JPH03144518A - Optical switching unit - Google Patents

Abstract

PURPOSE:To automatically adjust optical axes between an outgoing side fiber and an incident side fiber and to switch light by inserting the incident side fiber in a positioning tube provided corresponding to the plural outgoing side fibers with the aid of an inserting and pulling switch. CONSTITUTION:The positioning tube 2 which is provided corresponding to each outgoing side fiber 1 and where the outgoing side fiber 1 is inserted halfway to be fixed and the inserting and pulling switch 6 which makes the incident side fiber 5 move toward the desired outgoing side fiber 1 and inserts it in the positioning tube 2 are provided. When the switch 6 is actuated to make an actuation piece 6b protrude after it moves any part of the outgoing side fiber 1 by a moving mechanism, the end of the incident side fiber 5 is inserted in the tube 2 and the incident side fiber 5 and the outgoing side fiber 1 are optically coupled inside the tube 2. At such a time, the incident side fiber 5 is easily inserted because the end 22 of the tube 2 is tapered. Thus, the accurate adjustment of optical axes is made needless and the optical axes are easily adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical switch that switches optical transmission lines such as optical fibers.

[Conventional technology] Conventional optical switching devices are shown in FIGS. 5 to 7.

What is shown in FIG. 5 is a prism 60a that moves on the optical axis.
~60e, the input fiber 61
The light is made into parallel light between the rod lenses 62, and is emitted to any of the output side fibers 63a to 63f by moving any of the prisms 60.

What is shown in FIG. 6 is a configuration in which output side fibers 70a to 70h and rod lenses 71 are arranged circumferentially, and input side fibers 72 and rod lenses 73 are arranged at the center. A rotatable mirror 74 is located below the input fiber 72 and at the center of the output fiber 70.
The mirror 74 is rotated by a motor (not shown), and the light from the input fiber 72 is emitted to one of the output fibers 70a to 70h.

7(a) and 7(b), each output side fiber 81a to 81 is attached to the outer circumferential portion of a radially formed V groove 80.
d (actually more fibers) are fixedly arranged, and the input side fiber 82 is rotatably arranged in the central part.6The input side fiber 82 is rotated by a rotation mechanism (not shown), and then By being pressed against the groove 80 portion, the fiber ends are optically connected directly to any output side fiber 81.

[Problem to be solved by the invention] However, in the optical switching device shown in FIGS. 5 and 6,
Precise optical axis alignment is required between the input side fiber and the output side fiber, and for this purpose, the system shown in Figure 5, which is characterized by precision parts and precision assembly, has parallel light between the rod lenses. Due to the limitation on the distance of parallel light, it was not possible to switch multiple sets of light.

In addition, the devices shown in FIGS. 5 and 6 require a holder, rod lens, etc. for fixing the output side fibers, which requires space for these parts, and there is a limit to the close arrangement of the output side fibers. As a result, it was not possible to provide many output fibers in a limited space.

On the other hand, in the one shown in Fig. 7, the V-groove 80 allows the input side and output side fibers to face each other with high precision, but the machining accuracy of 80 mm affects splice loss and reproducibility. At the same time, since the spacing between the ends of the input fiber and the output fiber must be constant, precision is required for this purpose.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide an optical switching device that does not require precise optical axis alignment and allows easy axis alignment.

[Means for Solving the Problems] In order to achieve the above object, an optical switching device of the present invention switches an optical path between an input side fiber and a plurality of output side fibers, and in claim 1, each output side fiber a positioning tube in which the output side fiber is inserted and fixed to a halfway position, and an insertion/extraction switch that moves the input side fiber in the direction of a desired output side fiber and inserts it into the positioning tube. It is characterized by

In addition, in claim 11, claim 2 includes: a circular fixed plate having positioning tubes arranged around the periphery thereof corresponding to the plurality of output side fibers according to claim 1; a rotary plate for rotating the input side fibers; and an optical coupling section consisting of a pair of rod lenses, one of which is provided on the fixed side and the other is provided on the rotary plate.

[Function] According to claim 1, the optical axis is automatically aligned between the input side fiber and the output side fiber by inserting the input side fiber into a positioning tube provided corresponding to a plurality of output side fibers using an insertion/extraction switch. , the light can be switched.

In claim 2, the plurality of output side fibers are arranged circumferentially, and the input side fiber is rotated by a rotary plate, and an optical coupling part is provided at a midway position of the input side fiber, Even if the rotating plate rotates, the input fiber will not be twisted.

[First Embodiment] FIG. 1 is a schematic diagram showing a first embodiment of an optical switching device according to the present invention.

As shown in the figure, a plurality of output side fibers 1 (la to ldl are the corresponding positioning tubes 2 (2a to 2d)
It is inserted and fixed to the halfway position of l. Positioning tube 2
is molded into a cylindrical shape having the same inner diameter as the outer diameter of the output side fiber 1, and uses a precision tube that is normally used for connecting the ends of the fibers.

The precision tube has a tapered end 22. Alternatively, a ceramic sleeve may be used as the positioning tube 2.

The positioning tubes 2 are fixed to the fixing plate 3 at predetermined intervals. Further, the positioning tube 2 is fixed to a support (not shown),
This support may be fixed to the fixing plate 3. Note that the fixture 3 fixes the positioning tube 2 so as to be positioned on the insertion direction of the input side fiber 5, which will be described later.

An input fiber 5 is provided on the end 22 side of the positioning tube 2 so as to be movable in the direction of the output fiber 1. The end of this fiber 5 on the input side is.

It is movable in two directions of the positioning tube by the insertion/extraction switch 6.

This insertion/extraction switch 6 is constituted by a solenoid 6a, and is used to fix and hold the end of the input fiber 5 with an operating piece 6b.

The end of the input fiber 5 is attached to the actuating piece 6b via a spring 6C.

According to the above configuration, after the insertion/extraction switch 6 is moved to one of the output side fibers 1 by the moving mechanism (not shown),
When the insertion/extraction switch 6 is operated and the operating piece 6b protrudes, the end of the input fiber 5 is inserted into the positioning tube 2, and the input fiber 5 and the output fiber l are optically coupled inside the positioning tube 2. Ru. At this time, since a taper is formed at the end 22 of the first positioning tube 2, the input fiber 5 can be easily inserted therethrough.

By the way, the impact force at this time of collision is a certain - constant value (4
gf) It is desirable to have the following. This impact force is absorbed by the spring 6C.

FIG. 2(a) shows an enlarged view of an application of the first embodiment in which ferrules 10 are provided at the end of the input fiber 5 and the end of the output fiber 1, respectively. The ferrules 10 at the ends of the input fiber 5 and the output fiber 1 are both convex, and there is little reflection at the joint, which reduces optical loss.

In addition, as shown in FIG. 2(b), a large diameter positioning tube 2
By providing a lens unit 12a in which a ferrule 1O and a rod lens 11 are provided, and by providing a similar lens unit 12b at the tip of the input fiber 5,
The lens unit 12b may be inserted into the positioning tube 2. In this case, the rod lenses 11, l1
Since the space between the two is considered to be parallel light, there is no need to hit it, and
Axial misalignment does not affect optical coupling.

When single mode fibers are used as the input side fiber 5 and the output side fiber 1, the cladding outer diameter may be 126 μm.

In addition, the precision tube used as the positioning tube 2 has an inner diameter of 126 (
+0. Since there is one with an accuracy of OOl, -〇), the maximum axis deviation is 0.5 μm.

However, L: axis misalignment loss, ω: spot size d: axis misalignment amount When the axis misalignment loss at this time is calculated using the above formula, -0,
It becomes 005dB. (When the spot size is 4.7 μm) Therefore, it is clear that the influence of angular misalignment, which has a larger effect than axis misalignment loss, is also smaller than when using the conventional V-groove.

[Second example] FIG. 3 is a schematic diagram showing a second embodiment of the present invention.

In this embodiment, the configuration of the first embodiment is used, and the input fiber 5 is configured to rotate.

As shown in the figure, by providing a coaxially rotating rod lens 14 provided on the rotation axis of the output side fiber l at a part A (optical coupling part) in the middle of the input side fiber 5, the moving input side fiber 5 can be moved in the part A part in the middle. Since the configuration is such that the optical coupling part A is used as a boundary, the input fiber 5 on the output fiber 1 side can be moved arbitrarily. In particular, when the input fiber 5 rotates to select any of the output fibers 1a to 1d, the input fiber 5 is not twisted at this portion A.

FIG. 4 is a perspective view showing the specific structure of the above embodiment.

A circular fixing plate 3 is fixed inside the housing 15, and holes 3a corresponding to the plurality of positioning tubes 2 are formed in the peripheral edge of the fixing plate 3. The positioning tube 2 is fixed. Here, as the fixed plate 3, 0
．． By using a 5mm stainless steel plate, etching the hole 3a allows for highly accurate positioning (error of 100μm).
(below) can be done. In addition, since the positioning tubes 2 can be fixed to the fixed plate by adhesive etc., the arrangement interval between the plurality of positioning tubes 2 can be reduced.
Therefore, a large number of output side fibers can be provided with high density, and a large number of optical switching can be achieved.

In order to horizontally fix the positioning tube 2, a pair of fixing plates 3 are provided as shown in the figure to fix the positioning tube 2. Further, the respective output side fibers l are collectively led out to the outside in an output boat 16b.

On the other hand, the input fiber 5b is led out from the input boat 16a to the central end of the fixed plate 3. The optical coupling portion is provided at the center of the fixing plate 3. In other words, the lens unit 12
a is provided on the fixed plate 3 side, and the 1 Lux unit 12b is provided on the rotary plate 17 side.

The rotary plate 17 has a long plate shape and is designed to have small inertia, and the insertion/extraction switch 6 is provided at the end of the rotary plate 17 at a position corresponding to the positioning tube 2. The insertion/extraction switch 6 and the lens unit 12b are connected by an incident side fiber 5.

Further, the center portion of the rotating plate (7) serves as a rotating shaft 19a of the stepping motor 19.

Therefore, the insertion/extraction switch 6 is rotated to the desired positioning tube 2 portion by the rotational drive of the stepping motor 19.
Thereafter, the insertion/extraction switch 6 is operated, so that the input fiber 5 is inserted into the positioning tube 2 .

Incidentally, since the stepping motor 19 is used to rotate the rotary plate 7, highly accurate positioning can be performed.

The positional accuracy of the stepping motor is 40 μm, which is sufficient accuracy.

Therefore, the taper of the end 22 of the positioning tube 2 allows the input fiber 5 to be inserted into the desired positioning tube 2 in an automatically positioned state.

[Effects of the Invention] According to claim 1, optical axis alignment by optical switching between the input side fiber and a plurality of output side fibers can be automatically achieved by simply inserting the input side fiber into the positioning tube using the positioning tube. Accuracy can be obtained.

According to claim 2, it is possible to obtain a large number of optical switches with a simple structure, a small space, and high precision.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a first embodiment of the optical switching device of the present invention, FIGS. 2(a) and (b) are partially enlarged cross-sectional views of the same embodiment, and FIG. A schematic diagram showing the second embodiment, FIG. 4 is a perspective view showing the specific configuration of the second embodiment, FIG.
FIG. 6, FIG. 7(a), and FIG. 7(b) are diagrams each showing a conventional optical switching device. 1 (la-1d)... Output side fiber, 2 (28-2
d)...Positioning tube, 3...Fixing plate, 3a...-hole, 5...Incidence side fiber, 6...Insertion/extraction switch, 1
0... Ferrule, 11... Rod lens, 12a
, 12b... Lens unit, A... Optical coupling part, 1
5... Housing, 16a... Injection boat, 1.6 b.
...Ejection boat 517...Rotary plate, 19...Stepping motor.

Claims (1)

[Claims] 1. In an optical switching device that switches the optical path between an input side fiber and a plurality of output side fibers, positioning is provided corresponding to each output side fiber and the output side fiber is inserted and fixed to a halfway position. An optical switching device comprising: a tube; and an insertion/extraction switch that moves an input side fiber toward a desired output side fiber and inserts it into the positioning tube. 2. A circular fixed plate having positioning tubes corresponding to the plurality of output side fibers arranged around its periphery, a rotary plate for rotating the input side fibers, and a rotary plate provided at an intermediate position of the input side fibers; An optical switching device comprising: an optical coupling section consisting of a pair of rod lenses, one of which is provided on the fixed side and the other is provided on the rotary plate.