JP5012855B2 - Optical device - Google Patents

Description

  The present invention, for example, in a WDM (Wavelength Division Multiplexing) transmission system, a wavelength selective optical switch (λ-SW) that switches an optical path for each wavelength, and an optical level adjuster (AGEQ: Automatic Gain Equalizer) that equalizes the optical level of each wavelength. The present invention relates to an optical device suitable for use as an optical device.

In recent years, large-capacity WDM transmission systems have been introduced in order to cope with the rapid increase in data traffic due to the spread of the Internet.
In the future, when a photonic network in which WDM transmission systems are connected in a network is formed, a plurality of transmission paths can be taken. Then, it becomes possible to effectively use the limited transmission capacity by allocating a line intensively to a transmission route having a high demand depending on a time zone. In the WDM transmission system, this can be realized by switching the transmission path for each wavelength. Here, the wavelength selective optical switch is an indispensable device.

  In a long-distance WDM transmission system, amplification is repeated by an optical fiber amplifier. However, the optical level of each wavelength becomes non-uniform due to the wavelength dependence of the amplifier gain. The gain of the optical fiber amplifier has a property of concentrating on a wavelength having a high light intensity, and the non-uniformity of the light level is increased every time it passes through the amplifier. In order to prevent this, it is necessary to make the light level of each wavelength uniform, and an optical level adjuster capable of adjusting the attenuation for each wavelength is inserted in the transmission path.

  FIG. 20 is a schematic diagram showing a first conventional example (see Non-Patent Document 1) according to the above-described wavelength selective optical switch. As shown in FIG. 20, a wavelength selective optical switch 910 as a first conventional example is a combination of four waveguide-type diffraction gratings (AWGs) 911 to 914 and an optical switch 919. A 2 × 2 switch having one port (input port 915 and add port 916 on the input side, and output port 917 and drop port 918 on the output side) is configured.

  In the wavelength selective optical switch shown in FIG. 20, the light that has been wavelength-demultiplexed via the two AWGs 911 and 912 on the input side is subjected to a through / switch process in the path by the optical switch 919, and the output side One of the two combined AWGs 913 and 914 is distributed. That is, two AWGs 911 and 912 are used to demultiplex the wavelength multiplexed light from the two ports 915 and 916 on the input side, and the light whose path is switched by the optical switch 919 is sent to the two ports on the output side. The remaining two AWGs 913 and 914 out of the four AWGs are used to output the wavelength multiplexed light from 917 and 918, respectively.

FIG. 21 is a schematic diagram showing a second conventional example (see Patent Document 1) according to the wavelength selective optical switch. In the wavelength selective optical switch 920 shown in FIG. 21, the input WDM light is guided to the switch 923 through the optical fiber 922 after wavelength demultiplexing by the AWG 921, and is combined by the AWG 921 to the port corresponding to the switched optical fiber 922. Wave output.
FIG. 22A is a schematic diagram showing a conventional example (see Patent Document 2) according to the light level adjuster. In the optical level adjuster 930 shown in FIG. 22A, each light wavelength-demultiplexed by the first AWG 931 is input to a Mach Zehnder Interferometer (MZI) 932 shown in FIG. The light whose intensity is adjusted by the MZI 932 is multiplexed and output by the second AWG 933.

IEICE Vol.82 No.7 pp.746-752 Jul 1999

JP-A-8-46569 JP 2002-250827 A

However, in the wavelength selective optical switch shown in FIG. 20 described above, since the number of AWGs 911 to 914 used is as large as four, there is a problem that the overall size of the wavelength selective optical switch 910 increases.
In the wavelength selective optical switch shown in FIG. 21, the number of AWGs used is one, but it is necessary to connect the substrate forming the AWG 921 and each optical switch 922 with the number of optical fibers corresponding to the number of ports. Therefore, there is a problem that the scale of the apparatus becomes large.

Further, in the optical level adjuster 930 shown in FIG. 22A, since the two AWGs 931 and 932 are used, there is a problem that the size of the entire optical level adjuster becomes large.
The present invention has been devised in view of such a problem, and provides an optical device that functions as a wavelength selective optical switch or an optical level adjuster that can reduce the size (device scale) of the device. For the purpose.

  Therefore, in the optical device of the present invention, P (P is a natural number) first circulators and P first input / output waveguides to which the respective paths from the first circulator are respectively connected are formed at one end. And N (N is a natural number) second input / output waveguides formed at the other end, Q (Q is a natural number) second circulators, and second circulators The Q third input waveguides to which the respective paths are connected are formed at one end and the N fourth input / output waveguides are provided at the other end and the second waveguide type diffraction grating formed at the other end. Transmission and reflection of light propagating through each waveguide between the second input / output waveguide of the first waveguide type diffraction grating and the fourth input / output waveguide of the second waveguide type diffraction grating. N transmission / reflection switches for switching between The first circulator, the first waveguide type diffraction grating, the transmission / reflection switch, the second waveguide type diffraction grating, and the second circulator are arranged in a column.

In this case, each transmission / reflection switch described above can be constituted by a cantilever type mirror.
Furthermore, an optical variable attenuator may be interposed between the first waveguide type diffraction grating and the transmission / reflection switch, or between the transmission / reflection switch and the second waveguide type diffraction grating. Good.
In the optical device of the present invention, M (M is a natural number) circulators and M first input / output waveguides to which the respective paths from the M circulators are respectively connected are formed at one end. A waveguide type diffraction grating in which N (N is a natural number) second input / output waveguides are formed at the other end, and light from the N second input / output waveguides is reflected and reflected. N light intensity adjustment circuits capable of adjusting the light intensity of light are arranged in a column.

  In this case, each of the light intensity adjustment circuits described above is bifurcated by a branching waveguide that branches one of the N second input / output waveguides into two and the branching waveguide. Optical path length difference between two branch waveguides having one end connected to the path, a reflection member formed at the other end of each branch waveguide, and each light propagating through each branch waveguide by the thermo-optic effect And a Mach-Zehnder interference circuit comprising a heater capable of adjusting the frequency.

  Further, each of the light intensity adjusting circuits is divided into a branching waveguide that branches one of the N second input / output waveguides into two, and a path that is branched into two by the branching waveguide. A Mach-Zehnder interference circuit comprising two branch waveguides having one end connected to each other and a reflection member formed at the other end of each branch waveguide, and the reflection member of the Mach-Zehnder interference circuit is You may comprise by the piston operation | movement type mirror which can adjust each optical path length difference between said reflection member and a branching waveguide.

  Furthermore, the optical device of the present invention is a waveguide type in which an input waveguide and an output waveguide that are parallel to each other are formed at one end, and 2 × N (N is a natural number) input / output waveguides are formed at the other end. Of the 2 × N input / output waveguides adjacent to the diffraction grating, light from one input / output waveguide for propagating light from the input waveguide is emitted from the output waveguide. N light intensity adjustment circuits that can be introduced into the other input / output waveguide serving as an optical path for adjusting the light intensity and can adjust the light intensity are arranged in a column.

In this case, each light intensity adjusting circuit described above is a Mach-Zehnder interference circuit capable of adjusting the light intensity by adjusting the optical path length difference between the branches by the thermo-optic effect for the light from the one input / output waveguide. An optical circuit that folds back the light whose light intensity is adjusted by the Mach-Zehnder interference circuit so as to be introduced into the other input / output waveguide may be used.
Further, each of the light intensity adjustment circuits described above can be constituted by a lens and a tilt type mirror, and the tilt type mirrors that constitute each of the light intensity adjustment circuits can be integrated as a mirror array.

Thus, according to the optical device of the present invention, the wavelength selective optical switch can be formed by the first and second optical circulators, the first and second waveguide type diffraction gratings, and the transmission / reflection switch, There is an advantage that it is possible to realize a wavelength selective optical switch in which the scale of the apparatus is reduced as compared with the prior art without the need for fiber connection or the like.
In addition, according to the optical device of the present invention, an optical level adjuster can be configured only by using a single waveguide type diffraction grating. There is an advantage that the device can be configured.

  Furthermore, according to the optical device of the present invention, since an optical level adjuster can be configured only by using a single waveguide type diffraction grating, the optical level adjustment with a larger apparatus size than before is possible. There is an advantage that the device can be configured.

It is a schematic diagram which shows the optical device concerning 1st Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 1st Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 1st Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 1st Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 1st Embodiment. It is a schematic diagram which shows the optical device concerning the modification of 1st Embodiment. (A), (b) is a schematic diagram which shows the optical device concerning 2nd Embodiment. It is a schematic diagram which shows the optical device concerning the modification of 2nd Embodiment. It is a schematic diagram which shows the optical device concerning 3rd Embodiment. It is a schematic diagram which shows the optical device concerning the modification of 3rd Embodiment. It is a schematic diagram which shows the optical device concerning 4th Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 4th Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 4th Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 4th Embodiment. It is a schematic diagram which shows the optical device concerning 5th Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 5th Embodiment. It is a schematic diagram which shows the principal part of the optical device concerning 5th Embodiment. It is a schematic diagram which shows the optical device concerning 6th Embodiment. It is a schematic diagram which shows the optical device concerning the modification of 6th Embodiment. It is a schematic diagram which shows a prior art. It is a schematic diagram which shows a prior art. (A), (b) is a schematic diagram which shows both prior arts. (A), (b) is a schematic diagram which shows AWG as a component of an optical device.

Embodiments of the present invention will be described below with reference to the drawings.
(A) Description of Waveguide Type Diffraction Grating The optical device according to the present embodiment functions as a wavelength selective optical switch or an optical level adjuster. As constituent elements of this optical device, FIG. Two types of AWGs 1 and 1A shown in FIG. 23B can be applied. Hereinafter, AWG applied to the optical device in each embodiment of the present invention will be described.

  The AWG 1 in the mode shown in FIG. 23A is provided with one multiplexing-side waveguide 3 as a waveguide for inputting and outputting optical signals. A circulator 2 is connected. The AWG 1 includes a slab waveguide 4, a plurality of channel waveguides 5, slab waveguides 6 having different lengths, and N (N is a plurality) demultiplexing side waveguides 7 together with the input / output waveguide 3 described above. -1 to 7-N are formed on the substrate.

  That is, when wavelength multiplexed light is incident on the multiplexing-side waveguide 3 through the optical circulator 2, the incident wavelength multiplexed light is diffused in the slab waveguide 4 and channel waveguides arranged in parallel in the order of length. When the light is emitted to 5, a phase difference is generated according to each length, and the light is emitted to the slab waveguide 6. In the slab waveguide 6, the wavelength-division multiplexed light in which the phase difference is generated interferes and propagates through the demultiplexing side waveguide 7 that is different for each wavelength.

  As a result, for example, when N-wavelength multiplexed light is incident from the multiplexing-side waveguide 3, the incident N-wavelength multiplexed light is demultiplexed in each of the N demultiplexing-side waveguides 7. Each demultiplexed light can be propagated. In addition, when light having different wavelengths is incident from the respective demultiplexing side waveguides 7-1 to 7-N, contrary to the above case, the incident wavelengths in the multiplexing side waveguide 3 are combined. Waved wavelength multiplexed light can be propagated.

  The optical circulator 2 outputs the light incident from the IN (input) port 2A to the multiplexing-side waveguide 3 of the AWG 1, and the light from the multiplexing-side waveguide 3 passes through the OUT (output) port 2B. It is for output. Thus, when wavelength multiplexed light is input from the IN port 2A, wavelength separation light is obtained in the demultiplexing side waveguide 7, and when light having different wavelengths is input from the demultiplexing side waveguides 7-1 to 7-N, OUT Wavelength multiplexed light for the input light is obtained from the port 2B, and one AWG 1 can be used for both multiplexing and demultiplexing.

  FIG. 23B shows an AWG 1A having a resolution twice that of the AWG 1 shown in FIG. 23A. The AWG 1A has two multiplexing side guides compared to the AWG 1 shown in FIG. The difference is that 2 × N (2 times N) demultiplexing side waveguides 7a-1 to 7a-N, 7b-1 to 7b-N are provided together with the waveguides 3a and 3b. In FIG. 23B, the same reference numerals as those in FIG. 23A denote the same parts.

In addition, the above-described two multiplexing-side waveguides 3a and 3b are arranged close to each other, and the two waveguides 7a-i and 7b-i (i: any integer in 1 to N) are Corresponding to the multiplexing-side waveguides 3a and 3b, they are formed so as to be close to each other.
In the following, when a × b or a × b is described as described above, the number or the number of objects corresponding to the number or number of objects should be equal to the product of the values of a and b. Is shown.

Thereby, for example, the wavelength multiplexed light input to the multiplexing side waveguide 3a is converted into the demultiplexing side waveguides 7a-1 to 7a-N (demultiplexing side waveguides 7a-1 to 7a-N, 7b-1 to 7b-). It is possible to demultiplex and output from an odd-numbered waveguide from the top in the N array.
Similarly, the wavelength multiplexed light input to the multiplexing-side waveguide 3b is transmitted to the demultiplexing-side waveguides 7b-1 to 7b-N (demultiplexing-side waveguides 7a-1 to 7a-N, 7b-1 to 7b-N). (Even waveguides from the top in the arrangement) can be demultiplexed and output.

Furthermore, the AWG 1A can be designed so that the wavelength interval Δλ / 2 and the wavelength number 2 × N can be multiplexed / demultiplexed with respect to the WDM light having the wavelength interval Δλ and the wavelength number N. Normally, the slabs on the multiplexing side and the demultiplexing side are designed so that the shapes are congruent. Further, a second waveguide is added to the multiplexing side with an interval equal to the interval between the waveguide rows on the demultiplexing side.
Note that the AWG 1A illustrated in FIG. 23B is provided with two multiplexing-side waveguides 3a and 3b. However, it is possible to use three or more, and in this case, the resolution is three times or more. AWG. Further, by combining an AWG having a double resolution and a circulator, it is possible to realize a multiplexing / demultiplexing function for four AWGs.

(B) Description of First Embodiment FIG. 1 is a schematic diagram showing an optical device according to the first embodiment, and the optical device 10 shown in FIG. 1 can operate as a wavelength selective optical switch, Two optical circulators 11a and 11b that can function as independent input / output ports, an AWG 12, and N reflective optical switches 13-1 to 13-N are arranged in a column.

  Here, the AWG 12 has the same configuration as the AWG 1A shown in FIG. 23B described above, and two first input / outputs to which the respective paths from the two optical circulators 11a and 11b are respectively connected. Waveguides 121a and 121b are formed at one end, and 2 × N (N is a natural number) second input / output waveguides 125a-1 to 125a-N and 125b-1 to 125b-N are formed at the other end. Yes. Note that 122 and 124 are slab waveguides, and 123 is a channel waveguide.

  The N reflective optical switches 13-1 to 13-N are adjacent to each other among 2 × N second input / output waveguides 125a-1 to 125a-N and 125b-1 to 125b-N. This is for reflecting the optical path of each of the two waveguides 125a-i and 125b-i (i: any integer in 1 to N) and switching the return-destination waveguide. Two 2 × 2 optical switches are configured (in the following, when described as an a × b optical switch, the optical switch has a port functioning as an input port, and as an output port) It shows that there are b functioning ports).

  For example, the reflection type 2 × 2 optical switch 13-1 is optically connected to the two second input / output waveguides 125a-1, 125b-1, and the second input / output waveguides 125a-1, 125b-. The light input from any one of the light sources is reflected, and the return waveguide can be selectively switched between the input waveguide as it is and the other waveguide. It has become.

  The light reflected by the reflective 2 × 2 optical switch 13-i is incident again on one of the second input / output waveguides 125 a-i and 125 b-i, respectively, and the slab waveguide 124 and the channel waveguide 123. Further, through the slab waveguide 122, the light is output through the two first input / output waveguides 121a and 121b and the optical circulators 11a and 11b to which the respective paths are connected.

  With such a configuration, when the optical switches 13-1 to 13-N are set to have the optical path of the reflected light as the original waveguide, the light input through the input port 11a-1 of the optical circulator 11a is The light output through the output port 11a-2 of the optical circulator 11a and input through the input port 11b-1 of the optical circulator 11b is output through the output port 11b-2 of the optical circulator 11b.

  On the other hand, in the case where the optical switches 13-1 to 13-N are set so that the optical path of the reflected light is the other waveguide, the light input through the input port 11a-1 of the optical circulator 11a is output from the optical circulator 11b. The light output through the port 11b-2 and input through the input port 11b-1 of the optical circulator 11a is output through the output port 11a-2 of the optical circulator 11a.

The above-described reflection type 2 × 2 optical switches 13-1 to 13-N can be configured in four types as shown in FIGS.
First, as shown in FIG. 2, the reflection type 2 × 2 optical switches 13-1 to 13-N have a variable variable angle such as lenses 131A to 133A and MEMS (Micro Electric Mechanical System) mirrors as shown in FIG. The optical switches 13A-1 to 13A-N may be configured by a mirror (tilt mirror) 134A.

  In FIG. 2, lenses 131 </ b> A and 132 </ b> A are parallel with respect to light that has been transmitted through second input / output waveguides 125 a-1 and 125 b-1 emitted from a PLC (Planer Lightwave Circuit) end surface on which AWG 12 is formed. The lens 133A collects the light collimated by the lenses 131A and 132A so that the light is focused on the surface of the minute angle variable mirror 134A.

  The minute angle variable mirror 134A is configured as a tilt type mirror whose surface position can be changed, and the collimated light collimated by the lenses 131A and 132A is reflected by changing the incident angle of the light incident from the lens 133A. Then, the return waveguide can be switched. The tilt type mirror 134A is usually configured as an integrated mirror array.

The light reflected by the minute variable angle mirror 134A becomes parallel light by the lens 133A and is condensed by the lenses 131A and 132A so as to be focused on the end faces of the corresponding waveguides 125a-1 and 125b-1. It has become.
Thereby, in the optical switch 13A-i as the first aspect, the light input from the second input / output waveguide 125a-i or 125b-i by selectively switching the angle of the minute angle variable mirror 134A. Can be selectively switched from either one of the two second input / output waveguides 125a-i and 125b-i.

The lenses 131A to 133A of the switches 13A-1 to 13A-N described above can be configured by an integrated lens array, and the mirror 134A is also an integrated array of mirrors. Can be configured.
Next, as shown in FIG. 3, the reflection type 2 × 2 optical switches 13-1 to 13-N are configured as a second type of configuration, and the reflection type MZI 13B- integrally formed on the substrate 12A on which the AWG 12 is formed. 1-13B-N.

  Here, each of the MZIs 13B-i shown in FIG. 3 has two branches in the upper and lower sides in the figure in which one ends are connected to two paths from the two-input two-output directional coupler 131B and the directional coupler 131B, respectively. Heating control by the waveguide 137B, the heater 132B that individually heats the branch waveguide 137B that forms the above-described two paths, the electrode 133B that supplies a voltage for heating control to the heater 132B, and the two heaters 132B influence each other. In order to prevent this, a heat insulating groove 134B formed between the branch waveguides 137B and a λ / 4 plate 135B and a reflection film (reflection member) 136B formed at the end of the substrate 12A are provided.

  Focusing on the MZI 13B-1, the directional coupler 131B of the MZI 13B-1 causes the light from the two second input / output waveguides 125a-1 and 125b-1 to interfere with each other and the light reflected by the reflective film 136B. The two input / output waveguides 125a-1 and 125b-1 function as two-input two-output interference waveguides that interfere with each other. Can be propagated to the subsequent stage.

  That is, the light input through the port 11a-1 is input through the waveguide 125a-1, but the optical path is turned upside down and propagates through the lower branch waveguide 137B in the two output paths in the figure. Similarly, the light input through the port 11b-1 is input through the waveguide 125b-1, but the optical path is turned upside down and propagates through the upper branch waveguide 137B in the two output paths in the figure.

The heater 132B is formed on the branch waveguide 137B to which the two paths from the directional coupler 131B are connected, and can adjust the optical path length difference for light propagating through each branch waveguide 137B by the thermo-optic effect. Is.
Specifically, the heater 132B causes a refractive index change by heater heating to each of the two upper and lower branch waveguides 137B, and causes a phase difference between the light propagating through the two branch waveguides 137B. It is something that gives birth.

  The reflection film 136B is connected to the other end of the branch waveguide 137B having two paths and reflects both the two-way light from the branch waveguide 137. The heater 132B is formed by the reflection film 136B. Heater heating of propagating light can be performed in a reciprocating optical path on the branch waveguide 137B. As a result, the power consumption of the heater can be halved as compared with the case where an MZI is formed in which the optical path is not folded by the reflective film 136B.

  Here, when the second input / output waveguides 125a-1 and 125b-1 as output destinations of the light input to the reflective 2 × 2 optical switch 13B-1 are left as they are, two upper and lower branch waveguides are used. The heater heating control is performed so that the phase relationship of the light propagating through 137B becomes the same phase relationship, but when the second input / output waveguides 125a-1 and 125b-1 that are the output destinations of the input light are switched. The heater heating control is performed so that the light propagating through the two upper and lower branch waveguides 137B has an opposite phase relationship with each other.

  Thus, when the light propagating through the upper and lower branch waveguides 137B as the return light is input to the directional coupler 131B, the phase relationship between the two lights is controlled to the same phase by the heater 132B. The return light propagating through the two upper and lower waveguides returns to the original path (second input / output waveguides 125a-1 and 125b-1 which are the same as those at the time of input) again after the optical path is turned upside down. Is output.

On the other hand, when the phase relationship between the two lights is controlled to the opposite phase by the heater 132B, the light propagated in the opposite direction before the reflection by the reflection film 136B does not reverse the optical path upside down. And is output from a path connected to the other second input / output waveguides 125a-1 and 125b-1 different from that at the time of input.
In other words, the phase when combined by reciprocating the optical path in the MZI 13B-1 is controlled by the change in refractive index by heating the heater, and if controlled to the same phase, the upper and lower ports are switched, and if the opposite phase is input Light is returned to the port.

Thereby, in the optical switch 13B-i as the second mode, the heating of the heater 132B through the electrode 133B is controlled, so that the light input from the second input / output waveguide 125a-i or 125b-i The waveguide through which the return light should propagate can be selectively switched from one of the two second input / output waveguides 125a-i and 125b-i.
In addition, the reflection type 2 × 2 optical switches 13-1 to 13-N are configured in the third mode as shown in FIG. 4 in the same manner as the one shown in FIG. 3 (see reference numeral 131B) as shown in FIG. Reflective optical switches 13C-1 to 13C-N each including a directional coupler 131C functioning as two-way waveguide 137C having one end connected to the directional coupler 131C and a piston motion micromirror 132C You can also

  Here, the piston motion micromirror 132C functions as a reflecting member formed at the other end of each branch waveguide 137B. Under the control from the outside, the surface of the mirror 132C is moved back and forth in parallel with the optical path. Thus, a difference can be made in the optical path length between the light reciprocating between the two branch waveguides 137C. In other words, the piston motion micromirror 132C functions as a piston operation type mirror that can adjust the optical path length difference between the directional coupler 131C and the surface of the mirror 132C.

  As a result, when the light propagating through the upper and lower branch waveguides 137C as the return light is input to the directional coupler 131B, the optical path length difference is controlled by the mirror 132C so that these two lights have the same phase. In this case, the return light propagating through the upper and lower waveguides is inverted upside down, and the original path (second input / output waveguides 125a-1, 125b-1 same as those at the time of input) is obtained. ) Again and output.

On the other hand, when the optical path length difference is controlled by the mirror 132C so that the two lights are in opposite phases, the light propagated in the reverse path before the reflection by the mirror 132C The signal is output without being reversed upside down, and is output from a path connected to the other second input / output waveguides 125a-1 and 125b-1 different from those at the time of input.
Therefore, in the optical switch 13C-i as the third mode, the light input from the second input / output waveguide 125a-i or 125b-i is adjusted by adjusting the mirror surface position of the mirror 132C in parallel with the optical path. By adjusting the optical path length difference for the first and second input / output waveguides 125a-i or 125b-i, the two input / output waveguides 125a-i , 125b-i can be selectively switched.

In addition, the reflection type 2 × 2 optical switch 13-i (i: any integer from 1 to N) can return the above-described configuration by utilizing the magneto-optical effect as shown in FIG. A reflective 2 × 2 optical switch 13D-i configured to switch the previous waveguide may be used.
Here, the reflection type 2 × 2 optical switch 13D-i shown in FIG. 5 includes two collimators 131D and a plurality of duplexers 131D corresponding to the two paths connected to the second input / output waveguides 125a-i and 125b-i. A refracting plate 132D, a λ / 2 plate (half-wave plate) 133D, a birefringent plate 134D, a lens 135D, and an MO (Magneto Optic) medium-attached mirror 136D are provided.

In addition, the two collimators 131D collimate each light input from the second input / output waveguides 125a-i and 125b-i and emit the light to the second input / output waveguides 125a-i and 125b-i, respectively. It collimates the return light.
Furthermore, the birefringent plates 132D and 134D propagate with different refractive indexes in the longitudinally polarized light and the transversely polarized light among the incident light, and respectively transmit the light from 125a-i and 125b-i to each other. The λ / 2 plate 133D can separate the polarization components propagating through different optical paths and combine the polarization components incident on the different optical paths. Is output as longitudinal polarization, and when the input light is longitudinal polarization, it is output as transverse polarization.

  The lens 135D condenses the light from the birefringent plate 134D and reflects it to the MO medium-equipped mirror 136D, and condenses the light reflected by the MO medium-equipped mirror 136D and emits it to the birefringent plate 134D. It is. Further, the MO-attached mirror 136D is obtained by fixing the MO medium 136D-2 on the surface of the mirror 136D-1 that reflects the light from the lens 135D, and gives magnetic energy to the MO medium 136D-2. Thus, the polarization of the reflected light can be rotated 0 degree or 90 degrees.

  In the reflection type 2 × 2 optical switch 13D-i having such a configuration, for example, light from the second input / output waveguide 125a-i is decomposed into a longitudinally polarized wave and a horizontally polarized wave by the birefringent plate 132D. The wave is converted into longitudinal polarization through the λ / 2 plate 133D. In the birefringent plate 134D, the longitudinally polarized wave separated from the birefringent plate 132D and the longitudinally polarized wave from the λ / 2 plate 133D are emitted to the lens 135D through different optical paths.

  The two longitudinally polarized waves from the birefringent plate 134D are collected by the lens 135D and enter the M / O medium 136D-2. This M / O medium 136D-2 rotates the polarization of the light reflected by the mirror 136D-2 by controlling the applied magnetic field by 0 degrees or 90 degrees. At this time, for the M / O medium 136D-2, the applied magnetic field is controlled so that the rotation of the polarization is 0 degree, so that the reflected light remains in the longitudinal polarization and the propagation path is reversed. The output can be output to the original second input / output waveguide 125a-i.

The light from the second input / output waveguide 125b-i is converted into two transversely polarized waves by the birefringent plate 132D and the λ / 2 plate 133D, but the polarization rotation is 0 degree. By controlling the applied magnetic field, it is possible to output the reflected light to the original second input / output waveguide 125b-i while maintaining the transverse polarization.
On the other hand, the vertical polarization from the second input / output waveguides 125a-i and 125b-1 is controlled by controlling the applied magnetic field with the polarization rotation of 90 degrees with respect to the M / O medium 136D-2. Since the wave and the transverse polarization are switched and reflected, the output destination waveguide is replaced with the input waveguide and output. That is, the reflected light of the light from the waveguide 125a-i is output from the waveguide 125b-i, and the reflected light of the light from the waveguide 125b-1 is output from the waveguide 125a-i.

  Therefore, in the optical switch 13D-i as the fourth aspect, the polarization of the reflected light is rotated to 0 degree or 90 degrees by controlling the magnetic field applied to the M / O medium 136D-2, so that the second The waveguide in which the return light of the light input from the input / output waveguides 125a-i or 125b-i should propagate is selectively switched from one of the two second input / output waveguides 125a-i and 125b-i. be able to.

  With the above-described configuration, in the optical device 10 according to the first embodiment, assuming that the ports 11a-1 and 11b-1 are add ports and imports, and the ports 11a-2 and 11b-2 are drop ports and out ports, respectively. Only by using a single AWG, it can be operated as a switch for performing ADM (Add / Drop Multiplexing) switching.

  That is, in order to output light of a predetermined wavelength from the wavelength multiplexed light input from the import 11b-1 from the outport 11b-2, the optical path of the corresponding wavelength is switched so that the reflected light follows the original optical path. The optical switch 13-i is controlled. As a result, the reflected light is output from the out port 11b-2 through the multiplexing-side waveguide 121b and the optical circulator 11b.

  In addition, in order to output light of a predetermined wavelength from the wavelength multiplexed light input from the import 11b-1 from the drop port 11a-2, light for switching the optical path of the corresponding wavelength so that the reflected light follows the other optical path. The switch 13-i is controlled. As a result, the reflected light is output from the drop port 11a-2 through the multiplexing-side waveguide 121a and the optical circulator 11a. By similarly controlling the optical switch 13-i, it is possible to output light of a predetermined wavelength from the add port 11a-1 to the out port 11b-2.

Furthermore, in the optical switches according to the second to fourth aspects, if both the ports 11a-1 and 11b-1 are imported and the ports 11a-2 and 11b-2 are both outports, a single AWG is used. It is possible to operate as a switch for performing wavelength cross-connect only by using
As described above, according to the optical device of the first embodiment, it is possible to configure the wavelength selective optical switch in which the apparatus scale is significantly reduced as compared with the conventional configuration while using a single AWG as a component. There are advantages.

  In addition, according to the optical device to which the reflective optical switches 13B-1 to 13B-N according to the second aspect are applied, the PLC in which the single AWG and the optical switches 13-1 to 13-N are formed on the same substrate. Thus, it is possible to form a wavelength selective optical switch, and to realize a wavelength selective optical switch with a reduced device scale while reducing the number of AWGs used as device constituent elements as compared with those according to the prior art. There are advantages you can do.

  The reflective optical switches shown in FIGS. 2 to 5 are all 2 × 2 optical switches. For example, the constituent elements of the switches shown in FIGS. 2 to 5 are tree-connected in multiple stages. Thus, an optical switch having two or more ports in input / output can be configured. In this way, an optical device as a wavelength selective optical switch can be configured to have two or more ports in input / output.

(B1) Description of Modification of First Embodiment FIG. 6 is a schematic diagram showing an optical device 10A according to a modification of the first embodiment. In the optical device 10A shown in FIG. Compared to the optical device 10 shown, the optical variable attenuation for variably controlling the intensity of light propagating between the second input / output waveguides 125a-i and 125b-i of the AWG 12 and the reflective optical switch 13-i. The difference is that VOAs (VOA: Variable Optical Attenuator) 14a-i and 14b-i are interposed. In FIG. 6, the same reference numerals as those in FIG. 1 denote the same parts.

As the VOAs 14a-i and 14b-i, for example, basically in the same manner as the optical switch 13B-i shown in FIG. 3, the optical path of light propagating between the branch waveguides using the refractive index change caused by the heater heating. It can be configured by MZI that controls the length difference.
According to the optical device 10A having such a configuration, the number of AWGs using the wavelength selective optical switch having a function as an AGEQ for adjusting the level of the light intensity between the wavelengths and equalizing it as an apparatus component is the conventional technology. Therefore, there is an advantage that it can be realized while reducing the scale of the apparatus significantly.

(C) Description of Second Embodiment FIG. 7A is a schematic diagram showing an optical device according to the second embodiment, and the optical device 20 shown in FIG. 7 can operate as a wavelength selective optical switch. Two AWGs 21 and 22 similar to those shown in FIG. 23A (see reference numeral 1) are provided, and the demultiplexing side waveguides (second input / output waveguides) 217-1 to 217 of the AWG 21 are provided. -N (N is a natural number of 2 or more) and the demultiplexing side waveguides (fourth input / output waveguides) 227-1 to 227 -N of the AWG 22 are respectively connected via cantilever type MEMS mirrors 23-1 to 23 -N. It is connected.

  The first circulator 24 is connected to the multiplexing-side waveguide (first input / output waveguide) 213 of the AWG 21, and the third circulator 25 is connected to the multiplexing-side waveguide (third input / output waveguide) 223 of the AWG 22. Is connected. In other words, the first circulator 24, the AWG 21, the cantilever type MEMS mirrors 23-1 to 23-R, the AWG 22, and the second circulator 25 are arranged in a column.

  In the AWG 21, one first input / output waveguide 213 to which a route from the first circulator 24 is connected is formed at one end, and N second input / output waveguides 217-1 to 217-N are formed. Functions as a first waveguide type diffraction grating formed at the other end, and the AWG 22 has one third input waveguide 223 connected to the path from the second circulator 25 formed at one end. The N fourth input / output waveguides 227-1 to 227-N function as a second waveguide type diffraction grating formed at the other end.

Further, the cantilever type MEMS mirrors 23-1 to 23-N interposed between the demultiplexing side waveguides 217-1 to 217-N and the demultiplexing side waveguides 227-1 to 227-N, respectively. These function as transmission / reflection switches for switching between transmission and reflection of light propagating through the respective waveguides 217-1 to 217 -N and 227-1 to 227 -N.
FIG. 7B is a diagram showing a schematic diagram for explaining the operation of the above-described cantilever type MEMS mirror 23-i (i: any natural number from 1 to N), and shows the light shown in FIG. 4 is a front sectional view of demultiplexing side waveguides 217-i and 227-i in the device 20. FIG. Reference numeral 27 denotes a clad layer surrounding the waveguides 217-i and 227-i.

As shown in FIG. 7B, the cantilever type MEMS mirror 23-i includes a double-sided mirror 231 and a bar 232 having a mirror end fixed to one end thereof, and the other end of the bar 232 is connected to the waveguide 217-. It is fixed to the cladding layer 27 above i, 227-i.
Further, the mirror 231 is dropped into the groove-like space 28 provided between the two demultiplexing side waveguides 217-i and 227-i. For example, by controlling the application of static electricity, The free end side (the side on which the mirror 231 is fixed) is warped so that the mirror 231 can be lifted from the groove-like space 28.

  Thereby, in a state where the mirror 231 is dropped into the groove-shaped space 28, the two demultiplexing side waveguides 217-i and 227-i are blocked, and the light from the demultiplexing side waveguide 217-i is The light reflected from the one surface of the mirror 231 is reflected toward the original waveguide 217-i, and the light from the demultiplexing side waveguide 227-i is reflected from the other surface of the mirror 231 to the original waveguide 227. It will be reflected towards -i.

When the mirror 231 is lifted from the groove-like space 28, the two demultiplexing side waveguides 217-i and 227-i are optically connected, and the light from the demultiplexing side waveguide 217-i is While propagating through the waveguide 227-i, light from the demultiplexing side waveguide 227-i propagates through the waveguide 217-i.
With the above configuration, in the optical device 20 according to the second embodiment, the port 24-1 on the side input to the first optical circulator 24 is imported, and the port 25-1 on the side input to the second optical circulator 25 is imported. Two AWGs are formed when an add port is used, and a port 24-2 output from the first optical circulator 24 is an out port, and a port 25-2 output from the second optical circulator 25 is a drop port. A switch that performs ADM (Add / Drop Multiplexing) switching can be configured with a single PLC.

  That is, in order to output light having a predetermined wavelength from the wavelength multiplexed light input from the import 24-1, the output port 24-2 outputs the demultiplexed light of the corresponding wavelength (propagating the demultiplexed light). By arranging the mirror 231 of the cantilever type MEMS mirror 23-i provided at the terminal end of the demultiplexing side waveguide 217-i in the groove-shaped space 28, the light of the wavelength is demultiplexed. Reflect to i. As a result, the reflected light is output from the out port 24-2 through the multiplexing-side waveguide 213 and the first optical circulator 24.

  Further, in order to output light of a predetermined wavelength from the wavelength multiplexed light input from the import 24-1, the cantilever type provided on the extension of the optical path in the demultiplexed light of the corresponding wavelength is output from the drop port 25-2. By lifting the mirror 231 of the MEMS mirror 23-i from the groove-shaped space 28, the light of the wavelength is output to the demultiplexing side waveguide 227-i. The light output to the demultiplexing side waveguide 227-i is output from the drop port 25-2 through the multiplexing side waveguide 223 and the second optical circulator 25. By similarly controlling the cantilever type MEMS mirror 23-i, light of a predetermined wavelength can be output from the add port 25-1 to the out port 24-2.

Further, if both ports 24-1 and 25-1 are imported and ports 24-2 and 25-2 are both outports, wavelength cross-connect is performed with a single PLC in which two AWGs are formed. It can be operated as a switch.
As described above, according to the optical device 20 according to the second embodiment, the first and second optical circulators 24 and 25, the two AWGs 21 and 22, and the cantilever type MEMS mirrors 23-1 to 23-N are used. There is an advantage that it is possible to form a switch, and it is possible to realize a wavelength selective optical switch in which the scale of the apparatus is reduced as compared with the prior art without the need for connection by an optical fiber or the like.

In particular, a wavelength selective optical switch can be formed by a single PLC (Planer Lightwave Circuit) in which two AWGs and cantilever type MEMS mirrors 23-1 to 23-N are formed on the same substrate. There is an advantage that it is possible to realize a wavelength selective optical switch whose device scale is greatly reduced.
In the optical device 20 shown in FIG. 7A, the two AWGs 21 and 22 are provided with one multiplexing-side waveguides 213 and 223, so that the optical device 20 is configured as a 2 × 2 wavelength selective optical switch. However, the present invention is not limited to this, and the number of the multiplexing-side waveguides of the AWGs 21 and 22 is P (P: a natural number of 2 or more) and Q (Q: a natural number of 2 or more), respectively. It is also possible to configure a wavelength selective optical switch having two or more ports in input / output.

The cantilever-type MEMS mirror 23-functions as a transmission / reflection switch for switching between transmission and reflection of light propagating through the respective waveguides 217-1 to 217 -N and 227-1 to 227 -N. Those other than 1 to 23-N may be used.
(C1) Description of Modification of Second Embodiment FIG. 8 is a schematic diagram showing an optical device 20A according to a modification of the second embodiment. In the optical device 20A shown in FIG. Light propagating on the demultiplexing side waveguides 217-1 to 217-N of the AWG 21 and on the demultiplexing side waveguides 227-1 to 227-N of the AWG 22 as compared with the optical device 20 shown in a). The difference is that variable optical attenuators (VOA) 28-1 to 28-N, 29-1 to 29-N for variably controlling the intensity of light are interposed. In FIG. 8, the same reference numerals as those in FIG. 7 denote the same parts.

As the VOAs 28-1 to 28-N and 29-1 to 29-N, for example, the refractive index change caused by the heater heating is used in the same manner as the optical switches 13B-1 to 13b-N shown in FIG. Thus, it can be configured by MZI that controls the optical path length difference of light propagating between the branch waveguides.
According to the optical device 20A having such a configuration, it is possible to realize a wavelength selective optical switch having a function as an AGEQ that adjusts and equalizes the light intensity between wavelengths while greatly reducing the scale of the apparatus. There is an advantage that can be.

  The VOAs 28-1 and 28-N described above are provided on the demultiplexing side waveguides 217-1 to 217-N, but at least between the AWG 21 and the cantilever MEMS mirrors 23-1 to 23-N. The VOAs 29-1 to 29-N may be provided at least between the AWG 22 and the cantilever type MEMS mirrors 23-1 to 23-N. It is good also as providing in the location which propagates the emitted light.

(D) Description of Third Embodiment FIG. 9 is a schematic view showing an optical device according to the third embodiment. The optical device 30 shown in FIG. 9 is compared with the optical device 10 in the first embodiment described above. The optical switches 33-1 to 33-N using the cantilever type MEMS mirrors 331a and 331b are applied as the reflection type optical switches 13-1 to 13-N, and other configurations are different. Basically the same. In FIG. 9, the same reference numerals as those in FIG. 1 denote the same parts.

  Here, the reflection type optical switch 33-i (i: any natural number from 1 to N) can propagate demultiplexed light having the same wavelength (two adjacent) second input / output waveguides 125a-i, An optical circuit 332 that turns back light from one waveguide in 125b-i so as to be introduced into the other waveguide, and light that propagates through two adjacent second input / output waveguides 125a-i and 125b-i And two cantilever type MEMS switches 331a and 331b for switching between transmission and reflection.

  Here, the optical circuit 332 shown in FIG. 9 includes a reflecting mirror 332a, and two adjacent second input / output waveguides 125a-i and 125b-i are connected to the second input / output waveguide 125a-. i, 125b-i is formed such that light from one waveguide is reflected by the reflection mirror 332a and introduced into the other waveguide. The second input / output waveguides 125a-i and 125b-i may be connected (bypass) using bent waveguides or the like.

  With the configuration described above, in the optical device 30 according to the third embodiment, the port 11b-1 on the side input to the optical circulator 11b is imported, the port 11a-1 on the side input to the optical circulator 11a is an add port, When the port 11b-2 on the side output from the circulator 11b is an out port and the port 11a-2 on the side output from the optical circulator 11a is a drop port, the ADM (Add / Drop) is configured with a single AWG. Multiplexing switching can be configured.

  That is, in order to output light of a predetermined wavelength from the wavelength multiplexed light input from the import 11b-1 from the out port 11b-2, the cantilever type in the optical switch 33-i for switching the optical path of the corresponding wavelength By disposing the MEMS mirrors 332a and 332b in a groove-like space (not shown), the light having the wavelength propagating from the demultiplexing side waveguide 125b-i is reflected to the demultiplexing side waveguide 125b-i. As a result, the reflected light is output from the out port 11b-2 through the multiplexing-side waveguide 121b and the optical circulator 11b.

  In order to output light of a predetermined wavelength from the wavelength multiplexed light input from the import 11b-1 from the drop port 11a-2, a cantilever type in the optical switch 33-i for switching the optical path of the corresponding wavelength By lifting the MEMS mirrors 332a and 332b from a groove-like space (not shown), the light of the wavelength propagating from the demultiplexing side waveguide 125b-i is output to the demultiplexing side waveguide 125a-i. The light output to the demultiplexing side waveguide 125a-i is output from the drop port 11a-2 through the multiplexing side waveguide 121a and the optical circulator 11a.

Further, by similarly controlling the cantilever type MEMS mirrors 332a and 332b of the optical switch 33-i, it is possible to output light having a predetermined wavelength from the add port 11a-1 to the out port 11b-2.
As described above, according to the optical device according to the third embodiment, a wavelength selective optical switch can be formed with a configuration using a single AWG, and the number of AWGs used as device components is reduced to the prior art. There is an advantage that it is possible to realize a wavelength selective optical switch with a reduced device scale by eliminating the need for optical fiber connection or the like inside the switch while reducing the amount of the optical fiber.

(D1) Description of Modification of Third Embodiment FIG. 10 is a schematic view showing an optical device 30A according to a modification of the third embodiment. In the optical device 30A shown in FIG. Compared with the optical device 30 shown, optical variable attenuation for variably controlling the intensity of light propagating between the second input / output waveguides 125a-i and 125b-i of the AWG 12 and the reflective optical switch 33-i. The difference is that VOAs (VOA: Variable Optical Attenuator) 14a-i and 14b-i are interposed. In FIG. 10, the same reference numerals as those in FIG. 9 denote the same parts.

As the VOAs 14a-i and 14b-i, for example, similar to the one shown in FIG. Can be configured.
According to the optical device 30A having such a configuration, the number of AWGs using the wavelength selective optical switch having a function as an AGEQ for adjusting and equalizing the light intensity level between wavelengths as the apparatus constituent element is the conventional technology. Therefore, there is an advantage that it can be realized while reducing the scale of the apparatus significantly.

(E) Description of Fourth Embodiment FIG. 11 is a schematic diagram showing an optical device 40 according to the fourth embodiment. The optical device 40 shown in FIG. 11 can operate as an optical level adjuster. The AWG 41 similar to that shown in FIG. 23A is provided, and a multiplexing-side waveguide formed at one end of the AWG 41 [first input / output waveguide, reference numeral 3 in FIG. Reference] In 413, an optical circulator 42 is a demultiplexing side waveguide formed on the other end of the AWG 41 [second input / output waveguide, see reference numerals 7-1 to 7-N in FIG. 23A] 417- Reflected light intensity adjusting elements 43-1 to 43-N are connected to 1 to 417-N, respectively.

In AWG 41, 414 is a slab waveguide corresponding to reference numeral 4 in FIG. 23A, 415 is a channel waveguide corresponding to reference numeral 5 in FIG. 23, and 416 is a slab waveguide corresponding to reference numeral 6 in FIG. It is.
That is, the optical circulator 42, the AWG 41, and the N reflected light intensity adjustment elements 43-1 to 43-N that can function as input / output ports are arranged in a column.

The reflected light intensity adjusting elements 43-1 to 43-N reflect the light from the demultiplexing side waveguides 417-1 and 417-N and can adjust the light intensity of the reflected light. It functions as an intensity adjustment circuit, and can be configured, for example, in any of the modes shown in FIGS.
That is, the reflected light intensity adjusting elements 43-1 to 43-N have a reflection type MZI (Mach-Zehnder interference circuit) 43A- integrally formed with the PLC forming the AWG 41 as shown in FIG. 1-43A-N.

Here, all of the reflective MZIs 43A-1 to 43A-N have the same configuration, and when focusing on the reflective MZI 43A-1 corresponding to the reflected light intensity adjusting element 43-1, the branched waveguide 431 is obtained. And two branch waveguides 432a and 432b, reflecting members 433a and 433b, and heaters 434a and 434b.
In other words, the branching waveguide 431 of the MZI 43A-1 branches the branching-side waveguide 417-1 in two, and the two branching waveguides 432a and 432b are two branches by the branching waveguide 431. The reflecting members 433a and 433b are formed at the other ends of the respective branch waveguides 432a and 432b, and reflect the light propagating through the respective branch waveguides 432a and 432b. is there.

  Furthermore, the heaters 434a and 434b can adjust the optical path length difference for each light propagating through the branch waveguides 432a and 432b by the thermo-optic effect. For example, as in the case shown in FIG. Electrodes (see reference numeral 133B) are provided to supply heating control voltages to 434a and 434b, respectively, and branch waveguides 432a and 434a and 434a and 434b You may make it form a heat insulation groove | channel between 432b.

Thereby, the reflected light propagating through the branch waveguides 432a and 432b, the phase difference of which has been adjusted by the heaters 434a and 434b, is multiplexed while interfering with the branch waveguide 431. In other words, by adjusting the phase difference of the reflected light before multiplexing in the heaters 434a and 434b, the light level at the time of multiplexing can be adjusted.
Therefore, in the reflection type MZI 43A-1 to 43A-N as the configuration of the first aspect of the reflected light intensity adjusting elements 43-1 to 43-N, the AWG 41 is adjusted by adjusting the phase of the reflected light using the thermo-optic effect. The level of reflected light propagating through the demultiplexing side waveguides 417-1 to 417-N can be adjusted.

The reflected light intensity adjusting elements 43-1 to 43-N may be reflective MZIs (Mach-Zehnder interference circuits) 43B-1 to 43B-N as shown in FIG.
Here, all of the reflection type MZI 43B-1 to 43B-N have the same configuration. When attention is paid to the reflection type MZI 43B-1 corresponding to the reflected light intensity adjusting element 43-1, the above-described MZI 43A- In addition to the branch waveguide 431 and the two branch waveguides 432a and 432b similar to those in the case of 1, the reflection members 435a and 435b different from the case of the MZI 43A-1 described above (see reference numerals 433a and 433b) are provided. Configured.

The reflecting members 435a and 435b are formed at the other ends of the branch waveguides 432a and 432b, respectively. These reflecting members 435a and 435b are the same as the above-described Biston operation type mirror 132C in FIG. It is comprised by.
Each of the piston operation type mirrors 435a and 435b can be controlled by an external control so that the surfaces of the mirrors 435a and 435b can be moved back and forth in parallel with the optical path. It is possible to make a difference in the optical path length between the light reciprocating through 432b. In other words, the piston operation type mirrors 435a and 435b can adjust the respective optical path length differences between the mirrors 435a and 435b and the branching waveguide 431.

Thereby, the reflected light propagating through the branch waveguides 432a and 432b, whose optical path length difference is adjusted by the piston operation type mirrors 435a and 435b, is multiplexed while interfering with the branch waveguide 431. That is, by adjusting the optical path length difference of the reflected light before the combination in the piston operation type mirrors 435a and 435b, the light level at the time of the combination can be adjusted.
Therefore, in the reflection type MZI 43B-1 to 43B-N as the configuration of the second mode of the reflected light intensity adjustment elements 43-1 to 43-N, the optical path length difference adjustment of the reflected light is performed using the piston operation type mirrors 435a and 435b. By performing the above, it is possible to adjust the level of reflected light propagating through the original demultiplexing side waveguides 417-1 to 417-N in the AWG 41.

Furthermore, the reflected light intensity adjusting elements 43-1 to 43-N can be lens mirror mechanisms 43C-1 to 43C-N as shown in FIG. 14 as the configuration of the third mode.
Here, the lens mirror mechanisms 43C-1 to 43C-N all have the same configuration, and attention is paid to the lens mirror mechanism 43C-1 corresponding to the reflected light intensity adjusting element 43-1. The mechanism 43C-1 includes a lens 436 and a minute angle variable mirror (tilt mirror) 437 such as a MEMS mirror.

  The lens 436 can condense the light emitted from the PLC end face on which the demultiplexing side waveguides 417-1 to 417-N forming the AWG 41 are formed. The light collected by these lenses 436 Is incident on a mirror 437. In other words, the lens 436 of the lens mirror mechanism 43C-1 optically couples the light emitted from the demultiplexing side waveguide 417-1 and the tilt mirror 437.

The mirror 437 reflects the light incident from the lens 436, and is configured so that the angle of the reflection surface can be adjusted. As a result, the amount of light reflected from the lens 436 to the lens 436 can be reduced. It can be changed. The tilt mirror 437 is usually configured as an integrated mirror array.
Therefore, in the lens mirror mechanisms 43C-1 to 43C-N as the configuration of the third aspect of the reflected light intensity adjusting elements 43-1 to 43-N, the amount of reflected light is adjusted by adjusting the reflection surface position of the tilt mirror 437. Can be adjusted to adjust the level of reflected light propagating through the original demultiplexing side waveguides 417-1 to 417-N in the AWG 41.

  In the optical device 40 configured as described above, the wavelength multiplexed light from the input port 42-1 connected to the optical circulator 42 is wavelength-separated by the AWG 41, and in the demultiplexing side waveguides 417-1 to 417-N. Propagates as light of individual wavelengths. Each of the reflected light intensity adjusting elements 43-1 to 43-N reflects the light from the demultiplexing side waveguides 417-1 to 417-N and adjusts the level of the reflected light, thereby adjusting the light intensity of each wavelength. Equalize. Thereby, the light with the equalized level of each wavelength component is multiplexed by the AWG 41 and output from the output port 42-2 through the multiplexing side waveguide 413 and the optical circulator 42.

As described above, according to the optical device 40 according to the fourth embodiment, an optical level adjuster can be configured only by using a single AWG 41. There is an advantage that a level adjuster can be configured.
(F) Description of Fifth Embodiment FIG. 15 is a schematic diagram showing an optical device 50 according to the fifth embodiment. The optical device 50 shown in FIG. 15 can operate as an optical level adjuster. An AWG 51 similar to that shown in FIG. 23B is provided.

  Further, at one end of the AWG 51, there are a multiplexing side waveguide 513b as an input waveguide and a multiplexing side waveguide 513a as an output waveguide [refer to reference numerals 3b and 3a in FIG. 23B, respectively]. At the other end of the AWG 51, a demultiplexing side waveguide [2 × N input / output waveguides, reference numerals 7a-1 to 7a-N, 7b-1 to 7b-N in FIG. Reference] 517a-1 to 517a-N and 517b-1 to 517b-N are formed, and the reflected light intensity adjusting element 53-i is connected to each of the two adjacent demultiplexing side waveguides 7a-i and 7b-i. ing.

In AWG 51, 514 is a slab waveguide corresponding to reference numeral 4 in FIG. 23B, 515 is a channel waveguide corresponding to reference numeral 5 in FIG. 23, and 516 is a slab waveguide corresponding to reference numeral 6 in FIG. It is. That is, the AWG 51 and the N reflected light intensity adjustment circuits 53-1 to 53-N are arranged in a column.
Each of the reflected light intensity adjusting elements 53-1 to 53-N adjusts the light intensity of the light from the demultiplexing side waveguides 517b-1 and 517b-N as one of the input / output waveguides, and the light intensity is increased. It functions as a light intensity adjustment circuit that reflects the adjusted light and introduces it into the demultiplexing side waveguides 517a-1 to 517a-N as the other input / output waveguides. It can comprise in the aspect shown in either of FIG.

  That is, the reflected light intensity adjusting elements 53-1 to 53-N are configured as a light intensity adjusting circuit including an MZI (Mach-Zehnder interference circuit) 531 and a mirror 532 as shown in FIG. it can. Here, the light intensity adjustment circuits 53A-1 to 53A-N all have the same configuration, and in the following, the light intensity adjustment circuit 53A-1 corresponding to the reflected light intensity adjustment element 53-1. The structure will be described by paying attention to.

Here, the MZI 531 constituting the light intensity adjusting circuit 53A-1 can adjust the optical path length difference between the branches by using the thermo-optic effect for the demultiplexed light propagated through the demultiplexing side waveguide 517b-1 constituting the AWG 51. The branch waveguide 531a, the two branch waveguides 531b and 531c, the combined waveguide 531d, and the heaters 531e and 531f are provided.
That is, the branching waveguide 531a of the MZI 531 branches the demultiplexed light propagating through the branching-side waveguide 517b-1, and the two branching waveguides 531b and 531c are branched into two by the branching waveguide 531a. One end is connected to each of the paths, and the combined waveguide 531d combines light propagating through the branch waveguides 531b and 531c as light propagating through one waveguide 517b-1.

  Furthermore, the heaters 531e and 531f can adjust the optical path length difference for each light propagating through the respective branch waveguides 531b and 531c by the thermo-optic effect. For example, as in the case shown in FIG. Electrodes (refer to reference numeral 133B) are provided to supply heating control voltages to 531e and 531f, respectively, and branch waveguides 531b and 531b are provided to prevent the heating control by the two heaters 531e and 531f from affecting each other. You may make it form a heat insulation groove | channel between 531c.

As a result, the light propagating through the branch waveguides 531b and 531c, the phase difference of which has been adjusted by the heaters 531e and 531f, is multiplexed while interfering with the multiplexing waveguide 531d. In other words, by adjusting the phase difference of the reflected light before multiplexing in the heaters 531e and 531f, the light level at the time of multiplexing can be adjusted.
Further, the mirror 532 reflects the light whose light intensity is adjusted by the MZI 531 and introduces it into the demultiplexing side waveguide 517a-1, and the adjacent demultiplexing side waveguides 517a-1 and 517b-1 Of these, for the light from one of the demultiplexing side waveguides 517b-1 (propagating the light from the input waveguide 513a), the other demultiplexing side waveguide (being an optical path for emitting from the output waveguide) An optical circuit that is folded back to be introduced into 517a-1 is configured.

Therefore, in the light intensity adjustment circuits 53A-1 to 53A-N as the configuration of the first aspect of the reflected light intensity adjusting elements 53-1 to 53-N, the phase of the reflected light is adjusted by using the thermo-optic effect. The level of each wavelength forming the output light in the AWG 51 can be adjusted.
The MZI 531 described above is arranged so as to adjust the intensity of the demultiplexed light before being reflected by the mirror 532, but may be arranged so as to adjust the intensity of the reflected light after being reflected by the mirror 532.

Further, the reflected light intensity adjusting elements 53-1 to 53-N can be lens mirror mechanisms 53B-1 to 53B-N as shown in FIG. 17 as the configuration of the second mode.
Here, the lens mirror mechanisms 53B-1 to 53B-N all have the same configuration, and attention is paid to the lens mirror mechanism 53B-1 corresponding to the reflected light intensity adjusting element 53-1. The mechanism 53B-1 includes lenses 536a to 536c and a minute angle variable mirror (tilt mirror) 537 such as a MEMS mirror.

The lens 536b can collimate the light emitted from the PLC end surface on which the input / output waveguide 517b-1 is formed into parallel light. The lens 536c is a minute angle variable mirror 537 for the light collimated by the lens 536b. While condensing so that a focal point may come on the surface, the reflected light from the mirror 537 is condensed into parallel light.
The mirror 537 reflects the light incident from the lens 536c, and is configured so that the angle of the reflection surface position can be adjusted. As a result, the amount of light reflected from the lens 536c to the lens 536c is reduced. It can be changed. The tilt mirror 537 is usually configured as an integrated mirror array.

Further, the lens 536a condenses the reflected light collected by the lens 536c so that the reflected light is focused on the PLC end surface on which the input / output waveguide 517a-1 is formed. In other words, the lenses 536a to 536c of the lens mirror mechanism 53B-1 optically couple the AWG 51 and the tilt mirror 537.
Therefore, in the lens mirror mechanisms 53C-1 to 53C-N as the configuration of the third aspect of the reflected light intensity adjusting elements 53-1 to 53-N, the amount of reflected light is adjusted by adjusting the reflection surface position of the tilt mirror 537. By adjusting the level of the reflected light, the level of the reflected light propagating through the original demultiplexing side waveguides 517-1 to 517-N in the AWG 51 can be adjusted.

  In the optical device 50 configured as described above, the wavelength multiplexed light from the input waveguide 513b is wavelength-separated by the AWG 51 and propagates as light of individual wavelengths in the demultiplexing side waveguides 517b-1 to 517b-N. . In each of the reflected light intensity adjusting elements 53-1 to 53 -N, the light levels from the demultiplexing side waveguides 517 b-1 to 517 b -N are adjusted and reflected so that the demultiplexing side waveguides 517 a-1 to 517 a. Equalizes the light intensity of each wavelength propagating through -N. As a result, the light with the equalized level of each wavelength component is multiplexed by the AWG 51 and outputted from the output port 42-2 through the multiplexing side waveguide 413 and the optical circulator 42.

As described above, also in the optical device 50 according to the fifth embodiment, an optical level adjuster can be configured only by using a single AWG 51, so that the optical level of which the apparatus size is greatly increased as compared with the conventional device. There is an advantage that the regulator can be configured.
(G) Description of Sixth Embodiment FIG. 18 is a schematic diagram showing an optical device 60 according to the sixth embodiment, and the optical device 60 shown in FIG. 18 can operate as a wavelength selective optical switch. AWGs 62 and 64 having the same configuration as that shown in FIG. 23B are arranged in tandem, and N reflective optical switches 63-1 to 63-N are interposed between the AWGs 62 and 64. . That is, the above-described AWG 62, optical switches 63-1 to 63-N, and AWG 64 are arranged in a column on the substrate 61.
Here, in the AWG (first waveguide type diffraction grating) 62 shown in FIG. 18, 621a and 621b are two input waveguides (refer to reference numerals 3a and 3b in FIG. 23B), respectively, and 625a-1 to 625a-1. Reference numerals 625a-N and 625b-1 to 625b-N denote 2 × N output waveguides (see reference numerals 7a-1 to 7a-N and 7b-1 to 7b-N in FIG. 23B). That is, the wavelength multiplexed light input through the input waveguides 621a and 621b can be demultiplexed, and the demultiplexed light can be propagated through the output waveguides 625a-1 to 625a-N and 625b-1 to 625b-N, respectively. It is like that.

  Further, the optical switch 63-i (i: an arbitrary natural number from 1 to N) is provided with two output routes together with two input routes, and the 2 × N output waveguides 625a− described above. 1 to 625a-N and 625b-1 to 625b-N are connected to the adjacent two waveguides 625a-i and 625b-i, and the input light from the input path is connected. The output route to be output can be switched, and is configured as a 2 × 2 optical switch. The two output paths of these optical switches 63-i are connected to the input waveguides 645a-i and 645b-i of the AWG 64.

  In the AWG (second waveguide type diffraction grating) 64, 645a-1 to 645a-N and 645b-1 to 645b-N are 2 × N input waveguides (reference numeral 7a-1 in FIG. 23B). -7a-N, 7b-1 to 7b-N], 641a and 641b are two output waveguides [see 3a and 3b in FIG. 23 (b)], respectively. That is, the demultiplexed lights input through the input waveguides 645a-1 to 645a-N and 645b-1 to 645b-N can be multiplexed and propagated as wavelength multiplexed light through the output waveguides 641a and 641b, respectively. It is like that.

Here, the optical switches 63-1 to 63-N described above are configured as MZI type optical switches as shown in detail in FIG. The optical switches 63-1 to 63-N have a configuration in which the MZIs 13B-1 to 13B-N in the first embodiment described above are developed as MZIs in one direction.
Here, the 2 × 2 optical switch 63-i shown in FIG. 18 is connected to two paths from the directional coupler 631 and the directional coupler 131B having two inputs and two outputs. The two branch waveguides 632a and 632b and the other ends of the branch waveguides 632a and 632b are provided with a two-input two-output directional coupler 634 connected to the two input paths, and the two paths described above are formed. Heaters 635a and 635b for individually heating the branch waveguides 632a and 632b, and electrodes 637a and 637b for supplying a heating control voltage to the heaters 635a and 635b are provided.

Further, two output paths of the directional coupler 634 are adjacent to the corresponding two of the 2 × N input waveguides 641a-1 to 641a-N and 641b-1 to 641b-N in the AWG 64. The waveguides 641a-i and 641b-i are connected.
In order to prevent heating control by the two heaters 635a and 635b from affecting each other, a heat insulating groove 636 is formed between the branch waveguides 632a and 632b.

  Thereby, also in the 2 × 2 optical switch 63-i, by controlling the heating of the heaters 635a and 635b through the electrodes 637a and 637b, the phase difference of the light propagating through the branch waveguides 632a and 632b is adjusted, The waveguide to which the light input from the output waveguides 625a-i or 625b-i propagates can be selectively switched from one of the two input waveguides 645a-i and 645b-i.

Accordingly, the wavelength components of the wavelength multiplexed light input through the input waveguides 621a and 621b of the AWG 62 are switched in the path by the optical switches 63-1 to 63-N, and wavelength multiplexed through the output waveguides 641a and 641b of the AWG 64. It is output as light.
In the optical device 60 configured as described above, the input waveguides 621a and 621b are used as import and add ports, respectively, and the output waveguides 641a and 641b are used as outports and drop ports, respectively. It can be operated as a switch that performs switching.

As described above, according to the optical device 60 of the sixth embodiment, the first and second waveguide type diffraction gratings 62 and 64 and the optical switches 63-1 to 63-N are provided. There is an advantage that the connection of an optical fiber or the like in the wavelength selective switch can be eliminated, and the scale of the apparatus can be greatly reduced.
In particular, a wavelength-selective optical switch can be formed by a PLC in which two AWGs 62 and 64 and optical switches 63-1 to 63-N are formed on the same substrate, and an optical fiber or the like is connected in the wavelength-selective switch. There is an advantage that the scale of the apparatus can be greatly reduced.

  Note that the optical switches 63-1 to 63-N shown in FIG. 18 are all 2 × 2 optical switches. For example, the constituent elements of the switches shown in FIG. An optical switch having two or more ports in input / output can be configured. In this way, an optical device as a wavelength selective optical switch can be configured to have two or more ports in input / output. In addition to the case where the number of input / output ports is the same, it may be configured differently.

(G1) Description of Modification of Sixth Embodiment FIG. 19 is a schematic view showing an optical device 60A according to a modification of the sixth embodiment. In the optical device 60A shown in FIG. Compared to the optical device 60 shown, the intensity of light propagating between each of the two output paths of the reflective optical switch 63-i and each of the input waveguides 645a-i and 645b-i of the AWG 64 is variable. The difference is that a variable optical attenuator (VOA) 64a-i, 64b-i to be controlled is interposed. In FIG. 19, the same reference numerals as those in FIG. 18 denote the same parts.

As the VOAs 64a-i and 64b-i, for example, basically in the same manner as the optical switch 63-i shown in FIG. 18 described above, an optical path of light propagating between the branch waveguides using a refractive index change caused by heater heating It can be configured by MZI that controls the length difference.
According to the optical device 60A having such a configuration, the number of AWGs using the wavelength selective optical switch having a function as an AGEQ for adjusting the level of the light intensity between the wavelengths and equalizing it as an apparatus constituent element can be reduced. Therefore, there is an advantage that it can be realized while reducing the scale of the apparatus significantly.

(H) Others Regardless of the embodiment described above, various modifications can be made without departing from the spirit of the present invention.
Moreover, if each embodiment is disclosed, it can be manufactured by those skilled in the art.

  As described above, the optical device of the present invention is useful when realizing a WDM optical transmission system, and in particular, a wavelength selection optical switch that switches an optical path for each wavelength, and an optical level adjuster that equalizes the optical level of each wavelength. Suitable for use as

Claims (9)

P (P is a natural number) first circulators;
P first input / output waveguides to which the respective paths from the first circulator are respectively connected are formed at one end, and N (N is a natural number) second input / output waveguides are formed at the other end. A first waveguide type diffraction grating;
Q (Q is a natural number) second circulators,
A second waveguide type in which Q third input waveguides to which the respective paths from the second circulator are respectively connected are formed at one end and N fourth input / output waveguides are formed at the other end. With a diffraction grating,
Between the second input / output waveguide of the first waveguide type diffraction grating and the fourth input / output waveguide of the second waveguide type diffraction grating, transmission and reflection of light propagating through the respective waveguides are performed. N transmission / reflection switches for switching are installed,
An optical device comprising the first circulator, the first waveguide type diffraction grating, the transmission / reflection switch, the second waveguide type diffraction grating, and the second circulator arranged in tandem. .   2. The optical device according to claim 1, wherein each of the transmission / reflection switches is a cantilever type mirror.   An optical variable attenuator is interposed between the first waveguide type diffraction grating and the transmission / reflection switch, or between the transmission / reflection switch and the second waveguide type diffraction grating. The optical device according to claim 1, wherein the optical device is characterized. M (M is a natural number) circulators,
M first input / output waveguides connected to the respective paths from the M circulators are formed at one end, and N (N is a natural number) second input / output waveguides are formed at the other end. A waveguide-type diffraction grating,
N light intensity adjustment circuits that can reflect light from the N second input / output waveguides and adjust the light intensity of the reflected light;
An optical device, characterized in that are arranged in a column.   Each of the light intensity adjusting circuits has one end in a branching waveguide that branches one of the N second input / output waveguides into two and a path that is branched into two by the branching waveguide. The two optical waveguides connected to each other, the reflecting member formed at the other end of each of the optical waveguides, and the optical path length difference can be adjusted for each light propagating through the optical waveguides by the thermo-optic effect. The optical device according to claim 4, comprising a Mach-Zehnder interference circuit comprising a heater.   Each of the light intensity adjusting circuits has one end in a branching waveguide that branches one of the N second input / output waveguides into two and a path that is branched into two by the branching waveguide. The Mach-Zehnder interference circuit includes two branch waveguides connected to each other and a reflection member formed at the other end of each branch waveguide, and the reflection member of the Mach-Zehnder interference circuit includes 5. The optical device according to claim 4, wherein the optical device is constituted by a piston operation type mirror capable of adjusting a difference in optical path length between the reflecting member and the branching waveguide. A waveguide type diffraction grating in which an input waveguide and an output waveguide that are parallel to each other are formed at one end and 2 × N (N is a natural number) input / output waveguides are formed at the other end;
Of the 2 × N input / output waveguides adjacent to each other, an optical path for emitting light from one input / output waveguide for propagating light from the input waveguide from the output waveguide; N light intensity adjustment circuits that can be introduced into the other input / output waveguide and can adjust the light intensity;
An optical device, characterized in that are arranged in a column.   Each of the light intensity adjustment circuits described above adjusts the optical path length difference between branches for the light from the one input / output waveguide by a thermo-optic effect, and the Mach-Zehnder interference circuit capable of adjusting the light intensity, and the Mach-Zehnder interference 8. The optical device according to claim 7, further comprising: an optical circuit that turns back the light whose light intensity is adjusted by the circuit so that the light is introduced into the other input / output waveguide.   Each of the light intensity adjustment circuits is constituted by a lens and a tilt type mirror, and the tilt type mirrors constituting each of the light intensity adjustment circuits are integrated as a mirror array. Item 9. The optical device according to any one of Items 4 to 8.

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