JP2003121764A - Optical switch using rotary wedge prism and optical switch module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a free space type optical switch which is simple and small- sized and an optical switch module. SOLUTION: The optical switch deflects the optical path of signal light. The optical switch and optical switch module have wedge prisms 8a and 8b which are arranged on the optical axis of the signal light 3 of an optical fiber 2 and deflect the optical path, and micromotors 9a and 9b, driving gears 10a and 10b, speed changegears 11a and 11b, and driven gears 13a and 13b as a rotational driving means for rotating the wedge prisms 8a and 8b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical switch and an optical switch module for deflecting an optical path of an optical signal in the communication field. In particular, it relates to a mechanical drive deflection type optical switch and an optical switch module using a free space optical system.

[0002]

2. Description of the Related Art A free-space propagation type optical switch is suitable for a large-scale optical switch having 1000 or more ports because a three-dimensional port arrangement is possible and the number of optical path deflecting devices is twice the number of ports. Are believed to be present.

The structure of the optical switch is composed of an input fiber group, a collimating lens, an optical path deflecting device, a condenser lens and an output fiber group. In the optical path deflecting device, a minute mirror is used and the tilting operation of the mirror is performed. The reflection type in which the optical path of the signal light is deflected by the reflection is mainly used.

The optical path deflecting device comprises an optical micromirror which is an optical component, an electronic circuit of a control system, and a mechanical drive unit for tilting the mirror, which are miniaturized and integrally integrated by a micromachine technique.

Here, the micromachine technology is a three-dimensional microfabrication technology based on the semiconductor fabrication technology, and has attracted attention as a new fabrication technology for realizing miniaturization and high-density integration of mechanical devices.

Even in the integration of optical components, the high precision of component arrangement enables high-precision mounting and multi-channelization. Therefore, the micromachine technology is actively used in the field of optical switches and displays involving optical path deflection. It is applied.

An optical path deflection unit using an optical micromirror is generically called an optical micromirror device, and is roughly classified into an electrostatic drive type and an electromagnetic drive type according to the drive system of the optical micromirror. Both types require a two-dimensional mirror driving operation.

As an example of using an electrostatically driven optical micromirror as an optical switch, an optical switch for a large-scale router by Lucent Co., Ltd. (for example, refer to "Optical Router Promis."
es Faster Net ", IEEE Computer, Jan., pp.26,2000")
In addition, a similar two-dimensional mirror device has been proposed by the University of California (for example, reference document `` L.
Fan and MCWu, "Two-Dimensional Optical Scanner w
ith Large angular Rotation Realized by Self-Assemb
led Micro-Elevator ", Proc. IEEE LEOS Annual Meetin
g on Optical MEMS, Paper WB4, Monterey, Calfornia, Au
gust 20-22, 1998 ”).

FIG. 4 is a diagram showing an electrostatically driven optical switch used in a conventional optical switch for a large-scale router of Lucent. FIG. 4A shows the basic configuration of the electrostatic drive type optical switch, and FIG. 4B shows the outline of the two-dimensional micromirror device.

The electrostatic drive type optical switch 21 includes an input / output integrated optical fiber array 22 and the optical fiber array 2.
2 is a variable mirror array having a microlens array 23 installed in front of the optical axis for collimating and condensing, and a plurality of micromirror devices 24a installed in front of the microlens array 23 for optical path deflection. 24, a macro lens 25 installed in front of the variable mirror array 24 on the optical axis and changing the path of the light beam whose optical path is deflected, and a variable mirror array for changing the path of the light beam by the macro lens 25 again. It is composed of a flat reflecting mirror 26 that reflects in 24 directions.

As shown in FIG. 4A, the optical path of the light beam is switched by the first optical micromirror device 24 located in front of the incident side optical fiber in the optical fiber array 22.
a, the light beam is deflected in the direction of the flat plate reflection mirror 26, and the reflected light is deflected to the emission side optical fiber side by the second optical micromirror device 24a located in front of the emission side optical fiber in the optical fiber array 22. By doing. The above-mentioned first and second optical micromirror devices 24
When a is inclined in the two-dimensional direction, the light beam is deflected, its path is changed, and the output side optical fiber is selected, thereby functioning as an optical switch.

As shown in FIG. 4B, the micromirror device 24a for deflecting the light is deflected in a two-dimensional direction, and the micromirror 27 for deflecting the optical path by reflecting the light beam, and the micromirror 27. In the case of inclining in a two-dimensional direction, the micro mirror 27 inclines in an arbitrary one-dimensional direction, having two pairs of torsion bars 28 and a pair of torsion bars 28 which serve as springs of the inclining operation and play a role of springs. In this case, the outer frame 29b has an inner frame 29a serving as a reference surface and another pair of the torsion bar 28, and serves as a reference surface when the micro mirror 27 and the inner frame 29a are inclined in another one-dimensional direction. And the outer frame 2
It has a support frame 30 that supports 9b.

The micromirror device 24a having electrostatic drive means has a lower surface side of the micromirror 27 and a plurality of electrodes (not shown) for generating static electricity arranged on the substrate immediately below the micromirror 27. The micro mirror 27 and the inner frame 29a are tilted in the respective directions by the electrostatic action of.

Up to now, an optical switch group having a terminal scale of 112 inputs and 112 outputs, in which 256 optical micromirror devices 24a described above are integrated, has been prototyped. Insertion loss is about 8 dB, crosstalk is -50 dB, and switching is performed. It is reported that the time is about 10 msec.

However, the mechanism of the electrostatic drive type optical switch is sensitive to environmental changes such as humidity and the relationship between the drive voltage and the tilt angle is non-linear, so that the optical micromirror is accurately controlled in an analog manner. Is difficult to do. Therefore, a sophisticated feedback mechanism for controlling the mirror angle in real time is required, and there is a problem that the cost of the entire optical switch module increases.

On the other hand, as an example of applying the electromagnetically driven optical micromirror device to a communication optical switch, Astarte
There is an optical cross-connect device from Fiber Networks (hereinafter referred to as Astarte) (for example, reference document "H.Laor," C.
onstruction and performance of a 576x576 single-St
age OXC ", LEOS'99, Vol.2, Paper WK1, pp.481-482,199
9 ”).

FIG. 5 is a diagram showing an electromagnetically driven optical switch used in a conventional optical cross-connect device of Astarte. FIG. 5A shows the basic configuration of the optical cross connect device, and FIG. 5B shows the configuration of the optical path deflector of the optical cross connect device.

As shown in FIG. 5 (a), the electromagnetically driven optical cross-connect device 31 is of a reflection type via a large fixed flat plate mirror 32 as a whole, and is composed of the fixed flat plate mirror 32 and the fixed plate mirror 32. The optical input / output module array has a plurality of optical input / output modules 35a arranged in a two-dimensional array at positions facing the flat mirror 32. Any optical input / output module 35a can be selected by inclining the angle of the optical micromirror 34 in the optical path deflection unit 33 provided in the optical input / output module 35a in a two-dimensional direction by electromagnetic driving. .

As shown in FIG. 5 (b), the optical path deflecting unit 33 of each optical input / output module 35a is arranged in front of and behind the optical fiber 36 for input / output and the optical fiber 36, and collimator and A lens 37 that collects light,
It is composed of a fixed flat plate mirror 38 that reflects a light beam and an optical micromirror 38 that is movable in two dimensions.
A light beam position detector 39 is inserted between the fiber 36 and the lens 37 via a splitter 40, and an LED element 41 is also installed for light beam position monitoring. The signal light emitted from the fiber 36 is collimated by the collimator lens 37.
Is converted into parallel light having a beam diameter of about 3 mm, reflected by the fixed reflection mirror 38, and then applied to the optical micromirror 34.

The electromagnetically driven optical micromirror has high angular resolution and reproducibility, and the optical cross-connect device manufactured by Astarte Co. has a large scale of 576 inputs and 576 outputs. However, the size of the entire device is about 2 m, the amount of hardware in the optical switch configuration is enormous, and there is a problem in downsizing and large-scale integration exceeding the above-mentioned number of inputs and outputs.

[0021]

An optical switch using the above-mentioned optical micromirror and switching the optical path by changing the reflection direction of the signal light by its inclination,
In the electrostatic drive type, there is a problem that the inclination angle is deteriorated mainly due to environmental changes such as humidity, and in the electromagnetic drive type, there is a problem that miniaturization and integration are difficult due to an increase in the amount of hardware.

Further, since both of them use a large fixed mirror, the size of the optical switch main body becomes large and the assembly becomes difficult when integrated with the optical micromirror device array.

Further, in the system in which the optical path is deflected by inclining these optical micromirrors, the terminal interval and the size of the entire module are determined by the mirror inclination angle and its control accuracy. And the maximum tilt angle of the optical micromirror is 1
It is about 0 °, and the input / output terminals are arranged in the range of 20 ° after reflection. Therefore, in order to realize a large number of terminals, a long propagation distance is required, and miniaturization is limited.

Further, in order to realize the miniaturization, it is necessary to make the terminal interval close, which requires a highly accurate mirror tilt mechanism and component placement accuracy.

Therefore, the present invention provides a simple and small free space type optical switch and an optical switch module in order to solve the above problems.

[0026]

An optical switch according to the present invention for solving the above-mentioned problems is an optical switch for deflecting an optical path of a signal light, which is disposed on the optical axis of the signal light of an optical fiber and is capable of deflecting the optical path. It has a wedge prism for performing and a rotation driving means for rotating the wedge prism. In the above invention, the wedge prism is used, and by rotating the wedge prism, the signal light can be refracted in an arbitrary direction to perform optical path deflection.

An optical switch according to the present invention for solving the above-mentioned problems is an optical switch for deflecting an optical path of signal light, which has two wedge prisms, which are arranged in close proximity to each other. It is characterized in that the optical path is deflected by rotating. In the above invention, two wedge prisms are used, they are arranged close to each other, and each is independently rotated, whereby the optical path of the signal light can be deflected at an arbitrary angle in a wide range.

An optical switch according to the present invention for solving the above-mentioned problems is an optical switch for deflecting an optical path of a signal light, wherein the two wedge prisms receive the signal light from the optical fiber or send a signal to the optical fiber. The signal light is emitted to the first wedge prism that emits light and other optical switches,
Alternatively, the second wedge prism receives a signal light from another optical switch, and the deviation angle of the first wedge prism is less than or equal to the deviation angle of the second wedge prism. Is characterized by. In the above invention, 2
Since the wedge prisms each have an appropriate deviation angle and rotate independently of each other, the range of the optical path deflection of the signal light can be effectively used.

An optical switch module according to the present invention for solving the above-mentioned problems is a free space propagation type optical switch module for switching the optical path of an optical signal having the number of input terminals N × the number of output terminals M, which the optical switch module has. An optical switch is arranged on the optical axis of the signal light of the optical fiber,
It is characterized by having a wedge prism for changing the optical path and a rotation driving means for rotating the wedge prism. In the above invention, the wedge prism is used, and by rotating the wedge prism, the optical switch that refracts the signal light in an arbitrary direction to deflect the optical path is used. Optical path switching can be performed.

An optical switch module according to the present invention for solving the above-mentioned problems is a free space propagation type optical switch module for switching the optical path of an optical signal having the number of input terminals N × the number of output terminals M, which the optical switch module has. An optical switch has two wedge prisms, which are arranged close to each other, and are each independently rotated to perform optical path deflection. In the above invention, by using two wedge prisms, arranging them close to each other, and rotating each independently, an optical switch for deflecting the optical path of the signal light at an arbitrary angle and in a wide range is used. , The number of input terminals × the number of output terminals M can be used to switch the optical paths of optical signals.

The optical switch module according to the present invention which solves the above-mentioned problems is a free space propagation type optical switch module for switching the optical path of an optical signal having the number of input terminals N × the number of output terminals M, wherein the two wedge prisms are used. Is a first wedge prism that receives the signal light from the optical fiber or emits the signal light to the optical fiber, and emits the signal light to another optical switch, or outputs the signal light from another optical switch. The second wedge prism receives the second wedge prism, and the deviation angle of the first wedge prism is less than the deviation angle of the second wedge prism. In the above invention, the two wedge prisms have an appropriate deviation angle and rotate independently of each other, thereby using the optical switch that effectively uses the range of the optical path deflection of the signal light,
It is possible to switch the optical paths of the optical signals of N input terminals × M output terminals.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION (Example 1) FIG. 1 is a structural example of a space propagation type optical switch module according to a first embodiment of the present invention.

As shown in FIG. 1, the spatial propagation type optical switch module 1 is connected to a plurality of optical fibers 2 and has an incident side optical fiber array having N terminals (N terminals) arranged on the input side of the signal light 3. 4a and the incident side optical fiber array 4
It is arranged on the front surface of a and corresponds to each optical fiber 2,
An incident side microlens array 5a for collimating to make parallel light of the signal light 3 and an incident side optical path deflector arranged on the front surface of the incident side microlens array 5a for deflecting the optical path of the signal light 3 of each optical fiber 2. Device array 6a
And a plurality of optical fibers 2 are connected to each other, the output side optical fiber array 4b having the number M of terminals (M terminals) arranged on the output side of the signal light 3, and the front side of the output side optical fiber array 4b, The microlens array 5b on the output side that collects the signal light 3 from the side and the optical path deflecting device array 6a on the input side are arranged in parallel with each other across a space of an arbitrary distance, and are arranged parallel to each other. The output side optical path deflecting device array 6b for deflecting the optical path of the signal light 3 of FIG. Optical fiber arrays 4a and 4b, microlens arrays 5a and 5b, and optical path deflection device arrays 6a and 6b
Are installed at positions that face each other on the incident side and the emitting side.

N and M optical fibers 2 are connected to the incident-side fiber array 4a and the outgoing-side optical fiber array 4b, respectively. It is manufactured by passing the optical fiber 2. The number N of optical fibers 2 connected to the entrance side fiber array 4a and the number M of optical fibers 2 connected to the exit side optical fiber array 4b do not necessarily have to be equal, and may be any number depending on the situation. You can choose.

The microlenses include a light-collecting lens having a difference in refractive index distribution and an end-face refracting lens having a curvature end face. The microlens arrays 5a and 5b are produced by a general ion-exchange method. End face refraction lens by a directivity method using a transparent lens, a laser beam, and a polymer casting method using a mold has been put to practical use, and a microlens array 5 having high uniformity in lens performance.
It is possible to inexpensively integrate a and 5b on the same substrate with high density. The incident surfaces of the microlens arrays 5a and 5b are provided with antireflection coating for the wavelength range of the signal light. In addition, without using the microlens arrays 5a and 5b,
There is also a case where the end surface of the optical fiber 2 is processed into a lens shape to form an array.

In the incident side optical path deflecting device array 6a,
A cylindrical wedge prism having an inclination in the optical axis direction is used, and the deflection angle of the signal light 3 can be freely set by adjusting the inclination angle. By arranging the prism also on the exit side optical path deflecting device array 6b,
In principle, the deflection angle can correspond to 0 to less than 90 °, and the maximum deflection angle of 20 ° of the electrostatically driven micromirror device can greatly exceed 45 ° and 60 °.

As means for freely setting the deflection angle of the wedge prism, for example, one or a plurality of wedge prisms are arranged on the optical axis of the signal light 3 of the optical fiber 2, and each wedge prism is This can be realized by providing a rotation drive means capable of rotating along the side surface direction.
By using the above means, the signal light 3 can be deflected in an arbitrary direction by controlling the rotational position of the wedge prism.

Optical path deflecting device arrays 6a and 6b
Is an optical path deflecting mechanism having a deflecting mechanism different from that of a reflection type in which a conventional optical micromirror is tilted, and the optical path is deflected by deflecting the transmitted light of the signal light 3 with a wedge prism. Therefore, by directly deflecting the signal light and propagating it in free space, the fixed mirror can be eliminated, and a small optical switch module with low loss can be realized.

The size of the depth and height of the optical switch module is determined by the number of terminals and the array spacing of the optical fiber array and the microlens array, and the array spacing depends on the size of the optical path deflecting device. The size of the optical switch module in the longitudinal direction including the free space is designed by the polarization angle of the optical path deflecting device and the array interval. The polarization angle depends on the refractive index and elevation angle of the prism used and the numerical aperture of the microlens. It can be set flexibly by adjusting. Therefore, it is possible to flexibly deal with the input / output terminal spacing and the terminal array spacing, and further contribute to the miniaturization of the large-scale optical switch module.

(Embodiment 2) FIG. 2 is a perspective view of a configuration example of an optical path deflecting mechanism of a space propagation type optical switch module according to a second embodiment of the present invention. In FIG. 2, the optical fiber 2 in the incident side optical fiber array 4a (see FIG. 1) and the micro fiber in the incident side microlens array 5a (see FIG. 1) are shown in order to clearly show the optical path deflection of any one system. The lens 5 is also shown.

As shown in FIG. 2, the optical path deflecting device 7
Are two cylindrical wedge prisms 8a and 8b, micromotors 9a and 9b for rotating the wedge prisms 8a and 8b, and drive gears 10a and 10b.
And the transmission gears 11a, 11b and the like, and the wedge prisms 8a, 8b and the micromotors 9a, 9b are connected with high precision via the drive gears 10a, 10b and the transmission gears 11a, 11b. The above components are the substrate 12
It is properly placed on top.

The light beam from the optical fiber 2 is converted into parallel light by the microlens 5 for collimation. The light beam converted into parallel light is deflected in an arbitrary direction by the first wedge prism 8a and the second wedge prism 8b which are arranged close to each other on the same optical axis as the light beam.

Each of the wedge prisms 8a and 8b has a shape in which one end face of a cylinder is obliquely cut and has an outer circumference suitable for rotation. The first wedge prism 8a is arranged such that the inclined end surface faces the optical fiber 2 side and the other vertical end surface faces the second wedge prism 8b side. A driven gear 13a is provided on the outer peripheral surface of the first wedge prism 8a. On the other hand, a micromotor 9a is installed on the substrate 12, a drive gear 10a is provided on its rotation shaft, and this drive gear 10a is meshed with a transmission gear 11a. This transmission gear 11a is meshed with a driven gear 13a. There is. Therefore, by driving the micromotor 9a, the first wedge prism 8a rotates along the outer peripheral surface direction via the drive gear 10a, the transmission gear 11a, and the driven gear 13a.

The second wedge prism 8b is arranged such that its vertical end face is on the first wedge prism 8a side and the other end face with inclination is on the free space side. Similarly to the first wedge prism 8a, the second wedge prism 8b also has the driven gear 1 on the outer peripheral surface of the second wedge prism 8b.
3b is provided. On the other hand, a micromotor 9b is installed on the substrate 12, a drive gear 10b is provided on its rotating shaft, and this drive gear 10b is meshed with a transmission gear 11b. This transmission gear 11b is meshed with a driven gear 13b. There is. Therefore, the micromotor 9b
The second wedge prism 8b is driven by the drive gear 10b, the transmission gear 11b, and the driven gear 13b.
Rotate along the outer peripheral surface direction.

By rotating the wedge prisms 8a and 8b independently of each other, the respective deviation angles with respect to the incident signal light 3 and the outgoing signal light 3 are changed. Control the angle of.

With the above structure, it is possible to deflect the signal light in a plane direction perpendicular to the optical axis direction of the signal light of the input side optical fiber 2 in one optical path deflecting mechanism, and the optical path deflecting device 7 is provided. It is possible to increase the density.

In the above optical path deflecting device 7, individual microstepping motors and micro ultrasonic motors are adopted as motors for rotating the wedge prisms 8a and 8b, and two motors are provided for each optical path deflecting device. Are accumulated. Since these motors have a high angular resolution of 0.1 ° or less, it is possible to control the optical path deflection with high accuracy. In the future, further miniaturization and high-density integration will be possible by adopting a wobble motor, a micro gear, or the like manufactured by using the micromachine technology.

The optical path deflecting device 7 of the same type is also installed on the exit side, and the signal light deflected at an arbitrary angle with respect to the optical axis of the incident side optical fiber array 4a is deflected on the exit side. It is re-deflected by the device 7 in parallel so as to be aligned with the optical axis of the output side optical fiber 4b.

FIG. 3 shows two wedge prisms 8a and 8a.
It is a figure which shows the principle of optical path deflection by b. The signal light is deflected by rotating the two wedge prisms 8a and 8b with respect to each other. The trajectory of the deflection of the signal light is described in the reference document (GC Boisser, B. Rdbertson, HSHinton, "Design and
Construction of an Active Alignment Demonstrator f
or a Free-Space Optical Interconnection ", IEEE Photo
n. Technol. Lett., vol.7, no.6, pp.676-678, June, 199
As shown in 5), a locus is drawn such that the center of the second circle generated by the rotation of the second prism passes on the first circle generated when the first prism is rotated. The radii of the first and second locus circles are determined by the width L of the free space between the incident side optical path deflecting device and the emitting side optical path deflecting device, and the deflection angle θd of the prism, and θd is the refractive index of the prism material and the light. It is determined by the angle of inclination of the prism end face with respect to the axis.

As shown in FIG. 3, the wedge prism 8
When the deflection angles of a and 8b are both θd, and the optical axis of the light beam and the rotation center of the wedge prisms 8a and 8b coincide with each other, the deflectable range of the signal light is the radius (L × tan2θd).
It is inside the circle represented by. Therefore, it is necessary to arrange all the terminals on the output side inside this circle, and it is possible to flexibly deal with it by optimally designing L and θd.

In the optical path deflecting device 7 described above, the wedge prisms 8a and 8b both have a deviation angle of θd, but the wedge prisms 8a and 8b do not necessarily have to have the same deviation angle. For example, the deflection angle of the first wedge prism 8a is θd1, and the deflection angle of the second wedge prism 8b is θd2.
The above optical path deflection is possible even when the deflection angle is different from. However, when the deviation angles θd1 and θd2 are different from each other, the deviation angle θd1 of the first wedge prism 8a must be equal to or less than the deviation angle θd2 of the second wedge prism 8b. This is because the deviation angle θd1 of the first wedge prism 8a is
When larger than the deflection angle θd2 of the wedge prism 8b, the radius of the first circle of the optical path deflection of the first wedge prism 8a having the deflection angle θd1 is the trajectory of the optical path deflection of the second wedge prism 8b having the deflection angle θd2. This is because the radius is larger than the radius of the second circle and the optical path cannot be deflected in the central portion of the first circle. Therefore, in order to avoid this, when the deviation angles of the wedge prisms 8a and 8b are different, the condition that the deviation angle θd1 of the first wedge prism 8a is equal to or less than the deviation angle θd2 of the second wedge prism 8b is necessary.

In the above description, the case where the light deflecting device 7 is used on the incident side is described. However, when the light deflecting device 7 is used on the emitting side, the deflection angle θd1 of the first wedge prism 8a.
However, when the condition of being less than the deviation angle θd2 of the second wedge prism 8b is not satisfied, when the signal light 3 from the incident side is incident on the light deflection device 7 on the emission side, it is parallel to the optical fiber 2 on the emission side. There are some conditions that cannot be deflected in the direction. Therefore, also in the light deflecting device 7 on the emission side, when the deviation angles of the wedge prisms 8a and 8b are different, the condition that the deviation angle θd1 of the first wedge prism 8a is equal to or less than the deviation angle θd2 of the second wedge prism 8b is necessary. Becomes

Although the optical path deflecting mechanism according to the present invention has been described in the first and second embodiments with reference to FIGS. 1 and 2, the present invention is not limited to the embodiments of these drawings.

[0054]

According to the first aspect of the present invention, a structure is provided which has a wedge prism arranged on the optical axis of the signal light of the optical fiber and which changes the optical path, and a rotation drive means for rotating the wedge prism. Since the wedge prism is used for the optical path deflecting unit to rotate and drive them, the signal light can be deflected, so that a low-loss, simple and small-sized optical switch can be realized.

According to the second aspect of the present invention, two wedge prisms are provided, and the wedge prisms are arranged close to each other, and the optical path is deflected by rotating each independently, and the optical path deflector is provided. Since two wedge prisms are used for the two, they are arranged close to each other, and they are independently driven to rotate, so that it is possible to deflect the signal light in a wide range in a plane direction perpendicular to the optical axis direction. A low-loss, simple and compact optical switch can be realized.

According to the third aspect of the invention, the two wedge prisms receive the signal light from the optical fiber or emit the signal light to the optical fiber, and the other wedge prism and other light. The second wedge prism emits signal light to the switch or receives signal light from another optical switch. The deviation angle of the first wedge prism is determined by the deviation angle of the second wedge prism. The angle is less than or equal to the angle, and the two wedge prisms used for the optical path deflector have proper declination angles, and each is independently driven to rotate, and a wide range is achieved in the plane direction perpendicular to the optical axis direction. Since it is possible to have a lean signal light deflection range, it is possible to realize an optical switch that is low in loss, simple, and small.

According to the invention of claim 4, the optical switch of the optical switch module is arranged on the optical axis of the signal light of the optical fiber, and the wedge prism for changing the optical path and the wedge prism are rotated. Since it is possible to deflect the signal light by rotating and driving the wedge prism in the optical path deflecting unit, it is possible to deflect the signal light. This can contribute to higher density and smaller size of large-scale optical switch modules.

According to the fifth aspect of the present invention, the optical switch included in the optical switch module has two wedge prisms, which are arranged close to each other, and are rotated independently of each other. The optical path is deflected,
Two wedge prisms are used for the optical path deflector, they are placed close to each other, and each can be independently driven to rotate, so that the signal light can be deflected over a wide range in the plane direction perpendicular to the optical axis direction. Therefore, a low-loss, simple, and small-sized optical switch module can be realized, which can contribute to high-density and small-sized large-scale optical switch module.

According to the sixth aspect of the present invention, the two wedge prisms receive the signal light from the optical fiber or emit the signal light to the optical fiber, and the other wedge prism and other light. The second wedge prism emits signal light to the switch or receives signal light from another optical switch. The deviation angle of the first wedge prism is determined by the deviation angle of the second wedge prism. The angle is less than or equal to the angle, and the two wedge prisms used for the optical path deflector have proper declination angles, and each is independently driven to rotate, and a wide range is achieved in the plane direction perpendicular to the optical axis direction. Since it is possible to have a lean signal light deflection range, it is possible to realize an optical switch module that is low in loss, simple, and small, and contributes to high density and miniaturization of a large-scale optical switch module.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of an optical switch module showing a first example of an exemplary embodiment according to the present invention.

FIG. 2 is a perspective view showing an optical path deflecting device using a wedge prism of an optical switch module showing a second example of the embodiment according to the present invention.

FIG. 3 is a diagram showing the principle of optical path deflection of an optical path deflecting device using a wedge prism of an optical switch module showing a second example of the embodiment according to the present invention.

FIG. 4 is a diagram showing a conventional electrostatic drive type optical switch for a large-scale router. (A) is a figure which shows the basic composition of an optical switch, (b) is a figure which shows the outline of a two-dimensional electrostatic drive type optical micromirror device.

FIG. 5 is a diagram showing an electromagnetically driven optical cross-connect device as a conventional technique. (A) is a figure which shows the basic composition of an optical cross-connect apparatus, (b) is a figure which shows the basic composition of the optical path deflection unit which used the optical micromirror.

[Explanation of symbols]

1 Space propagation type optical switch module 2 optical fiber 3 signal light 4a Incident side optical fiber array 4b Output side optical fiber array 5a Incident side microlens array 5b Emitting side microlens array 6a Incident side optical path deflection device array 6b Emission side optical path deflection device array 7 Optical path deflection device 8a First wedge prism 8b Second wedge prism 9a Micromotor 9b micro motor 10a drive gear 10b drive gear 11a speed change gear 11b speed change gear 12 substrates 13a Driven gear 13b Driven gear 21 Electrostatic drive type optical switch 22 Optical fiber array 23 Micro lens array 24 Variable mirror array 24a micro mirror device 25 macro lens 26 Flat reflective mirror 27 micro mirrors 28 torsion bar 29a inner frame 29b outer frame 30 support frame 31 Electromagnetic drive type optical cross connect device 32 flat mirror 33 Optical path deflection unit 34 Optical micro mirror 35 Optical Input / Output Module Array 35a optical input / output module 36 optical fiber 37 lens 38 Fixed flat mirror 39 Light beam position detector 40 beam splitter 41 LED

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuyuki Inoue             2-3-1, Otemachi, Chiyoda-ku, Tokyo             Inside Telegraph and Telephone Corporation (72) Inventor Takeshi Kitagawa             2-3-1, Otemachi, Chiyoda-ku, Tokyo             Inside Telegraph and Telephone Corporation F-term (reference) 2H041 AA14 AA16 AA17 AB26 AC01                       AZ02 AZ05

Claims (6)

[Claims] 1. An optical switch for deflecting the optical path of signal light, comprising: a wedge prism disposed on the optical axis of the signal light of an optical fiber for deflecting the optical path; and a rotation driving means for rotating the wedge prism. An optical switch characterized by that. 2. The optical switch according to claim 1, wherein the two wedge prisms are provided, the wedge prisms are arranged close to each other, and the optical paths are deflected by rotating each independently. Optical switch. 3. The optical switch according to claim 2, wherein the two wedge prisms receive a signal light from an optical fiber or emit a signal light to the optical fiber. The second wedge prism emits a signal light to the optical switch or receives a signal light from another optical switch. The magnitude of the deviation angle of the first wedge prism is equal to that of the second wedge prism. An optical switch having a declination of not more than a magnitude. 4. A free space propagation type optical switch module for switching an optical path of an optical signal having the number of input terminals N × the number of output terminals M, wherein the optical switch included in the optical switch module has an optical axis of signal light of an optical fiber. An optical switch module comprising: a wedge prism disposed on the top of the wedge prism for deflecting an optical path; and a rotation driving unit for rotating the wedge prism. 5. The optical switch module according to claim 4, wherein the optical switch included in the optical switch module has two wedge prisms, which are arranged in close proximity to each other and rotate independently of each other. An optical switch module characterized by performing optical path deflection by doing so. 6. The optical switch module according to claim 5, wherein the two wedge prisms receive a signal light from an optical fiber or emit a signal light to the optical fiber, and Of the second wedge prism that emits the signal light to the optical switch or receives the signal light from another optical switch. The magnitude of the deflection angle of the first wedge prism is the second wedge prism. An optical switch module having a deviation angle of less than or equal to.