Wavelength selection switch, optical switching node and communication system

Abstract

The embodiment of the invention provides a wavelength selection switch, an optical switching node and a communication system, which can reduce the number of devices included in the wavelength selection switch and improve the integration level of the wavelength selection switch. The wavelength selective switch comprises an input optical fiber, a lens group, a dispersion unit, an optical switching engine and an output optical fiber array, wherein the dispersion unit comprises an optical metasurface structure; the input optical fiber is used for transmitting input light beams to the lens group; the lens group is used for collimating an input light beam to obtain a first light beam and transmitting the first light beam to the dispersion unit; the optical metasurface structure is used for decomposing the first light beam to obtain multiple paths of second light beams, and the optical metasurface structure is further used for collimating the multiple paths of second light beams to transmit the collimated multiple paths of second light beams to the optical switching engine; the optical switching engine is used for deflecting the transmission direction of each second light beam in the multiple paths of second light beams so as to obtain multiple paths of output light beams, and the multiple paths of output light beams are used for being output through the output optical fiber array.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of optical communication technology, and in particular to a wavelength selective switch, an optical switching node, and a communication system. Background Art

[0002] When an optical network uses technologies such as wavelength division multiplexing (WDM) to transmit light beams, the transmission direction of the light beams can be scheduled through optical switching nodes. Optical switching nodes mainly schedule the transmission direction at the wavelength level through wavelength selective switching (WSS). WSS realizes the deflection of the light beam transmission direction based on the optical switching engine.

[0003] WSS includes a fiber array, a dispersion direction lens, a port direction lens, a grism, and an optical switching engine. The fiber array is used to input a light beam, and the grism disperses the light beam to obtain multiple sub-beams. The dispersion direction lens and the port direction lens are used to collimate the sub-beams along the dispersion direction and the port direction, respectively. The optical switching engine deflects the transmission direction of the collimated sub-beams, and the deflected sub-beams are used to be output from the WSS via the fiber array.

[0004] However, the existing WSS includes a large number of components, which increases the difficulty of assembling the WSS, resulting in low assembly efficiency and poor integration of the WSS. Summary of the invention

[0005] The embodiments of the present application provide a wavelength selective switch, an optical switching node, and a communication system, which can reduce the number of components included in the wavelength selective switch and improve the integration of the wavelength selective switch.

[0006] In a first aspect, an embodiment of the present application provides a wavelength selective switch, comprising: an input optical fiber, a lens group, a dispersion unit, an optical switching engine, and an output optical fiber array, wherein the dispersion unit comprises an optical metasurface structure, the optical metasurface structure comprises a plurality of nanostructures arranged along a first plane, the first plane comprises a dispersion direction and a port direction, then the optical metasurface structure comprises a plurality of nanostructures arranged along the dispersion direction and along the port direction, respectively. First, the input optical fiber is used to transmit an input light beam to the lens group, the transmission direction of the input light beam intersects with the first plane, specifically, the transmission direction of the input light beam is perpendicular to the first plane. Then, the lens group is used to collimate the input light beam to obtain a first light beam, and transmit the first light beam to the dispersion unit. Then, the optical metasurface structure is used to decompose the first light beam along the dispersion direction to obtain multiple second light beams, and the optical metasurface structure is also used to collimate the multiple second light beams along the port direction to transmit the collimated multiple second light beams to the optical switching engine. Then, the optical switching engine is used to deflect the transmission direction of each of the multiple second light beams to obtain multiple output light beams, and the multiple output light beams are used to be output through the output optical fiber array.

[0007] By adopting the optical metasurface structure composed of multiple nanostructures shown in this aspect, the first light beam can be split and each second light beam can be collimated along the port direction while reducing the distortion of the first light beam. The dispersion unit is a device that has the functions of splitting along the dispersion direction and collimating along the port direction, so that the wavelength selective switch does not need to be provided with a lens group with curvature along the port direction, which reduces the number of devices included in the wavelength selective switch, reduces the difficulty of assembling the wavelength selective switch, and improves the assembly efficiency of the wavelength selective switch and the integration of the wavelength selective switch.

[0008] Based on the first aspect, in an optional implementation, the light paths of the multiple second light beams emitted from the dispersion unit have different projection directions in the second plane; the light paths of the multiple second light beams emitted from the dispersion unit have different projection directions in a third plane, and the third plane intersects with the first plane and the second plane respectively.

[0009] By adopting this implementation method, the dispersion unit with an optical metasurface structure can decompose the first light beam along the dispersion direction to obtain multiple second light beams. Compared with the existing grating structure only used for dispersion, the dispersion unit with an optical metasurface structure can reduce the insertion loss in the process of decomposing the first light beam and improve the diffraction efficiency.

[0010] Based on the first aspect, in an optional implementation, the lens group is used to collimate the input light beam along a dispersion direction, the dispersion unit is used to collimate the second light beam along a port direction, and the dispersion direction intersects with the third plane, and the port direction intersects with the second plane.

[0011] As shown in the present implementation, the collimation effect of the lens group along the dispersion direction and the collimation effect of the dispersion unit along the port direction ensure that each second light beam can be transmitted to the optical switching engine at a suitable angle and spot size, thereby ensuring the successful deflection of the transmission direction of each second light beam by the optical switching engine.

[0012] Based on the first aspect, in an optional implementation, the multi-path second light beam includes a first target light beam and a second target light beam, the first target light beam forms a first light spot on the optical switching engine, the second target light beam forms a second light spot on the optical switching engine, in the second plane, the positions of the first light spot and the second light spot are separated from each other, and in the third plane, the positions of the first light spot and the second light spot at least partially overlap.

[0013] By adopting this implementation method, the dispersion unit with an optical metasurface structure can accurately transmit the first target light beam to the optical switching engine to form a first light spot, and accurately transmit the second target light beam to the optical switching engine to form a second light spot. The optical switching engine can accurately deflect the transmission direction of the first target light beam and the transmission direction of the second target light beam.

[0014] Based on the first aspect, in an optional implementation, the optical metasurface structure includes a plurality of units, each of the plurality of units includes at least one nanostructure, the plurality of units include a first unit and a second unit, and the nanostructure included in the first unit is different from the nanostructure included in the second unit.

[0015] By adopting this implementation, the dispersion unit with an optical metasurface structure can decompose the first light beam along the dispersion direction to obtain multiple second light beams. Moreover, the dispersion unit with an optical metasurface structure can also collimate each second light beam along the port direction, so that the wavelength selective switch does not need to be configured with a lens group with curvature along the port direction, thereby reducing the number of devices included in the wavelength selective switch.

[0016] Based on the first aspect, in an optional implementation manner, the nanostructure included in the first unit is different from the nanostructure included in the second unit, which refers to at least one of the following:

[0017] The number of nanostructures included in the first unit is different from the number of nanostructures included in the second unit, the size of the nanostructures included in the first unit is different from the size of the nanostructures included in the second unit, the arrangement of the nanostructures included in the first unit is different from the arrangement of the nanostructures included in the second unit, and the shape of the nanostructures included in the first unit is different from the shape of the nanostructures included in the second unit.

[0018] By adopting this implementation, the dispersion unit with an optical metasurface structure can decompose the first light beam along the dispersion direction to obtain multiple second light beams. Moreover, the dispersion unit with an optical metasurface structure can also collimate each second light beam along the port direction, so that the wavelength selective switch does not need to be configured with a lens group with curvature along the port direction, thereby reducing the number of devices included in the wavelength selective switch.

[0019] Based on the first aspect, in an optional implementation, the optical metasurface structure includes multiple regions, each of the multiple regions includes multiple units, the multiple regions include a first region and a second region, the nanostructure included in the first region is different from the nanostructure included in the second region; the first region is used to receive a first output beam from the optical switching engine, and the second region is used to receive a second output beam from the optical switching engine, and the multi-path output beam includes the first output beam and the second output beam; the first region is also used to focus the first output beam along the port direction, and the focused first output beam is used to output via a first output optical fiber, the second region is also used to focus the second output beam along the port direction, and the focused second output beam is used to output via a second output optical fiber, and the output optical fiber array includes the first output optical fiber and the second output optical fiber.

[0020] By adopting this implementation, the dispersion unit with an optical metasurface structure can combine the first output light beam along the dispersion direction to obtain the first combined light beam, and the dispersion unit with an optical metasurface structure can also focus the first output light beam along the port direction, so that the wavelength selective switch does not need to be configured with a lens group with a curvature along the port direction, reducing the number of components included in the wavelength selective switch. Similarly, the dispersion unit with an optical metasurface structure can combine the second output light beam along the dispersion direction to obtain the second combined light beam, and the dispersion unit with an optical metasurface structure can also focus the second output light beam along the port direction, so that the wavelength selective switch does not need to be configured with a lens group with a curvature along the port direction, reducing the number of components included in the wavelength selective switch.

[0021] Based on the first aspect, in an optional implementation manner, the nanostructure included in the first region is different from the nanostructure included in the second region, which means at least one of the following:

[0022] The number of nanostructures included in the first region is different from the number of nanostructures included in the second region, the size of the nanostructures included in the first region is different from the size of the nanostructures included in the second region, the arrangement form of the nanostructures included in the first region is different from the arrangement form of the nanostructures included in the second region, and the shape of the nanostructures included in the first region is different from the shape of the nanostructures included in the second region.

[0023] By adopting this implementation, the dispersion unit in the form of an optical metasurface structure can simultaneously have a beam combining effect along the dispersion direction and a focusing effect along the port direction.

[0024] Based on the first aspect, in an optional implementation, the dispersion unit includes a substrate, and a first surface of the substrate includes the optical metasurface structure.

[0025] Based on the first aspect, in an optional implementation manner, the second surface of the substrate includes at least one layer of coating, and the material of the substrate is different from the material of the coating.

[0026] By adopting this implementation, the dispersion unit including the coating can improve the diffraction efficiency in the process of scheduling the transmission direction of the input light beam and reduce the diffraction loss.

[0027] Based on the first aspect, in an optional implementation, the dispersion unit further includes a prism, a first surface of the prism faces the lens group, and a second surface of the prism is connected to a second surface of the substrate.

[0028] In this implementation, the prism is used to adjust the angle at which the first light beam is incident on the optical metasurface structure, thereby ensuring that the multiple second light beams emitted from the dispersion unit are linearly distributed, so that the multiple second light beams can be uniformly emitted from the dispersion unit.

[0029] Based on the first aspect, in an optional implementation, the dispersion unit is used to transmit the collimated multiple second light beams to the optical switching engine, including: the optical metasurface structure is used to reflect the collimated multiple second light beams to the optical switching engine, or the optical metasurface structure is used to transmit the collimated multiple second light beams to the optical switching engine.

[0030] With this implementation, the optical metasurface structure can be transmissive or reflective, thereby achieving flexibility in optical path design during input light beam scheduling.

[0031] In a second aspect, an embodiment of the present application provides an optical switching node, the optical switching node comprising a plurality of wavelength selective switches, two different wavelength selective switches being connected via optical fibers, the wavelength selective switches being as described in the first aspect above, and details thereof are omitted.

[0032] In a third aspect, an embodiment of the present application provides a communication system, comprising an outer shell, the outer shell fixing a processing chip, an optoelectronic conversion module and a wavelength selection switch, the processing chip, the optoelectronic conversion module and the wavelength selection switch being connected in sequence, and the wavelength selection switch being as described in any one of the first aspects above; the processing chip being used to send a service electrical signal to the optoelectronic conversion module; the optoelectronic conversion module being used to convert the service electrical signal into the input light beam; and the wavelength selection switch being used to schedule the transmission direction of the input light beam to emit the output light beam.

[0033] In a fourth aspect, the present application provides an optical network, which includes a first communication system and a second communication system. For descriptions of the first communication system and the second communication system, please refer to the description of the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A structural example diagram of an optical switching node provided in this application;

[0035] Figure 2 This is a structural example diagram of an existing WSS;

[0036] Figure 3 An example diagram of the overall structure of the first embodiment of the WSS provided in this application;

[0037] Figure 4 This is a diagram showing an example of the structure of the WSS provided in this application in the second plane;

[0038] Figure 5 This is a diagram showing an example of the structure of the WSS provided in this application in the third plane;

[0039] Figure 6 An example diagram of the structure of an embodiment of the dispersion unit provided in the present application;

[0040] Figure 7a This is a diagram showing an example structure of the first embodiment of the nanorod provided in this application;

[0041] Figure 7b A diagram showing a second example structure of a nanorod provided in this application;

[0042] Figure 7c This is a structural example diagram of the third embodiment of the nanorod provided in this application;

[0043] Figure 7d This is a structural example diagram of the fourth embodiment of the nanorod provided in this application;

[0044] Figure 8 An example diagram of the overall structure of the second embodiment of the WSS provided in this application;

[0045] Fig. 9 This is an example diagram of the structure of an embodiment of the optical network provided in this application. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0047] The present application provides an optical switching node, which is used to implement the scheduling of the transmission direction of a light beam. The optical switching node can be a reconfigurable optical add drop multiplexer (ROADM) or an optical cross connection (OXC). The optical switching node mainly performs wavelength-level scheduling on the transmission direction of the light beam through WSS.

[0048] Combination Figure 1 The structure of the optical switching node provided by the present application is illustrated as shown, wherein: Figure 1 This is a structural example diagram of an optical switching node provided in this application. This example takes the optical switching node as a ROADM as an example for illustrative description. This example does not limit the specific network structure of the ROADM. For example, the ROADM can adopt a chain, ring, mesh network, etc. Figure 1 The network structure of ROADM using a mesh network is used as an example for illustrative explanation.

[0049] This example takes the ROADM including eight WSSs (ie, WSS1, WSS2 to WSS8) as an example, and the eight WSSs are located at different positions. This example does not limit the number of WSSs included in the ROADM and the positions of each WSS. The WSSs located at different positions are used to schedule the transmission direction of the light beam.

[0050] Taking WSS1 as an example, WSS1 can send a light beam to any WSS included in the ROADM and connected to WSS1 through an optical fiber to realize the scheduling of light beams in different transmission directions. For example, in the ROADM, WSS4, WSS6 and WSS8 are connected to WSS1 through an optical fiber, then WSS1 can send a light beam to any WSS among WSS4, WSS6 and WSS8. This example is illustrated by taking the example that WSS1 is connected to WSS4, WSS6 and WSS8 through an optical fiber, without limitation. In other examples, WSS1 can also be connected to any WSS among WSS2, WSS3, WSS5 and WSS7 included in the ROADM through an optical fiber.

[0051] The following continues to take WSS1 and WSS4 as examples to explain the process of scheduling the transmission direction of the light beam:

[0052] The first light beam 111 transmitted along the direction 101 is input to WSS1 via the input optical fiber of WSS1, and the second light beam 112 is output via the output optical fiber of WSS1 after WSS1 schedules the light beam transmission direction. The output optical fiber of WSS1 is connected to WSS4 via an optical fiber, and WSS1 sends the second light beam 112 to WSS4. The second light beam 112 is output from an output optical fiber included in WSS4, and the second light beam 112 output from WSS4 is transmitted along the direction 102. The direction 101 shown in this example is different from the direction 102. It can be seen that Figure 1 The ROADM shown can achieve the purpose of scheduling the transmission direction of the first light beam 111 from direction 101 to direction 102 .

[0053] It can be understood that the optical switching engine included in the WSS is used to deflect the transmission direction of any input wavelength or any group of wavelengths, so that the deflected wavelength is output from any output optical fiber.

[0054] To better understand the WSS provided in the embodiment of the present application, the following first combines Figure 2 The existing WSS is shown. Figure 22 is a structural example diagram of an existing WSS. The existing WSS includes an optical fiber array 201, a spot shaping and polarization beam splitting component 202, a dispersion direction lens 203, a port direction lens 204, a prism 205, and an optical switching engine 206. An input light beam 211 is input to the WSS through an input optical fiber in the optical fiber array 201. The spot shaping and polarization beam splitting component 202 shapes and processes the polarization state of the input light beam 211 to output a processed light beam 212. The dispersion direction lens 203 and the port direction lens 204 collimate the processed light beam 212 along the dispersion direction and the port direction, respectively, to obtain a collimated light beam 213. The prism 205 disperses the collimated light beam 213 to obtain multiple sub-beams, such as sub-beam 214 and sub-beam 215. The port direction lens 204 and the dispersion direction lens 203 collimate the sub-beams along the port direction and the dispersion direction, respectively, to obtain collimated sub-beams. The optical switching engine 206 deflects the transmission direction of each collimated sub-beam to obtain multiple deflected sub-beams, for example, deflected sub-beam 216 and deflected sub-beam 217. The dispersion direction lens 203 and the port direction lens 204 focus each deflected sub-beam to obtain a focused sub-beam. The prism 205 combines the focused sub-beams to obtain a combined beam. The port direction lens 204 and the dispersion direction lens 203 focus the combined beam to obtain an output beam, which is transmitted to the output optical fiber included in the optical fiber array, and the output optical fiber is used to emit the output beam. It can be understood that the existing WSS needs to independently configure a dispersion direction lens with curvature in the dispersion direction and a port direction lens with curvature in the port direction, resulting in a large number of components included in the existing WSS, which increases the difficulty of assembling the WSS, resulting in low assembly efficiency and poor integration of the WSS.

[0055] The WSS provided in the embodiment of the present application does not need to be configured with a port direction lens having a curvature in the port direction, which effectively improves the integration of the WSS. The structure of the WSS provided in the embodiment of the present application is described below, wherein: Figure 3 This is an example diagram of the overall structure of the first embodiment of the WSS provided in this application. Figure 4 This is a diagram showing an example of the structure of the WSS provided in this application within the second plane. Figure 5 This is a diagram showing an example of the structure of the WSS provided in this application within the third plane. Figure 3 The WSS shown is located in a coordinate system XYZ with O as the origin. Figure 4 The second plane YOZ specifically includes the Y axis and the Z axis of the XYZ coordinate system. Figure 5 The third plane XOZ specifically includes the X-axis and the Z-axis of the XYZ coordinate system.

[0056] The WSS shown in this embodiment includes a fiber array (FA) 301, a dispersion direction lens group, a dispersion unit 304, and an optical switching engine 305. The fiber array shown in this embodiment includes one or more input optical fibers, and this embodiment does not limit the number of input optical fibers included in the fiber array. The fiber array also includes an output fiber array, and the output fiber array includes multiple output optical fibers. This embodiment does not limit the number of output optical fibers included in the output fiber array. Among them, FA301 is located at a front focal plane or a position near the front focal plane of the dispersion unit 304. The optical switching engine 305 is located at a position near the rear focal plane or the rear focal plane of the dispersion unit 304. Then, FA301, the dispersion unit 304, and the optical switching engine 305 constitute a 2f optical system.

[0057] Optionally, the WSS shown in this embodiment further includes a beam shaping and polarization splitting component 302. The input optical fiber is used to transmit an input light beam 311 to the beam shaping and polarization splitting component 302. The input light beam 311 shown in this embodiment is a WDM signal light. In this embodiment, the transmission direction of the input light beam 311 emitted from the input optical fiber 311 coincides with the Z axis in the XYZ coordinate system as an example. It should be clear that in this embodiment, the transmission direction of the input light beam 311 coincides with the Z axis as an example. In other examples, the transmission direction of the input light beam 311 may also have a certain angle with the Z axis, which is not specifically limited in this embodiment.

[0058] The beam shaping and polarization beam splitting component 302 is used to shape the input beam 311 and adjust the polarization state of the input beam 311. This embodiment does not limit the description of the role of the beam shaping and polarization beam splitting component 302, and corresponding adjustments can be made according to the design of the WSS. For example, the beam shaping and polarization beam splitting component 302 can adjust the spot of the input beam 311 from a circular spot to an elliptical spot, so that the spot of the input beam 311 emitted from the beam shaping and polarization beam splitting component 302 is elliptical, and is used to separate the input beam 311 into two beams with orthogonal polarization states, and adjust the polarization states of the two beams to be consistent, and output from the beam shaping and polarization beam splitting component 302. It should be clear that this embodiment does not limit the spot shape and polarization state of the light beam emitted from the beam shaping and polarization beam splitting component 302. This embodiment does not limit the device type of the beam shaping and polarization splitting component 302. For example, the beam shaping and polarization splitting component 302 may include at least one of a crystal, a prism, a polarization grating, a micro lens array (MLA), a diffraction element, and a lens group.

[0059] The input light beam 311 emitted from the beam shaping and polarization splitting component 302 is transmitted to the dispersion direction lens group. This embodiment does not limit the specific number of lenses included in the dispersion direction lens group. Figure 3 In the example shown, the dispersion direction lens group includes the first lens 303 as an example. Figure 4 as well as Figure 5 In the example shown, the dispersion direction lens group includes a first lens 303 and a second lens 306. Figure 3 In the example shown, the first lens 303 can achieve Figure 4 as well as Figure 5 In the example shown, the functions implemented by the first lens 303 and the second lens 306. The first lens 303 shown in this embodiment is used to collimate the input light beam 311 to obtain the first light beam 312, and transmit the first light beam 312 to the dispersion unit 304. The following describes the process of the first lens 303 collimating the input light beam 311 to obtain the first light beam 312. Specifically, the first lens 303 is used to collimate the input light beam 311 along the dispersion direction to obtain the collimated first light beam 312. This embodiment takes the example that the dispersion direction coincides with the Y axis in the coordinate system XYZ. It should be clear that in other examples, the dispersion direction may also have a certain angle with the Y axis, which is not specifically limited. Along the dispersion direction, the input light beam 311 is incident on the first lens 303 at a first divergence angle, and the first light beam 312 is emitted from the first lens 303 at a second divergence angle. Due to the collimation effect of the first lens 303 on the input light beam 311, the first divergence angle is greater than the second divergence angle. Due to the collimating effect of the first lens 303 shown in this embodiment along the dispersion direction, the first light beam 312 has a very small second divergence angle. The collimating effect of the first lens 303 described in this embodiment causes the waist of the input light beam 311 to be smaller than the waist of the first light beam 312 along the dispersion direction. Among them, along the dispersion direction, the waist of the input light beam 311 refers to the position where the light intensity in the input light beam 311 is the largest along the dispersion direction, and is also the position where the beam diameter of the input light beam 311 is the smallest. At the waist, the light intensity distribution presents the characteristics of a Gaussian distribution. For the description of the waist of the first light beam 312, please refer to the description of the waist of the input light beam 311, and no further details will be given.

[0060] In this embodiment, the first lens 303 is taken as an example of a cylindrical lens having curvature in the dispersion direction. In other examples, the first lens 303 may also be a spherical lens, a spherical cylindrical lens, an aspherical lens or an aspherical cylindrical lens. And the first lens 303 of this embodiment may be a reflective lens (e.g. Figure 3 as shown) or a transmissive lens (e.g. Figure 4 as well as Figure 5 As shown), no specific limitation is given. Figure 4 as well as Figure 5 As shown, Figure 4 The first lens 303 has a curvature along the dispersion direction (eg, coincident with the Y axis), and Figure 5The first lens 303 shown along the port direction (eg, coincident with the X-axis) has no curvature.

[0061] The dispersion unit 304 shown in this embodiment is used to decompose the first light beam 312 irradiated on the dispersion unit 304 into multiple second light beams with different wavelengths. The number of second light beams is not limited in this embodiment. The dispersion unit 304 shown in this embodiment has two functions:

[0062] Function 1: The dispersion unit 304 has a wavelength-based light splitting function.

[0063] Combination Figure 3 as well as Figure 4 As shown, the dispersion unit 304 decomposes the first light beam 311 into a first target light beam 313 and a second target light beam 314 in the second plane YOZ. The wavelength of the first target light beam 313 is different from the wavelength of the second target light beam 314. The first target light beam 313 and the second target light beam 314 emitted from the dispersion unit 304 are dispersed along the dispersion direction. This embodiment takes the coincidence of the dispersion direction with the Y axis in the coordinate system XYZ as an example. In other examples, the dispersion direction may also have a certain angle with the Y axis. It should be clear that this embodiment does not limit the number of second light beams emitted after the first light beam 311 is decomposed by the dispersion unit 304. For example, the first light beam 312 is decomposed into N second light beams by the dispersion effect of the dispersion unit 304 along the dispersion direction. The wavelengths of different second light beams are different. Then, the N second light beams emitted from the dispersion unit are λ1, λ2 to λ N , N is any integer greater than 2.

[0064] Combination Figure 3 as well as Figure 5 As shown, taking the first target beam and the second target beam included in the N-way second beam as an example, in the third plane XOZ, the first target beam 313 is emitted from the dispersion unit 304 at a first emission angle, and the second target beam 314 is emitted from the dispersion unit 304 at a second emission angle. Wherein, the third plane XOZ includes the X-axis and the Z-axis of the XYZ coordinate system. For example, the first emission angle is the angle between the first target beam 313 and the second plane YOZ, and for another example, the first emission angle is the angle between the first target beam 313 and the extension line of the first beam 312 in the third plane XOZ. The second emission angle is the angle between the second target beam 314 and the second plane YOZ plane, and for another example, the second emission angle is the angle between the second target beam 314 and the extension line of the first beam 312 in the third plane XOZ. In this embodiment, the first emission angle is equal to the second emission angle as an example. In other examples, the first emission angle and the second emission angle may also be approximately equal, which will not be described in detail in this embodiment.

[0065] Combination Figure 3 as well as Figure 4 As shown, in the second plane YOZ, the first target beam 313 is emitted from the dispersion unit 304 at a third emission angle, and the second target beam 314 is emitted from the dispersion unit 303 at a fourth emission angle. The second plane YOZ includes the Y axis and the Z axis of the XYZ coordinate system. For example, the third emission angle is the angle between the first target beam 313 and the third plane XOZ. For another example, the third emission angle is the angle between the first target beam 313 and the extension line of the first beam 312 in the second plane YOZ. The fourth emission angle is the angle between the second target beam 314 and the third plane XOZ. For another example, the fourth emission angle is the angle between the second target beam 314 and the extension line of the first beam 312 in the second plane YOZ. The third emission angle shown in this embodiment is different from the fourth emission angle.

[0066] Combination Figures 3 to 5 As shown, it can be understood that, because the third emission angle is different from the fourth emission angle, the optical path of the first target light beam 313 and the optical path of the second target light beam 314 have different projection directions in the second plane YOZ. Specifically, multiple mutually parallel projection lines illuminate the optical path of the first target light beam 313 to form a first orthographic projection in the second plane YOZ, and each projection line is perpendicular to the second plane YOZ. The transmission direction of the first target light beam 313 is the same as the pointing direction of the first orthographic projection, for example, Figure 4The transmission direction of the first target beam 313 shown is toward the second lens 306, so the pointing direction of the first orthographic projection is also toward the second lens 306. Multiple mutually parallel projection lines illuminate the optical path of the second target beam 314 to form a second orthographic projection in the second plane YOZ. The transmission direction of the second target beam 314 is the same as the pointing direction of the second orthographic projection. The optical path of the first target beam 313 and the optical path of the second target beam 314 shown in this embodiment have different projection directions in the second plane YOZ, which means that the pointing direction of the first orthographic projection is different from the pointing direction of the second orthographic projection, that is, there is an angle between the first orthographic projection and the second orthographic projection in the second plane YOZ. Since the first exit angle is equal to the second exit angle, the optical path of the first target beam 313 and the optical path of the second target beam 314 have the same projection direction in the third plane XOZ. Specifically, multiple mutually parallel projection lines illuminate the optical path of the first target beam 313 to form a third orthographic projection in the third plane XOZ, and each projection line is perpendicular to the third plane XOZ. The transmission direction of the first target light beam 313 is the same as the pointing direction of the third orthographic projection. Multiple mutually parallel projection lines illuminate the optical path of the second target light beam 314 to form a fourth orthographic projection in the third plane XOZ. The transmission direction of the second target light beam 314 is the same as the pointing direction of the fourth orthographic projection. The optical path of the first target light beam 313 and the optical path of the second target light beam 314 shown in this embodiment have the same projection direction in the third plane XOZ, which means that the pointing direction of the third orthographic projection is the same as and coincides with the pointing direction of the fourth orthographic projection.

[0067] Function 2: the dispersion unit 304 has the function of collimating each second light beam along the port direction.

[0068] Taking the example that the port direction shown in this embodiment coincides with the X-axis in the coordinate system XYZ, in other examples, the port direction may also have a certain angle with the X-axis, which is not specifically limited. In the third plane XOZ, the first light beam 312 is incident on the dispersion unit 304 at a third divergence angle, and the first target light beam 313 is emitted from the dispersion unit 304 at a fourth divergence angle. The first light beam 312 is collimated along the port direction by the dispersion unit 304, so the third divergence angle is greater than the fourth divergence angle. Through the collimation of each second light beam along the port direction by the dispersion unit 304, each second light beam can be collimated along the port direction and then transmitted to the optical switching engine 305. For the description of the collimation of the dispersion unit 304 along the port direction, please refer to the description of the collimation of the first lens 303 along the dispersion direction, which will not be described in detail.

[0069] The structure of the dispersion unit 304 for implementing the above-mentioned functions 1 and 2 is described below:

[0070] Optional structure 1 of the dispersion unit 304:

[0071] The following combination Figure 3 as well as Figure 6 FIG. 4 illustrates the structure of the dispersion unit 304 provided in this embodiment, wherein: Figure 6 An example diagram of the structure of an embodiment of the dispersion unit provided in the present application. The dispersion unit 304 shown in this embodiment includes a substrate 601, wherein the substrate 601 has a first surface and a second surface, the second surface of the substrate 601 faces the first lens 303, and the first surface of the substrate 601 includes an optical metasurface structure 610. It should be clarified that in this embodiment, the first surface of the substrate 601 includes the optical metasurface structure 610 as an example. In other examples, the optical metasurface structure 610 may also be located on the second surface of the substrate 601. The optical metasurface structure 610 realizes the light splitting function of the dispersion unit 304 shown in the above-mentioned function 1 and the function of collimating each second light beam along the port direction shown in function 2. Specifically, the optical metasurface structure 610 includes a plurality of nanostructures arranged along the first plane XOY, and each nanostructure may be a nanosheet (Nanofin) or a nanopillar (Nanopillar). This embodiment takes each nanostructure as a nanopillar as an example. For example, Figure 7a This is an example diagram of the structure of the first embodiment of the nanocolumn provided in this application. Figure 7a The nanorods 701 included in the dispersion unit 304 shown may be square rods. Figure 7b This is a diagram showing an example structure of the second embodiment of the nanorod provided in this application. Figure 7b The nanorods 702 included in the dispersion unit 304 shown may be cross-shaped rods. Figure 7c This is a structural example diagram of the third embodiment of the nanocolumn provided in this application. Figure 7c The nanocolumn 703 included in the dispersion unit 304 shown may be cylindrical. It should be noted that the present embodiment does not limit the description of the nanocolumn structure. In other examples, the nanocolumn may also be an elliptical column, a triangular column or a square column, etc. The optical metasurface structure 610 composed of a plurality of nanocolumns is an artificial composite material with a nanostructure, which greatly reduces the weight and thickness of the dispersion unit 304. Moreover, the dispersion unit 304 decomposes the first light beam 311 into multiple second light beams based on the optical metasurface structure 610, and the height of the nanostructure included in the optical metasurface structure 610 is usually at a sub-wavelength level. Therefore, it is possible to achieve the splitting of the first light beam (such as function 1 mentioned above) and the collimation of each second light beam along the port direction (such as function 2 mentioned above) while reducing the distortion of the first light beam 311. See further. Figure 6As shown, the optical metasurface structure 610 specifically includes a plurality of nanostructures arranged in the dispersion direction and a plurality of nanostructures arranged along the port direction. The optical metasurface structure 610 is equivalent to a refractive index distribution capable of realizing the above-mentioned functions 1 and 2 based on the refractive index distribution of the plurality of nanostructures included.

[0072] Specifically, the dispersion unit 304 shown in this embodiment includes M units, each unit includes at least one nanostructure, and M is any integer greater than 1. For example, the value of M shown in this embodiment can be any value such as 2000 or 10000. This embodiment takes the example that each unit includes one nanostructure. The M units include a first unit and a second unit, and the first nanostructure included in the first unit is different from the second nanostructure included in the second unit. The first unit and the second unit are any two units among the M units. The first nanostructure included in the first unit is different from the second nanostructure included in the second unit, which means at least one of the following:

[0073] The number of first nanostructures included in the first unit is different from the number of second nanostructures included in the second unit, the size of the first nanostructure is different from the size of the second nanostructure, the arrangement form of the first nanostructure is different from the arrangement form of the second nanostructure, and the shape of the first nanostructure is different from the shape of the second nanostructure.

[0074] Among them, the size of the first nanostructure includes the height of the first nanostructure and / or the cross-sectional diameter of the first nanostructure. The height of the first nanostructure refers to the height of the first nanostructure along the Z-axis direction in the XYZ coordinate system. The cross-section of the first nanostructure refers to the cross-section obtained by cutting the first nanostructure with a plane parallel to the first plane XOY as the section plane. For the description of the size of the second nanostructure, please refer to the description of the size of the first nanostructure, and the details are not repeated here. The arrangement form of the first nanostructure refers to the density of the first nanostructure included in the first unit, and / or the distance between two adjacent first nanostructures included in the first unit. For the description of the arrangement form of the second nanostructure, please refer to the description of the arrangement form of the first nanostructure, and the details are not repeated here. For the description of the shape of the first nanostructure, please refer to Figures 7a to 7c As shown, the details are not repeated here.

[0075] Optional structure 2 of the dispersion unit 304:

[0076] Continue to see Figure 6As shown, the dispersion unit 304 also includes a prism 620, the first surface of the prism 620 faces the first lens, and the second surface of the prism 620 is connected to the second surface of the substrate 601. Specifically, the second surface of the prism 620 is bonded to the second surface of the substrate 601 by optical glue or the like. The prism 620 shown in this embodiment is used to adjust the angle at which the first light beam 312 is incident on the optical metasurface structure 610, thereby ensuring that the multiple second light beams emitted from the dispersion unit 304 are linearly distributed, so that the multiple second light beams can be uniformly emitted from the dispersion unit 304. Among them, the linear distribution of the multiple second light beams means that, among the multiple second light beams emitted from the dispersion unit 304, the angle between any two adjacent second light beams is within a preset angle range. For example, taking the preset range of 15 degrees as an example, N second light beams are emitted from the dispersion unit 304, specifically λ1, λ2 to λ N , N is any integer greater than 2. The angle between λ1 and λ2 emitted from the dispersion unit 304 is 0.1 degrees. By analogy, the angle between λ1 and λ2 emitted from the dispersion unit 304 is 0.1 degrees. N-1 With λ N The angle between them is also 15 degrees, and the multiple second light beams emitted from the dispersion unit 304 are linearly distributed. It should be noted that the present embodiment takes the prism 620 as a triangular prism as an example, and is not specifically limited thereto. For example, the prism 620 may also be a right-angle prism or a pentagonal prism.

[0077] Optional structure 3 of the dispersion unit 304:

[0078] Figure 7d This is a structural example diagram of the fourth embodiment of the nanocolumn provided in the present application. Based on the optional structure 1 or the optional structure 2 of the above-mentioned dispersion unit 304, the second surface of the substrate 601 includes at least one layer of coating 710, and the material of the substrate 601 shown in this embodiment is different from the material of the coating 710. For example, the substrate 601 can be made of silicon (Si) or silicon dioxide (SiO2), etc., and the coating 710 can be silicon nitride (Si3N4) or titanium dioxide (TiO2), etc. The dispersion unit 304 including the coating can improve the diffraction efficiency in the process of scheduling the transmission direction of the input light beam and reduce the diffraction loss.

[0079] The dispersion unit 304 shown in this embodiment can make different nanostructures produce different propagation modes or resonance modes through at least one of the size, distribution form or shape of each nanostructure. When the first light beam passes through the nanostructures with different propagation modes or resonance modes, the second light beams emitted from the optical metasurface structure will have different phases. In this embodiment, the dispersion unit 304 is a reflective type as an example, that is, the optical metasurface structure included in the dispersion unit 304 is a reflective optical metasurface structure. Then, when the first light beam passes through the nanostructures with different propagation modes or resonance modes, the second light beams reflected from the optical metasurface structure will have different reflection phases, and the reflectivity will be effectively improved. At least one of the optical metasurface structure and the substrate shown in this embodiment is used to realize a reflective optical metasurface structure. For example, the optical metasurface structure can be made reflective by adjusting the material, arrangement form or shape of the nanostructures included in the optical metasurface structure. For another example, the optical metasurface structure can be made reflective by adjusting the substrate material.

[0080] This embodiment can change the phase distribution of the optical metasurface structure by adjusting the size of the nanostructure. For example, the size of the nanostructures included in the optical metasurface structure is in the order of small to large, and the phase change range can cover the phase change of 0-2π. It can be understood that by setting the size of the nanostructure, the phase distribution of the optical metasurface structure can be adjusted, and the dispersion unit can decompose the first light beam along the dispersion direction to obtain multiple second light beams, and the transmission direction of each second light beam emitted by the dispersion unit can be accurately controlled, thereby achieving the purpose of collimating each second light beam along the port direction. The above example takes the dispersion unit adjusting the phase distribution of the optical metasurface structure by adjusting the size of the nanostructure as an example. In other examples, the phase distribution of the optical metasurface structure can also be adjusted by adjusting at least one of the size, arrangement or shape of the nanostructure.

[0081] The multiple second light beams emitted from the dispersion unit 304 are transmitted to the dispersion direction lens group, and the dispersion direction lens group is used to focus each second light beam along the dispersion direction to obtain multiple third light beams. Figure 3 The first lens 303 shown focuses the first target beam 313 to obtain a third beam 315, and the first lens 303 focuses the second target beam 314 to obtain a third beam 316. Figure 4 as well as Figure 5In the example shown, the second lens 306 focuses the first target beam 313 to obtain the third beam 315, and the second lens 306 focuses the second target beam 314 to obtain the third beam 316. The focusing effect of the second lens 306 described in this embodiment causes the waist of the first target beam 313 to be larger than the waist of the third beam 315 along the dispersion direction. For the description of the waist, please refer to the above description of the waist of the first beam 312, which will not be described in detail. Figure 3 as well as Figure 4 As shown, in the second plane YOZ, the third light beam 315 and the third light beam 316 are transmitted to the optical switching engine 305 along different directions respectively. The third light beam 315 is irradiated into the first exchange area of ​​the optical switching engine 305 to form a first light spot 351, and the third light beam 316 is irradiated into the second exchange area of ​​the optical switching engine 305 to form a second light spot 352. Due to the collimation effect of the dispersion unit 304 along the port direction and the focusing effect of the dispersion direction lens group along the dispersion direction, the positions of the first light spot 351 and the second light spot 352 are separated from each other in the second plane YOZ. Figure 3 as well as Figure 5 As shown, in the third plane XOZ, the third light beam 315 and the third light beam 316 are transmitted to the optical switching engine 305 along the same direction. In the third plane XOZ, the positions of the first light spot 351 and the second light spot 352 at least partially overlap. The surface of the optical switching engine 305 shown in this embodiment is parallel to the third plane XOZ. It can be understood that after the collimation effect of the dispersion unit 304 along the port direction and the focusing effect of the dispersion direction lens group along the dispersion direction, the optical switching engine 305 receives N wavelengths, which are λ1, λ2 to λ N N light spots will be formed when N wavelengths are irradiated on the optical switching engine 305. In the third plane XOZ, the positions of the N light spots at least partially overlap. In the second plane YOZ, the positions of the N light spots are separated from each other.

[0082] The optical switching engine 305 shown in this embodiment is used to deflect the transmission direction of each third light beam, so that the optical switching engine 305 emits multiple output light beams with deflected transmission directions. The optical switching engine 305 shown in this embodiment can be liquid crystal on silicon (LCOS), liquid crystal (LC) array chip, micro electromechanical system (MEMS), digital light processor (DLP), or dual-axis MEMS. In this embodiment, the optical switching engine 305 is taken as LCOS. By applying a first voltage to the first switching area of ​​the optical switching engine 305, the refractive index of the first switching area is changed, thereby deflecting the transmission direction of the third light beam 315 along the port direction to emit the first output light beam 361. By applying a second voltage to the second switching area of ​​the optical switching engine 305, the refractive index of the second switching area is changed, thereby deflecting the transmission direction of the third light beam 316 along the port direction to emit the second output light beam 362. If the optical switching engine 305 shown in this embodiment is a MEMS, and the third light beam 315 is incident on the first reflective lens included in the MEMS, and the third light beam 316 is incident on the second reflective lens included in the MEMS. By controlling the rotation of the first reflective lens and the second reflective lens, the first output light beam 361 and the second output light beam 362 are respectively emitted from the MEMS at different emission angles. If the optical switching engine 305 shown in this embodiment is a dual-axis MEMS, the dual-axis MEMS is emitted from the optical switching engine 305 at different emission angles based on the wavelengths of the first output light beam 361 and the second output light beam 362.

[0083] The output fiber array shown in this embodiment includes a plurality of output fibers. This embodiment does not limit the number of output fibers included in the output fiber array. For example, the output fiber array includes a first output fiber and a second output fiber. In the second plane YOZ, the positions of the first output fiber and the second output fiber overlap, and in the third plane XOZ, the positions of the first output fiber and the second output fiber are separated. That is, along the port direction, the position of the first output fiber is different from the position of the second output fiber. It should be clear that the description of the arrangement of the output fiber array in this embodiment is an optional example and is not limited. For example, the output fiber has a certain curvature along the dispersion direction. For example, the positions of the multiple output fibers included in the output fiber array can be randomly arranged. For example, the multiple output fibers included in the output fiber array are arranged in a two-dimensional form.

[0084] In this embodiment, taking the first output beam 361 emitted from the optical switching engine 305 as an example, which is deflected to the first output fiber of the output fiber array, and the second output beam 362 emitted from the optical switching engine 305 as an example, the optical switching engine 305 deflects the transmission direction of the third beam 315 at a first deflection angle to emit the deflected first output beam 361, and the optical switching engine 305 deflects the transmission direction of the third beam 316 at a second deflection angle to emit the deflected second output beam 362, wherein the first deflection angle corresponds to the position of the first output fiber, and the second deflection angle corresponds to the position of the second output fiber, so that the first output beam 361 emitted from the optical switching engine 305 can be transmitted to the first output fiber, and the second output beam 362 emitted from the optical switching engine 305 can be transmitted to the second output fiber. Specifically, the first deflection angle can be the angle between the transmission direction of the third beam 315 and the transmission direction of the first output beam 361. The second deflection angle may be the angle between the transmission direction of the third light beam 316 and the transmission direction of the second output light beam 362. Figure 5 In the third plane XOZ shown, the first deflection angle is different from the second deflection angle. Figure 4 In the second plane YOZ shown, the first deflection angle and the second deflection angle may be the same. The magnitudes of the first deflection angle and the second deflection angle shown in this embodiment are related to the arrangement positions of the first output optical fiber and the second output optical fiber in the output optical fiber array.

[0085] The first output light beam 361 and the second output light beam 362 emitted from the optical switching engine 305 are transmitted to the second lens 306. The second lens 306 is used to collimate each output light beam along the dispersion direction, and send the collimated first output light beam 361 and the second output light beam 362 to the dispersion unit 304. The collimation effect of the second lens 306 described in this embodiment causes the waist of the first output light beam 361 to be greater than the waist of the collimated first output light beam 361 along the dispersion direction. For the description of the waist, please refer to the above description of the waist of the input light beam 311, which will not be described in detail. For the description of the collimation of the second output light beam 362 by the second lens 306 along the dispersion direction, please refer to the description of the collimation of the first lens 306 along the dispersion direction, which will not be described in detail.

[0086] The dispersion unit 304 receives the first output beam 361 and the second output beam 362 from the second lens 306 . The dispersion unit 304 has two functions.

[0087] Function 3: the dispersion unit 304 has a wavelength-based beam combining function.

[0088] For example, the dispersion unit 304 receives N output light beams from the second lens 306, and the wavelengths of the N output light beams are λ1, λ2, λ3, λN-1, and λN, respectively. It should be noted that the present embodiment does not limit the value of N. In this example, the wavelength of the first output light beam 361 may be λ1, and the wavelength of the second output light beam 362 may be λN. The optical metasurface structure of the dispersion unit 304 includes multiple regions, and the multiple regions specifically include a first region and a second region. The first region is used to transmit the output light beam to the first output optical fiber, and the second region is used to transmit the output light beam to the second output optical fiber. Among them, in Figure 4 In the second plane YOZ shown in FIG. , since the positions of the first output optical fiber and the second output optical fiber coincide with each other, the first region and the second region of the optical metasurface structure included in the dispersion unit 304 coincide with each other in the second plane YOZ. Figure 5 In the third plane XOZ shown, because the positions of the first output optical fiber and the second optical fiber are separated, the first region and the second region of the optical metasurface structure included in the dispersion unit 304 are separated in the third plane XOZ. If λ1, λ2 and λ3 need to be emitted from the first output optical fiber, λ1, λ2 and λ3 emitted from the second lens 306 are transmitted to the first region of the optical metasurface structure. If λN-1 and λN need to be emitted from the second output optical fiber, λN-1 and λN emitted from the second lens 306 are transmitted to the second region of the optical metasurface structure. The first region of the optical metasurface structure is used to combine λ1, λ2 and λ3 to obtain a first combined light beam 371. The second region of the optical metasurface structure is used to combine λN-1 and λN to obtain a second combined light beam 372. The first region and the second region shown in this embodiment respectively include a plurality of nanostructures. For the description of the nanostructures, please refer to the above description of function 1 and function 2 of the dispersion unit 304, and no further description is given.

[0089] Function 4: the dispersion unit 304 has the function of focusing each combined light beam along the port direction.

[0090] Since the dispersion unit 304 shown in this embodiment has a curvature along the port direction, the dispersion unit 304 shown in this embodiment can focus each combined light beam. For specific instructions on focusing along the dispersion direction, please refer to the instructions on focusing along the port direction by the second lens 306, and the details are not repeated here.

[0091] The first region and the second region of the dispersion unit shown in this embodiment are to realize the above-mentioned functions 3 and 4, and the nanostructure included in the first region shown in this embodiment is different from the nanostructure included in the second region. The nanostructure included in the first region is different from the nanostructure included in the second region, which means at least one of the following:

[0092] The number of nanostructures included in the first region is different from the number of nanostructures included in the second region, the size of the nanostructures included in the first region is different from the size of the nanostructures included in the second region, the arrangement form of the nanostructures included in the first region is different from the arrangement form of the nanostructures included in the second region, and the shape of the nanostructures included in the first region is different from the shape of the nanostructures included in the second region. For the description of the number, size, arrangement form and shape of the nanostructures, please refer to the description of the number, size, arrangement form and shape of the first nanostructures included in the first unit shown above, and no further details will be given.

[0093] The first combined light beam 371 and the second combined light beam 372 emitted from the dispersion unit 304 are transmitted to the first lens 303, and the first lens 303 is used to focus the first combined light beam 371 to the first output optical fiber along the dispersion direction, and the first lens 303 is also used to focus the second combined light beam 372 to the second output optical fiber along the dispersion direction. For the description of the focusing of the first lens 303 along the dispersion direction, please refer to the description of the focusing of the dispersion unit 304 along the port direction, and the details are not repeated. In this embodiment, the first output optical fiber is different from the second output optical fiber as an example. In other examples, the first output optical fiber and the second output optical fiber can be the same output optical fiber.

[0094] By adopting the WSS shown in this embodiment, the WSS can dispatch any wavelength input by the input optical fiber to any output optical fiber included in the output optical fiber array, so as to achieve the purpose of independently dispatching any wavelength to any output port. Moreover, the dispersion unit is a device, which has the functions of splitting along the dispersion direction and collimating along the port direction. Moreover, the dispersion unit also has the functions of combining along the dispersion direction and focusing along the port direction. Then, the WSS shown in this embodiment does not need to be configured with a lens group with curvature along the port direction, which reduces the number of components included in the WSS, reduces the difficulty of assembling the WSS, and improves the assembly efficiency of assembling the WSS and the integration of the WSS. Because the WSS shown in this embodiment does not need to be configured with a lens group with curvature along the port direction, the complexity of the optical path in the process of WSS scheduling the light beam is simplified, and the accuracy of scheduling the light beam transmission direction is improved. The optical metasurface structure of the dispersion unit shown in this embodiment is made of nanostructures, which improves the diffraction efficiency and reduces the insertion loss of the WSS.

[0095] Figure 3 As shown, the optical metasurface structure included in the dispersion unit is a reflective optical metasurface structure as an example. Figure 8 The optical metasurface structure included in the dispersion unit is taken as an example as a transmissive optical metasurface structure, wherein: Figure 8 This is an example diagram of the overall structure of the second embodiment of the WSS provided in this application.

[0096] The WSS shown in this embodiment includes FA801, beam shaping and polarization splitting component 802, dispersion direction lens group 803, dispersion unit 804 and optical switching engine 805. For the description of FA801, beam shaping and polarization splitting component 802, dispersion direction lens group 803 and optical switching engine 805 shown in this embodiment, please refer to Figure 3 The corresponding instructions are not elaborated in detail.

[0097] The input optical fiber included in FA801 transmits the input light beam 811 to the dispersion direction lens group 803. The dispersion direction lens group 803 collimates the input light beam 811 along the dispersion direction to obtain a collimated first light beam 812. The dispersion direction lens group 803 is used to transmit the first light beam 812 to the dispersion unit 804. For a description of the specific process, please refer to Figures 3 to 5 The corresponding dispersion unit receives the first light beam process, which is not described in detail. The dispersion unit 804 shown in this embodiment is used to decompose the first light beam 812 irradiated on the dispersion unit 804 into multiple second light beams with different wavelengths, and collimate each second light beam along the port direction. For a detailed description of the decomposition and collimation process, please refer to Figures 3 to 5 The corresponding dispersion unit decomposes the first light beam to obtain multiple second light beams and performs the collimation process, which will not be described in detail.

[0098] The multiple second light beams shown in this embodiment specifically include a first target light beam 813 and a second target light beam 814. The optical metasurface structure included in the dispersion unit 804 is a transmissive optical metasurface structure. Then, the first target light beam 813 and the second target light beam 814 decomposed by the dispersion unit 804 are transmitted from the dispersion unit 804 and transmitted to the optical switching engine 805. If the dispersion unit 804 is transmissive, then when the first light beam passes through nanostructures with different propagation modes or resonance modes, the second light beams transmitted from the optical metasurface structure will have different transmission phases, and the transmittance will be effectively improved. The dispersion unit 804 shown in this embodiment can make different nanostructures produce different propagation modes or resonance modes through at least one of the size, distribution form or shape of each nanostructure. When the first light beam passes through nanostructures with different propagation modes or resonance modes, the second light beams transmitted from the optical metasurface structure will have different phases. At least one of the optical metasurface structure and the substrate shown in this embodiment is used to realize the transmission of the second light beam. For example, the optical metasurface structure may be made transmissive by adjusting the material, arrangement or shape of the nanostructures included in the optical metasurface structure. For another example, the optical metasurface structure may be made transmissive by adjusting the substrate material. Figure 3 The corresponding dispersion unit structure is not described in detail.

[0099] The first target light beam 813 and the second target light beam 814 emitted from the dispersion unit 804 are collimated and transmitted to the optical switching engine 805. The optical switching engine 805 is used to deflect the transmission direction of each second light beam, so that the optical switching engine 805 emits a plurality of output light beams whose transmission directions are deflected. The optical switching engine 805 deflects the transmission direction of the second light beam 813 at a first deflection angle to emit the deflected first output light beam 815, and the optical switching engine 805 deflects the transmission direction of the second target light beam 814 at a second deflection angle to emit the deflected second output light beam 816, wherein the first deflection angle corresponds to the position of the first output optical fiber, and the second deflection angle corresponds to the position of the second output optical fiber. For a description of the first deflection angle and the second deflection angle, please refer to Figures 3 to 5 The first output beam 815 and the second output beam 816 emitted from the optical switching engine 805 are transmitted to the dispersion unit 804. The dispersion unit 804 is used to combine the first output beam 815 to obtain a first combined beam 817. The dispersion unit 804 is also used to combine the second output beam 816 to obtain a second combined beam 818. For the description of the combination of the dispersion unit 804, please refer to Figures 3 to 5 The first combined light beam 817 is transmitted to the first output optical fiber to be emitted from the WSS, and the second combined light beam 818 is transmitted to the second output optical fiber to be emitted from the WSS. For the specific process, please refer to Figures 3 to 5 The process of outputting the corresponding combined light beam from the output optical fiber is not described in detail.

[0100] By using the WSS shown in this embodiment, the WSS can dispatch any wavelength input by the input optical fiber to any output optical fiber included in the output optical fiber array, so as to achieve the purpose of independently dispatching any wavelength to any output port. Moreover, the dispersion unit is a device, which has the functions of splitting and collimating each second light beam along the port direction, and the dispersion unit also has the functions of combining and focusing each light beam along the port direction. Therefore, the WSS shown in this embodiment does not need to be configured with a lens group with curvature along the port direction, which reduces the number of components included in the WSS, reduces the difficulty of assembling the WSS, and improves the assembly efficiency of the WSS and the integration of the WSS. Because the WSS shown in this embodiment does not need to be configured with a lens group with curvature along the port direction, the complexity of the optical path in the process of WSS scheduling the light beam is simplified, and the accuracy of scheduling the light beam transmission direction is improved. Because the optical metasurface structure is made of nanostructures, the diffraction efficiency is improved and the insertion loss of the WSS is reduced.

[0101] The present application also provides an optical switching node. For a description of the optical switching node, see Figure 1 The corresponding instructions are not elaborated in detail.

[0102] The present application also provides an optical network. The structure of the optical network can be seen in Fig. 9 As shown, Fig. 9 This is an example diagram of the structure of an embodiment of the optical network provided in this application.

[0103] The optical network 900 provided in the present application specifically includes a first communication system 901 and a second communication system 902, and the first communication system 901 and the second communication system 902 are connected by an optical fiber. This example does not limit the number of communication systems included in the optical network 900. For example, the first communication system 901 can be connected to multiple second communication systems 902 through an optical splitter. This example does not limit the networking type of the optical network. For example, the optical network can adopt a ring network or a star network. This example does not limit the type of network applied to the optical network 900. For example, if the optical network 900 shown in this example is applied to a passive optical network (PON), one of the first communication system 901 and the second communication system 902 can be an optical network unit (ONU) or an optical network terminal (ONT), and the other communication system in the first communication system 901 and the second communication system 902 can be an optical line terminal (OLT). If the optical network 900 is applied to an optical transport network (OTN), the first communication system 901 and the second communication system 902 may both be OTN devices. The optical network 900 shown in this example may also be applied to a data center network (DCN) or a metropolitan area network, etc., without specific limitation. Taking the first communication system 901 as an example, this example does not limit the device type of the first communication system 901. For example, the first communication system 901 may be an optical transmission device, an optical access device, a router, a switch, a wireless base station, a wireless remote access device, a wireless baseband signal processing device, etc., or a computing server (usually referred to as a server), a high-performance computer (HPC), a storage server, or a memory resource pool, etc. This example does not limit the type of the first communication system 901, as long as the first communication system 901 has an electro-optical conversion function and an optical interface that can be connected to an optical fiber. For the description of the type of the second communication system 902, please refer to the description of the first communication system 901, and no further details will be given.

[0104] Taking the first communication system 901 as an example, the first communication system 901 includes an outer shell, and the outer shell fixes a device and one or more optoelectronic conversion modules. The outer shell also fixes one or more WSSs connected to the optoelectronic conversion module. Among them, the optoelectronic conversion module can also be referred to as an optical transceiver module or an optical module, etc. This example does not limit the number of devices included in the first communication system 901. The device and the first communication system 901 are integrated devices, or the device is an independent pluggable single board. This example does not limit the number of optoelectronic conversion modules included in the first communication system 901. The optoelectronic conversion module can be integrated with the device or can be plugged in a single board of the device, etc., and there is no specific limitation. Specifically, the device has packaged a processing chip and a connector. Among them, the processing chip can be one or more chips, or one or more integrated circuits. For another example, the processing chip may be one or more optical digital signal processors (oDSP), field-programmable gate arrays (FPGA), application-specific integrated circuits (ASIC), systems on chips (SoC), central processor units (CPU), network processors (NP), microcontroller units (MCU), programmable logic devices (PLD), network card chips, storage interface chips or other integrated chips, or any combination of the above chips, or processing modules, etc., which will not be described in detail. The processing chip is connected to the optoelectronic conversion module through a connector, and the optical port of the optoelectronic conversion module is connected to the input optical fiber or output optical fiber of the WSS. For the description of the structure of the second communication system 902, please refer to the description of the structure of the first communication system 901, which will not be described in detail.

[0105] The optoelectronic conversion module described in this embodiment can be connected to one or more WSSs. For the description of the WSS structure, please refer to the above embodiment, and the specific details will not be repeated. The WSS and the optoelectronic conversion module can be an integrated structure. For example, the WSS can be plugged in and out of the optoelectronic conversion module, etc., and the specific details are not limited. In the first communication system 901, the processing chip is used to send a first business electrical signal to the optoelectronic conversion module, and the optoelectronic conversion module is used to convert the first business electrical signal into a first input light beam, and transmit the first input light beam to the input optical fiber of the WSS. The WSS is used to schedule the transmission direction of the first input light beam to emit the output light beam. For a description of the specific process, please refer to the above description of the WSS scheduling the transmission direction of the input light beam, and the specific details will not be repeated. Continuing with the first communication system 901 as an example, the output optical fiber of the WSS receives a second input light beam from another communication system (for example, the second optical communication device 902), and the WSS schedules the transmission direction of the second input light beam to transmit it to the input optical fiber of the WSS. For a description of the specific process, please refer to the description of the WSS scheduling the transmission direction of the first input light beam of the first communication system 901, and the specific details will not be repeated.

[0106] The present application also provides a communication system. The structure of the communication system is shown in Fig. 9 The description of the first communication system or the second communication system shown is not repeated in detail.

[0107] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A wavelength selective switch, characterized in that: include: An input optical fiber, a lens group, a dispersion unit, an optical switching engine, and an output optical fiber array, wherein the dispersion unit includes an optical metasurface structure, and the optical metasurface structure includes a plurality of nanostructures arranged along a first plane; The input optical fiber is used to transmit an input light beam to the lens group, and a transmission direction of the input light beam intersects with the first plane; The lens group is used to collimate the input light beam to obtain a first light beam, and transmit the first light beam to the dispersion unit; The optical metasurface structure is used to decompose the first light beam to obtain multiple second light beams, and the optical metasurface structure is also used to collimate the multiple second light beams to transmit the collimated multiple second light beams to the optical switching engine; The optical switching engine is used to deflect the transmission direction of each of the multiple second light beams to obtain multiple output light beams, and the multiple output light beams are used to be output through the output optical fiber array.

2. The wavelength selective switch according to claim 1, characterized in that: The optical paths of the multiple second light beams emitted from the dispersion unit have different projection directions in the second plane; the optical paths of the multiple second light beams emitted from the dispersion unit have different projection directions in the third plane, and the third plane intersects with the first plane and the second plane respectively.

3. The wavelength selective switch according to claim 2, characterized in that: The lens group is used to collimate the input light beam along a dispersion direction, and the dispersion unit is used to collimate the second light beam along a port direction, wherein the dispersion direction intersects with the third plane, and the port direction intersects with the second plane.

4. The wavelength selective switch according to claim 2 or 3, characterized in that: The multi-path second light beam includes a first target light beam and a second target light beam, the first target light beam forms a first light spot on the optical switching engine, the second target light beam forms a second light spot on the optical switching engine, in the second plane, the positions of the first light spot and the second light spot are separated from each other, and in the third plane, the positions of the first light spot and the second light spot at least partially overlap.

5. The wavelength selective switch according to any one of claims 1 to 4, characterized in that: The optical metasurface structure includes a plurality of units, each of the plurality of units includes at least one nanostructure, the plurality of units include a first unit and a second unit, and the nanostructure included in the first unit is different from the nanostructure included in the second unit.

6. The wavelength selective switch according to claim 5, characterized in that: The nanostructure included in the first unit is different from the nanostructure included in the second unit, which refers to at least one of the following: The number of nanostructures included in the first unit is different from the number of nanostructures included in the second unit, the size of the nanostructures included in the first unit is different from the size of the nanostructures included in the second unit, the arrangement of the nanostructures included in the first unit is different from the arrangement of the nanostructures included in the second unit, and the shape of the nanostructures included in the first unit is different from the shape of the nanostructures included in the second unit.

7. The wavelength selective switch according to claim 5 or 6, characterized in that: The optical metasurface structure includes a plurality of regions, each of the plurality of regions includes a plurality of the units, the plurality of regions include a first region and a second region, and the nanostructure included in the first region is different from the nanostructure included in the second region; The first area is used to receive a first output beam from the optical switching engine, the second area is used to receive a second output beam from the optical switching engine, and the multi-path output beam includes the first output beam and the second output beam; The first region is also used to focus the first output light beam along the port direction, and the focused first output light beam is used to be output through a first output optical fiber. The second region is also used to focus the second output light beam along the port direction, and the focused second output light beam is used to be output through a second output optical fiber. The output optical fiber array includes the first output optical fiber and the second output optical fiber.

8. The wavelength selective switch according to claim 7, characterized in that: The nanostructure included in the first region is different from the nanostructure included in the second region, which refers to at least one of the following: The number of nanostructures included in the first region is different from the number of nanostructures included in the second region, the size of the nanostructures included in the first region is different from the size of the nanostructures included in the second region, the arrangement form of the nanostructures included in the first region is different from the arrangement form of the nanostructures included in the second region, and the shape of the nanostructures included in the first region is different from the shape of the nanostructures included in the second region.

9. The wavelength selective switch according to any one of claims 1 to 8, characterized in that: The dispersion unit includes a substrate, and a first surface of the substrate includes the optical metasurface structure.

10. The wavelength selective switch according to claim 9, characterized in that: The second surface of the substrate includes at least one layer of coating, and the material of the substrate is different from that of the coating.

11. The wavelength selective switch according to claim 9 or 10, characterized in that: The dispersion unit further includes a prism, a first surface of the prism faces the lens group, and a second surface of the prism is connected to the second surface of the substrate.

12. The wavelength selective switch according to any one of claims 1 to 11, characterized in that: The dispersion unit is used to transmit the collimated multi-path second light beams to the optical switching engine, comprising: The optical metasurface structure is used to reflect the collimated multi-path second light beams toward the optical switching engine, or the optical metasurface structure is used to transmit the collimated multi-path second light beams toward the optical switching engine.

13. An optical switching node, characterized in that: The optical switching node comprises a plurality of wavelength selective switches, and two different wavelength selective switches are connected via optical fibers. The wavelength selective switches are as described in any one of claims 1 to 12.

14. A communication system, characterized in that: It comprises an outer shell, the outer shell fixes a processing chip, a photoelectric conversion module and a wavelength selection switch, the processing chip, the photoelectric conversion module and the wavelength selection switch are connected in sequence, and the wavelength selection switch is as claimed in any one of claims 1 to 12; The processing chip is used to send a service electrical signal to the photoelectric conversion module; The photoelectric conversion module is used to convert the business electrical signal into the input light beam; The wavelength selective switch is used to adjust the transmission direction of the input light beam to emit the output light beam.

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