C and L band wavelength selective switch with high output port count

Abstract

The invention relates to a C and L band wavelength selective switch with high output port count. The wavelength selective switch includes a first input configured to provide a first light beam in a first wavelength band; a first output dedicated to the first input; a second input spatially offset from the first input, where the second input is configured to provide a second light beam in a second wavelength band, the second wavelength band not overlapping the first wavelength band; a second output dedicated to the second input; a wavelength dispersion element configured to split the first light beam into a first sub-light beam and split the second light beam into a second sub-light beam; and a beam steering device configured to redirect the first sub-beam in a wavelength selective manner to couple the first sub-beam to one or more of the first outputs, and redirect the second sub-beam in a wavelength selective manner to couple the second sub-beam to one or more of the second outputs.

Description

Cross-references to related applications

[0001] This patent application claims priority to U.S. Provisional Patent Application No. 63 / 708,573, filed October 17, 2024, entitled "HIGH RESOLUTION, WIDE BAND, INTEGRATED INPUT CROSS-CONNECT LINE WAVELENGTH SELECTIVE SWITCH WITH TWO-DIMENSIONAL FIBER ARRAY". The disclosure of the prior application is considered part of this patent application and is incorporated herein by reference. Technical Field

[0002] This disclosure generally relates to wavelength selective switches. Background Technology

[0003] Wavelength selective switches (WSS) are widely used for dynamic routing of wavelength channels in optical communication networks. WSSs can be used in dense wavelength division multiplexing (DWDM) systems, where WSSs enable the routing of specific wavelengths (or channels) of light from one fiber to another. WSS devices can be deployed in optical switching nodes in long-distance, regional, and metropolitan area optical communication networks.

[0004] Long-wavelength bands and conventional bands are typically referred to as L-band and C-band, respectively. There is a growing industrial demand for wide-band (C+L band) and high-port-count WSS devices. These WSS devices require the ability to select flexible optical channel widths affecting the output. Setting the channel width and beam steering of the channel is typically achieved using liquid crystal on silicon (LCOS) chips. LCOS is a miniaturized reflective active-matrix liquid crystal display, or "microdisplay," that uses liquid crystal on top of a silicon substrate. LCOS can also be referred to as spatial light modulators or beam guide arrays. Summary of the Invention

[0005] In some embodiments, the wavelength selective switch includes: a switching engine configured to redirect light; a wavelength dispersive element optically coupled bidirectionally to the switching engine; a first fiber array unit including a first input fiber and a plurality of first output fibers, wherein the first input fibers are capable of supporting a first wavelength band and a second wavelength band, wherein the first input fibers are configured to provide a first beam including a first plurality of wavelength channels in the first wavelength band; and a second fiber array unit including a second input fiber and a plurality of second output fibers, wherein the second output fibers are capable of supporting the first wavelength band and the second wavelength band, wherein the second input fibers are configured to provide a second beam including a second plurality of wavelength channels in the second wavelength band, wherein the first wavelength band and the second wavelength band are mutually exclusive wavelength bands, and wherein the first input fibers and the second input fibers are arranged such that the first beam and the second beam are spatially offset. The components partially overlap; a first imaging element configured to image a first beam and a second beam onto a wavelength dispersive element at an infinite conjugate plane, wherein the wavelength dispersive element is configured to disperse a first plurality of wavelength channels into a first sub-beam group and disperse a second plurality of wavelength channels into a second sub-beam group; and a second imaging element configured to image the first sub-beam group and the second sub-beam group onto a switching engine at a focal plane, wherein the switching engine is configured to redirect the first sub-beam group in a first wavelength selective manner to couple the first sub-beam group to one or more of a plurality of first output fibers, and wherein the switching engine is configured to redirect the second sub-beam group in a second wavelength selective manner to couple the second sub-beam group to one or more of a plurality of second output fibers; and a controller configured to, during a first operation, confine the first beam to a first wavelength band and the second beam to a second wavelength band.

[0006] In some embodiments, the wavelength selective switch includes: a first input configured to provide a first beam in a first wavelength band; a plurality of first outputs dedicated to the first input; a second input spatially offset from the first input, wherein the second input is configured to provide a second beam in a second wavelength band that does not overlap with the first wavelength band; a plurality of second outputs dedicated to the second input; a wavelength dispersive element configured to receive the first beam, receive the second beam, separate the first beam into one or more first sub-beams, and separate the second beam into one or more second sub-beams; and a beam steering device configured to: redirect one or more first sub-beams in a first wavelength selective manner to couple one or more first sub-beams to one or more first outputs of a plurality of first outputs, and redirect one or more second sub-beams in a second wavelength selective manner to couple one or more second sub-beams to one or more second outputs of a plurality of second outputs.

[0007] In some embodiments, a method includes: transmitting a first beam from a first input to a wavelength selective switch, the first beam having a first wavelength component specifically within a first wavelength band; transmitting a second beam from a second input to a wavelength selective switch, the second beam having a second wavelength component specifically within a second wavelength band not overlapping with the first wavelength band; imaging the first beam and the second beam onto a wavelength dispersive element at an infinite conjugate plane by a first imaging element; separating the first wavelength component into a first sub-beam group by the wavelength dispersive element; separating the second wavelength component into a second sub-beam group by the wavelength dispersive element; imaging the first beam group and the second beam group onto a switching engine at a focal plane by a second imaging element; independently redirecting each sub-beam in the first sub-beam group by the switching engine to couple the first sub-beam group to one or more of a plurality of first outputs, wherein the plurality of first outputs are dedicated to the first input; and independently redirecting each sub-beam in the second sub-beam group by the switching engine to couple the second sub-beam group to one or more of a plurality of second outputs, wherein the plurality of second outputs are dedicated to the second input. Attached Figure Description

[0008] Figure 1 A WSS according to one or more embodiments is shown.

[0009] Figure 2 A WSS according to one or more embodiments is shown.

[0010] Figure 3 This is a flowchart of an example process associated with C and L band WSSs having high output port counts. Detailed Implementation

[0011] The following detailed description of the exemplary embodiments refers to the accompanying drawings, in which the same reference numerals in different drawings may identify the same or similar elements.

[0012] The input to a WSS corresponds to the incoming optical signal entering the WSS device. A WSS can provide switching or routing capabilities, where specific wavelengths are selectively routed between fibers or ports. In this sense, a WSS can provide different optical signal paths or port configurations involved in different optical signals cross-connected within a WSS device.

[0013] Current C+L WSS devices, sometimes referred to as integrated C+L band WSS devices, include inputs dedicated to either C-band or L-band light. Therefore, a first input can be used exclusively for C-band light throughout the device's lifetime, and a second input can be used exclusively for L-band light throughout the device's lifetime. In other words, the first input can provide only C-band light, and the second input can provide only L-band light. Multiple outputs can be shared among the inputs, with optics designed to guide both the first and second inputs to either output. However, because the outputs are shared across two different wavelength bands, a band splitter is provided at each output to separate the light into the corresponding C-band and L-band light. The band splitter increases the size, cost, and complexity of the C+L WSS device.

[0014] Some embodiments described herein provide C+L band WSS devices. A C+L band WSS device may include multiple inputs, each naturally designed for both C-band and L-band light. Therefore, each input is capable of supporting the full C+L band spectrum. A C+L band WSS device may include a first input / output device (e.g., a first integrated C and L device) and a second input / output device (e.g., a second integrated C and L device) integrated into a single WSS device, having shared or common optics for beam shaping, wavelength dispersion, and for output steering or switching of light for both the first and second input / output devices. The common optics may include a switching engine for steering the respective light of both input / output devices.

[0015] The first input / output device may include a plurality of first outputs dedicated to the first input. In other words, the plurality of first outputs are optically coupled to the first input and can be arranged to receive light only from light originating from the first input. Additionally, the second input / output may include second outputs dedicated to the second input. In other words, a plurality of second outputs are optically coupled to the second input and can be arranged to receive light only from light originating from the second input. In some examples, the plurality of first outputs and the plurality of second outputs each include 32 outputs to form a 64-output WSS device. Some implementations may relate to high port-count WSS devices, where the maximum number of ports is limited by the steering range of the switching engine.

[0016] The first and second input / output devices can be arranged with a small spatial offset relative to each other, such that light from each input / output device spatially overlaps (but does not completely overlap) as it propagates through a common optics. During operation, the first and second input / output devices can be confined to different wavelength bands, ensuring no wavelength competition between them. For example, the first input / output device can be confined to the C-band, and the second input / output device can be confined to the L-band, and vice versa. In some cases, the controller can configure each input to have a specific wavelength band to ensure no wavelength competition between the first and second input / output devices. Light associated with the first and second input / output devices can propagate simultaneously through the common optics and can spatially overlap (but not completely overlap) onto the switching engine. The switching engine can be configured to exclusively redirect light associated with the first input / output device to a plurality of first outputs and to exclusively redirect light associated with the second input / output device to a plurality of second outputs.

[0017] In some implementations, the controller can provide different operating modes, during which each input is configured with a different wavelength band. For example, during a first operating mode, the first input can be configured to provide C-band light, and the second input can be configured to provide L-band light. During a second operating mode, the first input can be configured to provide L-band light, and the second input can be configured to provide C-band light. The controller can split the band between the two inputs at any point because each input can support continuous C and L spectra. Therefore, the controller can limit the type of light allowed in each input fiber such that the wavelength of each input fiber does not overlap with the wavelengths of different input fibers.

[0018] By splitting the input and output, C+L band WSS devices can have twice the output port count of single-band devices, making lateral offset negligible for common optics, and dedicating a wavelength band to each input / output pair, thus eliminating competition between the two systems. Therefore, doubling the output can be achieved without using a band splitter.

[0019] In some implementations, C+L band WSS devices are designed as dual WSS devices. Therefore, a C+L band WSS device may include a third input / output device (e.g., a third integrated C and L device) and a fourth input / output device (e.g., a fourth integrated C and L device) integrated into a single WSS device, having shared or common second optics for beam shaping, wavelength dispersion, and for output steering or switching light for both the third and fourth input / output devices. The controller may operate the third and fourth input / output devices in a manner similar to that described for the first and second input / output devices, such that there is no wavelength competition between the third and fourth input / output devices. The optical design may image the input pair onto the same portion of the switching engine, having the option to operate as competing integrated C and L bands. The device can then operate as a C+L dual WSS by limiting functions via the controller.

[0020] In some implementations, C+L band dual WSS devices are provided using a four-row fiber array input (e.g., a 4×40 array). In some examples, a C+L band dual WSS device can be a C+L band 2×78 dual WSS device. Instead of imaging four separate sections onto the LCOS, each C / L input pair of a C+L band 2×78 dual WSS device is imaged onto the same portion of the switching engine. Typically, there is wavelength competition between C / L input pairs imaged onto the same section, but this is no longer a factor if the port is used as a dedicated C or L port. By using dedicated C or L ports in a C+L band 2×78 dual WSS device, the size and cost of the WSS can be reduced compared to a true (conventional) 2×78 WSS device. Furthermore, the steering angle (range) only requires accommodating 39 ports instead of 78 ports. A C+L band dual WSS device is equivalent to a conventional C-band WSS + L-band WSS. C+L band dual WSS devices can be used as high port count (HPC) integrated C and L WSSs. Furthermore, compared to conventional C-band WSS+L-band WSSs, C+L band dual WSS devices allow for limited or reduced module height for high port counts. C+L band dual WSS devices enable lower (e.g., smaller) steering angles for port selection. Additionally, C+L band dual WSS devices can reduce end-of-life (EOL) sensitivity requirements for HPC WSSs.

[0021] The WSS described herein can include competitive four-channel integrated C and L modules with limited ports in the optical system. The ports of the WSS can be bundled for either C-band or L-band to eliminate competition and operate as a dual-line device. The WSS can redefine the meaning of integrated C and L. Since amplifiers and transceivers are currently bundled, there is no use case for truly integrated C and L WSS devices. Because the WSS is designed as a band C+L device, it can accommodate both C-band and L-band in a single WSS device, which is equivalent to separate C-band and L-band WSS devices.

[0022] In some implementations, the C+L band dual WSS device includes a four-row fiber array, with the four rows being C-port (module 1), L-port (module 1), C-port (module 2), and L-port (module 2). Both C-port (module 1) and L-port (module 1) are coupled to the upper half of the switching engine. However, due to lateral offset in the four-row fiber array, there is a lateral offset (frequency offset) in the corresponding image on the switching engine. Both C-port (module 2) and L-port (module 2) are coupled to the lower half of the switching engine. This frequency offset prevents signals originating from the C-port from unintentionally coupling into the L-port.

[0023] In some implementations, the C+L band dual WSS device includes a two-row fiber array, the first row of which has a C-port (module 1) and an L-port (module 1), and the second row of which has a C-port (module 2) and an L-port (module 2). Both the C-port (module 1) and L-port (module 1) are coupled to the upper half of the switching engine, and because there is no lateral offset in the two-row fiber array, there is no frequency offset. Specifically, the C-port and L-port of module 1 can operate as a grouped dual WSS, where each group of ports transmits wavelengths from both the C-band and L-band, and the switching engine simultaneously controls the wavelength and port configuration of both WSSs (e.g., the two WSSs will be configured identically). However, the use of such a grouped dual WSS is not known to date, and there may be potential crosstalk between the C-port and L-port. Both the C-port (module 2) and L-port (module 2) are coupled to the lower half of the switching engine.

[0024] In some implementations, the C+L band dual WSS device includes two rows of fiber arrays. The first row of the two fiber arrays has a C-port (module 1) and an L-port (module 2), and the second row of the two fiber arrays has an L-port (module 1) and a C-port (module 2). The Module 1 port is coupled to the upper half of the switching engine, and the Module 2 port is coupled to the lower half of the switching engine. Module 1 will have a positive frequency offset between the C-port and L-port (a positive frequency gap between the C-channel and L-channel on the switching engine), and Module 2 will have a negative frequency offset between the C-port and L-port (a negative frequency gap, or overlapping of the C-channel and L-channel on the switching engine). This can work if the negative frequency offset is less than the channel gap of the communication network between the C-band and L-band.

[0025] In some implementations, the C+L band dual WSS device includes two rows of fiber arrays, the first row of which has a C port (module 1) and a C port (module 2), and the second row of which has an L port (module 1) and an L port (module 2). The module 1 port is coupled to the upper half of the switching engine, and the module 2 port is coupled to the lower half of the switching engine.

[0026] In some implementations, the C+L band dual WSS device includes a single-row fiber array (e.g., a single-row fiber array) in which the C and L ports of module 1 and module 2 are both in a single row. The port of module 1 is coupled to the upper half of the switching engine, and the port of module 2 is coupled to the lower half of the switching engine. This configuration has the advantage of using a single-row fiber array, which is easier to manufacture than a multi-row (two-dimensional (2D)) fiber array, but suffers from the disadvantages of long fiber arrays and potential crosstalk between the C and L ports.

[0027] Figure 1A WSS 100 according to one or more embodiments is illustrated. The WSS 100 may include a first input 102a, a second input 102b, a plurality of first outputs 104a dedicated to the first input 102a, a plurality of second outputs 104b dedicated to the second input 102b, and a common optics 106. The common optics 106 may be configured such that the plurality of first outputs 104a are configured to receive light originating from the first input 102a, but not to receive light from the second input 102b. Therefore, the common optics 106 may be configured such that the plurality of second outputs 104b are configured to receive light originating from the second input 102b, but not to receive light from the first input 102a. For example, the first input 102a and the second input 102b may be spatially offset from each other such that the light from the first input 102a and the light from the second input 102b partially (but not completely) overlap spatially with the spatial offset. Based on spatial offset, the common optics 106 is designed to guide light from the first input 102a at one or more of the plurality of first outputs 104a, and to avoid guiding light to any of the plurality of second outputs 104b. Therefore, based on spatial offset, the common optics 106 is designed to guide light from the second input 102b at one or more of the plurality of second outputs 104b, and to avoid guiding light to any of the plurality of first outputs 104a.

[0028] The first input 102a and the plurality of first outputs 104a may be part of a first input / output device. The second input 102b and the plurality of second outputs 104b may be part of a second input / output device. In some embodiments, the first input / output device may be part of or may include a first fiber optic array unit, which includes a first input fiber optic 108a and a plurality of first output fibers 110a. The first input fiber 108a may be coupled to the first input 102a, and the plurality of first output fibers 110a may be correspondingly coupled to the plurality of first outputs 104a. The second input / output device may be part of or may include a second fiber optic array unit, which includes a second input fiber optic 108b and a plurality of second output fibers 110b. The second input fiber 108b may be coupled to the second input 102b, and the plurality of second output fibers 110b may be correspondingly coupled to the plurality of second outputs 104b.

[0029] The first input / output device and the second input / output device can share a common optics 106, which can be used for beam shaping, wavelength dispersion, and output steering or switching of light for both the first input / output device and the second input / output device. The common optics 106 may include a switching engine for steering the corresponding light of both input / output devices. Therefore, the first input 102a and the second input 102b can be configured to emit corresponding light into the common optics 106. Additionally, a plurality of first outputs 104a and a plurality of second outputs 104b can receive corresponding light from the common optics 106.

[0030] The first input 102a and the first input optical fiber 108a can support a first wavelength band (such as the C-band) and a second wavelength band (such as the L-band). In other words, the first input 102a and the first input optical fiber 108a can be naturally designed for both C-band and L-band light. Therefore, the first input 102a and the first input optical fiber 108a can support the full C+L band spectrum. The second input 102b and the second input optical fiber 108b can support both the first and second wavelength bands. In other words, the second input 102b and the second input optical fiber 108b can be naturally designed for both C-band and L-band light. Therefore, the second input 102b and the second input optical fiber 108b can support the full C+L band spectrum.

[0031] In some cases, the controller (not shown) can be configured to have different wavelength bands for the first input 102a and the second input 102b to ensure no wavelength competition between the first input / output device and the second input / output device. Light associated with the first input / output device and light associated with the second input / output device can propagate simultaneously through a common optics 106 and can spatially overlap (but not completely overlap) onto the switching engine of the common optics 106. The switching engine can be configured to exclusively redirect light associated with the first input / output device (e.g., light associated with the first input 102a) to a plurality of first outputs 104a, and to exclusively redirect light associated with the second input / output device (e.g., light associated with the second input 102b) to a plurality of second outputs 104b.

[0032] In some implementations, the controller can provide different operating modes during which each input is configured with a different wavelength band. For example, during a first operating mode, the first input 102a can be configured to provide C-band light, and the second input 102b can be configured to provide L-band light. During a second operating mode, the first input 102a can be configured to provide L-band light, and the second input 102b can be configured to provide C-band light. Therefore, the controller can limit the type of light allowed in each of the input fibers 108a, 108b, such that the wavelength of a particular input fiber does not overlap with the wavelengths of different input fibers.

[0033] In some embodiments, the first input fiber 108a may be configured to provide a first beam including a first plurality of wavelength channels in a first wavelength band. Additionally, the second input fiber 108b may be configured to provide a second beam including a second plurality of wavelength channels in a second wavelength band. In some embodiments, the first and second beams may be simultaneously emitted into the WSS 100 (e.g., into a common optics 106), such that both the first and second beams propagate through the common optics 106. The first and second wavelength bands may be mutually exclusive wavelength bands to avoid wavelength competition within the common optics 106. In other words, the first and second wavelength bands do not overlap. Therefore, the first input 102a can provide a first beam in the first wavelength band, and the second input 102b can provide a second beam in the second wavelength band.

[0034] The first input fiber 108a and the second input fiber 108b can be arranged such that the first beam and the second beam partially overlap in space with spatial offset. For example, in the absence of wavelength competition, the first beam and the second beam partially overlap within a common optics 106. The controller can confine the first beam to a first wavelength band and the second beam to a second wavelength band during a first operating mode, such that there is no wavelength competition between the first beam and the second beam. In other words, the first beam may have a first wavelength component exclusively within the first wavelength band, and the second beam may have a second wavelength component exclusively within a second wavelength band that does not overlap with the first wavelength band. Therefore, the first beam does not include wavelength components outside the first wavelength band, and the second beam does not include wavelength components outside the second wavelength band.

[0035] In some embodiments, the first input fiber 108a and / or the first input 102a are configured to provide a third beam including a third plurality of wavelength channels in the second wavelength band, and the second input fiber 108b and / or the second input 102b are configured to provide a fourth beam including a fourth plurality of wavelength channels in the first wavelength band. The controller can limit the third beam to the second wavelength band and the fourth beam to the first wavelength band during a second operating mode, such that there is no wavelength competition between the third and fourth beams.

[0036] The WSS 100 can operate without a band splitter. In other words, the configuration of confining the first and second beams to different wavelength bands during operation and having a dedicated output for each input allows the WSS 100 to be designed without a band splitter. This reduces the manufacturing cost, size, and complexity of the WSS 100 compared to conventional WSS devices. Additionally, this configuration doubles the number of output ports within a single WSS device. Furthermore, since inputs 102a and 102b are naturally designed for the full C+L spectrum, the controller can tune the wavelength band of each input / output device to anywhere within the full C+L spectrum, provided that the wavelength bands propagating through the common optics 106 do not overlap.

[0037] The WSS 100 can be designed as a dual WSS with one of the dual configurations described herein (e.g., a band iXCL dual WSS or a band C+L dual WSS device). For example, it can be replicated. Figure 1 The configuration shown. Figure 1The configuration shown can be used as a first module (module 1), and a replicated configuration can be used as a second module (module 2) within the WSS device, thereby forming a dual WSS device. The second module may include a third input / output device (e.g., a third iCL device) and a fourth input / output device (e.g., a fourth iCL device), having shared or common second optics for beam shaping, wavelength dispersion, and for output steering or switching of light for both the third and fourth input / output devices. The common optics of the first module may be separate from the common optics of the second module. In some embodiments, the first and second modules may share the same common optics, including the same switching engine, provided that the light from the first module remains spatially separated from the light from the second module. In some embodiments, light from the first and third input / output devices may be limited by a controller to a first wavelength band or to a second wavelength band, and light from the second and fourth input / output devices may be limited by a controller to wavelength bands not used by the first and third input / output devices. In some implementations, light from the first input / output device, the second input / output device, the third input / output device, and the fourth input / output device can be limited by the controller to different, non-overlapping wavelength bands.

[0038] As indicated above, provide Figure 1 As an example. Other examples may differ from those regarding... Figure 1 The example described.

[0039] Figure 2 A WSS 200 according to one or more embodiments is illustrated. The WSS 200 may include a first input / output device 200a (such as a first fiber array unit) and a second input / output device 200b (such as a second fiber array unit), similar to a combination of... Figure 1 The described components. WSS 200 may include common optics, including a microcollimating lens array 204, a beam-shaping optics 206, a first imaging element 208, a wavelength dispersive element 210, a second imaging element 212, and / or a switching engine 214. The common optics may be combined with... Figure 1 The described common optical device 106 corresponds to this.

[0040] The beam-shaping optics 206 can receive a first beam and a second beam from the microcollimating lens array 204 as spatially overlapping beams. The beam-shaping optics 206 can shape or further adjust the first and second beams such that they are incident on the wavelength dispersive element 210 and / or the switching engine 214 with desired shapes, angles, and / or magnifications. For example, the beam-shaping optics 206 can shape the first and second beams into narrow beams. The beam-shaping optics 206 can be optically coupled to the first imaging element 208. Therefore, the beam-shaping optics 206 can receive the first and second beams from the first input / output device 200a and the second input / output device 200b, respectively, shape them into narrow beams, and guide the narrow beams toward the first imaging element 208. In some embodiments, the beam-shaping optics 206 may include a combination of a first beam-shaping component 206a and a second beam-shaping component 206b for shaping and adjusting light.

[0041] The first imaging element 208 can image the first beam and the second beam onto the wavelength dispersive element 210 at an infinite conjugate plane.

[0042] The wavelength dispersive element 210 can disperse a first plurality of wavelength channels of a first beam into a first sub-beam group according to wavelength, and can disperse a second plurality of wavelength channels of a second beam into a second sub-beam group according to wavelength. In other words, the wavelength dispersive element 210 can separate the first beam into one or more first sub-beams according to wavelength, and separate the second beam into one or more second sub-beams according to wavelength. The wavelength dispersive element 210 may include components positioned to separate the beam into sub-beam groups (e.g., having different wavelengths) for transmission toward the switching engine in the forward propagation direction, and / or reconstituted light sub-beams for transmission toward the first input / output device 200a and the second input / output device 200b in the reverse propagation direction, which is opposite to the forward propagation direction. For example, the wavelength dispersive element 210 may include a prism, a diffraction grating, etc. For example, the wavelength dispersive element 210 is... Figure 2 The reflection diffraction grating is used in some embodiments. A reflecting prism (e.g., a composite optical element consisting of a grating and one or more prisms) can be used as a reflection diffraction grating. Compared to other types of wavelength dispersive elements, reflection diffraction gratings enable more compact designs and reduce losses.

[0043] The second imaging element 212 can image the first sub-beam group and the second sub-beam group onto the switching engine 214 at the focal plane. In some embodiments, the first imaging element 208 can be a collimating element configured to image the first beam and the second beam onto the wavelength dispersive element 210. The second imaging element 212 can be a focusing element configured to image the first sub-beam group (e.g., one or more first sub-beams) and the second sub-beam group (e.g., one or more second sub-beams) onto the switching engine 214. The first imaging element 208 and the second imaging element 212 can perform different optical functions depending on the direction of light propagation. For example, the first imaging element 208 can be a first collimating element in the forward propagation direction and a first focusing element in the reverse propagation direction. The second imaging element 212 can be a second focusing element in the forward propagation direction and a second collimating element in the reverse propagation direction. In some embodiments, the first imaging element 208 and the second imaging element 212 can be part of a telescopic optics 216.

[0044] The switching engine 214 can redirect a first sub-beam group in a first wavelength selective manner to couple the first sub-beam group to one or more first output fibers among a plurality of first output fibers. In other words, the switching engine 214 can redirect the sub-beam according to the wavelength of each sub-beam. Additionally, the switching engine 214 can redirect a second sub-beam group in a second wavelength selective manner to couple the second sub-beam group to one or more second output fibers among a plurality of second output fibers. Therefore, the switching engine 214 can individually redirect each sub-beam in the first sub-beam group to couple each sub-beam in the first sub-beam group to a corresponding first output fiber among a plurality of first output fibers of the first input / output device 202a. Furthermore, the switching engine 214 can individually redirect each sub-beam in the second sub-beam group to couple each sub-beam in the second sub-beam group to a corresponding second output fiber among a plurality of second output fibers of the second input / output device 202b.

[0045] The switching engine 214 can redirect the first and second sub-beam groups to propagate back to the first input / output device 202a and the second input / output device 202b via the second imaging element 212, the wavelength dispersive element 210, and the first imaging element 208, respectively. In other words, the switching engine 214 can redirect the first and second sub-beam groups to propagate back through the common optics in the reverse propagation direction. The first sub-beam group can be spatially offset from the second sub-beam group at the switching engine 214. This spatial offset at the switching engine 214 allows the switching engine 214 to proprietaryly redirect the first sub-beam group back to the first input / output device 202a and proprietaryly redirect the second sub-beam group back to the second input / output device 202b.

[0046] The switching engine 214 (sometimes referred to as a switching element, modification element, or beam shaping device) may include components capable of modifying and / or redirecting a beam (e.g., the beam provided by the wavelength dispersive element 210) such that the beam can be switched between output fibers associated with the WSS 200. For example, the switching engine 214 may include a microelectromechanical system (MEMS) array comprising a movable micromirror array, an LCOS phase modulator array, a liquid crystal polarization rotation element, and a birefringent beam steering element, etc. The switching engine 214 may proprietaryly deflect a sub-beam originating from the first input / output device 202a in the output of the first input / output device 202a, and may proprietaryly deflect a sub-beam originating from the second input / output device 202b in the output of the second input / output device 202b. Therefore, the switching engine 214 can independently redirect each sub-beam in the first sub-beam group to couple the first sub-beam group to one or more of a plurality of first outputs dedicated to a first input, and the switching engine 214 can independently redirect each sub-beam in the second sub-beam group to couple the second sub-beam group to one or more of a plurality of second outputs dedicated to a second input.

[0047] Controller 218 can control the output direction of switching engine 214. For example, controller 218 can control how switching engine 214 modulates or directs each sub-beam (e.g., each wavelength channel or wavelength component). Controller 218 can control which output receives light and which wavelength the output receives. Controller 218 can control the reflection angle or steering angle of the sub-beams redirected by switching engine 214. Therefore, controller 218 can select from a plurality of first outputs which output switching engine 214 will direct a sub-beam from a first sub-beam group to. Similarly, controller 218 can select from a plurality of second outputs which output switching engine 214 will direct a sub-beam from a second sub-beam group to.

[0048] In some implementations, controller 218 can configure a first input of the first input / output device 202a and a second input of the second input / output device 202b to have different wavelength bands to ensure no wavelength competition between the first input / output device 202a and the second input / output device 202b (e.g., no wavelength competition between the first beam and the second beam). For example, controller 218 can provide different operating modes during which each input is configured with a different wavelength band. For example, during a first operating mode, the first input can be configured to provide C-band light, and the second input can be configured to provide L-band light. During a second operating mode, the first input can be configured to provide L-band light, and the second input can be configured to provide C-band light. Therefore, the controller can limit the type of light allowed in each input fiber such that the wavelength of a particular input fiber does not overlap with the wavelengths of different input fibers.

[0049] During a first operating mode, a first beam may include a first plurality of wavelength channels in a first wavelength band, and a second beam may include a second plurality of wavelength channels in a second wavelength band. Controller 218 may limit the first beam to the first wavelength band and the second beam to the second wavelength band, such that there is no wavelength competition between the first and second beams. During a second operating mode, a first input / output device 202a may provide a third beam, and a second input / output device 202b may provide a fourth beam. The third beam may include a third plurality of wavelength channels in the second wavelength band, and the fourth beam may include a fourth plurality of wavelength channels in the first wavelength band. Controller 218 may limit the third beam to the second wavelength band and the fourth beam to the first wavelength band, such that there is no wavelength competition between the third and fourth beams.

[0050] WSS 200 can be designed as a dual WSS (e.g., a C+L band dual WSS) with one of the dual configurations described herein.

[0051] As indicated above, provide Figure 2 As an example. Other examples may differ from those regarding... Figure 2 The example described. Figure 2 The number and arrangement of the devices and components shown are provided as examples. In practice, there may be... Figure 2 Compared to the equipment or component shown, there are additional equipment or components, fewer equipment or components, different equipment or components, or equipment or components with different arrangements.

[0052] Figure 3 This is a flowchart of an example process 300 associated with C-band and L-band WSSs having high output port counts. In some implementations, Figure 3One or more process blocks are executed by C-band and L-band WSSs (e.g., WSS 100 and WSS 200). In some implementations, Figure 3 One or more process blocks are executed by another device or a group of devices that are separate from or include the C and L band WSS. Additionally or alternatively, Figure 3 One or more process blocks in the process block can be executed by one or more components in the C and L band WSS.

[0053] like Figure 3 As shown, process 300 may include: transmitting a first light beam into the WSS, the first light beam having a first wavelength component proprietary in a first wavelength band (block 310). For example, a first input to the WSS may transmit the first light beam into the WSS as described above.

[0054] like Figure 3 It is also shown that process 300 may include emitting a second beam into the WSS, the second beam having a second wavelength component proprietary in a second wavelength band that does not overlap with the first wavelength band (box 320). For example, a second input to the WSS may emit the second beam into the WSS as described above.

[0055] like Figure 3 It is also shown that process 300 may include: imaging the first beam and the second beam onto a wavelength dispersive element at an infinite conjugate plane (box 330). For example, the first imaging element of the WSS may image the first beam and the second beam onto the wavelength dispersive element at an infinite conjugate plane, as described above.

[0056] like Figure 3 It is also shown that process 300 may include separating the first wavelength component into a first sub-beam group (block 340). For example, the wavelength dispersive element of the WSS can separate the first wavelength component into the first sub-beam group, as described above.

[0057] like Figure 3 It is also shown that process 300 may include separating the second wavelength component into a second sub-beam group (block 350). For example, the wavelength dispersive element of the WSS can separate the second wavelength component into a second sub-beam group, as described above.

[0058] like Figure 3 It is also shown that process 300 may include: imaging the first sub-beam group and the second sub-beam group onto the switching engine at the focal plane (box 360). For example, the second imaging element of the WSS may image the first sub-beam group and the second sub-beam group onto the switching engine at the focal plane, as described above.

[0059] like Figure 3It is also shown that process 300 may include: independently redirecting each sub-beam in the first sub-beam group to couple the first sub-beam group to one or more of a plurality of first outputs, wherein the plurality of first outputs are dedicated to the first input (box 370). For example, the switching engine of the WSS may independently redirect each sub-beam in the first sub-beam group to couple the first sub-beam group to one or more of a plurality of first outputs, as described above.

[0060] like Figure 3 It is also shown that process 300 may include: independently redirecting each sub-beam in the second sub-beam group to couple the second sub-beam group to one or more of a plurality of second outputs, wherein the plurality of second outputs are dedicated to the second input (box 380). For example, the switching engine of the WSS may independently redirect each sub-beam in the second sub-beam group to couple the second sub-beam group to one or more of a plurality of second outputs, as described above.

[0061] Process 300 may include additional implementations, such as any single implementation or any combination of implementations, such as those described below and / or those combined with one or more other processes described elsewhere herein.

[0062] In the first embodiment, the first beam and the second beam are simultaneously emitted into the WSS.

[0063] In the second embodiment, the first beam is conventional wavelength band (C-band) light, and the second beam is long wavelength band (L-band) light.

[0064] although Figure 3 An example block diagram of process 300 is shown. In some embodiments, process 300 includes... Figure 3 The boxes depicted in the process 300 may be additional boxes, fewer boxes, different boxes, or boxes with different arrangements compared to the additional boxes depicted in the process 300. Alternatively or additionally, two or more boxes in the process 300 may be executed in parallel.

[0065] The following provides an overview of some aspects of this disclosure:

[0066] Aspect 1: A wavelength selective switch, comprising: a switching engine configured to redirect light; a wavelength dispersive element optically coupled bidirectionally to the switching engine; a first fiber array unit including a first input fiber and a plurality of first output fibers, wherein the first input fiber is capable of supporting a first wavelength band and a second wavelength band, wherein the first input fiber is configured to provide a first beam including a first plurality of wavelength channels in the first wavelength band; a second fiber array unit including a second input fiber and a plurality of second output fibers, wherein the second input fiber is capable of supporting the first wavelength band and the second wavelength band, wherein the second input fiber is configured to provide a second beam including a second plurality of wavelength channels in the second wavelength band, wherein the first wavelength band and the second wavelength band are mutually exclusive wavelength bands, wherein the first input fiber and the second input fiber are arranged such that the first beam and the second beam are partially spatially offset. The system comprises: a first imaging element configured to image a first beam and a second beam onto a wavelength dispersive element at an infinite conjugate plane, wherein the wavelength dispersive element is configured to disperse a first plurality of wavelength channels into a first sub-beam group and disperse a second plurality of wavelength channels into a second sub-beam group; and a second imaging element configured to image the first sub-beam group and the second sub-beam group onto a switching engine at a focal plane, wherein the switching engine is configured to redirect the first sub-beam group in a first wavelength selective manner to couple the first sub-beam group to one or more of a plurality of first output fibers, and wherein the switching engine is configured to redirect the second sub-beam group in a second wavelength selective manner to couple the second sub-beam group to one or more of a plurality of second output fibers; and a controller configured to, during a first operating mode, confine the first beam to a first wavelength band and the second beam to a second wavelength band.

[0067] Aspect 2: The wavelength selective switch according to Aspect 1, wherein the first input fiber is configured to provide a third beam including a third plurality of wavelength channels in a second wavelength band, wherein the second input fiber is configured to provide a fourth beam including a fourth plurality of wavelength channels in a first wavelength band, and wherein the controller is configured to restrict the third beam to the second wavelength band and the fourth beam to the first wavelength band during a second operating mode.

[0068] Aspect 3: A wavelength selective switch according to any one of Aspects 1-2, wherein the switching engine is configured to individually redirect each sub-beam in a first sub-beam group to couple each sub-beam in the first sub-beam group to a corresponding first output fiber in a plurality of first output fibers, and wherein the switching engine is configured to individually redirect each sub-beam in a second sub-beam group to couple each sub-beam in the second sub-beam group to a corresponding second output fiber in a plurality of second output fibers.

[0069] Aspect 4: A wavelength selection switch according to any one of aspects 1-3, wherein the switching engine is configured to redirect the first sub-beam group and the second sub-beam group to propagate back to the first fiber array unit and the second fiber array unit via the second imaging element, the wavelength dispersive element and the first imaging element, respectively.

[0070] Aspect 5: A wavelength selection switch according to any one of aspects 1-4, wherein the wavelength dispersive element is a reflection diffraction grating.

[0071] Aspect 6: The wavelength selection switch according to any one of aspects 1-5 further includes: an optical component comprising a first imaging element and a second imaging element.

[0072] Aspect 7: A wavelength selective switch according to any one of aspects 1-6, wherein the first imaging element is a first collimating element in the forward propagation direction and a first focusing element in the reverse propagation direction, and wherein the second imaging element is a second focusing element in the forward propagation direction and a second collimating element in the reverse propagation direction.

[0073] Aspect 8: The wavelength selection switch according to any one of aspects 1-7 further includes: a beam shaping optics optically coupled to a first imaging element, wherein the beam shaping optics is configured to: receive a first beam and a second beam from a first fiber array unit and a second fiber array unit, respectively, shape the first beam and the second beam into narrow beams, and guide the narrow beams toward the first imaging element.

[0074] Aspect 9: A wavelength selection switch according to any one of Aspects 1-8, wherein the first wavelength band is the first band of a conventional wavelength band (C-band) or a long wavelength band (L-band), and wherein the second wavelength band is the second band of a C-band or an L-band.

[0075] Aspect 10: A wavelength selective switch according to any one of Aspects 1-9, wherein the switching engine is a liquid crystal on silicon (LCOS) array or a micromirror array of microelectromechanical systems (MEMS).

[0076] Aspect 11: A wavelength selection switch according to any one of aspects 1-10, wherein the first sub-beam group is spatially offset from the second sub-beam group at the switching engine.

[0077] Aspect 12: A wavelength selective switch comprising: a first input configured to provide a first beam in a first wavelength band; a plurality of first outputs dedicated to the first input; a second input spatially offset from the first input, wherein the second input is configured to provide a second beam in a second wavelength band, the second wavelength band not overlapping with the first wavelength band; a plurality of second outputs dedicated to the second input; a wavelength dispersive element configured to receive the first beam, receive the second beam, separate the first beam into one or more first sub-beams, and separate the second beam into one or more second sub-beams; and a beam steering device configured to: redirect one or more first sub-beams in a first wavelength selective manner to couple one or more first sub-beams to one or more first outputs of a plurality of first outputs, and redirect one or more second sub-beams in a second wavelength selective manner to couple one or more second sub-beams to one or more second outputs of a plurality of second outputs.

[0078] Aspect 13: The wavelength selection switch according to aspect 12, wherein the beam steering device is configured to individually redirect each of one or more first sub-beams to couple each of one or more first sub-beams to a corresponding first output of a plurality of first outputs, and wherein the beam steering device is configured to individually redirect each of one or more second sub-beams to couple each of one or more second sub-beams to a corresponding second output of a plurality of second outputs.

[0079] Aspect 14: A wavelength selective switch according to any one of aspects 12-13, wherein a first input and a second input are configured to simultaneously provide a first beam and a second beam, such that the first beam and the second beam overlap in the intrinsic space of the wavelength selective switch with spatial offset.

[0080] Aspect 15: The wavelength selection switch according to any one of aspects 12-14 further includes: a collimation element configured to image a first beam and a second beam onto a wavelength dispersive element; and a focusing element configured to image one or more first sub-beams and one or more second sub-beams onto a beam steering device.

[0081] Aspect 16: The wavelength selection switch according to aspect 15, wherein the focusing element is configured to image one or more first sub-beams and one or more second sub-beams onto the beam steering device in the presence of spatial offset.

[0082] Aspect 17: The wavelength selection switch according to aspect 15, wherein the beam steering device is configured to redirect one or more first sub-beams and one or more second sub-beams to propagate back to a plurality of first outputs and a plurality of second outputs via a focusing element, a wavelength dispersive element, and a collimating element, respectively.

[0083] Aspect 18: A wavelength selection switch according to any one of Aspects 12-17, wherein the first wavelength band is the first band of a conventional wavelength band (C-band) or a long wavelength band (L-band), and wherein the second wavelength band is the second band of a C-band or an L-band.

[0084] Aspect 19: A wavelength selective switch according to any one of aspects 12-18, wherein the wavelength dispersive element is a diffraction grating.

[0085] Aspect 20: A method comprising: transmitting a first beam from a first input to a wavelength selective switch, the first beam having a first wavelength component specifically in a first wavelength band; transmitting a second beam from a second input to the wavelength selective switch, the second beam having a second wavelength component specifically in a second wavelength band not overlapping with the first wavelength band; imaging the first beam and the second beam onto a wavelength dispersive element at an infinite conjugate plane by a first imaging element; separating the first wavelength component into a first sub-beam group by the wavelength dispersive element; separating the second wavelength component into a second sub-beam group by the wavelength dispersive element; imaging the first sub-beam group and the second sub-beam group onto a switching engine at a focal plane by a second imaging element; independently redirecting each sub-beam in the first sub-beam group by the switching engine to couple the first sub-beam group to one or more of a plurality of first outputs, wherein the plurality of first outputs are dedicated to the first input; and independently redirecting each sub-beam in the second sub-beam group by the switching engine to couple the second sub-beam group to one or more of a plurality of second outputs, wherein the plurality of second outputs are dedicated to the second input.

[0086] Aspect 21: According to the method of aspect 20, the first beam and the second beam are simultaneously emitted into a wavelength selective switch.

[0087] Aspect 22: The method according to any one of Aspects 20-21, wherein the first beam is conventional wavelength band (C-band) light, and wherein the second beam is long wavelength band (L-band) light.

[0088] Aspect 23: A system configured to perform one or more operations described in one or more of aspects 1-22.

[0089] Aspect 24: An apparatus comprising one or more operating means for performing one or more of the aspects described in aspects 1-22.

[0090] Aspect 25: A non-transitory computer-readable medium storing an instruction set comprising, when executed by a device, causing the device to perform one or more operations described in one or more of aspects 1-22.

[0091] Aspect 26: A computer program product comprising instructions or code for performing one or more operations described in one or more of aspects 1-22.

[0092] The foregoing disclosure provides illustrations and descriptions, but is not intended to be exhaustive or to limit implementations to the precise forms disclosed. Modifications and variations may be made in light of the foregoing disclosure or derived from practice of implementation. Furthermore, any implementation described herein can be combined unless the foregoing disclosure explicitly provides for reasons why one or more implementations may not be combined.

[0093] Even if specific combinations of features are listed in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of the various implementations. In fact, many of these features can be combined in ways not specifically listed in the claims and / or disclosed in the specification. Although each dependent claim listed below may depend directly on only one claim, the disclosure of the various implementations includes every dependent claim combined with every other claim in the claim set. As used herein, the phrase “at least one of…” in the reference list of items refers to any combination of these items, including a single member. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination having multiple identical items.

[0094] When a component or a component of one or more components (e.g., a laser emitter or one or more laser emitters) is described or claimed (within a single claim or over multiple claims) to perform or be configured to perform multiple operations, this language is intended to broadly cover a wide range of architectures and environments. For example, unless explicitly claimed otherwise (e.g., by using “first component” and “second component” or other language distinguishing components in the claims), this language is intended to cover a single component performing or configured to perform all operations, a group of components jointly performing or configured to perform all operations, a first component performing or configured to perform a first operation and a second component performing or configured to perform a second operation, or any combination of components performing or configured to perform these operations. For example, when a claim takes the form “one or more components are configured to: perform X; perform Y; and perform Z,” the claim should be interpreted as meaning “one or more components are configured to perform X; one or more (possibly different) components are configured to perform Y; and one or more (possibly different) components are configured to perform Z.”

[0095] Unless explicitly stated otherwise, the elements, actions, or instructions used herein should not be construed as critical or necessary. Furthermore, as used herein, the articles “a” and “one” are intended to include one or more items and may be used interchangeably with “one or more.” Further, as used herein, the article “the” is intended to include one or more items referenced in conjunction with the article “the” and may be used interchangeably with “one or more.” Additionally, as used herein, the term “set” is intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items) and may be used interchangeably with “one or more.” In cases referring to only one item, the phrase “only one” or similar language is used. Furthermore, as used herein, the terms “has,” “have,” “having,” etc., are intended as open-ended terms. Further, unless explicitly stated otherwise, the phrase “based on” is intended to mean “at least partially based on.” Moreover, as used herein, unless explicitly stated otherwise (e.g., if used in combination with “any one” or “only one of…”), the term “or” when used in series is intended to be inclusive and may be used interchangeably with “and / or.” Furthermore, spatial relative terms (such as “below,” “lower,” “above,” “upper,” etc.) may be used herein for ease of description to describe the relationship of an element or feature to another element or feature(s) illustrated in the accompanying drawings. In addition to the orientations depicted in the accompanying drawings, spatial relative terms are intended to cover different orientations of apparatus, devices, and / or elements in use or operation. The apparatus may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein may be interpreted accordingly.

Claims

1. A wavelength selective switch, comprising: The engine was switched and configured to redirect the light. Wavelength dispersive elements are optically coupled bidirectionally to the switching engine; The first fiber array unit includes a first input fiber and multiple first output fibers. The first input optical fiber can support both a first wavelength band and a second wavelength band. The first input optical fiber is configured to provide a first beam, the first beam including a first plurality of wavelength channels in a first wavelength band; The second fiber array unit includes a second input fiber and multiple second output fibers. The second input optical fiber can support both the first wavelength band and the second wavelength band. The second input optical fiber is configured to provide a second beam, which includes a second plurality of wavelength channels in a second wavelength band. The first wavelength band and the second wavelength band are mutually exclusive wavelength bands. The first input fiber and the second input fiber are arranged such that the first beam and the second beam partially overlap in space with spatial offset. A first imaging element is configured to image the first beam and the second beam onto the wavelength dispersive element at an infinite conjugate plane. The wavelength dispersive element is configured to disperse the first plurality of wavelength channels into a first sub-beam group and the second plurality of wavelength channels into a second sub-beam group; as well as The second imaging element is configured to image the first sub-beam group and the second sub-beam group onto the switching engine at the focal plane. The switching engine is configured to redirect the first sub-beam group in a first wavelength-selective manner to couple the first sub-beam group to one or more of the plurality of first output fibers, and The switching engine is configured to redirect the second sub-beam group in a second wavelength-selective manner to couple the second sub-beam group to one or more of the plurality of second output fibers; as well as The controller is configured to, during a first operating mode, limit the first beam to the first wavelength band and the second beam to the second wavelength band.

2. The wavelength selective switch of claim 1, wherein the first input optical fiber is configured to provide a third beam, the third beam comprising a third plurality of wavelength channels in the second wavelength band. The second input fiber is configured to provide a fourth beam, which includes a fourth plurality of wavelength channels in the first wavelength band, and The controller is configured to limit the third beam to the second wavelength band and the fourth beam to the first wavelength band during the second operating mode.

3. The wavelength selective switch of claim 1, wherein the switching engine is configured to individually redirect each sub-beam in the first sub-beam group to couple each sub-beam in the first sub-beam group to a corresponding first output fiber in the plurality of first output fibers, and The switching engine is configured to individually redirect each sub-beam in the second sub-beam group to couple each sub-beam in the second sub-beam group to a corresponding second output fiber in the plurality of second output fibers.

4. The wavelength selective switch of claim 1, wherein the switching engine is configured to redirect the first sub-beam group and the second sub-beam group to propagate back to the first fiber array unit and the second fiber array unit, respectively, via the second imaging element, the wavelength dispersive element, and the first imaging element.

5. The wavelength selective switch according to claim 1, wherein the wavelength dispersive element is a reflection diffraction grating.

6. The wavelength selective switch according to claim 1, further comprising: Optical components, including the first imaging element and the second imaging element.

7. The wavelength selective switch according to claim 1, wherein the first imaging element is a first collimating element in the forward propagation direction and a first focusing element in the reverse propagation direction, and The second imaging element is a second focusing element in the forward propagation direction and a second collimating element in the reverse propagation direction.

8. The wavelength selective switch according to claim 1, further comprising: A beam-shaping optics device is optically coupled to the first imaging element, wherein the beam-shaping optics device is configured to receive the first beam and the second beam from the first fiber array unit and the second fiber array unit, respectively, shape the first beam and the second beam into narrow beams, and guide the narrow beams toward the first imaging element.

9. The wavelength selective switch according to claim 1, wherein the first wavelength band is the first band among the conventional wavelength band C-band or the long wavelength band L-band, and The second wavelength band is the second band in either the C band or the L band.

10. The wavelength selective switch according to claim 1, wherein the switching engine is a silicon-based liquid crystal LCOS array or a microelectromechanical system (MEMS) micromirror array.

11. The wavelength selective switch of claim 1, wherein the first sub-beam group is spatially offset from the second sub-beam group at the switching engine.

12. A wavelength selective switch, comprising: The first input is configured to provide a first beam in a first wavelength band; Multiple first outputs, dedicated to the first input; The second input is spatially offset from the first input, wherein the second input is configured to provide a second beam in a second wavelength band that does not overlap with the first wavelength band; Multiple second outputs, dedicated to the second input; A wavelength dispersive element is configured to receive the first light beam, receive the second light beam, separate the first light beam into one or more first sub-beams, and separate the second light beam into one or more second sub-beams; and The beam steering device is configured as follows: Using a first wavelength selection method, the one or more first sub-beams are redirected to couple the one or more first sub-beams to one or more of the plurality of first outputs, and The one or more second sub-beams are redirected in a second wavelength selection manner to couple the one or more second sub-beams to one or more of the plurality of second outputs.

13. The wavelength selective switch of claim 12, wherein the beam steering device is configured to individually redirect each of the one or more first sub-beams to couple each of the one or more first sub-beams to a corresponding first output of the plurality of first outputs, and The beam steering device is configured to individually redirect each of the one or more second sub-beams to couple each of the one or more second sub-beams to a corresponding second output of the plurality of second outputs.

14. The wavelength selective switch of claim 12, wherein the first input and the second input are configured to simultaneously provide the first beam and the second beam, such that the first beam and the second beam overlap in the intrinsic space of the wavelength selective switch with spatial offset.

15. The wavelength selective switch according to claim 12, further comprising: A collimating element is configured to image the first beam and the second beam onto the wavelength dispersive element; as well as A focusing element is configured to image the one or more first sub-beams and the one or more second sub-beams onto the beam steering device.

16. The wavelength selective switch of claim 15, wherein the focusing element is configured to image the one or more first sub-beams and the one or more second sub-beams onto the beam steering device in the presence of spatial offset.

17. The wavelength selective switch of claim 15, wherein the beam steering device is configured to redirect the one or more first sub-beams and the one or more second sub-beams to propagate back to the plurality of first outputs and the plurality of second outputs, respectively, via the focusing element, the wavelength dispersive element, and the collimating element.

18. The wavelength selective switch according to claim 12, wherein the first wavelength band is the first band of the conventional wavelength band C-band or the long wavelength band L-band, and The second wavelength band is the second band in either the C band or the L band.

19. The wavelength selective switch according to claim 12, wherein the wavelength dispersive element is a diffraction grating.

20. A method comprising: A first beam is emitted from a first input to a wavelength selection switch, the first beam having a first wavelength component exclusive to a first wavelength band; A second beam is emitted from a second input into the wavelength selection switch, the second beam having a second wavelength component that is exclusive to a second wavelength band that does not overlap with the first wavelength band; The first imaging element images the first beam and the second beam onto the wavelength dispersive element at an infinite conjugate plane; The wavelength dispersive element separates the first wavelength component into a first sub-beam group; The wavelength dispersive element separates the second wavelength component into a second sub-beam group; The second imaging element images the first beam group and the second beam group onto the switching engine at the focal plane; Each sub-beam in the first sub-beam group is independently redirected by the switching engine to couple the first sub-beam group to one or more of a plurality of first outputs, wherein the plurality of first outputs are dedicated to the first input; as well as Each sub-beam in the second sub-beam group is independently redirected by the switching engine to couple the second sub-beam group to one or more of a plurality of second outputs, wherein the plurality of second outputs are dedicated to the second input.

21. The method of claim 20, wherein the first beam and the second beam are simultaneously emitted into the wavelength selection switch.

22. The method of claim 20, wherein the first beam is conventional wavelength band C-band light, and The second beam is a long-wavelength L-band light.

Images