JPH0843677A - Connecting jig and connecting method for optical waveguide and optical fiber. - Google Patents

Abstract

PURPOSE:To provide a connecting jig for an optical waveguide and optical fibers of a low loss capable of positioning one piece each even at the time of connecting many pieces of fibers and aligning the axes of rotation of the fibers without requiring fore stages. CONSTITUTION:The connecting jig 1 for the optical fiber 3 having a diameter(d)and the optical waveguide chip 2 having a distance(t) between the center of a core part 4 and the base of the jig is composed of an optical waveguide holding part 1a longer by a prescribed length than the length of the optical waveguide chip 2 and an optical fiber supporting base 1b of height lower by a prescribed value lower than t-d/2 than the optical waveguide holding part 1a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jig for connecting an optical waveguide and an optical fiber and a connecting method.

[0002]

2. Description of the Related Art When a waveguide and a fiber are directly connected and fixed with a UV curable resin, an adhesive or the like, the adhesion area is at most about the cross-sectional area of the fiber, the adhesion is weak, and the mechanical strength becomes a practical problem.

As a method of connecting the waveguide and the fiber, the main method conventionally used is to harden the fiber by a glass block or the like and increase the adhesive area by adhering it to the waveguide.

[0004]

However, in this method, as shown in FIG. 4, it is necessary to perform a pre-process such as polishing the rear end face of the optical fiber 3 fixed to the fixed block 10 in advance. In order to connect to the waveguide, it is necessary to fix the optical fiber 3 to the fixed block 10 on the array, and simultaneously align a large number of waveguides and the optical fiber 3 when the connection is fixed. There is a drawback in that it is practically difficult to align the rotation axis of the optical fiber 3 necessary for aligning the main axis with the main axis of the waveguide.

In view of the above situation, an object of the present invention is that it does not require a pre-process, enables positioning one by one even when a large number of fibers are connected, and also adjusts the rotation axis of the fibers. It is to provide a low loss optical waveguide and optical fiber connection technology that is possible.

[0006]

A jig for connecting an optical waveguide and an optical fiber according to the present invention is used for connecting an optical waveguide having a distance t between a center of a core and a bottom surface and an optical fiber having a diameter d. In the jig, an optical waveguide holding portion that is longer than the length of the optical waveguide by a predetermined length, and an optical fiber support base that has a height lower than t-d / 2 by a predetermined value from the optical waveguide holding portion. Characterize.

In the method of connecting an optical waveguide and an optical fiber according to the present invention, the optical waveguide is installed in a jig for connecting the optical waveguide and the optical fiber at a predetermined distance from the optical fiber support. After aligning the core and the optical fiber, a UV curable resin or an adhesive is applied and connected and fixed to a portion from the optical fiber support to the end face of the optical waveguide.

[0008]

With these connecting jigs and connecting methods, there is no need for a pre-process, and even when connecting many fibers, it is possible to align the fibers one by one, and to easily align the rotation axis of the fibers. It is possible to provide a technique for connecting and fixing a waveguide and an optical fiber.

[0009]

FIG. 1 is a diagram for explaining a first embodiment of the present invention, which is made of quartz glass and has an optical waveguide holding portion 1a having a width of 60 mm and a length of 70 mm, a step difference of 700 μm and a width of 6 mm.
A jig 1 for connecting an optical waveguide and an optical fiber, which is composed of an optical fiber support 1b having a length of 0 mm and a length of 10 mm, is manufactured, and a flame deposition method is applied to a silicon substrate having a thickness of 0.8 mm, a width of 50 mm and a length of 49 mm. Fix the silica-based optical waveguide chip 2 manufactured by photolithography (the distance t between the center of the core portion 4 of the optical waveguide chip 2 and the bottom of the jig 1 for connecting the optical waveguide and the optical fiber at this time is 0.85 mm) did.

Two single mode optical fibers 3 having a diameter d of 125 μm were fixed to the both ends by UV curable resin. The step of the step portion is t-d
/ 2-300 μm to t-d / 2 is preferable.

According to this embodiment, the excess loss due to the connection drop was 0.1 dB on average at one end at the light wavelength of 1.3 μm.

FIG. 2 is a view for explaining the second embodiment of the present invention, in which aluminum is used and the width is 10 mm and the length is 20 mm.
mm optical waveguide holding portion 1a and the step difference of the step 250 μ
m, width 10 mm, length 5 mm optical fiber support 1b
A jig 1 for connecting an optical waveguide and an optical fiber, which is composed of and, was prepared by a liquid phase epitaxial method and photolithography on a gadolinium-gallium-garnet substrate having a thickness of 0.4 mm, a width of 5 mm and a length of 3 mm. The optical waveguide chip 2 (t at this time is 0.4 mm) made of a magnetic material was fixed.

Four single-mode panda-type optical fibers 3 having a diameter d of 125 μm were fixed to the both ends by UV curable resin.

At this time, the principal axes of polarization of the respective optical fibers 3 are aligned parallel, perpendicular, and ± 45 ° with respect to the waveguide substrate as shown in the figure.

After the adhesive fixing with the UV resin, the fiber jacket (optical fiber support 1b) was further reinforced by the optical fiber fixing jigs 6 and 7 made of the same material (aluminum) as the jig 1 for connecting the optical waveguide and the optical fiber.

According to this embodiment, at the light wavelength of 1.55 μm, the excess loss due to the connection processing is 0.2 dB on average at one end.
Met.

FIG. 3 is a diagram for explaining the third embodiment of the present invention, in which polymethyl methacrylate is used and the width is 10 m.
m, length 20 mm, optical waveguide holding portion 1a, step difference 250 μm, groove 1c width 150 μm, groove 1c height 200
A jig 1 for connecting an optical waveguide and an optical fiber, which is composed of an optical fiber support 1b having a length of μm and a length of 5 mm, is prepared.
Magnetic waveguide chip 2 made of magnetic material (t at this time is 0.4 mm) made on the gadolinium-galium-garnet substrate with a thickness of 0.4 mm, a width of 5 mm, and a length of 3 mm by the liquid phase epitaxy method and photolithography. Fixed.

Four single mode optical fibers 3 having a diameter d of 125 μm were fixed to the both ends with epoxy adhesives at both ends.

After bonding and fixing with an epoxy adhesive, the fiber jacket was further reinforced by a fiber connection reinforcing jig 8 made of the same material (polymethylmethacrylate) as the jig 1 for connecting the optical waveguide and the optical fiber.

According to the present embodiment, at the light wavelength of 1.55 μm, the excess loss due to the connection processing is 0.3 dB on one end average.
Met.

In the above-mentioned embodiments, only quartz glass, aluminum and polymethylmethacrylate are used as the jig 1 for connecting the optical waveguide and the optical fiber, and the present invention is not limited to other materials. It is valid.

[0022]

As is clear from the above embodiments, according to the present invention, no pre-process is required, and even when a large number of fibers are connected, they can be aligned one by one and the rotational axes of the fibers can be aligned, and It is possible to connect a low loss optical waveguide and an optical fiber.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention.

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

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

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

[Explanation of symbols]

 1 Optical waveguide and optical fiber connection jig 2 Optical waveguide chip 3 Optical fiber 4 Optical waveguide core 5 Fixing block 6,7 Optical fiber fixing jig 8 Fiber connection reinforcing jig

Claims (8)

[Claims] 1. A connection jig for connecting an optical waveguide having a distance t between the center of the core and the bottom surface to an optical fiber having a diameter d, wherein the optical waveguide holding is longer than the length of the optical waveguide by a predetermined length. And a jig for connecting the optical waveguide and the optical fiber, which comprises a portion and an optical fiber support having a height lower than t-d / 2 by a predetermined value from the optical waveguide holding portion. 2. The jig for connecting an optical waveguide and an optical fiber according to claim 1, wherein the height of the optical fiber support from the optical waveguide holding portion is td / 2-300 μm. 3. The optical waveguide and the optical fiber according to claim 1, further comprising an optical fiber fixing jig having a thermal expansion coefficient similar to that of a jig for connecting the optical waveguide and the optical fiber, adjacent to the optical fiber support. Connection jig. 4. The jig for connecting an optical waveguide and an optical fiber according to claim 1, wherein the optical fiber support has an alignment groove portion for aligning the optical fibers. 5. The jig for connecting an optical waveguide and an optical fiber according to claim 1, wherein the optical fiber support is provided at both ends. 6. The material according to claim 1, wherein the material is quartz glass, aluminum or polymethylmethacrylate.
A jig for connecting the optical waveguide and the optical fiber according to 3, 4, or 5. 7. The optical waveguide according to claim 1, 2, 3, 4, 5 or 6, wherein the optical waveguide is installed at a predetermined distance from the optical fiber support base in the jig for connecting the optical waveguide and the optical fiber. After aligning the core of the waveguide and the optical fiber, a UV curable resin or an adhesive is applied to the portion from the optical fiber support to the end face of the optical waveguide to connect and fix the optical waveguide and the optical fiber. Method. 8. The optical fiber according to claim 3, wherein the UV curable resin or adhesive is applied to connect and fix the optical waveguide and the optical fiber, and then the optical fiber is fixed by using the jig for fixing the optical fiber. How to connect waveguide and optical fiber.