Optical device for generating overlapping polarized beams for liquid crystal on silicon (LCOS) beam steering

Abstract

Embodiments of the present disclosure relate to optical devices that generate overlapping polarized beams for liquid crystal on silicon (LCOS) beam steering. An optical system includes a beam steering device configured with a beam steering dependency dependent on a first polarization, and an optical arrangement including an input, first and second optical paths, and an output. The first optical path and the second optical path extend from the input end and intersect at the same incident point on the beam steering device. The optical device is configured to split an input beam into two orthogonally polarized beams, direct the first polarized beam along a first optical path, and direct the second polarized beam along a second optical path. The optical arrangement is configured to provide the first polarized beam and the second polarized beam to the beam steering device as spatially overlapping beams having the same polarization. The beam steering device is configured to steer the first polarized beam and the second polarized beam toward the output end in a common output direction.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to U.S. Provisional Patent Application No. 63 / 601,387, filed on November 21, 2023, and entitled “PRISM ARRANGEMENT GENERATING OVERLAPPING POLARIZATION BEAMS FOR LCOS BEAM STEERING.” The disclosure of the prior application is considered a part of and incorporated by reference into this patent application. Technical Field

[0003] The present disclosure generally relates to polarization-dependent beam steering. Background Art

[0004] Wavelength Selective Switches (WSS) are widely used for dynamic routing of wavelength channels in optical communication networks. WSS devices can be deployed in optical switching nodes in long-distance, regional, and metropolitan optical communication networks.

[0005] The long wavelength band and the regular band range are commonly referred to as the L-band and C-band, respectively. There is a growing demand in the industry for wide band (C+L-band) and high port count WSS devices. These WSS devices need to allow for flexible selection of optical channel widths to be directed to the output. Setting the channel width of the channel and the beam steering of the channel are typically done by a liquid crystal on silicon (LCOS) chip. LCOS is a miniaturized reflective active matrix liquid crystal display or "microdisplay" that uses a liquid crystal layer on top of a silicon backplane. LCOS may also be referred to as a spatial light modulator or director array. LCOS-based beam steering typically requires that the incident beam have a single polarization orientation that is aligned with the LCOS operating direction. Summary of the invention

[0006] In some implementations, an optical system includes a beam steering device configured with a beam steering dependency that depends on a first polarization, wherein the beam steering device is configured to steer only light having the first polarization; and an optical device including an input end, a first optical path and a second optical path, and an output end, wherein the input end is configured to receive an input beam having an arbitrary polarization state, and wherein the first optical path and the second optical path extend from the input end and intersect at a same incident point on the beam steering device, wherein the optical device further includes: a first optical component configured to split the input beam into two orthogonal polarization beams including a first polarization beam and a second polarization beam, wherein the first optical component is configured to direct the input beam along the first optical path. The invention relates to an optical component for guiding a first polarized beam with a first polarization along a light path, and guiding a second polarized beam with a second polarization orthogonal to the first polarization along a second light path; and a second optical component configured to receive the second polarized beam, rotate the second polarization of the second polarized beam to the first polarization, and further guide the second polarized beam with the first polarization along the second light path, wherein the first optical component and the second optical component are configured such that the first polarized beam with the first polarization and the second polarized beam with the first polarization spatially overlap at a beam steering device, and wherein the beam steering device is configured to steer the first polarized beam and the second polarized beam toward an output end, so that the first polarized beam and the second polarized beam are guided from the output end in a common output direction.

[0007] In some embodiments, an optical system includes a beam steering device, which is configured with a beam steering dependency that depends on linear polarization, wherein the beam steering device is configured to steer only light with linear polarization; and an optical device, which includes an input end, a first optical path and a second optical path, and an output end, wherein the input end is configured to receive an input light beam with an arbitrary polarization state, and wherein the first optical path and the second optical path extend from the input end and intersect at the same incident point on the beam steering device, wherein the optical device also includes: a polarization grating arranged at the input end and the output end, wherein the polarization grating is configured to split the input beam into two orthogonal polarized beams including a first polarized beam with left circular polarization and a second polarized beam with right circular polarization, including a first extended optical path. A first reflector including a delay device, wherein the first reflector is arranged on a first optical path between a polarization grating and a beam steering device, wherein the first reflector is configured to convert left circular polarization of the first polarized beam into linear polarization, and further guide the first polarized beam with linear polarization along the first optical path; and a second reflector including a second delay device, wherein the second reflector is arranged on a second optical path between a polarization grating and the beam steering device, wherein the second reflector is configured to convert right circular polarization of the second polarized beam into linear polarization, and further guide the second polarized beam with linear polarization along the second optical path, wherein the beam steering device is configured to steer the first polarized beam and the second polarized beam toward an output end, so that the first polarized beam and the second polarized beam are guided from the output end in a common output direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figures 1A to 1D An optical system is shown in accordance with one or more implementations.

[0009] Figure 2 An optical system is shown in accordance with one or more implementations.

[0010] Figure 3 An optical system is shown in accordance with one or more implementations.

[0011] FIG. 4A to FIG. 4C An optical system is shown in accordance with one or more implementations.

[0012] Figure 5A and Figure 5B Input / output direction arrangements are shown according to one or more implementations.

[0013] Figure 6 Input / output direction arrangements are shown according to one or more implementations. DETAILED DESCRIPTION

[0014] The following detailed description of example implementations refers to the accompanying drawings.The same reference numbers in different drawings may identify the same or similar elements.

[0015] In a WSS device, polarization is typically selected in the front-end optics of the WSS device (e.g., near the input fiber / output fiber). This is accomplished by first splitting the input beam into two orthogonal polarizations, and second, rotating one of the polarizations so that both beams have the same polarization. These beams are relayed to the LCOS through other optical components of the WSS device.

[0016] The WSS device may have a wavelength dispersion direction and a port switching direction perpendicular to the wavelength dispersion direction. In the case where the input beam is split in the wavelength dispersion direction of the WSS device, two beams are incident on the apertures of the grating, which reduces the resolution by a factor of two compared to not splitting the input beam into two polarizations. If the input beam is split in the port switching direction of the WSS device, the number of ports that can be fitted into the apertures of the grating is reduced by a factor of two.

[0017] Polarization-independent LCOS designs eliminate the requirement to split the input beam into two polarizations, thus allowing high port counts and high resolution. Unfortunately, polarization-independent LCOS are difficult to manufacture. Therefore, an alternative approach that can work with polarization-dependent LCOS designs has significant advantages.

[0018] Some polarization-dependent optical devices have additional disadvantages. For example, some polarization-dependent optical devices split the incident light into two beams (e.g., two polarizations), and the two beams have different propagation times. The different propagation times result in differential group delay (DGD), also known as polarization mode dispersion (PMD). DGD is not suitable for processing beams with high bit rate modulation. In another example, the incident light can be split into two beams (e.g., two polarizations). However, due to the different number of reflections between the two beams, the two beams need to be controlled by the LCOS in opposite directions in order to reappear from the WSS device with the same propagation direction. This may occur, for example, when the difference in the number of reflections is an odd number. By writing different beam steering patterns into two different regions or sections of the LCOS, the two beams can be steered in opposite directions. Therefore, the two beams need to be spatially separated from each other on the LCOS, for example, without spatial overlap. A disadvantage of this approach is that space is required on the LCOS to accommodate the two spatially separated beams, which means that the size of each beam must be half the size when only one beam is used. This in turn doubles the steering angle per port and reduces the total number of ports that can be handled with a given steering angle range.

[0019] Some implementations described herein provide a WSS device configured to intersect a first beam and a second beam at the same point on an LCOS. In other words, the first beam and the second beam substantially overlap on the LCOS, and in some cases completely overlap. Thus, the beam size of each beam can be as large as the entire LCOS (e.g., as large as the aperture of the LCOS), thereby minimizing the steering angle of each port and maximizing the total number of ports in the WSS device. Thus, the WSS device can avoid limiting the total port count. In addition, the intersection angle can be in the beam steering direction (e.g., the port switching direction) so that the spectral resolution can be optimized.

[0020] Some implementations provide an optical system that can generate overlapping polarized beams for LCOS beam steering. The optical system can be disposed in a WSS for port steering. The optical system can be configured to split an incident unpolarized beam into two polarized beams (e.g., a first polarized beam and a second polarized beam) having orthogonal polarizations, rotate the first polarized beam to have the same polarization state as the second polarized beam; intersect the two polarized beams at the same area on the LCOS with an intersection angle in a beam steering direction; have equal focal lengths within a tolerance of the two polarized beams; and have the same number of reflections in each beam path of the two polarized beams so that the LCOS can steer the two polarized beams in the same direction. Alternatively, the difference between the number of reflections of the two beam paths can be a multiple of 2 so that the LCOS can steer the two polarized beams in the same direction.

[0021] "Focal length" is defined as (approximately, for elements with flat surfaces) the material thickness divided by the sum of the refractive indices. "Optical path length" is defined as the material thickness multiplied by the sum of the refractive indices. The focal points of the two polarized beams can be made to lie in the plane of the LCOS even though the physical length of each path may be different. Similarly, different refractive indices can be used to maintain the same optical path length for the two polarized beams. Therefore, by making different parts of the optical system out of materials with different refractive indices, the focal lengths of the two polarized beams can be made equal within a tolerance, and the optical path lengths of the two polarized beams can be made equal within a tolerance.

[0022] Figures 1A to 1D An optical system 100 is shown according to one or more implementations. The optical system 100 can be implemented in a WSS device, for example for port steering. The y-axis can correspond to the wavelength dispersion direction, and the z-axis can correspond to the port switching direction. The optical system 100 can include a beam steering device 102 and an optical arrangement 104.

[0023] The beam steering device 102 can be configured with a beam steering dependency that depends on polarization (such as P polarization or S polarization). For example, the beam steering device 102 can be configured to steer only light having a first polarization (e.g., P polarization). In some implementations, the beam steering device 102 can be a polarization-dependent LCOS array, a polarization-dependent spatial light modulator, or a polarization-dependent light guide array. The beam steering device 102 can be configured to steer two polarized light beams to a common output direction. However, in order to steer two polarized light beams simultaneously, the two polarized light beams incident on the beam steering device 102 must have the same polarization orientation as the polarization on which the beam steering device 102 operates. Therefore, if the beam steering device 102 is configured to steer light having a first polarization, the two polarized light beams must have the first polarization at the beam steering device 102.

[0024] The optical device 104 may include a plurality of optical components configured to direct two polarized light beams along respective optical paths. The optical device 104 may include an input end 106 (e.g., an optical input end), an output end 108 (e.g., an optical output end), a first optical path 110 for the first polarized beam, a second optical path 112 for the second polarized beam, a third optical path 114 for the first polarized beam, and a fourth optical path 116 for the second polarized beam. Figure 1A Trajectories of a first polarized beam, a first reflected polarized beam, a second polarized beam, and a second reflected polarized beam with actual beam widths are shown. The first polarized beam and the second polarized beam substantially overlap at the beam steering device 102, if not completely overlap. Figure 1B Trajectories of a first polarized beam, a first reflected polarized beam, a second polarized beam, and a second reflected polarized beam with corresponding polarizations are shown. The first reflected polarized beam is generated by reflecting the first polarized beam at the beam steering device 102. The second reflected polarized beam is generated by reflecting the second polarized beam at the beam steering device 102. Figure 1C Trajectories of a first polarized beam on a first optical path 110 and a first reflected polarized beam on a third optical path 114 are shown. Figure 1D The trajectories of the second polarized beam on the second optical path 112 and the second reflected polarized beam on the fourth optical path 116 are shown.

[0025] The input end 106 can receive an input beam having any polarization state (e.g., a non-polarized state). Thus, the input beam can include a P-polarization component and an S-polarization component (e.g., a first polarized beam and a second polarized beam). The first optical path 110 and the second optical path 112 can extend from the input end 106 and intersect at the same incident point on the beam steering device 102. For example, after reflection at the beam steering device 102, the third optical path 114 and the fourth optical path 116 can extend from the beam steering device 102 to the output end 108.

[0026] The optical device 104 may include a first optical component 118 and a second optical component 120. The first optical component 118 may split the input beam into two orthogonal polarized beams (e.g., two orthogonal linear polarizations) including a first polarized beam and a second polarized beam. The first optical component 118 may direct the first polarized beam along a first optical path with a first polarization (such as a P polarization). In addition, the first optical component 118 may direct the second polarized beam along a second optical path with a second polarization (such as an S polarization) orthogonal to the first polarization. In some implementations, the first optical component 118 may be a polarization beam splitter (PBS) disposed on the first optical path 110 and the second optical path 112.

[0027] The second optical component 120 can receive the second polarized beam, rotate the second polarization of the second polarized beam to the first polarization, and further guide the second polarized beam with the first polarization along the second optical path 112. In other words, the second optical component 120 can convert the second polarization of the second polarized beam to the first polarization so that both the first polarized beam and the second polarized beam have the same polarization (e.g., the first polarization or the P polarization) at the beam steering device 102. In some implementations, the second optical component 120 can convert the second polarization of the second polarized beam to the first polarization by a 90-degree rotation of the second polarization. In some implementations, the second optical component 120 can be a quarter wave retarder (QWR) or a half wave retarder (HWR). In some implementations, the quarter wave retarder can be a quarter wave plate (QWP). In some implementations, the half wave retarder can be a half wave plate (HWP).

[0028] In addition, the first optical component 118 and the second optical component 120 are configured to spatially overlap the first polarization beam having the first polarization and the second polarization beam having the first polarization at the beam steering device 102. The beam steering device 102 can steer the first polarization beam and the second polarization beam toward the output end 108 so that the first polarization beam and the second polarization beam are directed from the output end 108 in a common output direction. In other words, the beam steering device 102 can simultaneously receive and steer both the first polarization beam and the second polarization beam so that the first polarization beam and the second polarization beam are ultimately combined by the optical device 104 into a combined output beam, which is output from the output end 108 in a common output direction. The common output direction may depend on the beam steering angle of the beam steering device 102. When the optical device 104 is implemented in a WSS device, the optical device 104 may include an additional optical component configured to calibrate the first polarization beam and the second polarization beam in a port switching direction and focus the first polarization beam and the second polarization beam in a wavelength dispersion direction.

[0029] In some implementations, the first optical component 118 and the second optical component 120 can be configured such that the first polarized beam having the first polarization and the second polarized beam having the first polarization spatially overlap at the beam steering device 102. For example, at least 90% of a first region of the beam steering device 102 where the first polarized beam is incident on the beam steering device 102 spatially overlaps with a second region of the beam steering device 102 where the second polarized beam is incident on the beam steering device. In some implementations, the first optical component 118 and the second optical component 120 can be configured such that the first polarized beam having the first polarization and the second polarized beam having the first polarization completely spatially overlap at the beam steering device 102. The first polarized beam and the second polarized beam can fill or substantially fill an aperture of the beam steering device 102. In other words, a beam size of the first polarized beam and a beam size of the second polarized beam can be as large as an entire aperture size of the beam steering device 102.

[0030] In addition, the first optical component 118 and the second optical component 120 can be configured so that the first polarized beam having the first polarization and the second polarized beam having the first polarization intersect at the same incident point at an intersection angle in the beam steering direction of the beam steering device 102. For example, when the first polarized beam and the second polarized beam intersect at the beam steering device 102, they can be parallel to Figure 1A in the xz plane.

[0031] In some implementations, the optical device 104 can have equal or substantially equal focal lengths for the first polarized beam and the second polarized beam (e.g., within a tolerance). For example, the optical device 104 can focus the first polarized beam onto the beam steering device 102 in a wavelength dispersion direction within a first focal depth, and the optical device 104 can focus the second polarized beam onto the beam steering device 102 in a wavelength dispersion direction within a second focal depth. As a result, the focal lengths of the two polarized beams can be made equal within a tolerance so that both the first polarized beam and the second polarized beam are focused at the beam steering device 102. In some implementations, the first focal depth can be equal to or substantially equal to the second focal depth. Additionally or alternatively, a first optical path length of the first polarized beam from the input end 106 to the output end 108 can be equal to or substantially equal to a second optical path length of the second polarized beam from the input end 106 to the output end 108.

[0032] Furthermore, the optical device 104 can be configured such that the first optical path 110 has a first number of reflections, and the second optical path 112 has a second number of reflections equal to the first number of reflections. Alternatively, the difference between the first number of reflections and the second number of reflections can be a multiple of 2. As a result, the first polarized beam and the second polarized beam can spatially overlap at the beam steering device 102, and both the first polarized beam and the second polarized beam can be provided by the optical device 104 to the output end 108 in a common output direction.

[0033] In some implementations, the beam steering device 102 can be configured to reflect a first polarized beam such that the first polarized beam is folded back into the second optical path 112, and to reflect a second polarized beam such that the second polarized beam is folded back into the first optical path 110. For example, when the beam steering device 102 is not performing active beam steering (e.g., during zero-order reflection), the first polarized beam can be folded back into the second optical path when reflected by the beam steering device 102, and the second polarized beam can be folded back into the first optical path 110 when reflected by the beam steering device 102. Reflection orders can be referred to as diffraction orders. "Zero-order reflection" (e.g., zero-order diffraction) can refer to the reflection of a non-diffracted beam by the beam steering device 102. In other words, when no grating is displayed or written on the beam steering device 102 (e.g., on an LCOS array), the zero-order reflection can represent a beam path. In contrast, during active steering by the beam steering device 102, first-order reflections (e.g., first-order diffraction) can occur. A "first-order reflection" may refer to a reflection of a diffracted beam by the beam steering device 102. In other words, when a grating is displayed or written on the beam steering device 102 (e.g., on an LCOS array), a first-order reflection may represent a controlled beam path. Higher-order reflections or negative-order reflections may occur when a grating is displayed or written on the beam steering device 102 and there is diffracted light in an undesired direction (e.g., at an undesired diffraction angle). Thus, a positive first-order reflection may represent a desired or expected reflection in the intended beam steering direction (e.g., at a desired diffraction angle), while a negative first-order reflection or second-order reflection may represent an undesired or undesired reflection.

[0034] Alternatively, the optical device 104 can be configured to guide the combined output beam of the zero-order reflection to have a different position and angle than the input beam. For a WSS device, it may be necessary to avoid back reflections to the input end. Therefore, when the beam steering device 102 is used to attenuate the input beam with a zero-order reflection, the zero-order reflection direction is the direction in which the attenuated light is guided. Therefore, it may be desirable that the light from the zero-order reflection is not coupled into any output port of the WSS device to avoid port crosstalk. In some cases, the zero-order reflection direction may be aligned with the input end, and in other cases, the zero-order reflection direction may be offset from the input end. In other words, based on the application, the input direction or angle of the input beam and the common output direction or angle of the combined output beam may be the same or different.

[0035] In some implementations, the beam steering device 102 can reflect the first polarized beam as a first reflected polarized beam on the third optical path 114 toward the second optical component 120. The second optical component 120 can receive the first reflected polarized beam, rotate the first polarization of the first reflected polarized beam to a second polarization, and direct the first reflected polarized beam with the second polarization toward the first optical component 118. In other words, the second optical component 120 can convert the first polarization of the first reflected polarized beam to the second polarization. In addition, the beam steering device 102 can reflect the second polarized beam as a second reflected polarized beam on the fourth optical path 116 toward the first optical component 118.

[0036] The first optical component 118 may direct the first reflected polarized beam having the second polarization toward the output end 108 by reflection. In addition, the first optical component 118 may cause the second reflected polarized beam to pass toward the output end 108 with the first polarization. In other words, after the first reflected polarized beam interacts with the second optical component 120, the first reflected polarized beam and the second reflected polarized beam may have orthogonal polarizations. The first reflected polarized beam and the second reflected polarized beam may be combined at the output end 108 with orthogonal polarizations, and may be output from the output end 108 in a common output direction that depends on the beam steering angle of the beam steering device 102. In some implementations, the first optical component 118 may combine the first reflected polarized beam with the second reflected polarized beam into a combined output beam, and direct the combined output beam at the output end 108 in the common output direction. Therefore, the optical device 104 may be configured to combine the first reflected polarized beam and the second reflected polarized beam having orthogonal polarizations into a combined output beam, and output the combined output beam at the output end 108. The position of the combined output beam relative to the input beam may correspond to the optical path length of the optics 104 and the beam steering angle of the beam steering device. For example, the longer the optical path length, the greater the separation between the output 108 and the input 106 in the z-direction.

[0037] In some implementations, the sum of the first optical path 110 and the third optical path 114, which represent the first total optical path from the input end 106 to the output end 108, has a first total optical path length. In addition, the sum of the second optical path 112 and the fourth optical path 116, which represent the second total optical path from the input end 106 to the output end 108, has a second total optical path length. The optical device 104 can be configured such that the first total optical path length and the second total optical path length are equal or substantially equal. For example, for data transmitted through the WSS device, the first total optical path length and the second total optical path length can be substantially equal within 1 / 10 of a bit period.

[0038] The optical device 104 may include a first prism 122 and a second prism 124, and the second prism 124 is optically coupled between the first prism 122 and the beam steering device 102. The first prism 122 may include an input end 106, an output end 108, a first optical component 118, a second optical component 120, and a first reflector 126. The second prism 124 may include a second reflector 128 and a third reflector 130. In this example, the first optical component 118 may be a PBS disposed on the first optical path 110, the second optical path 112, the third optical path 114, and the fourth optical path 116. In addition, the second optical component 120 may be a quarter-wave retarder having a 45-degree optical axis orientation. The first reflector 126 may be a mirror disposed on the surface of the first prism 122, a reflective surface coupled to the surface, or a reflective film integrated with the surface. In addition, the second reflector 128 and the third reflector 130 may be mirrors disposed on the respective surfaces of the second prism 124, reflective surfaces coupled to the surfaces, or reflective films integrated with the surfaces.

[0039] An input beam having an arbitrary polarization state may be provided at the input end 106 of the first prism 122. The first optical component 118 generates a first polarized beam and a second polarized beam having orthogonal linear polarization states. The first polarized beam having the first polarization transmits through the first optical component 118 and is guided along the first optical path to the beam steering device 102 via reflections at the second reflector 128 and the third reflector 130 (e.g., via reflection B1 and reflection B2, respectively). The second polarized beam is reflected by the first optical component 118 (e.g., via reflection A1) towards the second optical component 120. The second polarized beam transmits through the second optical component 120 and is reflected back by the first reflector 126 through the second optical component 120 (e.g., via reflection A2). Therefore, the second polarized beam passes through the second optical component 120 twice, causing a 90-degree polarization rotation.

[0040] After being reflected by the first reflector 126 and passing through the second optical component 120 for the second time, the second polarized beam exhibits the same polarization state as the first polarized beam. The first reflector 126 may be oriented such that the second polarized beam is directed towards the beam steering device 102. Therefore, the first polarized beam and the second polarized beam are directed towards the beam steering device 102 such that the first polarized beam and the second polarized beam intersect at the same incident point on the beam steering device 102 in a manner that the first polarized beam and the second polarized beam have the same polarization spatial overlap at the beam steering device 102. In this example, both the first optical path 110 and the second optical path 112 include two reflections.

[0041] In some implementations, the first optical component 118 may extend along the entire edge length of the surface of the first prism 122 that contacts the second prism 124.

[0042] In some implementations, the material used for the first prism 122 and the second prism 124 can be the same, so that the first prism 122 has the same refractive index as the second prism 24. In some implementations, the first prism 122 can have a higher refractive index than the refractive index of the second prism 124 so as to reduce the size of the first prism 122. For example, the height of the first prism 122 can be reduced by using a lower refractive index than the refractive index of the second prism 124, while maintaining the same optical path length of the two polarized beams (e.g., the first optical path length of the first polarized beam from the input end to the output end is equal to or substantially equal to the second optical path length of the second polarized beam from the input end to the output end). Therefore, the refractive index can be adjusted to reduce the size of the prism arrangement while maintaining equal or substantially equal optical path lengths and / or focal lengths, as described above. Under these conditions, a WSS device with optimized port count, spectral resolution, and PMD can be achieved. In some implementations, larger beam sizes and higher port counts may be used compared to WSS devices that require spatial separation of the two polarized beams at the beam steering device.

[0043] In some implementations, the optical system 100 is a WSS, which includes multiple input directions corresponding to multiple input ports, respectively, and multiple output directions corresponding to multiple output ports, respectively. The beam steering device 102 can reflect the first polarized beam as a first reflected polarized beam on a third optical path 114 toward the output end 108 with a first zero-order reflection (e.g., zero-order diffraction). In addition, the beam steering device 102 can reflect the second polarized beam as a second reflected polarized beam on a fourth optical path 116 toward the output end 108 with a second zero-order reflection. During the zero-order diffraction, the optical device 104 can provide an angular offset between the first optical path 110 and the second optical path 112 at the beam steering device 102, so that the first reflected polarized beam and the second reflected polarized beam are output in a common output direction directed away from all multiple output ports. For example, the common output direction can be directed outside the range of the multiple output directions. Alternatively, the common output direction can point between two adjacent output directions in the multiple output directions. The reflective sides of the first prism 122 and the second prism 124 may be oriented in a manner that defines an angular offset between the first optical path 110 and the second optical path 112 .

[0044] Furthermore, during active beam steering, the beam steering device 102 may reflect the first polarized beam as a first reflected polarized beam on a third optical path 114 toward the output end 108 with a first positive first-order reflection (e.g., positive first-order diffraction), and reflect the second polarized beam as a second reflected polarized beam on a fourth optical path 116 toward the output end 108 with a second positive first-order reflection. However, unlike during zero-order diffraction, the optical device 104 may provide an angular offset between the first optical path 110 and the second optical path 112 at the beam steering device 102, such that the first reflected polarized beam and the second reflected polarized beam are output in a common output direction that points only to a configured output port selected from a plurality of output ports. In other words, the angular offset may be configured to ensure that the common output direction does not point to any unexpected or undesired output port (e.g., at any unconfigured output port) in order to avoid crosstalk between the output ports. The reflective sides of the first prism 122 and the second prism 124 may be oriented in a manner that defines an angular offset between the first optical path 110 and the second optical path 112 .

[0045] In addition, during active beam steering, the beam steering device 102 can reflect the first polarized beam as a third reflected polarized beam reflected toward the output end 108 on the fifth optical path with a first negative first-order reflection (e.g., negative first-order diffraction), and reflect the second polarized beam as a fourth reflected polarized beam on the sixth optical path toward the output end 108 with a second negative first-order reflection. The third reflected polarized beam and the fourth reflected polarized beam can be interference signals generated by negative first-order diffraction. The fifth optical path and the sixth optical path can be different from the third optical path and the fourth optical path. The optical device 104 can provide an angular offset between the first optical path and the second optical path at the beam steering device 102, so that the third reflected polarized beam and the fourth reflected polarized beam are output in one or more directions directed away from all of the multiple output ports. In other words, the angular offset can be configured to ensure that the third reflected polarized beam and the fourth reflected polarized beam do not point to any output port so as to avoid crosstalk between the output ports. The reflective sides of the first prism 122 and the second prism 124 may be oriented in a manner that defines an angular offset between the first optical path 110 and the second optical path 112 .

[0046] In addition, during active beam steering, the beam steering device 102 can reflect the first polarized beam as a fifth reflected polarized beam on the seventh optical path toward the output end 108 with a first second-order reflection (e.g., second-order diffraction), and reflect the second polarized beam as a sixth reflected polarized beam on the eighth optical path toward the output end 108 with a second second-order reflection. The fifth reflected polarized beam and the sixth reflected polarized beam can be interference signals generated by the second-order diffraction. The seventh optical path and the eighth optical path can be different from the third optical path, the fourth optical path, the fifth optical path, and the sixth optical path. The optical device 104 can provide an angular offset between the first optical path and the second optical path at the beam steering device 102, so that the fifth reflected polarized beam and the sixth reflected polarized beam are output in one or more directions directed away from all of the multiple output ports. In other words, the angular offset can be configured to ensure that the fifth reflected polarized beam and the sixth reflected polarized beam are not directed to any output port so as to avoid crosstalk between the output ports. The reflective sides of the first prism 122 and the second prism 124 may be oriented in a manner that defines an angular offset between the first optical path 110 and the second optical path 112 .

[0047] As indicated above, Figures 1A to 1D Provided as an example. Other examples may be about Figures 1A to 1D Described differently. Figures 1A to 1D The number and arrangement of devices and components shown are provided as examples. In practice, there may be additional devices or components, fewer devices or components, different devices or components, or different Figures 1A to 1D Devices or components are shown arranged differently.

[0048] Figure 2 An optical system 200 is shown according to one or more implementations. The optical system 200 can be implemented in a WSS device, for example, for port steering. Figures 1A to 1D Similar to the described optical system 100 , this optical system includes a beam steering device 202 and an optical arrangement 204 .

[0049] The beam steering device 202 may be configured with a beam steering dependency that depends on polarization, such as P polarization or S polarization. The optical device 204 may include a plurality of optical components configured to direct two polarized light beams along respective optical paths. The optical device 204 may include an input end 106, an output end 108, a first optical path 110 for a first polarized beam, a second optical path 112 for a second polarized beam, a third optical path 114 for the first polarized beam, and a fourth optical path 116 for the second polarized beam, as combined Figures 1A to 1D Similar to what is described.

[0050] In addition, the optical device 204 can generate overlapping polarized beams for beam steering. The optical device 204 can be configured to split an input beam with an arbitrary polarization state into two polarized beams (e.g., a first polarized beam and a second polarized beam) with orthogonal polarizations; rotate the first polarized beam to have the same polarization state as the second polarized beam; make the two polarized beams intersect at the same area on the beam steering device 202, with an intersection angle in the beam steering direction; have equal focal lengths within the tolerance of the two polarized beams; and have the same number of reflections in each optical path of the two polarized beams, so that the beam steering device 202 can steer the two polarized beams in the same direction. Alternatively, the difference between the number of reflections of the two beam paths can be a multiple of 2, so that the beam steering device 302 can control the two polarized beams in the same direction. In addition, different refractive indices can be used to maintain the same focal length of the two polarized beams. Therefore, by making different parts of the optical system made of materials with different refractive indices, the focal lengths of the two polarized beams can be equal or substantially equal. For example, the optical device 204 can focus the first polarized beam on the beam steering device 202 in the wavelength dispersion direction within the first focal depth, and the optical device 204 can focus the second polarized beam on the beam steering device 202 in the wavelength dispersion direction within the second focal depth. As a result, the focal lengths of the two polarized beams can be made equal within a tolerance so that both the first polarized beam and the second polarized beam are focused at the beam steering device 202. In addition, the total optical path lengths from the input end to the output end of the two polarized beams can be made equal or substantially equal. For example, for data transmitted through the WSS device, the first total optical path length and the second total optical path length can be substantially equal within 1 / 10 of the bit period. The common output direction of the two polarized beams depends on the beam steering angle of the beam steering device 202. Therefore, the position of the combined output beam relative to the input beam corresponds to the optical path length of the optical device 204 and the beam steering angle of the beam steering device 202. For example, the longer the optical path length, the greater the separation between the output end 108 and the input end 106 in the z direction.

[0051] The optical device 204 may include a first optical component 118 (e.g., a PBS) and a second optical component 120 (e.g., a half-wave retarder). In this example, the first polarized beam is reflected by the first optical component 118, and the second polarized beam is transmitted through the first optical component 18. The second polarized beam may be transmitted through the second optical component 120, and the second optical component 120 may rotate the polarization of the second polarized beam to match the polarization of the first polarized beam. The first optical component and the second optical component are configured so that the first polarized beam and the second polarized beam have the same polarization at the beam steering device 202.

[0052] The optical device 204 may include a first prism 206, a second prism 208 having a reflector 210, an optical component 211 made of a high refractive index material for maintaining equal focal lengths in the two optical paths, a first redirecting prism 212, and a second redirecting prism 214. The first prism 206 may include an input end 106, an output end 108, and a first optical component 118 disposed on the first optical path 110 and the second optical path 112. The second prism 208 may be disposed on the second optical path 112 and optically coupled between the first prism 206 and the second optical component 120. The reflector 210 disposed on the second optical path 112 may be configured to redirect the second polarized beam further along the second optical path 112 toward the second optical component 120 and the beam steering device 202. The second optical component 120 can be a half-wave retarder (HWR) disposed between the optical component 211 and the second redirecting prism 214, as shown, disposed between the first prism 206 and the second prism 208, or disposed between the second prism 206 and the optical component 211. Alternatively, the second optical component 120 can be a half-wave retarder disposed between the first prism 206 and the first redirecting prism 212. Alternatively, the second optical component 120 can be a quarter-wave retarder (QWR) disposed at the reflector 210.

[0053] The first redirection prism 212 can be arranged on the first optical path 110 and optically coupled between the first prism 206 and the beam steering device 202. The first redirection prism 212 can direct the first polarized beam at the beam steering device 202. The second redirection prism 214 arranged on the second optical path 112 can be optically coupled between the second prism 208 and the beam steering device 202. The second redirection prism 214 can direct the second polarized beam having the same polarization as the first polarized beam at the beam steering device 202. The optical device 204 can be configured so that the first polarized beam and the second polarized beam spatially overlap at the beam steering device 202 with the same polarization state. The beam steering device 202 can steer the first polarized beam and the second polarized beam toward the output end 108 so that the first polarized beam and the second polarized beam are directed from the output end 108 in a common output direction.

[0054] In some implementations, the beam steering device 202 can be configured to reflect the first polarized beam as a first reflected polarized beam on the third optical path 114 toward the second optical component 120. The second optical component 120 can receive the first reflected polarized beam, rotate the polarization of the first reflected polarized beam by 90 degrees, and direct the first reflected polarized beam toward the reflector 210, which can direct the first reflected polarized beam toward the first optical component 118 with the rotated polarization. Additionally, the beam steering device 202 can reflect the second polarized beam as a second reflected polarized beam on the fourth optical path 116 toward the first optical component 118.

[0055] The first optical component 118 can direct the second reflected polarized beam toward the output end 108 via reflection. In addition, the first optical component 118 can cause the first reflected polarized beam to pass toward the output end 108 with a polarization that is orthogonal to the polarization of the second reflected polarized beam. The first reflected polarized beam and the second reflected polarized beam can be combined at the output end 108 with orthogonal polarizations and can be output from the output end 108 in a common output direction that depends on the beam steering angle of the beam steering device 202. In some implementations, the first optical component 118 can combine the first reflected polarized beam with the second reflected polarized beam into a combined output beam and direct the combined output beam toward the output end 108 in the common output direction.

[0056] In some implementations, the sum of the first optical path 110 and the third optical path 114, which represent a first total optical path from the input end 106 to the output end 108, has a first total optical path length. Additionally, the sum of the second optical path 112 and the fourth optical path 116, which represent a second total optical path from the input end 106 to the output end 108, has a second total optical path length. The optical device 204 can be configured such that the first total optical path length and the second total optical path length are equal or substantially equal.

[0057] As indicated above, Figure 2 Other examples may be provided as examples. Figure 2 Described differently. Figure 2 The number and arrangement of devices and components shown are provided as examples. In practice, there may be additional devices or components, fewer devices or components, different devices or components, or different Figure 2 Devices or components are shown arranged differently.

[0058] Figure 3 An optical system 300 is shown according to one or more implementations. The optical system 300 can be implemented in a WSS device, for example, for port steering. Figure 2 Similar to the described optical system 200 , the optical system includes a beam steering device 302 and an optical arrangement 304 .

[0059] The beam steering device 302 may be configured with a beam steering dependency that depends on polarization, such as P polarization or S polarization. The optical device 304 may include a plurality of optical components configured to direct two polarized light beams along respective optical paths. The optical device 304 may include an input end 106, an output end 108, a first optical path 110 for a first polarized beam, a second optical path 112 for a second polarized beam, a third optical path 114 for the first polarized beam, and a fourth optical path 116 for the second polarized beam, as combined Figure 2 Similar to what is described.

[0060] In addition, the optical device 304 can generate overlapping polarized beams for beam steering. The optical device 304 can be configured to split an input beam with an arbitrary polarization state into two polarized beams (e.g., a first polarized beam and a second polarized beam) with orthogonal polarizations; rotate the first polarized beam to have the same polarization state as the second polarized beam; make the two polarized beams intersect at the same area on the beam steering device 302, with an intersection angle in the beam steering direction; have equal focal lengths for the two polarized beams; and have the same number of reflections in each optical path of the two polarized beams, so that the beam steering device 302 can steer the two polarized beams in the same direction. Alternatively, the difference between the number of reflections of the two beam paths can be a multiple of 2, so that the beam steering device 302 can steer the two polarized beams in the same direction. The common output direction of the two polarized beams depends on the beam steering angle of the beam steering device 302. Thus, the position of the combined output beam relative to the input beam corresponds to the focal length of switching lens 306 , optical arrangement 304 , and the beam steering angle of beam steering device 302 .

[0061] The optical device 304 may include a polarization beam splitter 118-1 or a vertical birefringent wedge 118-2 as a first optical component 118 that generates two polarized beams from an input beam. In addition, the optical device 304 may include a second optical component 120 (e.g., a HWR). In addition, the optical device 304 may include a switching lens 306, an optical element 308 (e.g., a lens that can collimate light in a first direction and focus light in an opposite second direction), a grating dispersive element 310 for separating wavelengths, an optical element 312 (e.g., a lens that can focus light in a first direction and collimate light in an opposite second direction), and a reflector 314. The beam steering device 302 may be located at a focus of the optical element 312. The switching lens 306 may convert the angle of the output beam to a corresponding port of the WSS device.

[0062] The optical system 300 can be combined with Figure 2The optical device 304 can be configured to operate in a manner similar to the operation of the optical system 200 described above. Therefore, the optical device 304 can be configured to cause the first polarized beam and the second polarized beam to spatially overlap at the beam steering device 302 in the same polarization state. The beam steering device 302 can steer the first polarized beam and the second polarized beam toward the output end 108 so that the first polarized beam and the second polarized beam are directed from the output end 108 in a common output direction.

[0063] As indicated above, Figure 3 Other examples may be provided as examples. Figure 3 Described differently. Figure 3 The number and arrangement of devices and components shown are provided as examples. In practice, there may be additional devices or components, fewer devices or components, different devices or components, or different Figure 3 Devices or components are shown arranged differently.

[0064] FIG. 4A to FIG. 4C An optical system 400 is shown according to one or more implementations. The optical system 400 may be implemented in a WSS device, for example for port steering. The optical system 400 may include a beam steering device 402 and an optical arrangement 404.

[0065] The beam steering device 402 can be configured with a beam steering dependency that depends on linear polarization. For example, the beam steering device 402 can be configured to steer only light with linear polarization. In some implementations, the beam steering device 402 can be a polarization-dependent LCOS array, a polarization-dependent spatial light modulator, or a polarization-dependent light guide array. The beam steering device 402 can be configured to steer two polarized light beams to a common output direction. However, in order to steer two polarized light beams simultaneously, the two polarized light beams incident on the beam steering device 402 must have the same polarization orientation as the polarization on which the beam steering device 402 operates. Therefore, if the beam steering device 402 is configured to steer light with a specific linear polarization, the two polarized light beams must have a specific linear polarization.

[0066] The optical device 404 may include an input end 106 (e.g., an optical input end), an output end 108 (e.g., an optical output end), a first optical path 110 for a first polarized beam, a second optical path 112 for a second polarized beam, a third optical path 114 for the first polarized beam, and a fourth optical path 116 for the second polarized beam. Figure 4A Trajectories of a first polarized beam and a second polarized beam with corresponding polarizations are shown. Figure 4B Trajectories of the first polarized beam and the first reflected polarized beam are shown with actual beam width. Figure 4CTrajectories of a second polarized beam and a second reflected polarized beam having actual beam widths are shown. The first polarized beam and the second polarized beam substantially overlap, if not completely overlap, at the beam steering device 402. The first reflected polarized beam is generated by reflecting the first polarized beam at the beam steering device 402. The second reflected polarized beam is generated by reflecting the second polarized beam at the beam steering device 402.

[0067] The input end 106 can receive an input light beam having any polarization state (e.g., non-polarization state). The first optical path 110 and the second optical path 112 can extend from the input end 106 and intersect at the same incident point on the beam steering device 402. For example, after reflection at the beam steering device 402, the third optical path 114 and the fourth optical path 116 can extend from the beam steering device 402 to the output end 108.

[0068] The optical device 404 may include a polarization grating 406, a first reflector 408 including a first retarder, and a second reflector 410 including a second retarder. The polarization grating 406 may be arranged at the input end 106 and the output end 108. In addition, the polarization grating 406 may split the input beam into two orthogonal polarized beams, the two orthogonal polarized beams including a first polarized beam with left circular polarization (e.g., counterclockwise polarization) and a second polarized beam with right circular polarization (e.g., clockwise polarization). The polarization grating 406 may guide the first polarized beam along the first optical path 110 with left circular polarization and guide the second polarized beam along the second optical path 112 with right circular polarization.

[0069] The first mirror 408 may be disposed on the first optical path 110 between the polarization grating 406 and the beam steering device 402. The first retarder of the first mirror 408 may convert the left circular polarization of the first polarized beam into a linear polarization, and the first mirror 408 may further direct the first polarized beam along the first optical path 110 with a linear polarization.

[0070] The second mirror 410 may be disposed on the second optical path 112 between the polarization grating 406 and the beam steering device 402. The second retarder of the second mirror 410 may convert the right circular polarization of the second polarized beam into a linear polarization, and the second mirror 410 may further direct the second polarized beam along the second optical path 112 with a linear polarization.

[0071] The first polarized beam and the second polarized beam having the same linear polarization spatially overlap at the beam steering device 402. In particular, the first polarized beam and the second polarized beam may at least partially spatially overlap at a target area of ​​the beam steering device 402. For example, at least 90% of a first area where the first polarized beam of the beam steering device 402 is incident on the beam steering device 402 spatially overlaps with a second area where the second polarized beam of the beam steering device 402 is incident on the beam steering device. In some implementations, the first reflector 408 and the second reflector 410 may be configured such that the first polarized beam having a linear polarization and the second polarized beam having a linear polarization completely spatially overlap at the beam steering device 402. The first polarized beam and the second polarized beam may fill or substantially fill an aperture of the beam steering device 402.

[0072] The beam steering device 402 may steer the first polarized beam and the second polarized beam toward the output end 108 so that the first polarized beam and the second polarized beam are directed from the output end 108 in a common output direction, similar to that described above with respect to the optical systems 100 , 200 , and 300 .

[0073] Furthermore, a first optical path length for the first polarized beam to travel from the input end 106 to the output end 108 may be equal to or substantially equal to a second optical path length for the second polarized beam to travel from the input end 106 to the output end 108 .

[0074] The optical device 404 may be configured such that the first optical path 110 has a first reflection number and the second optical path 112 has a second reflection number equal to the first reflection number. Alternatively, the difference between the first reflection number and the second reflection number may be a multiple of two.

[0075] Furthermore, the first mirror 408 and the second mirror 410 may be configured to allow the first polarized beam having linear polarization and the second polarized beam having linear polarization to intersect at the same incident point, wherein the intersection angle is in the beam steering direction of the beam steering device 402 .

[0076] As indicated above, FIG. 4A to FIG. 4C Other examples may be provided as examples. FIG. 4A to FIG. 4C Described differently. FIG. 4A to FIG. 4C The number and arrangement of devices and components shown are provided as examples. In practice, there may be additional devices or components, fewer devices or components, different devices or components, or different FIG. 4A to FIG. 4C Devices or components are shown arranged differently.

[0077] Figure 5A and Figure 5BInput / output direction arrangements 500A and 500B are shown according to one or more implementations. The input / output direction arrangements 500A and 500B may correspond to the input / output direction arrangements of one of the optical systems 100, 200, 300, or 400. The input / output direction arrangements 500A and 500B illustrate reflections at a beam steering device 502 (e.g., LCOS) during zero-order reflection. The input / output direction arrangements 500A and 500B include a plurality of input directions corresponding to one or more input ports, respectively, and a plurality of output directions corresponding to a plurality of output ports, respectively. For example, IN_s and IN_p may correspond to a first optical path 110 and a second optical path 112, respectively, which may correspond to input directions from a first input port. P1_s and P1_p may correspond to reflection paths, which may correspond to output directions of a first output port. In addition, Pn-1_s and Pn-1_p may correspond to reflection paths, which may correspond to output directions of a second output port. Furthermore, Pn_s and Pn_p may correspond to a reflection path, which may correspond to an output direction of the third output port.

[0078] The first optical path 110 may have a first incident angle θ relative to the beam steering device 502. c1_p , and the second optical path 112 may have a second incident angle θ relative to the beam steering device 502 c1_s . The first incident angle θ c1_p With the second incident angle θ c1_s The sum is equal to the angle offset θ offset The beam steering device 502 may reflect the first polarized beam as a first reflected polarized beam on the third optical path 114 toward the output end 108 with a first zero-order reflection (e.g., zero-order diffraction). In addition, the beam steering device 502 may reflect the second polarized beam as a second reflected polarized beam on the fourth optical path 116 toward the output end 108 with a second zero-order reflection. During the zero-order diffraction, the optical device of the optical system may provide an angular offset θ between the first optical path 110 and the second optical path 112 at the beam steering device 102. offset , so that the first reflected polarized beam and the second reflected polarized beam are output from the optical system in a common output direction, and the common output direction is directed away from all output ports of the plurality of output ports. Figure 5A As shown, the common output direction may point outside the range of multiple output directions. Alternatively, as Figure 5B As shown, the common output direction may point between two adjacent output directions among the multiple output directions.

[0079] As indicated above, Figure 5A and Figure 5B Other examples may be provided as examples. Figure 5A and Figure 5B Described differently.

[0080] Figure 6 An input / output direction arrangement 600 is shown according to one or more implementations. The input / output direction arrangement 600 may correspond to an input / output direction arrangement of one of the optical systems 100, 200, 300, or 400. The input / output direction arrangement 600 shows a reflection at a beam steering device 602 (e.g., an LCOS) during a zero-order reflection. The input / output direction arrangement 600 includes a plurality of input directions corresponding to one or more input ports, respectively, and a plurality of output directions corresponding to a plurality of output ports, respectively. In this example, the beam steering device 602 performs active beam steering to direct a positive first-order reflection at a configured output port. Thus, the input port is linked, paired, or otherwise configured with the configured output port. Thus, the first optical path 110 and the second optical path 112 are linked to the configured output port via the third optical path 114 and the fourth optical path 116, respectively.

[0081] During active beam steering, the beam steering device 602 may reflect the first polarized beam as a first reflected polarized beam on the third optical path 114 toward the output end 108 with a first positive first-order reflection (e.g., positive first-order diffraction), and reflect the second polarized beam as a second reflected polarized beam on the fourth optical path 116 toward the output end 108 with a second positive first-order reflection. However, unlike during zero-order diffraction, the optical arrangement of the optical system may provide an angular offset θ between the first optical path 110 and the second optical path 112 at the beam steering device 602. offset , so that the first reflected polarized beam and the second reflected polarized beam are output from the optical system in a common output direction, and the common output direction is directed only to the configured output port selected from the plurality of output ports. In other words, the angle offset θ offset It may be configured to ensure that the common output direction is not directed to any unexpected or undesired output port (eg, at any unconfigured output port) in order to avoid crosstalk between output ports.

[0082] In addition, during active beam steering, the beam steering device 602 can reflect the first polarized beam as a third reflected polarized beam on a fifth optical path toward the output end 108 with a first negative first-order reflection (e.g., negative first-order diffraction), and reflect the second polarized beam as a fourth reflected polarized beam on a sixth optical path toward the output end 108 with a second negative first-order reflection. The third reflected polarized beam and the fourth reflected polarized beam can be interference signals generated by the negative first-order diffraction. The fifth optical path and the sixth optical path can be different from the third optical path 114 and the fourth optical path 116. The optical device of the optical system can provide an angular offset θ between the first optical path and the second optical path at the beam steering device 602. offset, so that the third reflected polarized beam and the fourth reflected polarized beam are output in one or more directions directed away from all of the plurality of output ports. In other words, the angle offset θ offset The first prism 122 and the second prism 124 may be configured to ensure that the third reflected polarized beam and the fourth reflected polarized beam are not directed to any output port in order to avoid crosstalk between the output ports. The reflective sides of the first prism 122 and the second prism 124 may be offset by an angle θ between the first optical path 110 and the second optical path 112. offset Directed in the way.

[0083] In addition, during active beam steering, the beam steering device 602 can reflect the first polarized beam as a fifth reflected polarized beam on a seventh optical path toward the output end 108 with a first second-order reflection (e.g., second-order diffraction), and reflect the second polarized beam as a sixth reflected polarized beam on an eighth optical path toward the output end 108 with a second second-order reflection. The fifth reflected polarized beam and the sixth reflected polarized beam can be interference signals generated by second-order diffraction. The seventh optical path and the eighth optical path can be different from the third optical path, the fourth optical path, the fifth optical path, and the sixth optical path. The optical device of the optical system can provide an angular offset θ between the first optical path and the second optical path at the beam steering device 602. offset , so that the fifth reflected polarized beam and the sixth reflected polarized beam are output in one or more directions directed away from all of the plurality of output ports. In other words, the angle offset θ offset The first prism 122 and the second prism 124 may be configured to ensure that the fifth reflected polarized beam and the sixth reflected polarized beam are not directed to any output port in order to avoid crosstalk between the output ports. The reflective sides of the first prism 122 and the second prism 124 may be offset by an angle θ between the first optical path 110 and the second optical path 112. offset Directed in the way.

[0084] As indicated above, Figure 6 Other examples may be provided as examples. Figure 6 Described differently.

[0085] The following provides an overview of some aspects of the disclosure:

[0086] Aspect 1: An optical system, comprising: a beam steering device, configured with a beam steering dependency depending on a first polarization, wherein the beam steering device is configured to steer only light having the first polarization; and an optical device, comprising an input end, a first optical path, a second optical path, and an output end, wherein the input end is configured to receive an input light beam having an arbitrary polarization state, and wherein the first optical path and the second optical path extend from the input end and intersect at the same incident point on the beam steering device, wherein the optical device further comprises: a first optical component, configured to split the input light beam into two orthogonal polarized beams comprising a first polarized beam and a second polarized beam, wherein the first optical component is configured to guide the first polarized beam along the first optical path with the first polarization, and along guiding the second polarized beam along the second optical path with a second polarization orthogonal to the first polarization; and a second optical component configured to receive the second polarized beam, rotate the second polarization of the second polarized beam to the first polarization, and further guide the second polarized beam with the first polarization along the second optical path, wherein the first optical component and the second optical component are configured so that the first polarized beam with the first polarization and the second polarized beam with the first polarization spatially overlap at the beam steering device, and wherein the beam steering device is configured to steer the first polarized beam and the second polarized beam toward the output end so that the first polarized beam and the second polarized beam are guided from the output end in a common output direction.

[0087] Aspect 2: An optical system according to Aspect 1, wherein the first optical component and the second optical component are configured so that the first polarized beam having the first polarization and the second polarized beam having the first polarization spatially overlap at the beam steering device, wherein at least 90% of the first polarized beam of the beam steering device incident on a first area of ​​the beam steering device spatially overlaps with the second polarized beam of the beam steering device incident on a second area of ​​the beam steering device.

[0088] Aspect 3: An optical system according to any one of Aspects 1 to 2, wherein the first optical component and the second optical component are configured so that the first polarized beam having the first polarization and the second polarized beam having the first polarization completely spatially overlap at the beam steering device.

[0089] Aspect 4: An optical system according to any one of Aspects 1 to 3, wherein the first optical component and the second optical component are configured so that the first polarized beam having the first polarization and the second polarized beam having the first polarization intersect at the same incident point, wherein the intersection angle is in the beam steering direction of the beam steering device.

[0090] Aspect 5: An optical system according to any one of Aspects 1 to 4, wherein the optical device is configured to focus the first polarized beam onto the beam steering device within a first focal depth and in a wavelength dispersion direction, and wherein the optical device is configured to focus the second polarized beam onto the beam steering device within a second focal depth and in the wavelength dispersion direction.

[0091] Aspect 6: The optical system according to any one of aspects 1 to 5, wherein a first optical path length of the first polarized beam from the input end to the output end is equal to a second optical path length of the second polarized beam from the input end to the output end.

[0092] Aspect 7: An optical system according to any one of Aspects 1 to 6, wherein the optical device is configured so that the first optical path has a first reflection number and the second optical path has a second reflection number, the second reflection number is equal to the first reflection number or the difference between the first reflection number and the second reflection number is a multiple of 2.

[0093] Aspect 8: An optical system according to any one of Aspects 1 to 7, wherein the beam steering device is configured to reflect the first polarized beam so that the first polarized beam returns to the second optical path, and wherein the beam steering device is configured to reflect the second polarized beam so that the second polarized beam returns to the first optical path.

[0094] Aspect 9: An optical system according to any one of Aspects 1 to 8, wherein the beam steering device is configured to reflect the first polarized beam as a first reflected polarized beam on a third optical path toward the second optical component, wherein the second optical component is configured to receive the first reflected polarized beam, rotate the first polarization of the first reflected polarized beam to the second polarization, and direct the first reflected polarized beam toward the first optical component with the second polarization, and wherein the first optical component is configured to direct the second reflected polarized beam toward the output end with the second polarization.

[0095] Aspect 10: The optical system according to aspect 9, wherein the beam steering device is configured to reflect the second polarized beam as a second reflected polarized beam towards the first optical component on a fourth optical path, and wherein the first optical component is configured to direct the second reflected polarized beam to the output in the first polarization.

[0096] Aspect 11: The optical system according to aspect 10, wherein the sum of the first optical path and the third optical path representing the first total optical path from the input end to the output end has a first total optical path length, wherein the sum of the second optical path and the fourth optical path representing the second total optical path from the input end to the output end has a second total optical path length, and wherein the first total optical path length is equal to the second total optical path length.

[0097] Aspect 12: The optical system according to aspect 10, wherein the first optical component is configured to combine the first reflected polarized beam and the second reflected polarized beam into a combined output beam and direct the combined output beam at the output end in the common output direction.

[0098] Aspect 13: The optical system according to any one of aspects 1 to 12, wherein the common output direction depends on the beam steering angle of the beam steering device.

[0099] Aspect 14: The optical system according to any one of aspects 1 to 13, wherein the beam steering device is configured to reflect the first polarized beam as a first reflected polarized beam towards the output end on a third optical path, wherein the beam steering device is configured to reflect the second polarized beam as a second reflected polarized beam towards the output end on a fourth optical path, wherein the optical device is configured to combine the first reflected polarized beam and the second reflected polarized beam having orthogonal polarizations into a combined output beam and output the combined output beam at the output end, and wherein the position of the combined output beam relative to the input beam corresponds to the optical path length of the optical device and the beam steering angle of the beam steering device.

[0100] Aspect 15: The optical system according to any one of aspects 1 to 14, wherein the optical system is a WSS, and the beam steering device is configured to steer the light in the port switching direction of the WSS, wherein the port switching direction is perpendicular to the wavelength dispersion direction of the WSS.

[0101] Aspect 16: The optical system according to aspect 15, wherein the WSS is configured to calibrate the first polarized beam and the second polarized beam in the port switching direction and focus the first polarized beam and the second polarized beam in the wavelength dispersion direction.

[0102] Aspect 17: The optical system of any one of aspects 1 to 16, wherein the beam steering device is a liquid crystal on silicon (LCOS) array.

[0103] Aspect 18: The optical system according to any one of aspects 1 to 17, wherein the first polarization and the second polarization are linear polarizations.

[0104] Aspect 19: An optical system according to any one of Aspects 1 to 18, wherein the optical device comprises: a first prism, comprising the input end, the output end, the first optical component, the second optical component and a reflector, wherein the first optical component is a polarization beam splitter arranged on the first optical path and the second optical path, wherein the second optical component is a quarter-wave delay device; and a second prism optically coupled between the first prism and the beam steering device.

[0105] Aspect 20: An optical system according to any one of Aspects 1 to 19, wherein the optical device comprises: a first prism, comprising the input end, the output end and the first optical component, wherein the first optical component is a polarization beam splitter arranged on the first optical path and the second optical path; a second prism, arranged on the second optical path and optically coupled between the first prism and the second optical component; a first redirection prism, arranged on the first optical path and optically coupled between the first prism and the beam steering device, wherein the first redirection prism is configured to direct the first polarized beam to the beam steering device with the first polarization; and a second redirection prism, arranged on the second optical path and optically coupled between the second prism and the beam steering device, wherein the second redirection prism is configured to direct the second polarized beam to the beam steering device with the first polarization, wherein the second optical component is a half-wave delay.

[0106] Aspect 21: An optical system according to any one of Aspects 1 to 20, wherein the optical system is a WSS, the WSS includes multiple input directions corresponding to one or more input ports and multiple output directions corresponding to multiple output ports, wherein the beam steering device is configured to reflect the first polarized beam as a first reflected polarized beam on a third optical path toward the output end by a first zero-order reflection, wherein the beam steering device is configured to reflect the second polarized beam as a second reflected polarized beam on a fourth optical path toward the output end by a second zero-order reflection, and wherein the optical device is configured to provide an angular offset between the first optical path and the second optical path at the beam steering device, so that the first reflected polarized beam and the second reflected polarized beam are output in the common output direction, and the common output direction is directed away from all of the multiple output ports.

[0107] Aspect 22: The optical system according to Aspect 21, wherein the common output direction is outside the range of the plurality of output directions.

[0108] Aspect 23: The optical system according to Aspect 21, wherein the common output direction is between two adjacent output directions among the plurality of output directions.

[0109] Aspect 24: An optical system according to any one of Aspects 1 to 23, wherein the optical system is a WSS, the WSS includes multiple input directions corresponding to one or more input ports and multiple output directions corresponding to multiple output ports, wherein the beam steering device is configured to reflect the first polarized beam as a first reflected polarized beam on a third optical path toward the output end with a first positive first-order reflection, wherein the beam steering device is configured to reflect the second polarized beam as a second reflected polarized beam on a fourth optical path toward the output end with a second positive first-order reflection, and wherein the optical device is configured to provide an angular offset between the first optical path and the second optical path at the beam steering device, so that the first reflected polarized beam and the second reflected polarized beam are output in the common output direction, and the common output direction only points to a configured output port selected from the multiple output ports.

[0110] Aspect 25: The optical system according to aspect 24, wherein the beam steering device is configured to reflect the first polarized beam as a third reflected polarized beam towards the output end on a fifth optical path by a first negative first-order reflection, wherein the beam steering device is configured to reflect the second polarized beam as the fourth reflected polarized beam towards the output end on a sixth optical path by a second negative first-order reflection, and wherein the optical device is configured to provide the angular offset between the first optical path and the second optical path at the beam steering device such that the third reflected polarized beam and the fourth reflected polarized beam are output in one or more directions away from all of the plurality of output ports.

[0111] Aspect 26: The optical system according to aspect 24, wherein the beam steering device is configured to reflect the first polarized beam as a third reflected polarized beam towards the output end on a fifth optical path by a first second-order reflection, wherein the beam steering device is configured to reflect the second polarized beam as the fourth reflected polarized beam towards the output end on a sixth optical path by a second second-order reflection, and wherein the optical device is configured to provide the angular offset between the first optical path and the second optical path at the beam steering device such that the third reflected polarized beam and the fourth reflected polarized beam are output in one or more directions away from all of the plurality of output ports.

[0112] Aspect 27: An optical system, comprising: a beam steering device configured with a beam steering dependency depending on linear polarization, wherein the beam steering device is configured to steer only light having the linear polarization; and an optical device comprising an input end, a first optical path, a second optical path, and an output end, wherein the input end is configured to receive an input light beam having an arbitrary polarization state, and wherein the first optical path and the second optical path extend from the input end and intersect at the same incident point on the beam steering device, wherein the optical device further comprises: a polarization grating arranged at the input end and the output end, wherein the polarization grating is configured to split the input light beam into two orthogonal polarized beams, the two orthogonal polarized beams comprising a first polarized beam having left circular polarization and a second polarized beam having left circular polarization. A second polarized beam having right circular polarization, a first reflector comprising a first delay device, wherein the first reflector is arranged on the first optical path between the polarization grating and the beam steering device, wherein the first reflector is configured to convert the left circular polarization of the first polarized beam into the linear polarization and further guide the first polarized beam along the first optical path with the linear polarization; and a second reflector comprising a second delay device, wherein the second reflector is arranged on the second optical path between the polarization grating and the beam steering device, wherein the second reflector is configured to convert the right circular polarization of the second polarized beam into the linear polarization and further guide the second polarized beam along the second optical path with the linear polarization.

[0113] Aspect 28: The optical system according to Aspect 27, wherein a first optical path length of the first polarized beam traveling from the input end to the output end is equal to a second optical path length of the second polarized beam traveling from the input end to the output end.

[0114] Aspect 29: An optical system according to any one of Aspects 27 to 28, wherein the optical device is configured so that the first optical path has a first number of reflections and the second optical path has a second number of reflections, the second number of reflections is equal to the first number of reflections, or the difference between the first number of reflections and the second number of reflections is a multiple of 2.

[0115] Aspect 30: An optical system according to any one of Aspects 27 to 29, wherein the first reflector and the second reflector are configured so that the first polarized beam having the linear polarization and the second polarized beam having the linear polarization intersect at the same incident point, wherein the intersection angle is in the beam steering direction of the beam steering device.

[0116] Aspect 31: A system configured to perform one or more operations according to one or more of aspects 1 to 30.

[0117] Aspect 32: An apparatus comprising means for performing one or more operations according to one or more of aspects 1 to 30.

[0118] Aspect 33: A non-transitory computer-readable medium storing an instruction set, wherein the instruction set includes one or more instructions, and when the one or more instructions are executed by a device, the device performs one or more operations according to one or more aspects of aspects 1 to 30.

[0119] Aspect 34: A computer program product comprising instructions or codes for performing one or more operations according to one or more of aspects 1 to 30.

[0120] The above disclosure provides illustration and description, but is not intended to be exhaustive or to limit the implementation to the precise form disclosed. Modifications and variations may be made in accordance with the above disclosure, or may be obtained from the practice of the implementation. In addition, unless the above disclosure explicitly provides a reason why one or more implementations may not be combined, any implementation described herein may be combined.

[0121] As used herein, the terms "substantially" and "approximately" mean "within reasonable tolerances of manufacturing and measurement." For example, the terms "substantially" and "approximately" may be used herein to account for small manufacturing tolerances or other factors deemed acceptable by the industry (e.g., within 5%) without departing from aspects of the implementations described herein. For example, a resistor having an approximate resistance value may actually have a resistance that is within 5% of the approximate resistance value. As another example, an approximate signal value may actually have a signal value that is within 5% of the approximate signal value.

[0122] Although specific combinations of features are cited 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 that are not specifically cited in the claims and / or disclosed in the specification. Although each dependent claim listed below may be directly subordinate to only one claim, the disclosure of the various implementations includes the combination of each dependent claim with each other claim in the claim set. As used herein, a phrase referring to "at least one of" a list of items refers to any combination of those items, including a single member. As an example, "at least one of the following: a, b, or c" is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with multiple identical items.

[0123] When a component or one or more components (e.g., a laser emitter or one or more laser emitters) is described or claimed (within a single claim or across multiple claims) as performing multiple operations or being configured to perform multiple operations, the language is intended to broadly cover a variety of architectures and environments. For example, unless otherwise expressly claimed (e.g., via the use of "first component" and "second component" or other language that distinguishes components in the claims), the language is intended to cover a single component that performs or is configured to perform all operations, a group of components that collectively perform or are configured to perform all operations, a first component that performs or is configured to perform a first operation and a second component that performs or is configured to perform a second operation, or any combination of components that perform or are configured to perform operations. For example, when a claim is of the form "one or more components are configured to: perform X; perform Y; and perform Z", the claim should be interpreted as "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".

[0124] Unless clearly described, any element, action or instruction used in this article should not be interpreted as critical or essential. In addition, as used herein, the articles "one" and "a piece" are intended to include one or more projects, and can be used interchangeably with "one or more". In addition, as used herein, the article "the" is intended to include one or more projects related to the article "the", and can be used interchangeably with "one or more". In addition, as used herein, the term "group" is intended to include one or more projects (for example, a combination of related projects, unrelated projects or related projects and unrelated projects), and can be used interchangeably with "one or more". In the case of only intending a project, the phrase "only one" or similar language is used. In addition, as used herein, the term "has", "have", "having" etc. are intended to become open terms. In addition, unless otherwise clearly stated, the phrase "based on" is intended to mean "at least partially based on". In addition, as used herein, the term "or" is intended to be inclusive when used in series, and can be used interchangeably with "and / or", unless otherwise clearly stated (for example, if used in combination with "any one of them" or "only one of them"). In addition, for ease of description, spatially relative terms such as "below," "below," "above," "above," etc. may be used herein to describe the relationship of one element or feature to another element or feature shown in the figures. Spatially relative terms are intended to encompass different orientations of the device, equipment, and / or element in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein may be interpreted accordingly.

Claims

1. An optical system, comprising: a beam steering device configured with a beam steering dependency depending on a first polarization, wherein the beam steering device is configured to only steer light having the first polarization; as well as An optical device comprising an input end, a first optical path and a second optical path, and an output end, wherein the input end is configured to receive an input beam having an arbitrary polarization state, and wherein the first optical path and the second optical path extend from the input end and intersect at the same incident point on the beam steering device, The optical device further comprises: a first optical component configured to split the input beam into two orthogonal polarized beams including a first polarized beam and a second polarized beam, wherein the first optical component is configured to direct the first polarized beam along the first optical path with the first polarization and to direct the second polarized beam along the second optical path with a second polarization, the second polarization being orthogonal to the first polarization; as well as a second optical component configured to receive the second polarized beam, rotate the second polarization of the second polarized beam to the first polarization, and further direct the second polarized beam with the first polarization along the second optical path, wherein the first optical component and the second optical component are configured such that the first polarized beam having the first polarization and the second polarized beam having the first polarization spatially overlap at the beam steering device, and Wherein the beam steering device is configured to steer the first polarized beam and the second polarized beam toward the output end, so that the first polarized beam and the second polarized beam are directed from the output end in a common output direction.

2. The optical system of claim 1 , wherein the first optical component and the second optical component are configured such that the first polarized beam having the first polarization and the second polarized beam having the first polarization spatially overlap at the beam steering device, Wherein at least 90% of a first area of ​​the beam steering device at which the first polarized beam is incident on the beam steering device spatially overlaps with a second area of ​​the beam steering device at which the second polarized beam is incident on the beam steering device.

3. The optical system of claim 1, wherein the first optical component and the second optical component are configured such that the first polarized beam having the first polarization and the second polarized beam having the first polarization completely spatially overlap at the beam steering device.

4. An optical system according to claim 1, wherein the first optical component and the second optical component are configured so that the first polarized beam having the first polarization and the second polarized beam having the first polarization intersect at the same incident point, wherein the intersection angle is in the beam steering direction of the beam steering device.

5. The optical system of claim 1 , wherein the optical arrangement is configured to focus the first polarized beam onto the beam steering device in a wavelength dispersion direction within a first focal depth, and Wherein the optical arrangement is configured to focus the second polarized beam onto the beam steering device within a second focal depth and in the wavelength dispersion direction.

6. The optical system of claim 1, wherein a first optical path length of the first polarized beam traveling from the input end to the output end is equal to a second optical path length of the second polarized beam traveling from the input end to the output end.

7. An optical system according to claim 1, wherein the optical device is configured so that the first optical path has a first reflection number and the second optical path has a second reflection number, the second reflection number is equal to the first reflection number or the difference between the first reflection number and the second reflection number is a multiple of 2.

8. The optical system of claim 1, wherein the beam steering device is configured to reflect the first polarized beam so that the first polarized beam is folded back to the second optical path, and The beam steering device is configured to reflect the second polarized beam so that the second polarized beam returns to the first optical path.

9. The optical system of claim 1, wherein the beam steering device is configured to reflect the first polarized beam as a first reflected polarized beam on a third optical path toward the second optical component, wherein the second optical component is configured to receive the first reflected polarized beam, rotate the first polarization of the first reflected polarized beam to the second polarization, and direct the first reflected polarized beam toward the first optical component at the second polarization, and Wherein the first optical component is configured to direct the first reflected polarized beam toward the output end at the second polarization.

10. The optical system of claim 9, wherein the beam steering device is configured to reflect the second polarized beam as a second reflected polarized beam on a fourth optical path toward the first optical component, and Wherein the first optical component is configured to direct the second reflected polarized beam toward the output end at the first polarization.

11. The optical system according to claim 10, wherein the sum of the first optical path and the third optical path representing a first total optical path from the input end to the output end has a first total optical path length, wherein the sum of the second optical path and the fourth optical path representing a second total optical path from the input end to the output end has a second total optical path length, and The first total optical path length is substantially equal to the second total optical path length.

12. The optical system of claim 10, wherein the first optical component is configured to combine the first reflected polarized beam with the second reflected polarized beam into a combined output beam and direct the combined output beam in the common output direction at the output end.

13. The optical system of claim 1, wherein the common output direction depends on a beam steering angle of the beam steering device.

14. The optical system of claim 1, wherein the beam steering device is configured to reflect the first polarized beam as a first reflected polarized beam on a third optical path toward the output end, wherein the beam steering device is configured to reflect the second polarized beam into a second reflected polarized beam on a fourth optical path toward the output end, wherein the optical device is configured to combine the first reflected polarized beam and the second reflected polarized beam having orthogonal polarizations into a combined output beam and output the combined output beam at the output end, and Wherein the position of the combined output beam relative to the input beam corresponds to the optical path length of the optical arrangement and the beam steering angle of the beam steering device.

15. The optical system according to claim 1, wherein the optical system is a wavelength selective switch (WSS), and the beam steering device is configured to steer the light in a port switching direction of the WSS, wherein the port switching direction is perpendicular to a wavelength dispersion direction of the WSS. 16 . The optical system of claim 15 , wherein the WSS is configured to collimate the first polarized beam and the second polarized beam in the port switching direction and focus the first polarized beam and the second polarized beam in the wavelength dispersion direction.

17. The optical system of claim 1, wherein the beam steering device is a Liquid Crystal on Silicon (LCOS) array.

18. The optical system of claim 1, wherein the first polarization and the second polarization are linear polarizations.

19. The optical system of claim 1, wherein the optical device comprises: a first prism, comprising the input end, the output end, the first optical component, the second optical component and a reflector, The first optical component is a polarization beam splitter arranged on the first optical path and the second optical path, wherein the second optical component is a quarter wave retarder, wherein the first optical component, the second optical component and the reflector are arranged on the second optical path; and A second prism is optically coupled between the first prism and the beam steering device.

20. The optical system of claim 1, wherein the optical device comprises: A first prism, comprising the input end, the output end and the first optical component, wherein the first optical component is a polarization beam splitter arranged on the first optical path and the second optical path; a second prism disposed on the second optical path and optically coupled between the first prism and the second optical component; a first redirection prism disposed on the first optical path and optically coupled between the first prism and the beam steering device, wherein the first redirection prism is configured to direct the first polarized beam toward the beam steering device at the first polarization; as well as a second redirection prism disposed on the second optical path and optically coupled between the second prism and the beam steering device, wherein the second redirection prism is configured to direct the second polarized beam at the first polarization toward the beam steering device, Wherein the second optical component is a half-wave retarder.

21. The optical system according to claim 1, wherein the optical system is a wavelength selective switch (WSS), the WSS comprising a plurality of input directions corresponding to one or more input ports respectively and a plurality of output directions corresponding to a plurality of output ports respectively, wherein the beam steering device is configured to reflect the first polarized beam as a first reflected polarized beam on a third optical path toward the output end by a first zero-order reflection, wherein the beam steering device is configured to reflect the second polarized beam as a second reflected polarized beam on a fourth optical path toward the output end by a second zero-order reflection, and The optical device is configured to provide an angular offset between the first optical path and the second optical path at the beam steering device, so that the first reflected polarized beam and the second reflected polarized beam are output in the common output direction, and the common output direction is directed away from all of the multiple output ports.

22. The optical system of claim 21, wherein the common output direction is outside the range of the plurality of output directions.

23. The optical system of claim 21, wherein the common output direction is between two adjacent output directions of the plurality of output directions.

24. The optical system according to claim 1, wherein the optical system is a wavelength selective switch (WSS), the WSS comprising a plurality of input directions respectively corresponding to one or more input ports and a plurality of output directions respectively corresponding to a plurality of output ports, wherein the beam steering device is configured to reflect the first polarized beam as a first reflected polarized beam on a third optical path toward the output end with a first positive first-order reflection, wherein the beam steering device is configured to reflect the second polarized beam as a second reflected polarized beam on a fourth optical path toward the output end with a second positive first-order reflection, and The optical device is configured to provide an angular offset between the first optical path and the second optical path at the beam steering device, so that the first reflected polarized beam and the second reflected polarized beam are output in the common output direction, and the common output direction only points to a configured output port selected from the multiple output ports.

25. The optical system according to claim 24, wherein the beam steering device is configured to reflect the first polarized beam as a third reflected polarized beam on a fifth optical path toward the output end by a first negative first order reflection, wherein the beam steering device is configured to reflect the second polarized beam as a fourth reflected polarized beam on a sixth optical path toward the output end by a second negative first order reflection, and Wherein the optical device is configured to provide the angular offset between the first optical path and the second optical path at the beam steering device so that the third reflected polarized beam and the fourth reflected polarized beam are output in one or more directions directed away from all of the multiple output ports.

26. The optical system according to claim 24, wherein the beam steering device is configured to reflect the first polarized beam as a third reflected polarized beam on a fifth optical path toward the output end by a first second-order reflection, wherein the beam steering device is configured to reflect the second polarized beam as a fourth reflected polarized beam on a sixth optical path toward the output end by a second second-order reflection, and Wherein the optical device is configured to provide the angular offset between the first optical path and the second optical path at the beam steering device so that the third reflected polarized beam and the fourth reflected polarized beam are output in one or more directions directed away from all of the multiple output ports.

27. An optical system comprising: a beam steering device configured with a beam steering dependency depending on a linear polarization, wherein the beam steering device is configured to only steer light having said linear polarization; as well as An optical device comprising an input end, a first optical path and a second optical path, and an output end, wherein the input end is configured to receive an input beam having an arbitrary polarization state, and wherein the first optical path and the second optical path extend from the input end and intersect at the same incident point on the beam steering device, The optical device further comprises: a polarization grating arranged at the input end and the output end, wherein the polarization grating is configured to split the input beam into two orthogonal polarized beams, the two orthogonal polarized beams comprising a first polarized beam with left circular polarization and a second polarized beam with right circular polarization, wherein the polarization grating is configured to direct the first polarized beam along the first optical path with the left circular polarization and to direct the second polarized beam along the second optical path with the right circular polarization; a first reflector comprising a first retarder, wherein the first reflector is arranged on the first optical path between the polarization grating and the beam steering device, wherein the first reflector is configured to convert the left circular polarization of the first polarized beam into the linear polarization and to guide the first polarized beam further along the first optical path with the linear polarization; and a second reflector comprising a second retarder, wherein the second reflector is arranged on the second optical path between the polarization grating and the beam steering device, wherein the second reflector is configured to convert the right circular polarization of the second polarized beam into the linear polarization and to guide the second polarized beam further along the second optical path with the linear polarization, Wherein the beam steering device is configured to steer the first polarized beam and the second polarized beam towards the output end, such that the first polarized beam and the second polarized beam are directed from the output end in a common output direction.

28. The optical system of claim 27, wherein a first optical path length of the first polarized beam traveling from the input end to the output end is equal to or substantially equal to a second optical path length of the second polarized beam traveling from the input end to the output end.

29. An optical system according to claim 27, wherein the optical device is configured so that the first optical path has a first reflection number and the second optical path has a second reflection number, the second reflection number is equal to the first reflection number or the difference between the first reflection number and the second reflection number is a multiple of 2.

30. An optical system according to claim 27, wherein the first reflector and the second reflector are configured so that the first polarized beam having the linear polarization and the second polarized beam having the linear polarization intersect at the same incident point, wherein the intersection angle is in the beam steering direction of the beam steering device.

Images