JP2015031787A - Wavelength selection switch and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To align an input and output part for light, or the like, with high accuracy in a wavelength selection switch in which optical axes of incident and exiting light in input and output ports for light are inclined.SOLUTION: A wavelength selection switch includes an input and output part 10 for light, a spectral element, and a light-deflecting element, arranged on a predetermined axial line C. The input and output part 10 for light includes: input and output ports 11, 12 for light, allowing light to be incident and exiting with an optical axis inclined with respect to the predetermined axial line C; and an aligning port 13 allowing light L3 for alignment to be incident and exiting with an optical axis along the predetermined axial line C.

Description

  The present invention relates to a wavelength selective switch and a manufacturing method thereof.

  Patent Document 1 discloses an invention related to a wavelength selective switch (WSS). This wavelength selective switch includes a collimator array, a relay optical system, a wavelength dispersion element, a condensing optical system, and two reflecting mirrors. Two waveguides are provided for each collimator lens included in the collimator array, and two optical input / output ports are formed by each of the two waveguides. The light input / output angles of these light input / output ports are different from each other.

US Patent Application Publication No. 2012/0237218 JP 2011-248000 A US Patent No. 7725027

  The wavelength selective switch has a configuration in which an optical input / output unit, a spectroscopic element, and an optical deflection element are arranged side by side on a predetermined axis. As one form of such a wavelength selective switch, the light input / output unit is divided into two or more groups, and the two or more light deflection units of the light deflection element corresponding to the incident / exit light of each group, for example, a direction intersecting the spectral direction There is a form of arranging them side by side. By adopting such a form, it becomes possible to separate (or combine) more wavelength components as compared with the conventional wavelength selective switch.

  As described above, when two or more light deflecting units are arranged side by side in a direction crossing the spectral direction, each light input / output port is used to allow light from each group of light input / output ports to reach each light deflecting unit. May be inclined with respect to the predetermined axis (see, for example, Patent Document 1). However, if the input / output optical axis of each light input / output port is inclined, alignment work (alignment) of the light input / output unit or the like becomes difficult. That is, in a general wavelength selective switch, the input / output optical axis of the light input / output port is along the predetermined axis, so that the alignment light is input to a certain light input / output port, The light input / output unit or the like may be aligned so that the light intensity of the return light is increased (that is, the optical axis of the return light and the optical axis of the light input / output port are close to each other). However, if the incident / exit optical axis is inclined, the light intensity of the return light fluctuates due to the positional deviation of the light input / output unit or the like in the predetermined axis direction, so the light input / output unit or the like is accurately aligned. There is a problem that it is difficult.

  An object of the present invention is to provide a wavelength selective switch capable of accurately aligning an optical input / output unit and the like and a method for manufacturing the same when the input / output optical axis of each optical input / output port is inclined. To do.

  A wavelength selective switch according to an embodiment of the present invention is a wavelength selective switch including an optical input / output unit, a spectroscopic element, and an optical deflection element that are arranged side by side on a predetermined axis. The optical input / output unit includes a first optical input port and a first optical output port, and performs input / output with an optical axis inclined in a first direction intersecting the predetermined axis with respect to the predetermined axis. Three or more including the first optical input / output port, the second optical input port, and the second optical output port, and performing input / output with an optical axis inclined in a first direction with respect to a predetermined axis. The second light input / output port and a centering port for entering and exiting the light for alignment along the optical axis along a predetermined axis. The incident / exit angle of the first optical input / output port and the incident / exit angle of the second optical input / output port with respect to a predetermined axis are different from each other. The spectroscopic element changes the optical axes of the incoming and outgoing light of the first and second light input / output ports at an angle corresponding to the wavelength in a direction intersecting the predetermined axis and the first direction. The light deflecting element includes a first light deflecting unit that directs light from the first light input port that has passed through the spectroscopic element to the first light output port, and light from the second light input port that has passed through the spectroscopic element. And a second light deflector directed to the two light output ports.

  According to the wavelength selective switch and the method for manufacturing the same according to the present invention, when the input / output optical axes of the respective optical input / output ports are inclined, the optical input / output unit and the like can be accurately aligned.

FIG. 1 is a schematic diagram illustrating a configuration of a wavelength selective switch according to the first embodiment. FIG. 2 is a schematic diagram illustrating a configuration of the wavelength selective switch according to the first embodiment. FIG. 3 is a diagram illustrating a configuration of the light input / output unit viewed from the z-axis direction. FIG. 4 is a side view showing the configuration of the light input / output unit viewed from the y-axis direction. FIG. 5 is a front view of the light deflection element viewed from the z-axis direction. FIG. 6 is a diagram illustrating a state of the alignment work viewed from the y-axis direction of the orthogonal coordinate system. FIG. 7 is a diagram illustrating a typical example of an optical path of light for alignment. FIG. 8 is a front view of the light deflection element viewed from the z-axis direction, and shows a light reflection part for reflecting the alignment light in addition to the first and second light deflection parts. . FIG. 9 is a front view of the light deflecting element viewed from the z-axis direction, and shows a light reflecting portion for reflecting the alignment light in addition to the first and second light deflecting portions. . FIG. 10 is a flowchart showing the alignment process of the wavelength selective switch. FIG. 11 is a side view schematically showing the configuration of the light input / output unit according to the first modification. FIG. 12 is a side view schematically showing the configuration of the light input / output unit according to the second modification. FIG. 13 is a side view schematically showing the configuration of the light input / output unit according to the third modification. FIG. 14 is a side view schematically showing the configuration of the light input / output unit according to the fourth modification. FIG. 15 is a side view schematically showing the configuration of the light input / output unit according to the fifth modification.

  Hereinafter, embodiments of a wavelength selective switch and a manufacturing method thereof according to the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
1 and 2 are schematic diagrams illustrating the configuration of a wavelength selective switch 1A according to the first embodiment. In the following drawings, an orthogonal coordinate system S is shown. FIG. 1 is a side view of the wavelength selective switch 1A as viewed from the y-axis direction of the orthogonal coordinate system S, and shows a schematic configuration of the wavelength selective switch 1A in a plane including the x-axis and the z-axis. FIG. 2 is a top view of the wavelength selective switch 1A viewed from the x-axis direction of the orthogonal coordinate system S, and shows a schematic configuration of the wavelength selective switch 1A in a plane including the y-axis and the z-axis.

  As shown in FIGS. 1 and 2, the wavelength selective switch 1 </ b> A includes an optical input / output unit 10, a spectroscopic element 20, and an optical deflection element 30. The light input / output unit 10, the spectroscopic element 20, and the light deflection element 30 are arranged side by side on a predetermined axis C. The predetermined axis C is an axis extending in the z-axis direction, for example. 1 and 2, the predetermined axis C is drawn in a straight line, but the predetermined axis C may be bent, for example, by arranging a reflecting mirror or the like in the middle.

  FIG. 3 is a diagram illustrating the configuration of the light input / output unit 10 viewed from the direction of the predetermined axis C (z-axis direction). FIG. 4 is a side view showing the configuration of the light input / output unit 10 viewed from the y-axis direction. As shown in FIGS. 3 and 4, the optical input / output unit 10 includes a first portion 10a and a second portion 10b. The first portion 10a and the second portion 10b are arranged side by side in a first direction (in the present embodiment, the x-axis direction) intersecting the predetermined axis C shown in FIGS. Yes.

  The first portion 10 a includes three or more first optical input / output ports 11. In the present embodiment, these optical input / output ports 11 are aligned in the x-axis direction. These optical input / output ports 11 include one or more first optical input ports 11a and one or more first optical output ports 11b. As an example, FIGS. 3 and 4 show one optical input port 11a and a plurality of optical output ports 11b. In this case, the optical input port 11a emits, for example, light L11 that is wavelength multiplexed light into the wavelength selective switch 1A. The light output port 11b receives the wavelength component L12 deflected by the light deflection element 30, for example.

  As shown in FIG. 4, the first portion 10a has an optical axis inclined with respect to a predetermined axis C in a first direction (in this embodiment, the x-axis direction) intersecting the predetermined axis C. Incoming and outgoing of the optical input / output port 11 (that is, emission of the light L11 from the optical input port 11a and incidence of the wavelength component L12 to the optical output port 11b) is performed. The angle range of the incident / exit angle θ1 of the light input / output port 11 with respect to the predetermined axis C is, for example, 0 ° <θ1 <5 °, and more preferably 0 ° when the predetermined axis C is 0 °. <Θ1 <3 °.

  The second portion 10 b includes three or more second optical input / output ports 12. In the present embodiment, these optical input / output ports 12 are aligned in the x-axis direction. These optical input / output ports 12 include one or more second optical input ports 12a and one or more second optical output ports 12b. As an example, FIG. 3 and FIG. 4 show one optical input port 12a and a plurality of optical output ports 12b. In this case, the optical input port 12a emits, for example, light L21, which is wavelength multiplexed light, into the wavelength selective switch 1A. The optical output port 12b receives the wavelength component L22 deflected by the optical deflection element 30, for example.

  As shown in FIG. 4, in the second portion 10b, the light input / output port 12 enters and exits with the optical axis inclined in the x-axis direction (that is, the light L21 emitted from the light input port 12a and the light output). The wavelength component L22 is incident on the port 12b. The incident / exit angle of the light input / output port 12 with respect to the predetermined axis C is different from the incident / exit angle θ1 of the light input / output port 11, for example, −θ1.

  Each light input / output port 11 includes an optical fiber 11c and a condensing element (condensing lens) 11d. Each condensing element 11d is optically coupled to the end face of the corresponding optical fiber 11c. Similarly, each light input / output port 12 includes an optical fiber 12c and a condensing element (condensing lens) 12d. Each condensing element 12d is optically coupled to the end face of the corresponding optical fiber 12c.

  As shown in FIG. 4, the optical axes of the optical fibers 11c and the condensing elements 11d corresponding to the optical fibers 11c are shifted from each other. Specifically, the optical axis of the condensing element 11d is deviated by Δα (> 0) with respect to the optical axis of the optical fiber 11c, and the deviation amount Δα is in three or more optical input / output ports 11. Equal to each other. Thus, a uniform positive incident / exit angle θ1 is given to three or more light input / output ports 11. In the present embodiment, the three or more optical fibers 11c are arranged at regular intervals with an interval α, and the three or more condensing elements 11d corresponding thereto are also equidistant from each other with an interval α. Is arranged.

  On the other hand, the optical axes of the optical fibers 12c and the condensing elements 12d corresponding to the optical fibers 12c are also shifted from each other in the x-axis direction. However, the amount of deviation is different from the amount of deviation of the condensing element 11d, for example, −Δα. Further, the deviation amount −Δα is equal to each other in the three or more optical input / output ports 12. As a result, a uniform negative incident / exit angle −θ1 is given to the three or more light input / output ports 12. In the present embodiment, the three or more optical fibers 12c are arranged at equal intervals with an interval α, and the corresponding three or more condensing elements 12d are also equally spaced with each other at an interval α. Is arranged.

  In this embodiment, the light input / output unit 10 further includes three alignment ports 13 separately from the light input / output ports 11 and 12. The alignment port 13 is a port for entering / exiting the alignment light L3 with an optical axis along a predetermined axis C. These alignment ports 13 also include an optical fiber 13c and a condensing element 13d optically coupled to the end face of the optical fiber 13c. However, the optical axis of the optical fiber 13c and the optical axis of the condensing element 13d coincide with each other. Therefore, the light L3 incident / exited at the alignment port 13 propagates along the predetermined axis C.

  In the present embodiment, the three alignment ports 13 include one alignment port 13a and two alignment ports 13b. The alignment port 13a is provided between the three or more light input / output ports 11 and the three or more light input / output ports 12 (typically, the central portion of the light input / output unit 10 in the x-axis direction). Has been placed. The two alignment ports 13b are respectively arranged on both sides of the alignment port 13a in the x-axis direction, that is, at positions sandwiching the alignment port 13a therebetween. The two alignment ports 13b of the present embodiment are respectively arranged at both ends of the arrangement of the light input / output ports 11 and 12 (that is, both ends of the light input / output unit 10 in the x-axis direction).

  The optical fibers 11c and 12c adjacent to the optical fiber 13c and the optical fiber 13c are arranged with an interval α therebetween. On the other hand, the condensing elements 11d and 12d adjacent to the condensing element 13d and the condensing element 13d are arranged with an interval α + Δα (or α−Δα). With such a configuration, the optical axis deviation amount Δα between the optical fiber 11c and the condensing element 11d and the optical axis deviation amount −Δα between the optical fiber 12c and the condensing element 12d are realized. In other words, in this embodiment, the optical fibers 11c, 12c, and 13c are arranged at equal pitches, and the light collecting elements 11d, 12d, and 13d are arranged at unequal pitches. The position of the condensing element 11d is shifted to one side (the positive side of the x axis) in the arrangement direction with respect to the optical fiber 11c, and the position of the condensing element 12d is in the arrangement direction with respect to the optical fiber 12c. Is shifted to the other side (the negative side of the x-axis).

  Please refer to FIG. 1 and FIG. 2 again. The wavelength selective switch 1A further includes a relay optical system 41 and an anamorphic optical system 42 as a pre-stage optical system disposed on a predetermined axis C between the light input / output unit 10 and the spectroscopic element 20. The relay optical system 41 includes two lenses 41 a and 41 b provided in common for the light input / output ports 11 and 12. The lens 41a is, for example, a convex spherical lens having optical power in the x-axis direction and the y-axis direction. The lens 41a is disposed in front of the lens 41b, and the front focal point of the lens 41a is disposed so as to substantially coincide with the rear focal point of the light collecting elements 11d to 13d (see FIG. 4). That is, the lens 41a is disposed at a position away from the light condensing elements 11d and 12d by the focal length f1 of the light condensing elements 11d to 13d and the focal length f2 of the lens 41a.

  The lens 41a is light that has passed through the lens 41a in the x-axis direction and the y-axis direction as compared with the beam sizes at the beam waist positions of the light L11 and the light L21 that are incident on the lens 41a from the light input / output unit 10. It is preferable to relatively increase the beam size at the beam waist position of L11 and light L21. In this way, for example, when optical control is performed via the relay optical system 41 and the anamorphic optical system 42 in the wavelength selective switch 1A, an increase in loss at the optical input / output ports 11 and 12 of the optical input / output unit 10 is increased. Can be suppressed.

  The lens 41b has optical power at least in the x-axis direction. The lens 41b is, for example, a cylindrical lens having optical power only in the x-axis direction. The front focal point of the lens 41b is disposed so as to substantially coincide with the rear focal point of the lens 41a. The rear focal point of the lens 41b is arranged so as to substantially coincide with the front focal point of a condenser lens 43 described later. In other words, the lens 41b is positioned away from the lens 41a by the focal length f2 of the lens 41a and the focal length f3 of the lens 41b, and by the focal length f3 of the lens 41b and the focal length f4 of the condenser lens 43. It is arranged at a position away from the condenser lens 43. The lenses 41a and 41b are not limited to the light transmission type as shown in FIGS. 1 and 2, but may be a reflection type such as a mirror.

  The anamorphic optical system 42 is provided in common with respect to the light input / output ports 11 and 12, and is disposed in front of or behind the relay optical system 41. FIGS. 1 and 2 show a configuration in which an anamorphic optical system 42 is disposed after the relay optical system 41. The anamorphic optical system 42 receives the lights L11 and L21 emitted from the lens 41b of the relay optical system 41, and expands the beam sizes of the lights L11 and L21 in the y-axis direction. The anamorphic optical system 42 has a function of converting and outputting the aspect ratio of the input beam, and can be configured by a prism pair, a cylindrical lens, a cylindrical mirror, or the like alone or in combination. In the present embodiment, for example, a pair of prisms 42a and 42b is illustrated.

  The spectroscopic element 20 is provided in common to the light input / output ports 11 and 12, and the optical axis of the incident / exit light of the light input / output ports 11 and 12 intersects the predetermined axis C and the x-axis direction, For example, it is changed at an angle corresponding to the wavelength in the y-axis direction. When the light L11, L21 from the light input ports 11a, 12a is wavelength multiplexed light, the spectroscopic element 20 splits the light L11, L21 into a plurality of wavelength components. In FIG. 1 and FIG. 2, only certain wavelength components L12 and L22 out of a plurality of wavelength components are shown as representatives for easy understanding. As the spectroscopic element 20, for example, a diffraction grating can be used.

  On a predetermined axis C between the spectroscopic element 20 and the light deflection element 30, a condensing lens (condensing element) 43 is disposed. The condensing lens 43 receives the wavelength components L12 and L22 that are split and emitted by the spectroscopic element 20, and deflects the wavelength components L12 and L22 toward the light deflection element 30 while collimating in the x-axis direction, for example. At the same time, the light is condensed on the light deflection element 30 in the y-axis direction. As the condenser lens 43, for example, a rotationally symmetric lens such as a convex spherical lens having optical power in the x-axis direction and the y-axis direction is used.

  The light deflection element 30 is disposed at the rear focal point of the condenser lens 43. The light deflection element 30 receives the wavelength component L12 collected by the condenser lens 43 from the light input port 11a through the spectroscopic element 20, and deflects the wavelength component L12 toward a predetermined light output port 11b according to the wavelength. To do. Similarly, the light deflection element 30 receives the wavelength component L21 collected by the condenser lens 43 from the light input port 12a through the spectroscopic element 20, and toward the predetermined light output port 12b corresponding to the wavelength. L22 is deflected. For this purpose, the light deflection element 30 has a plurality of light deflection regions arranged two-dimensionally in a plane intersecting with a predetermined axis C. The light deflection element 30 receives the corresponding wavelength components L21 and L22 in each light deflection region and independently deflects the wavelength components L12 and L22 toward the light output ports 11b and 12b.

  FIG. 5 is a front view of the light deflection element 30 viewed from the direction of the predetermined axis C. FIG. As shown in FIG. 5, the light deflection element 30 includes a first light deflection unit 31 and a second light deflection unit 32 arranged in the x-axis direction. The first light deflection unit 31 includes a plurality of light deflection regions 31 a arranged in the y-axis direction (spectral direction), and each wavelength component from the light input port 11 a that has passed through the spectroscopic element 20 corresponds to the light deflection region 31 a. And directs these wavelength components to the optical output port 11b. The second light deflecting unit 32 includes a plurality of light deflecting regions 32a arranged in the y-axis direction (spectral direction), and each wavelength component from the light input port 12a that has passed through the spectroscopic element 20 corresponds to the light deflection. Receiving in the region 32a, these wavelength components are directed to the optical output port 12b.

  As the optical deflection element 30, for example, a phase modulation element such as LCOS (Liquid Crystal On Silicon) is preferably used. Such a phase modulation element has a plurality of pixels that perform phase modulation, and deflects the optical path of incident light by presenting a diffraction grating-like phase modulation pattern. In addition to the phase modulation element, various elements such as a MEMS (Micro Electro Mechanical Systems) element can be used as the light deflection element 30.

  When an LCOS type phase modulation element is used as the optical deflection element 30, the wavelength components L12, L22 reaching from the optical input ports 11a, 12a in a plane including the predetermined axis C and the x-axis direction (that is, in the xz plane). The optical axis may be orthogonal to the modulation surface of the phase modulation element. As a result, more precise deflection control is possible. In such a configuration, for example, the input / output angles θ1, − of the light input / output ports 11 and 12 with respect to a predetermined axis C are set so that the optical axes of the wavelength components L12 and L22 are orthogonal to the modulation surface in the xz plane. It can be suitably realized by setting θ1. In this case, the upstream optical system (relay optical system 41 and anamorphic optical system 42) and the condensing lens 43 are arranged so that the optical axes of the wavelength components L12 and L22 are orthogonal to the modulation plane in the xz plane. The optical path of light from the input / output ports 11 and 12 may be changed. In this case, it is further preferable that the central optical axes of the upstream optical system (relay optical system 41 and anamorphic optical system 42) and the condensing lens 43 in the x-axis direction coincide with each other. In this case, the optical axes of the incoming / outgoing lights L11 and L12 of the optical input / output port 11 and the optical axes of the incoming and outgoing lights L21 and L22 of the optical input / output port 12 are symmetric with respect to a predetermined axis C. Good. The predetermined axis C is an in-plane (in the xz plane) including the predetermined axis C and the x-axis direction when the light emitted along the predetermined axis C reaches the modulation surface of the phase modulation element. ) In which the optical axis of the light is orthogonal to the modulation surface of the phase modulation element.

  The wavelength components L12 and L22 deflected by the light deflection element 30 reach predetermined light output ports 11b and 12b via the condenser lens 43, the spectroscopic element 20, the anamorphic optical system 42, and the relay optical system 41. Are output to the outside of the wavelength selective switch 1A.

  An alignment process (alignment) will be described as a process for manufacturing the wavelength selective switch 1A having the above configuration. FIG. 6 is a diagram illustrating a state of the alignment work viewed from the y-axis direction of the orthogonal coordinate system S. FIG. 10 is a flowchart showing the alignment process of the wavelength selective switch 1A.

  In the alignment step of the present embodiment, as shown in FIG. 6, first, the planar reflecting mirror 50 is disposed on the predetermined axis C in front of the light input / output unit 10. At this time, the light reflecting surface 50a of the planar reflecting mirror 50 is set to be perpendicular to the predetermined axis C. Next, the alignment light L3 is input to the three alignment ports 13 (first step S1). As described above, since the incident / exit optical axis of the alignment port 13 is along the predetermined axis C, the alignment light L3 travels along the predetermined axis C (typically in parallel). The light reaches the light reflecting surface 50a of the plane reflecting mirror 50. The alignment light L3 is reflected with both the incident angle and the emission angle at the light reflecting surface 50a being 0 °, and returns to the alignment port 13 along the original optical path.

  Here, FIG. 7 is a diagram illustrating a typical example of the optical path of the alignment light L3. As shown in FIG. 7, the optical path of the alignment light L3 of the present embodiment is between the light input / output unit 10 and the preceding optical system (relay optical system 41), and between the relay optical system 41 and the condenser lens. It extends along the predetermined axis C (becomes parallel) with the terminal 43. Accordingly, the planar reflecting mirror 50 is disposed between the light input / output unit 10 and the preceding optical system (relay optical system 41) (position A1 in the drawing) or between the relay optical system 41 and the condenser lens 43 (for example, FIG. By arranging at the center position A2), the alignment light L3 can be suitably returned to the alignment port 13. Alternatively, the planar reflecting mirror 50 may be disposed between the lens 41a and the lens 41b of the relay optical system 41 on the intersection P1 where the plurality of lights L3 respectively emitted from the plurality of alignment ports 13 intersect with each other. (Position A3 in the figure). In this case, the light L3 emitted from the alignment port 13 positioned at one end of the light input / output unit 10 in the x-axis direction is the alignment port 13 positioned at the other end of the light input / output unit 10 in the x-axis direction. Return to.

  Further, instead of the plane reflecting mirror 50, the light deflection element 30 may be used. That is, the light deflecting element 30 may be provided with a light reflecting portion separately from the first light deflecting portion 31 and the second light deflecting portion 32, and the alignment light L3 may be reflected by the light reflecting portion. At this time, unlike the light deflection units 31 and 32, the light reflection unit does not deflect the alignment light L3 but reflects the light L3 with both the incident angle and the emission angle set to 0 °. At this time, as shown in FIG. 7, the plurality of lights L <b> 3 respectively emitted from the plurality of alignment ports 13 reach one point P <b> 2 on the deflection surface of the light deflection element 30. Accordingly, the light L3 emitted from the alignment port 13 positioned at one end of the light input / output unit 10 returns to the alignment port 13 positioned at the other end of the light input / output unit 10.

  FIGS. 8 and 9 are front views of the light deflection element 30 as viewed from the z-axis direction, in order to reflect the alignment light L3 in addition to the first and second light deflection units 31 and 32. FIG. The light reflecting portions 33 and 34 are respectively shown. The light reflecting portion 33 shown in FIG. 8 is a light reflecting portion that is applied when light L3 having a certain fixed wavelength width (for example, the bandwidths of the light L11 and L21 that are wavelength multiplexed light) is incident. And having a shape extending in the spectral direction (y-axis direction). Further, light L3 having a plurality of discrete wavelength components (for example, both wavelength components and center wavelength components of light L11 and L21 that are wavelength multiplexed light) is incident on the plurality of light reflecting portions 34 shown in FIG. It is a light reflection part applied to the case, and is arranged side by side in the spectral direction (y-axis direction). As shown in FIGS. 8 and 9, the light reflecting portions 33 and 34 are disposed between the first light deflecting portion 31 and the second light deflecting portion 32 in the x-axis direction. Since the incident angle of the light L3 to the diffraction grating 20 is different from the incident angles of the lights L11 and L21 to the diffraction grating 20, the positions of the light reflecting portions 33 and 34 are the first and second light deflecting portions. 31 and 32 are slightly shifted in the y-axis direction. In other words, the positions of the first and second light deflection units 31 and 32 are slightly shifted in the y-axis direction with respect to the light reflection units 33 and 34.

  Next, the alignment light L3 reflected by the planar reflecting mirror 50 or the light deflection element 30 is acquired via the alignment port 13, and the intensity of the alignment light L3 is detected (second step S2). ). At this time, the detection intensity of the light L3 is smaller as the optical axis of the light L3 is farther from the alignment port 13. This means, for example, that the lens array composed of the light condensing elements 11d to 13d is displaced from a predetermined position with respect to the fiber array composed of the optical fibers 11c to 13c.

  In the subsequent third step S3, in the direction in which the intensity of the alignment light L3 obtained in the second step S2 increases, that is, in the direction in which the optical axis of the light L3 approaches the alignment port 13, the light input / output unit 10 Adjust the incoming and outgoing angles. In one embodiment, first, the intensity of the light L3 detected from the alignment port 13a disposed between the optical input / output port 11 and the optical input / output port 12 is maximized (that is, the optical loss is reduced). The relative position of the condensing elements 11d to 13d and the optical fibers 11c to 13c is adjusted so as to be minimized. Next, the condensing elements 11d to 13d and the optical fibers 11c to 11c are arranged so that the intensities of the light L3 detected from the two alignment ports 13b located at both ends of the array of the light input / output ports 11 and 12 approach uniformly. The relative position with respect to 13c is adjusted. Ideally, the light loss of the light L3 detected at the three alignment ports 13 is preferably minimized.

  In the wavelength selective switch 1A of the present embodiment having the above-described configuration, the light input / output unit 10 is not aligned with the light input / output ports 11 and 12, but the light L3 for alignment with an optical axis along a predetermined axis C. Further includes an alignment port 13 for entering and exiting. Since the input / output light of the light input / output ports 11 and 12 is inclined with respect to the predetermined axis C, it is difficult to use for alignment, but by preparing such an alignment port 13 separately, alignment is possible. Work can be done easily.

  Further, as in the present embodiment, the optical input / output ports 11 and 12 and the alignment port 13 may include optical fibers 11c to 13c, respectively. In this case, the optical axis direction of the optical fibers 11c and 12c is different from the incident / exit direction of the optical input / output ports 11 and 12, and the optical axis direction of the optical fiber 13c and the incident / exit direction of the alignment port 13 are mutually different. It is good to agree. Thereby, the optical axis directions of the optical fibers 11c to 13c can be aligned in a direction along the predetermined axis C, for example, and the wavelength selective switch 1A can be easily manufactured.

  When the optical axes of the optical fibers 11c to 13c are along the predetermined axis C, the light input / output ports 11 and 12 include condensing elements 11d and 12d that are optically coupled to the end faces of the optical fibers 11c and 12c. The optical axes of the optical fibers 11c and 12c and the optical axes of the condensing elements 11d and 12d are preferably shifted from each other. Further, the alignment port 13 preferably includes a condensing element 13d optically coupled to the end face of the optical fiber 13c, and the optical axis of the optical fiber 13c and the optical axis of the condensing element 13d are preferably coincident with each other. Thereby, the incident / exit angle of the light input / output ports 11 and 12 inclined with respect to the predetermined axis C and the incident / exit angle of the alignment port 13 along the predetermined axis C can be easily realized. . Also, with such a configuration, the optical input / output ports 11 and 12 can ensure a sufficient effective diameter. Therefore, even when the wavelength selective switch 1A is downsized, the absolute values of the incident and outgoing angles θ1 and −θ1 can be set. It can be made sufficiently large.

  When the optical input / output port 11 and the optical input / output port 12 are arranged side by side in a certain direction as in the present embodiment, the alignment port 13 is an arrangement of the optical input / output ports 11 and 12. And both the optical input / output port 11 and the optical input / output port 12. Thereby, the alignment operation | work of the optical input / output part 10 can be performed with sufficient balance, and alignment accuracy can be improved more. In addition, even if the alignment port 13 is provided with only the alignment port 13a or only the alignment port 13b is provided, the effects of the present embodiment can be suitably achieved. .

  In the wavelength selective switch 1A of the present embodiment, the preceding optical system (relay optical system 41 and anamorphic optical system 42) is disposed between the light input / output unit 10 and the spectroscopic element 20 on a predetermined axis C. ing. In this case, as described above, the planar reflecting mirror 50 may be disposed between the light input / output unit 10 and the preceding optical system. Thereby, alignment of the condensing elements 11d to 13d with respect to the optical fibers 11c to 13c of the light input / output unit 10 can be accurately performed without being affected by position errors of other optical components. Alternatively, as described above, the plane reflecting mirror 50 has the intersection P1 where the plurality of lights L3 intersect between the relay optical system 41 and the condenser lens 43 or between the lens 41a and the lens 41b of the relay optical system 41. Alternatively, the light deflection element 30 may be used in place of the planar reflecting mirror 50. With any one of these, the condensing elements 11d to 13d can be aligned so as to absorb position errors of optical components other than the condensing elements 11d to 13d.

(First modification)
FIG. 11 is a side view schematically showing the configuration of the light input / output unit 10A according to a modification of the first embodiment, and shows a form in which the light input / output unit 10A is viewed from the y-axis direction. . In the optical input / output unit 10A according to this modification, unlike the above embodiment (see FIG. 4), the optical axis of the condensing element 11d is shifted by −Δα with respect to the optical axis of the optical fiber 11c. Note that this deviation amount −Δα is equal to each other in the three or more optical input / output ports 11. Thus, a uniform negative incident / exit angle −θ1 is given to the three or more light input / output ports 11.

  On the other hand, the optical axis of the condensing element 12d is shifted by Δα in the positive direction with respect to the optical axis of the optical fiber 12c. Note that the shift amount Δα is equal in the three or more optical input / output ports 12. Thus, a uniform positive incident / exit angle θ1 is given to the three or more light input / output ports 12.

  Thus, in this modification, the optical fibers 11c, 12c, and 13c are arranged at equal pitches, and the light collecting elements 11d, 12d, and 13d are arranged at unequal pitches. The position of the condensing element 11d is shifted to one side (the negative side of the x axis) in the arrangement direction with respect to the optical fiber 11c, and the position of the condensing element 12d is in the arrangement direction with respect to the optical fiber 12c. Is shifted to the other side (the positive side of the x-axis). Accordingly, the light input / output angle is negative (−θ1) at the light input / output port 11, and the light input / output angle is positive (θ1) at the light input / output port 12 positioned on the negative side of the x-axis with respect to the light input / output port 11. Therefore, the incoming / outgoing light of the light input / output port 11 and the incoming / outgoing light of the light input / output port 12 cross each other. Even in such a form, the alignment work can be easily performed using the alignment port 13 as in the first embodiment.

(Second modification)
FIG. 12 is a side view schematically showing a configuration of an optical input / output unit 10B according to another modification of the first embodiment, and shows a configuration in which the optical input / output unit 10B is viewed from the y-axis direction. Yes. In the light input / output unit 10B according to the present modification, unlike the first modification (see FIG. 11), the optical axis of the optical fiber 11c is Δα in the positive direction with respect to the optical axis of the condensing element 11d. It is only shifted. Note that the shift amount Δα is equal among the three or more optical input / output ports 11. Thus, a uniform negative incident / exit angle −θ1 is given to the three or more light input / output ports 11.

  On the other hand, the optical axis of the optical fiber 12c is shifted by −Δα with respect to the optical axis of the condensing element 12d. Note that the shift amount Δα is equal in the three or more optical input / output ports 12. Thus, a uniform positive incident / exit angle θ1 is given to the three or more light input / output ports 12.

  Thus, in this modification, the condensing elements 11d, 12d, and 13d are arranged at equal pitches, and the optical fibers 11c, 12c, and 13c are arranged at unequal pitches. The position of the optical fiber 11c is shifted to one side (the positive side of the x-axis) in the arrangement direction with respect to the condensing element 11d, and the position of the optical fiber 12c is in the arrangement direction with respect to the condensing element 12d. Is shifted to the other side (the negative side of the x-axis). Accordingly, the light input / output angle is negative (−θ1) at the light input / output port 11, and the light input / output angle is positive (θ1) at the light input / output port 12 positioned on the negative side of the x-axis with respect to the light input / output port 11. Therefore, the incoming / outgoing light of the light input / output port 11 and the incoming / outgoing light of the light input / output port 12 cross each other. Even in such a configuration, the alignment work can be easily performed using the alignment port 13 as in the first modification.

  In the first embodiment, similarly, the light collecting elements 11d, 12d, and 13d may be arranged at an equal pitch, and the optical fibers 11c, 12c, and 13c may be arranged at an unequal pitch. In this case, the position of the optical fiber 11c may be shifted to the negative side of the x axis with respect to the condensing element 11d, and the position of the optical fiber 12c may be shifted to the positive side of the x axis with respect to the condensing element 12d. . As a result, the light input / output angle is positive (θ1) at the light input / output port 11 and the light input / output angle is negative (−θ1) at the light input / output port 12 positioned on the negative side of the x-axis with respect to the light input / output port 11. It becomes.

(Third Modification)
FIG. 13 is a side view schematically showing a configuration of an optical input / output unit 10C according to still another modification of the first embodiment, and shows a form of the optical input / output unit 10C viewed from the y-axis direction. ing. In the optical input / output unit 10C according to this modification, unlike the above-described embodiment (see FIG. 4), a plurality of port groups 14 including the optical input / output ports 11 and 12 are arranged side by side in the x-axis direction. Yes. The optical input / output ports 11 and 12 are alternately arranged in the x-axis direction.

  Specifically, each port group 14 has a multi-core optical fiber 15. The multi-core optical fiber 15 includes at least two cores (optical waveguides) 15a and 15b arranged in the x-axis direction. One core 15 a constitutes the optical input / output port 11, and the other core 15 b constitutes the optical input / output port 12. Each port group 14 has one condensing element 14d. The condensing element 14d is optically coupled to the end faces of the two cores 15a and 15b. The optical axis of the core 15a is shifted in the positive x-axis direction with respect to the optical axis of the light condensing element 14d, so that a negative input / output angle −θ1 is given to the light input / output port 11. Further, the optical axis of the core 15b is shifted in the negative x-axis direction with respect to the optical axis of the light condensing element 14d, whereby a positive incident / exit angle θ1 is given to the light input / output port 12.

  Thus, in this modification, the position of the light condensing element 14d is shifted to one side (the positive side of the x axis) in the arrangement direction with respect to the core 15a, and the other position in the arrangement direction with respect to the core 15b. Is shifted to the side (the negative side of the x-axis). Accordingly, the light input / output angle at the light input / output port 11 is negative (−θ1), and the light input / output angle at the light input / output port 12 is positive (θ1). Since the light input / output ports 11 and 12 are alternately arranged in this modification, the light input / output light of the light input / output port 11 and the light input / output light of the light input / output port 12 intersect each other. .

  The alignment port 13a is arranged between the plurality of port groups 14 (preferably near the center of the plurality of port groups 14). The alignment ports 13b are arranged at both ends of the array of the plurality of port groups 14, respectively. The optical fiber 13c constituting these alignment ports 13 is a single core optical fiber, and has a single core 13e. The optical axis of the core 13e coincides with the optical axis of the condensing element 13d, whereby the alignment port 13 enters and outputs the light L3 with the optical axis along the predetermined axis C. .

  Even if it is the above forms, the alignment operation | work can be easily performed using the alignment port 13 similarly to the said 1st Embodiment.

(Fourth modification)
FIG. 14 is a side view schematically showing a configuration of an optical input / output unit 10D according to still another modified example of the first embodiment, and shows a configuration in which the optical input / output unit 10D is viewed from the y-axis direction. ing. In the optical input / output unit 10D according to this modification, a plurality of port groups 16 including the optical input / output ports 11 and 12 and the alignment port 13 are arranged side by side in the x-axis direction. The optical input / output ports 11 and 12 are alternately arranged in the x-axis direction, and the alignment port 13 is disposed between the optical input / output port 11 and the optical input / output port 12.

  Specifically, each port group 16 has a multi-core optical fiber 17. The multi-core optical fiber 17 includes at least three cores (optical waveguides) 17a to 17c arranged in the x-axis direction. The core 17a constitutes the optical input / output port 11, the core 15b constitutes the optical input / output port 12, and the core 17c constitutes the alignment port 13. Each port group 16 has one light collecting element 16d. The condensing element 16d is optically coupled to the end faces of the three cores 17a to 17c. The optical axis of the core 17a is deviated in the positive x-axis direction with respect to the optical axis of the condensing element 16d, whereby a negative incident / exit angle −θ1 is given to the light input / output port 11. The optical axis of the core 17b is shifted in the negative x-axis direction with respect to the optical axis of the condensing element 16d, so that a positive incident / exit angle θ1 is given to the light input / output port 12. The optical axis of the core 17c coincides with the optical axis of the condensing element 16d, whereby the alignment port 13 enters and outputs the light L3 with the optical axis along the predetermined axis C.

  Even if it is the above forms, the alignment operation | work can be easily performed using the alignment port 13 similarly to the said 1st Embodiment.

(Fifth modification)
FIG. 15 is a side view schematically showing a configuration of an optical input / output unit 10E according to still another modification of the first embodiment, and shows a form of the optical input / output unit 10E viewed from the y-axis direction. ing. In the optical input / output unit 10E according to this modification, a plurality of port groups 14 according to the third modification are arranged side by side in the x-axis direction. The optical input / output ports 11 and 12 are alternately arranged in the x-axis direction.

  However, in the present modification, unlike the third modification, the alignment port 13 is not arranged independently of the plurality of port groups 14. In other words, in this modification, the optical input / output port 11 also serves as an alignment port in each port group 14, and the optical input / output port 11 has the light L11, L12 and the optical axis along a predetermined axis C. Incident light L3 is incident / exited. Such a configuration is suitably realized by inclining the optical axis of the multi-core optical fiber 15 constituting each port group 14 with respect to a predetermined axis C by, for example, an angle θ1. At this time, the angle of the incoming / outgoing light L21, L22 at the light input / output port 12 with respect to the predetermined axis C is 2θ.

  Even with the above configuration, the alignment work can be easily performed using the light input / output port 11 (alignment port).

  The wavelength selective switch and the manufacturing method thereof according to each of the embodiments and modifications described above can be variously modified. For example, in each of the above embodiments and modifications, the light input / output port and the alignment port have been described as including an optical fiber and a condensing lens. However, the light input / output port and the alignment port have such a configuration. Not limited to.

  In the above embodiment and the first to third modifications, the case where the light input / output unit has three alignment ports is illustrated, but the light input / output unit includes at least one alignment port. It only has to have. Further, regarding the arrangement of the alignment port, various arrangements are possible in addition to the above-described embodiment and the first to third modifications.

  Moreover, although the multi-core optical fiber is used in the said 3rd-5th modification, you may comprise the part corresponded to the several core of a multi-core optical fiber by several single core optical fiber. Even if it is such a form, the effect similar to the 3rd-5th modification can be acquired.

  DESCRIPTION OF SYMBOLS 1A ... Wavelength selection switch, 10, 10A-10E ... Optical input / output part, 11, 12 ... Optical input / output port, 11a, 12a ... Optical input port, 11b, 12b ... Optical output port, 11c, 12c, 13c ... Optical fiber 11d, 12d, 13d ... Condensing element, 13 ... Alignment port, 14, 16 ... Port group, 14d, 16d ... Condensing element, 15, 17 ... Multi-core optical fiber, 15a, 15b, 17a-17c ... Core , 20 ... spectral element, 30 ... light deflecting element, 31, 32 ... light deflecting unit, 50 ... planar reflecting mirror, C ... predetermined axis, L3 ... light for alignment.

Claims (9)

A wavelength selective switch comprising a light input / output unit, a spectroscopic element, and a light deflection element arranged side by side on a predetermined axis,
The optical input / output unit is
Three or more first input / output units including a first optical input port and a first optical output port and performing input / output with an optical axis inclined in a first direction intersecting the predetermined axis with respect to the predetermined axis Optical input / output ports
Three or more second optical input / output ports that include a second optical input port and a second optical output port, and perform input / output with an optical axis inclined in the first direction with respect to the predetermined axis; ,
A centering port for entering and exiting light for alignment with an optical axis along the predetermined axis, and an incident / exit angle of the first light input / output port with respect to the predetermined axis; The incident / exit angles of the second light input / output ports are different from each other,
The spectroscopic element changes the optical axes of incident and outgoing light of the first and second light input / output ports at an angle corresponding to a wavelength in a direction intersecting the predetermined axis and the first direction,
The light deflection element is
A first light deflector for directing light from the first light input port that has passed through the spectroscopic element to the first light output port;
A wavelength selective switch, comprising: a second light deflector that directs light from the second light input port that has passed through the spectroscopic element to the second light output port. The first and second light input / output ports and the alignment port each include an optical fiber,
The optical axis direction of the optical fiber of the first and second optical input / output ports and the incident / exit direction of the first and second optical input / output ports are different from each other,
The wavelength selective switch according to claim 1, wherein an optical axis direction of the optical fiber of the alignment port and an incident / exit direction of the alignment port coincide with each other. The optical axes of the optical fibers of the first and second light input / output ports and the alignment port are along the predetermined axis;
The first and second light input / output ports further include a condensing element optically coupled to the end face of the optical fiber, and the optical axis of the optical fiber and the optical axis of the condensing element are mutually connected. It ’s out of place,
The centering port further includes a condensing element optically coupled to an end face of the optical fiber, and the optical axis of the optical fiber and the optical axis of the condensing element coincide with each other. Item 3. The wavelength selective switch according to Item 2. The amount of deviation between the optical axis of the optical fiber and the optical axis of the condensing element in the three or more first light input / output ports is equal to each other,
The amount of deviation between the optical axis of the optical fiber and the optical axis of the condensing element in the three or more second light input / output ports is equal to each other,
The wavelength selective switch according to claim 3, wherein the shift amount in the first optical input / output port and the shift amount in the second optical input / output port are different from each other. The first optical input / output port and the second optical input / output port are arranged side by side in the first direction;
The alignment port is at least one of both ends of the arrangement of the first and second light input / output ports and between the first light input / output port and the second light input / output port. The wavelength selective switch according to claim 1, wherein the wavelength selective switch is arranged. A plurality of port groups each including the first and second optical input / output ports are arranged side by side in the first direction;
Each port group includes two or more optical waveguides that respectively constitute the first and second optical input / output ports, and a condensing element that is optically coupled to end faces of the two or more optical waveguides, The optical axes of the two or more optical waveguides and the optical axis of the light collecting element are shifted from each other;
2. The wavelength according to claim 1, wherein each port group further includes an optical waveguide constituting the alignment port, and an optical axis of the optical waveguide and an optical axis of the condensing element coincide with each other. Select switch. A method for manufacturing the wavelength selective switch according to any one of claims 1 to 6,
A first step of inputting alignment light to the alignment port;
The alignment light reflected by the reflecting mirror arranged on the predetermined axis or the light deflection element is acquired via the alignment port, and the intensity of the alignment light is detected. Two steps,
A third step of adjusting an incident / exit angle of the light input / output unit with reference to the predetermined axis in a direction in which the intensity of the alignment light obtained in the second step increases. A method for manufacturing a switch. The wavelength selective switch further includes a front optical system disposed between the light input / output unit and the spectroscopic element on the predetermined axis;
The said reflecting mirror is arrange | positioned between the said light input / output part and the said front stage optical system, The said light for alignment reflected in the said reflecting mirror is acquired through the said port for alignment. Manufacturing method of the wavelength selective switch. The light input / output unit has a plurality of alignment ports,
9. The incident / exit angle of the light input / output unit is adjusted so that the intensity of the alignment light approaches uniformly in two or more alignment ports during the third step. A manufacturing method of the wavelength selective switch as described.

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