JP5271818B2 - Scanning optical fiber - Google Patents

Description

  The present invention relates to a scanning optical fiber used for a scanning fiber endoscope (SFE), and more particularly to an optical fiber fixing member.

  A scanning optical fiber is an illuminating device that is stored and used at a distal end portion of an endoscope scope, and includes an optical fiber that guides illumination light from an endoscope processor to a subject, and a driving member that drives the optical fiber. For example, it is mainly composed of a piezoelectric element, a lens for condensing illumination light on a subject, and a casing for storing them. A piezoelectric element is attached around the optical fiber, and the optical fiber and the piezoelectric element are fixed to a casing of the scanning optical fiber via a fixing member. A lens is provided so that it may adjoin to the front-end | tip of an optical fiber (patent document 1).

JP 2008-43763 A

  In order to accurately illuminate the subject with illumination light, it is necessary to match the central axis of the optical fiber with the optical axis of the lens. This operation is called optical axis alignment operation. In order to perform the optical axis alignment operation, the optical fiber is supported, the center axis of the optical fiber is aligned with the optical axis of the lens, and then the fixing member and the casing are fixed. However, since the optical fiber has low rigidity, the optical fiber cannot be reliably supported when the central axis and the optical axis are aligned, and the optical fiber is shaken, so that the optical axis alignment operation cannot be stably performed, that is, the center. There is a possibility that the axis and the optical axis cannot be reliably matched.

  Furthermore, in order to apply a voltage to the piezoelectric element, the conductive cable may be soldered to the piezoelectric element. In many cases, since the casing is made of a conductive material such as stainless steel, it is necessary to ensure insulation between the casing and the soldered portion. For this reason, the structure filled with resin between a casing and a soldering part can be considered. However, in this configuration, there is a possibility that sufficient insulation cannot be secured when bubbles or the like are mixed in the resin or insufficient filling occurs. If insulation cannot be secured sufficiently, there is a risk that the subject may be put in danger, and there is a risk that the various standards for ensuring the safety of the endoscope will not be met.

  The present invention has been made in view of these problems, and it is possible to easily and reliably match the center axis of the optical fiber with the optical axis of the lens, and to ensure insulation from the casing. An object of the present invention is to obtain a scanning optical fiber capable of satisfying the requirements.

  A scanning optical fiber according to the present invention is a scanning optical fiber used for an endoscope scope, and is inserted into a cylindrical driving member connected to a proximal end of a conductive cable and an inner surface of the driving member. And a fixing member having a cylindrical first cylindrical portion and a second cylindrical portion made of an insulating member, and the second cylindrical portion has a cross section perpendicular to the extending direction thereof. A second inner surface having a cross-sectional area larger than a cross-sectional area at a connection portion between the drive member and the conductive cable, and the first tube portion is located inside the inner surface of the second tube portion; A first inner side surface for gripping the proximal end side of the drive member so that the fixing member has a proximal end side end portion of the first cylindrical portion and a distal end side end portion of the second cylindrical portion; It is the shape which connected.

  It is preferable that the first tube portion and the second tube portion are cylindrical, and the first inner surface and the second inner surface are cylindrical.

  It is preferable that an adhesive filled between the proximal end portion of the driving member and the second inner surface is provided.

  The adhesive preferably has an insulating property.

  It is preferable that the outer diameter of the second cylindrical portion is larger than the outer diameter of the first cylindrical portion.

  The fixing member includes a cylindrical housing to which a lens is attached, and the outer periphery of the first cylindrical portion is engaged with the inner peripheral surface of the housing, and the optical fiber axis is aligned with the optical axis of the lens. It is preferably inserted into the inner periphery of the distal end portion of the endoscope.

  According to the present invention, it is possible to obtain a scanning optical fiber that can easily and surely perform the center axis of the optical fiber and the optical axis of the lens and that can reliably ensure insulation from the casing.

It is sectional drawing of a scanning optical fiber. It is a front view of a fixing member. It is a side view of a fixing member. It is a rear view of a fixing member. It is a perspective view of a fixing member. It is the figure which showed the scanning optical fiber when performing the optical axis alignment operation | work.

  Hereinafter, the scanning optical fiber 100 in the present invention will be described with reference to the accompanying drawings. First, the configuration of the scanning optical fiber 100 will be described with reference to FIGS.

  The scanning optical fiber 100 includes a cylindrical piezoelectric actuator 110 that is a driving member, a single mode optical fiber 120, an insulating member such as PEEK (polyether ether ketone) or ceramic, and a fixed member 130. A cylindrical casing 140 is mainly provided.

  The casing 140 is made of a metal such as stainless steel or titanium, and the outer peripheral surface 141 and the inner peripheral surface 142 form a circumferential surface. A casing 140 is stored on the inner periphery of the distal end portion of the endoscope scope (not shown), that is, the inner periphery of the tip portion closest to the observation object.

  A plurality of lenses 150 are attached to the distal end side end of the casing 140. The plurality of lenses 150 are fitted to the inner peripheral surface 142 of the casing 140 such that the optical axis coincides with the central axis X of the casing 140.

  A part of the fixing member 130 is fitted into the proximal end side end portion of the casing 140. As shown in FIGS. 3 and 5, the fixing member 130 has a shape in which two cylinders having different diameters are coaxially connected. A cylinder having a small outer diameter forms the first tube portion 131, and a cylinder having an outer diameter and an inner diameter larger than the first tube portion 131 forms the second tube portion 135. The outer surface 132 of the first cylindrical portion 131 engages with the inner peripheral surface 142 of the casing 140. Hereinafter, the outer surface 132 of the first cylindrical portion 131 is referred to as a first outer peripheral surface 132.

  The piezoelectric actuator 110 is fitted with the inner side surface 133 of the first cylindrical portion 131 and is fixed by an adhesive provided between the piezoelectric actuator 110 and the inner side surface 133. Hereinafter, the inner side surface 133 of the first cylindrical portion 131 is referred to as a first inner peripheral surface 133. The piezoelectric actuator 110 has a cylindrical shape, and the distal end side end portion has a conical shape. The piezoelectric actuator 110 protrudes in the axial direction from the end on the distal end side of the fixing member 130, but does not protrude from the end on the proximal end side of the fixing member 130.

  The distal end of the power cable 170 is soldered to the proximal end side end of the piezoelectric actuator 110. The proximal end of the power cable 170 extends to the proximal end of the endoscope scope and is connected to the endoscope processor to receive power.

  The single mode optical fiber 120 is fitted to the inner peripheral surface 111 of the piezoelectric actuator 110 and is fixed by an adhesive provided between the outer peripheral surface of the single mode optical fiber 120 and the inner peripheral surface 111 of the piezoelectric actuator 110. The single-mode optical fiber 120 is a flexible cylinder whose distal end is the distal end of the piezoelectric actuator 110 from the distal end of the piezoelectric actuator 110 to the vicinity of the rear lens of the plurality of lenses 150. Projects in the axial direction from the side end. The single mode optical fiber 120 is attached so that its axis coincides with the optical axes of the plurality of lenses 150. The proximal end of the single mode optical fiber 120 extends to the proximal end of the endoscope scope and is connected to an endoscope processor to receive illumination light.

  An adhesive 160 made of an insulating resin is filled between the proximal end side end of the piezoelectric actuator 110 and the inner side surface 137 of the second cylindrical portion 135. Thereby, the power cable 170 and the single mode optical fiber 120 extending from the proximal end side end portion of the piezoelectric actuator 110 are fixed to the fixing member 130, and insulation of the soldering portion 180 can be ensured. Hereinafter, the inner surface 137 of the second cylindrical portion 135 is referred to as a second inner peripheral surface 137.

  Next, the fixing member 130 will be described in detail.

  The first outer peripheral surface 132 has a slightly smaller diameter than the inner peripheral surface 142 of the casing 140, and the first inner peripheral surface 133 has a slightly larger diameter than the outer peripheral surface 112 of the piezoelectric actuator 110. The first outer peripheral surface 132 and the casing 140 are arranged so that the axis of the single-mode optical fiber 120 can coincide with the optical axes of the plurality of lenses 150, in other words, the optical axis alignment operation can be performed. Some play is provided between the inner peripheral surface 142.

  The second outer peripheral surface 136 that is the outer surface of the second cylindrical portion 135 has substantially the same diameter as the outer peripheral surface 141 of the casing 140. The second inner peripheral surface 137 has a cross-sectional area larger than the cross-sectional area of the soldering portion 180 by the piezoelectric actuator 110 and the power cable 170 in the extending direction, that is, in a cross section perpendicular to the axial direction. As a result, the second cylindrical portion 135 can cover the soldering portion 180 over the entire circumference. And since the 2nd cylinder part 135 is an insulator, it can prevent that the soldering part 180 contacts the casing 140 electrically.

  Next, the optical axis alignment operation will be described with reference to FIGS. A plurality of lenses 150 are attached to the casing 140. On the other hand, the power cable 170 and the single mode optical fiber 120 are fixed to the fixing member 130 with an adhesive 160. The attachment of the fixing member 130 and the casing 140 formed in this way will be described.

  In the optical axis alignment operation, an optical position sensor 210 that detects the position of irradiated light, an XYZ stage 220 that can move in three axial directions, and a controller 230 that is electrically connected to these are used. The XYZ stage 220 has a grip portion 221 for gripping the second outer peripheral surface 136. The controller 230 drives the XYZ stage 220 based on the position of light transmitted from the optical position sensor 210.

  First, the casing 140 is fixed with a jig (not shown) so that the optical axis of the lens 150 is perpendicular to a predetermined point on the position detection surface 211 of the optical position sensor 210. Then, the second outer peripheral surface 136 is held by the grip portion 221. Next, the first cylindrical portion 131 of the fixing member 130 to which the single mode optical fiber 120 and the piezoelectric actuator 110 are attached is inserted into the inner periphery of the casing 140. At this time, play is provided between the proximal end portion of the second cylindrical portion 135 and the distal end side end portion of the casing 140. That is, the fixing member 130 is inserted into the inner periphery of the casing 140 to a position where the second cylindrical portion 135 does not engage with the casing 140.

  Next, light is sent to the single mode optical fiber 120 and irradiated toward the lens 150. Light passing through the lens 150 is applied to the position detection surface 211. At this time, the control unit 230 drives the XYZ stage 220 to adjust the position of the fixing member 130 so that the light passing through the lens 150 is irradiated to a predetermined point on the position detection surface 211. As described above, since some play is provided between the first outer peripheral surface 132 and the inner peripheral surface 142 of the casing 140, the position of the fixing member 130 can be moved with respect to the casing 140. Thereby, the axis of the single mode optical fiber 120 coincides with the optical axis of the lens 150.

  Then, after the two axes coincide with each other, an insulating adhesive is poured into the gap between the first outer peripheral surface 132 of the fixing member 130 and the inner peripheral surface 142 of the casing 140 to fix the fixing member 130 and the casing 140 together. The optical scanning fiber 100 is obtained.

  According to this embodiment, the optical axis alignment operation can be performed stably, and a sufficient withstand voltage can be ensured even if bubbles or the like are mixed into the adhesive 160.

  Note that the first and second tube portions 131 and 135 may not be cylinders, and may be square tubes or the like.

  Further, the driving member is not limited to the piezoelectric actuator.

DESCRIPTION OF SYMBOLS 100 Scanning type optical fiber 110 Piezoelectric actuator 120 Single mode optical fiber 130 Fixing member 131 1st cylinder part 132 1st outer peripheral surface 133 1st inner peripheral surface 135 2nd cylindrical part 136 2nd outer peripheral surface 137 2nd Inner surface 140 casing 150 lens 160 adhesive 170 power cable 180 soldering part 210 optical position sensor 211 position detection surface 220 XYZ stage 221 gripping part 230 control part

Claims (6)

A scanning optical fiber used for an endoscope scope,
A cylindrical drive member with a conductive cable connected to the proximal end;
An optical fiber inserted into the inner surface of the drive member;
A fixing member having a cylindrical first cylindrical portion and a second cylindrical portion made of an insulating member;
The second cylindrical portion includes a second inner surface having a cross-sectional area larger than a cross-sectional area at a connection portion between the driving member and the conductive cable in a cross-section perpendicular to the extending direction.
The first tube portion includes a first inner surface that grips the proximal end side of the drive member so that the connection portion is positioned inside the inner surface of the second tube portion,
The scanning optical fiber, wherein the fixing member has a shape in which a proximal end side end portion of the first cylindrical portion is connected to a distal end side end portion of the second cylindrical portion.   2. The scanning optical fiber according to claim 1, wherein the first cylindrical portion and the second cylindrical portion are cylindrical, and the first inner surface and the second inner surface are cylindrical.   The scanning optical fiber according to claim 2, further comprising an adhesive filled between a proximal end portion of the driving member and the second inner surface.   The scanning optical fiber according to claim 3, wherein the adhesive has an insulating property.   The scanning optical fiber according to claim 1, wherein an outer diameter of the second cylindrical portion is larger than an outer diameter of the first cylindrical portion. A cylindrical housing with a lens attached,
The fixing member is arranged so that an outer periphery of the first tube portion is engaged with an inner peripheral surface of the housing, and an optical fiber axis is aligned with an optical axis of the lens. The scanning optical fiber according to claim 1, which is inserted into an inner periphery.

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