JP2006178207A - Attenuator and optical switching apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an attenuator and an optical switching apparatus that have a simple structure and that jointly have a function for selecting the output of an arbitrary wavelength light from a plurality of output ports. <P>SOLUTION: The attenuator is equipped with: two sets of outputting/discarding means composed of three ports comprising one discarding port and two outputting ports each arranged adjacently to the discarding port; a diffractive means for diffracting incident light in a different direction in accordance with its wavelength; and an output direction adjusting means which outputs to the outputting ports a part of the diffracted light for each wavelength outputted from the diffractive means and which adjusts the output direction of the diffracted light so that the remainder is outputted to the discarding port. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an attenuator device and an optical switching device, and more particularly to an attenuator device and an optical switching device using an inverse dispersion double spectroscope.

  Conventionally, an attenuator device using an inverse dispersion type double spectrometer is known. An inverse dispersion type double spectrometer is sometimes called an inverse dispersion type double monochromator or a zero dispersion spectrometer. In an attenuator device using an inverse dispersion type double spectrometer, wavelength dispersion is performed twice with respect to input light. The action (in the opposite direction) is given in order, and the attenuation operation is performed on the diffracted light after receiving the first wavelength dispersion action and before receiving the second wavelength dispersion action. Then, the second wavelength dispersion action is given to the light after the attenuation operation, and then output to the outside.

In the attenuator device using the inverse dispersion double spectroscope described in Patent Document 1, the attenuation operation is performed using a micromirror array. Specifically, the diameter of each micromirror is smaller than the spot diameter of light (operation target light) incident on the micromirror array, and a large number of micromirrors are arranged in the spot diameter of the operation target light. In addition, a micromirror array is configured. Then, the attenuation operation is performed by inclining a part of the plurality of micromirrors positioned in the spot diameter in a direction different from the output direction and guiding a part of the operation target light to the outside of the optical path, that is, discarding it. Yes. Further, the light discarded at that time is detected by a sensor to monitor spectrum information, and the number of micromirrors tilted in a direction different from the output direction is controlled based on the spectrum information.
JP 2002-196173 A

  As described above, in the attenuator device using the inverse dispersion double spectroscope described in Patent Document 1, the diameter of each micromirror is smaller than the spot diameter of light (operation target light) incident on the micromirror array, and The micromirror array is configured such that a large number of micromirrors are arranged within the spot diameter of the operation target light. For this reason, there exists a problem that the structure of a micromirror array becomes complicated.

Further, only a single output port is assumed, and a function that selectively uses a plurality of output ports is not supported.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an attenuator device and an optical switching device that have a simpler configuration and also have a function of selecting an output of light in an arbitrary wavelength band from a plurality of output ports. Is to provide a device.

  The optical attenuator device according to claim 1 includes two sets of output / discard means comprising three ports, one discard port and two output ports arranged adjacent to each discard port, Diffracting means for diffracting incident light in different directions according to its wavelength, and outputting a part of the diffracted light for each wavelength range outputted from the diffracting means to the output port, and the rest to the discarding port. Output direction adjusting means for adjusting the output direction of the diffracted light.

  The invention according to claim 2 is the attenuator device according to claim 1, wherein only one set of output and output ports each composed of one discarding port and one output port arranged adjacent thereto is provided. A disposal means is further provided.

  The invention according to claim 3 is the attenuator device according to claim 1 or 2, wherein the number of output ports of the attenuator device is n, and the n is an even number. If n / 2 and n is an odd number, (n + 1) / 2 discard ports are provided.

  A fourth aspect of the present invention is the attenuator device according to any one of the first to third aspects, comprising at least three sets of the output / discard ports, and two of the output ports. And an input port for inputting incident light having at least one wavelength component.

The invention according to claim 5 is the attenuator device according to claim 1 or 2, further comprising an output port that does not have an adjacent discard port.
The optical switching device according to claim 6 includes two sets of output / discard means comprising three ports, one discard port and two output ports arranged adjacent to each discard port. An output / discard means, an input port that is arranged adjacent to two of the output ports and receives incident light having at least one wavelength component, and diffracts the incident light in different directions depending on the wavelength First diffracting means, output direction adjusting means for adjusting the output direction of diffracted light for each wavelength range output from the first diffracting means, and diffractive action in the opposite direction to the first diffracting means. A second diffractive means for providing, and the output direction adjusting means adjusts the output direction so that the diffracted light for each wavelength region is directed to any one of the plurality of sets of output / discard means. Both of the above diffracted lights Depending on the intensity and its wavelength range, all of the diffracted light is output to the output port or the discard port, or a part of the diffracted light is output to the output port and the rest is discarded The output direction of the diffracted light is adjusted so as to be output to the production port.

  The optical switching device according to claim 7, wherein an input port for inputting incident light having at least one wavelength component, a plurality of output ports, and a discarding port adjacent to two output ports among the plurality of output ports, The first diffracting means for diffracting the incident light in different directions according to the wavelength, and a plurality of tiltable mirrors corresponding to each of the wavelengths diffracted by the diffracting means, Output direction adjusting means for adjusting the output direction of the diffracted light for each wavelength range output from the diffracting means, and second diffracting means for giving a diffractive action in the opposite direction to the first diffracting means, The output direction adjusting means relates to an axis perpendicular to the arrangement direction of the mirrors when the mirror corresponding to the wavelength toward each of the two input ports adjacent to the discarding port attenuates the wavelength light. Those inclined in axisymmetric directions Te.

  According to the present invention, it is possible to provide an attenuator device and an optical switching device that have a simple configuration and also have a function of selecting an output of light in an arbitrary wavelength band from a plurality of output ports.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 shows a schematic diagram of an attenuator device using an inverse dispersion double spectrometer according to an embodiment of the present invention. As shown in the figure, the attenuator device of this embodiment includes a plurality of optical fibers 1-1 to 1-7, a microlens array 2, a lens 3, lenses 4-1, 4-2, and a diffraction grating 5. , The micromirror array 7, the sensors 8-1, 8-1, the driver 23 for driving the micromirror array 7, and the processor for giving a command to the driver 23 according to the outputs of the sensors 8-1, 8-1 22 and various programs used by the processor 22 and a memory 21 for storing data.

  In FIG. 1, the incident direction of the spectral light L2 to the channel attenuator device is “Z direction”, and the direction orthogonal to the Z direction and parallel to the paper surface is “X direction”. A direction orthogonal to the X direction and the Z direction is defined as a “Y direction”. Therefore, the coordinate system shown in FIG. 1 is a right-handed coordinate system.

  The optical fibers 1-1 to 1-7 allow the light to be split from a light source (not shown) to enter the channel attenuator device (input port), and guide the output light of the channel attenuator device to the outside (output port). Or a member (for example, a single mode fiber) for guiding the output light of the channel attenuator device to the sensors 8-1 and 8-2 (trap port). The diameter of the light emission part of the optical fibers 1-1 to 1-7 is, for example, 10 μm.

  In this embodiment, the optical fiber 1-4 is an input port, the optical fibers 1-1, 1-3, 1-5, 1-7 are output ports, and the optical fibers 1-2, 1-6 are trapped. It is used as a port for use. A light source (not shown) is arranged in front of the optical fiber 1-4 used as an input port.

  Wavelength multiplexed light (wavelength ranges of λ1, λ2,..., Λ6) L1 emitted from the optical fiber 1-4 serving as an input port is collimated by the corresponding microlens 2-4 to become collimated light L2. .

  The optical fibers 1-1, 1-3, 1-5, and 1-7, which are output ports, are disposed adjacent to the trap ports 1-2 and 1-6, respectively. That is, two sets of output / discard ports are configured by the trap port 1-2 and the output ports 1-1, 1-3 adjacent to the trap port 1-2. The trap port 1-6 and the output ports 1-5 and 1-7 adjacent to the trap port 1-6 constitute two sets of output / discard ports. That is, by arranging two output ports so as to sandwich one trap port, two sets of output / discard ports are constituted by three ports. Therefore, in this embodiment, two trap ports are arranged for four output ports. As a result, in the case of the same number of ports, it is possible to obtain more output ports than an arrangement in which only one output port corresponds to one trap port. Further, the input port 1-4 is disposed adjacent to the output ports 1-3 and 1-5 among the four output ports. By arranging in this way, the stroke of each mirror of the micromirror array 7 to be described later can be reduced.

  Sensors 8-1 and 8-2 are connected to the trap ports 1-2 and 1-6. The sensors 8-1 and 8-2 detect the amount of light incident on the trap ports 1-2 and 1-6 and transmit a detection signal to the processor 22.

  The microlens array 2 includes a plurality of microlenses 2-1 to 2-7 arranged corresponding to the optical fibers 1-1 to 1-7, respectively. The microlenses 2-1 to 2-7 have a positive focal length optimized with respect to the NA (numerical aperture) of the optical fibers 1-1 to 1-7. In addition, the microlenses 2-1 to 2-7 are arranged so that their focal positions coincide with the input / output units of the optical fibers 1-1 to 1-7 corresponding to the microlenses 2-1 to 2-7. Therefore, the light emitted from the input port 1-4 is collimated by the corresponding microlens 2-4, and the collimated light incident on the microlenses 2-1 to 2-3 and 2-5 to 2-7 is supported. Incident on the optical fibers (output port, trap port) 1-1 to 1-3, 1-5 to 1-7.

  The collimated light L2 emitted from the microlens 2-4 is incident on the lens 3 to become convergent light L3a, and forms the intermediate image I1 at the focal position of the lens 3. After passing through the focal position, the light beam becomes diffused light L3b and is incident on the lens 4-1 after expanding the beam diameter.

  The lens 4-1 is disposed so as to have the image formation position of the intermediate image I 1 at the focal position. For this reason, the diffused light L3 becomes the light L4 collimated by the lens 4-1. The collimated light L4 is incident on the diffraction grating 5. Here, the wavelength range of the collimated light L4 is λ1, λ2,.

  The diffraction grating 5 imparts a diffractive action to each of the wavelength ranges λ1, λ2,. Here, the diffraction grating 5 is a transmissive planar diffraction grating, in which a large number of grooves elongated in the Y direction are arranged one-dimensionally along a direction parallel to the X direction. The arrangement direction of the numerous grooves corresponds to the wavelength dispersion direction of the diffraction grating 5. In FIG. 1, in order to easily understand the dispersion path of the light beam, only two paths of the light path in the wavelength band λ2 and the path in the wavelength band λ5 among the wavelength bands included in the wavelength multiplexed light L1 are shown. it's shown.

  Now, the collimated light L4 incident on the diffraction grating 5 is dispersed at a specific angle from the diffraction grating 5 according to the wavelength range by the wavelength dispersion action of the diffraction grating 5 described above. Thereby, the collimated light L4 is diffracted by the diffraction grating 5 to different angles for each wavelength region, converted into diffracted light L5 having different diffraction angles for each wavelength region, and incident on the lens 4-2.

  Next, the diffracted light L5 diffracted to different angles for each wavelength region (λ1, λ2,... Λ6) by the diffraction grating 5 is condensed on the micromirror array 7 as convergent light L6 by the lens 4-2. Then, the intermediate image I2 is formed on the micromirror array 7. Here, the imaging position of the intermediate image I2 and the imaging position of the intermediate image I1 are conjugate positions of the optical system constituted by the lens 4-1, the diffraction grating 5, and the lens 4-2.

  The micromirror array 7 is configured so that the convergent light L6 emitted from the lens 4-2 is condensed on the mirror surfaces of the micromirrors 7-1 to 7-6 that are different for each wavelength region, that is, in the wavelength region λ1. The convergent light L6 is condensed on the mirror surface of the micromirror 7-1, the convergent light L6 in the wavelength region λ2 is condensed on the mirror surface of the micromirror 7-2, and so on, and the convergent light in the wavelength region λ6 It arrange | positions so that L6 may be condensed on the mirror surface of the micromirror 7-6.

  The micromirror array 7 is a device in which a plurality of micromirrors 7-1 to 7-6 are arranged along the X-axis direction. As such an apparatus, for example, there is a MEMS (Micro Electro Mechanical Systems) system. The plurality of micromirrors 7-1 to 7-6 have a size larger than the spot diameter of the intermediate image I2 of the convergent light L6 (the diameter of the spectral light L1 at the output portion of the input port 1-4). The size of the micromirrors 7-1 to 7-6 is approximately several tens of μm square to several hundreds of μm square. In addition, the individual micromirrors 7-1 to 7-6 can independently control the tilt angle of the mirror surface by a drive signal from the driver 23.

  The driver 23 converts the reflected light L7 of the convergent light L6 collected on the micromirrors 7-1 to 7-6 into the collimated light L8 via the lens 4-2 in accordance with a command from the processor 22. The inclination angles of the micromirrors 7-1 to 7-6 are adjusted so as to reach the desired region S1 of the diffraction grating 5.

  The position of the desired region S1 on the diffraction grating 5 is determined based on the optical fibers (1-1, 1-2) (1-2, 1-3) (1-5, used as the output port and the trap port). 1-6) It is determined in advance according to the position of the group (1-6, 1-7). The processor 22 uses an optical fiber (1-1, 1) in which reflected light L6 for each wavelength region (λ1, λ2,... Λ6) from the micromirrors 7-1 to 7-6 is used as an output port and a trap port. -2) (1-2, 1-3) (1-5, 1-6) (1-6, 1-7) so as to reach the region S1 determined in advance according to the position of the set. Commands are issued to control the individual tilt angles of the mirrors 7-1 to 7-6.

  Now, the collimated light L8 that has reached the desired region S1 of the diffraction grating 5 is inversely diffracted in the region S1 and becomes wavelength-multiplexed collimated light L9 and travels toward the lens 4-1. Here, the collimated light L9 is parallel to the collimated light L4 incident on the diffraction grating 5.

  Next, the collimated light L9 enters the lens 4-1, and becomes the convergent light L10b to form the intermediate image I1 at the focal position of the lens 4-1. After passing through the focal position, it becomes diffused light L10b, enters the lens 3, is collimated, and becomes collimated light L11.

  Next, the collimated light L11 is microlenses 2-1 to 2-2, which are arranged corresponding to the optical fibers 1-1 to 1-3, 1-5 to 1-7 used as output ports and trap ports. 3, 2-5 to 2-7, and the output ports 1-1, 1-3, 1-5 at the focal positions of the microlenses 2-1 to 2-3, 2-5 to 2-7 1-7 and the light receiving portions of the trap ports 1-2 and 1-6.

  In FIG. 1, a pair of an output port 1-7 and a trap port 1-6 is used as an output port and a trap port for light of λ2. Further, a pair of output port 1-5 and 1-6 as a trap port are used as an output port and a trap port for λ6 light. Then, a part of the collimated light L11 in the wavelength region λ2 is converged by the microlens 2-7 and is incident on the light receiving portion of the output port 1-7 as the converged light L12, and a part of the collimated light L11 in the wavelength region λ6 is The light is converged by the microlens 2-5 and enters the light receiving portion of the output port 1-5 as convergent light L12. On the other hand, the remaining part of the collimated light L11 in the wavelength regions λ2 and λ6 is converged by the microlens 2-6 and is incident on the light receiving unit of the trap port 1-6 as converged light L13. That is, the trap port 1-6 is a discard port common to the two ports of the output ports 1-5 and 1-7.

  The light amount of the light L13 taken into the trap port 1-6 is detected by the sensor 8-2, and a detection signal is sent to the processor 22. The processor 22 sets the inclination angles of the micromirrors 7-1 to 7-6 in a direction in which the light amount indicated by the detection signal from the sensor 8-1 approaches the set value (information regarding the light amount to be discarded) stored in the memory 21. A command for control is generated and output to the driver 23. In response to this, the driver 23 adjusts the inclination angle of the micromirrors 7-1 to 7-6. That is, in this embodiment, feedback control is performed so that predetermined attenuation is applied.

  When one trap port is shared by multiple output ports, and light of multiple wavelengths is incident on one trap port, the angle of each mirror corresponding to each wavelength is tilted while the light is By monitoring the amount of change in intensity and considering only the amount of change, feedback control for the corresponding wavelength can be performed. It is also possible to arrange a spectroscope behind the trap port and monitor the intensity for each wavelength to perform feedback control.

Next, the attenuation operation of the attenuator device according to this embodiment will be described in detail.
FIG. 2 shows an enlarged view of a part including the sensors 8-1 and 8-1, the optical fibers 1-1 to 1-7, and the microlens array 2 of the attenuator device according to this embodiment, toward the output port 1-7. Take light as an example. FIG. 2A shows an optical path when no attenuation is applied, and FIGS. 2B and 2C show an optical path when attenuation is applied.

  As described above, in the channel attenuator device according to the present embodiment, a part of the collimated light L11 emitted from the lens 3 (converged light L13) is adjusted by adjusting the inclination angle of the micromirrors 7-1 to 7-6. Is incident on the trap port 1-6 and incident on the output port 1-7 to attenuate the amount of the convergent light L12 output to the outside.

  When no attenuation is applied, as shown in FIG. 2A, the spectral light L1 incident from the optical fiber 1-4 is collimated by the corresponding microlens 2-4 to become collimated light L2. The collimated light L2 is subjected to spectral action by the diffraction grating 5 in the optical system (not shown) in the subsequent stage (same as in FIG. 1), and is directed by the micromirrors 7-1 to 7-6 for each spectral wavelength range. Affixed. Among the micromirrors 7-1 to 7-6, for example, the mirror corresponding to the wavelength light to be directed to the output port 1-7 is controlled by the reflection angle of the mirror by the driver 23. 7 is inclined so as to be incident on the region S2 of the diffraction grating 5 toward only 7, that is, only on the microlens 2-7. This wavelength light is collimated by the lenses 4-1 and 3 to become collimated light L11. The collimated light L11 is not attenuated but becomes convergent light L12, enters the output port 1-7, and is output to the outside.

  FIG. 2B shows a case where attenuation is applied. The spectral light L1 incident from the optical fiber 1-4 is collimated by the corresponding microlens 2-4 to become collimated light L2. The collimated light L2 is subjected to spectral action by the diffraction grating 5 in an optical system (not shown) in the subsequent stage (similar to FIG. 1) and directed by the micromirrors 7-1 to 7-6 for each spectral wavelength range. Is made. Among the micromirrors 7-1 to 7-6, the mirror corresponding to the wavelength light to be directed to the output port 1-7 has a desired amount of wavelength light of the microlens by controlling the reflection angle of the mirror by the driver 23. The desired amount of wavelength light is applied to the microlens 2-6 so as to be incident on the region S3 positioned in the + X direction as compared to the region S2 toward the 2-7 and the other toward the microlens 2-6. Incident light is tilted to an angle at which the remaining portion is incident on the microlens 2-7. This wavelength light is collimated by the lenses 4-1 and 3 to become collimated light L11. Therefore, a desired amount of the collimated light L11 is incident on the output port 1-7 as the converged light L12 that is attenuated, and is output to the outside. Further, the discarded portion of the collimated light L11 becomes convergent light L13 and enters the trap port 1-6, and the light amount is detected by the sensor 8-2.

  FIG. 2C shows a case where all the desired wavelength light is discarded. The spectral light L1 incident from the optical fiber 1-4 is collimated by the corresponding microlens 2-4 to become collimated light L2. The collimated light L2 is subjected to spectral action by the diffraction grating 5 in an optical system (not shown) in the subsequent stage (similar to FIG. 1) and directed by the micromirrors 7-1 to 7-6 for each spectral wavelength range. Is made. Among the micromirrors 7-1 to 7-6, the mirror corresponding to this wavelength light is such that this wavelength light is directed to the microlens 2-6 and the microlens 2-7 by controlling the reflection angle by the driver 23. Compared to the region S3, it is tilted so as to be incident only on the region S4 located in the + X direction, that is, on the microlens 2-6. In this case, all of the collimated light L11 becomes convergent light L13 by the microlens 2-6 and enters the trap port 1-6, and the amount of light is detected by the sensor 8-2.

Similarly to the above, the light output to the output port 1-5 can be attenuated by the operation in combination with the trap port 1-6.
Here, the direction in which the mirror is tilted to apply attenuation differs between the two output ports 1-5 and 1-7 adjacent to the trap port 1-6. That is, in FIG. 1, in order to attenuate the light of [lambda] 2 toward the output port 1-7, the mirror corresponding to [lambda] 2 is tilted in the clockwise direction. On the other hand, in order to attenuate the light of λ6 toward the output port 1-5, the mirror corresponding to λ6 is tilted counterclockwise. Therefore, when the trap port is shared by the two output ports, and two sets of output / trap ports are configured by the three ports, the light directed to the two output ports is arranged in the mirror alignment direction during attenuation. It is tilted with respect to an axis perpendicular to the axis.

  In this embodiment, the light amount of the light L13 taken into the trap port 1-6 is detected by the sensor 8-2, and a detection signal is sent to the processor 22. The processor 22 sets the inclination angles of the micromirrors 7-1 to 7-6 in a direction in which the light amount indicated by the detection signal from the sensor 8-1 approaches the set value (information regarding the light amount to be discarded) stored in the memory 21. A command for control is generated and output to the driver 23. In response to this, the driver 23 adjusts the inclination angle of the micromirrors 7-1 to 7-6.

  As described above, in this embodiment, two output ports are adjacent to one trap port, and the two output ports share one trap port. The port can be used effectively in the switch device. Therefore, in an optical switching device having a predetermined number of output ports, the total number of ports can be reduced, and in an optical switching device having a total number of ports, the number of output ports can be increased. .

  As described above, taking the optical switch as shown in FIG. 1 as an example, the case where the total number of ports is 7, of which the number of input ports is 1 and the number of output ports is 4, has been described below. An efficient port arrangement will be described.

  The number of optical fibers that can be used (N) is limited by the numerical aperture (NA) of the optical system and the angle at which the micromirror can be rotated. On the other hand, from the side of incorporating and operating this type of device, operating efficiency and expandability can be improved if there are more output ports in one device. Therefore, it is desired to configure an optical switching device with attenuation that can arrange a larger number of output ports by using a compact optical fiber member.

  In an optical switching device, in order to perform attenuation using a predetermined optical fiber as a trap port, the trap port and the output port must be adjacent to each other. In the present invention, output ports are arranged on both sides of the trap port in order to efficiently use the optical fiber. That is, a plurality of one optical fiber set consisting of three ports, that is, an output port, a trap port, and an output port are arranged, and one discard port is shared by two output ports. With this configuration, the port can be used efficiently with a smaller number of optical fibers.

  The input port is preferably arranged in the center of the optical fiber array as much as possible. The reason will be described below. When a micromirror array is configured with a MEMS or the like, each micromirror is in a state (reference position) generally parallel to the arrangement direction of the micromirror array when nothing is controlled.

  FIGS. 3A and 3B are diagrams illustrating the tilt range of the mirror when the central optical fiber among the adjacent optical fibers serves as an input port. (A) shows the tilt state of the micromirror when output to one end of the optical fiber, and (b) shows the tilt state of the micromirror when output to the other end of the optical fiber. Since light input from the input port enters the mirror from a direction perpendicular to the mirror arrangement direction, the mirror rotates to an arbitrary rotation angle within the tilt range (a) to (b), and nothing is controlled. The position of the mirror in the absence (dotted line in the figure), that is, it is distributed to both sides around the reference position.

  On the other hand, (c) and (d) are diagrams showing the tilt range of the mirror when the end optical fiber of the optical fibers is used as an input port. When outputting to an output fiber adjacent to this input port, the micromirror is hardly tilted as shown in (c), but when outputting light to the output port arranged at the other end of the optical fiber, As shown in (d), it is necessary to greatly tilt the mirror. That is, it is necessary to give a very large rotation angle from the reference position where nothing is controlled, which is parallel to the mirror arrangement direction.

  When controlling the direction in which reflected light travels in a MEMS mirror array, the mirror rotation angle stroke is configured to be smaller by controlling the mirror tilt so that it is distributed from a state in which nothing is controlled, rather than rotating it largely to only one side. It is possible to control without difficulty by using an electrode or the like provided on the back surface of the mirror.

  An example in which the role of each optical fiber is allocated in consideration of the above is shown in FIG. 4, FIG. 5, and FIG. FIG. 4 shows the case where N = 5 to 8, FIG. 5 shows N = 9 to 12, and FIG. 6 shows the case where N = 13 to 16, respectively. In the figure, black circles are trap ports, double circles are input ports, white circles are output ports with attenuation, and triangles are output ports without attenuation.

The condition of the number N of optical fibers for arranging the output ports with attenuation most efficiently is when the remainder obtained by dividing N−1 by 3 is zero.
Mod ((N-1) / 3) = 0
That is, N = 7, 10, 13, and 16. At this time, the number n of output ports with attenuation is as follows.

n = 2 ((N-1) / 3)
Further, when N-1 is divided by 3 and is 1, and the number of output ports with attenuation is maximized, one output port without attenuation can be obtained.

  Furthermore, when N-1 divided by 3 is 2, and the number of output ports with attenuation is maximized, there will be no ports without attenuation, but there will be one trap port and one output port. I can do it. When the remainder obtained by dividing N-1 by 3 is obtained as described above, the number n of the output ports with attenuation is an integer part of 2 ((N-1) / 3).

  In other words, when n is the number of necessary output ports to be arranged, in order to construct an optical switch having an attenuation function with the smallest number of optical fibers, when n is an even number, n / 2 traps are used. Since the ports need only be arranged, if there are (n × 3/2) +1 optical fibers, it is possible to configure an optical switch capable of applying attenuation to all output ports. When n is an odd number, if there are (n + 1) × 3/2 + 1 optical fibers, it is possible to configure an optical switch capable of applying attenuation at all output ports.

The embodiment of the present invention has been described above.
In the present embodiment, the output port and the trap port are arranged adjacent to each other, and the tilt angle of the micromirrors 7-1 to 7-6 is controlled to output the collimated light L11 output from the lens 3 for output. The ratio of the convergent light L12 emitted to the port and the convergent light L13 output to the trap port can be adjusted. For this reason, as in the channel attenuator device described in Patent Document 1, the diameter of each micromirror is smaller than the spot diameter of light (operation target light) incident on the micromirror array, and a large number of micromirrors are provided. It is not necessary to configure the micromirror array so as to be arranged within the spot diameter of the operation target light. Therefore, an attenuator device having a simpler configuration can be provided. Further, the amount of discarded light can be monitored with a simple configuration in which a trap port is arranged next to the output port.

  In addition, this invention is not limited to said embodiment, Many deformation | transformation are possible within the range of the summary. For example, in the above embodiment, a transmissive planar diffraction grating is used as the diffraction grating 5, but the diffraction grating 5 may be, for example, a reflective planar diffraction grating. In this case, the lenses 4-1 and 4-2 can be configured by a single lens.

  In this embodiment, the example used for the inverse dispersion type double spectrometer has been described. However, the present invention can also be applied to an optical cross connect, a switching element, and the like. It can also be applied to other widely used spectrometers. Further, instead of the sensors 8-1 and 8-2, a terminator for preventing reflection of light may be attached, and the sensors may be arranged at each output port to which a splitter is attached.

It is a schematic block diagram of the attenuator apparatus which concerns on one Embodiment of this invention. It is an enlarged view of a portion including sensors 8-1 and 8-1, optical fibers 1-1 to 1-7, and a microlens array 2 of an attenuator device according to an embodiment of the present invention. It is a schematic block diagram which shows the relationship between the input port which concerns on one Embodiment of this invention, and the tendency rotation angle of a micromirror. It is an example of arrangement | positioning of the role of the optical fiber which concerns on one Embodiment of this invention. It is an example of arrangement | positioning of the role of the optical fiber which concerns on one Embodiment of this invention. It is an example of arrangement | positioning of the role of the optical fiber which concerns on one Embodiment of this invention.

Explanation of symbols

1-1 to 1-7 optical fiber, 2 to micro lens array, 2-1 to 2-7 micro lens, 3 lens, 4-1, 4-2 lens, 5 diffraction grating, 7 micro Mirror array, 7-1 to 7-7, micromirror, 8-1 to 2-2, sensor.

Claims (7)

Two sets of output / discard means comprising three ports, one discard port and two output ports arranged adjacent to each discard port;
Diffracting means for diffracting incident light in different directions according to its wavelength;
Output direction adjusting means for adjusting the output direction of the diffracted light so as to output a part of the diffracted light for each wavelength range output from the diffracting means to the output port and the rest to the discarding port; An attenuator device comprising:   2. The attenuator device according to claim 1, further comprising only one set of output / discard means comprising two ports, one discarding port and one output port arranged adjacent thereto. When the number of output ports of the attenuator device is n,
3. The attenuator device according to claim 1, wherein the attenuator device has n / 2 ports when n is an even number and (n + 1) / 2 ports when n is an odd number. . Having at least three output / discard ports;
4. The input port according to claim 1, further comprising an input port disposed adjacent to two of the output ports and configured to input incident light having at least one wavelength component. 5. An attenuator device according to claim 1.   The attenuator device according to claim 1, further comprising an output port having no adjacent discard port. An output / discard means including two sets of output / discard means comprising three ports, one discard port and two output ports arranged adjacent to each discard port;
An input port disposed adjacent to two of the output ports for receiving incident light having at least one wavelength component;
First diffracting means for diffracting the incident light in different directions according to its wavelength;
Output direction adjusting means for adjusting the output direction of the diffracted light for each wavelength region output from the first diffracting means;
A second diffractive means for providing a diffractive action opposite to that of the first diffractive means,
The output direction adjusting means adjusts the output direction so that the diffracted light for each wavelength region is directed to any one of the plurality of sets of output / discard means,
Depending on the intensity and wavelength range of each diffracted light, all of the diffracted light is output to the output port or the discarding port, or a part of the diffracted light is output to the output port. The output direction of the diffracted light is adjusted so that the remainder is output to the discarding port. An input port for inputting incident light having at least one wavelength component;
Multiple output ports,
A discard port adjacent to two of the plurality of output ports;
First diffracting means for diffracting the incident light in different directions according to its wavelength;
An output direction adjusting means that has a plurality of tiltable mirrors corresponding to each of the wavelengths diffracted by the diffracting means, and adjusts the output direction of the diffracted light for each wavelength range output from the first diffracting means. When,
Second diffractive means for providing a diffractive action in a direction opposite to that of the first diffractive means,
The output direction adjusting means is configured such that the mirrors corresponding to the wavelengths directed to the two input ports adjacent to the discard port are axisymmetric with respect to an axis perpendicular to the arrangement direction of the mirrors when the wavelength light is attenuated. An optical switching device which is inclined to