JP3256341B2 - Multi-core optical fiber alignment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-core optical fiber aligning apparatus, and more particularly to a method for connecting optical fibers of a multi-core optical fiber tape using a multi-core batch fusion splicing apparatus. The present invention relates to a suitable multi-core optical fiber alignment device.

[0002]

2. Description of the Related Art Conventionally, as a device for connecting a multi-core optical fiber tape, a multi-core batch fusion splicing device is known.
In this case, it is necessary to align (align) the optical axes of the multi-core optical fiber and the optical fiber facing the multi-core optical fiber. By the way, as shown in FIG. 7, in the multi-core optical fiber tape 1, a plurality of optical fibers 2 are buried inside the coating material 1a, but the core 2a of each optical fiber 2 is shifted from the center of the clad 2b. Therefore, it is necessary to align the right and left optical fibers 2 to be fused while moving them in a radial direction of a cross section orthogonal to the optical axis (see FIG. 8).

[0003] Conventionally, as a multi-fiber optical fiber alignment device of this type, an individual alignment mechanism (3rd INTER) disclosed by S. AOSHIMA et al.
NATIONAL SYMPOSIUM ON MICRO MACHINE AND HUMAN SCIE
NCE, 1992) is known. In this conventional example (hereinafter referred to as Conventional Example 1), as shown in FIG. 9, each of the inclined members 4 has a set of two elevating members 4 having a 45-degree inclined surface 4a at the upper end.
The piezoelectric elements 5 are connected in series to the lower end of each elevating member 4, and the piezoelectric elements 5 are fixed to the base 6. Each elevating member 4 is inserted through a guide hole 8a of a fixed guide member 8 provided on the mounting base 7 so as to be able to move up and down.

According to the prior art 1, the optical fiber 2 is supported in the V-groove 4b formed by the opposed inclined surfaces 4a of the two lifting members 4, and then the piezoelectric elements 5 are energized to drive them. The vertical movement of each optical fiber 2 in the directions of arrows a, b, c, and d in FIG. 9 is performed by moving the lifting member 4 up and down and adjusting the lifting operation of the two lifting members 4 in each set. Can be.

A second conventional example shown in FIGS. 10 and 11 is known. In the second conventional example, a V-groove member 13 having a plurality of fixed V-grooves 13a is provided at an upper end of a support plate 12 rising from an end of a base 10. Further, the base ends of a plurality of microarms 14 arranged below the V-groove member 13 and arranged in parallel by the pivot 11 above the support plate 12 are pivotally supported.

The micro arm 14 is substantially L-shaped when viewed from the side, and a movable V-groove 15 is formed on the upper surface of the upright end portion 14a. The movable V-groove 15 and the fixed V-groove 13a coincide with each other. The optical fiber 2 is fitted into each V groove.

[0007] Each micro arm 14 is connected to an elevating member 17 to which a piezoelectric element 16 is mounted as a drive source, and the piezoelectric element 16 is disposed on the base 10.
As shown in a plan view in FIG. 11, each piezoelectric element 16 is provided for each of the plurality of microarms 14 so as to be shifted in the front-rear direction. Specifically, of the plurality of micro arms 14 arranged in parallel, the micro arms 14 (shown above in FIG. 11) on one end side and the micro arms 14 on the other end side are sequentially arranged. Are shifted from the distal end to the proximal end side. Thereby, each piezoelectric element 16 (and the lifting member 17)
Are not overlapped with each other, so that the dead space can be reduced and the small space can be efficiently used.

In the second prior art, by driving the piezoelectric element 16, the micro arm 1 is moved through the elevating member 17.
4 with the pivot 11 as a fulcrum, and the movable V
The alignment is performed by moving the optical fiber 2 fitted in the groove 15 two-dimensionally.

[0009]

As the piezoelectric element used as a drive source of the centering device in the first and second conventional examples, a laminated piezoelectric element is used. The element itself is larger than, for example, a bimorph type piezoelectric element, so that the entire apparatus becomes large, and it is difficult to mount the optical fiber in a fusion splicer.

Further, as described in the second conventional example, in order to mount the piezoelectric elements in a small space at a high density, a plurality of piezoelectric elements are arranged at different positions for each micro arm. For this reason, the distance between the fulcrum and the point of force differs for each micro arm supported by a common pivot, and the amount of input movement and the amount of movement at the point of action differ for each micro arm.
The enlargement ratio due to the displacement of the piezoelectric element was different, and the control was complicated unnecessarily.

[0011] The above is because when selecting a piezoelectric element,
This leads to the necessity of considering the different magnification, and the performance of all the piezoelectric elements has not always been efficiently utilized.

In addition, it is very difficult to align the optical fibers at equal intervals due to variations in the processing accuracy of the components of the centering device, and the irregularities are often greater than the displacement of the optical fibers due to the piezoelectric element. However, there is a problem that the adjustment range of the piezoelectric element is exceeded.

An object of the present invention is to provide a multi-core optical fiber alignment device which solves the above-mentioned problems.

[0014]

According to the present invention, each terminal of a multi-core optical fiber in which a plurality of optical fibers are aligned and integrated at substantially equal intervals is individually formed in a two-dimensional plane on a plane substantially perpendicular to the axis of the optical fiber. In a multi-fiber optical fiber centering device that moves and aligns, the moving means of each optical fiber forms a pair for each optical fiber and has a slope facing each other as a contact portion with the optical fiber for each pair. A plurality of pairs of micro-arms forming a V-groove by the facing slopes; and a plurality of pairs of bimorph-type piezoelectric elements for driving the plurality of pairs of micro-arms in a direction perpendicular to the axis and the arrangement direction of the multi-core optical fiber. It is characterized by comprising.

Further, in the present invention, the ends of a plurality of pairs of micro arms are pivotally supported by a support shaft, and the plurality of pairs of bimorph type piezoelectric elements have their longitudinal directions perpendicular to the longitudinal direction of the micro arms. It is provided below the micro arm in such a way that one end is fixed to the base and the other end is fixed to the micro arm, and the length of each bimorph type piezoelectric element is different. And
The length of the bimorph type piezoelectric element whose other end is fixed at the position farthest from the spindle of the micro arm is set to be the longest, and as the position where the other end is fixed moves to the spindle side, it is sequentially. It is characterized in that the length of the bimorph type piezoelectric element is set short.

It is preferable that a plurality of pairs of micro arms are supported by elevating means so as to be individually adjustable via bimorph type piezoelectric elements.

The elevating means may be constituted by a screw hole formed in a base for supporting the micro arm, and an adjusting screw screwed into the screw hole and having a tip abutting on the piezoelectric element.

Further, the micro arm is preferably made of ceramics.

[0019]

According to the present invention, a micro arm made of ceramic or the like having a friction coefficient smaller than that of metal is smoothly driven by a bimorph type piezoelectric element which is smaller than a laminated type, and a multi-core optical fiber is individually separated. To be aligned. The bimorph-type piezoelectric element provided with the disposition position changed for each micro arm adjusts the different magnification of the output portion with respect to the micro arm by changing the length. Further, the height of each micro arm can be easily finely adjusted and moved by the elevating means, and the interval between the multi-core optical fibers having a variation can be finely adjusted.

[0020]

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 explanatory side view of an optical fiber aligning apparatus according to an embodiment, FIG. 2 is an explanatory plan view, and FIG. 3 is an enlarged partial explanatory view of FIG.

Referring to the drawings, in this embodiment,
Two support plates 21 are erected on one side of a base 20 of a predetermined size at a predetermined interval, and a support shaft 22 is supported by each support plate 21. One end 23 of a plurality of micro arms 23 made of ceramics
a is pivoted.

The tip 23b of the micro arm 23 is slightly raised, and a slope 23c is formed on the upper surface thereof. The two micro arms 23 make a pair, and each pair of the two micro arms 23 has a slope 2.
3c are inclined so as to face each other, and a movable V-groove 24 is formed by the facing slope 23c.

A plurality of projections 25 are integrally provided on the lower surface of each of the microarms 23, and a bimorph-type piezoelectric element 26 serving as a driving source is connected to each projection 25. The positions of the projections 25 are shifted from each other for each micro arm 23. Specifically, FIGS. 1 and 2
As can be understood by referring to FIG. 2, as the micro-arm 23 is positioned from the upper side to the lower-side micro arm 23 in the plan view shown in FIG. They are provided at positions shifted by dimensions.

The bimorph type piezoelectric elements 26 are provided in the same number as the micro arms 23 for individually driving the plurality of micro arms 23, and the longitudinal direction of the piezoelectric elements 26 is perpendicular to the longitudinal direction of the micro arms 23. hand,
The piezoelectric elements 26 are arranged in parallel with each other.

The base end of each piezoelectric element 26 is a common base 2
6a. The base 26 a is arranged on one side of the plurality of micro arms 23 and is fixed on one side of the upper surface of the base 20. As shown in FIG. 2, the bimorph type piezoelectric element 26 has a micro arm 2 located on the upper side of FIG.
The piezoelectric element 26 for moving the third element 3 is provided with the longest dimension, and the length of the piezoelectric element 26 is sequentially reduced as it moves to the lower microarm 23.

The tip of a fine adjustment screw 27 is in contact with the lower surface of the piezoelectric element 26 connected to the projection 25 of each micro arm 23. As shown in FIG. 3, the fine adjustment screw 27 is screwed upward from below into a screw hole 28 formed in the base 20, and the fine adjustment screw 27 constitutes a simple elevating means 29. You. Accordingly, each micro arm 23 is movably supported by the elevating means 29 via the piezoelectric element 26, and the height can be individually adjusted by turning the fine adjustment screw 27.

The optical fiber alignment device according to the present embodiment is configured as described above, and one of the multi-core optical fibers 2 (FIG. 5) opposing each movable V-groove 24 formed by a pair of micro arms 23. ), And the other multi-core optical fiber is supported by the same centering device (however, the other side is not shown). Thereafter, the bimorph type piezoelectric element 26 is driven to finely move the inclined surface 23c of the micro arm 23 forming a pair, and the tip of the multi-core optical fiber 2 is two-dimensionally moved to perform centering.

The present inventor prototyped the device of the present embodiment, and encountered various problems associated with the use of a bimorph type piezoelectric element during the trial production process. By solving this by the method described below, the intended purpose was able to be achieved.

First, one problem of the bimorph type piezoelectric element 26 is that of a generated force. That is,
Although the bimorph type piezoelectric element 26 is smaller than the laminated type piezoelectric element, the magnitude of the generated force is several kg for the laminated type piezoelectric element, whereas the bimorph type piezoelectric element 26 is several tens of kg for the bimorph type piezoelectric element.
It is as small as 0 g.

On the other hand, in the conventional optical fiber centering device, metal is used as the material of the micro arm. This metal has a large frictional resistance, and a large force is required for the actuator, and it has been found that it is difficult to move the metal micro arm smoothly by a bimorph type piezoelectric element. Therefore, as a result of studying various materials having low frictional resistance, the inventors focused on ceramics. When a micro arm was fabricated using this ceramic and driven using a bimorph type piezoelectric element, this ceramic micro arm had a significantly lower coefficient of friction than a metal micro arm and generated force was lower. The small bimorph type piezoelectric element was able to move smoothly. For this reason, in this embodiment, the micro arm 23 is made of ceramic.

Next, in order to arrange the bimorph type piezoelectric elements 26 in a small space at a high mounting density, the piezoelectric elements 26 are connected to each other with the position shifted for each micro arm 23 as shown in FIGS. As a result of the difference in the distance between the point of force and the point of action for each microarm 23, adjustment is necessary. Further, as a problem of the bimorph type piezoelectric element itself, the generated force is related to the length of the element itself, and it has been found that by setting the length dimension appropriately, efficient use is possible. .

From these facts, in the present embodiment, the length of the bimorph type piezoelectric element 26 is changed for each micro arm 23, and each micro arm 23 is individually moved using the moving stage 29. The above problem has been solved.

More specifically, the generation characteristics of the bimorph type piezoelectric element 26 are as shown in FIG. 4, and the generated force changes according to the characteristic curve shown in FIG. In addition, on the assumption that the position of the projection 25 is changed for each micro arm 23, and while taking into account the characteristic curve of FIG.
As shown in (1), the length of the bimorph type piezoelectric element 26 for moving each micro arm 23 was changed. As a result, the generated force of the piezoelectric element could be used efficiently.

The fine adjustment of each micro arm 23 can also be performed by the elevating means 29. That is, by turning the fine adjustment screw 27, the micro arm 23 rotates about the support shaft 22 as a fulcrum through the tip thereof, and the slope 23
Since c moves up and down, it is possible to adjust the height of the movable V-groove 24 formed by the opposing slopes 23c, and to perform two-dimensional adjustment of the multi-core optical fiber 2 fitted into this.

The left side of FIG. 5 shows a state in which the micro-adjustment screw 27 of the lifting / lowering means 29 is turned to move each micro arm 23 up or down in the direction of the arrow, thereby adjusting the irregular multi-core optical fiber 2. And the figure on the right shows the state after the adjustment. That is, the multi-core optical fibers 2 having different heights and the like can be aligned at equal intervals by the elevating / lowering means 29, whereby the centering range of the piezoelectric element can be fully utilized. In other words, coarse adjustment in the first stage of the multi-core optical fiber 2 is performed by the lifting / lowering means 29, and fine adjustment of the height of the tip 23b of the micro arm 23 in the second stage is performed by the piezoelectric element 26. It is what you do. By enabling the two-stage adjustment in this way, the centering range of the piezoelectric element 26 can be fully utilized.

The inventor manufactured a multi-core optical fiber aligning apparatus according to the embodiment as described above. As a result, as shown by symbols in FIGS. 1 and 2, the width L ₁ of the centering device can be reduced to about 30 mm, the length L ₂ to about 4 mm, and the height L ₃ to about 10 mm. The fiber alignment device could be downsized.

FIG. 6 shows a multi-core optical fiber alignment device manufactured by the inventor of the present invention and a conventional multi-core optical fiber alignment device, each of which has a different arrangement of a piezoelectric element as a driving source for each micro arm. FIG. 4 is a comparative diagram showing a movement characteristic of an optical fiber due to a displacement. As can be seen from the diagram on the left side of FIG. 6, in the conventional centering device, even if the voltage applied to each piezoelectric element is the same voltage, the operating range is different for each pair of microarms due to different magnifications. The moving range was different in two dimensions for each optical fiber supported by the arm. On the other hand, in this embodiment, the force required for the movement is measured for each micro arm having a different action point,
When the length of each piezoelectric element was designed to be the required length, as can be seen from the diagram on the right side of FIG. 6, the operating range of each core of each optical fiber could be almost the same.

[0039]

As described above, according to the present invention,
It is possible to reduce the size of individual alignment devices for multi-core optical fibers,
Also, fine adjustment for each optical fiber becomes easy. further,
INDUSTRIAL APPLICABILITY The present invention can be applied to a fusion splicing apparatus for a multi-core optical fiber and to alignment for connecting an optical fiber to a light source or an optical waveguide.

[Brief description of the drawings]

FIG. 1 is a side view of a multi-core optical fiber alignment apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is an explanatory side view of elevating means for supporting a micro arm.

FIG. 4 is a characteristic diagram of a generated force of a bimorph type piezoelectric element.

FIG. 5 is an explanatory diagram of an alignment state of a multi-core optical fiber before and after adjustment by an elevating means of a micro arm.

FIG. 6 is a comparison diagram of alignment results of a conventional optical fiber alignment apparatus and an alignment apparatus of the present invention.

FIG. 7 is an end view of the multi-core optical fiber tape.

FIG. 8 is an explanatory diagram showing an optical fiber in which a core is eccentric and an alignment state thereof.

FIG. 9 is a sectional view showing a first example of a conventional optical fiber alignment device.

FIG. 10 is a side view showing a second example of a conventional optical fiber alignment device.

11 is an explanatory side view showing an arrangement position of a piezoelectric element in the centering device of FIG. 10;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Multi-core optical fiber, 20 ... Base, 21 ... Support plate, 2
2: Support shaft, 23: Micro arm, 23c: Slope, 24
... Movable V-groove, 25 projection, 26 piezoelectric element, 27 fine adjustment screw, 29 lifting means.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masahiro Hamada 1st Tayacho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Sumitomo Electric Industries, Ltd. Yokohama Works (72) Inventor Isamu Fujita 1st Tayacho, Sakae-ku, Yokohama-shi, Kanagawa Sumitomo Electric (72) Inventor Shinichi Aoshima 1-6-6 Komachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (56) References JP-A-4-234006 (JP, A) JP Hei 5-93815 (JP, A) Aoshima et al. , Compact Mass Axis Alignment Devices with Piezoelements for Optical Fibers, IEEE Photonics Technology Letters, USA, vol. 4, no. 5, pp. 462-464 (58) Fields surveyed (Int. Cl. ⁷ , DB name) G02B 6/24 G02B 6/36-6/40

Claims (4)

(57) [Claims] 1. A multi-core optical fiber in which a plurality of optical fibers are aligned and integrated at substantially equal intervals, and each end portion is individually moved two-dimensionally on a plane substantially orthogonal to the axis of the optical fiber. In the multi-core optical fiber alignment device, the moving means of each optical fiber is paired for each optical fiber, and each pair has a slope facing each other as a contact portion with the optical fiber for each pair. A plurality of pairs of micro-arms forming a V-groove with the facing slopes, and a plurality of pairs of bimorph-type piezoelectric elements for driving the plurality of pairs of micro-arms in a direction orthogonal to the axis of the multi-core optical fiber and the arrangement direction thereof. consist of an element, the ends of the micro-arms of the plurality of pairs are pivotally supported on a support shaft
In addition, the plurality of pairs of bimorph type piezoelectric elements
Each longitudinal direction is perpendicular to the longitudinal direction of the micro arm.
It is provided below the micro arm in such a way that
One end is fixed to the base, and the other end is
Fixed to the micro arm, the length of each of the bimorph type piezoelectric elements is different,
Forward to the position of the micro arm farthest from the spindle
The length of the bimorph piezoelectric element to which the other end is fixed is
The longest position where the other end is fixed
As it moves to the support shaft side, a bimorph-type piezoelectric element
A centering device for a multi-core optical fiber, wherein a length of a child is set short . 2. The micro arm of each of the plurality of pairs,
Adjustable individually via bimorph type piezoelectric elements
The supporting member is supported by the lifting means.
2. The multi-fiber optical fiber centering device according to 1. 3. The lifting device according to claim 2, wherein the lifting means moves the micro arm.
Multiple screw holes formed in the supporting base and these screw holes
To the adjustment screw whose tip is in contact with the piezoelectric element.
3. The method according to claim 2, wherein
Multi-core optical fiber alignment device. 4. The method according to claim 1, wherein the plurality of pairs of micro arms are ceramic.
2. The device according to claim 1, wherein
An alignment device for a multi-core optical fiber according to any one of claims 1 to 3,
Place.