WO2020089969A1

WO2020089969A1 - Endoscope optical transducer, endoscope, and manufacturing method for endoscope optical transducer

Info

Publication number: WO2020089969A1
Application number: PCT/JP2018/040121
Authority: WO
Inventors: 優希伊藤
Original assignee: オリンパス株式会社
Priority date: 2018-10-29
Filing date: 2018-10-29
Publication date: 2020-05-07

Abstract

An endoscope optical transducer 1 is provided with: a ferrule 10 having an insertion hole H10; an optical element 30 that has a light-emission part 31 for generating an optical signal, with the light-emission part 31 disposed at a position opposing the insertion hole H10; and an optical fiber 20 that includes a core 21, a clad 22, and a coating layer 23, that has a tip part fitting to the insertion hole H10, and that transmits an optical signal. A side surface of the tip part of the optical fiber 20 has an outer plane 20SS, and the inner surface of the insertion hole H10 has an inner plane 10SS. An outer plane 32SS and the inner plane 10SS abut against each other.

Description

OPTICAL TRANSDUCER FOR ENDOSCOPE, ENDOSCOPE, AND METHOD FOR MANUFACTURING OPTICAL TRANSDUCER FOR ENDOSCOPE

The present invention relates to an optical transducer for an endoscope including an optical element, an optical fiber and a ferrule, an endoscope including an optical transducer including an optical element, an optical fiber and a ferrule, and an optical element, an optical fiber and a ferrule. And a method for manufacturing an optical transducer for an endoscope, comprising:

▽ The endoscope has an image pickup device such as a CCD at the tip of the elongated insertion portion. In recent years, use of an image pickup device having a large number of pixels for an endoscope has been studied. When an image sensor with a high pixel count is used, the amount of signals transmitted from the image sensor to the signal processing device (processor) increases. Therefore, optical signal transmission via an optical fiber by an optical signal is preferable in place of electrical signal transmission via a metal wiring by an electric signal. For optical signal transmission, an E / O type optical transducer (electrical-optical converter) that converts an electrical signal into an optical signal and an O / E type optical transducer (optical-electrical converter) that converts an optical signal into an electrical signal And are used.

As described in Japanese Unexamined Patent Publication No. 2015-068885, since the optical transducer for an endoscope is extremely small, accurate positioning is performed to efficiently optically couple an optical element and an optical fiber for transmitting an optical signal. And fixation are especially important. In order to accurately and easily position the optical element and the optical fiber, a ferrule having an insertion hole is provided on the wiring board on which the optical element is mounted. The optical element and the optical fiber can be easily positioned by inserting the optical fiber into the insertion hole of the ferrule.

However, if the center of the ferrule insertion hole does not exactly face the light emitting part of the optical element, the transmission efficiency of the optical transducer will decrease. In addition, the core that transmits the optical signal of the optical fiber may be eccentric from the center of the optical fiber. Then, even if the center of the insertion hole accurately faces the light emitting portion, the transmission efficiency of the optical transducer is reduced.

Therefore, it is preferable to insert the optical fiber into the ferrule insertion hole and then rotate the optical fiber to obtain the optimum angle with the best transmission efficiency, and fix the optical fiber to the ferrule at the optimum rotation angle. However, the optical fiber may rotate in the ferrule before being fixed, which may reduce the transmission efficiency. An optical signal output from an endoscope including an optical transducer having low transmission efficiency may be deteriorated.

Japanese Unexamined Patent Application Publication No. 2005-068885

Embodiments of the present invention provide an optical transducer for an endoscope with high transmission efficiency, an endoscope including an optical transducer with high transmission efficiency, and a method for manufacturing an optical transducer for an endoscope with high transmission efficiency. To aim.

The optical transducer for an endoscope of the embodiment has a first main surface and a second main surface facing the first main surface, and from the first main surface to the second main surface A ferrule having an insertion hole penetrating therethrough, an optical element having a light emitting portion for generating an optical signal, wherein the light emitting portion is arranged at a position facing the insertion hole, including a core, a clad, and a coating layer, An optical fiber for transmitting the optical signal, wherein a tip portion of the optical fiber is fitted into the insertion hole in a non-rotating state, and a side surface of the tip portion of the optical fiber has at least one outer plane, The inner surface of the insertion hole has at least one inner plane, and the outer plane and the inner plane are in contact with each other.

The endoscope of the embodiment includes an optical transducer, and the optical transducer has a first main surface and a second main surface facing the first main surface, and from the first main surface, A ferrule having an insertion hole penetrating to the second main surface, an optical element having a light emitting portion for generating an optical signal, the light emitting portion being arranged at a position facing the insertion hole, a core and a clad. And an optical fiber for transmitting the optical signal, which includes a cover layer and a tip portion fitted into the insertion hole in a non-rotatable state, and at least on a side surface of the tip portion of the optical fiber. There is one outer plane, and there is at least one inner plane on the inner surface of the insertion hole, and the outer plane and the inner plane are in contact with each other.

A method of manufacturing an optical transducer for an endoscope according to an embodiment includes a light emitting element having a light emitting portion for emitting an optical signal on a light emitting surface, a first main surface, and a second main surface facing the first main surface. And a ferrule having an insertion hole penetrating from the first main surface to the second main surface, the insertion hole having a core, a clad, and a coating layer, and having an inner flat surface on the inner surface, A method for manufacturing an optical transducer for an endoscope, wherein a tip portion having an outer flat surface on a side surface is fitted, and an optical fiber for transmitting the optical signal, wherein the tip portion is inserted into the insertion hole. An inserting step of inserting and fitting, a measuring step of generating the optical signal from the light emitting portion, measuring a light amount of the optical signal transmitted by the optical fiber, and an extracting step of removing the optical fiber from the insertion hole And a step of rotating the optical fiber about the optical axis , The inserting step, the measuring step, the removing step, and the rotating step are repeatedly performed, and the optimum angle selecting step of selecting the optimum angle that is the rotation angle at which the light amount is the largest; A reinsertion step of inserting the optical fiber into the insertion hole at an optimum angle and a fixing step of fixing the optical fiber to the ferrule are provided.

According to the embodiments of the present invention, it is possible to provide an optical transducer for an endoscope with high transmission efficiency, an endoscope including an optical transducer with high transmission efficiency, and a method for manufacturing an optical transducer for an endoscope with high transmission efficiency. ..

It is a perspective view of the endoscope of an embodiment. It is sectional drawing of the optical transducer of embodiment. FIG. 3 is an exploded view of a main part of the optical transducer of the embodiment. FIG. 4 is a cross-sectional view of the optical transducer according to the embodiment, taken along line IV-IV in FIG. 3. FIG. 5 is a cross-sectional view of the optical transducer according to the embodiment, taken along line VV of FIG. 3. 6 is a flowchart of a method for manufacturing the optical transducer of the embodiment. 9 is a perspective view of a ferrule of an optical transducer of a modified example 1. FIG. FIG. 8 is a sectional view taken along the line VIII-VIII in FIG. 7 of the ferrule of the optical transducer of the first modification. FIG. 9 is a sectional view taken along line IX-IX in FIG. 7 of the ferrule of the optical transducer of the first modification. FIG. 11 is a cross-sectional view of the main parts of the optical transducer of Modification 2. FIG. 11 is a cross-sectional view of a main part of an optical transducer of Modification 3; FIG. 11 is a cross-sectional view of the main parts of the optical transducer of Modification Example 4. FIG. 11 is a cross-sectional view of the main parts of an optical transducer of Modification Example 5. FIG. 13 is a cross-sectional view of the main parts of the optical transducer of Modification 6;

<Endoscope>
The endoscope 9 of the embodiment shown in FIG. 1 constitutes an endoscope system 6 together with a processor 5A and a monitor 5B. The endoscope 9 is disposed at the insertion portion 3, the grip portion 4 arranged at the base end portion of the insertion portion 3, the universal cord 4B extending from the grip portion 4, and the proximal end portion of the universal cord 4B. The connector 4C is provided. The insertion portion 3 includes a distal end portion 3A, a bending portion 3B extending from the distal end portion 3A, which is bendable to change the direction of the distal end portion 3A, and a flexible portion 3C extending from the bending portion 3B. Including. The grasping portion 4 is provided with a rotating angle knob 4A which is an operating portion for an operator to operate the bending portion 3B.

The universal cord 4B is connected to the processor 5A by the connector 4C. The processor 5A controls the entire endoscope system 6, performs signal processing on the image pickup signal, and outputs the image pickup signal as an image signal. The monitor 5B displays the image signal output by the processor 5A as an endoscopic image. Although the endoscope 9 is a flexible endoscope, it may be a rigid endoscope. The endoscope 9 may be medical or industrial.

An endoscope optical transducer 1 (hereinafter, referred to as “optical transducer 1”) and an imaging unit 2 are provided at a tip portion 3A of the endoscope 9. The optical transducer 1 converts the image pickup signal output by the image pickup unit 2 into an optical signal.

The optical signal is converted into an electric signal again by the O / E type optical module 8 arranged in the grip portion 4 by passing through the optical fiber 20 which passes through the insertion portion 3, and the conductor wire 20M which passes through the universal cord 4B. Is transmitted by way of. That is, the image pickup signal is transmitted through the optical fiber 20 in the small-diameter insertion portion 3, and is not inserted into the body and is thicker than the optical fiber 20 in the universal cord 4B having a small outer diameter limitation. It is transmitted by way of 20M.

Incidentally, when the O / E type optical module 8 is arranged in the connector 4C, the optical fiber 20 is inserted through the universal cord 4B.

As will be described later, the optical transducer 1 has good transmission efficiency. Therefore, the endoscope 9 has good signal transmission efficiency and little signal deterioration, so that the monitor 5B can display a good endoscopic image.

<Optical transducer for endoscope>
The endoscope optical transducer 1 according to the embodiment shown in FIG. 2 converts an electrical signal output from the imaging unit 2 into an optical signal, and then transmits the optical signal via the optical fiber 20.

In the following description, the drawings based on each embodiment are schematic, and the relationship between the thickness and width of each part, the ratio of the thickness of each part, the relative angle, etc. are actual. It should be noted that there is a difference in dimensional relationship and ratio between the drawings even if the drawings are different from each other. In addition, some components may not be illustrated.

The image pickup unit 2 includes a lens unit 50, a cover glass 41, an image pickup element 40, a three-dimensional wiring board 42, and a drive IC 43. The lens unit 50 includes a plurality of lenses and collects a subject image. The image pickup device 40 to which the cover glass 41 is adhered outputs an image pickup signal. The drive IC 43 arranged on the three-dimensional wiring board 42 outputs a drive signal based on the image pickup signal.

The optical transducer 1 includes an optical element 30, a wiring board 15, a ferrule 10, and an optical fiber 20.

The optical element 30 is a light emitting element such as a surface emitting laser chip or an LED chip having a light emitting section 31 for generating an optical signal on the light emitting surface 30SA. For example, the optical element 30 having a microscopic size of 250 μm × 300 μm in a plan view has a light emitting portion 31 having a diameter of 20 μm and an external electrode 32 on a light emitting surface 30SA. When a drive signal is input to the external electrode 32 from the drive IC 43, the light emitting unit 31 emits an optical signal in a direction perpendicular to the light emitting surface 30SA.

The wiring board 15 has a mounting surface 15SA and a rear surface 15SB facing the mounting surface 15SA, and is made of a transparent glass plate as a base. The external electrode 32 of the optical element 30 is bonded to the mounting surface 15SA.

The ferrule 10 has a first main surface 10SA and a second main surface 10SB that faces the first main surface 10SA, and an insertion hole that penetrates from the first main surface 10SA to the second main surface 10SB. There is H10. The tip of the optical fiber 20 is inserted into the insertion hole H10 and fixed by the adhesive 19. The material of the ferrule 10 that is a square pole or a cylinder is ceramic, silicon, glass, metal, or resin. A transparent plate such as a glass plate may be provided on the second main surface 10SB of the ferrule 10.

The optical fiber 20 includes a core 21 having a diameter of 50 μm that transmits light, a clad 22 having a diameter of 120 μm that covers the core 21, and a coating layer 23 having a diameter of 140 μm that covers the clad 22. That is, the thickness of the coating layer 23 is 10 μm.

As shown in FIGS. 3 to 5, there are six outer planes 20SS on the side surface of the tip of the optical fiber 20. That is, at the tip portion, there are six outer flat surfaces 20SS which are notched surfaces in which the coating layer 23 is notched. In addition, when the coating layer 23 at the tip portion is peeled off, the cutout surface is formed up to the clad 22.

The cross-sectional shape of the tip portion orthogonal to the optical axis O is a regular hexagon circumscribing the 120 μm diameter circle of the clad 22. This is also a regular hexagon inscribed in a circle having an outer diameter of 140 μm of the coating layer 23.

On the other hand, the inner surface of the insertion hole H10 of the ferrule 10 is a regular hexagon in which a cross-sectional shape orthogonal to the optical axis O is inscribed in a circle having a diameter of 150 μm. That is, there are six inner planes 10SS on the inner surface of the insertion hole H10. The inscribed circle of the insertion hole H10 is slightly larger than the inscribed circle of the tip of the optical fiber 20.

The tip of the optical fiber 20 is inserted into the insertion hole H10. The second main surface 10SB of the ferrule 10 is arranged on the rear surface 15SB of the wiring board 15 in a state where the insertion hole H10 faces the light emitting section 31. In other words, the extension line from the center of the core 21 at the tip of the optical fiber 20 (the optical axis C21 of the optical fiber 20) intersects the light emitting unit 31. Therefore, the optical signal generated by the light emitting unit 31 enters the optical fiber 20 by passing through the wiring board 15.

Note that if a wiring board based on an opaque material is used, a through hole is formed in the wiring board that serves as an optical path for optical signals. The optical element 30 may be mounted on the second main surface 10SB of the ferrule. That is, the wiring board is not an essential component of the optical transducer.

At the tip of the optical fiber 20 inserted into the insertion hole H10, the six outer planes 20SS are in contact with the respective six inner planes 10SS of the insertion hole H10, which face each other. The end of the optical fiber 20 is fitted in the insertion hole H10 so as not to rotate. That is, the tip of the optical fiber 20 is inserted in a state of being fitted exactly to the tip of the insertion hole H10.

The center CH10 of the insertion hole H10 of the ferrule 10 exactly faces the center C31 of the light emitting portion 31 of the optical element 30, and the center C21 of the core 21 of the optical fiber 20 matches the center C20 of the optical fiber 20. Therefore, even if the optical fiber 20 is rotated, the amount of light transmitted by the optical fiber 20 does not change.

However, in reality, as shown in FIGS. 4 and 5, the center C21 of the core 21 of the optical fiber 20 does not coincide with the center C20 of the optical fiber 20, and therefore the center CH10 of the insertion hole H10 of the ferrule 10 and the light emitting portion. The center C31 of 31 may deviate. Then, a part (or all) of the light beam (light flux) emitted from the light emitting unit 31 may enter the clad 22 around the core 21. In this case, when the optical fiber 20 is rotated, the area where the light beam (light flux) emitted from the light emitting unit 31 and the core 21 overlap with each other changes. That is, the amount of light incident on the core 21 changes. As a result, the amount of light transmitted by the optical fiber 20 changes.

As will be described later, in the optical transducer 1, the optical fiber 20 is inserted and fixed in the insertion hole H10 at the angle with the highest transmission efficiency among the six rotation angles. Therefore, the optical transducer 1 has high transmission efficiency. The endoscope 9 including the optical transducer 1 having high transmission efficiency does not have a possibility that the transmitted optical signal is deteriorated. Therefore, the endoscope system 6 including the endoscope 9 can display a good image.

<Method of manufacturing optical transducer>
A method of manufacturing the optical transducer 1 will be described with reference to the flowchart of FIG.

<Step S10> Inserting Step The tip of the optical fiber 20 is inserted into the insertion hole H10 of the ferrule 10 and fitted in a non-rotating state.

The inner surface of the cross section of the insertion hole H10 in the direction orthogonal to the optical axis is a regular hexagon. For example, the ferrule 10 is manufactured by cutting the ferrule wafer after a plurality of insertion holes H10 are formed in the ferrule wafer made of silicon by the DEEP-RIE method. Six cutout surfaces are formed in the coating layer 23 at the tip of the optical fiber 20. A cross section of the tip of the optical fiber 20 having six cutout surfaces (outer planes) orthogonal to the optical axis is a regular hexagon.

There are six rotation angles of the optical fiber 20 whose tip fits into the insertion hole H10. In the first step S10, the optical fiber 20 is fitted into the insertion hole H10 at any one of the six rotation angles.

<Step S20> Measuring Step An optical signal is generated from the light emitting section 31 of the optical element 30, and the light amount of the optical signal transmitted by the optical fiber 20 is measured. For example, the rear end of the optical fiber 20 is inserted into a photometer and the light quantity is measured.

<Step S30> Removal Step The optical fiber 20 is removed from the insertion hole H10.

<Step S40>
When the light amount measurement at all of the six rotation angles is completed (YES), the process proceeds to step S60. If the light amount measurement is not completed (NO), the process from step S50 is performed.

<Step S50> Rotation Step The optical fiber 20 is rotated about the optical axis O by 60 degrees.

<Step S60> Optimal Angle Selection Step The insertion step S10, the measurement step S20, the removal step S30, and the rotation step S50 are repeated 6 times. Then, the light quantity at six rotation angles can be obtained by six measurements. Then, from the six rotation angles, the rotation angle (optimum angle) having the largest light amount is selected.

<Step S70> Reinsertion Process The optical fiber 20 is inserted into the insertion hole H10 at the optimum angle. That is, the optical fiber 20 set to the rotation angle with the largest light quantity is inserted into the insertion hole H10.

<Step S80> Fixing Process The optical fiber 20 is fixed to the ferrule 10. For example, the uncured adhesive 19 is arranged around the insertion hole H10 of the first main surface 10SA, and the curing process is performed. Before the reinsertion step, the uncured transparent adhesive 19 may be injected into the insertion hole H10.

The optical fiber 20 is fitted in the insertion hole H10. That is, since the outer flat surface 20SS is in contact with the inner flat surface 10SS, it does not rotate after the reinsertion step.

According to the method of manufacturing the optical transducer of the present embodiment, the optical fiber 20 is inserted into the insertion hole H10 and fixed at an angle (optimal rotation state) having the best transmission efficiency among the six rotation angles (rotation state). Has been done. Therefore, the optical transducer 1 has high transmission efficiency.

<Modification>
The endoscope optical transducers 1A to 1F and the endoscopes 9A to 9F including the optical transducers 1A to 1F of the modified example are similar to the endoscope optical transducer 1 and the endoscope 9 and have the same effect. Therefore, the components having the same functions are designated by the same reference numerals and the description thereof will be omitted.

<Modification 1>
As shown in FIGS. 7 to 9, in the optical transducer 1A of the present modification, the insertion hole H10 of the ferrule 10A is connected to the first hole H10A having an opening in the first main surface 10SA and the first hole H10A. And a second hole H10B having an opening in the second main surface 10SB. The inner surface of the first hole H10A has a circular cross section orthogonal to the optical axis O. The inner surface of the second hole H10B is a regular hexagon in which a cross section orthogonal to the optical axis O has six inner planes 10SS. The circle of the first hole H10A is a regular hexagonal circumscribing circle of the second hole H10B. The shape of the inner surface of the second hole H10B may be a truncated cone, a regular hexagonal pyramid, or the like whose diameter increases toward the second main surface 10SB.

In other words, in the insertion hole H10, the relationship of (Formula 1) is established between the inner diameter A of the first hole H10A, the diameter B of the circumscribing circle of the second hole H10B, and the diameter C of the circumscribing circle of the optical fiber 20. To do.

A> C and B> C (Formula 1)

In the method of manufacturing the optical transducer 1A, in the insertion step S10, the tip of the optical fiber 20 is fitted into the second hole H10B. In the removing step S30, the tip portion is removed from the second hole H10B, but is not removed from the first hole H10A. That is, in the rotating step S50, the tip portion is not inserted into the second hole H10B, but is inserted into the first hole H10A.

It is not easy to insert the thin optical fiber 20 into the insertion hole H10 having an inner dimension that is substantially the same as the outer dimension of the optical fiber 20. However, in the method of manufacturing the optical transducer 1A, once the optical fiber 20 is inserted into the insertion hole H10, there is no need to perform the insertion work again.

The optical transducer 1A is easier to manufacture than the optical transducer 1.

<Modification 2 to Modification 5>
In the description of the modified examples below, the shape of the insertion hole of the ferrule and the tip of the optical fiber is the shape of a cross section orthogonal to the optical axis.

In the optical transducer 1B of the second modification shown in FIG. 10, the insertion hole H10 of the ferrule 10B is rectangular, and the optical fiber 20B has one outer plane. The inner shape of the insertion hole H10 is set in a state in which the notched optical fiber 20B is fitted.

In the optical transducer 1B, the optical fiber 20B is inserted into the insertion hole H10 at only two rotation angles. However, the optical fiber 20B is inserted and fixed to the ferrule 10B at an angle of the two rotation angles with which the transmission efficiency is good.

In the optical transducer 1C of the modified example 3 shown in FIG. 11, the insertion hole H10 of the ferrule 10C is a square (square), and the optical fiber 20C has two outer planes orthogonal to each other. The inner shape of the insertion hole H10 is set in a state in which the notched optical fiber 20C is fitted.

In the optical transducer 1C, the optical fiber 20C is inserted into the insertion hole H10 at four rotation angles. The optical fiber 20C is inserted and fixed to the ferrule 10C at an angle with good transmission efficiency among the four rotation angles.

In the optical transducer 1D of the modification 4 shown in FIG. 12, the insertion hole H10 of the ferrule 10D is a square (square), the optical fiber 20D is a regular octagon, and has eight outer planes. The inner shape of the insertion hole H10 is set in a state in which the notched optical fiber 20D is fitted.

In the optical transducer 1D, the optical fiber 20D is inserted into the insertion hole H10 at six rotation angles. The optical fiber 20D is inserted and fixed to the ferrule 10D at an angle with high transmission efficiency among the eight rotation angles.

The insertion hole H10 and the optical fiber 20D are in a fitted state, but there are spaces at the four corners (square corners) of the insertion hole H10. When the optical fiber 20D is inserted after the transparent adhesive 19 is injected into the insertion hole H10, the excess adhesive 19 flows into the space even if the amount of the adhesive 19 is excessive. From this point of view, the optical transducer 1D is easy to manufacture.

In the optical transducer 1E of the modified example 5 shown in FIG. 13, the insertion hole H10 of the ferrule 10E is a regular triangle, the optical fiber 20E is a regular hexagon, and has six outer planes. The inner shape of the insertion hole H10 is set in a state in which the notched optical fiber 20E is fitted.

In the optical transducer 1E, the optical fiber 20E is inserted into the insertion hole H10 at six rotation angles. The optical fiber 20E is inserted and fixed to the ferrule 10E at an angle with good transmission efficiency among the six rotation angles.

In the optical transducer 1E, there are wider spaces than the optical transducer 1D at the three corners of the insertion hole H10 (corners of an equilateral triangle).

The cross-sectional shape of the insertion hole H10 in the direction orthogonal to the optical axis is a regular N polygon (N is an integer of 3 or more) and has N inner planes, and the cross-sectional shape of the optical fiber in the orthogonal direction to the optical axis is a regular M polygon. In an optical transducer with M and M outer planes, there are N or M rotation angles of the optical fiber 20 (where M = 2N or N = 2M). The number of rotation angles is not limited to M = 2N and N = 2M, and may be M = 4, N = 16 or M = 3 and N = 12, for example.

The larger the number of rotation angles that can be selected, the more the optical transducer with high transmission efficiency can be manufactured. However, if the number of inner planes (outer planes) increases, it becomes difficult to keep the optical fiber 20 in a non-rotating state. Therefore, the number of rotation angles, for example, the number N of inner planes of the insertion hole H10 is preferably 8 or less.

<Modification 6>
In the optical transducer 1F of the modification 6 shown in FIG. 14, the core 21 of the optical fiber 20F is eccentric with respect to the clad 22. That is, the center C21 of the core 21 is largely separated from the center C20 of the optical fiber 20 (clad 22).

In the optical transducer 1F, the eccentric state of the core 21 is evaluated. For example, the tip end surface of the optical fiber 20F is observed with a microscope, or the distribution of light that enters from one end and exits from the other end is measured.

A notch is formed according to the eccentric state of the core 21. That is, the outer plane 20SS is formed at a position (optimal position) centered on a point where the straight line L passing through the center C21 of the core 21 and the center C20 of the optical fiber 20 intersects with the coating layer 23. That is, when the optical fiber 20 is inserted into the insertion hole H10 of the ferrule 10, the center C21 of the core 21 is closer to the center of the insertion hole H10 than when the outer flat surface 20SS is formed at another position. In addition, the outer flat surface 20SS is formed.

For example, when the center C21 of the core 21 is decentered from the center C20 of the optical fiber 20 by 3 μm, the outer plane 20SS where the cladding 22 is exposed is formed by completely notching the coating layer 23 having a thickness of 7.5 μm. The center C20 of the fiber 20 moves 3.75 μm. Therefore, when the optical fiber 20 is inserted into the insertion hole H10 of the ferrule 10, the center C21 of the core 21 is close to the center C10 of the insertion hole H10.

The present invention is not limited to the above-described embodiments and modifications, and various modifications, combinations and applications are possible without departing from the spirit of the invention.

1, 1A to 1F ... Optical transducer for endoscope 2 ... Imaging unit 3 ... Insertion unit 6 ... Endoscopy system 8 ... Optical module 9 ... Endscope 10 ... -Ferrule 10SA ... 1st main surface 10SB ... 2nd main surface 10SS ... Inner plane 15 ... Wiring board 15SA ... Mounting surface 15SB ... Rear surface 19 ... Adhesive 20・・・ Optical fiber 20M ・・・ Conductor 20SS ・・・ Outer plane 21 ・・・ Core 22 ・・・ Clad 23 ・・・ Cover layer 30 ・・・ Optical element 30SA ・・・ Light emitting surface 30SS ・・・ Outer plane 31 ... Light emitting part 32 ... External electrode 40 ... Imaging element 41 ... Cover glass 42 ... Three-dimensional wiring board 50 ... Lens unit H10 ... Insertion hole H10A ... First hole H10B ... Second hole

Claims

A ferrule having a first main surface and a second main surface facing the first main surface, the ferrule having an insertion hole penetrating from the first main surface to the second main surface;
An optical element having a light emitting portion for generating an optical signal, wherein the light emitting portion is arranged at a position facing the insertion hole,
An optical fiber for transmitting the optical signal, which includes a core, a clad, and a coating layer, and a tip portion of which is fitted into the insertion hole in a non-rotating state.
At least one outer plane on the side surface of the tip of the optical fiber,
The inner surface of the insertion hole has at least one inner plane,
An optical transducer for an endoscope, wherein the outer plane and the inner plane are in contact with each other.
A plurality of outer planes on the side surface,
There are a plurality of inner planes on the inner surface,
The optical transducer for an endoscope according to claim 1, wherein each of the plurality of outer planes is in contact with each of the plurality of inner planes that face each other.
The optical transducer for an endoscope according to claim 1 or 2, wherein the outer plane is a cutout surface of the coating layer.
The cross-sectional shape of the insertion hole in the direction orthogonal to the optical axis is a regular N-gonal shape (N is an integer of 3 or more) having N inner planes,
4. The endoscope according to claim 2, wherein there are M (M = 2N or N = 2M) outer planes on the side surface of the optical fiber. Optical transducer.
The insertion hole has a first hole that has the inner plane and has an opening on the first main surface, and a second hole that is connected to the first hole and does not have the inner plane. It consists of a second hole with an opening,
The said tip part of the said optical fiber is fitted with the said 2nd hole, and is not fitted with the said 1st hole, The any one of Claim 1 to 4 characterized by the above-mentioned. Optical transducer for endoscope.
The optical fiber, the core is eccentric to the clad,
The endoscope according to claim 1, wherein the outer plane is formed at a position where the center of the core of the optical fiber inserted into the insertion hole is close to the center of the insertion hole. Optical transducer.
An endoscope including the optical transducer for an endoscope according to any one of claims 1 to 6.
A light emitting element having a light emitting portion for generating an optical signal on a light emitting surface,
A ferrule having a first main surface and a second main surface facing the first main surface, the ferrule having an insertion hole penetrating from the first main surface to the second main surface;
An optical fiber having a core, a clad, and a coating layer, the insertion hole having an inner flat surface on the inner surface, and the tip having an outer flat surface on the side surface are fitted to each other, and transmitting the optical signal. A method of manufacturing an optical transducer for an endoscope, comprising:
An inserting step of inserting and fitting the tip portion into the insertion hole,
Generating the optical signal from the light emitting unit, a measuring step of measuring the light amount of the optical signal transmitted by the optical fiber,
A withdrawing step of withdrawing the optical fiber from the insertion hole,
A rotation step of rotating the optical fiber about an optical axis,
The insertion step, the measuring step, the removing step, and the rotating step are repeatedly performed, and an optimum angle selecting step of selecting an optimum angle that is the rotation angle at which the light amount is the largest,
A reinsertion step of inserting the optical fiber into the insertion hole at the optimum angle,
A step of fixing the optical fiber to the ferrule, and a method for manufacturing an optical transducer for an endoscope, comprising:
The insertion hole has a first hole that has the inner plane and has an opening on the first main surface, and a second hole that is connected to the first hole and does not have the inner plane. It consists of a second hole with an opening,
In the inserting step, the tip portion is fitted with the second hole,
In the removing step, the tip portion is removed from the second hole, but is not removed from the first hole,
The method of manufacturing an optical transducer for an endoscope according to claim 8, wherein, in the rotating step, the tip portion is not inserted into the second hole, but is inserted into the first hole. ..