JP2995605B2 - Optical switch manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a fiber movable mechanical optical switch used for optical communication and the like.

[0002]

2. Description of the Related Art A mechanical optical switch having a structure in which an optical fiber is directly driven to switch an optical path is characterized by a simple structure, low insertion loss, miniaturization, and low driving power. Many types of switch structures have been proposed so far. Among them is an optical switch shown in FIG. 5 (see FIG. 5).

FIG. 5A is a perspective view showing the structure of an optical switch. This mechanical optical switch is of the 1 × 2 type, and its base is fixed to a cylindrical tube 5 in a cantilever shape, and a single movable body having a magnetic body 7 having desired magnetic properties fixed to a surface near the tip thereof. A bare optical fiber 1, a hollow solenoid coil 4 provided for reversing the magnetic poles at both ends of the magnetic body, and a pair of permanent magnets 6 for applying a magnetic attraction to the magnetic body in a direction perpendicular to the optical axis; Two fixed bare optical fibers fixed on a V-shaped groove formed in a flat part of a half cylinder 2, a cylindrical sleeve for aligning and holding a cylindrical tube 5 and a half cylinder, and fixing a solenoid coil and a permanent magnet. 20.

FIG. 5 (b) is a cross-sectional view of the half cylinder 2, showing a state where the fixed bare optical fiber 3 is fixed in a V-groove. The method of setting the gap between the fixed bare optical fiber and the movable bare optical fiber in the manufacturing process of the present switch is as follows. FIG. 4 is an explanatory view of a conventional manufacturing process. That is, the fixed bare fiber 3 fixed on the V-shaped groove 9 formed in the flat portion of the half cylinder and the hollow solenoid coil 4 wound on the bobbin 41 are held by the fixture 16 on the jig. . Further, the cylindrical tube 5 in which one bare optical fiber 1 is inserted is held, and pressure is applied in the optical axis direction by utilizing the elasticity of the fiber so that a gap is generated between the bare optical fiber 1 and the fixed bare optical fiber 3. Is fixed with an adhesive tape 1a. Then, the bare optical fiber 1 is moved in the optical axis direction while applying pressure by a push rod 18 in a direction perpendicular to the optical axis to perform fine adjustment, and at the same time, an insertion loss is measured to obtain a predetermined gap. After that, a quick-setting adhesive is applied from a groove provided in the cylindrical tube 5 to temporarily fix the cylindrical tube 5 and the bare optical fiber 1, and further, a thermosetting adhesive is applied. With the bare optical fiber 1 temporarily fixed, the cylindrical tube 5 is removed from the jig, and is heated and cured in a thermostat to be fixed. After the curing, the cylindrical tube was mounted on the jig again, and the gap between the bare optical fiber 1 and the fixed bare optical fiber 3 was confirmed.

[0005]

In a conventional manufacturing method, an optimum pressing force cannot be applied to the movable bare optical fiber in a direction perpendicular to the optical axis, and the tip of the movable bare optical fiber is V
It is not stuck to the groove and lifts up, resulting in unstable insertion loss. Further, in order to obtain a low insertion loss without being in close contact, the predetermined gap becomes small, and the fixed bare optical fiber may come into contact with the movable bare optical fiber during the actual assembly. Further, when the movable bare optical fiber is pressed by the push rod, the movable bare optical fiber is damaged or stained. In addition, during long-time heating and curing in a thermostatic oven, by removing the cylindrical tube from the jig in a temporarily fixed state, the length of the movable bare optical fiber varies, and the yield decreases. For this reason, after curing, the jig is placed again on the jig, the gap is checked, and the insertion loss is measured. This requires a lot of time in manufacturing.

According to the present invention, the movable bare optical fiber 1 is accurately brought into close contact with the V-shaped groove 3 on the half-column 2 and the predetermined gap is set optimally. The purpose is to shorten the manufacturing time by bonding and fixing on the tool.

[0007]

In order to achieve the above object, according to the manufacturing method of the present invention, the V
A cylindrical tube into which a movable bare optical fiber having a half cylinder, a solenoid coil, and a magnetic material (hereinafter, a movable bare optical fiber with a magnetic material) is placed in the groove. Then, a constant pressure is applied in the optical axis direction, and the movable bare optical fiber with the magnetic material inserted into the cylindrical tube is magnetically attracted with a constant magnetic force in a direction perpendicular to the optical axis. In the suction state, the movable bare optical fiber is finely adjusted in the direction of the half cylinder to obtain a gap. A thermosetting adhesive is applied in a state where a predetermined gap and an insertion loss are accurately set, and the cylindrical tube and the adhesive are heated and fixed by a heater provided on the jig.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall layout diagram showing a method of mounting members on a dedicated jig in the manufacturing method of the present invention.

The dedicated jig includes a half-column 2 to which the fixed bare optical fiber 3 is fixed, a V-shaped groove 9 for holding and fixing the solenoid coil 4 wound around the bobbin 41, and a half-column 2. Leaf spring 1 for applying a constant pressure in the optical axis direction
0, and a movable holding table having a permanent magnet 6 for magnetically attracting the movable bare optical fiber 1 having a magnetic body 7 in a direction perpendicular to the optical axis (hereinafter, a movable bare optical fiber with a magnetic body) in the paper back direction. 11 and a grooved cylindrical tube 5 having a heating element 12
A holding table 13 for holding the core 8 and a holding table 14 for holding the core 8, and a fine adjustment table 15 capable of finely adjusting the core 8 through the holding base 14 in the optical axis direction are attached. Further, a fixture 16 for fixing each member is attached to the upper part of each holding table.

In FIGS. 2 and 3, the movable bare optical fiber 1 with a magnetic body inserted into the cylindrical tube 5 and the stationary bare fiber 3 bonded and fixed to a half-column are shown in FIGS.
FIG. 3B shows a manufacturing process in which a gap invisible in FIG. 3A is obtained, and the movable bare optical fiber 1 is bonded and fixed to the cylindrical tube 5.

FIG. 2A is a cross-sectional view of the member mounting portion as viewed from below in FIG. As shown in FIG. 2A, the half cylinder 2 and the solenoid coil 4 are
The cylindrical tube 5 into which the movable bare optical fiber with magnetic material 1 has been inserted is similarly placed and fixed on the heating table 12 fixed on the holding table 13. Figure 2 shows the fixing method
(B). The half cylinder 2, the solenoid coil 4, and the cylindrical tube 5 are fixed to the V-shaped groove 9 on the holding table 11 or the heating table 12, respectively, using a fixture 16 utilizing spring pressure.

Next, the movable holding table 11 on which the half cylinder 2 and the solenoid coil 4 are fixed is moved in the direction of the optical axis, and the half cylinder 2 and the solenoid coil 4 are further joined to the cylindrical tube 5. A constant pressure is applied to the half cylinder 2 by the spring 10 in the optical axis direction. This state is shown in FIG.

FIG. 3B is an enlarged explanatory view of the half cylinder 2 and the solenoid coil portion in FIG. 3A as viewed from above. In FIG. 3A, the movable bare optical fiber with magnetic material 1 inserted into the cylindrical tube 5 is magnetically attracted by a permanent magnet 6 in a direction perpendicular to the optical axis. At this time, as shown in FIG. 3B, the bare optical fiber 1 is aligned with the V-shaped groove on the half cylinder 2 and is connected to the fixed bare optical fiber 3 at a certain interval. After that, the fine moving table 15 installed on the holding table 14
The movable bare optical fiber 1 is finely adjusted by moving the core portion 8 mounted and fixed in the optical axis direction, an appropriate gap between the two fibers is obtained, and the optical fiber is inserted into the adhesive injection groove provided in the cylindrical tube 5. Apply adhesive. Then, it comprises a step of heating and curing at a set time and temperature.

[0014]

Since the present invention is configured as described above, it has the following effects. A fixed pressure is applied to the fixed bare optical fiber in the optical axis direction through a half cylinder by a leaf spring on the dedicated jig, and a magnetic attraction is performed by a permanent magnet in a direction perpendicular to the optical axis. Since the movable bare optical fiber with magnetic material is closely aligned with the V-shaped groove of the half cylinder, the gap between the fibers and the insertion loss are appropriate and accurate, and can be set to the same value as in the final assembly.

Further, when the movable bare optical fiber with the magnetic material is aligned with the V-shaped groove of the half cylinder, the use of the push rod is eliminated, so that the fiber can be prevented from being stained or damaged. Also,
By providing the fine movement adjusting mechanism, a predetermined minute gap can be accurately obtained at the time of adjusting the gap.

Further, since the heating tool is attached to the special jig, the adhesive can be hardened on the special jig without removing the cylindrical tube, so that the work is easy and the manufacturing time is reduced. Can be shortened.

[Brief description of the drawings]

FIG. 1 is an overall layout view showing a method of mounting members on a dedicated jig in a manufacturing method of the present invention.

FIG. 2A is a cross-sectional view of a member mounting portion viewed from below in FIG. 1, and FIG. 2B is a cross-sectional view illustrating a method of fixing the member.

3A is a cross-sectional view at the time of a gap adjusting and adhesive applying step according to the present invention, and FIG. 3B is an enlarged explanatory view of the solenoid coil portion of the half cylinder in FIG.

FIG. 4 is an explanatory diagram of an overall arrangement showing a conventional method.

FIG. 5A is a perspective view showing the structure of a 1 × 2 optical switch to which the present invention is applied, and FIG. 5B is a sectional view of a half-cylindrical column to which a fixed bare optical fiber is fixed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Movable bare optical fiber with a magnetic body 2 Half cylinder 3 Static bare optical fiber 4 Solenoid coil 5 Cylindrical tube with a groove 6 Permanent magnet 7 Magnetic body 8 Core part 9 V-shaped groove 10 Leaf spring 12 Heating body 15 Fine moving table

Claims (1)

(57) [Claims] A first end face of a first optical fiber having a front end fixed in a V-groove; and a second end having a magnetic body near the front end, wherein the front end is movable in a direction perpendicular to an axis. In the method of manufacturing an optical switch for conducting by facing the end face of the optical fiber of the optical fiber in the V groove,
The distal end of the second optical fiber is applied by a magnet in a direction perpendicular to the axis through the magnetic material, so that the tip of the second optical fiber is moved in the axial direction while being in close contact with the V-groove. A method for manufacturing an optical switch, comprising: measuring a conduction loss between a fiber and the second optical fiber to determine an optimum gap; and then fixing the second optical fiber in an axial direction.