JPH0447283B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The connection of polarization-controlled optical fibers is mainly performed using the 4a
As shown in Fig. 4b, there are three types of stress applying parts 18: matching, 90° different, and 45° different (for example, for making a depolarizer) (16 is a core).

Therefore, when connecting the constant polarization optical fiber, alignment in the θ direction is required in addition to alignment in the x and y directions (see arrows) and spacing adjustment in the z direction.

The present invention relates to a fusion splicing apparatus for constant polarization optical fibers, and particularly to the above-mentioned alignment mechanism performed before fusion splicing.

[Prior art] The one shown in Figure 5a has been proposed (Japanese Patent Application
61-115901), in the figure, 10 is the entire polarization optical fiber, 12 is the coated portion, and 14 is the bare fiber.

20 is a V-groove block, which is movable in the x and y directions. A bare fiber 14 is placed on top of it and held by a fiber clamp 22.

Reference numeral 24 denotes a z-axis stand, on which the covering portion 12 is placed and gripped by a covering clamp 26. The z-axis stand 24 can swing around the pin 28 in the direction of arrow 30, and the upper surface of the z-axis stand 24 moves in the z direction accordingly.

A bracket 32 rotatably supports the cylindrical members 34A and 34B. Cylindrical member 3 on the right side in Figure 5a
A dial 36 is directly connected to 4A.

Two arms 38 protrude from the cylindrical members 34A and 34B, and a θ clamp 40 is provided at the tip thereof (FIG. 5b).

The θ clamp 40 has a V groove 42 (5th b
figure). When the two arms 38 are brought close to each other,
The covered portion 12 moves on the guide plate 44 to form the V-groove 4.
2.

When the dial 36 is rotated in this state, the optical fiber 10 is rotated in the θ direction.

A gear 46 is directly connected to the left cylindrical member 34B,
It is rotated by a motor 48.

On the left side, the z-axis stand 24 and the bracket 32 are attached to one block (not shown), and the block is movable in the z-axis direction by a motor.

50 is an abutment rod, and a mirror 52 is provided at the upper end of the abutment rod. 54 is a microscope.

- Its function: (1) The optical fiber 10 is set and gripped by the fiber clamp 22, coating clamp 26, and θ clamp 40.

(2) Observe the end face image of the optical fiber 10 reflected on the mirror 52 with the microscope 54, and adjust the rough alignment in the θ direction so that the position of the stress applying part 18 is in the constant relationship shown in FIGS. 4a to 4c above. conduct.

(3) Align in the x and y directions.

(4) Perform fine centering in the θ direction.

Note that when aligning in the θ direction, the grip by the covering clamp 26 is released so that the optical fiber 10 can rotate without resistance.

(5) Align in the x and y directions again (if the core is eccentric, θ alignment will cause the core axis to shift).

(6) Then fusion splice.

Note that the above alignments (3) to (5) are performed by a so-called far end monitor.

[Problems to be Solved by the Invention] As described above, since there are three clamps: the fiber clamp 22, the covering clamp 26, and the θ clamp 40, (1) the distance between the fiber clamp 22 and the θ clamp 40 becomes long; , θ rotation, the optical fiber 10 is likely to be twisted.

Therefore, ultra-fine adjustment is required for accurate θ alignment. Optical fiber 1 for direction movement
0 The movement of the tip does not follow.

Therefore, the optical fiber 10 may move back and forth in the z direction during θ alignment, or the z direction of the optical fiber 10 may shift during fusion.
The direction movement may not be as per the settings.
The connection becomes unstable.

(3) As described above, a mechanism is required to release the covering clamp 26 when the optical fiber 10 is rotated by θ, and the operation is also complicated.

[Means for Solving the Problems] As shown in FIG.
(2) The above-mentioned problem is solved by making the θ clamp 40 also serve as the covering clamp 26.

[Embodiment] (Figs. 1a to 1c) A bracket 32 is mounted on the shaft stand 24 (supported by a pin 28 and swingable in the direction of the arrow 30).

As in the above case, a bracket 32 supports the cylindrical members 34A, B, and a dial 36 is directly connected to the cylindrical member 34A on the right side in FIG. 1a.

Arms 56 protrude from the cylindrical members 34A and 34B. The arm 56 has, for example, a semicircular cross section (FIGS. 1b and 1c), and has a θ clamp 58 at its tip that also serves as a conventional covering clamp.

The structure of the θ clamp 58 which also serves as a covering clamp is as follows, for example. That is, as shown in FIG. 1b, the lid 60 is attached to the arm 56 by a hinge 62, the closed state is ensured by, for example, a magnet 64, and the presser foot 66 is pressed against the covered portion 12 by a spring 68.

Incidentally, as shown in FIG. 1c, a groove 70 is provided in the bracket 32, and a groove 72 is provided in the cylindrical member 34A and the dial 36, so that the optical fiber 10 can be set and taken out.

Reference numeral 74 denotes a motor, which moves the spindle 76 back and forth and causes the z-axis base 24 to swing.

Reference numeral 78 denotes a return spring whose force is set to be the sum of the screening force after fusion and the component in the z-axis direction of the weight of the entire component placed on the z-axis stand 24.

80 on the left side in Figure 1a is the fine adjustment dial,
The reduction gear 82 enables fine adjustment of the θ axis.

83 is a bracket.

Other than the above, this is the same as the conventional case shown in FIG. 5a.

"Effect" It is almost the same as the conventional case above, but just to be sure, it is as follows.

(1) The optical fiber 10 is set and the θ clamp 5 serves as both the fiber clamp 22 and the coating clamp.
Grip with 8.

(2) Observe the end face image of the optical fiber 10 reflected on the mirror 52 with the microscope 54, and use the dial 36 to adjust the angle of θ.
Performs coarse centering in the direction.

(3) Align in the x and y directions.

(4) Perform fine adjustment in the θ direction using 80 while watching the power meter.

Note that when aligning in the θ direction, there is no resistance from the cover clamp 26, so there is no problem of releasing the conventional grip.

(5) Perform alignment in the x and y directions again.

(6) Then fusion splice.

[Other Embodiments] Two modifications of the portions related to the θ clamp that also serves as the above-mentioned covering clamp will be described below.

[Part 1] (Figures 2a to 2d) Figure 2a shows the right side clamp part, and its B,
The cross sections of C and D are shown in Fig. 2b, Fig. 2c, and Fig. 2d, respectively.

A bracket 32 mounted on the z-axis stand 24 rotatably supports the cylindrical member 34A. From the holder 83 integrated with the cylindrical member 34A, the arm 8
4 stands out.

This arm 84 has a shape in which an elongated cylindrical body is divided into three parts, and the distal end thereof becomes thick in a trundle shape (Fig. 2b). Each of these has a fan-shaped presser foot 86 on its inner surface (FIG. 2d), and its tip portion grips the coated portion 12 of the optical fiber 10.

A sheath guide 88 is fixed to one of the pressers 86 and has a groove 89 into which the optical fiber 10 is inserted. This serves to guide the optical fiber 10 so that it is held in the correct position.

90 is a cylindrical slider, which has a flange 92 at its rear end (see arrows for front and back). This is slidably placed over the arm 84, and is biased forward by a spring 94.

96 is a locking claw, which is pinned to the holder 83.

98 is a spring, 100 is a push button, 102 is a backlash remover.

- Its operation Figures 2a and 2b show a state in which the claw 96 is engaged with the flange 92 and the slider 90 is at the rear.

When the push button 100 is pressed, the pawl 96 is removed from the flange 92 and the slider 90 is moved forward by the force of the spring 94.

Then, the arm 84 is compressed inward, and the presser foot 86 grips the coated portion 12 of the optical fiber 10.

When the holder 83 is rotated in this state, the optical fiber 10 is rotated in the θ direction.

Moreover, when the z-axis table 24 is rocked, the optical fiber 10 moves in the z direction.

With this mechanism, fibers of any coated diameter can be clamped at the center (without moving the guide plate 118 as in the next example).

[Part 2] (Figures 3a to 3d) Two arms 104 protrude with their rear ends attached to the cylindrical member 34A by pins 106.

A gear 108 opens and closes the two arms 104 at equal angles.

A cam 110 is used to open the space between the two arms 104. The two arms 104 are always urged in the closing direction by a tension spring 105.

112 is a lever for rotating the cam 110;

A presser foot 114 is provided at the tip of each arm 104.
The presser foot 114 has a V-groove 116 (FIG. 3c).

Reference numeral 118 denotes a guide plate, which has a long and narrow plate shape. It rests on the arm 104 and is translated in the x direction by the action of the elongated hole 120 and the pin 122 (FIG. 3b).

The surface of the guide plate 118 has grooves 124 in the z direction.
(Figure 3c).

〓The effect: When the optical fiber 10 is thick (for example, 0.9 mmφ)
supports the optical fiber 10 at the bottom of the groove 124, as shown in FIG. 3c.

In addition, when the optical fiber 10 used is thin (for example, 0.25 mmφ), the guide plate 118 is moved to the left in the same figure as shown in FIG.
Use it so that the optical fiber 10 is placed on top of it.

In the above manner, when the arms 104 are closed by the cam 110, the coated portion 12 of the optical fiber 10 is held in the V-groove 116.

Note that the V-groove 116 has a very shallow V shape and is designed to be able to grip both thick and thin optical fibers.

[Effects of the invention] Since the θ clamp 40 is mounted on the z-axis stand 24 and also serves as the coating clamp 26, (1) it becomes possible to position the θ clamp 40 near the fiber clamp 22; .

Therefore, twisting of the optical fiber during θ-axis alignment is eliminated, and the ability to follow the actual rotation of the optical fiber with respect to the rotation of the θ-axis is improved.

It also eliminates the difficulty of adjusting the device to avoid twisting the optical fiber.

(2) Since the distance between the fiber clamp 22 and the θ clamp 40 is short, there is no bending of the covered portion 12 when the optical fiber is gripped and moved in the z direction.

Therefore, the movement of the tip of the optical fiber can better follow the movement of the z-axis table 24 in the z-axis direction, and the rigidity is small (in the future, the fiber diameter and jacket diameter will be reduced as the fiber will be wound with a small diameter using a gyroscope, etc.). (as jacket materials become softer) fibers can also be connected.

As a result, the optical fiber cannot move in and out in the z-axis direction during θ-axis alignment, and accurate θ-axis alignment becomes possible. Furthermore, the movement of the optical fiber in the z-axis direction during discharge is stabilized, allowing stable connection.

(3) The conventional cover clamp 26 release mechanism is eliminated, making the operation easier and mechanically simplified.

[Brief explanation of drawings]

FIG. 1a is an explanatory diagram of an embodiment of the present invention, FIGS. 1b and 1c are explanatory diagrams of cross sections B and C in FIG. 1a, and FIG. 2a is an explanatory diagram of another embodiment of the present invention.
Figures 2b, 2c, and 2d are explanatory diagrams of cross sections B, C, and D of Figure 2a, Figure 3a is an explanatory diagram of yet another embodiment of the present invention, and Figures 3b and 3.
Figures c and 3d are explanatory diagrams of cross sections B, C, and D in Figure 3a, and Figures 4a, 4b, and 4c are
FIG. 5A is an explanatory diagram of a method of connecting polarized optical fibers, FIG. 5A is an explanatory diagram of a conventional technique, and FIG. 5B is an explanatory diagram of cross section B in FIG. 5A. 10... Optical fiber, 12... Covering portion, 14
... Bare fiber, 16 ... Core, 18 ... Stress applying part, 20 ... V groove stand, 22 ... Fiber clamp, 24 ... Z-axis stand, 26 ... Covered clamp, 2
8...Pin, 30...Arrow, 31...Set plate, 32...Bracket, 34A, B...Cylindrical member, 36...Dial, 38...Arm, 40
...θ clamp, 42...V groove, 44...guide plate, 46...gear, 48...motor, 50...
Abutment rod, 52...Mirror, 54...Microscope, 5
6... Arm, 58... θ clamp that also serves as a covering clamp, 60... Lid, 62... Hinge, 64
... Magnet, 66 ... Presser foot, 68 ... Spring, 70 ...
...Groove, 72...Groove, 74...Motor, 76...
Spindle, 78...Spring, 80...Fine adjustment dial, 82...Reduction gear, 83...Holder, 84...
... Arm, 86 ... Presser, 88 ... Sheath guide, 90 ... Slider, 92 ... Flange, 94
...Spring, 96...Claw, 98...Spring, 100...
...Push button, 102...Backlash remover nut, 10
4... Arm, 106... Pin, 108... Gear, 110... Cam, 112... Lever, 114
... Presser foot, 116 ... V groove, 118 ... Guide plate, 120 ... Long hole, 122 ... Pin, 124 ...
…groove.

Claims (1)

[Claims] 1. A fiber clamp that grips a bare fiber on a V-groove base adjustable in the x and y directions and keeps it slidable in the z direction; and a fiber clamp that holds the bare fiber on a V-groove base that is adjustable in the x and y directions; In a fusion splicing device for a constant polarization optical fiber, the θ clamp is equipped with a coating clamp that grips the coating portion; and a θ clamp that can rotate in the θ direction while holding the coating portion; the θ clamp is mounted on the z-axis table. , and also serves as the covering clamp.