WO2017208402A1

WO2017208402A1 - Shape detection device

Info

Publication number: WO2017208402A1
Application number: PCT/JP2016/066266
Authority: WO
Inventors: 久保井　徹
Original assignee: オリンパス株式会社
Priority date: 2016-06-01
Filing date: 2016-06-01
Publication date: 2017-12-07
Also published as: JPWO2017208402A1

Abstract

Each of a plurality of shape detection sensors (10) has: a light source section (12) that outputs detection light; an optical fiber (14a) for shape detection, said optical fiber guiding the detection light outputted from the light source section; at least one section (22) to be detected, said section changing the characteristics of the detection light corresponding to the curvature of the optical fiber, and being provided in the optical fiber; and an optical detection section (16) that detects the detection light guided through the optical fiber. At least a part of each optical fiber is disposed in an exterior cylindrical member (58), and a flexible resin (68) is applied between each optical fiber and at least an exterior cylindrical member part in the longitudinal axis direction (O₁) of the exterior cylindrical member. A sliding section is, for instance, an interface (72a) where the inner wall of the exterior cylindrical member, and the outer surface of the flexible resin are adjacent to each other, said sliding section making it possible to independently slide each optical fiber in the longitudinal axis direction (O₂) of the optical fiber.

Description

Shape detection device

The present invention relates to a shape detection device for detecting a curved shape, comprising a plurality of optical fibers for detection light having at least one detected portion.

In a cylindrical flexible device provided with a cylindrical flexible body, for example, an endoscope device provided with a flexible insertion portion to be inserted into a subject, a curved shape of the insertion portion is formed by incorporating a shape detection sensor. It is known to detect. The shape detection sensor has a light source unit that emits detection light, a detection light optical fiber that guides the detection light emitted from the light source unit, and a detection light characteristic according to the curvature of the detection light optical fiber. It has at least one detected part provided in the optical fiber for detection light that gives a change, and a light detection part that detects the detection light guided through the optical fiber for detection light. The detected portions are formed by, for example, light loss portions that lose light of different wavelengths, and are respectively disposed in predetermined directions at predetermined positions of the optical fiber for detection light. The amount of light transmitted through the optical fiber for detection light varies depending on the curvature and direction of the curvature of each detected portion. Based on the light transmission amount for each wavelength of the optical fiber for detection light, the curved shape of the insertion portion, that is, the curvature and direction of the curvature, in the portion where each detected portion is located is obtained.

When a large number of detection target parts are required, for example, as disclosed in Japanese Patent Application Laid-Open No. 2007-143600, a fiber in which the number of optical fibers for detection light is increased and the optical fibers for detection light are bundled A bundle is used.

JP 2007-143600 A

The shape detection sensor disclosed in Patent Document 1 has a structure in which a plurality of optical fibers for detection light are bonded and bundled in a sheath.

In order to bend a fiber bundle in which a plurality of optical fibers for detection light are bent in this way, the optical fiber for detection light arranged on the outside of the bend needs to be stretched, and the detection arranged on the inside of the bend The optical fiber for light needs to be shrunk. Therefore, it is preferable to use a material that can be expanded and contracted as the material of each optical fiber for detection light. However, many common optical fibers are difficult to expand and contract because the core or clad is made of quartz glass.

Therefore, in the fiber bundle as disclosed in Patent Document 1, when an optical fiber that is hard to expand and contract whose core or clad is quartz glass is used for each optical fiber for detection light, the fiber bundle cannot be expanded and contracted. There is a possibility that it cannot bend with the same curvature as the endoscope. Alternatively, the reliability of the shape detection sensor may be lowered, for example, by bending it to cause bending stress to break the optical fiber for detection light.

An object of the present invention is to provide a shape detection device whose reliability is not easily lowered even when a plurality of optical fibers for detection light are used.

A shape detection device according to an aspect of the present invention includes a light source unit that emits detection light, an optical fiber for shape detection that guides detection light emitted from the light source unit, and a detection light according to the curvature of the optical fiber. A plurality of shape detection sensors each having at least one detected portion provided in the optical fiber that changes characteristics, and a light detecting portion that detects detection light guided through the optical fiber; A shape calculating device that calculates a curved shape of the detected portion based on a change in characteristics of detection light detected by a plurality of light detection units of the plurality of shape detection sensors, and a plurality of the plurality of shape detection sensors An exterior cylindrical member in which at least a part of each of the optical fibers is installed; and at least a part of the exterior cylindrical member in the longitudinal axis direction of the exterior cylindrical member and the plurality of optical fibers; Comprises a filled flexible resin, and a sliding portion which can slide said plurality of optical fibers in the longitudinal direction of the independently on the optical fiber between.

According to the present invention, there is provided a shape detection device in which reliability is not easily lowered even when a plurality of optical fibers for detection light are used.

FIG. 1 is a schematic diagram for explaining the principle of a shape detection sensor incorporated in the shape detection apparatus according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view in the radial direction of the optical fiber for detection light of the shape detection sensor. FIG. 3 is a schematic diagram illustrating a configuration of an endoscope apparatus in which a shape detection sensor is incorporated. FIG. 4 is a schematic diagram for explaining a form of incorporation of the shape detection device probe included in the shape detection device according to the first embodiment into the endoscope apparatus insertion portion. FIG. 5 is an external perspective view of the shape detection device probe according to the first embodiment. FIG. 6 is a cross-sectional view in the longitudinal direction for explaining the configuration for incorporating the optical fiber for detection light into the shape detection apparatus probe in the first embodiment. FIG. 7A is a schematic diagram for explaining an example of a rigidity reinforcing member in the outer cylindrical member of the shape detection device probe. FIG. 7B is a schematic diagram for explaining another example of the rigidity reinforcing member in the outer tubular member of the shape detection device probe. FIG. 8 is a schematic diagram for explaining the action of the flexible resin in the shape detection apparatus probe according to the first embodiment. FIG. 9 is an external perspective view of the shape detection device probe in the shape detection device according to the second embodiment of the present invention. FIG. 10 is a cross-sectional view in the longitudinal direction for explaining the configuration for incorporating the optical fiber for detection light into the shape detection apparatus probe in the second embodiment. FIG. 11 is a longitudinal cross-sectional view for explaining a configuration in which the optical fiber for detection light is incorporated into the shape detection device probe in the shape detection device according to the third embodiment of the present invention. FIG. 12 is a longitudinal cross-sectional view for explaining a configuration in which the optical fiber for detection light is incorporated into the shape detection device probe in the shape detection device according to the fourth embodiment of the present invention.

[First Embodiment]
The shape detection apparatus according to the first embodiment of the present invention incorporates a plurality of shape detection sensors. First, the configuration and operation of the shape detection sensor will be described.

FIG. 1 is a schematic diagram for explaining the principle of the shape detection sensor 10. The shape detection sensor 10 includes a light source unit 12, an optical fiber 14, and a light detection unit 16. The optical fiber 14 is connected to the light source unit 12 and the light detection unit 16. The light source unit 12 is, for example, an LED light source or a laser light source, and emits detection light having a desired wavelength characteristic. The optical fiber 14 is an optical fiber for measuring a curved shape that propagates detection light emitted from the light source unit 12. The light detection unit 16 detects the detection light propagated through the optical fiber 14.

The optical fiber 14 includes a detection light optical fiber 14 a, a light supply optical fiber 14 b, and a light receiving optical fiber 14 c that are branched in three directions by a coupling portion (optical coupler) 18. That is, the optical fiber 14 is formed by connecting the light supply optical fiber 14 b and the light receiving optical fiber 14 c to the detection light optical fiber 14 a by the coupling portion 18. The proximal end of the light supply optical fiber 14 b is connected to the light source unit 12. In addition, a reflection portion 20 that reflects the propagated light is provided at the tip of the detection light optical fiber 14a. The reflection unit 20 is, for example, a mirror. The proximal end of the light receiving optical fiber 14 c is connected to the light detection unit 16.

The light supply optical fiber 14 b propagates the detection light emitted from the light source unit 12 and guides it to the coupling unit 18. The coupling unit 18 directs most of the detection light incident from the light supply optical fiber 14b to the detection light optical fiber 14a. The detection light optical fiber 14 a guides the detection light from the coupling unit 18 to the reflection unit 20, and guides the detection light reflected by the reflection unit 20 to the coupling unit 18. The coupling unit 18 directs at least a part of the detection light from the detection light optical fiber 14a to the light reception optical fiber 14c. The light receiving optical fiber 14 c guides the light from the coupling unit 18 to the light detection unit 16. The light detection unit 16 photoelectrically converts the detection light received from the light receiving optical fiber 14c and outputs an electric signal indicating the amount of received light.

The optical fiber 14a for detection light has at least one detected part 22. FIG. 2 is a radial cross-sectional view of the detection light optical fiber 14a at the detected portion 22 position.

The optical fiber for detection light 14 a has a core 24, a clad 26 covering the outer peripheral surface of the core 24, and a coating 28 covering the outer peripheral surface of the clad 26. The core 24 and the clad 26 are made of quartz glass having different refractive indexes. At least one detected portion 22 is provided on the side surface of the detection light optical fiber 14a. The detected portion 22 is provided only at a part of the outer periphery of the detection light optical fiber 14a, and the characteristics of the detection light passing through the detected portion 22 are changed in the curved shape of the detection light optical fiber 14a, that is, the curvature and direction of the curve. It changes according to.

The detected portion 22 has a light opening 30 from which the core 24 is exposed by removing a part of the coating 28 and the clad 26, and a light characteristic conversion member 32 formed in the light opening 30. . The core 24 does not necessarily have to be exposed as the light opening 30, and the core 24 may not be exposed as long as the light passing through the detection light optical fiber 14 a reaches the light opening 30. The light characteristic conversion member 32 is a member that converts the characteristics (light quantity, wavelength, etc.) of the light guided through the detection light optical fiber 14a. For example, a light guide loss member (light absorber) or a wavelength conversion member ( Phosphor). In the following description, it is assumed that the light characteristic conversion member is a light guide loss member.

In the shape detection sensor 10, the light supplied from the light source unit 12 guides the detection light optical fiber 14a as described above. When the detection light propagating through the detection light optical fiber 14 a enters the light characteristic conversion member 32 of the detected portion 22, a part of the detection light is absorbed by the light characteristic conversion member 32. For this reason, a loss of detection light guided by the detection light optical fiber 14a occurs. The light guide loss amount varies depending on the bending amount of the detection light optical fiber 14a.

For example, even if the optical fiber 14a for detection light is in a straight line state, a certain amount of detection light is lost by the optical characteristic conversion member 32 according to the width, length, etc. of the light aperture 30. If the optical characteristic conversion member 32 is arranged outside the relatively large curvature radius in the curved state of the optical fiber for detection light 14a based on the light loss amount in the straight line state, the light guide loss amount as a reference More light guide loss occurs. In addition, if the optical property conversion member 32 is disposed on the inner side having a relatively small radius of curvature in the curved state of the detection light optical fiber 14a, a light guide loss amount smaller than the reference light guide loss amount is generated.

The change in the light guide loss amount is reflected in the detected light amount received by the light detection unit 16, that is, the output signal of the light detection unit 16. Therefore, based on the output signal of the light detection unit 16, the curved shape of the detection light optical fiber 14 a at the position of the detected part 22 of the shape detection sensor 10, that is, the position where the optical characteristic conversion member 32 is provided. Is possible.

In FIGS. 1 and 2, only one detected portion 22 is shown, but a plurality of detected portions 22 are arranged on the axis of the detection light optical fiber 14a. It may be provided at intervals along. As a result, it is possible to detect bending at a plurality of positions along the axis of the optical fiber for detection light 14a. Alternatively, the two detection target portions 22 may be provided at substantially the same position along the axis of the single detection light optical fiber 14a and at different positions along the circumference (for example, positions orthogonal to each other). This makes it possible to obtain not only a curve in one direction but also a curve in two directions orthogonal to each other. When a plurality of detected portions 22 are provided in one detection light optical fiber 14a, for example, the plurality of detected portions 22 change the characteristics of light having different wavelengths, and the light source portion 12 includes the detected portions. The detection light including a plurality of wavelength components corresponding to 22 is emitted or the detection light subjected to wavelength sweeping is emitted, and the light detection unit 16 detects the detection light for each wavelength component corresponding to the detected portion 22. Configured.

Next, the configuration of the endoscope apparatus in which the shape detection apparatus according to the first embodiment is incorporated will be described. FIG. 3 is a diagram schematically showing the endoscope apparatus 34.

The endoscope apparatus 34 includes a scope portion 36 in which at least the detection light optical fiber 14 a of the shape detection sensor 10 is incorporated, and a main body portion 38. The main body 38 includes a control device 40, a shape calculation device 42, a video processor 44, and a display device 46.

The control device 40 controls predetermined functions of the peripheral device connected to the scope unit 36, the shape calculation device 42, the video processor 44 and the like.

The scope section 36 includes an insertion section 48 that is a cylindrical flexible body that is inserted into the subject, and an operation section 50 that is provided on the proximal end side of the insertion section 48. A cord portion 52 extends from the operation portion 50. The scope section 36 is detachably connected to the main body section 38 via the cord section 52 and communicates with the main body section 38. The operation unit 50 is provided with an operation dial 54 for inputting an operation for bending the bending portion 48a of the insertion portion 48 in at least two specific directions (for example, the vertical direction) with a desired curvature. The cord portion 52 houses a light guide fiber 62a, a camera cable 64c, and the like which will be described later.

In addition, a channel tube, which is a cylindrical tube for passing a treatment instrument such as an ultrasonic probe or forceps, is disposed in the insertion portion 48 from the distal end portion to the proximal end side. Is provided with an opening 56 of the channel tube.

Note that the shape detection sensor 10 is not shown in FIG. 3, but the endoscope apparatus 34 includes the shape detection sensor 10 shown in FIG.

Specifically, the optical fiber 14a for detection light of the shape detection sensor 10 is mounted along a long cylindrical flexible body that is an object to be detected, which is the insertion portion 48 in the present embodiment. When mounting, the detected portion 22 of the detection light optical fiber 14 a is aligned with the desired detection position of the insertion portion 48, and the detection light optical fiber 14 a is mounted at an appropriate position of the insertion portion 48. . The optical fiber 14a for detection light is bent following the bending operation of the bending portion 48a of the insertion portion 48. The detection light detected by the light detection unit 16 through the detection unit 22 changes in characteristics, for example, the amount of light according to the change in the curvature of the detection light optical fiber 14 a in the peripheral portion of the detection unit 22. The light detection unit 16 outputs a received light amount signal. The output signal of the light detection unit 16 includes information on the curvature of the detected portion 22.

The shape calculation device 42 is connected to the light detection unit 16. The shape calculation device 42 receives the output signal from the light detection unit 16 and calculates the curved shape of the detected portion 22 based on this output signal. There is a correlation between the curved shape of the detected portion 22 and the curved shape of the curved portion 48a of the insertion portion 48 at the position where the detected portion 22 is disposed. Therefore, the shape calculating device 42 calculates the curved shape of the bending portion 48a of the insertion portion 48 at the position where the detected portion 22 is arranged based on the calculated curved shape of the detected portion 22. In other words, the shape calculation device 42 calculates the curved shape of the bending portion 48 a of the insertion portion 48 based on the change in the characteristics of the detection light detected by the light detection portion 16. The calculated curved shape is transmitted from the shape calculation device 42 to the display device 46 and displayed on the display device 46.

The video processor 44 performs image processing on the electrical signal acquired from the imaging device at the tip of the scope unit via the camera cable and the control device 40. The display device 46 displays the image in the subject processed by the video processor 44.

Details of the shape detection apparatus according to the first embodiment will be described below.
As shown in FIG. 4, the probe 1 of the shape detection device according to the first embodiment is mounted along the insertion portion 48 in the insertion portion 48 that is the object to be detected. In this probe 1, a plurality of optical fibers for detection light 14 a by a plurality of shape detection sensors 10 are collected and accommodated in an outer cylindrical member 58. A rigid insertion portion distal end member 48 b is provided at the distal end portion of the insertion portion 48, and a proximal end of the insertion portion 48 is a rigid insertion portion rear end member 48 c connected to the operation portion 50. The outer tubular member 58 of the probe 1 is disposed at least between the insertion portion front end member 48b and the insertion portion rear end member 48c. The outer tubular member 58 of the probe 1 is held and fixed to the insertion portion distal end member 48b or the insertion portion rear end member 48c. In the example of FIG. 4, the exterior cylindrical member 58 is fixed to the insertion portion distal end member 48 b by a distal end fixing portion 60 such as an adhesive. The tip fixing portion 60 may be an epoxy adhesive that can be expected to have high adhesive strength. The plurality of detection light optical fibers 14 a are accommodated in the cord portion 52 without the outer cylindrical member 58. That is, only a part of the plurality of optical fibers for detection light 14 a in the longitudinal axis direction is accommodated in the exterior cylindrical member 58.

The insertion portion 48 further includes a light guide fiber 62a, an illumination portion 62b, an imaging optical system 64a, an imaging element 64b, a camera cable 64c, a channel tube 56a, and an operation wire (not shown). . The light guide fiber 62a is connected to an illumination unit 62b disposed in the insertion unit distal end member 48b and a light source (not shown) in the control device 40, and guides illumination light from the light source to the illumination unit 62b. It is a member. The camera cable 64c is connected to the imaging device 64b and the control device 40 disposed in the insertion portion distal end member 48b, and is an electrical wiring that transmits an electrical signal. The channel tube 56a is a cylindrical tube for passing a treatment instrument such as an ultrasonic probe or forceps.

An operation wire (not shown) is provided along the axis in the insertion portion 48 in order to perform an operation of bending the bending portion 48a of the insertion portion 48 in a desired direction with a desired curvature, and an operation dial 54 of the operation portion 50 is provided. This operation is transmitted to the bending portion 48a. When the operator operates the operation dial 54 to move the operation wire, the bending portion 48a of the insertion portion 48 is bent.

As shown in FIGS. 5 and 6, the probe 1 of the shape detection device according to the first embodiment includes a plurality of, four in the present embodiment, penetrating the exterior cylindrical member 58 along the probe longitudinal axis O ₁ . It has a lumen 66. Each lumen 66 has an inner diameter slightly larger than the outer diameter of the detection light optical fiber 14a so that the single detection light optical fiber 14a can be inserted. The optical fiber for detection light 14a inserted into the lumen 66 and having the reflecting portion 20 attached to the tip thereof is held by the full length of the inserted optical fiber 14a via the flexible resin 68 filled in the lumen 66. Yes. The flexible resin 68 filled in the lumen 66 can be bent with a desired curvature.

The exterior cylindrical member 58 is formed of a resin such as a flexible fluororesin tube such as PTFE, a polyamide tube, or a PEEK tube.

The inner wall of the outer tubular member 58, that is, the inner wall of the lumen 66 and the flexible resin 68 are held and fixed by bonding at the fixing portion 70 at the tip of the probe 1. When the exterior cylindrical member 58 is made of a fluororesin such as PTFE, the adhesiveness is not good. In such a case, it is desirable that the exterior cylindrical member 58, that is, the inner wall of the lumen 66, be subjected to a surface treatment that improves adhesion, such as Na etching or plasma treatment.

Moreover, for example, PA (polyamide), ETFE or the like is used for the coating 28 of the optical fiber 14a for detection light. When the coating 28 is formed of a fluororesin such as ETFE, the surface is subjected to a surface treatment that improves adhesion such as Na etching or plasma treatment, so that the flexible resin 68 is applied. And the coating 28 can be firmly bonded. That is, the flexible resin 68 and the coating 28 do not slide in the optical fiber longitudinal axis O ₂ direction.

With respect to the interface 72a where the inner wall of the outer tubular member 58 and the outer surface of the flexible resin 68 are in contact with each other, except for a part of the tip of the probe 1 held and fixed by the fixing portion 70, the outer cylinder. The surface treatment for improving the adhesiveness between the inner wall of the cylindrical member 58, that is, the inner wall of the lumen 66 is not performed, and at the interface 72a in the portion where the surface treatment is not performed, 68 and is in slidable in the direction of the optical fiber longitudinal axis O ₂ to each other. That is, in the surface 72a, a flexible resin 68 is in slidable in the direction of the optical fiber longitudinal axis O ₂ relative to the outer tubular member 58 (lumen 66). Here, since the flexible resin 68 and the coating 28 of the optical fiber for detection light 14a are firmly joined, the sliding of the flexible resin 68 with respect to the exterior cylindrical member 58 (lumen 66) is the exterior. This means sliding of the optical fiber 14a for detection light with respect to the tubular member 58 (lumen 66). Therefore, a part of the interface 72a where the inner wall of the outer tubular member 58 (lumen 66) and the outer surface of the flexible resin 68 are adjacent is fixed within a desired range, and the probe length of the other outer tubular member 58 is fixed. axis interface 72a in the entire length direction of the O ₁ functions as a sliding portion for slidable detection-light optical fiber 14a with respect to the outer tubular member 58 to the optical fiber longitudinal axis O ₂ direction.

In FIG. 6, for convenience of illustration, the interface 72 a between the inner wall of the outer tubular member 58 (lumen 66) and the flexible resin 68 is shown with a thickness, but this has two layers. It is a contact part, Comprising: It does not have substantial thickness. In addition, the fixing portion 70 between the inner wall of the outer tubular member 58 (lumen 66) and the flexible resin 68 is also shown with a thickness, but in practice it is very thick such as 50 to 200 μm. A thin layer of adhesive.

The cross-sectional shape of the lumen 66 is not limited to a circle, and may be an ellipse, a triangle, a quadrangle, a polygon, or the like.

Further, the lumen 66 is not limited to the through-hole, and may be a multi-lumen tube molded integrally with the outer cylindrical member 58 (or the same material), or the outer cylindrical member 58 May have a structure in which a single tube molded separately is bundled with an outer cylindrical member 58. However, it is desirable that at least the inner wall of the lumen 66 is made of a fluororesin that does not have good adhesion, such as PTFE (poor wettability and good slidability).

Further, in the first embodiment, the detection light optical fiber 14a is held and fixed to the distal end portion of the outer tubular member 58 by the fixing portion 70. However, if only one place is fixed and held, The outer cylindrical member 58 may be a rear end portion or an intermediate portion.

Also, the number of optical fibers for detection light 14a is not limited to four, and may be at least two.

Note that, as shown in FIG. 7A, a rigid reinforcing member 58a such as a braid (blade) capable of reducing buckling and twisting of the outer tubular member 58 is embedded in the outer peripheral portion of the outer tubular member 58. Further, the rigidity reinforcing member 58a is not limited to such a mesh-structured blade, and may be a coil as shown in FIG. 7B, for example.

In addition, although not particularly illustrated, the shape detection apparatus includes at least one light source unit 12 and / or light detection unit 16 of at least one shape detection sensor 10 among the plurality of shape detection sensors 10 included in the shape detection device. The light source unit 12 and / or the light detection unit 16 of one shape detection sensor 10 may also be used. That is, a configuration in which the detection light emitted from one light source unit 12 is incident on the detection light optical fibers 14a of the plurality of shape detection sensors 10 and guided, or the detection light optical fibers of the plurality of shape detection sensors 10 are guided. It is possible to adopt a configuration in which the detection light whose characteristics are changed according to the curvature from 14a is incident on one light detection unit 16 and detected. That is, the shape detection device only needs to include at least one light source unit 12, a plurality of detection light optical fibers 14a, and at least one light detection unit 16.

In the probe 1 of the shape detecting device having the above-described configuration, as shown in FIG. 8, when bending, a tensile bending stress is generated in the lumen 66 disposed outside the bending, and the bending center ( It extends according to the amount of offset from the center of the outer cylindrical member 58). However, the surface 72a is sliding portion, since the flexible resin 68 is made slidable relative to the outer tubular member 58 to the optical fiber longitudinal axis O ₂ direction, significant for flexible resin 68 The force is not applied, and the flexible resin 68 is retracted into the outer tubular member 58, and the outer tubular member 58 and the detection light optical fiber 14a firmly bonded thereto can be bent.

Further, a compressive bending stress is generated in the lumen 66 arranged inside the bending, and the lumen 66 is shortened according to the offset amount from the bending center. However, the interface 72a is sliding portion, since the flexible resin 68 is in slidable relative outer tubular member 58 to the optical fiber longitudinal axis O ₂ direction, significant for flexible resin 68 The force is not applied, and the flexible resin 68 jumps out of the outer cylindrical member 58, and the outer cylindrical member 58 and the detection light optical fiber 14a firmly bonded thereto can be bent. .

The detection Hikari Mitsumochi fiber 14a is the entire outer periphery (over 360 ° full length) because it is covered with a flexible resin 68, twisted around the optical fiber longitudinal axis O ₂ is flexible resin The detection light optical fiber 14a is hardly twisted.

As described above, the shape detection device according to the first embodiment is a light source unit 12 that emits detection light, and a detection light optical fiber that is a shape detection optical fiber that guides detection light emitted from the light source unit 12. Through the optical fiber 14a, at least one detected portion 22 provided in the detection light optical fiber 14a that changes the characteristics of the detection light according to the curvature of the detection light optical fiber 14a, and the detection light optical fiber 14a A plurality of shape detection sensors 10 each having a light detection unit 16 for detecting the guided detection light, and characteristics of detection light detected by the plurality of light detection units 16 of the plurality of shape detection sensors 10 At least a part of each of the plurality of detection light optical fibers 14a of the plurality of shape detection sensors 10 and the shape calculation device 42 that calculates the curved shape of the detected portion 22 based on the change An exterior tubular member 58 to be installed, in the direction of the probe longitudinal axis O ₁ is a longitudinal axis of the outer tubular member 58 at least part of the exterior tubular member 58 and a plurality of detection-light optical fiber 14a a flexible resin 68 filled between a slidable plurality of detection-light optical fiber 14a to the direction of the optical fiber longitudinal axis O ₂ is the longitudinal axis of the independently to the detection-light optical fiber 14a And a sliding portion.
Therefore, even when the detection light optical fiber 14a is not stretchable and is offset from the center of bending, the detection light optical fiber 14a can be bent without impairing reliability. It is possible to provide a shape detection device that does not have a possibility of lowering reliability even if it is used.

In the first embodiment, the sliding portion is an interface 72 a where the inner wall of the exterior cylindrical member 58 and the outer surface of the flexible resin 68 are adjacent to each other.
In this case, a part of the interface 72a where the inner wall of the outer cylindrical member 58 and the outer surface of the flexible resin 68 are adjacent is fixed within a desired range, and the probe longitudinal axis O of the other outer cylindrical member 58 is fixed. _The interface 72a is a sliding part over the entire length in the direction of ₁ .
Therefore, the sliding of the detected portion 22 in the direction of the optical fiber longitudinal axis O ₂ exceeding the proper range can be restricted.

The inner wall of the outer tubular member 58 is an inner wall of a plurality of lumens 66 provided on the outer tubular member 58, and one of the plurality of optical fibers for detection light 14a is disposed in each of the plurality of lumens 66. The flexible resin 68 is filled in each of the plurality of lumens 66.
Therefore, each of the plurality of optical fibers for detection light 14a can be independently slid.

Here, the inner walls of the plurality of lumens 66 are formed of a fluororesin (for example, PTFE) that can reduce the sliding resistance of the interface 72a between the inner walls of the plurality of lumens 66 and the flexible resin 68.
Therefore, the sliding of the interface 72a can be made easier.

In addition, the outer surface of each of the plurality of optical fibers for detection light 14 a is subjected to surface modification that improves adhesion to the flexible resin 68.
Therefore, the detection optical fiber 14a can be reliably slid following the sliding of the interface 72a.

The shape detection apparatus according to the first embodiment further includes a rigidity reinforcing member 58a that can reduce buckling or twisting of the exterior cylindrical member 58.
Thereby, more accurate shape detection becomes possible.

Here, the rigidity reinforcing member 58a is a braid in which a wire is knitted.
Alternatively, the rigidity reinforcing member 58a is a coil in which a wire is formed in a spiral shape.

At least one of the plurality of shape detection sensors 10 may share the light source unit 12 and / or the light detection unit 16 with at least one other of the plurality of shape detection sensors 10.
Thereby, the number of parts can be reduced and an inexpensive apparatus can be provided.

Each of the plurality of optical fibers for detection light 14a is disposed along the longitudinal axis direction of the insertion portion 48 of the endoscope device 34, and the shape calculating device 42 is based on the calculated curved shape of each detected portion 22. Thus, the curved shape of the insertion portion 48 is calculated.
Therefore, it is possible to know the curved shape of the insertion portion 48 by incorporating the shape detection device according to the first embodiment into the endoscope.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. Below, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted, and only the parts different from the first embodiment will be described.

As shown in FIGS. 9 and 10, in the probe 1 of the shape detection apparatus according to the second embodiment, the outer cylindrical member 58 has a tube shape having an inner diameter capable of incorporating at least a plurality of optical fibers for detection light 14a. I am doing. Then, a plurality, four in the present embodiment, of the tube-shaped exterior cylindrical member 58 are inserted with the detection-light optical fibers 14a with the reflecting portions 20 attached to their tips, and the detection-light optical fibers 14a. Is held via a flexible resin 68 filled in the hollow portion of the tube.

Here, the inner wall of the exterior cylindrical member 58 is fixed and held by bonding with the flexible resin 68. When the exterior cylindrical member 58 is formed of a fluororesin or the like having a low bondability such as PTFE, the inner wall is subjected to a surface treatment for improving the adhesiveness such as an Na etching process, so that the flexible resin 68 and It is desirable to have a structure in which the outer cylindrical member 58 is firmly bonded and held.

On the other hand, the coating 28 of the detection light optical fiber 14a and the flexible resin 68 are held and fixed by bonding at a fixing portion 70 at the tip of the probe 1. The coating 28 is made of, for example, a fluorine resin such as ETFE or the like, and has poor adhesion. Therefore, it is desirable that the outer surface of the coating 28 at a position corresponding to the fixing portion 70 is subjected to a surface treatment that improves adhesion, such as Na etching or plasma treatment. For the portion that has not been subjected to such surface treatment, the bondability between the coating 28 and the flexible resin 68 remains low. Therefore, in the second embodiment, at the interface 72b that is the contact surface between the coating 28 and the flexible resin 68, the coating 28 can slide in the direction of the optical fiber longitudinal axis O ₂ with respect to the flexible resin 68. It has become. In this manner, a part of the interface 72b where the outer surface of the coating 28 of the optical fiber for detection light 14a and the inner surface of the flexible resin 68 are adjacent is fixed within a desired range, and the other outer cylindrical member 58 is fixed. interface 72b in the entire length direction of the probe longitudinal axis O ₁ functions as a sliding part to be slidable in the optical fiber longitudinal axis O ₂ direction detection-light optical fiber 14a with respect to the outer tubular member 58.

In FIG. 10, for convenience of illustration, the interface 72b between the coating 28 and the flexible resin 68 is shown with a thickness, but this is a contact portion between two layers, There is no thickness. Also, the fixing portion 70 between the coating 28 and the flexible resin 68 is shown with a thickness, but it is actually a very thin layer of adhesive such as a thickness of 50 to 200 μm.

Also in the probe 1 of the shape detection apparatus according to the second embodiment having the above-described configuration, the interface 72b that is the contact surface between the flexible resin 68 and the coating 28 is two in the same manner as the interface 72a in the first embodiment. Since the two layers are slidable with respect to each other, the outer tubular member 58 can be curved with a desired curvature even if the optical fiber for detection light 14a cannot be expanded and contracted.

As described above, in the shape detection device according to the second embodiment, the sliding portion is the interface 72b where the flexible resin 68 and each of the plurality of optical fibers for detection light 14a are adjacent to each other.
In this case, a part of the interface 72b where the flexible resin 68 and each of the plurality of optical fibers for detection light 14a are adjacent is fixed within a desired range, and the length of the other exterior cylindrical member 58 in the longitudinal axis direction is fixed. The interface 72b is a sliding part.
Accordingly, the sliding of the detected portion 22 in the direction of the optical fiber longitudinal axis O ₂ exceeding the proper range can be restricted, and the sliding of each of the plurality of optical fibers for detection light 14a can be independently performed. Can be done.
Furthermore, in the shape detection device according to the second embodiment, compared with the first embodiment, since the resistance when filling the exterior cylindrical member 58 with the flexible resin 68 is small, the filling speed can be increased. Therefore, it is possible to provide a cheaper shape detection device.

Here, the surface of the coating 28 which is the outer surface of each of the plurality of optical fibers for detection light 14a is the sliding resistance of the interface 72b between the outer surface of each of the plurality of optical fibers for detection light 14a and the flexible resin 68. It is formed of a fluororesin (for example, ETFE) that can reduce the above.
Therefore, the sliding of the interface 72a can be made easier.

In addition, the surface of the inner wall of the exterior tubular member 58 is subjected to surface modification that improves the adhesion to the flexible resin 68.
Therefore, sliding at the interface between the outer tubular member 58 and the flexible resin 68 can be eliminated, and there is no possibility that the flexible resin 68 slides and hinders the sliding of the optical fiber for detection light 14a. be able to.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. Below, the same reference numerals are assigned to the same components as those in the second embodiment, and the description thereof is omitted, and only the parts different from those in the second embodiment will be described.

In the third embodiment, the following are employed as the plurality of optical fibers for detection light 14a. That is, the coating 28 of the detection light optical fiber 14 a is formed so as to cover the outer peripheral surface of the clad 26 with a fluororesin such as ETFE. However, the interface which is the contact surface between the coating 28 and the clad 26 is not physically or chemically bonded. That is, in the interface between the coating 28 and the cladding 26, and is slidable in the direction of the two layers the optical fiber longitudinal axis O ₂ to each other.

When the optical fiber 14a for detection light having such a configuration is used, it is incorporated into the outer cylindrical member 58 as shown in FIG. That is, the cladding 28 of the detection light optical fiber 14a with the reflection portion 20 attached to the tip of the detection light optical fiber 14a and the flexible resin 68 are removed from the tip of the probe 1. The fixing portion 70 is held and fixed by adhesion. Here, the inner wall of the outer tubular member 58 and the coating 28 of the optical fiber for detection light 14 a are firmly bonded and held via the flexible resin 68. When the exterior cylindrical member 58 is formed of, for example, PTFE or the like, and the coating 28 is formed of a fluororesin or the like having a low bondability such as ETFE, the inner wall of the exterior cylindrical member 58 and the outer surface of the coating 28 are For example, it is desirable that a surface treatment that improves adhesion to the flexible resin 68 such as Na etching or plasma treatment is performed.

With this configuration, a part of the interface 72c where the clad 26 and the coating 28 of the optical fiber for detection light 14a are adjacent is fixed within a desired range, and the probe longitudinal axis of the other outer cylindrical member 58 is fixed. interface 72c in the entire length direction of the O ₁ functions as a sliding part to be slidable in the optical fiber longitudinal axis O ₂ direction detection-light optical fiber 14a with respect to the outer tubular member 58.

In FIG. 11, for convenience of illustration, the interface 72c between the clad 26 and the coating 28 is shown as having a thickness, but this is a contact portion between two layers and has a substantial thickness. No.

Also in the probe 1 of the shape detection device according to the third embodiment having the above-described configuration, the interface 72c between the clad 26 and the coating 28 is slidable with each other, like the

interfaces

72a and 72b in the first and second embodiments. Since the optical fiber for detection light 14a cannot be expanded and contracted, the exterior cylindrical member 58 can be curved with a desired curvature.

As described above, in the shape detection apparatus according to the third embodiment, each of the plurality of detection light optical fibers 14a covers the core 24, the clad 26 covering the outer peripheral surface of the core 24, and the outer peripheral surface of the clad. The sliding portion is an interface 72c where the coating 28 and the clad 26 in each of the plurality of optical fibers for detection light 14a are adjacent to each other.
In this case, a part of the interface 72c where the coating 28 and the clad 26 are adjacent to each other in each of the plurality of detection light optical fibers 14a is fixed within a desired range, and the other longitudinal directions of the plurality of detection light optical fibers 14a are fixed. interface 72c is a sliding portion in the entire length direction of the optical fiber longitudinal axis O ₂ is.
Accordingly, the sliding of the detected portion 22 in the direction of the optical fiber longitudinal axis O ₂ exceeding the proper range can be restricted, and the sliding of each of the plurality of optical fibers for detection light 14a can be independently performed. Can be done.

Here, at least one of the surface of the inner wall of the outer cylindrical member 58 and the surface of the coating 28 of each of the plurality of optical fibers for detection light 14 a is subjected to surface modification that improves adhesion to the flexible resin 68. Yes.
Therefore, sliding at the interface between the outer cylindrical member 58 and the flexible resin 68 or the interface between the coating 28 and the flexible resin 68 can be eliminated, and the flexible resin 68 is slid to detect light. The possibility of hindering the sliding of the optical fiber 14a can be eliminated.

[Fourth Embodiment]
The fourth embodiment of the present invention will be described below. Below, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted, and only the parts different from the first embodiment will be described.

In the first embodiment, the flexible resin 68 is lumen 66, which had been filled over substantially the entire length of the direction of the probe longitudinal axis O ₁ of the outer tubular member 58, in the fourth embodiment, As shown in FIG. 12, only a part of the outer cylindrical member 58 in the direction of the probe longitudinal axis O ₁ , preferably in the vicinity of the detected portion 22, is filled. In order to allow such partial filling of the flexible resin 68, the exterior cylindrical member 58 is placed at a desired position, for example, in the vicinity of the detected portion 22, inside the exterior cylindrical member 58. A hole (or notch) 74 through which the flexible resin 68 can be supplied is provided. After filling with the flexible resin 68, the hole 74 is closed by attaching a protective tube 76 at least outside the hole 74 (part in the longitudinal axis direction).

Further, detection-light optical fiber 14a of the reflective portion 20 is attached at its distal end is held fixed to the outer tubular member 58 of the fixing portion 70, the interface 72d is the direction of the probe longitudinal axis O ₁ of the outer tubular member 58 Is slidable over the entire length.

The interface 72d is not limited to the contact surface between the exterior cylindrical member 58 (lumen 66) and the flexible resin 68, and may be the contact surface between the flexible resin 68 and the coating 28.

As described above, in the shape detection device according to the fourth embodiment, the flexible resin 68 is filled only in the vicinity of at least one detected portion 22 provided for each of the plurality of shape detection sensors 10, and the sliding portion. Is the total length in the longitudinal axis direction of the exterior tubular member 58 at the interface 72d where the inner wall of the exterior tubular member 58 and the outer surface of the flexible resin 68 are adjacent to each other. The outer cylindrical member 58 is fixed to a portion other than the flexible resin 68.
Accordingly, the sliding of the detected portion 22 in the direction of the optical fiber longitudinal axis O ₂ exceeding the proper range can be restricted, and the sliding of each of the plurality of optical fibers for detection light 14a can be independently performed. Can be done.
Furthermore, since the interface 72d is shorter than the interfaces 72a to 72c in the first to third embodiments, the resistance of the sliding surface at the time of bending can be suppressed, and a more reliable shape detection device. Can be provided.

Here, the shape detection apparatus according to the fourth embodiment further includes at least one hole 74 that is provided in a part of the exterior cylindrical member 58 and can fill the exterior cylindrical member 58 with the flexible resin 68. Prepare.
Thereby, the flexible resin 68 can be filled easily.

Although various embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be made without departing from the scope of the present invention. . For example, those skilled in the art can conceive a shape detection device that combines the embodiments.

Claims

A light source unit that emits detection light, an optical fiber for shape detection that guides the detection light emitted from the light source unit, and the optical fiber that changes the characteristics of the detection light according to the curvature of the optical fiber. A plurality of shape detection sensors each having at least one detected portion and a light detection portion for detecting detection light guided through the optical fiber;
A shape calculation device for calculating a curved shape of the detected portion based on a change in characteristics of detection light detected by a plurality of light detection portions of the plurality of shape detection sensors;
An exterior cylindrical member in which at least a part of each of the plurality of optical fibers of the plurality of shape detection sensors is installed;
A flexible resin filled between the outer cylindrical member and the plurality of optical fibers, at least a portion of the outer cylindrical member in the longitudinal axis direction;
A sliding portion that allows the plurality of optical fibers to slide independently in the longitudinal direction of the optical fiber;
A shape detection apparatus.
The shape detection device according to claim 1, wherein the sliding portion is an interface where an inner wall of the exterior tubular member and an outer surface of the flexible resin are adjacent to each other.
A part of the interface where the inner wall of the exterior cylindrical member and the outer surface of the flexible resin are adjacent is fixed within a desired range, and the other length of the exterior cylindrical member in the entire length in the longitudinal axis direction is fixed. The shape detection device according to claim 2, wherein an interface is the sliding portion.
The inner wall of the outer tubular member is an inner wall of a plurality of lumens provided in the outer tubular member,
One of the plurality of optical fibers is disposed in each of the plurality of lumens,
The shape detection device according to claim 3, wherein each of the plurality of lumens is filled with the flexible resin.
The shape detection device according to claim 4, wherein inner walls of the plurality of lumens are formed of a fluororesin capable of reducing sliding resistance of the interface between the inner walls of the plurality of lumens and the flexible resin.
The shape detection device according to claim 4, wherein an outer surface of each of the plurality of optical fibers is subjected to surface modification that improves adhesion to the flexible resin.
The shape detection device according to claim 1, wherein the sliding portion is an interface where the flexible resin and each of the plurality of optical fibers are adjacent to each other.
A part of the interface where the flexible resin and each of the plurality of optical fibers are adjacent is fixed within a desired range, and the interface is slid over the entire length of the exterior cylindrical member in the longitudinal axis direction. The shape detection apparatus according to claim 7, which is a moving part.
The outer surface of each of the plurality of optical fibers is formed of a fluororesin that can reduce sliding resistance at the interface between the outer surface of each of the plurality of optical fibers and the flexible resin. The shape detection apparatus described.
The shape detection device according to claim 8, wherein the surface of the inner wall of the exterior tubular member is subjected to surface modification that improves adhesion to the flexible resin.
Each of the plurality of optical fibers has a core, a clad covering the outer peripheral surface of the core, and a coating covering the outer peripheral surface of the clad,
The shape detection device according to claim 1, wherein the sliding portion is an interface where the coating and the cladding in each of the plurality of optical fibers are adjacent to each other.
A part of the interface where the coating and the clad are adjacent to each other in the plurality of optical fibers is fixed within a desired range, and the interface is the sliding part in the entire length in the longitudinal axis direction of the other optical fibers. The shape detection device according to claim 11.
The surface modification which improves the adhesiveness with respect to the said flexible resin is given to at least one of the surface of the inner wall of the said exterior cylindrical member, and the surface of the said coating | cover of each of these optical fiber. The shape detection apparatus described.
The flexible resin is filled only in the vicinity of the at least one detected portion provided in each of the plurality of shape detection sensors,
The sliding portion is the entire length in the longitudinal axis direction of the exterior tubular member at the interface where the inner wall of the exterior tubular member and the outer surface of the flexible resin are adjacent to each other.
The shape detection device according to claim 1, wherein each of the plurality of optical fibers is fixed to the exterior tubular member at a portion other than the flexible resin.
The shape detection device according to claim 14, further comprising at least one hole provided in a part of the outer tubular member and capable of filling the flexible resin in the outer tubular member.
The shape detection device according to claim 1, further comprising a rigidity reinforcing member capable of reducing buckling or twisting of the outer tubular member.
The shape detection device according to claim 16, wherein the rigidity reinforcing member is a braid in which a wire is knitted.
The shape detection apparatus according to claim 16, wherein the rigidity reinforcing member is a coil in which a wire is formed in a spiral shape.
The shape according to claim 1, wherein at least one of the plurality of shape detection sensors shares the light source unit and / or the light detection unit with at least one other of the plurality of shape detection sensors. Detection device.
Each of the plurality of optical fibers is disposed along the longitudinal axis direction of the insertion portion of the endoscope apparatus,
The shape detection device according to claim 1, wherein the shape calculation device calculates a curved shape of the insertion portion based on the calculated curved shape of each detected portion.