JP2984451B2 - Optical switch and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber which moves one of a pair of optical fibers in a coupled state in a direction orthogonal to the optical axis and recombines with a third optical fiber juxtaposed with the optical fiber. The present invention relates to a switch and a method for manufacturing the switch.

[0002]

2. Description of the Related Art An optical switch for moving one of a pair of optical fibers in a coupled state and reconnecting the optical fiber to another optical fiber core has to minimize the time during which optical communication is interrupted, such as a submarine cable. Due to demands for use in long-distance communication, high-speed operation and miniaturization are required. Here, it is effective to shorten the moving distance of the optical fiber, that is, the moving stroke, in order to improve the high-speed performance, and to reduce the number of parts in order to reduce the size.

[0003] By the way, to satisfy the above requirements,
An optical fiber fixing section, an optical fiber positioning groove, an optical fiber guide groove, a positioning pin, and a guide pin are provided. By fixing the positioning pin engaged with the optical fiber positioning groove to the positioning pin with an adhesive, two pieces are provided. An optical switch for fixing the above fiber connection member has been proposed (Japanese Patent Laid-Open No. 1-312523).

[0004]

This optical switch has been proposed by the inventor of the present application. However, since the transmission loss of optical fibers has been reduced and the demand of subscriber systems has increased,
Further higher speed and smaller size are required. The present inventor has analyzed the conventional optical switch to satisfy these requirements, and has found the following improvements.

First, since the conventional optical switch has a positioning pin interposed between two fiber connecting members,
The moving stroke was longer, and the switching time was longer.

In addition, since the depth of the positioning groove is smaller than the radius of the positioning pin, the optical switch is forced to exceed the thickness of at least two fiber connecting members.
For this reason, the optical switch has become larger in the thickness direction.

Further, since the positioning groove is formed between the fiber fixing portion and the guide groove, the area for accommodating the optical fiber has been narrowed accordingly.

[0008] Based on the above improvements, an object of the present invention is to achieve high-speed switching in an optical switch and downsizing of the device.

[0009]

To achieve the above object, an optical switch according to the present invention is provided with a first fiber fixing groove in which one optical fiber is embedded and at least both sides of the first fiber fixing groove. A first optical fiber connecting member having a first guide groove, a second fiber fixing groove in which another optical fiber is embedded, and a second guide groove formed on at least both sides of the second fiber fixing groove. A second optical fiber connecting member disposed to face the fiber connecting member; and a first optical fiber connecting member and a second optical fiber connecting member filled in gaps formed on both sides of the first guide groove and the second guide groove.
An adhesive for fixing the optical fiber connecting member, and a guide pin movably inserted into a gap formed by the first guide groove and the second guide groove along a switching direction between one optical fiber and another optical fiber. Wherein the amount of movement of the guide pin is equal to the arrangement interval of one optical fiber and another optical fiber.

The method of manufacturing an optical switch according to the present invention comprises a first step of forming a first groove for fixing an optical fiber and second grooves located on both sides of the first groove in a flat plate, A second step of dividing the flat plate into two in a direction orthogonal to the longitudinal direction of one groove, and fixing the optical fiber in the first groove of one of the divided flat plates and in the first groove of the other flat plate. And a fourth step of laminating one flat plate and the other flat plate and fixing both sides of the second groove.

[0011]

The optical switch according to the present invention has no positioning pin interposed between the first fiber connecting member and the second fiber connecting member. Further, one optical fiber is fixed in the first fiber fixing groove, and the other optical fiber is fixed in the second fiber fixing groove. Therefore, the first fiber connection member and the second fiber connection member are in close contact with each other, and the distance between the optical fibers is reduced.

In the method for manufacturing an optical switch according to the present invention, a plurality of grooves (first and second grooves) are formed in parallel on one flat plate, and the grooves are formed in a direction perpendicular to the longitudinal direction of the grooves. Because it divides into two, for example, if you overlap based on one side of the flat plate,
Each groove faces with high precision.

[0013]

An embodiment of the present invention will be described below with reference to the accompanying drawings. In the description, the same elements will be denoted by the same reference symbols, without redundant description.

First, the structure of the optical switch according to the present embodiment will be described with reference to FIGS. FIG. 1 is a diagram illustrating an optical coupling surface of an optical switch according to an embodiment, and FIG. 2 is an enlarged diagram illustrating an optical coupling surface of the optical switch according to the embodiment without guide pins.

The optical switch according to the present embodiment includes guide pins 6, 7, a first optical fiber connecting member 8, and a second optical fiber connecting member 9 (see FIG. 1).

The first optical fiber connecting member 8 and the second optical fiber connecting member 9 are formed into a united body having the same shape and the same size, and are fixed so as to face each other.
Fiber fixing grooves 8a, 9a and guide grooves 8b, 9b are formed in the first optical fiber connecting member 8 and the second optical fiber connecting member 9, respectively. Since these grooves are all formed in a V-shaped groove, they can be formed only by changing the depth with the same tool. The fiber fixing groove 9a and the guide groove 9b of the second optical fiber connecting member 9 are combined with the fiber fixing groove 8a and the guide groove 8 of the first optical fiber connecting member 8.
It has the same pitch, the same size, and the same shape as b. Therefore, in the superposed state, the fiber fixing grooves 8a, 9a and the guide grooves 8b, 9b accurately coincide with each other, so that gaps a, A having a rectangular cross section are formed (see FIG. 2). ). In the gap a, the optical fibers 10a, 1a supplied from the tape-shaped optical fiber cores 10, 11 are provided.
1a is fixed, and the guide pin 7 is inserted into the gap A.

The fiber fixing grooves 8a and 9a in which the optical fibers 10a and 11a are arranged are formed at least deeper than the outer diameter of the fixed optical fibers 10a and 11a. Therefore, the optical fibers 10a and 11a are positioned in a state where they are completely contained in the groove, and the adhesive is embedded therein, so that no irregularities are generated on the surface. Therefore,
The thickness when the first optical fiber connecting member 8 and the second optical fiber connecting member 9 are superimposed is minimized, and as a result, the optical switch is reduced in size and weight. Therefore, both sides of the guide grooves 8b and 9b are in surface contact,
The gap 16 is filled with the adhesive 16 (see FIG. 2).
Therefore, the bonding area is large and sufficient bonding strength is obtained.

By the way, guide pins 6, 7 are arranged in a gap A formed by the guide grooves 8a, 9a, and when switching, the guide pins 6, 7 collide with the guide groove 8b or the guide groove 9b. Force is generated. But,
Both sides of the portion to which the impact force is applied are firmly fixed by the adhesive 16 by surface contact, and the optical switch according to this embodiment is lightweight as described above, so that the impact resistance is synergistic. Has been strengthened.

Next, the overall configuration of the optical switch according to the present embodiment will be described with reference to FIG. FIG. 3 is a perspective view illustrating a use state of the optical switch according to the embodiment.

The first optical fiber connecting member 8 is connected to a tape-shaped optical fiber core 10, and the second optical fiber connecting member 9 is connected to a tape-shaped optical fiber core 11. Guide pins 6 and 7 are inserted into the gaps A and A, respectively. In order to fix these guide pins 6 and 7,
A pair of block members 14 is provided at the front and rear portions of the integrated first optical fiber connecting member 8 and second optical fiber connecting member 9.
15 are placed. Two V-shaped grooves 14a and 14b are formed in the block body 14 in parallel, and a tape-shaped optical fiber core 17 is fixed between the two V-shaped grooves 14a and 14b. This tape-shaped optical fiber core 17 is
They are arranged in the optical axis direction along the above-mentioned tape-shaped optical fiber core wire 11, and the respective optical coupling end faces face each other. Similarly, the block body 15 has two V-shaped grooves 15a,
15b are formed in parallel, and two V-shaped grooves 15a,
The tape-shaped optical fiber core wires 10 and 11 are placed in a stacked state between the wires 15b. Guide pins 6 and 7 described above
Are engaged with the V-shaped grooves 14a, 15a and 14b, 15b, and are fixed by an adhesive and a fixing jig (not shown).

Next, the operation of the above-described optical switch will be described. The guide pins 6 and 7 are provided with guide grooves 8b and 9
After being inserted into the gap A formed by b, the optical switch is fixed to the blocks 14, 15, and the optical switch is driven by a solenoid (not shown) or the like. When the guide pins 6 and 7 are held in contact with the upper portion of the gap A (see FIG. 1), the optical fiber 10a supplied from the tape-shaped optical fiber 10 and the optical fiber 10 supplied from the tape-shaped optical fiber 17 are supplied. Optical fibers are optically coupled to each other. However, when the optical switch is driven by the solenoid and the guide pins 6 and 7 are held in contact with the lower part of the gap A (FIG. 2).
), The optical fiber 11a supplied from the tape-shaped optical fiber 11 and the optical fiber supplied from the tape-shaped optical fiber 17 are optically coupled to each other.

In this case, a conventional optical switch (Japanese Unexamined Patent Publication No.
Since the movement stroke L is smaller than that in the example 312523), the tape-shaped optical fiber core 17 can be switched from the tape-shaped optical fiber core 10 to the tape-shaped optical fiber core 11 in a short time.

At the same time, the thickness of the optical switch itself is reduced, so that the entire device becomes smaller and lighter. further,
With the increase in communication demand, the number of cores of the optical cable is steadily increasing. However, according to the optical switch according to the present embodiment, all between the guide grooves can be used as an optical fiber fixing portion, and the number of cores increases. It is easy.

Further, in the optical switch according to this embodiment,
Because of the light weight, the impact force is small, and the both sides of the position where the impact force is generated are firmly fixed by adhesive with surface contact, so the impact resistance is high and the adhesive peels off Hateful. Therefore, long-term reliability is improved.

The guide pins 6 and 7 are provided with guide grooves 8b,
It has been confirmed that even when the guide grooves 8b and 9b are slightly misaligned in the lateral position (the misalignment in the direction in which the optical fibers are arranged) when they come into contact with 9b, the characteristics are not affected.
There is no substantial problem due to the absence of the positioning groove and the positioning pin.

Next, an example of a method for manufacturing the above-described optical switch will be described with reference to FIGS. 4 and 5 are process diagrams illustrating a method for manufacturing the optical switch according to the embodiment.

First, in a first step, a first V-shaped groove (first groove) 19a is formed in a plane portion of the flat plate 19 to form a first groove and a second groove in the flat plate 19 made of silicon single crystal or the like. Formed on both sides of the first V-shaped groove 19a.
A groove 19b is formed (FIG. 4A). Each of these V-shaped grooves 19a and 19b is sequentially formed in parallel by a diamond blade 20 having a V-shaped tip based on a measured value from the reference surface of the flat plate 19. Note that these V
The forming order of the grooves may be reversed.

In the second step, the flat plate 1 on which the V-groove is formed
9 two in the direction orthogonal to the longitudinal direction (19A, 19B)
(FIG. 2B). Next, the optical fibers 10a and 11a supplied from the tape-shaped optical fibers 10 and 11 are arranged at the bottom of the first V-shaped groove 19a of each of the two divided flat plates 19A and 19B, and the adhesive is applied. (FIG. 5C). As described above, since the V-shaped groove 19a is deeper than the outer diameter of the optical fibers 10a and 11a, no irregularities occur on the surface. Next, the V-shaped grooves 19a, 1b are superimposed along the reference planes of the divided flat plates 19A, 19B.
9b is matched. In this case, since the V-shaped grooves 19a and 19b are accurately positioned with respect to the reference plane with respect to the flat plate 19, a perfect rectangular gap A is formed by overlapping the two flat plates 19A and 19B. ((D) in the same figure). Finally, the guide pins 6 and 7 are inserted into the gap A and fixed with the block body.

As described above, according to the manufacturing method of this embodiment, since no positioning groove is formed, there is no work associated with the formation of the groove and the work of engaging the positioning pin in the groove, so that the number of steps is reduced, and workability is reduced. Will be better.

Finally, experimental results on the positioning accuracy and the coupling strength of the optical switch according to the present embodiment and the conventional optical switch will be described.

In the experiment on the positioning accuracy, 20 optical switches according to the present embodiment having no positioning pin and 20 conventional optical switches having the positioning pin were prototyped.
The switching loss value for a pair of optical fibers arranged side by side was measured in order. As a result, according to the optical switch according to the present embodiment, the average switching loss value when connected to one optical fiber is 0.32 dB, and the average switching loss value when switched to the other optical fiber is 0.40 dB. Was. On the other hand, according to the conventional optical switch, the average switching loss value when connected to one optical fiber was 0.38 dB, and the average switching loss value when switched to the other optical fiber was 0.33 dB.

In the experiment on the bonding strength, the wall thickness was 1.
Using a 1 mm silicon chip, an optical switch according to the present embodiment having no positioning pin and a conventional optical switch having a positioning pin are manufactured. Each guide groove has an outer diameter of 0.7 mm and a length of 11.0 mm. One end of the test pin was inserted into the guide groove by 5.0 mm, and a load was applied to the other end of the test pin to measure the strength at which the guide groove was broken. As a result, the breaking load of the optical switch according to the present example was 1.58 kg, whereas the breaking load of the conventional optical switch was 0.55 kg.

From the above experiments, when comparing the optical switch according to the present embodiment having no positioning pin with the conventional optical switch having the positioning pin, it is found that there is no practical problem at least in terms of positioning accuracy and coupling strength. confirmed.

It should be noted that the present invention is not limited to the above embodiment, and various embodiments are possible without departing from the spirit of the invention. Therefore, in the above embodiment, for convenience of explanation, the optical fiber connecting member is a flat plate, and the groove is V.
Although an adhesive is used as an example as a shape and a fixing means, the present invention is not limited thereto. For example, as a method of fixing the optical fiber connecting member, in addition to the adhesive fixing,
An intermolecular bonding method may be used in which the bonding surface of the silicon member is activated and is fixed by heating the silicon member at a high temperature. Further, it may be fixed by a metal holding member such as a clip.

[0035]

As described above, according to the present invention, by adopting a structure in which the first optical fiber connecting member and the second optical fiber connecting member are in close contact with each other, high-speed switching and miniaturization of the optical switch are achieved. Can be.

Further, since the number of parts is reduced, the weight is reduced as a whole, and accordingly, the impact force generated at every switching can be reduced.

Further, since both sides of the location where the impact occurs are fixed by surface contact, the fixing force of the two optical fiber connecting members is strengthened. Therefore, the shock resistance against the shock caused by the movement of the guide groove is further improved, and the long-term reliability of the optical switch is improved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an optical coupling surface of an optical switch according to an embodiment of the present invention.

FIG. 2 is an enlarged view showing an optical coupling surface of the optical switch according to the embodiment of the present invention without a guide pin;

FIG. 3 is a perspective view showing a use state of the optical switch according to the embodiment of the present invention.

FIG. 4 is a perspective view showing manufacturing steps (a), (b), and (c) of the optical switch according to the embodiment of the present invention.

FIGS. 5A and 5B are perspective views showing manufacturing steps (d) and (e) of the optical switch according to the embodiment of the present invention.

[Explanation of symbols]

6, 7: guide pin, 8: first optical fiber connecting member, 9
... Second optical fiber connecting member, 10, 11, 17 ... Tape-shaped optical fiber core wire, 14, 15 ... Block body, 16 ... Adhesive, 19 ... Flat plate, 20 ... Diamond blade.

Continuing from the front page (72) Kazuo Ikegaya 1-chome, Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Sumitomo Electric Industries, Ltd. Yokohama Works (72) Inventor Masatoshi Shimizu 1-1-6 Uchisaiwai-cho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation In-company (72) Inventor Hideo Kobayashi 1-6-1, Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (58) Fields investigated (Int.Cl. ⁶ , DB name) G02B 26/08

Claims (4)

(57) [Claims] 1. A first optical fiber connecting member having a first fiber fixing groove in which one optical fiber is embedded, and first guide grooves formed on at least both sides of the first fiber fixing groove, and another light A second optical fiber having a second fiber fixing groove for burying a fiber, and a second guide groove formed on at least both sides of the second fiber fixing groove, and arranged in a state facing the first optical fiber connecting member; A connecting member; an adhesive member filled in gaps formed on both sides of the first guide groove and the second guide groove to fix the first optical fiber connecting member and the second optical fiber connecting member; A guide pin movably inserted along a switching direction between the one optical fiber and the other optical fiber in a gap formed by the guide groove and the second guide groove, Optical switch movement amount of the serial guide pin, characterized in that equal to the arrangement interval of the one optical fiber and the other optical fiber. 2. The first fiber fixing groove and the second fiber fixing groove.
The fiber fixing groove is a V-groove formed so that a part of the optical fiber does not protrude from surfaces of the first optical fiber connecting member and the second optical fiber connecting member. An optical switch as described. 3. A first step of forming a first groove for fixing an optical fiber and second grooves located on both sides of the first groove in a flat plate, and in a direction orthogonal to the longitudinal direction of the first groove. A second step of dividing the flat plate into two, a third step of fixing the optical fiber in the first groove of one of the divided flat plates, and fixing the optical fiber in the first groove of the other flat plate; And a fourth step of laminating the one flat plate and the other flat plate and fixing both sides of the second groove. 4. The method according to claim 3, wherein the first groove is a V-groove formed so that a part of the optical fiber does not protrude from the surface of the flat plate. .