JPH04195005A - Coupling method for optical fiber and lens - Google Patents

Abstract

PURPOSE:To align a distance between a lens and an optical fiber with an optical axis with nonadjustment by chamfering the side of the optical fiber of a G-iris at some angle, and obtaining a cut on the side of the lens of a middle sleeve for pressing it. CONSTITUTION:The side of the optical fiber 8 of the G-iris 6 is chamfered at some angle, and the cut 9 is obtained on the side of the lens 7 of the middle sleeve 5. Then, a rotary ring 2 is rotated, and the middle sleeve 5 is pressed toward the lens via a ferrule 4. Next, the cut 9 of the lens side of the middle sleeve 5 is moved along the chamfering of the G-iris 6. Further, the lens 7 is pressed/fixed on the opening part of an external cylinder 1 via the G-iris 6. Thus, fine adjustment after assembling can be carried out, and the number of assembling processes is reduced. Moreover, optical coupling is easily carried out, the lens is mechanically fixed, and a characteristic change caused by a temp. is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for optically coupling an optical fiber and a lens.

[Conventional technology]

The conventional coupling method of optical fiber and lens is disclosed in Japanese Patent Application Laid-Open No. 1986-
As in Japanese Patent No. 179707, it was possible to mechanically couple an optical fiber and a lens, and to match the distance between the lens and the optical fiber and the optical axis without any adjustment. However, such a fixing method has the drawback that fine adjustment is not possible when fine adjustment is required due to the dimensional accuracy of the optical fiber core diameter, the dimensional accuracy of the lens, etc.

[Problem to be solved by the invention]

In view of the above-mentioned prior art, the present invention combines an optical fiber and a lens, which has the function of aligning the distance between the lens and the optical fiber and the optical axis without any adjustment, and further finely adjusting the distance between the lens and the optical fiber. The purpose is to provide a method.

[Means to solve the problem]

In order to achieve the above purpose, G iris and G
In order to always press the iris against the lens, and to be able to vary the distance between the optical fiber and the lens, a notch is made on the lens side, and the inner sleeve, lens, and ferrule are processed as shown in Figure 2 to provide elasticity. is held in a precision sleeve, and is equipped with a threaded outer cylinder and a threaded rotating ring.

[Effect]

As the rotating ring rotates, the ferrule fitted with it moves within the precision sleeve. Accordingly, the elastic part of the middle sleeve pushes the G iris and fixes the lens. At the same time, the distance between the lens and the optical fiber can be varied to enable fine adjustment.

〔Example〕

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

1 is a diagram for explaining a method of coupling an optical fiber and a lens according to the present invention. In the same figure, 1 is an outer cylinder;
2 is a rotating ring, 3 is a precision sleeve, 4 is a ferrule,
5 is a middle sleeve, 6 is a G iris, 7 is a lens, and 8 is an optical fiber.

As the rotating ring 2 rotates, the ferrule 4 presses the middle sleeve 5 toward the lens.
The elastic part changes from the state shown in FIG. 1(b) to the state shown in FIG. 2(a),
The G iris 6 presses and fixes the lens against the opening of the outer cylinder 1. Further, it is possible to finely adjust the distance between the optical fiber 8 and the lens 7, and it is possible to compensate for variations in the core diameter dimension and the dimensional accuracy of the lens.

〔Effect of the invention〕

According to the present invention, since fine adjustments can be made after assembly, it is effective in reducing the number of assembly steps. Further, since optical coupling can be easily performed, the number of assembly steps can be reduced, and since the lens can be fixed mechanically, there is an effect that no change in characteristics due to temperature characteristics is observed.

[Brief explanation of the drawing]

Figures 1 (a) and (b) are diagrams for explaining the method of coupling the lens and optical fiber, and diagrams for explaining the function for finely adjusting the distance between the lens and the optical fiber. FIG. 3 is a detailed view of the sleeve. 1... Outer cylinder, 2... Rotating ring, 3... Precision sleeve, 4... Ferrule, 5... Middle sleeve, 6...
... G iris, 7... Lens, 8... Optical fiber, 9... Elastic part. 1st A (b) Sheep 2 A

Claims (1)

[Claims] 1. Fixing the lens to the ferrule that fixes the optical fiber in the center, and the G iris with a chamfered side on the optical fiber side so that the distance between the optical fiber end face and the lens can be varied.Always press the G iris against the lens, and An inner sleeve with a notch so that the distance between the lenses can be varied from the end face is placed inside the precision sleeve, and a threaded rotating ring is fitted into the threaded outer cylinder to rotate the rotating ring. A method for coupling an optical fiber and a lens, which is characterized in that the distance between the optical fiber end face and the lens can be finely adjusted easily and in a short time.