JPH0593820A - Coupling structure between optical waveguide and optical fiber - Google Patents

Abstract

(57) [Summary] [Object] Regarding a coupling structure of an optical waveguide and an optical fiber, an object thereof is to provide a coupling structure of the optical waveguide and the optical fiber having a small optical coupling loss. In an optical device in which an end face of an optical fiber 1 is brought into contact with an end face of an optical waveguide 5 formed on an optical circuit board 20 to optically couple the optical fiber 1 and the optical waveguide 5, the optical device is placed at a position decentered from a desired position. An eccentric hole 31 is bored, and a columnar body 30 in which the end of the optical fiber 1 is inserted into the eccentric hole 31 and a guide portion 41 for holding the columnar body 30 rotatably adjustable are provided at positions facing the optical waveguide 5. A fiber holding base 40, and a base 21 on which the fiber holding base 40 and the optical circuit board 20 are mounted so as to face each other on the upper surface, and the fiber holding base 40 is a base after the movement and adjustment on the base 21. The columnar body 30 is fixed to the fiber holding base 40 after the end face of the columnar body 30 is brought into contact with the end face of the optical circuit board 20 to adjust the rotation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coupling structure for an optical waveguide and an optical fiber. With the progress of semiconductor technology, an optical device is provided in which optical waveguides are arranged in parallel on an optical circuit board, and optical elements such as light emitting elements and light receiving elements arranged on the optical circuit board are optically coupled to the respective optical waveguides. Has been done.

There is also provided an optical device in which a plurality of optical waveguides are provided on an optical circuit board as desired to form an optical coupler.
For this reason, there is a demand for a coupling structure between the optical waveguide and the optical fiber, which connects the optical waveguide and the optical fiber of these optical devices with a high degree of coupling.

[0003]

2. Description of the Related Art FIG. 4 is a perspective view of a conventional example, and FIG. 5 is a perspective view of another conventional example. In FIG. 4, reference numeral 10-1 is an optical circuit board in which silica glass is deposited on the surface of a base 11-1 made of silicon or the like, and a narrow optical waveguide 5 and the optical circuit board 5 are provided on the surface. Optical waveguides 6-1 and 6-2 formed by bifurcating at approximately the center of 10-1 are provided.

These optical waveguides are partially striped by photolithography by providing a highly accurate mask on the surface of the optical circuit board 10-1 and injecting ions through strip-shaped windows parallel to the mask. It is formed by increasing the refractive index.

The depths of the optical waveguide 5 and the optical waveguides 6-1 and 6-2 are
Is approximately equal to the diameter of the core of a single-mode optical fiber
It is about 10 μm, and its width is almost equal to the diameter of the core.
The optical circuit board 10 is provided with concave grooves 16-1 on the extension line of the optical waveguide 5 and on the extension lines of the optical waveguides 6-1 and 6-2.

It is well known that these concave grooves 16-1 can be formed in a highly precise channel shape by chemical etching or the like by photolithography means. Then, the optical fiber 1 is inserted into the groove 16-1 of the optical waveguide 5.
Insert the optical fiber 2-1 into the groove 16-1 of 6-1 and the optical fiber 2-2 into the groove 16-1 of optical waveguide 6-2, and contact the end face of the optical fiber with the end face of the optical waveguide. After that, the optical fibers 1, 2-1 and 2-2 are fixed to the optical circuit board 10-1 by using an adhesive 9 such as an ultraviolet curable adhesive.

Therefore, when an optical signal is transmitted from the optical fiber 1, it advances through the optical waveguide 5 and is branched into an optical waveguide 6-1 and an optical waveguide 6-2. Then, the optical fibers 2-1 and 2-2 facing each other are optically coupled and transmitted.

In FIG. 5, 10-2 is an optical circuit board made of, for example, lithium niobate, which is fixed to the upper surface of a square plate-shaped base 11-2 such as a stainless steel plate using an adhesive. .. On the surface of the optical circuit board 10-2, a plurality of narrow optical waveguides 5-
1,5-2,5-3 are formed in parallel at equal pitch. These optical waveguides are made by diffusing titanium etc. to increase the optical refractive index.The cross section is approximately equal to the diameter of the core of a single mode optical fiber, about 10 μm, and its width is almost the same as the diameter of the core. equal.

On the surface of the optical circuit board 10-2, optical elements such as light emitting elements and light receiving elements connected to the respective optical waveguides 5-1, 5-2, 5-3 are mounted, or Integrated circuits, etc. are mounted.

Reference numeral 15 denotes a rectangular parallelepiped fiber holder made of, for example, silicon and has a thickness of the optical circuit board 10-2.
Is approximately equal to the plate thickness. On the surface of the fiber holding table 15, at a pitch equal to the parallel pitch of the optical waveguides 5-1, 5-2, and 5-3, V
The grooves 16-2 are provided in parallel so as to correspond to the optical waveguide. This V
The groove 16-2 is formed by chemical etching using photolithography means.

After applying an adhesive such as epoxy resin to the inner wall of each V-groove 16-2, the optical fibers 1-1,1-
The optical fibers are fixed to these V-grooves 16-2 by inserting the respective end portions of 2, 1-3.

The end face of the optical fiber and the end face of the fiber holder 15 are made to coincide with each other by precision polishing or the like. The end face of the fiber holder 15 formed as described above is closely attached to the end face of the optical circuit board 10-2, and the end face of the optical fiber 1-1 is set to the end face of the optical waveguide 5-1 and the end face of the optical fiber 1-2 is set to the end face. Optical waveguide 5-2
With the end face of the optical fiber 1-3 aligned with the end face of the optical waveguide 5-3, the bottom face of the fiber holding base 15 is bonded to the base 11-2.

Therefore, an optical signal is exchanged between the optical waveguide and the optical fiber.

[0014]

By the way, the former, that is, the one in which the optical circuit board is provided with a concave groove and the optical fiber is inserted into this concave groove, has a thickness of the deposited glass (a thickness of the optical circuit board).
And the etching depth of the groove varies. Therefore, the axis of the optical fiber and the axis of the optical waveguide often do not coincide with each other in the height direction, resulting in a relatively large optical coupling loss.

On the other hand, the latter, that is, the one in which the optical fiber is fixed to the fiber holding base, has a pitch error between the parallel pitch of the optical waveguide and the parallel pitch of the V-grooves arranged on the fiber holding base, and each of them is formed on the fiber holding base. There are variations in the height of the V groove.

Therefore, even if the fiber holder is finely moved in the left-right direction to adjust the position of the optical fiber in the Y-axis direction, the position in the Z-axis direction (height direction) cannot be adjusted, and the axis of the optical waveguide cannot be adjusted. The heights of the core and the axis of the optical fiber do not match. Therefore, there is a problem that the optical coupling loss is large.

The present invention has been made in view of the above points, and an object thereof is to provide a coupling structure for an optical waveguide and an optical fiber having a small optical coupling loss.

[0018]

In order to achieve the above object, the present invention, as shown in FIG. 1, abuts the end face of an optical fiber 1 on the end face of an optical waveguide 5 formed on an optical circuit board 20. In the optical device for optically coupling the optical fiber 1 and the optical waveguide 5, the eccentric hole 31 is bored at a position off the center, and the optical fiber 1 is inserted into the eccentric hole 31.
And a fiber holding base 40 having a guide portion 41 that holds the columnar body 30 in a rotationally adjustable manner at a position facing the optical waveguide 5.
And a base 21 on which the fiber holding base 40 and the optical circuit board 20 are mounted so as to face each other, and the fiber holding base 40 is a base.
After adjusting the movement on the 21 and fixed to the base 21, the cylindrical body 30,
After the end face is in contact with the end face of the optical circuit board 20, the rotation is adjusted, and then the end face is fixed to the fiber holder 40.

Further, as illustrated in FIG. 2, the materials of the columnar body and the fiber holding base are metal materials, and the guide portion is the through hole 51. Then, the fiber holding table 50 is attached to the base 21-1.
It is configured such that the cylindrical body 30 is laser-welded to the fiber holding base 50 by laser welding.

Alternatively, as illustrated in FIG. 3, the material of the cylindrical body and the fiber holding base is ceramics or silicon, and the guide portion is the guide groove 61. Then, fix the fiber holding base 60 to the base 21-2 with an ultraviolet curable adhesive,
The columnar body 70 is fixed to the fiber holding base 60 with an ultraviolet curing adhesive.

[0021]

According to the present invention, the optical fiber is inserted into the eccentric hole of the cylindrical body which is formed at a position deviated from the center, and the cylindrical body can be rotated within the guide portion of the fiber holding base.

Therefore, while rotating the cylindrical body,
By moving the fiber holding base in the left-right direction, the center of the optical fiber moves to a desired position within a circle having the deviation amount of the eccentric hole as a radius.

That is, since the axis of the optical fiber can be aligned with the axis of the optical waveguide, the optical coupling efficiency between the optical fiber and the optical waveguide is high.

[0024]

The present invention will be described in detail with reference to the drawings. The same reference numerals denote the same objects throughout the drawings.

FIG. 1 is a diagram showing the principle of the present invention, FIG. 2 is a perspective view of an embodiment of the present invention, and FIG. 3 is a perspective view of another embodiment of the present invention. In FIG. 1, reference numeral 20 denotes an optical circuit board made of, for example, lithium niobate, which is fixed to the upper surface of a square plate-shaped base 21 made of a stainless steel plate or the like with an adhesive.

An optical waveguide 5 is formed on the surface of the optical circuit board 20. This optical waveguide 5 is made by diffusing titanium or the like to increase the optical refractive index, and its cross section is approximately equal to the diameter of the core of a single mode optical fiber, about 10 μm, and its width is also approximately the diameter of the core. equal.

Reference numeral 30 denotes a cylindrical body having a diameter of about 2 mm and made of, for example, stainless steel, and has a desired amount (eg,
An eccentric hole 31 parallel to the axial center is bored at a position displaced by 10 μm), and the optical fiber 1 (outer diameter is about 125 μ) is inserted into the eccentric hole 31 and fixed by using an adhesive or the like.

After the optical fiber 1 is inserted into the columnar body 30, the end face thereof is polished so that the end face of the optical fiber 1 and the end face of the columnar body 30 are flush with each other.
Reference numeral 40 denotes a horizontally long rectangular parallelepiped fiber holding base made of, for example, stainless steel, etc., and a guide portion 41 is provided at the center thereof. The guide portion 41 shown in the figure is a square groove formed by laser processing or the like with an upper opening, and its groove width is slightly larger than the outer diameter of the columnar body 30.

After the cylindrical body 30 is placed horizontally and inserted into the guide portion 41 of the fiber holding base 40, the fiber holding base 40 is mounted on the base 21.
The optical fiber substrate 40 is placed in contact with the end face of the optical circuit board 20, the fiber holder 40 is finely moved and adjusted in the left-right direction, and the columnar body 30 is rotationally adjusted so that the axis of the optical fiber 1 becomes the optical waveguide. 5, the fiber holder 40 is laser-welded to the base 21, and the cylindrical body 30 is attached to the fiber holder 40.
It is laser welded to and fixed to.

As described above, both end faces are abutted and fixed to each other in a state where the axis of the optical fiber and the axis of the optical waveguide coincide with each other, so that the optical signal can be transmitted and received between the optical waveguide and the optical fiber. Performed and its optical coupling is high.

The alignment of the axes of both the optical fibers is such that when the light emitting element is optically coupled to the optical waveguide 5, the optical fiber 1
Is connected to an optical power meter, and the holding base 40 is finely moved and adjusted in the left-right direction and the columnar body 30 is rotationally adjusted so that the pointer of the optical power meter is maximized.

When a light receiving element is optically coupled to the optical waveguide 5, light is transmitted from the optical fiber 1 and the output of the light receiving element is monitored so that the indicated value becomes maximum.
The holder 40 is finely moved and adjusted in the left-right direction, and the columnar body 30 is rotationally adjusted.

In FIG. 2, 20-1 is an optical circuit board in which silica glass is deposited on the surface of a silicon substrate, and two parallel optical waveguides 5-1 and 5-2 are formed on the surface. The optical waveguides 5-1 and 5-2 are integrated into an optical waveguide 6 at almost the center of the optical circuit board 20-1.

Further, in parallel with this optical waveguide 5-2, another third
The optical waveguide 5-3 is provided and its end is parallel to the optical waveguide 6 in the vicinity thereof. Therefore, the end faces of the optical waveguides 5-1, 5-2, and 5-3 are formed in parallel on one end face of the optical circuit board 20-1 and the end face of the optical waveguide 6 is formed on the other end face. Has been formed. Note that these optical waveguides are partially refracted in a strip shape by providing a highly accurate mask on the surface of the optical circuit board 20-1 by photolithography means and injecting ions through strip-shaped windows parallel to the mask. It is formed by increasing the rate.

Therefore, when an optical signal is transmitted to the optical waveguide 6, the light having a wavelength of 1.3 μm goes straight and branches to the optical waveguides 5-1 and 5-2 to proceed to the terminal of the optical circuit board 20-1. move on. Further, light having a wavelength of 1.55 μm travels to the optical waveguide 5-3 and travels to the terminal of the optical circuit board 20-1.

Reference numeral 21-1 is a base on a rectangular plate which is larger than the optical circuit board 20-1 made of a stainless steel plate, and is an optical circuit board.
20-1 is fixed to the center of the upper surface of the base 21-1 using an adhesive.

Reference numeral 30 denotes a cylindrical body having a diameter of about 2 mm and made of, for example, stainless steel or the like, and has a desired amount (eg,
An eccentric hole 31 parallel to the axis is bored at a position displaced by 10 μm), and the optical fiber 2 (outer diameter is about 125 μ) is inserted into the eccentric hole 31 and fixed with an adhesive or the like.

Further, after inserting the optical fibers 1-1, 1-2, 1-3 into the eccentric holes 31 of the other three cylindrical bodies 30, and polishing the end faces of the optical fibers 1-1, 1-2, 1-3, the optical fibers End face and cylinder 30
Is finished so that it is flush with the end surface of.

Reference numeral 50-1 is a fiber holder made of stainless steel, which is convex in a front view and is installed on the end face side of the optical waveguide 6 of the optical circuit board 20-1. A through hole 51 into which the cylindrical body 30 fits properly is formed in the center of the fiber holding base 50-1 by horizontal laser processing or the like.

On the other hand, reference numeral 50-2 is a fiber holding base which is made of stainless steel and has a convex shape in a front view and which is installed on the end face side of the optical waveguides 5-1, 5-2, 5-3 of the optical circuit board 20-1. is there. Fiber holder
In the 50-2, three through holes 51 into which the cylindrical body 30 fits properly are arranged at a pitch equal to the parallel pitch of the optical waveguides 5-1, 5-2 and 5-3.
Perforated horizontally.

Then, the cylindrical body 30 into which the optical fiber 2 is inserted is attached.
After inserting the fiber holder 50-1 into the through hole 51 of the fiber holder 50-1, the fiber holder 50-1 is placed on the base 21-1, and its end face is brought into contact with the end face of the optical circuit board 20-1 on the optical waveguide 6 side. In contact with each other, the fiber holding base 50-1 is finely moved and adjusted in the left-right direction, and the cylindrical body 30 is rotationally adjusted so that the axis of the optical fiber 2 is aligned with the optical waveguide 6.
Align the fiber holder 50-1 with the base 21
-1 is laser-welded (shown by a black dot), and the cylindrical body 30 is laser-welded (shown by a black dot) to the fiber holding base 50-1 and fixed.

On the other hand, the optical waveguide 5-1 of the fiber holder 50-2
Cylindrical body with optical fiber 1-1 inserted in through hole 51 facing to
30 into the through-hole 51 facing the optical waveguide 5-2 to the optical fiber 1-
The cylindrical body 30 having the optical fiber 1-3 inserted therein is inserted into the through hole 51 facing the optical waveguide 5-3.

Then, the fiber holding base 50-2 is placed on the base 21-1, and its end face is the optical waveguides 5-1, 5-2, 5-of the optical circuit board 20-1.
The fiber holding table 50-2 is finely moved in the left-right direction by finely moving it while making contact with the end face on the 3 side, and the respective cylindrical bodies 30 are rotationally adjusted so that the axis of the optical fiber 1-1 becomes the optical waveguide 5-. To the axis of 1, the axis of the optical fiber 1-2 to the axis of the optical waveguide 5-2,
Align the axis of the optical fiber 1-3 with the axis of the optical waveguide 5-3, and then laser-weld the fiber holder 50-2 to the base 21-1 (indicated by the black dots) to form each cylinder. The 30 is fixed to the fiber holding base 50-2 by laser welding (shown by a black dot).

In the adjustment order described above, first, a light emitting element such as a semiconductor laser is connected to the optical fiber 2, and each of the other optical fibers 1-1, 1-2, 1-3 is connected to an optical power meter. Then, after temporarily fixing the fiber holding base 50-2 to the end face of the optical circuit board 20-1, the fiber holding base 50- is connected so that the pointer of the optical power meter connected to the optical fiber 1-1 becomes maximum. While finely adjusting 1 in the left and right direction,
The columnar body 30 is rotationally adjusted to first fix the fiber holding base 50-1 side.

Next, the fiber holding base 50-2 side is adjusted. At this time, the main optical fiber, in the embodiment, the optical fiber 1-1 is aligned first. That is, the fiber holding base 50-2 is finely moved and adjusted in the horizontal direction so that the pointer of the optical power meter connected to the optical fiber 1-1 is maximized, and the cylindrical body 30 is rotationally adjusted to hold the fiber. The base 50-2 is fixed to the base 21-1, and the cylindrical body 30 in which the optical fiber 1-1 is inserted is fixed to the fiber holding base 50-2.

Next, the fiber optical fiber is connected so that the pointer of the optical power meter connected to the optical fiber 1-2 becomes maximum.
Rotate the cylindrical body 30 with 1-2 attached as desired to
Fix 30 to holding table 50-2. Then, similarly, the columnar body 30 on the optical fiber 1-3 side is fixed.

Since the adjustment order is as described above,
The axis of the optical fiber 1-1 and the axis of the optical waveguide 5-1 coincide with each other with high accuracy, but the other optical fibers 1-2 and 1-3 correspond to the corresponding optical waveguides 5-2 and 5-. A slight discrepancy in the axes is inevitable with 3.

As described above, since the fiber holding base, the cylindrical body and the base are made of metal respectively, they can be fixed by the laser welding means, and the cylindrical body can be easily and without being displaced. There is an advantage that the fiber holding base can be fixed to the holding base respectively.

In FIG. 3, reference numeral 20-2 is an optical circuit board made of, for example, lithium niobate, which is fixed to the upper surface of a ceramic base 21-2 made of, for example, zirconia using an adhesive.

On the surface of the optical circuit board 20-2, a plurality of narrow optical waveguides 5-1, 5-2, 5-3 are formed in parallel at equal pitches. These optical waveguides are made by diffusing titanium etc. to increase the optical refractive index.The cross section is approximately equal to the diameter of the core of a single mode optical fiber, about 10 μm, and its width is almost the same as the diameter of the core. equal.

Reference numeral 60 denotes a rectangular parallelepiped fiber holder made of silicon or the like. Then, on the surface of the fiber holding base 60, guide grooves (V grooves) 61 are provided in parallel at a pitch equal to the parallel pitch of the optical waveguides 5-1, 5-2, 5-3 corresponding to the optical waveguides. is there.

The guide groove 61 is formed by chemical etching using photolithography means.
70 is made of ceramics such as zirconia and has a diameter of 2
It is a cylindrical body of about mm, and the desired amount from the center (for example, 10μ
m) Drill an eccentric hole 71 parallel to the axis at the displaced position,
Insert an optical fiber (outer diameter is about 125 μ) into this eccentric hole 71, fix it with an adhesive or the like, and polish its end face,
The end face of the optical fiber and the end face of the cylindrical body 70 are finished to be flush with each other.

The number of cylindrical bodies 70 is equal to the number of optical waveguides,
In the figure, there are three, and the cylindrical body 70 inserted into the guide groove 61 corresponding to the optical waveguide 5-1 has the optical fiber 1-1 inserted into the guide groove 61 corresponding to the optical waveguide 5-2. The optical fiber 1-2 is attached to the optical fiber 1-3, and the optical fiber 1-3 is attached to the cylindrical body 70 to be inserted into the guide groove 61 corresponding to the optical waveguide 5-3.

Then, the fiber holding base 60 is placed on the base 21-2, the end face of the fiber holding base 60 is brought into contact with the end face of the optical circuit board 20-2, and the fiber holding base 60 is finely moved and adjusted in the left-right direction.
Adjust the rotation of each cylinder 70 so that the axis of the optical fiber 1-1 is the axis of the optical waveguide 5-1 and the axis of the optical fiber 1-2 is the axis of the optical waveguide 5-2. Align the axis of the optical fiber 1-3 with the axis of the optical waveguide 5-3, and then fix the fiber holding base 60 to the base 21-2 using an ultraviolet curing adhesive, and fix each cylindrical body. 70 is fixed to the fiber holding base 60 using an ultraviolet curing adhesive.

By using silicon for the fiber holder as described above, the guide groove (V groove) can be formed by photolithography, and the shape of the obtained V groove and its parallel pitch are highly accurate. There are advantages.

The ultraviolet-curable adhesive is easily cured by irradiating it with ultraviolet rays for about one minute. Therefore,
Compared to other epoxy resin adhesives having a long curing time, for example, there is an advantage that the columnar body and the fiber holder are not displaced during the curing of the adhesive.

In the case where a plurality of guide grooves are provided on one fiber holding base as described above, first, the optical fiber at the central portion is adjusted so that the cylindrical body and the fiber holding base serve as the base holding base. It is preferable that the optical fibers are fixed to each other and then the cylindrical bodies arranged on the left and right are rotationally adjusted to adjust the respective optical fibers.

By adopting such an adjustment order, the cumulative arrangement pitch error of the guide grooves can be reduced. In order to align the axes of all the optical fibers with the corresponding optical waveguides with extremely high accuracy, the fiber holder 60 should be divided into fiber holders having a single guide groove as shown in FIG. To do.

[0059]

As described above, according to the present invention, an eccentric hole is bored at a position deviated from the center as desired, and a cylindrical body having an optical fiber inserted in the eccentric hole is rotated within the guide portion of the fiber holding base. It is a coupling structure of an optical waveguide and an optical fiber configured to be movable, and the axis of the optical fiber can be aligned with the axis of the optical waveguide with high accuracy, and the optical coupling efficiency between the optical fiber and the optical waveguide is high. It has a practically excellent effect of being high.

Further, when applied to an optical fiber array and an optical waveguide array, the adjustment work is relatively easy, and the optical coupling efficiency between each optical fiber and the optical waveguide is relatively high.

[Brief description of drawings]

FIG. 1 is a diagram showing the principle of the present invention.

FIG. 2 is a perspective view of an embodiment of the present invention.

FIG. 3 is a perspective view of another embodiment of the present invention.

FIG. 4 is a perspective view of a conventional example.

FIG. 5 is a perspective view of another conventional example.

[Explanation of symbols] 1,1-1,1-2,1-3,2,2-1,2-2 optical fiber 5, 5-1,5-2,5-3,6,6-1, 6-2 Optical waveguide 10-1,10-2,20,20-1,20-2 Optical circuit board 11-1,11-2,21,21-1,21-2 Base 15,40,50- 1,50-2,60 Fiber holder 16-1 Groove 16-2 V-groove 30,70 Cylinder 31,71 Eccentric hole 41 Guide part 51 Through hole 61 Guide groove

Claims (2)

[Claims] 1. The end face of the optical fiber (1) is provided with an optical circuit board (20).
In an optical device that abuts on the end face of the optical waveguide (5) formed on the optical fiber to optically couple the optical fiber (1) and the optical waveguide (5), the eccentric hole (31) is located at a position off the center as desired. A cylindrical body (3 with the end of the optical fiber (1) inserted into the eccentric hole (31).
0), and a guide portion (41) for holding the columnar body (30) in a rotationally adjustable manner.
A fiber holder (40) at a position facing the optical waveguide (5), and a base (on which the fiber holder (40) and the optical circuit board (20) are mounted so as to face the upper surface ( 21), the fiber holding base (40) is fixed to the base (21) after being moved and adjusted on the base (21), the cylindrical body (30), A coupling structure for an optical waveguide and an optical fiber, characterized in that the end face is brought into contact with the end face of the optical circuit board (20) to be rotationally adjusted, and then fixed to the fiber holding base (40). 2. The cylindrical body and the fiber holding base according to claim 1, each of which is made of metal, the guide portion is a through hole (51), and the fiber holding base (50) is on a base (21-1), A coupling structure for an optical waveguide and an optical fiber, wherein the columnar body (30) is laser-welded to the fiber holding base (50), respectively. 3. The cylindrical body and the fiber holding base according to claim 1, each of which is made of ceramic or silicon, the guide portion is a guide groove (61), and the fiber holding base (60) is a base (21-2). In addition, a coupling structure for an optical waveguide and an optical fiber, characterized in that the columnar body (70) is fixed to the fiber holding base (60) with an ultraviolet curing adhesive.