JP2001296486A - Matrix optical switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a matrix optical switch for micromachine having a good response and long service life. SOLUTION: The matrix optical switch consists of a package 32 formed of a top cover 11a having a plurality of notches for forming an input port or an output port and a main body part 12a while holding the outer peripheral surface of an optical fiber end at a peripheral part, and a reflecting mechanism 16. The top cover 11a, main body part 12a, peripheral edge of the end of input side optical fibers 20a-20d, and peripheral edge of the end of output side optical fibers 22a-22h are sealed by a sealing compound 14, and thus a package 32 whose inside is sealed under vacuum is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a matrix optical switch, and more particularly to a matrix optical switch used for a micromachine.

[0002]

2. Description of the Related Art Heretofore, a reflection mirror has been provided at each of intersections between input optical paths of a plurality of rows and output optical paths of a plurality of columns, and the position of the intersection with an output optical path selected based on a control signal from a control unit has been provided. There is known a matrix optical switch having a configuration in which light from an input optical path is reflected by a reflecting mirror and guided to a selected output optical path.

For example, in Japanese Patent Laid-Open No. 5-134195, as shown in FIG. 5, a reflection mirror 52 which is moved up and down while maintaining a reflection angle by an actuator 50 is located at an intersection of an input optical path and an output optical path. A matrix optical switch provided corresponding to all is disclosed. In this matrix optical switch, the reflection mirror 52 is usually
Only the movable reflection mirror 52 at the selected position (in FIG. 5, the reflection mirror 52 moved up and down by the actuator at the position shown by oblique lines) is inserted into the optical path by the actuator 50. Thereby, the laser beam passing through the input optical path is reflected and guided to the output optical path.

Also, Electrostatic Micro Torsion Mirr
ors for an Optical Switch Matrix (JOURNAL OF MICROE
LECTROMECANICAL SYSTEMS, VOL.5, NO4, p231〜p237, DECEM
As shown in FIG. 6, a matrix optical switch having a configuration in which a flat mirror 56 axially supported above a light path by a thin polysilicon torsion bar 54 is attracted upward by electrostatic force and retreated from the light path is shown in FIG. Proposed.

[0005] In any of the matrix optical switches, a laser beam from an input-side optical fiber is converted into a parallel beam by an input-side coupling lens and is incident on an input optical path. The laser beam is reflected by a reflection mirror at the intersection of one output optical path selected from the output optical paths of the above and guided to the output optical path, and the laser beam passing through the output optical path is coupled to the output side at the output end of the output optical path. And converged by a lens for input to the optical fiber on the output side.

In recent years, with the development of optical micromachine technology, the importance of matrix optical switches used in optical micromachine technology has been increasing, and optical switches for optical micromachine technology shown in FIG. 6 have been proposed.

[0007]

However, the matrix optical switch used in the optical micromachine technology is very small in size as compared with the matrix optical switch of the conventional configuration, so that the response is likely to be deteriorated, and the light reflected from the reflecting mirror is difficult. There is a problem that the reflectance is easily lowered and the life is short.

[0008] Therefore, an object of the present invention is to provide a matrix optical switch which has a good response response, a light reflectance of a reflecting mirror is hardly reduced, and a long life.

[0009]

In order to achieve the above object, according to the present invention, at least one input port for guiding an externally input laser beam to an input optical path;
A selective reflection means for reflecting or passing a laser beam propagating through the input optical path to guide it to an output optical path; and an output port provided at an end of the output optical path through which the laser beam reflected or passed by the selective reflection means propagates. And wherein at least the input optical path, the selective reflection means, and the output optical path are provided inside a closed casing with a vacuum inside the casing.

[0010] That is, the present inventors have discovered the following three factors as a cause of a poor response response and a shortened life of a matrix optical switch. (1) Adhesion of water vapor in the atmosphere (2) Influence of foreign matter such as dust and dust in the air (3) Effect of air resistance First, the factor (1) will be described. If water vapor in the atmosphere adheres to the reflecting mirror and the portion supporting the reflecting mirror and forms dew, the reflecting mirror and the portion supporting the reflecting mirror are attracted by the surface tension of the condensed water. The mirror cannot be driven smoothly,
Response Response deteriorates.

Further, the reflecting mirror is oxidized by oxygen and water in the atmosphere and dewed water, so that the reflecting mirror is oxidized and corroded.
The corroded portion changes the optical performance of the reflecting mirror and causes stray light.

In particular, in a matrix optical switch of a micromachine, since the size of the reflection mirror is very small, if the reflection mirror is oxidized or corroded even in a part, the optical characteristics of the reflection mirror are significantly deteriorated, which is a serious problem. The deterioration of the optical characteristics of the reflection mirror also causes the life of the matrix optical switch to be shortened.

Next, the factor (2) will be described. When foreign matter such as dust or dust floating in the air enters the matrix optical switch, the laser beam propagating in the optical path is scattered, and the light intensity of the laser beam guided to the output port decreases. In addition, the generated stray light may enter another output port and cause a malfunction.

In particular, this problem is caused by a minute amount of dust because the size of the matrix optical switch for micromachines is small and the size of the dust is relatively large compared to the size of the matrix optical switch. However, this also seriously affects the optical characteristics of the matrix optical switch and is serious.

Further, there is a possibility that dust or dirt may enter between the reflection mirror and the portion supporting the reflection mirror and deteriorate the driving performance of the reflection mirror.

Further, the factor (3) will be described. Since the matrix optical switch for a micromachine is minute, it receives a large air resistance. Due to this air resistance, the load applied to the reflection mirror increases, driving performance decreases, and response response deteriorates.

As described above, in the first aspect of the present invention, at least the input optical path, the selective reflection means, and the output optical path are provided in a sealed housing having a vacuum inside, and the input optical path, the selective reflection means, and the output optical path are provided. Is shielded from the external environment, thereby making it less susceptible to the external environment.

That is, since there is no danger that foreign matter such as water vapor, dust and dirt in the atmosphere will enter the housing, the water vapor adheres to the selective reflection means to constitute the selective reflection means (for example, a reflection mirror). It is possible to prevent the reflector from being oxidized and corroded, deteriorating the optical performance, and preventing the reflector from adhering to the selective reflector and hindering the drive of the selective reflector. for that reason,
Not only can the matrix optical switch always maintain stable optical characteristics, but also good driving performance can be maintained for a long period of time.

Further, since the inside of the housing is maintained in a vacuum state, the selective reflection means is not affected by the air resistance, so that the driving performance of the selective reflection means is not reduced by the air resistance, and the response response is reduced. And a long-life matrix optical switch.

The inside of the housing is evacuated by a method of assembling a matrix optical switch in a vacuum chamber. After pulling, it can be performed by a method of closing the flow passage.

The selective reflection means for guiding the laser beam propagating in the input optical path to the output optical path includes a reflecting surface disposed on the input optical path to reflect the laser beam and change the propagation direction of the laser beam to change the output optical path. Alternatively, a laser beam may be withdrawn from the input optical path by retracting the reflection surface to pass the laser beam, and may be guided to the output optical path without changing the propagation direction of the laser beam.
Further, when a plurality of selective reflection means are provided for one input optical path, the plurality of selective reflection means is such that the selected one of the selective reflection means reflects the laser beam and the other selective reflection means. The reflection means is controlled to retreat from the input optical path and guide the laser beam to the output optical path by passing the laser beam.

The selective reflection means is provided at a position retracted from the optical path so as not to intersect with the propagation direction of the laser light, and is provided rotatably supported by the rotation shaft member. The laser beam may be reflected such that the laser beam input from the corresponding input optical path is guided to the corresponding output optical path. The rotating shaft member can be provided so as to be parallel to the optical path above the optical path or to be perpendicular to the optical path. The rotating shaft member may be provided at a position retracted from the optical path on the side of the optical path so as to be parallel to the optical path or to be perpendicular to the optical path.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIG.
The matrix optical switch 10 for a micromachine according to the present embodiment shows only a package 32a formed by an upper lid 11a and a main body 12a, and a reflection mechanism 16 (in FIG. 1, a reflection mirror (that is, a reflection surface of the reflection mechanism 16)). ). Note that the package 32a corresponds to the housing of the present invention, and the reflection mechanism 16 corresponds to the selective reflection means of the present invention.

A plurality of notches for forming an input port or an output port by sandwiching the outer peripheral surface of the end of the optical fiber are formed in the peripheral edge of each of the upper lid 11a and the main body 12a constituting the package 32a. ing.

Due to these notches, an opening is formed in the side surface of the package 32a when the upper lid 11a is placed on the main body 12a. This opening allows the input side optical fiber 20
a to 20d outer peripheral surface or output side optical fiber 22a
The input optical fibers 20a to 20d and the output optical fibers 22a to 22h are integrated with the matrix optical switch while the outer peripheral surfaces of the ends of the optical fibers 22a to 22h are held.

The outer peripheral edge of the end of the upper lid 11a, the main body 12a, the end of the input side optical fiber 20a to 20d and the outer peripheral edge of the end of the output side optical fiber 22a to 22h are sealed with a sealant 14.
To form a sealed package 32a.

The reflection mechanism 16 is provided above the optical path at all intersections of the plurality of input optical paths and the plurality of output optical paths. Normally, a reflecting surface is disposed at a position retracted from the optical path to pass the laser beam. However, when selected by a control unit (not shown), a reflection surface is arranged in the optical path of the laser beam to reflect the laser beam, change the optical path, and guide it to the corresponding output port. Although not shown, the control unit controls the state of changing the optical path of the matrix optical switch. By selecting the reflection mechanism 16 at a specific position and disposing the reflection mirror (reflection surface) on the optical path, the propagation of the laser beam is performed. The direction has changed.

As described above, the upper lid 11a, the main body 12a,
Since the outer peripheral edges of the ends of the input-side optical fibers 20a to 20d and the outer peripheral edges of the ends of the output-side optical fibers 22a to 22h are sealed by the sealant 14, water vapor, dust and dirt in the atmosphere are reflected by the reflection mechanism 16 Does not adhere to Therefore,
A good response can always be obtained, oxidation and corrosion of the reflection surface of the reflection mechanism 16 can be suppressed, and the life of the reflection surface can be extended.

Also, dust and dirt in the atmosphere are removed from the package 32a.
Of the laser beam propagating in the package 32a can be prevented from being scattered.

The matrix optical switch 10 for a micromachine is, for example, 1.0 × 1
By sealed assembled 0 ^-3 was vacuum degree than 1.0Pa or less Pa in the chamber, the package 3
The degree of vacuum in 2a is, for example, 1.0 × 10 ⁻³ Pa or more.
It is about 0 Pa or less.

When the performance of the matrix optical switch with this embodiment was confirmed, both the insertion loss and the extinction ratio were ± 1 d.
It was within B or so. This matrix optical switch is about 4
After the use for a year, the insertion loss and the extinction ratio were measured again. Both were within ± 1 dB, and the response speed of the switch hardly changed.

On the other hand, as a comparative example, a conventional matrix optical switch configured so that air can enter and exit the package without hermetically closing the package has an insertion loss of 1%.
The extinction ratio was about 60 dB. further,
When the insertion loss and the extinction ratio were measured again using the conventional matrix optical switch for two years, the insertion loss increased to 20 dB and the extinction ratio also decreased to about 30 dB due to the corrosion and fogging of the reflection mirror. Was.

In a conventional matrix optical switch,
Although the response speed of the switch is limited to about 5 ms (200 Hz), the response speed of about 3.3 ms (300 Hz) can be realized in the matrix optical switch of the present embodiment.

In the above-described matrix optical switch, since the upper lid 11a and the main body 12a have a substantially symmetrical shape, notches are provided in both the upper lid 11a and the main body 12a, so that the optical fiber end portion is provided. Has been described, but the present invention is not limited to this configuration.

For example, as shown in FIG.
A notch having a depth approximately equal to or longer than the diameter of the optical fiber is provided only on one side of the optical fiber, the upper lid 11b formed in a plate shape is placed, and the main body 12b and the optical fiber end are placed. And the sealing agent 14 in close contact with each other.
A package a 32b can be used in which the package a 32b is hermetically sealed by bringing the sealing member 14 into close contact with the main body 12b and the region above the end of the optical fiber.

As another configuration, as shown in FIG. 3, an opening slightly larger than the diameter of the optical fiber is provided in advance on the side surface of the main body 12c formed in a box shape, and the end of the optical fiber is connected to the end. After being sealed and fixed with the sealant 14 in a state of being inserted into the opening, the upper lid 11b formed in a plate shape
The package a32c hermetically sealed by bringing the sealing agent 14 into close contact with the opening edge of the main body 12c can be used.

Further, as another configuration, as shown in FIG. 4, a package 32d in which an input optical path and an output optical path are defined by a plurality of columnar members 18 may be used.
Even if the degree of vacuum in the package 32d is increased, the plurality of columnar members 18 support the upper and lower surfaces of the package 32d, so that the package 32d can be prevented from being distorted.

In the matrix optical switch shown in FIGS. 1 to 3, the reflection mechanism 16 is provided above the optical path of the laser beam, but as shown in FIG. A reflection mechanism 16 may be provided at the retracted position so as not to affect the propagation of the laser beam.

In FIG. 4, the rotating shaft 24 is provided upright at a position retracted from the optical paths near the input optical path and the output optical path.
The rotation of the rotation shaft 24 causes the reflection member 2 such as a reflection mirror or the like to rotate.
6 is disposed in the input optical path to reflect the laser beam and guide it to the output optical path, or the reflecting member 26 is disposed at a position retracted from the optical path to pass the laser beam.

In addition, all of the above is at the time of assembling, for example,
It is premised on assembling and sealing in a chamber with a vacuum degree of about 1.0 × 10 ⁻³ Pa or more and about 1.0 Pa or less. For example, a tube whose one end is opened beforehand on either the lid or the main body After all the assembly is completed, the other end of the tube is connected to a vacuum device to evacuate the packages 32a to 32d through the tube, and then the tube is cut to open the tube end. , It is possible to obtain a matrix optical switch in which the inside of the packages 32a to 32d is vacuum.

[0041]

As described above, according to the present invention, it is possible to obtain a matrix optical switch which suppresses various influences of water vapor, dust and dust, has a good response response, is not affected by air resistance, and has a long life. Is effective.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a matrix optical switch according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a matrix optical switch according to another embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a matrix optical switch according to still another embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a matrix optical switch according to still another embodiment of the present invention.

FIG. 5 is a perspective explanatory view schematically showing a conventional matrix optical switch.

FIG. 6 is an explanatory diagram showing another configuration of a conventional reflection device for a matrix optical switch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Matrix optical switch 11a-11c Top lid 12a-12c Main part 14 Sealant 16 Reflection mechanism 18 Columnar member 20a-20d Input side optical fiber 22a-22h Output side optical fiber 24 Rotation axis 26 Reflection member 32a-32d Package

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshihiro Sakamoto 585 Tomicho, Funabashi-shi, Chiba Sumitomo Osaka Cement Co., Ltd. F-term in the New Technology Research Laboratories (Reference) 2H041 AA16 AA18 AB13 AC01 AZ02 AZ06

Claims (1)

[Claims] 1. An at least one input port for guiding a laser beam input from the outside to an input optical path; a selective reflection means for reflecting or passing a laser beam propagating through the input optical path to guide the laser beam to an output optical path; An output port provided at the end of an output light path through which a laser beam reflected or passed by the selective reflection means propagates, at least the input light path, the selective reflection means, and
The matrix optical switch according to claim 1, wherein the output optical path is provided inside the housing with a vacuum inside the housing and inside the housing.