JPH0246431A - Two-dimensional optical switch - Google Patents

Abstract

PURPOSE:To operate two-dimensional optical switches at a high speed and to prevent an increase in size without having a need for adding a registering device even if matrices are increased by providing mirrors to both ends of optical switch waveguides which are disposed in plurality and reflecting incident and exit light nearly perpendicularly. CONSTITUTION:The light rays condensed by respective lenses L-11-19 of lens arrays 10-1 are reflected in nearly the perpendicular direction by a 1st mirror M1 disposed at one end of the optical waveguide OG of the respective switches 22-1-9 of an optical switch switch part 20 and are made incident thereto. The light rays which are subjected to switching and shutting off of the optical paths by the optical switches and are emitted from the other end are reflected in nearly the perpendicular direction by the 2nd mirror M2, are transmitted through respective lenses L-21-29 of a lens array 10-2 and are emitted from the respective two-dimensional optical switches. All of the lens arrays, the optical switches and the mirrors are formable to accurate sizes by fine processing techniques and, therefore, the registration over the entire part is executed if the registration of the two optical switches at both ends is executed.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a two-dimensional optical switch that can simultaneously switch or block the optical paths of light propagating through a plurality of optical waveguides or a plurality of spatial beams. It is something.

(Prior Art) Optical switches of various structures have been proposed and put into practical use for switching or blocking the optical path of propagating light. These optical switches mainly have a structure that switches or blocks the optical path of light propagating through one or multiple optical waveguides arranged in a straight line, or the optical path of one or multiple spatial beams arranged in a straight line. It is something. The structure of these optical switches is interference type (phase control type).
Various types are known, such as directional coupling type, refractive index distribution type, etc.

Figure 2 is a structural diagram of an interference type (Matsuhatsu Enda type) optical switch, which is a typical optical switch. In the figure, 1 is an optical waveguide, 2-1, 2-2 is an electrode, and 3 is a substrate made of LiNbO2. be. This optical switch switches the optical path using the electro-optic effect. For example, by applying a voltage to the electrode 2-], the phase of the light propagating through the optical waveguide]a is changed, and the two optical waveguides 1a and lb The emitted light is turned on and off by interfering with the light propagating through it.

In this figure 2, one optical switch is arranged on one board, and whether it is possible to turn on and off in response to one incident light, we can see if multiple optical switches are arranged on the same board at the same time. Various proposals have also been made regarding so-called two-dimensional optical switches that can switch or block optical paths of a plurality of lights in parallel.

Figures 3 to 6 show the conventional two-dimensional optical switches 1 to 6.
This shows a fourth structural example, which will be explained in order below.

FIG. 3 is a perspective view showing the first structural example, and in the figure, 4-1
．． 4-2 is a lens array formed by arranging a plurality of lenses L, for example, 9 lenses in a 3x3 matrix, 5-1.5-
2.5-3 is an optical switch section in which a plurality of optical switches (for example, three optical switches ○SW) are arranged in parallel on the same substrate, and between the lens arrays 4-1 and 42, the input end of each optical switch O8W and the lens array are arranged. The optical switch parts 5-1, 52, and 5-3 are arranged so that the output end of each lens array 4-1 faces each lens (not shown in FIG. 3) of the lens array 4-2. The structure is such that each optical switch O8W (nine pieces) is turned on and off individually for light propagating in a seven-trix pattern.

Further, FIG. 4 is a perspective view showing an example of the second +b structure;
The difference from the example is that between lens array 4-]- and 42,
One optical switch section 5-4 is provided with a plurality of, for example, nine optical switches O8W arranged in parallel, and the light propagated in a seven-trix shape and transmitted through the lens array 4-1 is transmitted to the mirrors 6-1 to 6.
-4 to each optical switch O8W of the optical switch section 5-4.
The structure is such that the output light from each optical switch O8W is guided to each lens L of the lens array 4-2 using a mirror in the same way.

Furthermore, FIG. 5 is a perspective view showing a third structural example, and FIG.
The difference from the above example is that instead of using a mirror, the light transmitted through each lens L of the lens array 4-1 is transferred to an optical fiber FB.
The light emitted from these optical switches SW is guided to each lens L of the lens array 4-2 using an optical fiber FB.
It is made of 114 buildings.

FIG. 6(a) is a perspective view showing the fourth structural example, FIG.
b) is an explanatory diagram of its operating principle, and unlike the first to third examples above, this two-dimensional optical switch utilizes the magneto-optical effect (Faraday effect) (William E.
Ross, Two-dimensiona1mag
netO-OpttC5pattal light m
odulator forsignal proses
sjng, 0PTICAL ENGINEERIN
GVOL, No, 4. p485-490.1983).

In FIG. 6, 6-1 and 6-2 are plural, for example, 1
A lens array formed by arranging two lenses L in a 3x4 matrix, 7 a polarizing plate that transmits only light having a predetermined polarization plane among the light transmitted through each lens L of the lens array 6-1, 8 ] Two optical switch elements 8-1~
8-12 or 7 An optical switch section arranged in a trix shape and rotates the polarization plane of light transmitted through a polarizing plate 7 by a predetermined angle based on the principle described below; 9 denotes each optical switch element 8-1 of the optical switch section 8; This is an analyzer plate that transmits only light whose polarization plane has been rotated in a predetermined direction as described later among the light that has passed through the lenses 8-12 to 8-12, and outputs it to the lens array 6-2.

The operating principle of this two-dimensional optical switch is as shown in FIG. When the light enters the optical switch elements 8-1 and 8-2, the optical switch element 8-1 is in the on state, whereas the optical switch element 8-2 is in the off state and the magnetization direction is reversed. As a result, the rotation direction of the plane of polarization of the light passing through each optical switch element 8-1, 8-2 is reversed as shown in FIG. 3(b). When these lights enter the analyzer plate 9, only the light in the on state enters the analyzer plate 9.
is transmitted, and light in the off state is blocked. In this manner, the two-dimensional optical switch according to the fourth example turns the light on and off by changing the magnetization direction of each of the optical switch elements 8-1 to 8-12 of the optical switch section 8. ing. In this optical switch section 8, a magnetic film is grown on a non-magnetic substrate, and the optical switch elements 8-1 to 812 are arranged in a matrix by etching. Furthermore, the magnetization direction is controlled by individually passing current through each of the electrodes arranged in a matrix. Also,
The switching speed of this optical switch is 1 μs.

In addition, there are two-dimensional optical switches with structures that utilize various principles (Recent Trends in Spatial Light Modulators, Optronics, No.

4.1985), the optical path switching speed is several μ
s to several weights s is common.

(Problem to be Solved by the Invention) However, according to the first example, each optical switch section 5-1.5-2.5-3 is aligned with the lens array 4-1, and each Since it is necessary to input light into the optical switch O8W, it takes a considerable amount of time to align it, and a large number of devices are required for alignment, which leads to an increase in size and cost. there were.

In addition, according to the second example, a large number of mirrors are required, and a large number of devices are required to improve the alignment accuracy of the mirrors, which, like the first example, has the problem of increasing the size. .

Furthermore, according to the third example, in order to achieve miniaturization, it is necessary to shorten the length of the optical fiber FB, but this reduces the radius of curvature and increases loss in that part, making it difficult to miniaturize. be. Furthermore, a positioning device is also required to align the optical fiber FB and each lens L. There was still the problem of increasing the size.

Furthermore, in the first to third examples above, if the number of signal lights to be processed increases, the number of matrices will inevitably increase, which will require a positioning device, which will lead to further increase in size. .

Furthermore, according to the fourth example, since there is no need for a positioning device, there is little risk of increasing the size, but the switching speed is about 1 μs and the electro-optic effect is used.
There is a problem in that the light intensity is slower than that of a device that can switch the optical path at about Ins or less.

In view of the above-mentioned problems, an object of the present invention is to eliminate the need for a device for positioning each lens of the lens array and each optical switch of the optical switch section, eliminate the risk of increasing the size, and provide a fast and accurate An object of the present invention is to provide an excellent two-dimensional optical switch capable of switching and blocking optical paths.

(Means for Solving the Problem) In order to achieve the above object, in claim (1), a lens array and a plurality of optical waveguide type optical switches that switch or block the optical path of light transmitted through the lens array are arranged. In the two-dimensional optical switch, the optical waveguides of each optical switch are arranged so that the waveguide axes thereof are substantially perpendicular to the light transmission direction of the lens array, and A first mirror is disposed on one end side to reflect the transmitted light of the lens array and make it enter the optical waveguide, and on the other end side, the first mirror is arranged to reflect the light emitted from the optical waveguide in a direction substantially perpendicular to the output direction. A second mirror was placed.

Further, in claim (2), a lens array and a polarizing plate;
There is an optical switch section consisting of a plurality of optical waveguide type optical switches that rotate the polarization plane of the light transmitted through these lens arrays and polarizing plates by a predetermined angle, and only the light whose polarization plane has been rotated by each switch in the optical switch section. In the two-dimensional optical switch, the optical waveguides of each optical switch are arranged so that the waveguide axes thereof are substantially perpendicular to the light transmission direction of the lens array and the polarizing plate, and A first mirror is disposed on one end side of the waveguide to reflect the transmitted light of the lens array and the polarizing plate and make it enter the optical waveguide,
Further, a second mirror was disposed on the other end side to reflect the light emitted from the optical waveguide and make it enter the analyzer plate.

(Function) According to claim (1), the light that has been focused and transmitted by each lens of the lens array is collected by the first mirror disposed at one end side of the optical waveguide of each optical switch in the optical switch section. The light is reflected in a direction substantially perpendicular to the transmission direction and enters the optical waveguide from one end thereof. The optical path of the light incident on the optical waveguide is switched or blocked by each optical switch. In this way, the light switched by the optical switch further propagates through the optical waveguide and exits from the other end. The light emitted from this optical waveguide is reflected by the second mirror in a direction substantially perpendicular to the emitting direction, and is emitted from the two-dimensional optical switch.

According to claim (2), the light is focused and transmitted by each lens of the lens array, and is further transmitted through a polarizing plate so that the plane of polarization is aligned, or is transmitted through a polarizing plate so that the plane of polarization is aligned, and then further transmitted through the lens. The light that has been focused and transmitted by each lens in the array is reflected by the first mirror placed at one end of the optical waveguide of each optical switch in the optical switch unit in a direction approximately perpendicular to the transmission direction, and is reflected into the optical waveguide. The light enters from one end. The plane of polarization of the light incident on the optical waveguide is rotated by a predetermined angle by each optical switch. The light whose plane of polarization has been rotated further propagates through the optical waveguide and exits from the other end. The light emitted from this optical waveguide is reflected by the second mirror in a direction almost perpendicular to the direction of light emitted, and then enters the analyzer plate.The light whose polarization plane has been rotated passes through the analyzer plate, and The light is emitted from the optical switch.

(Example)] 2 Fig. 1 shows a first embodiment of a two-dimensional optical switch according to the present invention, Fig. 1(a) is a perspective view thereof, and Fig. 1(a) is a perspective view thereof.
b) is an enlarged sectional view taken along line A-A in FIG. 1(a). In the figure, 10-110-2 is a plurality of lenses, for example, nine lenses L-11 to L-19 and L21 to L2.
9 is a lens array arranged in a 3x3 matrix; 20 is an optical switch section disposed between the lens array 10-1 and the lens array 102; Lens L-11~
Nine optical waveguide type optical switches 22-1 to 22- that switch or block the optical path of light transmitted through L-19.
9 are arranged in a 3x3 matrix.

Each of the optical switches 22-1 to 22-9 is of a phase control type, a directional coupling type, a refractive index distribution type, etc., and each optical waveguide OG, which is a main component thereof, is connected to its waveguide axis, that is, in the light propagation direction. is arranged so as to be substantially perpendicular to the light transmission direction of lens array 10-1.

Furthermore, a lens array 10 is provided at one end of each optical waveguide OG.
A first mirror M1 is arranged to reflect the transmitted light of each lens L ], ] to L1-9 and make it enter the optical waveguide OG, and the other end side reflects the light emitted from the optical waveguide OG. Each lens L-21 to L-29 of the lens array 102 is reflected in a direction substantially perpendicular to the emission direction (downward in the drawing).
A second mirror M2 is arranged to make the light incident on the light beam. Also,
EL is an electrode loaded on the optical waveguide OG.

In addition, as shown in FIG. 1(b), the first and second mirrors M
Grooves for arranging 1 and M2 can be made by etching, and aluminum is placed in these grooves.

The first and second mirrors M] and M2 can be manufactured by depositing gold, silver, or the like.

Next, the operation of the above configuration will be explained. Lens array 1
The light that has been collected and transmitted by each lens L-11 to L-19 of 0-1 is transmitted to each optical switch 22-1 of the optical switch section 2o.
~22-9, reaches the first mirror M placed at one end of the optical waveguide OG], is reflected by this first mirror M1 in a direction substantially perpendicular to the transmission direction, and enters the optical waveguide OG from the one end. incident. The optical path of the light incident on the optical waveguide OG is switched or blocked by changing the phase or the like, for example, by applying a voltage to each electrode EL in each of the optical switches 22-1 to 22-9. In this way, the light switched by each of the optical switches 22-1 to 22-9 further propagates through the optical waveguide OG and exits from the other end. The light emitted from this optical waveguide OG is reflected by the second mirror M2 in a direction substantially perpendicular to the emitting direction, that is, emitted to the lower surface side of the substrate 21, and is emitted to each lens L of the lens array 10-2.
-21 to L-29, passes through them, and is emitted from the two-dimensional optical switch.

As described above, according to the embodiment of Section 1, the lens array 10-1, 10-2, each optical switch 22-1 to 22-9 of the optical switch section 20, and each optical switch 22-1 to 22
Since the first and second mirrors arranged at both ends of the optical waveguide OG of -9 can be manufactured using microfabrication technology, the dimensions of each part and the interval between each part can be manufactured with high precision. Therefore, when the two optical switches at both ends of the substrate 21 are aligned, the alignment of the optical switches 22-1 to 22-9 of the entire optical switch section 20 is completed. For this reason, lens array 10-1. The unit 0-2 and the optical switch section 20 can be aligned relatively easily, and there is no need to provide a device for alignment, and no increase in size occurs. Furthermore, even if the number of matrices increases, two lens arrays 10-1.
It is only necessary to align the optical switch section 20 consisting of the optical switch section 10-2 and one substrate 21, and thereby the number of devices for alignment does not increase and the size does not increase.

Furthermore, first and second mirrors Ml are installed at both ends of the optical waveguide OG of a waveguide type optical switch such as a phase control type or a directional coupling type.
, M2 are only provided, there is no effect on the optical path switching speed, and therefore, optical path switching can be performed at a high speed of about Ins or less.

FIG. 7 shows a second embodiment of the two-dimensional optical switch according to the present invention, FIG. 7(a) is a perspective view thereof, and FIG.
b) is an enlarged sectional view taken along line B-B in the arrow direction of FIG. 7(a). The difference between the embodiment of this section 2 and the first embodiment is that each optical switch 22-1 to 22-9 of the optical switch unit 20
This is because the second mirror M2 disposed on the other end side of the optical waveguide OG is arranged so that the reflection direction is not toward the lower surface of the substrate 21 but toward the upper surface thereof. As a result, the lens L-11 condenses the incident light onto the lens array 10-1 and transmits the light.
Lenses L-11- to L-19' can be arranged in parallel to L-19 to condense and transmit the light that has passed through the optical switch section 20 and been reflected by the second mirror M2. The lens array 10-2 in the embodiment becomes unnecessary.

Therefore, according to the second embodiment, in addition to the effects of the first embodiment, the two-dimensional optical switch can be made smaller.

FIG. 8 is a perspective view showing a third embodiment of the two-dimensional optical switch according to the present invention. The difference between the embodiment of this section 3 and the first embodiment is that each lens L-
In addition to disposing a polarizing plate 30 for aligning the plane of polarization of the light transmitted through L-11 to L-19, the plane of polarization of each optical switch 22-1 to 22-9 of the optical switch section 20 can be rotated. Optical waveguide type optical switch (substrate 21 is LiNb
O3 substrate), for example, a phase modulator, and further, between the optical switch section 20 and the lens array 10-2, the plane of polarization is rotated by each of the optical switches 22-1 to 22-9 of the optical switch section 20. This is because an analyzer plate 40 is provided that transmits only the reflected light.

Here, the operation according to the embodiment of Section 3 will be explained.

The light that has been collected and transmitted by each of the lenses L-11 to L-19 of the lens array 10-1 is then transmitted through the polarizing plate 30 so that the plane of polarization is aligned, and the light is transmitted through each optical switch 22-1 of the optical switch section 20.
The light is reflected by the first mirror M1 disposed at one end of the optical waveguide OG of ~22-9 in a direction substantially perpendicular to the transmission direction thereof, and enters the optical waveguide OG from one end. The light incident on the optical waveguide OG passes through each optical switch 22-1 to 22-9.
, the plane of polarization is rotated by a predetermined angle by the voltage applied to the electrode EL. The light whose polarization plane has been rotated further propagates through the optical waveguide OG and exits from the other end. The light emitted from this optical waveguide is reflected by the second mirror M2 in a direction substantially perpendicular to the emitted direction, and enters the analyzer plate 40,
The light whose polarization plane has been rotated by each optical switch in the on state is transmitted through the analyzer plate 4o, and then passes through each lens L of the lens array 1o-2.
-2] enters L-29, passes through them, and is emitted from the two-dimensional optical switch.

Similarly to the first embodiment, the embodiment of this section 3 does not cause the risk of increasing the size of the two-dimensional optical switch, and moreover, the L iN
b In the case of an optical switch fabricated on a substrate 21 such as Oa, it is possible to switch the optical path in about ]ns or less, and the first and second mirrors MI M2 are arranged at both ends of the optical waveguide OG of this optical switch, respectively. This does not affect the optical path switching speed, and therefore high-speed switching of less than about Ins is possible.

(Effect of the invention) As explained above, claim (1) or claim (2)
According to , in order to switch or block the optical path of light that propagates in a 7-trix pattern, the optical path can be switched or blocked to the corresponding position, or the plane of polarization can be rotated. The optical switch section includes a plurality of optical waveguide-type optical switches that can perform 1
mirror and a second mirror that reflects the light emitted from the optical waveguide in a direction almost perpendicular to the direction of light emitted from it, which has the advantage of realizing a two-dimensional optical switch that can perform high-speed switching operations. . Further, even if the number of matrices increases, there is no need to add a device for alignment, which has the advantage of preventing the two-dimensional optical switch from increasing in size.

[Brief explanation of the drawing]

Fig. 1 shows a first embodiment of a two-dimensional optical switch according to the present invention, Fig. 1(a) is a perspective view thereof, and Fig. 1(a) is a perspective view thereof.
b) is an enlarged sectional view taken along the line A-A in FIG. 1(a);
Fig. 2 is a structural diagram of an interference type (Matsuhatsu Enda type) optical switch, which is a typical optical switch, Fig. 3 is a perspective view showing the first conventional example, and Fig. 4 is a perspective view showing the second conventional example. , 5th
The figure is a perspective view showing the third conventional example, FIG. 6(a) is a perspective view showing the fourth conventional example, FIG. 6(b) is an explanatory diagram of the operating principle of the fourth conventional example, and FIG. The figures show a second embodiment of the two-dimensional optical switch according to the present invention, and FIG. 7(a) is a perspective view thereof, and FIG. FIG. 8, which is an enlarged sectional view in the viewing direction, is a perspective view showing a third embodiment of the two-dimensional optical switch according to the present invention. In the figure, 10-1.1.0-2...lens array, 20
... Optical switch section, 2] ... Board, 22-1 to 22-
9... Optical waveguide type optical switch, Ml... First mirror, M2... Second mirror L-11 to L19 L-
11~L-19-L21-L-29...Lens, 30
...Polarizing plate, 40...Analysis plate. Patent applicant: Agent for Nippon Telegraph and Telephone Corporation
Patent Attorney Yoshi 1) Many years

Claims (2)

[Claims] (1) A two-dimensional optical switch comprising a lens array and an optical switch section formed by arranging a plurality of optical waveguide type optical switches that switch or block the optical path of light transmitted through the lens array, each of the optical switches described above. A first optical waveguide is arranged such that its waveguide axis is substantially perpendicular to the light transmission direction of the lens array, and a first optical waveguide is provided at one end of the optical waveguide to reflect the transmitted light of the lens array and make it enter the optical waveguide. Place the mirror of
A two-dimensional optical switch characterized in that a second mirror is disposed on the other end side to reflect the light emitted from the optical waveguide in a direction substantially perpendicular to the direction of light emitted from the optical waveguide. (2) An optical switch section consisting of a lens array, a polarizing plate, and a plurality of optical waveguide type optical switches that rotate the plane of polarization of light transmitted through these lens arrays and polarizing plates, and each switch in the optical switch section. In a two-dimensional optical switch equipped with an analyzer plate that transmits only light with a rotated plane of polarization, the optical waveguide of each optical switch is arranged such that the waveguide axis thereof is approximately perpendicular to the light transmission direction of the lens array and the polarizing plate. At the same time, a first mirror is arranged on one end side of the optical waveguide to reflect the transmitted light of the lens array and the polarizing plate and make it enter the optical waveguide, and a first mirror is arranged on the other end side to reflect the light transmitted from the optical waveguide. A two-dimensional optical switch characterized in that a second mirror is disposed to reflect the emitted light and make it enter the analyzer plate.