JP4493538B2 - Wavelength selective switch - Google Patents

Description

  The present invention relates to a wavelength selective switch that is used in a hub or the like in a large-scale photonic network in which a plurality of WDM networks are connected and can be switched to an arbitrary path for each wavelength.

  In recent years, high-speed access networks having a bandwidth of about several Mbit / s to 100 Mbit / s such as FTTH (Fiber to The Home) and ADSL (Asymmetric Digital Subscriber Line) are rapidly spreading. With this high-speed access network, an environment where broadband Internet services can be enjoyed is being developed, and in order to respond to the increasing demand for communication, the backbone network (core network) has been laid with an ultra-high-capacity optical communication system using wavelength division multiplexing technology. It's getting on.

  On the other hand, in the connection part between the metro network (metro network) and the core network, there is a concern that a bandwidth bottleneck may occur in the connection part due to the limit of the switching capability by electricity. Therefore, a new optical switching node is installed in the metro area, which becomes a bandwidth bottleneck, and a new photonic network architecture that connects directly between the metro network and the core network, which the user directly accesses, in the optical area without any electrical switch. Since the construction is effective, various research and development are being conducted energetically.

  There is a wavelength selective switch as an optical switch module applied to such a node connecting a core network and a metro network. FIG. 13 is a diagram showing a configuration of a conventional wavelength selective switch. The wavelength selective switch 1300 includes an input optical port 1, a diffraction grating 2, a lens 3, a mirror array 4, and a plurality of output optical ports 5 including port numbers # 1 to # 5. Wavelength division multiplexing (WDM) light (light beam) emitted from the light beam is separated into different angular directions by the diffraction grating 2 and then condensed at different positions by the lens 3. At the condensing position, a mirror array 4 composed of M number of variable angle mirrors (MEMS mirrors) corresponding to the number of separated channels is arranged. The micro mirror can change the angle, reflects the incident signal light at a desired angle, and outputs to a plurality of output light ports 5 (any one of # 1 to # 5) arranged at each angular position. Lead. From the plurality of output light ports 5, signal light of any selected wavelength can be emitted (for example, see Patent Document 1 below).

  FIG. 14 is a diagram showing another configuration of a conventional wavelength selective switch. This wavelength selective switch 1400 is different from the configuration shown in FIG. 13 in that a transmission type diffraction grating 12 is used. Other configurations are the same as those in FIG. θ1 is the light dispersion direction (X direction) for each wavelength by the diffraction grating 12, and θ2 is the light reflection direction (Y direction) by the micromirror 4a corresponding to a certain wavelength. These conventional wavelength selective switches have a 1-input N-output (1 × N) wavelength selection function. Conversely, by switching the input and output, it is possible to provide a wavelength selection function of N inputs and 1 output (N × 1).

  FIG. 15 is a diagram for explaining the wavelength selection function of a conventional wavelength selective switch. As shown in the figure, the input WDM light (λ1 to λM) can be output by assigning a plurality of arbitrary wavelengths to the N optical ports of ch1 to chN, respectively, by a 1-input N-output wavelength selective switch. (For example, refer to Patent Document 2 below.)

US Pat. No. 6,549,699 Special table 2003-515187

  In the above-described prior art, a wavelength selection function of 1 input N output (1 × N) or a wavelength selection function of N input 1 output (N × 1) is realized. On the other hand, in an optical transmission system, a function of an optical hub (Hub) is required. FIG. 16 is a diagram illustrating the function of the optical hub. The optical hub has N inputs and N outputs, and has a function of separating an arbitrary wavelength (λ1 to λM) between these N × N input / output ports and switching to an arbitrary port. . In order to obtain this function, 2N wavelength selective switches as described above are required. For this reason, when it was going to comprise an optical hub by a prior art, there existed a problem that an apparatus became large and cost became high.

  In order to solve the above-described problems caused by the prior art, the present invention has a plurality of input ports and a plurality of output ports, and the WDM light input to the input ports can be switched to an arbitrary output port for each channel. An object of the present invention is to provide a wavelength selective switch having a hub function.

In order to achieve the above-described object, a wavelength selective switch according to the present invention includes a plurality of (N) input ports to which wavelength multiplexed optical signals are respectively input and arranged with a predetermined arrangement direction, and a plurality of input ports. A first chromatic dispersion element that divides and emits a plurality of (M) light beams emitted from the input ports according to wavelength along a direction having an angle different from an arrangement direction of the input ports; and the number of the input ports (N) and a number of N × M corresponding to the number of lights (M) separated by the first wavelength dispersion element, and a minute mirror capable of changing the angle of reflection of incident light. A first mirror array; an input-side optical system; and a minute mirror having the same number of N × M as the first mirror array, and the light reflected by the first mirror array is incident thereon. Select the incident light A second mirror array having a minute mirror whose angle can be changed to output from the selected output port, and the light for each wavelength emitted from the second mirror array, and the selected output port An output side comprising: a second wavelength dispersion element to be emitted to the light source; and a plurality (N) of output ports that are arranged to have a predetermined arrangement direction in which light that has passed through the second wavelength dispersion element is incident An optical system, a first lens provided on the light incident side with respect to the first wavelength dispersion element, and a second lens provided on the light emission side with respect to the first wavelength dispersion element. An optical path of light input from the plurality of input ports is output from the plurality of output ports for each arbitrary wavelength , and the input-side optical system and the output-side optical system include the first mirror. One end of the array and the second mirror array The second wavelength dispersion element is disposed in a folded manner, and the second wavelength dispersion element is shared with the first wavelength dispersion element, and the input port and the output port that constitute the input side optical system and the output side optical system, and the output port And the tilt angles of the first wavelength dispersion element, the first lens, and the second lens are made to coincide with the tilt angles with respect to the optical axis of the input side and output side mirror arrays. It is arranged .

  According to the present invention, light input from a plurality of input ports can be output from an arbitrary output port. Furthermore, light input from the input port can be selected for each wavelength and output from any output port. Thereby, it has an input N and an output N, and an arbitrary wavelength can be switched to an arbitrary port.

  The wavelength selective switch according to the present invention achieves the effect of dramatically reducing the size and cost of the hub device by realizing the optical hub function with a single wavelength selective switch.

  Exemplary embodiments of a wavelength selective switch according to the present invention will be explained below in detail with reference to the accompanying drawings.

(Embodiment 1)
FIG. 1-1 is a diagram illustrating a configuration example of a wavelength selective switch according to a first embodiment of the present invention. The wavelength selective switch 100 includes N input fibers 101 constituting an input port and N output fibers 102 constituting an output port arranged in the Y direction, a convex lens 103, and a diffraction grating 104 as a wavelength dispersion element. (A reflection type or a transmission type is possible) and a convex lens 105 is arranged on the optical axis (Z direction), and further on the extension line of the optical axis, a MEMS (Micro Electro Mechanical Systems) substrate 106 (106a, 106a, 106b). The N input fibers 101 and the N output fibers 102 correspond to N input ports and N output ports, respectively.

  The MEMS substrate 106 includes an input side MEMS substrate 106a and an output side MEMS substrate 106b having a similar structure. The surface of the input-side MEMS substrate 106a and the surface of the output-side MEMS substrate 106b are symmetrically arranged so as to form an angle of 45 degrees (90 degrees each other) with respect to the Z direction that is the optical axis. . These MEMS substrates 106a and 106b have a matrix shape in which M micromirrors 107 are arranged in the X direction and N microarrays 107 are arranged in the Y direction. The number M of micromirrors arranged in the X direction corresponds to the number M of channels having wavelengths λ1 to λM separated by the diffraction grating 104, and N corresponds to the number of ports (the number N of input fibers 101 and output fibers 102). These MEMS substrates 106a and 106b are constituted by minute parts using MEMS technology, and the two MEMS substrates 106 (106a and 106b) according to the first embodiment are angles of the minute mirror 107 on the substrate. It has a mechanism to change

  FIG. 1-2 is a side view of the wavelength selective switch 100. The WDM light output from the input port (input fiber 101) is collected by the convex lens 103 and is incident on the diffraction grating 104. The light distributed by the diffraction grating 104 so that the emission direction differs for each wavelength is incident on the micromirror 107 (see FIG. 1-1) having the corresponding wavelength in the MEMS substrate 106a via the convex lens 105. The light reflected from the minute mirror 107 is incident on the minute mirror 107 of the MEMS substrate 106b.

  The light incident on the MEMS substrate 106a is input to the corresponding minute mirror 107 on the MEMS substrate 106a by the position (1-N) of the input fiber 101 to which the light is input and the light channel (1-M). The Similarly, the minute mirror 107 on the MEMS substrate 106b is associated with the position (1 to N) of the output fiber 102 to be output by the light channel (1 to M), respectively. The light reflected by the mirror 107 passes through the convex lens 105, the diffraction grating 104, and the convex lens 103 in this order, and is output to the output fiber 102 corresponding to the position of the minute mirror 107 on the MEMS substrate 106b.

  For example, in FIG. 1-2, the light of a certain channel wavelength input from the first input port (input fiber 101) changes the angle of the minute mirror 107 on the MEMS substrate 106a to produce the first output. The output (solid line) to the port (output fiber 102) and the output (dashed line) to the Nth output port (output fiber 102) can be switched.

  Therefore, by controlling the angles of the micromirrors 107 of the corresponding MEMS substrate 106a and the micromirrors 107 of the MEMS substrate 106b, light of individual channels can be output to the target output port.

  2 and 3 are side views showing another configuration example of the first embodiment. The two MEMS substrates, which are the features of the first embodiment (see FIG. 1-2), are arranged at 45 degrees with respect to the Z direction, and light is directly incident on the MEMS substrate 106b on the output side from the MEMS substrate 106a on the output side. The configuration to be made is the same as in FIGS. 1-1 and 1-2. 2 and 3 show examples of configurations in which the type of convex lens used in the optical path from the input fiber 101 to the output fiber 102 is changed.

  The wavelength conversion switch 120 shown in FIG. 2 includes small convex lenses 200 corresponding to the input fiber 101 and the output fiber 102 instead of the convex lens 103 and the convex lens 105 in the wavelength conversion switch 100 shown in FIG. However, the light is incident on the diffraction grating 104 in parallel. Since light goes straight to the MEMS substrate 106a on the input side, the positions of the input side and the output side of the MEMS substrate 106 (106a, 106b) are opposite to those of the wavelength conversion switch 100 (position rotated 180 degrees in the YZ plane). .

  Similar to the configuration shown in FIG. 1B, in FIG. 2, the light of a certain channel wavelength input from the first input port (input fiber 101) changes the angle of the micromirror 107 on the MEMS substrate 106a. By changing, the output (solid line) to the first output port (output fiber 102) and the output (dashed line) to the Nth output port (output fiber 102) can be switched.

  Similarly to FIG. 2, the wavelength selective switch 130 shown in FIG. 3 also includes a small convex lens 200 (or a lens array) corresponding to each fiber instead of the convex lens 103 of the wavelength conversion switch 100. The convex lens 105 is arranged in the same state as in FIG. 2, and the light is collected before entering the MEMS substrate 106a. The positions of the input side and the output side of the MEMS substrate 106 (106a, 106b) are wavelength conversion switches. 100 and the same position. Both the wavelength selective switch 120 and the wavelength selective switch 130 control the angles of the micromirrors 107 on the corresponding MEMS substrate 106a and the micromirrors 107 on the MEMS substrate 106b for the light of individual channels, as in the wavelength selective switch 100. By doing so, it can be output to the target output port.

  Similar to the configuration shown in FIG. 1B, in FIG. 3, the light of a wavelength of a certain channel input from the first input port (input fiber 101) changes the angle of the micro mirror 107 on the MEMS substrate 106a. By changing, the output (solid line) to the first output port (output fiber 102) and the output (dashed line) to the Nth output port (output fiber 102) can be switched.

  According to the first embodiment, the function as an optical hub can be realized with only one wavelength selective switch, and the size and cost as an optical hub can be dramatically reduced.

(Embodiment 2)
The configuration of the second embodiment is a configuration in which a beam waist is set on a MEMS substrate. FIG. 4A is a diagram of a configuration example of the wavelength selective switch according to the second embodiment of the present invention. The wavelength selective switch 400 has a configuration in which a beam waist is set on two MEMS substrates 106 (106a and 106b). In the wavelength conversion switch 400, N input fibers 101 and N output fibers 102 are arranged side by side in the Y direction, and the convex lens 103, the diffraction grating 104, and the convex lens 105 are arranged on the optical axis (Z direction). .

  Further, the MEMS substrate 106a and the MEMS substrate 106b are arranged on the same plane on the extended line of the optical axis. The same plane indicates that the surface of the MEMS substrate 106a and the surface of the MEMS substrate 106b are arranged at the same surface position and facing the same direction. In the Y direction of the MEMS substrate 106 (106a, 106b), a convex lens 401 and a total reflection mirror 402 are arranged as a reflection optical system, respectively. The MEMS substrate 106 (106a, 106b) uses the same configuration and function as those shown in FIG.

  FIG. 4-2 is a side view of a configuration example of the wavelength selective switch according to the second embodiment. As shown in FIG. 4B, the wavelength selective switch 400 tilts the MEMS substrate 106 (106a, 106b) by 45 degrees with respect to the Z direction, and moves downward in the figure as viewed from the arrangement position of the MEMS substrate 106 (106a, 106b). Arranges a convex lens 401 and a convex total reflection mirror 402 along a direction (Y direction) orthogonal to the optical axis (Z direction). With this arrangement, the light incident on the input-side MEMS substrate 106a is collected by the convex lens 401, is incident on the total reflection mirror 402, and is reflected on the output-side MEMS substrate 106b.

  Here, the convex lens 401 and the total reflection mirror 402 which are the reflection optical system are the light reflected from the minute mirror 107 of the MEMS substrate 106a which is the input side optical system and the minute amount of the MEMS substrate 106b which is the output side optical system. An optical path is formed that continues the optical path of the light incident on the mirror 107. Therefore, the surface of the two MEMS substrates 106 (106a, 106b) and the surface of the total reflection mirror 402 can be set to the beam waist position. The curvature of the total reflection mirror 402 at this time will be described later.

  According to the second embodiment, two MEMS substrates 106 (106a, 106b) can be mounted on the same plane, and the beam waist can be set on both the input side and output side MEMS substrates 106 (106a, 106b). The reflection efficiency at the micromirror 107 can be increased, and the mountability and performance can be improved. As shown in FIG. 4B, when the lens just before the MEMS substrate 106 (106a, 106b) is the convex lens 105, the optical path L1 between the MEMS substrate 106b and the convex lens 105, and between the convex lens 105 and the MEMS substrate 106a. In the optical path L2, there is an optical path difference between them, and the beam waist position cannot be obtained on all surfaces of the MEMS substrate 106. However, the reflection efficiency is not lowered by performing an optical design that increases the tolerance of the beam waist position. It can be.

(Embodiment 3)
FIG. 5A is a diagram of a configuration example of the wavelength selective switch according to the third embodiment of the present invention. FIG. 5B is a side view of the wavelength selective switch, and FIG. 5C is a top view of the wavelength selective switch. In the wavelength selective switch 500, N input fibers 101 and N output fibers 102 are arranged in the Y direction, and a convex lens 103, a diffraction grating 104, a convex lens 105, and a MEMS substrate 106 are arranged on the optical axis. It has a configuration. Here, the surface of the input-side MEMS 106a and the surface of the output-side MEMS 106b are arranged so as to be on the same plane and orthogonal to the optical axis (along the Y direction). The MEMS substrate 106 has the same configuration as that shown in FIG. FIG. 5-3 shows the separation direction of M channels (λ1 to λM).

  In the wavelength selective switch 500, the diffraction grating 104 is a beam waist position where light incident from the input fiber 101 and collected by the convex lens 103 and light reflected by the output MEMS substrate 106b and collected by the convex lens 105 are incident. Only a slit for diffraction is provided. A portion not used as the diffraction grating 104 (substantially lower half in the figure) is provided with a total reflection coating layer 104a as shown in FIG. The curvature of the total reflection coating layer 104a will be described later.

  The light reflected by the input side MEMS substrate 106 a is incident on the total reflection coating layer 104 a of the diffraction grating 104 via the convex lens 105 and is totally reflected. The optical path length L1 between the MEMS substrate 106b and the convex lens 105 and the optical path length L2 between the convex lens 105 and the MEMS substrate 106a can be made equal.

  According to the third embodiment, since the optical path lengths of the optical paths L1 and L2 can be made the same length, unlike the configuration shown in FIG. 4-2, all the regions (micromirrors 107) of the two MEMS substrates 107a and 107b. ) Can set the beam waist.

(Embodiment 4)
FIG. 6A is a diagram of a configuration example of the wavelength selective switch according to the fourth embodiment of the present invention. The wavelength selective switch 600 includes a lens array 601 in which N input fibers 101 and N output fibers 102 are arranged in the Y direction, and individual spherical lenses are arranged for each fiber (port), and a diffraction grating. 103 and a lens 602 having a different focal point for each fiber are arranged on the optical axis (Z direction). Further, the MEMS substrate 106 (106a, 106b) is disposed on the extended line of the optical axis so as to be inclined 45 degrees with respect to the optical axis.

  The MEMS substrate has a configuration in which the surface of the input-side MEMS substrate 106a and the surface of the output-side MEMS substrate 106b are arranged on the same plane. Since the light incident from the input fiber 101 is incident on the MEMS substrate 106a in parallel by the lens array 601, the MEMS substrate 106a and the MEMS substrate 106b are oppositely arranged (on the Y plane) as compared with the case of using a single convex lens. At a position rotated 180 degrees). Further, a convex lens 603 and a total reflection mirror 604 are arranged in parallel with the MEMS substrate 106. The MEMS substrate 106 has the same configuration and function as those shown in FIG. The curvature of the total reflection mirror 604 will be described later.

  As the lens 602, a cylindrical lens (cylindrical lens) is used. The lens 602 collects the light separated for each wavelength by the diffraction grating 1043 shown in FIG. 6A on the micromirrors 107 at different positions in the X direction.

  FIG. 6B is a side view of the wavelength selective switch according to the fourth embodiment. As illustrated, the lens 602 has a predetermined angle with respect to the Y direction so that the optical path length L1 between the lens 602 and the MEMS substrate 106a and the optical path length L2 between the MEMS substrate 106b and the lens 602 are constant. And diagonally. Further, a total reflection mirror 604 used as a reflection surface is arranged in parallel with the surface of the MEMS substrate 106. Thereby, the MEMS substrates 106a and 106b can be arranged on the same plane, and the beam waist can be set in all regions on the MEMS substrates 106a and 106b. Therefore, the wavelength selective switch 600 can cope with the minute MEMS substrate 106 (106a, 106b).

  7 and 8 are side views showing another configuration example of the fourth embodiment. A wavelength selective switch 610 shown in FIG. 7 has a configuration in which the positions of the lenses 602 of the wavelength selective switch 600 are arranged in the Y direction. Although the optical path lengths of the optical path L1 between the lens 602 and the MEMS substrate 106a and the optical path L2 between the MEMS substrate 106b and the lens 602 are different, the lens focal point of each lens 602 is the surface of the MEMS substrate 106 (106a, 106b) ( The one located on the micromirror 107) is used. The wavelength selective switch 620 shown in FIG. 8 has a configuration in which a MEMS substrate 605 is disposed instead of the total reflection mirror 604 of the wavelength selective switch 610 shown in FIG. The wavelength selective switch 610 and the wavelength selective switch 620 can provide the same effects as the wavelength selective switch 600.

  According to the fourth embodiment, the MEMS substrates 106a and 106b can be arranged on the same plane, and the beam waist can be set in all regions on the MEMS substrates 106a and 106b. Therefore, the wavelength selective switch 600 can cope with the minute MEMS substrate 106 (106a, 106b).

(Embodiment 5)
FIG. 9A is a diagram of a configuration example of the wavelength selective switch according to the fifth embodiment of the present invention. On the coordinate axes as shown, the wavelength selective switch 900 has N input fibers 101, N output fibers 102, a convex lens 103, a diffraction grating 104, and a convex lens 105 arranged on the optical axis (Z direction). To do. Furthermore, the MEMS substrate 106a and the MEMS substrate 106b are arranged on the same plane on the extension line of the optical axis (Z direction). A convex lens 603 and a total reflection mirror 604 are provided in parallel to the MEMS substrate 106 a and the substrate 106 on the perpendicular line of the MEMS substrate 106. The above-described optical components are all configured by being inclined at the same angle with respect to the Y direction. The MEMS substrate 106 has the same configuration and function as those shown in FIG.

  FIG. 9-2 is a side view of the wavelength selective switch according to the fifth embodiment. It is the state which looked at FIG. 9-1 from the side. The wavelength selective switch 900 has the same length of the optical path L1 between the MEMS substrate 106b and the convex lens 105 and the optical path L2 between the convex lens 105 and the MEMS substrate 106a by arranging the optical components obliquely with respect to the Y direction. The optical path length can be

  According to the fifth embodiment, the MEMS substrates 106a and 106b can be arranged on the same plane, and the beam waist can be set in all regions on the MEMS substrates 106a and 106b. Therefore, the wavelength selective switch 600 can cope with the minute MEMS substrate 106 (106a, 106b).

(Description of reflective surface)
FIG. 10 is a diagram for explaining the principle of flat reflection. The light incident on the MEMS substrate 106a on the input side is reflected at any position (reflection point Yr) on the reflection surface 1000 by a change in the variable angle θi (angle formed by the MEMS substrate 106 and the micromirror 107) of the micromirror 107 on the MEMS substrate 106a. ) And the relationship is expressed as Yr = f · θi, where f is the lens focal length. When the reflecting surface 1000 is flat, the reflected beam is directed only to the minute mirror 107 that is symmetric with respect to the central axis of the lens 1001 regardless of where the reflecting surface 1000 has a reflecting point. Therefore, arbitrary switching cannot be performed.

  FIG. 11 is a diagram for explaining the principle of curved surface reflection. A curved reflecting surface such as the reflecting surface 1100 is a reflection angle of light on the reflecting surface 1100 (hereinafter referred to as “reflecting point Yr”) depending on a position where light reflected by the input side MEMS substrate 106a is incident (hereinafter referred to as “reflecting point Yr”). The mirror angle θm (referred to as the angle formed by the reflecting surface 1100 and the curved mirror 1101 on the reflecting surface) is different. That is, if the lens focal length f is constant, the position on the output side MEMS substrate 106b where the light reflected by the reflecting surface 1100 is incident is uniquely determined from the mirror angle θm of the reflecting surface 1100. . Therefore, by adjusting the mirror angle θi on the MEMS substrate 106a, the light reflected by the reflecting surface 1100 can be directed to the arbitrary output side MEMS substrate 106b.

  Specifically, to which reflection point on the reflecting surface 1100 the light incident on the input side MEMS substrate 106a is incident can be adjusted by adjusting the mirror angle θi of the MEMS substrate 106a from Yr = f · θi. It is. Further, the shift amount ΔY for allowing the light reflected by the reflecting surface 1100 to enter the desired position of the MEMS substrate 106b can be obtained by ΔY = 2 × f × θm. Therefore, the curvature, θm, of the curved mirror of the reflection surface 1100 is set so that a desired shift amount ΔY can be obtained at the reflection point of the reflection surface 1100 determined by θi.

  From the above, in the wavelength selective switch 400 to the wavelength selective switch 900 according to the second to fifth embodiments, the reflection surface (104a, 402) for switching from the input side MEMS substrate 106a to the output side MEMS substrate 106b. , 604) is preferably a curved surface having an arbitrary curvature.

  FIG. 12 is a diagram for explaining the principle of blazed reflection. As shown in FIG. 12, a stepped (blazed) reflecting surface 1200 having different reflection angles can also be used, and the same function as curved surface reflection can be obtained. In this case, when the number of ports to be switched (number of input fibers and output fibers) is N, it is sufficient to prepare N-1 reflection angles.

  Therefore, in the wavelength selective switch 400 to the wavelength selective switch 900 in the second to fifth embodiments, the light is used as a reflection surface for switching light from the input side MEMS substrate 106a to the output side MEMS substrate 106b. Even if all curved surfaces having an arbitrary curvature are replaced with blazed surfaces, the same effect can be obtained.

  As described above, by using the module on which the wavelength selective switch described in the first to fifth embodiments is mounted, the Nch input of the signal light multiplexed with M types of wavelengths can be changed to the Nch output. It is possible to switch arbitrarily.

(Supplementary note 1) A plurality of (N) input ports to which wavelength multiplexed optical signals are respectively input and arranged with a predetermined arrangement direction;
A first wavelength dispersive element that emits light emitted from each of the plurality of input ports after being separated into a plurality (M) according to wavelengths along a direction having an angle different from a direction in which the input ports are arranged;
The number of the input ports (N) and the number of N × M corresponding to the number of light separated by the first wavelength dispersion element (M), and the reflection direction of the incident light can be changed in angle. A first mirror array having a micromirror, and an input-side optical system,
A micro mirror having the same number of N × M as the first mirror array is provided, the light reflected by the first mirror array is incident, and the angle is changed so that the incident light is output from the selected output port. A second mirror array with free micromirrors;
A second wavelength dispersion element that multiplexes light of each wavelength emitted from the second mirror array and emits the light to a selected output port;
An output-side optical system comprising a plurality of (N) output ports that are incident with light that has passed through the second wavelength dispersion element and are arranged with a predetermined arrangement direction;
A wavelength selective switch, wherein optical paths of light input from the plurality of input ports are output from the plurality of output ports for each arbitrary wavelength.

(Supplementary note 2) The input-side optical system and the output-side optical system are arranged in a manner of folding back with the first mirror array and the second mirror array as one end,
The wavelength selective switch according to appendix 1, wherein the second wavelength dispersion element is shared with the first wavelength dispersion element.

(Supplementary note 3) The wavelength selection according to supplementary note 2, wherein a first lens is provided on the light incident side of the first wavelength dispersion element, and a second lens is provided on the light emission side. switch.

(Additional remark 4) The said 1st lens makes incident light with respect to a said 1st wavelength dispersion element parallel light,
The wavelength selective switch according to appendix 3, wherein the second lens condenses incident light on the micromirrors of the first mirror array.

(Additional remark 5) The said 1st lens consists of a lens group each provided separately corresponding to the optical axis of the light radiate | emitted from the said input port and made to inject with respect to the said output port. 5. The wavelength selective switch according to 4.

(Additional remark 6) The said 2nd lens consists of a lens group each provided corresponding to the optical axis of the light radiate | emitted from the said input port and the said output port, The additional remark 5 characterized by the above-mentioned. Wavelength selective switch.

(Additional remark 7) The arrangement direction of the said input port and the said output port, and the light separation direction by the said 1st wavelength dispersion element and the 2nd wavelength dispersion element are mutually orthogonally crossed mutually The wavelength selective switch according to any one of the above.

(Supplementary note 8) The first mirror array and the second mirror array are MEMS mirrors formed by a MEMS (Micro Electro Mechanical Systems) technique. Wavelength selective switch.

(Supplementary note 9) The supplementary note, wherein the first mirror array and the second mirror array are arranged in a symmetrical position so that each plane is 45 degrees around the optical axis of the light. The wavelength selective switch according to any one of 2 to 8.

(Supplementary Note 10) The first mirror array and the second mirror array are arranged so that their surfaces are the same plane,
Additional remarks 2-8, further comprising a reflection optical system that forms an optical path that connects the light reflected from the first mirror array and the optical path of the light incident on the second mirror array. The wavelength selective switch according to any one of the above.

(Supplementary Note 11) The first mirror array and the second mirror array are arranged such that their surfaces are the same plane and have an angle of 45 degrees with respect to the optical axis of the light,
11. The wavelength selective switch according to appendix 10, wherein the reflection optical system includes a lens disposed in a direction orthogonal to the optical axis and a reflection mirror.

(Supplementary Note 12) The input port, the output port, the first wavelength dispersion element, the first lens, and the second lens constituting the input-side optical system and the output-side optical system. 12. The wavelength selective switch according to appendix 11, wherein the respective tilt angles of the lenses are arranged so as to coincide with tilt angles with respect to an optical axis of the input side and output side mirror arrays.

(Supplementary note 13) The first mirror array and the second mirror array are arranged so that their surfaces are coplanar and have an angle perpendicular to the optical axis of the light,
11. The wavelength selective switch according to appendix 10, wherein the reflection optical system is a reflection mirror formed on a surface of the first wavelength dispersion element other than a diffraction surface that separates the light.

(Supplementary Note 14) The second lens includes a lens group disposed so that the distance between the first mirror array and the second mirror array has the same optical path length. The wavelength selective switch according to appendix 10.

(Supplementary Note 15) The second lens includes a surface of the first mirror array and a lens group having individual focal lengths so that the surface of the second mirror array is in focus. The wavelength selective switch according to appendix 10.

(Supplementary note 16) The wavelength selective switch according to supplementary note 11, wherein the reflection mirror provided in the reflection optical system is a MEMS mirror.

(Additional remark 17) The reflective surface of the reflective mirror provided in the said reflective optical system is a curved surface reflective surface which has a predetermined curvature according to the change angle of the micro mirror of the said mirror array, The additional remark 11 or 13 characterized by the above-mentioned. The wavelength selective switch described in 1.

(Supplementary note 18) The wavelength selective switch according to Supplementary note 11 or 13, wherein a reflection surface of a reflection mirror provided in the reflection optical system is a blazed reflection surface having a reflection angle that varies stepwise.

  As described above, the wavelength selective switch according to the present invention is suitable for an optical hub device that is provided in a node of an optical communication network and switches a path for each wavelength.

It is a figure which shows the structural example of Embodiment 1 of the wavelength selective switch concerning this invention. It is a side view of a wavelength selective switch. 6 is a side view showing another configuration example of the first embodiment. FIG. 6 is a side view showing another configuration example of the first embodiment. FIG. It is a figure which shows the structural example of Embodiment 2 of the wavelength selective switch concerning this invention. It is a side view of a wavelength selective switch. It is a figure which shows the structural example of Embodiment 3 of the wavelength selective switch concerning this invention. It is a side view of a wavelength selective switch. It is a top view of a wavelength selective switch. It is a figure which shows the structural example of Embodiment 4 of the wavelength selective switch concerning this invention. It is a side view of a wavelength selective switch. FIG. 10 is a side view showing another configuration example of the fourth embodiment. FIG. 10 is a side view showing another configuration example of the fourth embodiment. It is a figure which shows the structural example of Embodiment 5 of the wavelength selective switch concerning this invention. It is a side view of a wavelength selective switch. It is a figure explaining the principle of flat reflection. It is a figure explaining the principle of curved surface reflection. It is a figure explaining the principle of blazed reflection. It is a figure which shows the structure of the conventional wavelength selective switch. It is a figure which shows the structure of the conventional wavelength selective switch. It is a figure explaining the wavelength selection function which the conventional wavelength selective switch has. It is a figure explaining the function of an optical hub.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Input optical port 4 Mirror array 5 Several output optical port 100,120,130,400,500,600,610,620,900 Wavelength selection switch 101 Input fiber 102 Output fiber 103,105,401,603 Convex lens 2,12 , 104 Diffraction gratings 106a, 106b, 605 MEMS substrate 107 Micro mirror 200 Small convex lens 402, 604 Total reflection mirror 601 Lens array 3,602 Lens 1101 Curved surface mirror

Claims (8)

A plurality of (N) input ports, each of which receives a wavelength-multiplexed optical signal and is arranged with a predetermined arrangement direction;
A first wavelength dispersive element that emits light emitted from each of the plurality of input ports after being separated into a plurality (M) according to wavelengths along a direction having an angle different from a direction in which the input ports are arranged;
The number of the input ports (N) and the number of N × M corresponding to the number of light separated by the first wavelength dispersion element (M), and the reflection direction of the incident light can be changed in angle. A first mirror array having a micromirror, and an input-side optical system,
A micro mirror having the same number of N × M as the first mirror array is provided, the light reflected by the first mirror array is incident, and the angle is changed so that the incident light is output from the selected output port. A second mirror array with free micromirrors;
A second wavelength dispersion element that multiplexes light of each wavelength emitted from the second mirror array and emits the light to a selected output port;
An output-side optical system comprising a plurality of (N) output ports that are incident with light that has passed through the second wavelength dispersion element and are arranged with a predetermined arrangement direction;
A first lens provided on a light incident side with respect to the first wavelength dispersion element;
A second lens provided on the light exit side of the first wavelength dispersion element;
With
The input-side optical system and the output-side optical system are arranged so as to be folded back with the first mirror array and the second mirror array as one end,
The second wavelength dispersion element is shared with the first wavelength dispersion element,
Each of the input port, the output port, the first wavelength dispersion element, the first lens, and the second lens constituting the input-side optical system and the output-side optical system. The tilt angle is arranged to match the tilt angle with respect to the optical axis of the input side and output side mirror arrays,
A wavelength selective switch, wherein optical paths of light input from the plurality of input ports are output from the plurality of output ports for each arbitrary wavelength. 2. The wavelength selective switch according to claim 1, wherein an arrangement direction of the input port and the output port and a light separation direction by the first wavelength dispersion element and the second wavelength dispersion element are orthogonal to each other. . The first mirror array and the second mirror array are MEMS (Micro Electro Mechanical 3. The wavelength selective switch according to claim 1, wherein the wavelength selective switch is a MEMS mirror formed by a Systems technique. 4. The first mirror array and the second mirror array are arranged at symmetrical positions so that their surfaces are 45 degrees around the optical axis of the light. The wavelength selective switch according to any one of the above. The first mirror array and the second mirror array are arranged so that their surfaces are on the same plane,
The reflective optical system which forms the optical path which makes the light reflected from the said 1st mirror array, and the optical path of the light which injects into the said 2nd mirror array continue, further provided. 5. The wavelength selective switch according to any one of 4 above. The first mirror array and the second mirror array are arranged so that their surfaces are coplanar and have an angle of 45 degrees with respect to the optical axis of the light,
6. The wavelength selective switch according to claim 5, wherein the reflective optical system includes a lens disposed in a direction orthogonal to the optical axis and a reflective mirror. The first mirror array and the second mirror array are arranged such that their surfaces are coplanar and have an angle perpendicular to the optical axis of the light,
6. The wavelength selective switch according to claim 5, wherein the reflection optical system is a reflection mirror formed on a surface of the first wavelength dispersion element excluding a diffraction surface that separates the light. The wavelength selection according to claim 6, wherein the reflection surface of the reflection mirror provided in the reflection optical system is a curved reflection surface having a predetermined curvature corresponding to a deflection angle of the micromirrors of the mirror array. switch.

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