JP2009254873A - Method for manufacturing fiberscope with thin diameter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming an end of a fiberscope with thin diameter, preventing an object surface of an object lens from being polished for preventing deterioration of optical characteristics of the object lens. <P>SOLUTION: In a fixing process, an inner tube 5 and a light guide fiber 1 having hollow cylindrical form are put together along the length, adhesive agent is applied for a predetermined length, and they are inserted to an outer component 3 to be fixed. In a polishing process, chips of the light guide fiber 1 and the inner tube 5 protruded from the outside component 3 are polished perpendicularly to the length direction. In an insertion process, an image fiber 7 as the object lens 9 connected to the inner tube 5 is inserted after polishing. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a thin fiberscope used for observing a narrow part in a medical field or industrial application.

  In image guides and light guides constituting a fiberscope, a method of assembling an objective lens to a base in an end portion forming process is generally used.

  However, in recent years, there has been a demand for a small-diameter fiberscope having a small diameter for applications such as a blood vessel endoscope. As such a technique, end processing without a base is required, such as “Ultra-fine diameter medical fiberscope” (Mitsubishi Cable Industrial Time Report), “Medical ultra-thin image fiber and its application” (Fujikura technique), etc. In addition, the one using a resin tube for the end cover has come to be used.

  In the conventional structure using the base, the main parts such as the image guide and the light guide can be finished by incorporation, but the new structure as described above seems to require polishing in the end face finishing process. It has become.

  As a method for polishing the objective lens of such a thin fiberscope, for example, the method described in Patent Document 1 as shown in FIG. 6 has already been proposed.

  In this thin fiberscope 100, an image fiber 102 and an objective lens 103 are incorporated into a longitudinal lumen (hole) 101a of a light guide fiber 101, and the light guide fiber 101, the image fiber 102, and the objective lens 103 are integrated at one end thereof. A branching portion 104 having an opening 101b is provided in the middle of the light guide fiber 101, the image fiber 102 is branched therefrom, and the tip of the branching side is used as an image output unit, and the imaging unit of the naked eye or camera , And the other end of the light guide fiber 101 is opposed to the light source 105 as an illumination light introduction port.

  The outer diameter of the thin fiberscope 100 is small, and in recent years, those having a diameter of less than 1 mm have been provided.

  By the way, the periphery of the distal end portion 107 of such a thin fiberscope 100 has a structure as shown in FIG. 7B, and FIG. 7A is a view showing a manufacturing method thereof.

  That is, in the conventional method for manufacturing the thin fiberscope 100, the light guide fiber 101 and the image fiber 102 are inserted into the exterior portion 106 made of a cylindrical metal immediately after the adhesive is applied, and the adhesive is dried. At this stage, the surplus length portion 108 is gradually polished in the polishing process, and finally the objective lens 103 is polished to the boundary line AA between the surplus length portion 108 and the tip end portion 107. The object surface 109 is to be exposed.

JP-A-10-197805

  However, in the conventional manufacturing method of the thin fiberscope 100, as shown in FIG. 7C, the cross section of the exterior portion 106 and the objective surface 109 appear after polishing, but some polishing is performed in the polishing process. After that, a part 110a with good optical characteristics and a part 110b with poor optical characteristics are mixed on the surface of the objective surface 109 of the objective lens 103. As a result, an image formed by the variation of the focal position is obtained. There has been a problem that optical characteristic changes such as partial blurring occur.

  Therefore, there has been a demand for a manufacturing method with good optical characteristics for the objective surface 109 of the objective lens 103.

  The present invention has been made in view of the above. As an object of the present invention, an end of a thin fiberscope that can prevent the objective surface of the objective lens from being polished and the optical characteristics of the objective lens from deteriorating can be prevented. It is to provide a method for forming a part.

  In order to solve the above-mentioned problem, the first invention provides a light guide fiber that propagates irradiation light to irradiate an object and an image fiber that receives reflected light from the object with an objective lens and propagates the light. A method for manufacturing a thin fiberscope that is inserted into and secured to a cylindrical hollow provided in a diameter exterior portion, and the inner tube having a hollow cylindrical shape and the light guide fiber are aligned and bonded in the longitudinal direction. A fixing step of applying an agent for a predetermined length and inserting and fixing the agent into the exterior portion; a polishing step of polishing the light guide fiber protruding from the exterior portion and the tip portion of the inner tube at right angles to the longitudinal direction; The gist of the present invention is to have an insertion step of inserting an image fiber in which an objective lens is fusion-connected into the hollow of the inner tube later.

  According to a second aspect of the present invention, in order to solve the above-described problem, the polishing step is performed after the opening hole provided in the distal end portion of the inner tube is inserted in advance after inserting a long dummy member having an outer diameter smaller than the opening hole. Then, the gist is to remove the dummy member after polishing.

  In order to solve the above-mentioned problem, the third invention includes a light guide fiber that propagates irradiation light to irradiate an object, and an image fiber that receives reflected light from the object by an objective lens and propagates the light. A method of manufacturing a thin fiberscope that is inserted into and fixed to an outer sheath portion having a diameter, wherein a dome-shaped resin is formed on the objective surface of the objective lens, and the dome-shaped resin is formed A fixing process in which an image fiber having an objective lens and the light guide fiber are aligned in the longitudinal direction and an adhesive is applied for a predetermined length from a tip portion and inserted into an exterior portion and fixed; and the fixed image fiber and light The guide fiber is attached to the objective surface of the objective lens after polishing by polishing the tip portion of the objective lens from the objective surface of the objective lens at right angles to the longitudinal direction. And summarized in that and a peeling step of peeling the that the resin layer.

  In order to solve the above problems, the fourth invention is summarized in that the dome shape forming step uses a resin made of a material that does not harden for forming the dome shape.

  According to the first invention, the inner tube having a hollow cylindrical shape and the light guide fiber are aligned in the longitudinal direction, the adhesive is applied for a predetermined length, and is inserted and fixed to the exterior part. The protruding light guide fiber and the tip of the inner tube are polished at a right angle to the longitudinal direction, and after polishing, the image fiber with the objective lens fused and connected to the hollow of the inner tube is inserted, so the objective surface of the objective lens is polished. This can prevent the deterioration of the optical characteristics of the objective lens.

  According to the second invention, the opening hole provided in the distal end portion of the inner tube is polished after inserting a dummy member having an outer diameter smaller than the opening hole in advance, and the dummy member is removed after polishing. Thus, it is possible to prevent dust such as abrasives and polishing debris from entering the scope from the opening hole of the inner tube to be inserted, and it is possible to prevent the opening hole of the inner tube from being deformed.

  According to the third invention, a dome-shaped resin is formed on the objective surface of the objective lens, and the image fiber having the objective lens on which the dome-shaped resin is formed and the light guide fiber are aligned and bonded in the longitudinal direction. Apply the agent from the tip part for a predetermined length and insert it into the exterior part to fix it, and polish the tip part from the objective surface of the objective lens at right angles to the longitudinal direction for the fixed image fiber and light guide fiber, Since the resin layer adhering to the objective surface of the objective lens is peeled after polishing, it is possible to prevent the objective surface of the objective lens from being polished and to prevent the optical characteristics of the objective lens from being deteriorated.

  According to the fourth invention, by using a resin made of an uncured material for forming the dome shape, the resin layer attached to the objective surface of the objective lens after polishing can be peeled off. Can be prevented, and deterioration of the optical characteristics of the objective lens can be prevented.

(A) is sectional drawing which shows the adhering process which adheres the light guide fiber 1 and the inner tube 5 to the exterior part 3, (b) is sectional drawing which shows a mode that the extra length part 12 was grind | polished to boundary line AA. (C) is a cross-sectional view showing that the objective lens 9 is attached to the tip of the image fiber 7, (d) is a side cross-sectional view of the thin fiberscope, and (e) is a thin fiberscope. It is a figure which shows the mode of this objective surface. In embodiment of this invention, (a) is sectional drawing which shows the dome formation process which forms resin in the objective surface of the objective lens 9, and forms the dome shape 21, (b) is the light guide fiber 1 and dome shape. 7 is a cross-sectional view showing a fixing process for fixing the image fiber 7 to which the objective lens 9 having 21 formed thereon is fixed to the exterior part 3, and (c) to (f) are boundary lines AA, BB, C-. It is sectional drawing which shows a mode that C and DD were grind | polished. It is FIG. (1) which shows the structure of the apparatus used for a grinding | polishing process. It is FIG. (2) which shows the structure of the apparatus used for a grinding | polishing process. (A) is sectional drawing which shows the dome formation process which forms resin in the objective surface of the objective lens 9, and forms the dome shape 21, (b) is the objective lens 9 which formed the light guide fiber 1 and the dome shape 21 in FIG. It is sectional drawing which shows the adhering process which adhere | attaches the mounted image fiber 7 to the exterior part 3, (c) is sectional drawing which shows a mode that it grind | polished to boundary line DD, (d) is boundary line D-. It is sectional drawing which shows the mode of the resin layer 51 when grind | polished to D, (e) is sectional drawing which shows a mode that the resin layer 51 was peeled from the objective surface 13, (f) shows the objective surface 13 It is sectional drawing which shows an appearance. It is a figure which shows the whole structure of a thin fiberscope. (A) is a figure which shows the grinding | polishing process of the conventional small diameter fiberscope, (b) is sectional drawing which shows the mode of the front-end | tip part after grinding | polishing, (c) exists in the objective surface with the bad site | part 110b. It is a figure which shows doing.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

[Example 1]
FIG. 1 is a diagram for explaining a method for forming an end of a thin fiberscope according to the first embodiment of the present invention.

  In FIG. 1, a light guide fiber 1 is composed of a plurality of image fibers, and an illumination light introduction port is provided at one end (not shown) to face a light source. The illumination light propagates and irradiates an object. The inner tube 5 has a hollow cylindrical shape having openings at both ends, has a length of about 1 mm to 100 mm, and an image fiber 7 can be inserted into the hollow inside.

  The exterior portion 3 is made of a hollow cylindrical metal having openings at both ends, and the light guide fiber 1 and the inner tube 5 can be inserted into the hollow inside. The image fiber 7 has an objective lens 9 fixed to the tip, and projects the target image by propagating the light collected by the objective lens 9 to the other end.

  As shown in FIG. 1A, the tip portion 11 shows the positions of the light guide fiber 1 and the inner tube 5 fixed inside the exterior portion 3, and the extra length portion 12 protrudes from the tip portion 11. The positions of the light guide fiber 1 and the inner tube 5 are shown.

  Here, with reference to FIG. 1, the edge part formation method of the thin fiberscope based on Example 1 of this invention is demonstrated.

  FIG. 1 (a) shows a fixing process for fixing the light guide fiber 1 and the inner tube 5 to the exterior part 3. First, an adhesive is applied to the distal ends of the light guide fiber 1 and the inner tube 5, and immediately after that, is inserted into the cylindrical exterior portion 3, until the light guide fiber 1, the inner tube 5 and the exterior portion 3 are fixed. put. As a result, as shown in FIG. 1A, the extra length portion 12 composed of the light guide fiber 1 and the inner tube 5 protrudes from the exterior portion 3.

  Next, in the polishing process, when the adhesive is dried, the extra length portion 12 composed of the light guide fiber 1 and the inner tube 5 is gradually polished using a polishing machine, and finally the extra length portion 12 is obtained. To the boundary line AA between the tip 11 and the tip 11. As a result, as shown in FIG. 1B, the extra length portion 12 is polished and the tip portion 11 remains.

  FIG. 1C shows that the objective lens 9 is attached to the tip of the image fiber 7. First, the front end portion of the image fiber 7 and the end surface of the objective lens 9 opposite to the objective surface are bonded or fusion-bonded. Or you may connect using a sleeve etc. As a result, the image fiber 7 to which the objective lens 9 shown in FIG.

  Next, FIG. 1D is a side cross-sectional view of the thin fiber scope. The image fiber 7 having the objective lens 9 shown in FIG. 1C is inserted and attached to the opening of the inner tube 5 shown in FIG. 1B obtained by the polishing process described above. As a result, the thin fiberscope shown in FIG. 1 (d) is obtained.

  The objective surface 13 of the objective lens 9 provided in the thin fiberscope manufactured through such a process is not polished as in the conventional process, as shown in FIG. There is no change and assembly workability can be improved.

  In this way, the inner tube 5 having a hollow cylindrical shape and the light guide fiber 1 are aligned in the longitudinal direction, the adhesive is applied for a predetermined length, and is inserted into and fixed to the exterior portion 3. The protruding end portions of the light guide fiber 1 and the inner tube 5 are polished at right angles to the longitudinal direction, and the image fiber 7 in which the objective lens is fusion-connected is inserted into the hollow of the inner tube 5 after polishing. The object surface 13 can be prevented from being polished, and the optical characteristics of the objective lens 9 can be prevented from deteriorating.

  In the polishing process, after inserting a dummy such as a fiber covering the opening hole of the inner tube 5 in advance, the polishing operation is performed and the dummy is removed after polishing, so that the polishing is performed from the opening hole of the inner tube 5 to be inserted. It is possible to prevent dust such as an agent and polishing waste from entering the scope, and to prevent the opening hole of the inner tube 5 from being deformed.

  Further, when the inner tube 5 to be inserted is made of a light-shielding material, unnecessary light from the light guide fiber 1 can be prevented from entering the objective lens 9 and the image fiber 7, and image deterioration can be prevented. it can.

  Further, when the inner tube 5 to be inserted is made of a material having elasticity, that is, polyimide, nylon, polyethylene, urethane, fluorine resin, etc. are suitable. The load applied to the fiber 7 can be reduced, and the reliability during use and the yield during manufacturing can be improved.

  In addition, when the inner tube 5 to be inserted is made of a material having rigidity such as metal, that is, in the range of 5 μm to 0.5 mm in thickness of stainless steel, brass, adjacent bronze, aluminum, etc., depending on the manufacturing conditions, the stress However, even when a bending force in a direction orthogonal to the longitudinal direction is applied, it is possible to give a strength that does not break against bending.

[Example 2]
FIG. 2 is a diagram for explaining a method of forming an end portion of a thin fiber scope according to the second embodiment of the present invention. 3 and 4 are views (Nos. 1 and 2) showing the configuration of the apparatus used in the polishing process.

  FIG. 2A shows a dome forming process for forming a dome shape 21 by depositing resin on the objective surface (end surface) of the objective lens 9 with respect to the objective lens 9 attached to the tip of the image fiber 7. .

  FIG. 2B shows a fixing process in which the light guide fiber 1 and the image fiber 7 to which the objective lens 9 having the dome shape 21 is attached are fixed to the exterior portion 3. First, an adhesive is applied to the ends of the light guide fiber 1 and the image fiber 7 and the dome shape 21, and immediately thereafter, the adhesive is inserted into the cylindrical exterior portion 3. It is left until the shape 21 and the exterior part 3 are fixed. As a result, as shown in FIG. 1B, the extra length portion 12 formed of the light guide fiber 1 and the tip of the image fiber 7 and the dome shape 21 protrudes from the exterior portion 3.

  Next, in the polishing process, when the adhesive is dried, the extra length portion 12 composed of the light guide fiber 1 and the tip of the image fiber 7 and the dome shape 21 is gradually polished using a polishing machine.

  Here, with reference to FIG. 3, the polishing step (part 1) will be described in detail.

  In FIG. 3, when the controller 45 outputs an ON command to the polishing machine 31, a motor (not shown) provided in the polishing machine 31 starts to rotate and rotates the polishing board 33. A polishing agent is applied to the polishing disk 33, and the tip of the small diameter fiber scope 37 is fixed by a jig 35 so as to be movable in the vertical direction of the paper surface. The tip of the scope 37 can be polished.

  The light emitted from the light source 41 passes through the half mirror 39 and enters one end of the small-diameter fiberscope 37, propagates through the light guide fiber 1, is reflected from the tip by the polishing board 33, and enters the image fiber 7. Then, it propagates through the image fiber 7, is emitted from one end to the half mirror 39, is reflected by the half mirror 39, and is incident on the detector 43.

  The detector 43 photoelectrically converts incident light to generate an electric signal and gives the electric signal to the controller 45. Therefore, the controller 45 is provided at the tip of the image fiber 7 when the electric signal exceeds the reference value. It is determined that the polishing process is proceeding very close to the objective surface 13 of the objective lens 9, and an OFF command is output to the polishing machine 31. As a result, a motor (not shown) provided in the polishing machine 31 stops rotating and the polishing disk 33 stops rotating.

  Next, with reference to FIG. 4, the polishing step (No. 2) will be described in detail.

  In FIG. 4, when the controller 45 outputs an ON command to the polishing machine 31, a motor (not shown) provided in the polishing machine 31 starts to rotate and rotates the polishing board 33. A polishing agent is applied to the polishing disk 33, and the tip of the small diameter fiber scope 37 is fixed by a jig 35 so as to be movable in the vertical direction of the paper surface. The tip of the scope 37 can be polished.

  The polishing board 33 is made of a transparent material, transmits light emitted from the light source 41, and enters the tip of the small diameter fiber scope 37.

  The light incident from the tip of the small diameter fiberscope 37 is propagated by the image fiber 7 and is incident on the detector 43 from the other end.

  The detector 43 photoelectrically converts incident light to generate an electric signal and gives the electric signal to the controller 45. Therefore, the controller 45 is provided at the tip of the image fiber 7 when the electric signal exceeds the reference value. It is determined that the polishing process is proceeding very close to the objective surface 13 of the objective lens 9, and an OFF command is output to the polishing machine 31. As a result, a motor (not shown) provided in the polishing machine 31 stops rotating and the polishing disk 33 stops rotating.

  Here, the progress of the polishing process will be described with reference to the cross-sectional views shown in FIGS.

  As shown in FIGS. 2C to 2F, the layer of the adhesive 23 appears so as to be surrounded by the light guide fiber 1 at the boundary line AA, and the boundary of the adhesive 23 appears at the boundary line BB. The resin layer 25 which becomes the cross section of the dome shape 21 appears a little in the layer, and the resin layer 25 which becomes the cross section of the dome shape 21 spreads and appears in the layer of the adhesive 23 at the boundary line CC. The boundary line DD shows that the resin layer 25 having a cross section of the dome shape 21 is polished and the polishing process is proceeding to a position very close to the objective surface 13 of the objective lens 9.

  As described above, when the polishing process proceeds to the boundary line DD, the magnitude of the electrical signal given from the detector 43 to the controller 45 exceeds the reference value, so that an OFF command is output from the controller 45 to the polishing machine 31. As a result, a motor (not shown) provided in the polishing machine 31 stops rotating and the polishing disk 33 stops rotating.

  As a result, it can be seen that the polishing process is proceeding to the vicinity of the objective surface of the objective lens 9, and therefore the objective surface of the objective lens 9 is not directly polished, so that the optical characteristics of the objective lens 9 are not adversely affected. It will be.

  In this way, a resin having a dome shape 21 is formed on the objective surface of the objective lens 9, and the image fiber 7 and the light guide fiber 1 having the objective lens 9 on which the dome-shaped resin is formed are aligned in the longitudinal direction. Adhesive is applied for a predetermined length from the tip, inserted into the exterior 3 and fixed, and the tip of the tip of the objective lens 9 from the objective surface 13 is longitudinally attached to the fixed image fiber 7 and light guide fiber 1. Since the resin layer adhering to the objective surface 13 of the objective lens 9 is peeled off after polishing, the objective surface of the objective lens 9 is prevented from being polished, and the optical characteristics of the objective lens 9 are deteriorated. Can be prevented.

  When the adhesive 23 is transparent or transmits light, it is preferable that the resin deposited on the objective surface (end surface) of the objective lens 9 is difficult to transmit light. Conversely, when the adhesive 23 is difficult to transmit light, it is preferable to use a resin that can easily transmit light as the resin used for forming the dome shape 21. When the adhesive 23 used for the tip is black, the resin used for forming the dome shape 21 may be a transparent type.

  Similarly, the resin used for forming the dome shape 21 may be colored by adding a dye or a pigment. For example, food red may be added to an acrylic UV curable resin, or the reflectance may be varied using a resin containing metal powder.

  In the above-described polishing step, the polishing end surface may be polished while inspecting with a microscope or the like. At this time, if the polishing surface of the dome shape 21 is used as an index, it becomes close to the objective surface 13 of the objective lens 9. Therefore, the degree of polishing can be adjusted and the objective surface 13 of the objective lens 9 can be hardly scraped, so that the optical characteristics of the objective lens 9 are not adversely affected.

Example 3
FIG. 5 is a diagram for explaining a method for forming an end of a thin fiberscope according to the third embodiment of the present invention.

  5A, as in FIG. 2A, with respect to the objective lens 9 attached to the tip of the image fiber 7, resin is deposited on the objective surface (end surface) of the objective lens 9 to form a dome shape 21. FIG. The dome formation process is shown. 5B shows a fixing process for fixing the light guide fiber 1 and the image fiber 7 on which the objective lens 9 having the dome shape 21 is mounted to the exterior portion 3 as in FIG. 2B. ing.

  FIG. 5C shows a side view of the small-diameter fiberscope when the polishing process proceeds to the boundary line DD and the rotation of the polishing plate 33 stops before the objective surface 13 of the objective lens 9. . FIG. 5D shows a cross-sectional view of the thin fiber scope when the polishing process proceeds to the boundary line DD and the rotation of the polishing board 33 stops. At this time, the surface of the object plane 13 is extremely exposed. It shows that the thin resin layer 51 remains without being polished.

  FIG. 5E is a side view of a thin fiber scope showing a state in which the extremely thin resin layer 51 is peeled off from the surface of the object surface 13 and the object surface 13 is visible from the outside. FIG. 5F is a cross-sectional view showing a state in which the extremely thin resin layer 51 is peeled off from the surface of the objective surface 13 and the objective surface 13 is visible from the outside.

  Thus, by using a resin made of an uncured material for forming the dome shape 21, the resin layer adhering to the objective surface 13 of the objective lens 9 can be peeled off after polishing, and the objective surface of the objective lens 9 can be peeled off. 13 can be prevented from being polished, and optical characteristics of the objective lens 9 can be prevented from deteriorating.

  It should be noted that the resin formed in the dome shape 21 has a strength lower than that of the adhesive used for the tip, and has a very small adhesive force, for example, a material that is soluble by solvent or heating. As this resin, for example, when an epoxy resin is bonded to the tip, an acrylic, urethane, or silicone resin that is softer than the epoxy resin may be used. Or you may use the resin which increased the amount of fillers to the existing resin.

  Further, as the resin formed in the dome shape 21, a resin such as urethane or silicone that does not firmly adhere to the objective surface 13 of the objective lens 9 may be used. Alternatively, a resin having a low adhesive strength or a resin that swells with a solvent or the like may be used.

  Further, the resin formed in the dome shape 21 can be removed by heating, a solvent or the like (not dissolving the adhesive used for the tip). For example, a resin that is weak against water or an organic solvent, paraffin, a slightly uncured resin, a resin with an increased amount of filler, or a resin in which a solvent such as xylene is added to silicone may be used.

  That is, the polishing process is stopped while the resin layer forming the dome shape 21 is left, and the objective surface 13 of the objective lens 9 is directly removed by wiping off the resin adhering to the objective surface 13 and removing the resin layer. Polishing can be avoided, and the optical characteristics of the objective lens 9 are not adversely affected.

DESCRIPTION OF SYMBOLS 1 Light guide fiber 3 Exterior part 5 Inner tube 7 Image fiber 9 Objective lens 11 Tip part 12 Extra length part 13 Objective surface 21 Dome shape 31 Polishing machine 33 Polishing board 35 Jig 37 Thin fiber scope 39 Half mirror 41 Light source 43 Detector 45 Controller 51 Resin layer

Claims (2)

The light guide fiber that propagates the irradiation light and irradiates the object and the image fiber that receives the reflected light from the object by the objective lens and propagates it into a hollow cylindrical shape provided in the small-sized exterior part A method of manufacturing a thin fiberscope to be inserted and fixed,
A fixing process in which an inner tube having a hollow cylindrical shape and the light guide fiber are aligned in the longitudinal direction, an adhesive is applied for a predetermined length, and inserted into an exterior portion to be fixed;
A polishing step of polishing the light guide fiber protruding from the exterior portion and the tip portion of the inner tube at right angles to the longitudinal direction;
And a step of inserting an image fiber in which an objective lens is fused and connected into the hollow of the inner tube after polishing. The polishing step includes
2. The opening hole provided in the distal end portion of the inner tube is polished after a longitudinal dummy member having an outer diameter smaller than that of the opening hole is inserted in advance, and the dummy member is removed after polishing. Method for manufacturing a thin fiberscope.