes the traveling direction such that the traveling direction forms an angle of approximately 90 degrees with the optical axis of the optical fiber  1 F. In the present embodiment, arrangement orientation of a diffraction grating in the diffraction grating plate  3 H is set so as to be parallel to a plane formed by the optical paths of the laser beam L before and after being output from the optical fiber  1 F. 
     According to the optical probe  10 H, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the diffraction grating plate  3 H is arranged so as not to protrude to an outer diameter side of the holder member  2 H, so that it is possible to reduce an outer diameter of the optical probe  10 H. 
     Manufacturing Method 
     One example of a method of manufacturing the optical probe  10 F according to the seventh embodiment illustrated in  FIG. 12A  and  FIG. 12B  will be described below with reference to  FIG. 15 . First, the optical fiber  1 F is inserted into the holder member  2 F from the optical fiber input hole  2 Fb and is inserted in the insertion hole  2 Fc, and a relative position of the optical fiber  1 F with respect to the holder member  2 F is adjusted. Subsequently, after the relative position reaches a predetermined position, rotational alignment is performed by rotating the optical fiber  1 F about an axis of the holder member  2 F while monitoring a distal end of the optical fiber  1 F in the direction of the arrow A 1 . The distal end surface  1 Fac of the optical fiber  1 F is inclined, and therefore may serve as a positioning key in the rotational alignment. Further, at the same time or after the rotational alignment, it may be possible to finely adjust the relative position of the optical fiber  1 F with respect to the holder member  2 F such that the optical path of the laser beam L matches a desired optical path. After completion of the rotational alignment and the fine adjustment, the holder member  2 F and the optical fiber  1 F are fixed to each other. 
     The optical probe  10 G according to the eighth embodiment illustrated in  FIG. 13  can easily be manufactured in the same manner as the simple manufacturing method as illustrated in  FIG. 15 . Further, as for a method of manufacturing the optical probe  10 H according to the ninth embodiment illustrated in  FIG. 14 , for example, the rotational alignment is first performed on the optical fiber  1 F, and the distal end surface  1 Fac and the inclined surface  2 Hd of the holder member  2 H are brought into contact with each other in a parallel manner. At this time, the distal end surface  1 Fac and the inclined surface  2 Hd may be bonded together. Accordingly, a rotation position of the distal end surface  1 Fac is fixed. Thereafter, it is sufficient to determine a position of the diffraction grating plate  3 H at a predetermined position on the inclined surface  2 He and fix the diffraction grating plate  3 H at this position. 
     Tenth Embodiment 
       FIG. 16A  and  FIG. 16B  are schematic diagrams illustrating an overall configuration of an optical probe according to a tenth embodiment. As illustrated in  FIG. 16A , an optical probe  10 I includes the optical fiber  1 , a holder member  2 I, and the reflecting member  3 B. 
     The holder member  2 I includes an optical fiber input hole  2 Ib, an insertion hole  2 Ic, a diameter extending hole  2 Ie, and an end face  2 Id. The optical fiber input hole  2 Ib and the insertion hole  2 Ic respectively have the same configurations as the optical fiber input hole  2 Bb and the insertion hole  2 Bc of the holder member  2 B illustrated in  FIG. 3 , and therefore, explanation thereof will be omitted appropriately. The diameter extending hole  2 Ie is arranged on the end face  2 Id of the holder member  2 I located on the right side in the figure, and communicates with the insertion hole  2 Ic. The diameter extending hole  2 Ie has a larger inner diameter than the insertion hole  2 Ic. Specifically, the diameter extending hole  2 Ie is formed such that the inner diameter is gradually increased from the side communicating with the insertion hole  2 Ic toward the end face  2 Id. The reflecting member  3 B is arranged on the end face  2 Id of the holder member  2 I similarly to the case illustrated in  FIG. 3 . A configuration and functions of the reflecting member  3 B are the same as those of the third embodiment illustrated in  FIG. 3 , and therefore, explanation thereof will be omitted appropriately. 
     Here, as illustrated in  FIG. 16A  and  FIG. 16B , the distal end surface of the optical fiber  1  is located at the side of the optical fiber input hole  2 Ib relative to the end face  2 Id of the holder member  2 I, and is located at a boundary of the insertion hole  2 Ic and the diameter extending hole  2 Ie or at the side of the diameter extending hole  2 Ie relative to the boundary. In the present embodiment, specifically, the distal end surface is located at the side of the diameter extending hole  2 Ie relative to the boundary. As illustrated in  FIG. 16B , the glass optical fiber  1   a  includes a core portion  1   aa  and a cladding portion  1   ab , and a beam diameter of the laser beam L is extended after the laser beam L is output from the core portion  1   aa . The diameter extending hole  2 Ie functions to prevent the laser beam L from being blocked by the holder member  2 I even if the beam diameter of the laser beam L is extended as described above. Therefore, an inner diameter of the diameter extending hole  2 Ie is set to a certain inner diameter such that the laser beam L is not blocked by the holder member  2 I by taking into account NA (the number of openings) of the glass optical fiber  1   a , a distance between the distal end surface of the glass optical fiber  1   a  and the end face  2 Id or the like. 
     Eleventh Embodiment 
       FIG. 17  is a schematic diagram illustrating an overall configuration of an optical probe according to an eleventh embodiment. The optical probe according to the eleventh embodiment is obtained by replacing the holder member  2 I with a holder member  2 J in the optical probe  10 I according to the tenth embodiment illustrated in  FIG. 16B . In the holder member  2 J, a diameter extending hole  2 Je is arranged on an end face  2 Jd of the holder member  2 J and communicates with an insertion hole  2 Jc. The diameter extending hole  2 Je has an inner diameter that is larger than that of the insertion hole  2 Jc and that is approximately constant in an extending direction of the diameter extending hole  2 Je. The diameter extending hole  2 Je functions to prevent the laser beam L whose beam diameter is extended after being output from the core portion  1   aa  from being blocked by the holder member  2 J, and the inner diameter is set to implement this function. 
     Twelfth Embodiment 
       FIG. 18  is a schematic diagram illustrating an overall configuration of an optical probe according to a twelfth embodiment. As illustrated in  FIG. 18 , an optical probe  10 K includes an optical fiber  1 K and a reflecting coating  3 K. 
     The optical fiber  1 K includes a glass optical fiber  1 Ka having a core portion  1 Kaa and a cladding portion  1 Kab, and a covering  1 Kb that is formed on an outer circumference of the glass optical fiber  1 Ka. In the optical fiber  1 K, the covering  1 Kb is removed on a distal end side, and a predetermined length of the glass optical fiber  1 Ka is exposed. The optical fiber  1 K has the same configuration as the optical fiber  1  except that a distal end surface  1 Kac from which the laser beam L is output is inclined with respect to an optical axis of the optical fiber  1 K, that is, an optical axis of the glass optical fiber  1 Ka, and therefore, explanation thereof will be omitted appropriately. The distal end surface  1 Kac is inclined by approximately 45 degrees with respect to a plane perpendicular to the optical axis of the optical fiber  1 K. The inclination angle as described above can easily be formed by a fiber cutter, mechanical polishing, chemical etching or the like. 
     The reflecting coating  3 K as a reflector is arranged on the distal end surface  1 Kac. The reflecting coating  3 K is configured with a metal film, a dielectric multi-layer or the like. The reflecting coating  3 K functions as the traveling direction changing means that changes the traveling direction of the laser beam L output from the optical fiber  1 K to a sideward direction with respect to the optical fiber  1 K. In the present embodiment, the reflecting coating  3 K reflects the laser beam L, and changes the traveling direction of the laser beam L by approximately 90 degrees. 
     According to the optical probe  10 K, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting coating  3 K is arranged on the distal end surface  1 Kac of the optical fiber  1 K, so that it is possible to reduce an outer diameter of the optical probe  10 K and reduce the number of use components. 
     Thirteenth Embodiment 
       FIG. 19A  and  FIG. 19B  are schematic diagrams illustrating an overall configuration of an optical probe according to a thirteenth embodiment. As illustrated in  FIG. 19A  and  FIG. 19B , an optical probe  10 KA is configured by inserting the optical fiber  1 K of the optical probe  10 K of the twelfth embodiment from the optical fiber input hole  2 Ab of the holder member  2 A illustrated in  FIG. 2 , inserting the optical fiber  1 K in the insertion hole  2 Ac such that the distal end protrudes to the inside of the opening hole  2 Aa, and fixing the optical fiber  1 K to the holder member  2 A. As illustrated in  FIG. 19B , in the optical fiber  1 K, the distal end surface  1 Kac of the optical fiber  1 K is oriented to a side opposite to the opening side of the opening hole  2 Aa. With this configuration, the reflecting coating  3 K reflects the laser beam L, changes the traveling direction of the laser beam L by approximately 90 degrees, and outputs the laser beam L from the opening hole  2 Aa. 
     According to the optical probe  10 KA, it is possible to change the traveling direction of the laser beam L with a simple, small, and easily manufacturable configuration. In particular, the reflecting coating  3 K is arranged on the distal end surface  1 Kac of the optical fiber  1 K, so that it is possible to reduce an outer diameter of the optical probe  10 KA and reduce the number of use components. Further, it is possible to protect the distal end surface of the optical fiber  1 K by the holder member  2 A. 
     Manufacturing Method 
     One example of a method of manufacturing the optical probe  10 K according to the thirteenth embodiment illustrated in  FIG. 19A  and  FIG. 19B  will be described below with reference to  FIG. 20 . First, the optical fiber  1 K is inserted into the holder member  2 A from the optical fiber input hole  2 Ab and is inserted in the insertion hole  2 Ac, and a relative position of the optical fiber  1 K with respect to the holder member  2 A is adjusted. Subsequently, after the relative position reaches a predetermined position, the rotational alignment is performed by rotating the optical fiber  1 K about the axis of the holder member  2 A while monitoring a distal end of the optical fiber  1 K in the direction of the arrow A 1 . The distal end surface  1 Kac of the optical fiber  1 K is inclined, and therefore serves as a positioning key in the rotational alignment. Further, at the same time or after the rotational alignment, it may be possible to finely adjust the relative position of the optical fiber  1 K with respect to the holder member  2 A such that the optical path of the laser beam L matches a desired optical path. After completion of the rotational alignment and the fine adjustment, the holder member  2 A and the optical fiber  1 K are fixed to each other. 
     Configuration Examples of Optical Fiber 
     Meanwhile, in the optical probe according to each of the embodiments as described above, in some cases, a monitoring beam with a wavelength different from that of the laser beam L may be input in addition to the laser beam L from a proximal end side of the optical fiber in order to detect flexure or bend of the optical fiber that transmits the laser beam L. In this case, it is desirable to provide, on the distal end side of the optical fiber, a reflecting mechanism that reflects the monitoring beam transmitted in the optical fiber to the proximal end side. Configuration examples of the optical fiber including the reflecting mechanism as described above will be described below. 
     First Configuration Example 
       FIG. 21  is a schematic diagram illustrating an overall configuration of a first configuration example of an optical fiber. An optical fiber  1 L includes a glass optical fiber  1 La having a core portion  1 Laa and a cladding portion  1 Lab, and a covering  1 Lb that is formed on an outer circumference of the glass optical fiber  1 La. In the optical fiber  1 L, the covering  1 Lb is removed on a distal end side, and a predetermined length of the glass optical fiber  1 La is exposed. The glass optical fiber  1 La has the same configuration as the glass optical fiber  1   a  illustrated in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. 
     A reflecting coating  1 Ld as a reflector is arranged on a distal end surface  1 Lac of the glass optical fiber  1 La. The reflecting coating  1 Ld is, for example, a dielectric multi-layer. 
     The optical fiber  1 L transmits the laser beam L 1  in the glass optical fiber  1 La. The laser beam L 1  is, for example laser beam for cautery. Further, the optical fiber  1 L transmits monitoring beam L 2  in the glass optical fiber  1 La. A wavelength of the monitoring beam L 2  is different from a wavelength of the laser beam L 1 , and is separated by, for example, 3 nm or more. For example, the wavelength of the laser beam L 1  belongs to the 980-nm wavelength range, and the monitoring beam L 2  belongs to the visible region, the O band, or the C band. The O band is, for example, a wavelength range of 1260 nm to 1360 nm. The C band is, for example, a wavelength range of 1530 nm to 1565 nm. 
     Here, the reflecting coating  1 Ld transmits the laser beam L 1 . Accordingly, the laser beam L 1  is output by being transmitted through the reflecting coating  1 Ld. In contrast, the reflecting coating  1 Ld reflects the monitoring beam L 2  to the proximal end side. Accordingly, the monitoring beam L 2  is output from the proximal end side, and is used to detect flexure or bend of the optical fiber  1 L. It is preferable to set reflectivity of the reflecting coating  1 Ld with respect to the monitoring beam L 2  to 4% or higher, and it is more preferable to set the reflectivity to 40% or higher. 
     The optical fiber  1 L is configured in an integrated manner with the reflecting coating  1 Ld that serves as a reflecting mechanism, and therefore is configured with a small size. The optical fiber  1 L as described above can be used instead of the optical fiber  1  of the embodiment as described above, for example. 
     Second Configuration Example 
       FIG. 22  is a schematic diagram illustrating an overall configuration of a second configuration example of an optical fiber. An optical fiber  1 M includes a glass optical fiber  1 Ma having a core portion  1 Maa and a cladding portion  1 Mab, and a covering  1 Mb that is formed on an outer circumference of the glass optical fiber  1 Ma. In the optical fiber  1 M, the covering  1 Mb is removed on a distal end side, and a predetermined length of the glass optical fiber  1 Ma is exposed. The glass optical fiber  1 Ma has the same configuration as the glass optical fiber  1   a  illustrated in  FIG. 1 , and therefore, explanation thereof will be omitted appropriately. 
     A Bragg grating G as a reflector is arranged in the core portion  1 Maa on the distal end side of the glass optical fiber  1 Ma. The Bragg grating G is configured such that a refractive index is periodically changed along a longitudinal direction of the core portion  1 Maa. 
     The optical fiber  1 M transmits the laser beam L 1  and the monitoring beam L 2  in the glass optical fiber  1 Ma. Here, the Bragg grating G transmits the laser beam L 1 . Accordingly, the laser beam L 1  is output by being transmitted through the Bragg grating G. In contrast, the Bragg grating G reflects the monitoring beam L 2  to the proximal end side. Accordingly, the monitoring beam L 2  is output from the proximal end side and can be used to detect flexure or bend of the optical fiber  1 M. It is preferable to set reflectivity of the Bragg grating G with respect to the monitoring beam L 2  to 4% or higher, and it is more preferable to set the reflectivity to 40% or higher. 
     The optical fiber  1 M incorporates therein the Bragg grating G that serves as a reflecting mechanism, and therefore is configured with a small size. The optical fiber  1 M as described above can be used instead of the optical fiber  1  of the embodiments as described above, for example. 
     Fourteenth Embodiment 
     A configuration for reflecting a beam using the Bragg grating can preferably be applied to a configuration in which a distal end surface of an optical fiber is inclined.  FIG. 23  is a schematic diagram illustrating an overall configuration of an optical probe according to a fourteenth embodiment. An optical probe  10 N includes an optical fiber  1 N and the reflecting coating  3 K. 
     The optical fiber  1 N includes a glass optical fiber  1 Na having a core portion  1 Naa and a cladding portion  1 Nab, and a covering  1 Nb that is formed on an outer circumference of the glass optical fiber  1 Na. In the optical fiber  1 N, the covering  1 Nb is removed on a distal end side, and a predetermined length of the glass optical fiber  1 Na is exposed. The optical fiber  1 N has the same configuration as the optical fiber  1 M except that a distal end surface  1 Nac from which the laser beam L 1  is output is inclined with respect to an optical axis of the optical fiber  1 N, that is, an optical axis of the glass optical fiber  1 Na, and therefore, explanation thereof will be omitted appropriately. In other words, the Bragg grating G as a reflector is arranged in the core portion  1 Naa on the distal end side of the glass optical fiber  1 Na. Meanwhile, the distal end surface  1 Nac is inclined by approximately 45 degrees with respect to a plane perpendicular to an optical axis of the optical fiber  1 N, and includes the reflecting coating  3 K as a reflector. 
     The optical fiber  1 N transmits the laser beam L 1  and the monitoring beam L 2  in the glass optical fiber  1 Na. Here, the Bragg grating G transmits the laser beam L 1 . Accordingly, the laser beam L 1  is output by being transmitted through the Bragg grating G. The reflecting coating  3 K reflects the laser beam L 1  output from the optical fiber  1 N, and changes the traveling direction of the laser beam L by approximately 90 degrees. 
     In contrast, the Bragg grating G reflects the monitoring beam L 2  to the proximal end side. Accordingly, the monitoring beam L 2  is output from the proximal end side and can be used to detect flexure and bend of the optical fiber  1 N. 
     Third Configuration Example 
       FIG. 24  is a schematic diagram illustrating an overall configuration of a third configuration example of the optical fiber. An optical fiber  1 P includes a glass optical fiber  1 Pa having a core portion  1 Paa and a cladding portion  1 Pab, and a covering  1 Pb that is formed on an outer circumference of the glass optical fiber  1 Pa. In the optical fiber  1 P, the covering  1 Pb is removed on a distal end side, and a predetermined length of the glass optical fiber  1 Pa is exposed. 
     A reflecting coating  1 Pd as a reflector is arranged on a distal end surface  1 Pac of the glass optical fiber  1 Pa. The reflecting coating  1 Pd is, for example, a dielectric multi-layer. The Bragg grating G as a reflector is arranged in the core portion  1 Paa on the distal end side of the glass optical fiber  1 Pa. 
     The optical fiber  1 P transmits the laser beam L 1 , the monitoring beam L 2 , and monitoring beam L 3  in the glass optical fiber  1 Pa. A wavelength of the monitoring beam L 3  is different from the wavelength of the laser beam L 1 , and is separated by, for example, 3 nm or more. Further, the wavelength of the monitoring beam L 3  is also different from the wavelength of the monitoring beam L 2 . For example, the wavelength of the laser beam L 1  belongs to the 980-nm wavelength range, and the monitoring beam L 3  belongs to the visible region, the O band, or the C band. 
     The Bragg grating G and the reflecting coating  1 Pd transmit the laser beam L 1 . Accordingly, the laser beam L 1  is output by being transmitted through the Bragg grating G and the reflecting coating  1 Pd. In contrast, the Bragg grating G transmits the monitoring beam L 3  and reflects the monitoring beam L 2  to the proximal end side. In contrast, the reflecting coating  1 Pd reflects the monitoring beam L 3  to the proximal end side. Accordingly, the monitoring beam L 2  and L 3  are output from the proximal end side and can be used to detect flexure or bend of the optical fiber  1 P. 
     The optical fiber  1 P is configured in an integrated manner with the Bragg grating G and the reflecting coating  1 Pd that serve as reflecting mechanisms, and therefore is configured with a small size. The optical fiber  1 P as described above can be used instead of the optical fiber  1  of the embodiments as described above. 
     Meanwhile, the configuration of the optical fiber including the reflecting mechanism is not limited to the configuration examples as described above, but it may be possible to include, in the core portion, a plurality of Bragg gratings that reflect different wavelengths. Further, it may be possible to form reflecting coatings with characteristics that reflect different wavelengths on a distal end surface of an optical fiber. 
     Furthermore, in the optical probe according to each of the embodiments as described above, the traveling direction of the laser beam output from the optical fiber is changed by approximately 90 degrees, but the changed traveling direction of a beam is not limited to 90 degrees but may be, for example, in a range of 45 degrees to 135 degrees with respect to the optical axis of the optical fiber. 
     Moreover, in the optical probe according to each of the embodiments as described above, it may be possible to input what is called an aiming beam from the proximal end side of the optical fiber in the optical probe in order to check a position, such as an affected area, to be irradiated with the laser beam L. As the aiming beam, in general, a visible beam is used. The aiming beam is output from the distal end of the optical fiber similarly to the laser beam L. 
     The present disclosure is not limited by the embodiments as described above. The present disclosure includes configurations that are obtained by appropriately combining constituent elements of each of the embodiments as described above. Furthermore, additional effects and modifications may be easily derived by a person skilled in the art. Therefore, broader aspects of the present disclosure are not limited to the embodiments as described above, and various modifications may be made. 
     Industrial Applicability 
     An optical probe according to the present disclosure is useful for an optical probe on a distal end side of an optical fiber that is used in a catheter to be inserted into a body of a patient. 
     According to an embodiment, it is possible to realize an optical probe capable of changing a traveling direction of an output beam to a sideward direction.