WO2020111487A1

WO2020111487A1 - Fiber scanning system

Info

Publication number: WO2020111487A1
Application number: PCT/KR2019/012593
Authority: WO
Inventors: 송철; 장연희; 임진택
Original assignee: 재단법인대구경북과학기술원
Priority date: 2018-11-29
Filing date: 2019-09-27
Publication date: 2020-06-04
Also published as: KR102224891B9; KR20200064638A; KR102224891B1

Abstract

The present invention relates to a fiber scanning system which, in a scanning optical fiber endoscope, has: a housing (50) of the scanning optical fiber endoscope; a cylindrical piezoelectric tube (100) inside the housing, wherein one end part (101) of the cylindrical piezoelectric tube is physically fixedly coupled to a piezoelectric tube coupling part (130) disposed in a predetermined position on the inner surface of the housing; and an optical fiber scanner (200) which is a cantilever type having only one side fixed inside the cylindrical piezoelectric tube. One end part (206) of the optical fiber scanner is physically coupled to the other end part (102) of the cylindrical piezoelectric tube by means of an optical fiber fixing part (110), and the other end part (205) of the optical fiber scanner is a free end. The optical fiber scanner fixed by means of the optical fiber fixing part (110) is disposed so as to pass, in a form of protruding from the optical fiber fixing part, through a frequency division part (120) coupled to the optical fiber fixing part (110). Therefore, the full length is reduced and thus a product can be made ultra-small and can be commercialized, uniform image information can be obtained by means of the frequency division part, and light can be irradiated in a uniform amount to a desired area.

Description

Fiber scanning system

The present invention relates to a fiber scanning system, and more specifically, by providing an asymmetric frequency separation unit, it is possible to obtain uniform image information and uniform light irradiation by separating frequencies, and to apply a Lissajous scan capable of scanning in various forms. It relates to a fiber scanning system.

The fiber scanner is a device for acquiring an external image using an optical fiber, and is easily applied to and manipulates a subject to be applied to various industrial fields.

In particular, in recent years, the scanner has been miniaturized, and has high utilization as a medical scanner and an endoscope scanner.

Looking at the prior art 1, Korean Patent Registration No. 10-1583277 relates to an optical fiber scanning probe using a MEMS-based frequency separator, without any additional structure for modulating the resonance frequency using modulation of the resonance frequency through the asymmetry of the scanner itself. Disclosed is a configuration providing a scanner for 2D optical scanning capable of realizing 2D driving with an input signal of.

When the above prior art 1 is described with reference to FIG. 1, an insulating layer 52 is formed on the upper side of the first fixing part 50 and the fixing block 51, and one end of the driving arm is fixed on the upper side of the insulating layer 52. do. That is, the first fixing part 50 to which one end of the driving arms is fixed is formed so that the insulating layer 52 is formed on the upper side of the fixing block 51 so that one end of the driving arms is not electrically connected to each other. It is formed in the form that one end of the driving arm is fixed to the upper side.

Therefore, according to the above prior art, the ends of the optical fiber are scanned by vibrating through a MEMS type plate type cantilever, and the asymmetrical MEMS cantilever can separate the resonant frequency of the optical fiber in two axial directions, and the stiffness of the cantilever is adjusted to control Control the difference.

However, in the prior art 1 as described above, the MEMS method has a limitation in miniaturization of a product, and the process of making an additional mass by the MEMS process is complicated, and thus there is a problem in terms of cost efficiency.

As another prior art 2, according to U.S. Patent US2008/0249369A1 (published Oct. 9, 2008), a probe 245 is disclosed that scans an optical fiber end by vibrating through a PZT type tube actuator 225, which is a tube actuator. It is an inverter structure in which the attachment portion of and the optical fiber is located behind the fixed point of the tube actuator.

That is, when the prior art 2 is described with reference to FIG. 2, a portion of the optical fiber, which is a scanner, is wrapped by a tube actuator, which has an advantage of reducing the overall length, but lacks a configuration to control the position of the probe in various forms. There is a limitation in controlling the position of the probe.

The present invention is to solve the above-mentioned problems, asymmetrical shape produced using an ultra-precision device Elastic chain The frequency separation part is provided in the piezoelectric tube to simplify the process process, and by adjusting the elasticity of the frequency separation part, the size of the resonant frequency and the degree to which the frequency is separated are controlled to obtain the resonant frequencies in the X-axis and Y-axis directions in a relatively simple manner. It is possible to separate and reduce the overall length of the fiber scanning housing, which makes it possible to miniaturize the product, and also obtains uniform image information by the frequency separation unit, and allows a uniform amount of light to be irradiated to the desired area. It is intended to provide a purpose.

However, the object of the present invention is not limited to the above-mentioned object, another object not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the present invention, in the scanning optical fiber endoscope, the housing 50 of the scanning optical fiber endoscope, the housing is provided with a cylindrical piezoelectric tube 100, one end portion 101 of the cylindrical piezoelectric tube Is physically fixedly coupled to the piezoelectric tube coupling part 130 disposed at a predetermined position on the inner surface of the housing, and the cantilever beam type optical fiber scanner 200 is fixed inside the cylindrical piezoelectric tube. The other end 206 is physically coupled by the optical fiber fixing portion 110 at the other end portion 102 of the cylindrical piezoelectric tube, and one end portion 205 of the optical fiber scanner is a free end and the optical fiber fixing portion 110 The optical fiber scanner fixed by) is disposed to pass through the frequency separation unit 120 coupled with the optical fiber fixing unit 110 in a form protruding from the optical fiber fixing unit.

In addition, a wire for applying electric current is connected to the piezoelectric tube 100, but the central axis of the piezoelectric tube is called the z axis, and perpendicular to the z axis, parallel to the cross section of the piezoelectric tube, and the vertical axis of each other is called the x axis and the y axis. When the piezoelectric tube is fixedly coupled to the housing, the electric wire is applied to the other end 102 of the piezoelectric tube to be deformed in the x-axis or y-axis direction to be deformed. do.

In addition, the frequency separating part 120 is a cylindrical shape surrounding the optical fiber scanner, and the frequency separating part has different elastic modulus in the x-axis direction and elastic modulus in the y-axis direction, so that the optical fiber is driven by the behavior of the piezoelectric tube. One end 205 of the scanner behaves in the form of a Lissajous.

In the above, the piezoelectric tube 100 is characterized in that the outer diameter is 1.0-2.0mm and the inner diameter is 0.6-1.3mm, and the length is about 4-10mm.

In addition, the frequency separation portion surrounding the outer diameter of the optical fiber scanner is attached with the optical fiber scanner and an adhesive, and the other end of the frequency separation portion is attached with the optical fiber fixing part 110 and an adhesive so that the frequency when the optical fiber scanner vibrates. The separator also vibrates.

In addition, as the curvature in the x-axis direction and the curvature in the y-axis direction are different from each other, the cross-sectional shape of the frequency separation unit may have different elasticity in the x-axis direction and elasticity in the y-axis direction.

In addition, in the cross-section of the frequency separation unit, elasticity in the x-axis direction and elasticity in the y-axis direction may be formed differently by applying different materials to the material in the x-axis direction and the material in the y-axis direction.

Further, as the x-axis direction and the y-axis length are different from each other, the elasticity in the x-axis direction and the elasticity in the y-axis direction may be formed differently.

In addition, the elasticity and y-axis in the x-axis direction are different from each other by differently applying the curvature of the surface forming the end portion of the cross section in the x-axis direction and the curvature of the surface forming the end portion of the cross-section in the x-axis direction. The elasticity of the direction can be formed differently

Further, when the length in the z-axis direction of the piezoelectric tube is L, the length in the z-axis direction of the frequency separation unit is L1, and when the length from the optical fiber fixing part of the optical fiber scanner to the free end is L2, L1 <L It is preferably formed of <L2, but may be used in the form of L1 <L2 <L or L<L1<L, if necessary.

In the above, the housing 50 includes a conical rear housing 51 whose diameter of the cross section gradually increases as it moves from the front end to the rear end, and a front housing 53 formed in a cylindrical shape, but the front end of the rear housing The outer surface protrudes in the longitudinal direction of the housing and has the same cross-section diameter.

The rear housing 51 is provided with a first engaging portion 52 protruding to have a predetermined length along an outer surface of the rear end of the rear housing; wherein the inner diameter of the first engaging portion is identical to the inner diameter of the rear housing In addition, the front housing 53 is provided with a second engaging portion 54 protruding to have a predetermined length along the outer surface of the front end of the front housing; provided with the outer diameter of the second engaging portion coincides with the outer diameter of the front housing As the outer diameter of the first coupling portion coincides with the inner diameter of the second coupling portion, the first coupling portion is fitted with the second coupling portion.

In addition, a lens mounting portion 300 is provided at the inner rear side of the front housing, but a lens is mounted in the first space portion so that light emitted from the end of the optical fiber scanner is focused to focus on a predetermined area.

In addition, by arranging two or more lenses in the first space portion, aberrations may be reduced compared to a single lens.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to this, the terms or words used in the specification and claims should not be interpreted in a conventional and lexical sense, and the inventor can properly define the concept of terms in order to best describe his or her invention. Based on the principle of being present, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

As described above, according to the present invention, an optical fiber scanner having an asymmetrical structure of a frequency separator is inserted into a piezoelectric tube for scanning, and the behavior of the optical fiber scanner is widely implemented by varying the elasticity in the axial direction of the cross section of the frequency separator. It is expected to have the effect of acquiring images in various forms.

1 shows an optical fiber scanning probe using a frequency separator having an asymmetric mass of the prior art.

Figure 2 shows a prior art optical fiber scanning probe shape.

Figure 3 shows a cross-section of the coupled state of the fiber scanning system of the present invention.

4 is a perspective view showing a coupled state of the fiber scanning system of the present invention.

5 schematically shows a state in which the asymmetric frequency separation unit of the present invention is coupled to an optical fiber fixing unit and an optical fiber scanner.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In this process, the thickness of the lines or the size of components shown in the drawings may be exaggerated for clarity and convenience.

In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to a user's or operator's intention or practice. Therefore, definitions of these terms should be made based on the contents throughout the present specification.

In addition, the following embodiments are not intended to limit the scope of the present invention, but are merely illustrative of the components presented in the claims of the present invention, and are included in the technical idea throughout the specification of the present invention and constitute the claims. Embodiments that include a substitutable component as an equivalent in the elements can be included in the scope of the present invention.

3 is a cross-sectional view showing a coupled state of the fiber scanning system of the present invention.

Referring to FIG. 3, in a scanning optical fiber endoscope, a housing 50 of a scanning optical fiber endoscope and a cylindrical piezoelectric tube 100 are provided in the housing, and one end 101 of the cylindrical piezoelectric tube is an inner surface of the housing Physically fixedly coupled to the piezoelectric tube coupling portion 130 disposed at a predetermined position of the cantilever-shaped optical fiber scanner 200 fixed to one side inside the cylindrical piezoelectric tube, the other end portion 102 of the optical fiber scanner ) Is physically coupled by the optical fiber fixing unit 110 at the other end 102 of the cylindrical piezoelectric tube, and one end 205 of the optical fiber scanner is a free end and is fixed by the optical fiber fixing unit 110 at this time. The optical fiber scanner is arranged to pass through the frequency separation unit 120 coupled to the optical fiber fixing unit 110 in a form protruding from the optical fiber fixing unit.

In more detail, the length in the z-axis direction of the piezoelectric tube 200 is referred to as L, the length in the z-axis direction of the frequency separation unit 120 is referred to as L1, and the optical fiber fixing unit of the optical fiber scanner is used. When the length to the free end is L2, L1 <L <L2 or L1 <L2 <L or L<L1<L.

In addition, a lens mounting portion 300 is provided on the inner rear side of the front housing, but a lens is mounted on the first space portion to condense light emitted from the end of the optical fiber scanner so that focus is focused on a predetermined area.

In the above, by arranging two or more lenses in the first space portion, aberration can be reduced compared to a single lens.

Attached Figure 4 shows a perspective view of the coupled state of the fiber scanning system of the present invention.

Referring to Figure 4, the piezoelectric tube 100 is connected to a wire that applies a current, the central axis of the piezoelectric tube is referred to as the z-axis, and perpendicular to the z-axis, parallel to the cross section of the piezoelectric tube, and perpendicular to each other x When the axis and the y axis are referred to, the other end portion 102 of the piezoelectric tube is bent in the x-axis or y-axis direction with respect to one end 101 where the piezoelectric tube is fixedly coupled to the housing so that the electric wire is deformed. It is arranged and power is applied.

At this time, the piezoelectric tube 100 has an outer diameter of 1.0-2.0mm, an inner diameter of 0.6-1.3mm, and preferably a length of about 4-10mm.

The attached FIG. 5 schematically shows a state in which the asymmetric frequency separation part of the present invention is coupled to an optical fiber fixing part and an optical fiber scanner.

5, the frequency separation unit 120 surrounding the outer diameter of the optical fiber scanner is bonded to the optical fiber scanner 200 and an adhesive 60, and the other end of the frequency separation unit is the optical fiber fixing unit 110 ) And the adhesive 60 to vibrate when the optical fiber scanner vibrates.

In addition, the cross-sectional shape of the frequency separation portion is preferably formed to have different elasticity in the x-axis direction and elasticity in the y-axis direction as the curvature in the x-axis direction and the curvature in the y-axis direction are formed differently.

Furthermore, in the present invention, one end 101 of the cylindrical piezoelectric tube is physically fixedly coupled by the piezoelectric tube coupling part 130 disposed at a predetermined position on the inner surface of the housing, and the other end 102 of the optical fiber scanner is cylindrically piezoelectric. The frequency separation unit 120 in a form protruding from the optical fiber fixing unit is physically coupled by the optical fiber fixing unit 110 at the other end portion 102 of the tube, and fixed by the optical fiber fixing unit 110. ).

Accordingly, when the piezoelectric tube is operated at the frequency of the resonance frequency band of the scanning wave separation unit, the displacement of the end of the optical fiber scanner is increased by the displacement of the small piezoelectric tube to scan the region of interest, and the optical fiber scanner end can be moved in a desired scan pattern. There is a feature that can scan the area to be scanned.

Although the present invention has been described in detail through specific embodiments, the present invention is specifically for describing the present invention, and the present invention is not limited to this, and by a person skilled in the art within the technical spirit of the present invention. It is clear that the modification and improvement are possible.

All simple modifications or changes of the present invention belong to the scope of the present invention, and the specific protection scope of the present invention will be clarified by the appended claims.

[Description of codes]

50 housing 51 rear housing

52 First coupling 53 Front housing

54 Second joint 60 Glue

100 piezoelectric tube 110 optical fiber fixture

120 Frequency separation 130 Piezoelectric tube coupling

200 fiber optic scanner

Claims

In the scanning optical fiber endoscope,

The housing 50 of the scanning optical fiber endoscope,

A cylindrical piezoelectric tube 100 is provided in the housing,

One end portion 101 of the cylindrical piezoelectric tube is physically fixedly coupled to the piezoelectric tube coupling portion 130 disposed at a predetermined position on the inner surface of the housing,

The inside of the cylindrical piezoelectric tube is provided with a cantilever-type optical fiber scanner 200 fixed on one side only.

The other end 206 of the optical fiber scanner is physically coupled by the optical fiber fixing unit 110 at the other end 102 of the cylindrical piezoelectric tube,

One end 205 of the optical fiber scanner is a free end

At this time, the optical fiber scanner fixed by the optical fiber fixing part 110 is arranged to pass through the frequency separation unit 120 coupled with the optical fiber fixing part 110 in a form protruding from the optical fiber fixing part. Scanning system.
The method of claim 1

The piezoelectric tube 100 is connected to a wire for applying a current

When the central axis of the piezoelectric tube is called the z axis, and perpendicular to the z axis and parallel to the cross section of the piezoelectric tube, the vertical axis of each other is called the x axis and the y axis.

With respect to one end portion 101 of which the piezoelectric tube is fixedly coupled to the housing, the electric wire is disposed and the power is applied so that the other end portion 102 of the piezoelectric tube is bent in the x-axis or y-axis direction to be deformed. Features a fiber scanning system.
The method of claim 2

The frequency separation unit 120 is a cylindrical shape surrounding the optical fiber scanner,

The frequency separation unit is characterized in that the elastic modulus in the x-axis direction and the elastic modulus in the y-axis direction are formed differently, so that one end 205 of the optical fiber scanner behaves in a resage shape by the behavior of the piezoelectric tube. Fiber scanning system.
The method of claim 2

The frequency separating part surrounding the outer diameter of the optical fiber scanner is attached with the optical fiber scanner and an adhesive, and the other end of the frequency separating part is attached with the optical fiber fixing part 110 and an adhesive to separate the frequency when the optical fiber scanner vibrates. Fiber scanning system characterized by vibrating together.
The method of claim 4

The cross-sectional shape of the frequency separation unit is characterized in that the curvature in the x-axis direction and the curvature in the y-axis direction are formed differently, so that the elasticity in the x-axis direction and the elasticity in the y-axis direction are different.
The method of claim 4

Fiber scanning characterized in that the x-axis direction material and the y-axis direction material are formed in different cross-sections of the frequency separation part to form elasticity in the x-axis direction and elasticity in the y-axis direction differently. system.
The method of claim 4

A fiber scanning system characterized in that the x-axis direction and the y-axis direction have different elasticity in the cross-section of the frequency separation unit, thereby forming elasticity in the x-axis direction and elasticity in the y-axis direction differently.
The method of claim 4

Elasticity in the x-axis direction and y-axis direction by differently applying a curvature of a surface forming a cross-section end in the x-axis direction and a curvature of a surface forming a cross-section end in the y-axis direction in the cross section of the frequency separation unit Fiber scanning system, characterized in that to form the elasticity of the different.
The method according to any one of claims 5 to 8,

When the length in the z-axis direction of the piezoelectric tube is L, the length in the z-axis direction of the frequency separation unit is L1, and when the length from the optical fiber fixing part of the optical fiber scanner to the free end is L2, L1 <L < A fiber scanning system characterized by being formed of L2 or L<L1<L2.