JP2002062454A - Optical waveguide connecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connecting structure for an optical waveguide, a structure reducing deviation of an optical axis and dispersing with formation of a terrace. SOLUTION: The device is equipped with a plurality of optical waveguide base plates 10, 20 on which optical waveguides 12, 22 are formed and with a holding plate 30 on which the base plates 10, 20 are held. Since the optical waveguide base plates 10, 20 are held by the holding plate 30, it is possible to adjust the height of the optical waveguides 10, 20 and to eliminate the need of providing a terrace for the base plates 10. 20 themselves.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to connection of optical waveguides.

[0002]

2. Description of the Related Art Connecting optical waveguides has been conventionally performed. At the time of connection, it has also been conventionally performed to reduce the loss of light transmitted through the optical waveguide caused by the connection. An example of such a connection method will be described with reference to FIG.

FIG. 21 is a sectional view of a connection portion of an optical waveguide. The optical waveguides 102 and 112 are
110. On the optical waveguides 102 and 112, yats 104 and 114 are mounted. Light enters the optical waveguide 102 from a light source 130 via a lens 132. Light passes through the optical waveguide 102 and enters the optical waveguide 112. The light transmitted through the optical waveguide 112 enters the optical power meter 140. The optical power meter 140 measures the power of light.

Here, while moving the optical waveguide substrate 110, a position of the optical waveguide substrate 110 at which the optical power measured by the optical power meter 140 is maximized is searched. Such a search for the position of the optical waveguide substrate 110 is called axis adjustment. The UV curing adhesive 120 is applied to the optical waveguides 102, 112, the optical waveguide substrates 100, 110, and the toys 104, 114 near the portions where the optical waveguides 102, 112 are connected. Therefore, if the position of the optical waveguide substrate 110 at which the optical power measured by the optical output meter 140 is maximized is determined,
Place the optical waveguide substrate 110 at that position, and
The optical waveguide substrate 1 is irradiated with the curing adhesive 120 to be cured.
Fix the position of 10.

There is also a method of connecting an optical waveguide without using a light source or an optical power meter. One example is shown in FIGS.
3 will be described.

FIG. 22 is a front view of a connection portion of the optical waveguide. Referring to FIG. 22A, optical waveguides 202, 30
2 is provided on the optical waveguide substrates 200 and 300. Note that the upper optical waveguide substrate 30 is also provided above the optical waveguide 302.
4 are arranged. The optical waveguide 302 is etched by etching.
In addition, there is a portion where the upper optical waveguide substrate 304 is shaved and only the optical waveguide substrate 300 remains, and the surface of the portion is the terrace 300a. As shown in FIG. 22B, if the optical waveguide substrate 200 is placed on the terrace 300a, the optical waveguide 20
The heights of 2 and 302 match.

FIG. 23 is a plan view of a connection portion of the optical waveguide. As shown in FIG. 23A, two cross-shaped markers 210 are provided beside the optical waveguide 202. As shown in FIG. 23B, a portion where the marker 210 is to be located (the optical waveguides 202 and 302) is located on the terrace 300a.
(A part where the position on the plane is matched) is provided with two markers 310 with a white cross. Marker 210
And the marker 310 combine to look square
This means that the alignment between the marker 210 and the marker 310 has been successful. Therefore, as shown in FIG. 23 (c), the optical waveguide substrate 200 or 300 is moved so that the marker 210 and the marker 310 are combined and look like a square pattern 410, and the optical waveguides 202 and 3 are planarly moved.
02 is performed.

[0008]

However, each of the above two methods has its own problems. In the method described with reference to FIG. 21, positioning accuracy of about 2 μm is required in positioning the optical waveguide substrate 110 in the height and in-plane directions. Therefore, a high-precision optical axis adjustment mechanism is required, and it takes time to adjust the optical axis, resulting in poor productivity. Also,
During the optical axis adjustment, the output of the light source 130 fluctuates,
If the coupling efficiency between the optical waveguide 30 and the optical waveguide 102 fluctuates, the optical axis cannot be adjusted accurately.

If the UV curing adhesive 120 is applied only to the portion where the optical waveguide substrates 100 and 110 are bonded, the area of the bonded portion is reduced, and the mechanical strength of the bonded portion is reduced. Therefore, as shown in FIG.
4, 114 and the lower part of the optical waveguide substrate 100, 110
A hardening adhesive 120 is applied. However, the displacement of the optical axis after curing or due to temperature fluctuation increases due to an increase in the application amount of the UV curing adhesive 120.

[0010] Therefore, it is difficult to minimize the optical axis deviation and to make a connection with high adhesive strength.

The method described with reference to FIGS. 22 and 23 cannot be applied to a substrate on which a terrace cannot be formed by etching, such as a LiNbO ₃ substrate.

Therefore, the present invention reduces the optical axis deviation,
It is an object to provide a connection structure of an optical waveguide which does not require the formation of a terrace.

[0013]

According to a first aspect of the present invention, a plurality of optical waveguide substrates having optical waveguides formed thereon and a holding plate for holding the plurality of optical waveguide substrates are provided. .

According to the optical waveguide connecting device configured as described above, the height of the optical waveguide can be adjusted by holding the plurality of optical waveguide substrates by the holding plate. Moreover, since the holding plate holds the plurality of optical waveguide substrates, it is not necessary to provide a terrace on the optical waveguide substrate itself.

According to a second aspect of the present invention, there are provided a plurality of optical waveguide substrates on which optical waveguides are formed, a holding plate for holding the plurality of optical waveguide substrates, and an optical waveguide substrate positioning marker indicating a position of the optical waveguide substrate. And a holding plate positioning marker that indicates the position of the holding plate and is disposed at a position corresponding to the optical waveguide substrate positioning marker.

According to the optical waveguide connecting device configured as described above, the height of the optical waveguide can be adjusted by holding the plurality of optical waveguide substrates by the holding plate. Further, the planar position of the optical waveguide can be adjusted by the optical waveguide substrate positioning marker and the holding plate positioning marker. Therefore, deviation of the optical axis of the optical waveguide can be reduced. Moreover, since the holding plate holds the plurality of optical waveguide substrates, it is not necessary to provide a terrace on the optical waveguide substrate itself.

A third aspect of the present invention is the invention according to the second aspect, wherein the spacer is disposed between the plurality of optical waveguide substrates and the holding plate, and separates the plurality of optical waveguide substrates from the holding plate. , Is provided.

The invention according to claim 4 is the invention according to claim 3, wherein the marker for positioning the optical waveguide substrate is formed on the surface of the optical waveguide substrate, and the marker for positioning the holding plate is:
Formed on the spacer.

"Forming on a spacer" also includes using the end face of the spacer itself as a marker.

According to a fifth aspect of the present invention, in the third aspect, the holding plate positioning mark is formed on the surface of the holding plate, and the optical waveguide board positioning mark is formed on the spacer. It is configured as follows.

"Forming on a spacer" includes using the end face of the spacer itself as a marker.

The invention according to claim 6 is the invention according to claim 3, wherein the spacer is an optical waveguide substrate side spacer attached to the optical waveguide substrate, and a holding plate side spacer attached to the holding plate. And the optical waveguide substrate positioning marker is formed on the optical waveguide substrate-side spacer, and the holding plate positioning marker is formed on the holding plate-side spacer.
It is configured as follows.

"Forming on a spacer" also includes using the end face of the spacer itself as a marker.

According to a seventh aspect of the present invention, there is provided any one of the first to sixth aspects, wherein a fixing means for fixing the optical waveguide substrate and the holding plate is provided. .

The invention according to claim 8 is the invention according to claim 7, wherein the fixing means is a UV-curable adhesive or a thermosetting adhesive.

The ninth aspect of the present invention is the invention according to any one of the third to sixth aspects, wherein the height of the spacer is set so that the optical axes of the plurality of optical waveguides have the same height. Stipulated, configured as follows.

The invention according to claim 10 is the invention according to any one of claims 3 to 6, wherein the height of the spacer is determined so that the optical waveguides connected to each other intersect. And so on.

An eleventh aspect of the present invention is the invention according to any one of the first to sixth aspects, wherein the difference between the thermal expansion coefficient of the holding plate and the thermal expansion coefficient of the optical waveguide substrate is predetermined. Is within the value of.

A twelfth aspect of the present invention is the invention according to any one of the first to sixth aspects, wherein the end face of the optical waveguide is AR-coated.

A thirteenth aspect of the present invention is the invention according to any one of the first to sixth aspects, wherein the end face of the optical waveguide is obliquely inclined with respect to the optical axis. Is done.

The invention according to claim 14 is the invention according to any one of claims 1 to 6, wherein a refractive index matching agent is disposed between the optical waveguides connected to each other.
It is configured as follows.

According to a fifteenth aspect of the present invention, a plurality of optical waveguide substrates on which an optical waveguide and an optical waveguide side metal pad are formed, a plurality of optical waveguide substrates, and a holding plate on which a holding plate side metal pad is formed. And a fixing means for fixing the optical waveguide substrate and the holding plate, formed by melting a solder bump formed on the optical waveguide side metal pad or the holding plate side metal pad. You.

According to the optical waveguide connecting device configured as described above, the height of the optical waveguide can be adjusted by holding the plurality of optical waveguide substrates by the holding plate. Further, the planar position of the optical waveguide can be adjusted by the solder bump. Therefore, deviation of the optical axis of the optical waveguide can be reduced. Moreover, since the holding plate holds the plurality of optical waveguide substrates, it is not necessary to provide a terrace on the optical waveguide substrate itself.

[0034]

Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment First, the configuration of the first embodiment will be described. FIG. 1 is a front view (FIG. 1A) and a plan view (FIG. 1) of an optical waveguide connection device 1 when an optical waveguide according to the first embodiment is connected.
(B)).

Referring to FIG. 1A (front view), optical waveguides 12 and 22 are provided on optical waveguide substrates 10 and 20, respectively. The optical waveguide substrates 10 and 20 may be, for example, substrates formed of a dielectric. For example, it may be a LiNbO ₃ substrate. Optical waveguide 12, 22 are intended to transmit light, such as Ti (the titanium), the optical waveguide substrate 1 is a LiNbO ₃ substrate
It can be made by thermal diffusion to 0 and 20. Here, the optical waveguide substrates 10 and 20 are arranged so that the optical waveguides 12 and 22 face downward, and one ends of the optical waveguides 12 and 22 are close to each other. The holding plate 30 holds the optical waveguide substrates 10 and 20 and is arranged to face the optical waveguides 12 and 22.
The height of the optical waveguides 12 and 22 can be adjusted by the holding plate 30. That is, the spot positions (optical axes) of the end faces of the optical waveguides 12 and 22 which are close to each other can be matched. The material of the holding plate 30 is the optical waveguide substrates 10, 2
It is preferable that the thermal expansion coefficient of the holding plate 30 be equal to the thermal expansion coefficient of 0. This is to reduce the deviation of the optical axis due to a temperature change. However, it may be difficult to make them exactly the same, so that the difference between the thermal expansion coefficient of the optical waveguide substrates 10 and 20 and the thermal expansion coefficient of the holding plate 30 may be within an allowable range.

The optical waveguide substrates 10 and 20 are fixed to the holding plate 30 by adhesives 42 and 44. Adhesive 42,
Reference numeral 44 denotes a position between the optical waveguide substrates 10 and 20 during positioning.
The optical waveguide substrates 10 and 20 are made movable with respect to the holding plate 30, and when the positioning of the optical waveguide substrates 10 and 20 is completed, the optical waveguide substrates 10 and 20 are fixed to the holding plate 30. desirable. As such adhesives 42 and 44, those which are hardened only after applying some action, such as a UV (Ultra Violet) hardening adhesive or a thermosetting adhesive, are preferable. That is, after the positioning is completed, if ultraviolet light is irradiated or heated, the fixing can be performed after the positioning is completed.

The adhesives 42 and 44 are used for the optical waveguide 12,
22 so as not to adhere to the end face of the optical waveguide substrate
And it may be applied to the holding plate 30. For example, FIG.
As shown in (a), it may be applied from a positioning marker 50 described later to the outer periphery of the holding plate 30.

Next, referring to FIG. 1B (plan view),
The positioning marker 50 is obtained by overlapping an optical waveguide substrate positioning marker (described later) provided on the optical waveguide substrates 10 and 20 with a holding plate positioning marker (described later) provided on the holding plate 30. . The positioning marker 50 is shown in FIG.
The optical waveguide substrates 10, 20 and the holding plate 30 are positioned so as to form a square as shown in FIG. Optical waveguide substrate 1 so that positioning mark 50 is square.
By positioning the 0, 20 and the holding plate 30, the planar positions of the optical waveguides 12, 22 can be adjusted.

Next, a method for manufacturing the optical waveguide connection device 1 will be described. FIG. 2 is a front view of the optical waveguide substrates 10 and 20 and the holding plate 30 before connecting the optical waveguides. FIG.
FIG. 3 is a plan view of the optical waveguide substrates 10 and 20 and a holding plate 30 before connecting the optical waveguide.

Referring to FIG. 2A, the optical waveguide substrate 1
The optical waveguides 0 and 20 are arranged so that the optical waveguides 12 and 22 face downward, and one ends of the optical waveguides 12 and 22 are brought close to each other.
Next, referring to FIG. 2B, the holding plate 30 is connected to the optical waveguide 1.
It is arranged facing 2,22. At this time, an adhesive is applied to the optical waveguide substrates 10 and 20 and the holding plate 30 in advance. Then, as shown by the arrow in FIG.
0 and 20 are placed on the holding plate 30. Thereby, the heights of the optical waveguides 12 and 22 can be adjusted.

After adjusting the heights of the optical waveguides 12, 22, the planar positions of the optical waveguides 12, 22 are adjusted. Referring to FIG. 3A, on the surfaces of the optical waveguide substrates 10 and 20 on which the optical waveguides 12 and 22 are provided, markers 14 and 24 for positioning the optical waveguide substrate are provided. The optical waveguide substrate positioning markers 14 and 24 are cross-shaped markers. Also, referring to FIG. 3B, the optical waveguide 1 of the holding plate 30
On the surface facing 2, 22, a marker 3 for holding plate positioning is provided.
4 are provided. The holding plate positioning mark 34 is a mark obtained by removing the cross shape, which is the type of the optical waveguide substrate positioning marks 14 and 24, from a square. Optical waveguide substrate positioning markers 14, 24 and holding plate positioning markers 34
Are arranged with a high accuracy of about 1 μm error.

Therefore, the optical waveguide substrate positioning marker 1
If the alignment marks 4, 24 and the holding plate positioning mark 34 are aligned, as shown in FIG. 1B, the optical waveguide board positioning marks 14, 24 and the holding plate positioning mark 34 are formed.
Are overlapped, and when the optical waveguide substrates 10 and 20 are viewed from above, the positioning mark 50 becomes a square. By aligning the optical waveguide substrate positioning markers 14 and 24 and the holding plate positioning markers 34, the planar positions of the optical waveguides 12 and 22 can be adjusted. Moreover, since the optical waveguide substrate positioning markers 14 and 24 and the holding plate positioning markers 34 are arranged with high precision, the planar positions of the optical waveguides 12 and 22 can be adjusted with high precision.

The planar alignment of the optical waveguides 12 and 22 is performed by moving the optical waveguide substrates 10 and 20 and the holding plate 30 by a positioning device having an image recognition function, not shown, so that the positioning marks 50 are square. It is preferable to carry out the process. Performing position alignment by image recognition in this way is called visual alignment.

After performing the visual alignment, the adhesives 42 and 44 are irradiated with ultraviolet rays,
By heating 2, 44, the optical waveguide substrates 10, 20 and the holding plate 30 are fixed.

According to the first embodiment, the height of the optical waveguides 12, 22 can be adjusted by holding the plurality of optical waveguide substrates 10, 20 by the holding plate 30. Further, a positioning marker 50 in which the optical waveguide substrate positioning markers 14, 24 and the holding plate positioning marker 34 are superimposed.
Are made square so that the optical waveguides 12 and 22
Can be adjusted in planar position. Therefore, the deviation of the optical axes of the optical waveguides 12 and 22 can be reduced to about 1-2 μm.

Moreover, since the holding plate 30 holds the plurality of optical waveguide substrates 10 and 20, there is no need to provide a terrace on the optical waveguide substrates 10 and 20 themselves.

After the positioning of the plurality of optical waveguide substrates 10 and 20 and the holding plate 30 is performed, the adhesives 42 and
4 is irradiated with ultraviolet rays or the adhesives 42 and 44 are heated, so that the plurality of optical waveguide substrates 10 and 20 and the holding plate 3
Since 0 can be fixed, displacement of the optical axis can be prevented.

In the first embodiment, the reflection of light may be suppressed by performing various processings near the end faces of the optical waveguides 12 and 22 which are close to each other.
FIG. 4 shows a modification in which the reflection of light is suppressed.

As shown in FIG. 4A, the optical waveguides 12, 22
AR (anti reflection) coats 12a and 22a may be applied to the end faces close to each other. As shown in FIG. 4B, the end surfaces of the optical waveguides 12 and 22 may be formed as inclined surfaces 12b and 22b by cutting off the end surfaces that are close to each other. Alternatively, as shown in FIG.
The refractive index matching agent 46 between the adjacent end faces of the two 2, 22
May be arranged.

Second Embodiment The second embodiment is different from the first embodiment in that a spacer 60 is provided between the optical waveguide substrates 10 and 20 and the holding plate 30.
70 is different. Hereinafter, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 5 is a front view of the optical waveguide connecting device 1 when the optical waveguide according to the second embodiment is connected (FIG. 5).
(A)) and a plan view (FIG. 5 (b)).

Referring to FIG. 5A (front view), spacer 60 is provided between optical waveguide substrate 10 and holding plate 30, and spacer 70 is provided between optical waveguide substrate 20 and holding plate 30. , Is located. The spacer 60 is provided on the optical waveguide substrate 1.
It may be fixed to 0 or may be fixed to the holding plate 30. The spacer 70 may be fixed to the optical waveguide substrate 20 or may be fixed to the holding plate 30. The spacers 60 and 70 have the same height, and are formed with high precision of about 1 μm by gold vapor deposition or etching.

The adhesives 42 and 44 may be applied to the optical waveguide substrates 10 and 20 and the holding plate 30 so as not to adhere to the end surfaces of the optical waveguides 12 and 22 and the end surfaces of the spacers 60 and 70. For example, it may be applied between the spacers 60, 60 and between the spacers 70, 70.

According to the second embodiment, the same effects as those of the first embodiment can be obtained. As a modification of the second embodiment, the heights of the spacers 60 and 70 are changed,
Different heights are possible. FIG. 6 shows such a modification.

FIG. 6A is a modified example in which the heights of the optical axes of the optical waveguides 12 and 22 are matched with the heights of the spacers 60 and 70 being made non-uniform. In the modified example shown in FIG. 6A, the thickness t1 of the optical waveguide 12 is larger than the thickness t2 of the optical waveguide 22. Therefore, if the heights of the spacers 60 and 70 are all the same, the height of the optical axis of the optical waveguide 12 will be higher than the height of the optical axis of the optical waveguide 22. Therefore, the height of the spacer 60 is set lower than the height of the spacer 70. Therefore, the heights of the optical axes of the optical waveguides 12 and 22 can be adjusted.

FIG. 6B shows a modification in which the height of the spacer 60 is made non-uniform and the optical axis of the optical waveguide 12 and the optical axis of the optical waveguide 22 intersect. In the modification shown in FIG. 6B, the height of the spacer 60 is
It increases monotonically with distance from the camera. Therefore, the end faces of the optical waveguide 12 and the end face of the optical waveguide 22 which are close to each other are not parallel. The end face of the optical waveguide 12 is the optical waveguide 22
It is inclined as compared with the end face. Thus, the optical waveguide 12
The reflection of light can be suppressed by inclining the end surface of the light emitting element.

Third Embodiment The third embodiment is different from the second embodiment in that the end faces of the spacers 60 and 70 are used in place of the holding plate positioning markers 34.

FIG. 7 is a front view (FIG. 7A) and a plan view (FIG. 7B) of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the third embodiment is connected. ).

As shown in FIG. 7A, the front view of the optical waveguide connection device 1 according to the third embodiment is a front view (FIG. 5A) of the optical waveguide connection device 1 according to the second embodiment. ))
Is almost the same as However, the spacers 60 and 70 must be fixed to the holding plate 30.

Referring to FIG. 7B, the optical waveguide connecting device 1 according to the third embodiment has no positioning mark 50. Instead, the end faces of the spacers 60 and 70 facing the optical waveguide substrates 10 and 20 are used instead of the positioning markers of the holding plate 30. Then, the shapes of the optical waveguide substrate positioning markers 14 and 24 are made the same as the end faces of the spacers 60 and 70.

Incidentally, holding plate positioning markers may be provided on the end faces of the spacers 60 and 70 facing the optical waveguide substrates 10 and 20, and the optical waveguide substrate positioning markers 14 and 24 may be provided at positions corresponding to the markers.

Next, a method of manufacturing the optical waveguide connection device 1 will be described. FIG. 8 is a front view of the optical waveguide substrates 10 and 20 and the holding plate 30 before connecting the optical waveguides. FIG.
FIG. 3 is a plan view of the optical waveguide substrates 10 and 20 and a holding plate 30 before connecting the optical waveguide.

Referring to FIG. 8A, optical waveguide substrate 1
The optical waveguides 0 and 20 are arranged so that the optical waveguides 12 and 22 face downward, and one ends of the optical waveguides 12 and 22 are brought close to each other.
Next, referring to FIG. 8B, the holding plate 30 is connected to the optical waveguide 1.
It is arranged facing 2,22. At this time, an adhesive is applied to the optical waveguide substrates 10 and 20 and the holding plate 30 in advance. Then, as shown by the arrow in FIG.
The spacers 60, 7 fixed to the holding plate 30
Put on 0. Thereby, the heights of the optical waveguides 12 and 22 can be adjusted.

After adjusting the heights of the optical waveguides 12 and 22, the planar positions of the optical waveguides 12 and 22 are adjusted. Referring to FIG. 9A, on the surfaces of the optical waveguide substrates 10 and 20 on which the optical waveguides 12 and 22 are provided, markers 14 and 24 for positioning the optical waveguide substrate are provided. The type of the markers 14 and 24 for positioning the optical waveguide substrate is the spacers 60 and 70.
To the end face of Referring to FIG. 9B,
Spacers 60, 70 are fixed to the holding plate 30,
The end surface serves as a positioning marker. The optical waveguide substrate positioning markers 14 and 24 are arranged with a high accuracy of about 1 μm.

Therefore, the optical waveguide substrate positioning marker 1
If the end faces of the spacers 4 and 24 and the spacers 60 and 70 are aligned, the end faces of the optical waveguide substrate positioning markers 14 and 24 and the spacers 60 and 70 completely overlap as shown in FIG. become. By aligning the end faces of the optical waveguide substrate positioning markers 14 and 24 and the spacers 60 and 70, the planar positions of the optical waveguides 12 and 22 can be adjusted. Moreover, since the optical waveguide substrate positioning markers 14 and 24 are arranged with high precision, the planar positions of the optical waveguides 12 and 22 can be adjusted with high precision.

The planar alignment of the optical waveguides 12 and 22 is performed by moving the optical waveguide substrates 10 and 20 and the holding plate 30 by a positioning device (not shown) having an image recognition function. It is preferable to perform this by completely overlapping the end faces of the spacers 14, 24 and the spacers 60, 70. Performing position alignment by image recognition in this way is called visual alignment.

After performing the visual alignment, the adhesives 42 and 44 are irradiated with ultraviolet rays,
By heating 2, 44, the optical waveguide substrates 10, 20 and the holding plate 30 are fixed.

The third embodiment has the same effects as the first embodiment.

Fourth Embodiment The fourth embodiment is different from the third embodiment in that the spacers 60 and 70 are fixed to the optical waveguide substrates 10 and 20.

FIG. 10 is a front view (FIG. 10A) and a plan view (FIG. 10A) of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the fourth embodiment is connected.
(B)).

The front view of the optical waveguide connection device 1 according to the fourth embodiment is, as shown in FIG. 10A, a front view of the optical waveguide connection device 1 according to the third embodiment (FIG. 7).
It is almost the same as (a)). However, the spacers 60, 7
0 must be fixed to the optical waveguide substrates 10 and 20.

Referring to FIG. 10B, the optical waveguide connecting device 1 according to the third embodiment has no positioning mark 50. Instead, the end faces of the spacers 60 and 70 facing the holding plate 30 are used instead of the positioning markers of the optical waveguide substrates 10 and 20. Then, the shape of the holding plate positioning mark 34 is made the same as the end faces of the spacers 60 and 70.

The spacers 60 and 70 may be provided with a marker for positioning the optical waveguide substrate on the end face facing the holding plate 30, and the holding plate positioning mark 34 may be provided at a position corresponding to the mark.

Next, a method of manufacturing the optical waveguide connection device 1 will be described. FIG. 11 is a front view of the optical waveguide substrates 10 and 20 and the holding plate 30 before connecting the optical waveguides. FIG.
FIG. 3 is a plan view of the optical waveguide substrates 10 and 20 and the holding plate 30 before connecting the optical waveguides.

Referring to FIG. 11A, optical waveguide substrate 1
The optical waveguides 0 and 20 are arranged so that the optical waveguides 12 and 22 face downward, and one ends of the optical waveguides 12 and 22 are brought close to each other.
Next, referring to FIG. 11B, the holding plate 30 is arranged to face the optical waveguides 12 and 22. At this time, an adhesive is applied to the optical waveguide substrates 10 and 20 and the holding plate 30 in advance. Then, as shown by the arrows in FIG. 8, the spacers 60 and 70 fixed to the optical waveguide substrates 10 and 20 are abutted on the holding plate 30. Thereby, the heights of the optical waveguides 12 and 22 can be adjusted.

After adjusting the heights of the optical waveguides 12 and 22, the planar positions of the optical waveguides 12 and 22 are adjusted. Referring to FIG. 12A, spacers 6 are provided on the surfaces of optical waveguide substrates 10 and 20 on which optical waveguides 12 and 22 are provided.
The reference numerals 0 and 70 are fixed, and their end surfaces serve as positioning markers. Referring to FIG. 12B, a holding plate positioning mark 34 is provided on the holding plate 30. The type of the holding plate positioning marker 34 is the spacers 60 and 7.
It is aligned with the 0 end face. The end faces of the spacers 60 and 70 serve as positioning marks. It should be noted that the holding plate positioning markers 34 are arranged with a high accuracy of about 1 μm in error.

Therefore, by aligning the end faces of the holding plate positioning mark 34 and the spacers 60 and 70,
As shown in (b), the end faces of the holding plate positioning mark 34 and the spacers 60 and 70 completely overlap to form a square. If the end faces of the holding plate positioning mark 34 and the spacers 60 and 70 are aligned, the optical waveguide 12,
22 are aligned. Moreover, since the holding plate positioning markers 34 are arranged with high precision, the planar positions of the optical waveguides 12 and 22 can be adjusted with high precision.

The planar alignment of the optical waveguides 12 and 22 is performed by moving the optical waveguide substrates 10 and 20 and the holding plate 30 by a positioning device having an image recognition function (not shown). And spacer 6
It is preferable to perform the process by completely overlapping the end faces of 0 and 70. Performing position alignment by image recognition in this way is called visual alignment.

After performing the visual alignment, the adhesives 42 and 44 are irradiated with ultraviolet rays,
By heating 2, 44, the optical waveguide substrates 10, 20 and the holding plate 30 are fixed.

According to the fourth embodiment, the same effects as in the first embodiment can be obtained.

Fifth Embodiment The fifth embodiment is different from the third and fourth embodiments in that the spacers 60 and 70 are divided.

FIG. 13 is a front view (FIG. 13A) and a plan view (FIG. 13A) of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the fifth embodiment is connected.
(B)).

As shown in FIG. 13A, the front view of the optical waveguide connection device 1 according to the fifth embodiment is a front view (FIG. 7) of the optical waveguide connection device 1 according to the third embodiment.
It is almost the same as (a)). However, the spacers 60, 7
0 is divided into optical waveguide substrate side spacers 60b, 70b and holding plate side spacers 60a, 70a. The optical waveguide substrate-side spacers 60b and 70b are fixed to the optical waveguide substrates 10 and 20, respectively. The holding plate side spacers 60 a and 70 a are fixed to the holding plate 30.

Referring to FIG. 13B, the optical waveguide connecting device 1 according to the fifth embodiment has no positioning mark 50. Therefore, the optical waveguide substrate side spacers 60b, 70b and the holding plate side spacer 60a, which face each other,
The end face of 70 a serves as a positioning mark for the optical waveguide substrates 10 and 20 and a positioning mark for the holding plate 30.

The optical waveguide substrate side spacers 60b and 70b and the holding plate side spacers 60a and 70
The optical waveguide substrate positioning markers 14 and 24 and the holding plate positioning markers 34 may be provided on the end surface of a.

Next, a method for manufacturing the optical waveguide connection device 1 will be described. FIG. 14 is a front view of the optical waveguide substrates 10 and 20 and the holding plate 30 before connecting the optical waveguides. FIG.
FIG. 3 is a plan view of the optical waveguide substrates 10 and 20 and the holding plate 30 before connecting the optical waveguides.

Referring to FIG. 14A, optical waveguide substrate 1
The optical waveguides 0 and 20 are arranged so that the optical waveguides 12 and 22 face downward, and one ends of the optical waveguides 12 and 22 are brought close to each other.
Next, referring to FIG. 14B, the holding plate 30 is arranged to face the optical waveguides 12 and 22. At this time, an adhesive is applied to the optical waveguide substrates 10 and 20 and the holding plate 30 in advance. Then, as shown by arrows in FIG. 14, the spacers 60b, 70b on the optical waveguide substrate side and the spacer 60 on the holding plate side.
a and 70a. Thereby, the optical waveguide 1
The height of 2, 22 can be adjusted.

After adjusting the heights of the optical waveguides 12 and 22, the planar positions of the optical waveguides 12 and 22 are adjusted. Referring to FIG. 15A, spacers 60 are provided on the surfaces of optical waveguide substrates 10 and 20 on which optical waveguides 12 and 22 are provided.
b and 70b are fixed, and the end faces thereof serve as markers for positioning the optical waveguide substrate. Referring to FIG. 15B, spacers 60a and 70a are fixed,
The end face serves as a holding plate positioning marker. Note that the planar positions of the spacers are arranged with high accuracy with an error of about 1 μm.

Therefore, if the end faces of the spacers 60a and 70a and the spacers 60b and 70b are aligned, FIG.
As shown in FIG. 3 (b), the end faces of the spacers 60a, 70a and the spacers 60b, 70b completely overlap each other to form a square. If the spacers 60a and 70a and the spacers 60b and 70b are aligned, the optical waveguide 1
2, 22 can be aligned in a planar manner. Moreover, since the spacers 60a and 70a and the spacers 60b and 70b are arranged with high precision, the planar positions of the optical waveguides 12 and 22 can be adjusted with high precision.

The planar alignment of the optical waveguides 12 and 22 is performed by moving the optical waveguide substrates 10 and 20 and the holding plate 30 by a positioning device having an image recognizing function, not shown, so that the spacers 60a and 70a and the spacers are moved. 60
It is preferable that the end faces b and 70b be completely overlapped. Performing position alignment by image recognition in this way is called visual alignment.

After performing the visual alignment, the adhesives 42 and 44 are irradiated with ultraviolet rays,
By heating 2, 44, the optical waveguide substrates 10, 20 and the holding plate 30 are fixed.

The fifth embodiment has the same effect as the first embodiment.

Sixth Embodiment The sixth embodiment is different from the previous embodiments in that the optical waveguides 12 and 22 are aligned by solder bumps.

First, the configuration of the sixth embodiment will be described.
FIG. 16 is a front view (FIG. 16A) and a plan view (FIG. 16B) of the optical waveguide connecting device 1 when the optical waveguide according to the sixth embodiment is connected.

Referring to FIG. 16A (front view), optical waveguide substrates 10 and 20 are provided with solder bumps 80 on holding plate 30.
It is fixed by. The holding plate 30 is provided with the optical waveguide 12,
Adjust the height of 22. Next, FIG. 16B (plan view)
With reference to FIG.
0 is provided along the outer circumference. The solder bumps 80 perform the planar positioning of the optical waveguides 12 and 22.

Next, a method of manufacturing the optical waveguide connection device 1 will be described. FIG. 17 is a front view of the optical waveguide substrates 10 and 20 and the holding plate 30 before connecting the optical waveguides. FIG.
FIG. 3 is a plan view of the optical waveguide substrates 10 and 20 and the holding plate 30 before connecting the optical waveguides.

Referring to FIG. 17A, optical waveguide substrate 1
The optical waveguides 0 and 20 are arranged so that the optical waveguides 12 and 22 face downward, and one ends of the optical waveguides 12 and 22 are brought close to each other.
Next, referring to FIG. 17B, the holding plate 30 is arranged to face the optical waveguides 12 and 22. And FIG.
The optical waveguide substrates 10 and 20 are temporarily placed on the holding plate 30 as indicated by arrows. However, the temporary placement is performed so that the optical waveguide side metal pads 16 and 26 (described later) are in contact with the solder bumps 80. The solder bumps 80 are fixed to the holding plate 30 in FIG. 17, but may be fixed to the optical waveguide substrates 10 and 20. Also,
Each of the solder bumps 80 has the same amount.

Next, referring to FIG. 18 (a), optical waveguide side metal pads 16 and 26 are provided on the surfaces of optical waveguide substrates 10 and 20 provided with optical waveguides 12 and 22, respectively. . Referring to FIG. 18B, a holding plate-side metal pad 36 is provided on a surface of the holding plate 30 facing the optical waveguides 12 and 22. Metal pads 16, 26, 3
6 are about several tens of μm each. In FIG. 18, the solder bumps 80 are omitted. A solder bump 80 is provided on the holding-plate-side metal pad 36.

The optical waveguide substrates 10 and 20 have already been attached to the holding plate 3.
Since the solder bumps 80 are temporarily placed at 0, the solder bumps 80 are melted by heating, and then cooled. Thereby, the optical waveguide substrates 10 and 20 and the holding plate 30 can be aligned by the surface tension. Such alignment is called self-alignment.

According to the sixth embodiment, the height of the optical waveguides 12 and 22 can be adjusted by holding the plurality of optical waveguide substrates 10 and 20 by the holding plate 30. In addition, the optical waveguides 12 and 22 are self-aligned.
Can be adjusted in planar position. Therefore, the deviation of the optical axes of the optical waveguides 12 and 22 can be reduced to about 1-2 μm. In addition, the holding plate 30 has a plurality of optical waveguide substrates 1.
Since 0 and 20 are held, there is no need to provide a terrace on the optical waveguide substrates 10 and 20 themselves.

Seventh Embodiment The case where one optical waveguide is provided on each of the optical waveguide substrates 10 and 20 has been described.
The optical waveguide substrates 10 and 20 may be provided with a plurality of optical waveguides. The seventh embodiment is different from the previous embodiments in that a plurality of optical waveguides are provided on the optical waveguide substrates 10 and 20.

The configuration of the seventh embodiment will be described. FIG.
FIGS. 19A and 19B are a front view (FIG. 19A) and a plan view (FIG. 19B) of the optical waveguide connection device 1 when the optical waveguide according to the seventh embodiment is connected.

There are a plurality of optical waveguides 12, 22, and the optical waveguides 12 and the optical waveguides 22 are arranged in parallel. In FIG. 19, the optical waveguides 12, 2
Although two are provided three by two, four or more may be provided.

FIG. 20 is a view showing a modification of the seventh embodiment, and is a front view (FIG. 20 (a)) and a plan view (FIG. 20 (b)). The optical waveguide 12 is the optical waveguide substrate 2
Divided into two around 2. There are two optical waveguide substrates 22, each having one optical waveguide 20. Optical waveguide 2
0 is connected to the optical waveguide 12 divided into two branches.

[0106]

According to the present invention, the height of the optical waveguide can be adjusted by holding the plurality of optical waveguide substrates by the holding plate. Moreover, since the holding plate holds the plurality of optical waveguide substrates, it is not necessary to provide a terrace on the optical waveguide substrate itself.

[Brief description of the drawings]

FIG. 1 is a front view (FIG. 1A) and a plan view (FIG. 1B) of an optical waveguide connection device 1 when an optical waveguide according to a first embodiment is connected.

FIG. 2 shows optical waveguide substrates 10 and 2 before connecting optical waveguides.
FIG. 3 is a front view of the reference numeral 0 and a holding plate 30.

FIG. 3 shows the optical waveguide substrates 10 and 2 before connecting the optical waveguides.
FIG. 2 is a plan view of a reference numeral 0 and a holding plate 30;

FIG. 4 is a front view showing a modification in which reflection of light is suppressed.

FIG. 5 is a front view of the optical waveguide connection device 1 when the optical waveguide according to the second embodiment of the present invention is connected (FIG. 5A).
And a plan view (FIG. 5B).

FIG. 6 shows a modification of the second embodiment, in which a spacer 6
The heights of the optical axes are adjusted with the heights of 0 and 70 being non-uniform (FIG. 6A), and the optical axis of the optical waveguide 12 is crossed with the optical axis of the optical waveguide 22 (FIG. 6A). It is a front view of (b)).

FIG. 7 is a front view (FIG. 7 (a)) and a plan view (FIG. 7 (b)) of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the third embodiment of the present invention is connected. ).

FIG. 8 shows the optical waveguide substrates 10 and 2 before connecting the optical waveguides.
FIG. 3 is a front view of the reference numeral 0 and a holding plate 30.

FIG. 9 shows optical waveguide substrates 10 and 2 before optical waveguides are connected.
FIG. 2 is a plan view of a reference numeral 0 and a holding plate 30;

FIG. 10 is a front view (FIG. 10 (a)) and a plan view (FIG. 10 (b)) of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the fourth embodiment of the present invention is connected. )
It is.

FIG. 11 shows an optical waveguide substrate 10 before connecting an optical waveguide,
FIG. 2 is a front view of a holding plate and a holding plate.

FIG. 12 shows an optical waveguide substrate 10 before connecting an optical waveguide,
FIG. 2 is a plan view of a holding plate 20 and a holding plate 30.

FIG. 13 is a front view (FIG. 13A) and a plan view (FIG. 13B) of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the fifth embodiment of the present invention is connected. )
It is.

FIG. 14 shows an optical waveguide substrate 10 before connecting the optical waveguide,
FIG. 2 is a front view of a holding plate and a holding plate.

FIG. 15 shows an optical waveguide substrate 10 before connecting the optical waveguide,
FIG. 2 is a plan view of a holding plate 20 and a holding plate 30.

FIG. 16 is a front view (FIG. 16A) and a plan view (FIG. 16B) of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the sixth embodiment of the present invention is connected. )
It is.

FIG. 17 shows an optical waveguide substrate 10 before connecting the optical waveguide,
FIG. 2 is a front view of a holding plate and a holding plate.

FIG. 18 shows an optical waveguide substrate 10 before connecting an optical waveguide,
FIG. 2 is a plan view of a holding plate 20 and a holding plate 30.

FIG. 19 is a front view (FIG. 19A) and a plan view (FIG. 19B) of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the seventh embodiment of the present invention is connected. )
It is.

20 is a front view (FIG. 20 (a)) and a plan view (FIG. 20) of a modification of the optical waveguide connecting device of the optical waveguide connecting device 1 when the optical waveguide according to the seventh embodiment of the present invention is connected.
(B)).

FIG. 21 is a cross-sectional view of a connection portion of an optical waveguide that has been aligned using a light source or an optical power meter in the related art.

FIG. 22 is a front view of a connection portion of an optical waveguide in which alignment is performed by providing a terrace on an optical waveguide substrate in the related art.

FIG. 23 is a plan view of a connection portion of an optical waveguide in which alignment is performed by providing a terrace on an optical waveguide substrate in the related art.

[Explanation of symbols]

 10, 20 Optical waveguide substrate 12, 22 Optical waveguide 12a, 22a AR coating 12b, 22b Inclined surface 14, 24 Optical waveguide substrate positioning marker 16, 26 Optical waveguide side metal pad 30 Holding plate 34 Holding plate positioning marker 36 Holding plate Side metal pad 42, 44 Adhesive 46 Refractive index matching agent 50 Positioning marker 60, 70 Spacer 60a, 70a Holding plate side spacer 60b, 70b Optical waveguide substrate side spacer 80 Solder bump

Claims (15)

[Claims] 1. An optical waveguide connection device comprising: a plurality of optical waveguide substrates on which optical waveguides are formed; and a holding plate for holding the plurality of optical waveguide substrates. 2. A plurality of optical waveguide substrates each having an optical waveguide formed thereon, a holding plate for holding the plurality of optical waveguide substrates, an optical waveguide substrate positioning marker indicating a position of the optical waveguide substrate, and the holding plate. And a holding plate positioning marker disposed at a position corresponding to the optical waveguide substrate positioning marker. 3. The optical waveguide connection device according to claim 2, further comprising: a spacer disposed between the plurality of optical waveguide substrates and the holding plate, for separating the plurality of optical waveguide substrates from the holding plate. . 4. The optical waveguide connection device according to claim 3, wherein the optical waveguide substrate positioning marker is formed on a surface of the optical waveguide substrate, and the holding plate positioning marker is formed on the spacer. . 5. The optical waveguide connection device according to claim 3, wherein the holding plate positioning marker is formed on a surface of the holding plate, and the optical waveguide substrate positioning marker is formed on the spacer. 6. The optical waveguide substrate-side spacer attached to the optical waveguide substrate, and a holding plate-side spacer attached to the holding plate, wherein the optical waveguide substrate positioning mark is a light guide. 4. The optical waveguide connection device according to claim 3, wherein the optical waveguide connecting device is formed on the waveguide substrate side spacer, and the holding plate positioning mark is formed on the holding plate side spacer. 5. 7. The optical waveguide connection device according to claim 1, further comprising fixing means for fixing the optical waveguide substrate and the holding plate. 8. The optical waveguide connecting device according to claim 7, wherein said fixing means is a UV curing adhesive or a thermosetting adhesive. 9. The optical waveguide connection device according to claim 3, wherein the height of the spacer is determined such that the optical axes of the plurality of optical waveguides have the same height. 10. The optical waveguide connection device according to claim 3, wherein the height of the spacer is determined so that the optical waveguides connected to each other intersect. 11. The optical waveguide connection device according to claim 1, wherein a difference between a thermal expansion coefficient of the holding plate and a thermal expansion coefficient of the optical waveguide substrate is within a predetermined value. . 12. The optical waveguide connecting device according to claim 1, wherein an AR coating is applied to an end face of said optical waveguide. 13. The optical waveguide connection device according to claim 1, wherein an end face of the optical waveguide is obliquely inclined with respect to an optical axis. 14. The optical waveguide connection device according to claim 1, wherein a refractive index matching agent is disposed between the optical waveguides connected to each other. 15. A plurality of optical waveguide substrates on each of which an optical waveguide and an optical waveguide-side metal pad are formed; a holding plate that holds the plurality of optical waveguide substrates and on which a holding plate-side metal pad is formed; A fixing means for fixing the optical waveguide substrate and the holding plate, the fixing means being formed by melting a solder bump formed on the side metal pad or the holding plate side metal pad.