KR101797352B1 - Force sensor using optical fiber and capillary, manufacture method of the same, medical device including the same - Google Patents

Abstract

The present invention relates to a force sensor using an optical fiber and a capillary, comprising: an optical fiber having a coating and at least one clad-free end; A capillary having an inner space formed along the longitudinal direction and having one end inserted into the inner space and outputting a part of an optical signal transmitted from the other side of the optical fiber through optical coupling with the inserted end; And an arithmetic unit for calculating the external force based on the optical signal applied to the other side of the optical fiber and the optical signal reflected at one end of the optical fiber and returned to the other side when the one end moves along the internal space by an external force So that the core and the capillary tube where the optical coupling is generated can be aligned coaxially with each other, so that the distance between the core and the capillary tube can be kept constant and the external force can be more accurately sensed.

Description

TECHNICAL FIELD [0001] The present invention relates to a force sensor using an optical fiber and a capillary tube, a method of manufacturing the same, and a medical instrument including the same. [0002]

The present invention relates to a force sensor using an optical fiber and a capillary tube, a method of manufacturing the same, and a medical instrument including the same, wherein the core of the optical fiber is inserted into an inner space formed along the longitudinal direction of the capillary tube, To a force sensor using an optical fiber and a capillary tube capable of sensing a force more accurately, a method of manufacturing the same, and a medical instrument including the same.

Generally, a catheter is a medical device used to insert a tube into a patient's body to perform high-frequency treatment on the affected part, to inject a medical substance into the body, and to discharge body fluids and the like to the outside.

In the case of performing the catheter using the catheter as described above, when the peak of the catheter exerts excessive pressure on the affected part of the patient, the affected part is damaged. When the pressure is too small, the affected part may not be properly treated. It is necessary to measure the pressure applied to the affected part and perform the procedure accordingly.

Particularly, in the case of a catheter for performing a delicate portion such as a blood vessel, if the pressure applied to the blood vessel by the catheter can not be precisely measured, a medical accident may occur while penetrating the blood vessel.

Accordingly, various types of sensors for measuring the pressure applied to the peak of the catheter have been proposed.

Currently used sensors are usually force sensors using an electric pressure sensitive device whose output varies according to external force.

However, the force sensor using the electric pressure sensor does not change a large amount of current when a small external force is applied. In order to precisely measure the current change, a high-priced device is required. There is a problem in that the size of the catheter becomes large when the size of the catheter is increased by increasing the size of the catheter. Therefore, a force sensor and a catheter using the force sensor are needed.

Korean Patent Registration No. 10-1509397 discloses a force sensor using an optical fiber and a catheter using the force sensor.

According to Korean Patent Registration No. 10-1509397, external force is generated by arranging a first optical fiber and a second optical fiber side by side, and then, when an external force is applied, the first optical fiber and the second optical fiber overlap each other, Quot; is calculated by using the fact that the call is changed.

However, since the first optical fiber and the second optical fiber are provided on the 탆 scale, it is very difficult to arrange the first optical fiber and the second optical fiber side by side at regular intervals because of the attractive force due to the van der Waals force and the electrostatic force.

Due to such a problem, the force sensor according to Korean Patent Registration No. 10-1509397 is not only difficult to manufacture, but also has a problem that an error of force measurement is very large even if it is manufactured.

Korean Patent No. 10-1509397

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide an optical fiber which is easy to align by inserting a core of an optical fiber into an inner space formed along a length direction of the capillary, A force sensor using the optical fiber and a capillary coupler capable of sensing more accurately, a method of manufacturing the same, and a medical instrument including the same.

The above and other objects of the present invention can be achieved by a force sensor using an optical fiber and a capillary tube according to the present invention, a method of manufacturing the same, and a medical instrument including the same.

A force sensor according to an embodiment of the present invention includes: an optical fiber having a coating and at least one clad-free end; A capillary having an inner space formed along the longitudinal direction and having one end inserted into the inner space and outputting a part of an optical signal transmitted from the other side of the optical fiber through optical coupling with the inserted end; And an arithmetic unit for calculating the external force based on the optical signal applied to the other side of the optical fiber and the optical signal reflected at one end of the optical fiber and returned to the other side when the one end moves along the internal space by an external force .

And a guiding part for guiding one end of the optical fiber to be inserted into the internal space of the capillary tube, the optical fiber corresponding to the outer diameter of the optical fiber and the outer diameter of the capillary tube, the optical fiber being inserted into one side and the capillary tube being inserted into the other side can do.

The optical fiber may further include a stiffener applied to a boundary between the one end and the remaining area from which the cladding and the clad are removed.

The capillary tube may further include an adhesive portion which is provided as an elastic material to adhere the guide portion to the outer surface of the clad and to adhere the outer surface of the capillary to the guide portion.

And a reflective layer formed at an end of the one end.

And a coating layer formed on an outer surface of the capillary.

The diameter of the inner space may correspond to the diameter of the one end.

In addition, the one end may have both the cladding and the clad removed and only the core exposed.

A method of manufacturing a force sensor according to an embodiment of the present invention includes: a coating removal step of removing a coating on one end of an optical fiber; A clad removing step of removing at least a part of the clad exposed by the clad removing step; A capillary preparing step of preparing a capillary along which the cladding and the cladding-free optical fiber are inserted; An optical fiber assembling step of inserting an optical fiber having a cladding and clad at one end thereof on one side of a guide part having an inner diameter corresponding to an outer diameter of the optical fiber and an outer diameter of the capillary, and bonding the optical fiber and the capillary using an elastic adhesive; And a capillary assembling step of inserting the capillary tube into the other side of the guide section and bonding the capillary tube to the guide section using an elastic adhesive, wherein one end of the optical fiber is inserted into the capillary through the optical fiber assembling step and the capillary assembling step, And is inserted into the space.

After the clad removing step, the method may further include a step of applying a stiffener to a boundary between the one end and the remaining region from which the clad and the clad are removed.

A medical device according to an embodiment of the present invention includes a force sensor according to an embodiment of the present invention, and can measure a force applied to an end portion using the force sensor.

According to the present invention, the core of the optical fiber is inserted into the inner space formed along the longitudinal direction of the capillary so that the core and the capillary can be coaxially aligned. As a result, the distance between the core and the capillary is kept constant, so that the external force can be more accurately sensed.

Further, the stress applied to the end portion of the clad can prevent the stress from being concentrated on a part of the core located at the end portion of the clad and being broken.

Further, the core can be easily inserted into the inner space by the guide portion connecting the outer surface of the clad and the outer surface of the capillary tube.

Further, by the reflection layer formed at the end of the core, the optical signal can be effectively reflected at the end of the core, so that the external force can be measured more easily.

Moreover, the capillary is effectively prevented from being damaged by the coating layer formed on the outer surface of the capillary forming the inner space.

FIG. 1 is a perspective view of a force sensor using an optical fiber and a capillary according to an embodiment of the present invention,
2 is a cross-sectional view of a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention,
FIG. 3 illustrates a medical device including a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention,
4 is a flowchart of a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention,
5 is a view illustrating a step of removing a cover of a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention,
6 is a diagram illustrating a clad removing step in a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention,
7 is a view showing a reinforcing step of a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention,
8 is a diagram illustrating a capillary preparation step of a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention,
9 illustrates an optical fiber assembly step of a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention.
10 illustrates a capillary assembling step of a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention.

Hereinafter, a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention, a method for manufacturing the same, and a medical instrument including the same will be described in detail with reference to the accompanying drawings.

In the following description, only parts necessary for understanding the present invention will be described, and descriptions of other parts may be omitted so as not to disturb the gist of the present invention.

In addition, terms and words used in the following description and claims should not be construed to be limited to ordinary or dictionary meanings, but are to be construed in a manner consistent with the technical idea of the present invention As well as the concept.

FIG. 1 is a perspective view of a force sensor using an optical fiber and a capillary according to an embodiment of the present invention, and FIG. 2 is a sectional view of a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention.

1 and 2, a force sensor using an optical fiber and a capillary coupler according to an exemplary embodiment of the present invention includes an optical fiber 110, a capillary 120, a calculator 130, a stiffener 140, (150), a bonding portion (160), and a reflective layer (170).

The optical fiber 110 is a general optical fiber composed of a triple structure of a core 111, a clad 112 and a clad 113. The optical fiber 110 is an optical fiber having a triple structure of a core 111, The clad 112 and the clad 113 formed on the end portion are removed.

The clad 112 and the cover 113 are preferably removed by a length of about 1 mm to 2 mm, respectively, so that the core 111 at one end is exposed to the outside.

In addition, although it is preferable that the clad 112 is entirely removed so as to expose only the core, it may remain at a thickness of 9 탆 or less so that optical coupling can be performed. Therefore, in the following description, the core exposed at one end includes not only the pure core but also the remaining cladding with a thickness capable of optical coupling.

The capillary tube 120 forms an internal space sp along the longitudinal direction so that the core 111 described above is inserted into the internal space sp and the optical coupling by the optical coupling in the overlapping region of the capillary and the core A part (first optical signal: s1) of the signal exits to the capillary 120.

For this purpose, the capillary is preferably a silica material such as a core so as to be able to transmit an optical signal.

As described above, by inserting the core 111 into the inner space sp formed in the capillary tube 120, the core 111 and the capillary tube 120 can be easily arranged coaxially, that is, have.

According to Korean Patent Registration No. 10-1509397, which is a prior art of the present invention, since the optical fiber 110 is provided in a 탆 scale, a plurality of optical fibers 110 are spaced apart from each other by a certain distance due to van der Waals force, There is a very difficult problem to arrange to have side by side.

According to the coupling structure of the core 111 and the capillary tube 120 according to the present invention described above, by inserting the core 111 into the inner space sp formed in the capillary tube 120, the core 111 and the capillary tube 120 The external force can be more accurately sensed because the distance between the core 111 and the capillary tube 120 is kept constant.

Although the inner space sp of the capillary tube 120 is shown without a gap in FIG. 1, it is preferable that the inner circumferential surface of the capillary tube 120 is spaced apart from the outer surface of the core 111 by a predetermined distance. When the capillary tube 120 and the core 111 are too close to each other, the capillary tube 120 and the core 111 are in contact with each other when the capillary tube 120 is moved. However, it is preferable to be spaced within a few micrometers for optical coupling between the core and the capillary.

3, when a vertical force F is applied to the tip 1100 of the catheter 1000, an external force is transmitted to the capillary tube 120. By this external force, the capillary tube 120 moves vertically Direction. The movement of the capillary 120 causes the length of the surface of the inserted core 111 facing the surface of the capillary tube 120 forming the inner space sp, that is, the length of the core 111 overlapping with the capillary tube Change. The amount of the first optical signal s1 that exits through the capillary 120 is changed according to the change of the length according to the optical coupling.

When the capillary 120 moves along the longitudinal direction of the core 111 by the external force, the calculating unit 130 calculates the optical signal s2 based on the optical signal supplied to the optical fiber and the second optical signal s2 reflected from the end of the core, The length of the core 111 inserted into the inner space sp is calculated and the external force is calculated based on the length of the core 111 to be connected to the other end of the optical fiber 110.

As described above, when the capillary tube 120 is moved by the external force, the length of the core 111 overlapping with the capillary tube 120 is changed, The light amount of the signal s2 is changed. The calculation unit 130 calculates the changed length of the core 111 overlapping with the capillary 120 based on the light quantity of the second optical signal s2 and calculates the external force using the calculation result.

That is, the calculating unit 130 calculates the overlapped length by substituting the light amount of the second optical signal s2 transmitted from the end of the current core 111 into the overlapped length table according to the amount of light stored in advance, And calculates the external force currently applied by substituting the length of the superposed core 111 calculated in the external force table according to the changed length of the core 111. Of course, it is also possible to directly calculate the external force with the light amount measured using the external force table according to the light amount.

The stiffener 140 is applied to surround the core located at the boundary by preventing stress from concentrating on the core 111 located at the boundary between the area where the cladding and the clad are removed and the remaining area that is not removed. The reinforcing material 140 may be made of an elastic material, and the elasticity of the reinforcing material effectively prevents the stress from concentrating on the core 111 at the boundary.

The guide unit 150 connects the outer surface of the optical fiber 110 and the outer surface of the capillary tube 120 to guide the insertion of the core 111 into the inner space sp of the capillary tube. With this guide portion 150, it is very easy to insert the core 111 into the inner space sp.

The guide portion 150 may be made of silica as in the case of the capillary tube 120. Therefore, when the core 111 and the guide 150 are too close to each other, optical coupling between the guide 150 and the core 111 may be generated, so that the guide 150 and the core 111 are at least 9 Mu] m or more.

The diameter of the guide portion 150 is set to correspond to the entire outer diameter (about 250 μm) of the optical fiber 110 so that the guide portion 150 can be spaced apart from the core 111 by a sufficient distance, 250 占 퐉).

The adhesive portion 160 adheres the outer surface of the optical fiber 110 to the guide portion 150 and adheres the outer surface of the capillary tube 120 to the guide portion 150 and is made of an elastic material.

That is, when the capillary tube 120 is fixed to the guide portion 150 by the adhesive portion, the capillary tube can be moved when an external force is applied, and elasticity such as a photo-curable resin or PDMS can be returned to the original position It is preferable to use an adhesive.

The reflective layer 170 is formed at the end of the core 111 to effectively reflect the optical signal that has not escaped to the capillary by optical coupling with the capillary. When such a reflective layer 170 is provided, a larger amount of optical signal than that reflected from the end of the core is reflected without the reflective layer, and effectively returns to the other end of the optical fiber, so that measurement of the optical signal is facilitated, have.

Although not shown in the drawing, a coating layer may be formed on the outer surface of the capillary tube to receive the damage of the capillary tube due to friction between the guide portion and the capillary tube when the capillary tube 120 is moved by an external force.

A force sensor according to an embodiment of the present invention including an optical fiber 110, a capillary tube 120, and a calculation unit 130 may include a force sensor according to an embodiment of the present invention, The core 111 of the capillary tube 120 may be inserted into the inner space sp formed along the longitudinal direction of the capillary tube 120 so that the core 111 and the capillary tube 120 are coaxially aligned. Thus, the external force can be more accurately sensed because the distance between the core 111 and the capillary tube 120 is kept constant.

Further, since the reinforcing member 140, the guide unit 150, the adhesion unit 160, the reflection layer 170, and the coating layer 180 are further included, it is possible to easily assemble the force sensor, to prevent breakage, It is possible to provide an effect of facilitating the operation.

Hereinafter, a medical device including a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention will be described in detail with reference to a catheter as an example.

FIG. 3 illustrates a catheter including a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention.

3, a catheter 1000 including a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention includes a tip 1100 and a pipe 1200, and a force according to an embodiment of the present invention. Sensor 100 as shown in FIG.

The tip 1100 is connected to the upper end of the piping 1200, which will be described later, and is made of metal. Inside the tip 1100, a force sensor 100 using an optical fiber and a capillary coupler according to an embodiment of the present invention is installed.

The pipe 1200 is connected to the lower end of the tip 1100 and is provided with an elastic agent. An optical fiber 110 of a force sensor 100 using an optical fiber and a capillary coupler according to an embodiment of the present invention is installed in the pipe 1200.

When the normal force F is applied to the tip 1100 described above, the capillary 120 is moved by the relative displacement of the tip 1100 and the pipe 1200, The length is changed. The change in the length of the superimposed core 111 changes the amount of light of the second optical signal s2 reflected and transmitted from the end of the core 111. The calculating unit 130 calculates the vertical force, do.

Thus, according to the catheter 1000 according to one embodiment of the present invention including the tip 1100, the plumbing 1200, and the force sensor 100 according to one embodiment of the present invention, the tip 1100 of the catheter The applied external force can be more accurately sensed.

Hereinafter, a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 4 is a flowchart illustrating a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention. FIG. 5 is a view illustrating a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention. 6 is a view illustrating a clad removal step of a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention, and FIG. 7 is a view illustrating a clad removal step of the optical fiber according to an embodiment of the present invention. And FIG. 8 is a view illustrating a step of assembling an optical fiber in a method of manufacturing a force sensor using an optical fiber and a capillary tube according to an embodiment of the present invention. FIG. The capillary assembling step of the method of manufacturing a force sensor using an optical fiber and a capillary coupler according to an embodiment of the present invention.

As shown in FIG. 4, a method of fabricating a force sensor using an optical fiber and a capillary coupler according to an embodiment of the present invention includes a covering removal step (S110), a clad removing step (S120), a reinforcing step (S130) Step S140, an optical fiber assembly step S150, and a capillary assembly step S160.

As shown in FIG. 5, the coating removal step (S110) is a step of removing the coating 113 formed at one end of the optical fiber 110. [ In this coating removal step (S110), the coating 113 is completely removed from the one end of the optical fiber 110 to a length of about 1 mm to 2 mm.

6, the clad removing step S120 includes etching the clad 112 exposed by the cladding removing step S110 so that the core 111 is exposed at one end of the optical fiber 110, Is removed.

In this etching process, the optical fiber is fixed to a PDMS (polydimethylsiloxane) holder, and one end of the substrate with the coating 113 removed is immersed in an aqueous solution of HF (Hydrofluoric Acid) or ammonium fluoride (NH ₄ F) In a mixed BOE (Buffered Oxide Etch) solution.

At this time, the clad is completely removed or etched so as to remain at a thickness (about 9 mu m) or less for allowing photocoupling.

As shown in FIG. 7, the reinforcing step S130 is performed by using an elastic material such that the stress is concentrated on a portion of the core 111 located at a region where the coating and the clad 112 are removed, Is performed after the above-described clad removing step (S120).

By this reinforcing step (S130), the problem that the stress is concentrated on the core located at the boundary and is broken is effectively prevented.

As shown in FIG. 8, a capillary 120 corresponding to the outer diameter of the optical fiber 110 is prepared (S140). The capillary 120 is made of the same or similar silica as the core. In the capillary preparation step, an inner space sp is formed along the longitudinal direction of the capillary, and the diameter of the inner space corresponds to the diameter of the exposed core through the coating removing step S110 and the clad removing step S120, (About 9 [mu] m) than a light-coupling possible distance (about 9 [mu] m). The inner space is formed at the center of the capillary so that the central axis of the inner space coincides with the central axis of the capillary.

When the optical fiber 110 and the capillary tube 120 are prepared as described above, the optical fiber and the capillary tube are assembled using the guide unit 150 having an inner diameter corresponding to the outer diameter of the optical fiber and the capillary tube, Can be completed.

More specifically, as shown in FIG. 9, the optical fiber is inserted into one side of the guide unit 150, and the guide unit and the optical fiber are coupled to each other using the adhesive unit 160.

10, a capillary tube is inserted into the other side of the guide part 150, and the guide part and the capillary tube are coupled to each other by using the adhesive part 160.

Since the core of the optical fiber is located at the center of the optical fiber and the inner space (sp) of the capillary is located at the center of the capillary, the core and the inner space are positioned facing each other by inserting the optical fiber and the capillary into the guide portion. It can be easily inserted.

Although FIG. 4 illustrates the capillary assembly step followed by the fiber assembly step, the capillary assembly step may be performed first.

In one embodiment of the present invention including the step of removing the coating (S110), the step of removing the clad (S120), the step of reinforcing (S130), the step of preparing the capillary (S140), the step of assembling the optical fiber (S150) According to the method of manufacturing a force sensor according to the present invention, a force sensor is easily manufactured.

The scope of the present invention is not limited to the above-described embodiments, but may be embodied in various forms of embodiments within the scope of the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

100: force sensor 110: optical fiber
111: core 112: clad
113: cloth 120: capillary tube
130: computing unit 140:
150: guide portion 160:
170: reflective layer 180: coating layer
s1: first optical signal s2: second optical signal
sp: internal space 1000: catheter
1100: Tip 1200: Piping
S100: Method of manufacturing force sensor S110: Step of removing coating
S120: Clad removing step S130: Reinforcement step
S140: capillary preparation step S150: optical fiber assembly step
S160: capillary assembly step

Claims (11)

An optical fiber having a coating and at least one end on which at least a part of the clad is removed;
And an inner space is formed along the longitudinal direction and the one end is inserted into the inner space and a part of the optical signal transmitted from the other side of the optical fiber through the optical coupling with the side of the inserted one end is outputted capillary; And
An operation unit for calculating the external force on the basis of the optical signal applied to the other side of the optical fiber and the reflected optical signal reflected at the one side end of the optical fiber and returned to the other side;
/ RTI >
Wherein a length of the capillary overlapping with the one end changes according to an external force, and the reflected optical signal changes according to a change in overlapping length of the capillary with the one end. The method according to claim 1,
And a guiding part for guiding one end of the optical fiber to be inserted into the internal space of the capillary tube, the optical fiber corresponding to the outer diameter of the optical fiber and the outer diameter of the capillary tube, the optical fiber being inserted into one side and the capillary tube being inserted into the other side Force sensor. The method according to claim 1,
Further comprising a stiffener applied to a boundary between the one end and the remaining region from which the clad and the clad are removed in the optical fiber. 3. The method of claim 2,
And a bonding portion provided in an elastic material for bonding the guide portion to the outer surface of the clad and bonding the outer surface of the capillary to the guide portion. The method according to claim 1,
And a reflective layer formed at an end of the one end. 3. The method of claim 2,
And a coating layer formed on the outer surface of the capillary. The method according to claim 1,
And the diameter of the inner space corresponds to the diameter of the one end. The method according to claim 1,
And the one end of the force sensor has both the cladding and the clad removed and the core exposed. A coating removal step of removing a coating on one end of the optical fiber;
A clad removing step of removing at least a part of the clad exposed by the clad removing step;
A capillary preparing step of preparing a capillary in which an inner space into which one end of a fiber and a clad-removed optical fiber are inserted is formed along the longitudinal direction;
An optical fiber assembly step of inserting an optical fiber having a cladding and a clad at one end thereof on one side of a guide part having an inner diameter corresponding to an outer diameter of the optical fiber and an outer diameter of the capillary, and bonding the optical fiber and the guide part using an elastic adhesive; And
A capillary assembling step of inserting the capillary tube into the other side of the guide section and bonding the capillary to the guide section using an elastic adhesive;
Wherein one end of the optical fiber is inserted into the internal space of the capillary through the optical fiber assembling step and the capillary assembling step so that the length of overlapping the capillary at one end of the optical fiber is changed according to external force A method of manufacturing a force sensor for assembly. 10. The method of claim 9,
Further comprising a reinforcement step of applying a reinforcement material to the boundary between the one end and the remaining area from which the clad and the clad have been removed after the clad removal step. 9. A medical device comprising a force sensor according to any one of claims 1 to 8, wherein the force applied to the end portion can be measured using the force sensor.

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