JPH04120501A - Structure for optical module - Google Patents

Abstract

PURPOSE:To couple an optical element and an optical fiber mutually in a best state by adjusting the distance between a surface A and the optical fiber end surface by using a stopper or cylindrical metallic fittings. CONSTITUTION:The optical element 1 is adjusted and fixed to an element holder 2 at a specific distance from the surface A. The end surface of an optical fiber terminal 4 is abutted on the stopper 6 fixed to the cylindrical metallic fittings 3 and fixed with a cap nut 5 so that the distance from the surface A is Zf. then this element holder 2 and stopper are abutted on each other on the surface A and joined to couple the optical element 1 and optical fiber terminal 4 in a Z-axial direction. Consequently, the best optical coupling between the optical element 1 and optical fiber is realized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of an optical module, and particularly to a Z-axis adjustment mechanism of an optical module.

[Conventional technology]

Conventionally, the structure of this type of optical module, as shown in FIG. It consisted of a cylindrical metal fitting 8 for holding and fixing the flange portion, and a cap nut 5.

[Problem to be solved by the invention]

In the conventional optical module structure described above, the distance Zf of the optical fiber end face with respect to the A side of the element holder 2 is mechanically determined by the protrusion amount J2z of the optical fiber terminal 4 from the flange. There is a problem in that the optical coupling between the optical element and the optical fiber is not optimal due to variations.

[Means to solve the problem]

The structure of the optical module of the present invention includes an optical element, an optical fiber terminal facing the optical element, a cylindrical element holder that holds the photons, an end face of the element holder, and an end face of the optical fiber terminal. a stopper for keeping the distance between
This stopper, a cylindrical metal fitting that holds the first optical fiber terminal, and a cap nut that holds and fixes the optical fiber terminal to the first cylindrical fitting while abutting the optical fiber terminal against the stopper.

Further, the structure of the optical module of the present invention is such that the swivel member and the cylindrical metal fitting are integrated.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

1 and 2 are longitudinal sectional views of first and second embodiments of the present invention.

In the first embodiment, as shown in FIG. 1, an optical element 1, an optical fiber terminal 4 provided opposite to this optical element 1,
A cylindrical element holder 2 that holds the optical element l, a stopper 6 for keeping the end face A of the element holder 2 and the end face of the optical fiber terminal 4 at a constant distance Zf, and a stopper 6 and the optical fiber terminal 4. The cylindrical metal fitting 3 to be held and the end face of the optical fiber terminal 4 are pressed against the stopper 6 while the cylindrical metal fitting 3 is held.
It has a cap nut 5 for holding and fixing it.

That is, the optical element 1 is adjusted and fixed to the element holder 2 at a predetermined distance from the A plane. The optical fiber terminal 4 is fixed with a cap nut 5 so that its end face abuts against a stopper 6 fixed to the cylindrical metal fitting 3 and the distance from the A plane is Zf. By joining the element holder 2 and the stopper 6 against each other on the A plane, the optical element 1 and the optical fiber terminal 4 are optimally coupled in the Z-axis direction.

Further, as shown in FIG. 2, the second embodiment includes a cylindrical fitting 7 in which the cylindrical fitting 3 and the stopper 6 of the first embodiment are integrated. In this case as well, by joining the element holder 2 and the cylindrical metal fitting 7 against each other on the A side, the distance between the A side and the end face of the optical fiber terminal 4 is maintained at Zf, and the optical element 1 and the optical fiber terminal 4 are Optimal coupling is achieved in the Z-axis direction.

〔Effect of the invention〕

As explained above, the present invention uses a stopper or a cylindrical metal fitting to adjust the distance Zf between surface A and the end face of the optical fiber, so that the protrusion amount Jl of the optical fiber end from the flange is adjusted.
This has the effect that the optical element and the optical fiber can be optimally coupled regardless of the variation in z.

[Brief explanation of the drawing]

1 and 2 are vertical sectional views of the first and second embodiments of the present invention, and FIG. 3 is a vertical sectional view of a conventional optical module structure. l... Optical element, 2... Element boulder, 3,7.8...
- Cylindrical metal fitting, 4... Optical fiber terminal, 5... Cap nut, 6... Stopper.

Claims (1)

[Claims] 1. An optical element, an optical fiber terminal facing the optical element, a cylindrical element holder holding the optical element, and an end face of the element holder and an end face of the optical fiber terminal. A stopper for maintaining a constant distance, a cylindrical metal fitting that holds the stopper and the optical fiber terminal, and a cap nut that holds and fixes the optical fiber terminal to the cylindrical metal fitting while abutting the optical fiber terminal against the stopper. Characteristic optical module structure. 2. The structure of the optical module according to claim 1, wherein the stopper and the cylindrical metal fitting have an integral structure.