JPS6235308A - Connecting method for light guide and optical fiber - Google Patents

Abstract

PURPOSE:To link the light guide and the optical fiber through the optical film semipermanently by forming the optical film at the prescribed edge surface of the substrate in the light guide, after the optical film and the light guide edge are unified, melting and unifying the edge part of the optical fiber at the optical film. CONSTITUTION:First, a prescribed edge surface 2a of a substrate 2 s optically ground, at the edge surface 2a after grinding, an optical film 4 composed of SiO2 through the glass evaporating means such as the sputter method is formed, and the edge part of a wave guide part 3 is unified with the optical film 4. Next, the edge part of an optical fiber 5 is abutted to the optical film 4, heated by the arc discharging, etc., and the edge part of the optical fiber 5 is adhered to the optical film 4 by fusion. Thus, the connecting part of a connected light guide 1 and the optical fiber 5 has the tensile strength equal to the case when the optical fiber is mutually adhered by fusion and connected, and for a long time, the dislocation will not occur at the light axis of the light guide path 1 and the optical fiber 5.

Description

DETAILED DESCRIPTION OF THE INVENTION r Industrial Application Field J The present invention relates to a method for optically connecting an optical waveguide and an optical fiber.

rPrior Art 1 Optical waveguides, such as planar optical demultiplexers (combiners) developed for optical wavelength multiplexing communications, are optically connected to optical fibers when used.

Generally, the above-mentioned optical waveguide has a Y-shaped or Y-shaped waveguide (core) formed on a substrate through processes such as glass deposition, photolithography, and dry etching. Each end extends to both ends of the substrate.

When connecting an optical fiber to the waveguide portion of such an optical waveguide, bonding means using an adhesive or means using a support stand for integrally coupling the optical waveguide and the optical fiber are employed.

rProblem to be solved by the invention J In the case of the above-mentioned adhesive means, when the adhesive hardens, shrinkage causes a misalignment in the coupling between the waveguide part of the optical waveguide and the optical fiber, which causes the characteristics of the connection part to change. descend.

On the other hand, in the method using a support stand, a groove for fitting the optical fiber is formed in the support stand, and the waveguide part of the optical waveguide and the optical fiber are coupled through the groove. The grooves must be formed so as to obtain the best bonding condition, which is extremely difficult to process.

In view of the above-mentioned problems, the present invention provides a connection method in which the waveguide part of an optical waveguide and the end part of an optical fiber can be coupled in the best possible state by a simple means, and in which the coupled state can be maintained semi-permanently. This is what I am trying to do.

Means for Solving Problem 1 The present invention provides a method for interconnecting an optical waveguide having a waveguide portion on a substrate and an optical fiber, in which an optical film is provided on the end surface of the substrate where the end of the waveguide portion is located. The optical film is formed to integrate the optical film and the end of the waveguide, and the end of the optical fiber is fused to the optical film.

1 Effect J In the case of the method of the present invention, an optical film is formed on a predetermined end face of the substrate, the optical film and the end of the waveguide are integrated, and the end of the optical fiber is fused to the optical film. The wave portion and the optical fiber are semi-permanently coupled via an optical film.

Moreover, since an optical film is simply formed on the end surface of the substrate corresponding to the end of the waveguide and the optical fiber is fused to the optical film, the optical axes of the waveguide and the optical fiber can be aligned with each other. This can be done easily and accurately through a membrane, and therefore the best bonding state between the two can be easily obtained.

EXAMPLE 1 An example of the method of the present invention will be described below with reference to one drawing.

In FIG. 1, 1 is an optical waveguide, and this optical waveguide l
For example, a quartz-based waveguide portion 3 is formed on a substrate 2 made of lithium tantalate.

First, a predetermined end surface 2a of the substrate 2 is optically polished, and an optical film 4 made of Si02 is formed on the end surface 2a after polishing using glass deposition means such as sputtering as shown in FIG. The end portions of the wave portions 3 are integrated with this optical film 4.

Next, as shown in FIG. 2, the end of the optical fiber 5 made of a known quartz-based material is brought into contact with the optical film 4, and the contact portion is heated by arc discharge or the like, so that the end of the optical fiber 5 becomes optical. It is fused to the membrane 4.

The optical waveguide 1 and optical fiber 5 thus connected are in the state shown in FIG. 3.

The connection portion between the optical waveguide 1 and the optical fiber 5 connected as described above had a tensile strength equal to that of the case where the optical fibers were fused together.

In order to confirm the aging characteristics of the above-mentioned connection, we compared the amount of light transmitted immediately after connection with the amount of light transmitted a considerable amount of time after that, and found that there was no change in the amount of transmitted light. It was found that no deviation occurred in the optical axes of the wave path 1 and the optical fiber 5.

Effects of the Invention J As explained above, according to the connection method of the present invention, after forming an optical film on a predetermined end surface of a substrate in an optical waveguide and integrating the optical film and the end of the optical waveguide, the optical Since the end of the optical fiber is fused and integrated with the film, the waveguide part of the optical waveguide and the end of the optical fiber can be coupled by a simple means, and the best possible coupling can be achieved through the optical film. state can be obtained, and the bonded state can be maintained semi-permanently without changing over time.

[Brief explanation of the drawing]

FIGS. 1 to 3 are explanatory diagrams schematically showing an embodiment of the method of the present invention in the order of its steps. 1・Φ・Optical waveguide 2...Substrate 2a of the optical waveguide...End surface 3 of the substrate...-Waveguide part 4 of the optical waveguide 4◆・-Optical film 5・-φ optical fiber

Claims (1)

[Claims] In a method for interconnecting an optical waveguide having a waveguide on a substrate and an optical fiber, an optical film is formed on the end surface of the substrate where the end of the waveguide is located, and the optical film and the end of the waveguide are integrated. 1. A method for connecting an optical waveguide and an optical fiber, the method comprising: forming an optical film, and fusing the end of the optical fiber to the optical film.