Polarization beam splitting and combining hybrid
By setting beam combining and splitting units and steering units on the substrate, the polarization beam combiner solves the problems of high loss, low extinction ratio and large size in the prior art, and realizes a miniaturized and low-loss optical path system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANGHAI PRECILASERS TECH CO LTD
- Filing Date
- 2022-12-14
- Publication Date
- 2026-07-24
Smart Images
Figure CN115793146B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of optical technology, and more particularly to a polarization beam splitter and combiner. Background Technology
[0002] Fiber polarization beam splitters and combiners integrate the functions of polarization beam splitting and combining, and have important applications in fiber optic communication, fiber optic sensors, biomedical instruments, and metrology instruments. Polarization beam splitters and combiners based on fused biconical tapers require cascading fiber splices in multi-path configurations to achieve splits such as 1 to 2, 2 to 4, 4 to 8, 2 to 2, 2 to 4, or 2 to 8. Such cascading results in high loss, significant extinction ratio attenuation, and the inability to simultaneously supply four paths. Furthermore, due to the presence of fibers and splices, they require encapsulation in a box, leading to a relatively large size. Summary of the Invention
[0003] To address the shortcomings of existing polarization beam splitters and combiners based on fused tapers, such as high loss, large extinction ratio attenuation, and large size, this invention provides a polarization beam splitter and combiner.
[0004] The present invention provides a polarization beam splitter and combiner, comprising a substrate, a beam combining unit, a beam splitting unit, and a steering unit. The substrate includes a first surface and a second surface disposed opposite to each other. The beam combining unit is disposed on the first surface, and the beam splitting unit is disposed on the second surface. The steering unit is disposed on one side of the substrate. The output end of the beam splitting unit and the input end of the beam combining unit are both located on the other side of the substrate. The combined beam light after beam combining by the beam combining unit is incident into the beam splitting unit through the steering unit for beam splitting.
[0005] Preferably, the beam combining unit includes an N-input module and a beam combining module, and the beam splitting unit includes an M-input output module and a beam splitting module, where M and N are both greater than or equal to 2. The N input beams entering from the N-input module are incident on the beam combining module, and the beam combined by the beam combining module is incident on the beam splitting module through a steering unit. The M beams split by the beam splitting module are output through the M-input output module.
[0006] Furthermore, the N-type output module includes a first collimator, a second collimator, a third collimator, and a fourth collimator, and the beam combining module includes a first reflector, a first beam combiner, a second beam combiner, a third beam combiner, and a second reflector. The first, second, third, and fourth collimators are sequentially disposed on the first surface at the end furthest from the steering unit. The first reflector, the first beam combiner, the second beam combiner, the third beam combiner, and the second reflector are all disposed on the first surface. The first reflector corresponds to the first collimator, and the first beam combiner corresponds to the second collimator. The devices are configured accordingly: the second beam combiner corresponds to the steering unit; the third beam combiner corresponds to the third collimator; and the second reflector corresponds to the fourth collimator. The first reflector includes a first reflecting surface; the first beam combiner includes a first transmitting surface and a first beam combining surface; the second beam combiner includes a second transmitting surface and a second beam combining surface; the third beam combiner includes a third transmitting surface and a third beam combining surface; the second reflector includes a second reflecting surface; the first reflecting surface and the first beam combining surface are positioned opposite each other; the first beam combining surface and the second transmitting surface are positioned opposite each other; and the second reflecting surface and the third transmitting surface are positioned opposite each other. The third and second beam combining surfaces are positioned opposite each other, with the second beam combining surface and the steering unit positioned opposite each other. The first collimated light, entering through the first collimator, is incident on the first reflecting surface, reflected, and then incident on the first beam combining surface, where it is reflected again. The second collimated light, entering through the second collimator, is incident on the first transmission surface, enters the interior of the first beam combining member, and then exits from the first beam combining surface, combining with the first collimated light reflected from the first beam combining surface to form the first combined beam. The first combined beam is then incident on the second transmission surface and enters the second... Inside the beam combiner, the light exits from the second beam combiner surface; the fourth collimated light, entering through the fourth collimator, is incident on the second reflecting surface, and after being reflected on the second reflecting surface, it is incident on the third transmitting surface, enters the third beam combiner, and exits from the third beam combiner surface; the third collimated light, entering through the third collimator, is incident on the third beam combiner surface, and after being reflected on the third beam combiner surface, it combines with the exited fourth collimated light to form the second beam combiner light; the second beam combiner light is incident on the second beam combiner surface, and after being reflected on the second beam combiner surface, it combines with the exited first beam combiner light to form the third beam combiner light, which is then incident on the steering unit.
[0007] Further, the M-type output module includes a fifth collimator, a sixth collimator, a seventh collimator, and an eighth collimator. The fractional module includes a third reflector, a first beam splitter, a second beam splitter, a third beam splitter, and a fourth reflector. The fifth, sixth, seventh, and eighth collimators are sequentially disposed on the second surface at the end furthest from the steering unit. The third reflector, the first beam splitter, the second beam splitter, the third beam splitter, and the fourth reflector are disposed on the second surface. The third reflector corresponds to the fifth collimator, the first beam splitter corresponds to the sixth collimator, the second beam splitter corresponds to the steering unit, the third beam splitter corresponds to the seventh collimator, and the fourth reflector corresponds to the eighth collimator. The third reflector includes a third reflecting surface. The first beam splitter includes a first beam splitting surface and a first exiting surface. The second beam splitter includes a second beam splitting surface and a second exiting surface. The third beam splitter includes a third beam splitting surface and a third exiting surface. The fourth reflector includes a fourth reflecting surface. The third reflecting surface and the first beam splitting surface are disposed opposite each other. The beam-splitting surface and the second exit surface are arranged opposite to each other. The second beam-splitting surface is arranged opposite to the steering unit. The third beam-splitting surface is arranged opposite to the second beam-splitting surface. The fourth reflecting surface is arranged opposite to the third exit surface. The third combined beam, after being incident on the second beam-splitting surface via the steering unit, is split into a first transmitted beam and a first reflected beam. The first transmitted beam enters the interior of the second beam-splitting element, exits from the second exit surface, and then enters the first beam-splitting surface, where it is split into a second reflected beam and a second transmitted beam. The second reflected beam enters the interior of the second beam-splitting element. The second transmitted beam exits from the second exit surface and then enters the first beam-splitting surface, where it is split into a second reflected beam and a second transmitted beam. The light reaches the third reflecting surface, and after reflection, it is emitted through the fifth collimator. The second transmitted light enters the interior of the first beam splitter, exits from the first exit surface, and is emitted through the sixth collimator. The first reflected light enters the third beam splitter, and is split into the third reflected light and the third transmitted light on the third beam splitter. The third reflected light is emitted through the seventh collimator. The third transmitted light enters the interior of the third beam splitter, exits from the third exit surface, and enters the fourth reflecting surface. After reflection on the fourth reflecting surface, it is emitted through the eighth collimator.
[0008] Furthermore, the steering unit includes a steering prism, and the third beam of light is incident on the second beam splitter after undergoing two 90-degree reflections within the steering prism.
[0009] Furthermore, the beam splitting module also includes a second polarization beam combiner / splitter, which is disposed on the second surface between the second beam splitter and the steering unit. The third beam combined sequentially passes through the steering unit and the second polarization beam combiner / splitter before being incident on the second beam splitting surface.
[0010] Furthermore, the beam combining unit and the beam splitting unit are symmetrically arranged about the substrate. The fifth collimator corresponds to the first collimator, the sixth collimator corresponds to the second collimator, the seventh collimator corresponds to the third collimator, the eighth collimator corresponds to the fourth collimator, the third reflector corresponds to the first reflector, the first beam splitter corresponds to the first beam combining unit, the second beam splitter corresponds to the second beam combining unit, the third beam splitter corresponds to the third beam combining unit, and the fourth reflector corresponds to the second reflector.
[0011] Furthermore, the first beam combiner, the second beam combiner, the third beam combiner, the first beam splitter, the second beam splitter, and the third beam splitter are all beam splitters or wavelength division multiplexing (WDM) sheets.
[0012] Furthermore, the first, second, third, and fourth reflecting surfaces are all 45-degree reflecting surfaces.
[0013] Furthermore, the beam combining module also includes a first polarization beam combiner / splitter, which is disposed on the first surface between the second beam combiner and the steering unit. The third beam combined light is incident on the steering unit through the first polarization beam combiner / splitter.
[0014] Compared with the prior art, the polarization beam splitter and combiner of the present invention significantly reduces the volume of the beam splitter and combiner by respectively setting the beam combining unit and the beam splitting unit on two surfaces of the substrate, with the output end of the beam splitting unit and the incident end of the beam combining unit located on the same side of the substrate and adopting a single-sided structure. By setting a steering unit at the edge of the substrate, the combined light after beam combining by the beam combining unit can be incident into the beam splitting unit for beam splitting. While keeping the volume of the beam splitter and combiner small, the normal operation of the beam splitter and combiner is guaranteed. Attached Figure Description
[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0016] Figure 1 This is a schematic diagram of a polarization beam splitter and combiner according to an embodiment of the present invention.
[0017] Figure 2 This is a schematic diagram of a polarization beam splitter and combiner according to another embodiment of the present invention.
[0018] Figure 3 This is a front structural schematic diagram of a polarization beam splitter and combiner according to a third embodiment of the present invention.
[0019] Figure 4 This is a schematic diagram of the reverse side structure of a polarization beam splitter and combiner according to a third embodiment of the present invention.
[0020] Figure 5 This is a front structural schematic diagram of a polarization beam splitter and combiner according to the fourth embodiment of the present invention.
[0021] Figure 6 This is a schematic diagram of the reverse side structure of a polarization beam splitter and combiner according to the fourth embodiment of the present invention.
[0022] Figure 7 This is a front structural schematic diagram of a polarization beam splitter and combiner according to the fifth embodiment of the present invention.
[0023] Figure 8 This is a schematic diagram of the reverse side structure of a polarization beam splitter and combiner according to the fifth embodiment of the present invention.
[0024] Figure 9 This is a schematic diagram of the structure of a first polarization beam combiner / splitter according to an embodiment of the present invention.
[0025] Figure 10 This is a schematic diagram of the structure of a steering prism according to an embodiment of the present invention. Detailed Implementation
[0026] To provide a further understanding of the purpose, structure, features, and functions of the present invention, detailed descriptions are provided below with reference to specific embodiments.
[0027] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0028] Please see Figure 1 , Figure 1This is a schematic diagram of a polarization beam splitter and combiner according to an embodiment of the present invention. In this embodiment, the polarization beam splitter and combiner includes a substrate 1, a beam combining unit 2, a beam splitting unit 3, and a steering unit 4. The substrate 1 includes a first surface 11 and a second surface 12 disposed opposite to each other. The beam combining unit 2 is disposed on the first surface 11, and the beam splitting unit 3 is disposed on the second surface 12. The steering unit 4 is disposed on one side of the substrate 1. The output end of the beam splitting unit 3 and the input end of the beam combining unit 2 are both located on the other side of the substrate 1. The combined beam light after beam combining by the beam combining unit 2 is incident into the beam splitting unit 3 through the steering unit 4 for beam splitting.
[0029] This polarization beam splitter and combiner is designed by placing the beam combining unit 2 and the beam splitting unit 3 on two surfaces of the substrate 1, with the output end of the beam splitting unit 3 and the incident end of the beam combining unit 2 located on the same side of the substrate 1. This single-sided structure significantly reduces the volume of the beam splitter and combiner. By setting a steering unit 4 at the edge of the substrate 1, the combined light from the beam combining unit 2 can be incident into the beam splitting unit 3 for beam splitting. This design ensures the normal operation of the beam splitter and combiner while maintaining a small volume.
[0030] Preferably, the beam splitter and beam combiner further includes a housing 5, and the substrate 1, beam combining unit 2, beam splitting unit 3 and steering unit 4 are all disposed inside the housing 5, so as to make the beam splitter and beam combiner structure more stable and ensure service life.
[0031] Please see Figure 2 , Figure 2 This is a schematic diagram of a polarization beam splitter and combiner according to another embodiment of the present invention. Figure 1 Compared to the previous embodiment, in this embodiment, the beam combining unit 2 includes an N-input module 210 and a beam combining module 220, and the beam splitting unit 3 includes an M-input output module 310 and a beam splitting module 320. M and N are both greater than or equal to 2. The N input beams entering through the N-input module 210 are incident on the beam combining module 220. The beam combined by the beam combining module 220 is incident on the beam splitting module 320 through the steering unit 4. The M beams split by the beam splitting module 320 are output through the M-input output module 310.
[0032] This polarization beam splitter and combiner combines N input beams into a single beam using a beam combining module 220, and then splits the single beam into M beams using a beam splitting module 320, achieving N-in, M-out. N and M can be the same or different.
[0033] Please refer to the above. Figure 3 and Figure 4 , Figure 3 This is a front view of a polarization beam splitter and combiner according to a third embodiment of the present invention. Figure 4 This is a schematic diagram of the reverse side structure of a polarization beam splitter and combiner according to a third embodiment of the present invention. In this embodiment, the polarization beam splitter and combiner has a 4-input, 4-output structure, where N and M are both 4.
[0034] Please see Figure 3 The N-type input module 210 includes a first collimator 21, a second collimator 22, a third collimator 23, and a fourth collimator 24. The beam combining module 220 includes a first reflector 25, a first beam combiner 26, a second beam combiner 27, a third beam combiner 28, and a second reflector 29. The first collimator 21, the second collimator 22, the third collimator 23, and the fourth collimator 24 are sequentially disposed on the first surface 11 at one end away from the steering unit 4. The first reflector 25, the first beam combiner 26, the second beam combiner 27, the third beam combiner 28, and the second reflector 29 are all disposed on the first surface 11. The first reflector 25 is disposed corresponding to the first collimator 21, the first beam combiner 26 is disposed corresponding to the second collimator 22, the second beam combiner 27 is disposed corresponding to the steering unit 4, and the third beam combiner 28 is disposed corresponding to the steering unit 4. The first reflector 28 is correspondingly arranged with the third collimator 23, and the second reflector 29 is correspondingly arranged with the fourth collimator 24. The first reflector 25 includes a first reflecting surface 251, the first beam combiner 26 includes a first transmitting surface 261 and a first beam combining surface 262, the second beam combiner 27 includes a second transmitting surface 271 and a second beam combining surface 272, the third beam combiner 28 includes a third transmitting surface 281 and a third beam combining surface 282, and the second reflector 29 includes a second reflecting surface 291. The first reflecting surface 251 and the first beam combining surface 262 are arranged opposite to each other, the first beam combining surface 262 and the second transmitting surface 271 are arranged opposite to each other, the second reflecting surface 291 and the third transmitting surface 281 are arranged opposite to each other, the third beam combining surface 282 and the second beam combining surface 272 are arranged opposite to each other, and the second beam combining surface 272 is arranged opposite to the steering unit 4.
[0035] The first collimated light entering through the first collimator 21 is incident on the first reflecting surface 251, and after being reflected on the first reflecting surface 251, it is incident on the first combining surface 262 and is reflected on the first combining surface 262. The second collimated light entering through the second collimator 22 is incident on the first transmitting surface 261, enters the interior of the first combining member 26, and then exits from the first combining surface 262, where it is combined with the first collimated light reflected on the first combining surface 262 to form the first combined light. The first combined light is incident on the second transmitting surface 271, enters the interior of the second combining member 27, and then exits from the second combining surface 272. The fourth collimated light entering through the fourth collimator 24 is incident on the second reflecting surface 291. After being reflected on the second reflecting surface 291, it is incident on the third transmitting surface 281, enters the interior of the third beam combiner 28, and exits from the third beam combiner surface 282. The third collimated light entering through the third collimator 23 is incident on the third beam combiner surface 282. After being reflected on the third beam combiner surface 282, it is combined with the exited fourth collimated light to form the second beam combiner. The second beam combiner is incident on the second beam combiner surface 272. After being reflected on the second beam combiner surface 272, it is combined with the exited first beam combiner to form the third beam combiner, which is then incident on the steering unit 4.
[0036] The beam combining module 220 uses a first reflector 25, a first beam combining component 26, a second beam combining component 27, a third beam combining component 28, and a second reflector 29 to combine the collimated light entering the four collimators, avoiding fiber fusion splicing, reducing loss, ensuring extinction ratio, and facilitating the integration of the optical path system, making the system compact and miniaturized.
[0037] Preferably, the first collimator 21, the second collimator 22, the third collimator 23, and the fourth collimator 24 are all polarization-maintaining collimators, and the polarized light is transmitted along the slow axis of the optical fiber in the polarization-maintaining collimator.
[0038] Preferably, the beam combining module 220 further includes a first polarization beam combiner / splitter 20, which is disposed on the first surface 11 at a position between the second beam combiner 27 and the steering unit 4. The third beam combined light is incident on the steering unit 4 through the first polarization beam combiner / splitter 20 to polarize the third beam combined light and improve the extinction ratio.
[0039] Please see Figure 9 , Figure 9This is a schematic diagram of the structure of a first polarization beam combiner / splitter 20 according to an embodiment of the present invention. The first polarization beam combiner / splitter 20 includes a first right-angle prism 201 and a second right-angle prism 202. The first right-angle prism 201 includes a first incident end face 2011 and a first exit end face 2012 disposed opposite to each other. The second right-angle prism 202 includes a second incident end face 2021 and a second exit end face 2022 disposed opposite to each other. The first incident end face 2011 is disposed opposite to the second beam combining surface 272. The first exit end face 2012 and the second incident end face 2021 are bonded together. The second exit end face 2022 is disposed opposite to the steering unit 4.
[0040] The third beam of light enters the first right-angle prism 201 from the first incident end face 2011, then enters the second right-angle prism 202 through the first exit end face 2012 and the second incident end face 2021, and then exits from the second exit end face 2022 and enters the steering unit 4.
[0041] Please see Figure 4 The M-type output module 310 includes a fifth collimator 31, a sixth collimator 32, a seventh collimator 33, and an eighth collimator 34. The beam splitting module 320 includes a third reflector 35, a first beam splitter 36, a second beam splitter 37, a third beam splitter 38, and a fourth reflector 39. The fifth collimator 31, the sixth collimator 32, the seventh collimator 33, and the eighth collimator 34 are sequentially disposed on the second surface 12 at one end away from the steering unit 4. The third reflector 35, the first beam splitter 36, the second beam splitter 37, the third beam splitter 38, and the fourth reflector 39 are disposed on the second surface 12. The third reflector 35 is disposed corresponding to the fifth collimator 31, the first beam splitter 36 is disposed corresponding to the sixth collimator 32, the second beam splitter 37 is disposed corresponding to the steering unit, and the third beam splitter 38 is disposed corresponding to the steering unit. The third mirror 38 is correspondingly arranged with the seventh collimator 33, the fourth mirror 39 is correspondingly arranged with the eighth collimator 34, the third mirror 35 includes a third reflecting surface 351, the first beam splitter 36 includes a first beam splitting surface 361 and a first exiting surface 362, the second beam splitter 37 includes a second beam splitting surface 371 and a second exiting surface 372, the third beam splitter 38 includes a third beam splitting surface 381 and a third exiting surface 382, the fourth mirror 39 includes a fourth reflecting surface 391, the third reflecting surface 351 and the first beam splitting surface 361 are arranged opposite each other, the first beam splitting surface 361 and the second exiting surface 372 are arranged opposite each other, the second beam splitting surface 371 is arranged opposite to the steering unit 4, the third beam splitting surface 381 and the second beam splitting surface 371 are arranged opposite each other, and the fourth reflecting surface 391 and the third exiting surface 382 are arranged opposite each other.
[0042] The third beam, after being incident on the second beam-splitting surface 371 via the steering unit 4, is split into a first transmitted beam and a first reflected beam. The first transmitted beam enters the interior of the second beam-splitting element 37, exits from the second exit surface 372, and then enters the first beam-splitting surface 361. There, it is split into a second reflected beam and a second transmitted beam. The second reflected beam enters the third reflecting surface 351, and after reflection, exits via the fifth collimator 31. The second transmitted beam enters... The light is directed into the first beam splitter 36 and exits from the first exit surface 362, then exits through the sixth collimator 32. The first reflected light is incident on the third beam splitter 381, where it is split into a third reflected light and a third transmitted light. The third reflected light exits through the seventh collimator 33, and the third transmitted light is incident into the third beam splitter 38. After exiting from the third exit surface 382, it is incident on the fourth reflector 391, and after being reflected by the fourth reflector 391, it exits through the eighth collimator 34.
[0043] The beam splitting module 320 uses a third reflector 35, a first beam splitter 36, a second beam splitter 37, a third beam splitter 38, and a fourth reflector 39 to split the combined light into four collimators, which avoids fiber fusion splicing, reduces loss, ensures extinction ratio, and facilitates the integration of optical path systems, making the system compact and miniaturized.
[0044] The collimators of the N-input module 210 and the M-input output module 310 are both located at the end of the substrate 1 away from the turning unit 4, so that the splitter and combiner outputs fiber from one side, reducing the overall size. The fiber output from each collimator is protected by a loose tube.
[0045] Preferably, the beam splitting module 320 further includes a second polarization beam combiner / splitter 30, which is disposed on the second surface 12 between the second beam splitter 37 and the steering unit 4. The third beam combined light passes through the steering unit 4 and the second polarization beam combiner / splitter 30 in sequence and is then incident on the second beam splitting surface 371 to further improve the polarization degree of the third beam combined light and increase the extinction ratio.
[0046] The second polarization beam combiner / splitter 30 can adopt the same or similar structure as the first polarization beam combiner / splitter 20, which will not be described in detail here.
[0047] Preferably, the fifth collimator 31, the sixth collimator 32, the seventh collimator 33, and the eighth collimator 34 are all polarization-maintaining collimators to ensure that the polarization direction of the emitted light is aligned so that the extinction ratio is maximized.
[0048] Preferably, the beam combining unit 2 and the beam splitting unit 3 are symmetrically arranged about the substrate 1. The fifth collimator 31 corresponds to the first collimator 21, the sixth collimator 32 corresponds to the second collimator 22, the seventh collimator 33 corresponds to the third collimator 23, the eighth collimator 34 corresponds to the fourth collimator 24, the third reflector 35 corresponds to the first reflector 25, the first beam splitter 36 corresponds to the first beam combining unit 26, the second beam splitter 37 corresponds to the second beam combining unit 27, the third beam splitter 38 corresponds to the third beam combining unit 28, and the fourth reflector 39 corresponds to the second reflector 29.
[0049] Preferably, the first reflecting surface 251, the second reflecting surface 291, the third reflecting surface 351, and the fourth reflecting surface 391 are all 45-degree reflecting surfaces, and the light incident on each reflecting surface is reflected at 90 degrees before being emitted.
[0050] In practical applications, the first beam combiner 26, the second beam combiner 27, the third beam combiner 28, the first beam splitter 36, the second beam splitter 37, and the third beam splitter 38 can all be beam splitters to combine and split incident light of the same wavelength. At the same time, beam splitters with different splitting ratios can be selected as needed to solve the problem of fixed splitting ratio in existing beam splitters. The first beam combiner 26, the second beam combiner 27, the third beam combiner 28, the first beam splitter 36, the second beam splitter 37, and the third beam splitter 38 can also all be wavelength division multiplexing (WDM) plates to combine and split incident light of different wavelengths.
[0051] The steering unit 4 includes a steering prism 41. The third combined beam undergoes two 90-degree reflections within the steering prism 41 before being incident on the second beam-splitting surface 371. (See also...) Figure 10 , Figure 10 This is a schematic diagram of the structure of a steering prism 41 according to an embodiment of the present invention. The steering prism 41 includes an incident / exit surface 411, a first reflecting steering surface 412, and a second reflecting steering surface 413. The angle between the first reflecting steering surface 412 and the incident / exit surface 411 is 45 degrees, and the angle between the second reflecting steering surface 413 and the incident / exit surface 412 is 45 degrees. A third combined beam is perpendicularly incident on the incident / exit surface 411, then enters the steering prism 41, is reflected 90 degrees on the first reflecting steering surface 412, and then is incident on the second reflecting steering surface 413. After being reflected 90 degrees on the second reflecting steering surface 413, it is perpendicularly exited from the incident / exit surface 411.
[0052] Preferably, the cross section of the steering prism 41 along the direction perpendicular to the plane of symmetry of the bundle combining unit 2 and the bundle splitting unit 3 is an isosceles trapezoid, and the plane of symmetry of the bundle combining unit 2 and the bundle splitting unit 3 is coplanar with the plane of symmetry of the steering prism 41.
[0053] Please refer to the above. Figure 5 and Figure 6 , Figure 5This is a front structural diagram of a polarization beam splitter and combiner according to the fourth embodiment of the present invention. Figure 6 This is a schematic diagram of the reverse side structure of a polarization beam splitter and combiner according to a fourth embodiment of the present invention. In this embodiment, the polarization beam splitter and combiner has a 3-input, 5-output structure, where N is 3 and M is 5.
[0054] Please see Figure 5 The N-type input module 210 includes a first collimator 21', a second collimator 22', and a third collimator 23'. The beam combining module 220 includes a first reflector 24', a first beam combiner 25', a second beam combiner 26', and a second reflector 27'. The first collimator 21', the second collimator 22', and the third collimator 23' are sequentially disposed on the first surface 11 at one end away from the steering unit 4. The first reflector 24', the first beam combiner 25', the second beam combiner 26', and the second reflector 27' are all disposed on the first surface. The first reflector 24' is correspondingly arranged with the first collimator 21', the first beam combiner 25' is correspondingly arranged with the second collimator 22', the second beam combiner 26' is correspondingly arranged with the steering unit, and the second reflector 27' is correspondingly arranged with the third collimator 23'. The first reflector 24' includes a first reflecting surface 241', the first beam combiner 25' includes a first transmitting surface 251' and a first beam combining surface 252', the second beam combiner 26' includes a second transmitting surface 261' and a second beam combining surface 262', and the first reflector 27' includes a second reflecting surface 271'. The first reflecting surface 241' and the first beam combining surface 252' are arranged opposite to each other, the first beam combining surface 252' and the second transmitting surface 261' are arranged opposite to each other, the second reflecting surface 271' and the second beam combining surface 262' are arranged opposite to each other, and the second beam combining surface 262' is arranged opposite to the steering unit 4.
[0055] The first collimated light entering through the first collimator 21' is incident on the first reflecting surface 241', reflected on the first reflecting surface 241', and then incident on the first beam combining surface 252', where it is emitted. The second collimated light entering through the second collimator 22' is incident on the first projection surface 251', enters the interior of the first beam combining member 25', and then exits from the first beam combining surface 252', where it is collimated with the first collimated light emitted on the first beam combining surface 252'. The first beam is combined into a single beam. After the first beam is incident on the second transmission surface 261', it enters the interior of the second beam combiner 26' and then exits from the second beam combiner surface 262'. The third collimated beam, which enters through the third collimator 23', is incident on the second reflection surface 271'. After being reflected on the second reflection surface 271', it is incident on the second beam combiner surface 262'. After being emitted on the second beam combiner surface 262', it is combined with the exited first beam to form a second beam, which is then incident on the steering unit 4.
[0056] The beam combining module 220 uses a first reflector 24', a first beam combining component 25', a second beam combining component 26', and a second reflector 27' to combine the collimated light entering the three collimators, avoiding fiber splicing, reducing loss, ensuring extinction ratio, and facilitating the integration of the optical path system, making the system compact and miniaturized.
[0057] Preferably, the first collimator 21', the second collimator 22', and the third collimator 23' are all polarization-maintaining collimators, and the polarized light is transmitted along the slow axis of the optical fiber in the polarization-maintaining collimator.
[0058] Preferably, the beam combining module 220 further includes a first polarization beam combiner / splitter 20', which is disposed on the first surface 11 between the second beam combiner 26' and the steering unit 4. The second beam combined light is incident on the steering unit 4 through the first polarization beam combiner / splitter 20' to polarize the second beam combined light and improve the extinction ratio.
[0059] The first polarization beam combiner / splitter 20' can be adopted with... Figure 9 The same or similar structures will not be elaborated here.
[0060] Please see Figure 6The M-in / output module 310 includes a fourth collimator 31', a fifth collimator 32', a sixth collimator 33', a seventh collimator 34', and an eighth collimator 35'. The beam splitting module 320 includes a third reflector 36', a first beam splitter 37', a second beam splitter 38', a third beam splitter 39', a fourth beam splitter 310', and a fourth reflector 311'. The fourth collimator 31', fifth collimator 32', sixth collimator 33', seventh collimator 34', and eighth collimator 35' are sequentially disposed on the second surface 12 at one end away from the steering unit 4. The third reflector 36', first beam splitter 37', second beam splitter 38', third beam splitter 39', fourth beam splitter 310', and fourth reflector 311' are also present. The third reflector 36' is disposed on the second surface 12, corresponding to the fourth collimator 31'; the first beam splitter 37' is disposed to the fifth collimator 32'; the second beam splitter 38' is disposed to the sixth collimator 33'; the third beam splitter 39' is disposed to the steering unit 4; the fourth beam splitter 310' is disposed to the seventh collimator 34'; and the fourth reflector 311' is disposed to the eighth collimator 35'. The third reflector 36' includes a third reflecting surface 361'; the first beam splitter 37' includes a first beam splitting surface 371' and a first exiting surface 372'; the second beam splitter 38' includes a second beam splitting surface 381' and a second exiting surface 382'; the third beam splitter... The beam splitter 39' includes a third beam splitter 391' and a third exit surface 392', the fourth beam splitter 310' includes a fourth beam splitter 3101' and a fourth exit surface 3102', the fourth reflector 311' includes a fourth reflector 3111', the third emitting surface 361' and the first exit surface 372' are arranged opposite to each other, the first beam splitter 371' and the second beam splitter 381' are arranged opposite to each other, the second beam splitter 381' and the third exit surface 392' are arranged opposite to each other, the third beam splitter 391' and the steering unit 4 are arranged opposite to each other, the third beam splitter 391' and the fourth beam splitter 3101' are arranged opposite to each other, and the fourth exit surface 3102' and the fourth reflector 3111' are arranged opposite to each other.
[0061] The second combined beam, after being incident on the third beam-splitting surface 391' via the steering unit 4, is split into a first transmitted beam and a first reflected beam on the third beam-splitting surface 391'. The first transmitted beam enters the interior of the third beam-splitting element 39', exits from the third exit surface 392', and then enters the second beam-splitting surface 381'. On the second beam-splitting surface 381', it is split into a second reflected beam and a second transmitted beam. The second transmitted beam enters the interior of the second beam-splitting element 38', exits from the second exit surface 382', and then exits via the sixth collimator 33'. The second reflected beam enters the first beam-splitting surface 371', where it is split into a third transmitted beam and a third reflected beam. The third reflected beam passes through the sixth collimator 33'. The fifth collimator 32' emits a third transmitted light that enters the first beam splitter 37', exits from the first exit surface 372' and enters the third reflecting surface 361'. After being reflected by the third reflecting surface 361', it exits through the fourth collimator 33'. The first reflected light enters the fourth beam splitter 3101' and is split into a fourth transmitted light and a fourth reflected light. The fourth reflected light exits through the seventh collimator 34'. The fourth transmitted light enters the fourth beam splitter, exits from the fourth exit surface 3102' and enters the fourth reflecting surface 3111'. After being reflected by the fourth reflecting surface 3111', it exits through the eighth collimator 35'.
[0062] The beam splitting module 320 uses a third reflector 36', a first beam splitter 37', a second beam splitter 38', a third beam splitter 39', a fourth beam splitter 310', and a fourth reflector 311' to split the combined light into five collimators, which avoids fiber fusion splicing, reduces loss, ensures the extinction ratio, and facilitates the integration of the optical path system, making the system compact and miniaturized.
[0063] Preferably, the beam splitting module 320 further includes a second polarization beam combiner / splitter 30', which is disposed on the second surface 12 between the third beam splitter 39' and the steering unit 4. The second beam combined light passes through the steering unit 4 and the second polarization beam combiner / splitter 30' in sequence and is then incident on the third beam splitting surface 391' to further improve the polarization degree of the second beam combined light and increase the extinction ratio.
[0064] The second polarization beam combiner / splitter 30' can be adopted with... Figure 9 The same or similar structures will not be elaborated here.
[0065] Preferably, the fourth collimator 31', the fifth collimator 32', the sixth collimator 33', the seventh collimator 34', and the eighth collimator 35' are all polarization-maintaining collimators to align the polarization direction of the outgoing light and maximize the extinction ratio.
[0066] In practical applications, the first beam combiner 25', the second beam combiner 26', the first beam splitter 37', the second beam splitter 38', the third beam splitter 39', and the fourth beam splitter 310' can all be beam splitters, enabling them to combine and split incident light of the same wavelength. At the same time, beam splitters with different splitting ratios can be selected as needed to solve the problem of fixed reflection ratio in existing beam splitters. Alternatively, they can all be wavelength division multiplexers, enabling them to combine and split incident light of different wavelengths.
[0067] Please refer to the above. Figure 7 and Figure 8 , Figure 7 This is a front view of a polarization beam splitter and combiner according to the fifth embodiment of the present invention. Figure 8 This is a schematic diagram of the reverse structure of a polarization beam splitter and combiner according to a fifth embodiment of the present invention. In this embodiment, the polarization beam splitter and combiner has a 5-input, 3-output structure, where N is 5 and M is 3.
[0068] Please see Figure 7The N-type input module 210 includes a first collimator 21”, a second collimator 22”, a third collimator 23”, a fourth collimator 24”, and a fifth collimator 25”. The beam combining module 220 includes a first reflector 26”, a first beam combiner 27”, a second beam combiner 28”, a third beam combiner 29”, a fourth beam combiner 210”, and a second reflector 211”. The first collimator 21", the second collimator 22", the third collimator 23", the fourth collimator 24", and the fifth collimator 25" are sequentially disposed on the first surface 11 at the end away from the steering unit 4. The first reflector 26", the first bundler 27", the second bundler 28", the third bundler 29", the fourth bundler 210", and the second reflector 211" are disposed on the first surface 11. The first reflector 26" is disposed corresponding to the first collimator 21", the first bundler 27" is disposed corresponding to the second collimator 22", the second bundler 28" is disposed corresponding to the third collimator 23", the third bundler 29" is disposed corresponding to the steering unit 4, the fourth bundler 210" is disposed corresponding to the fourth collimator 24", and the second reflector 211" is disposed corresponding to the fifth collimator 25". The first reflector 26" includes a first reflecting surface 261". The bundle combiner 27” includes a first transmission surface 271” and a first bundle combiner surface 272”; the second bundle combiner 28” includes a second transmission surface 281” and a second bundle combiner surface 282”; the third bundle combiner 29” includes a third transmission surface 291” and a third bundle combiner surface 292”; the fourth bundle combiner 210” includes a fourth transmission surface 2101” and a fourth bundle combiner surface 2102”; the second reflector 211” includes a second reflective surface 2111”; the first reflective surface 261” and the first transmission surface 271” are arranged opposite to each other; the first bundle combiner surface 272” and the second bundle combiner surface 282” are arranged opposite to each other; the second bundle combiner surface 282” and the third transmission surface 291” are arranged opposite to each other; the third bundle combiner surface 292” and the steering unit 4 are arranged opposite to each other; the third bundle combiner surface 292” and the fourth bundle combiner surface 2102” are arranged opposite to each other; and the fourth transmission surface 2101” and the second reflective surface 2111” are arranged opposite to each other.
[0069] The first collimated light entering through the first collimator 21” is incident on the first reflecting surface 261”, reflected on the first reflecting surface 261”, and then incident on the first transmitting surface 271”, entering the interior of the first beam combiner 27”, and then exiting from the first beam combiner surface 272”; the second collimated light entering through the second collimator 22” is incident on the first beam combiner surface 272”, reflected on the first beam combiner surface 272”, and then combined with the exiting first collimated light to form a first beam combiner, which is then incident on the second beam combiner surface 282” and reflected there. The third collimated light entering through the third collimator 23” is incident on the second transmitting surface 281”, enters the interior of the second beam combiner 28”, and then exits from the second beam combiner surface 282”, combining with the first beam combiner reflected on the second beam combiner surface 282” to form a second beam combiner. The second beam is incident on the third transmission surface 291”, enters the interior of the third beam combiner 29”, and exits from the third beam combiner surface 292”. The fifth collimated beam, which enters through the fifth collimator 25”, is incident on the second reflection surface 2111”, is reflected on the second reflection surface 2111”, and then enters the fourth transmission surface 2101”, enters the interior of the fourth beam combiner 210”, and exits from the fourth beam combiner surface 2102”. The fourth collimated beam, which enters through the fourth collimator 24”, is incident on the fourth beam combiner surface 2102”, is reflected on the fourth beam combiner surface 2102”, and then combines with the exited fifth collimated beam to form a third beam combiner. The third beam combiner is incident on the third beam combiner surface 292”, is reflected on the third beam combiner surface 292”, and then combines with the exited second beam combiner to form a fourth beam combiner, which is then incident on the steering unit 4.
[0070] The beam combining module 220 uses a first reflector 26”, a first beam combining component 27”, a second beam combining component 28”, a third beam combining component 29”, a fourth beam combining component 210”, and a second reflector 211” to combine the collimated light entering the five collimators, avoiding fiber splicing, reducing loss, ensuring extinction ratio, and facilitating the integration of the optical path system, making the system compact and miniaturized.
[0071] The beam combining module 220 also includes a first polarization beam combiner / splitter 20". The first polarization beam combiner / splitter 20” is disposed on the first surface 11 between the third beam combiner 29” and the steering unit 4. The fourth beam combined light is incident on the steering unit 4 through the first polarization beam combiner / splitter 20”, so that the fourth beam combined light is polarized and the extinction ratio is improved.
[0072] The first polarization beam combiner / splitter 20” can be used with... Figure 9 The same or similar structures.
[0073] Please see Figure 8The M-in / output module 310 includes a sixth collimator 31", a seventh collimator 32", and an eighth collimator 33". The beam splitting module 320 includes a third reflector 34", a first beam splitter 35", a second beam splitter 36", and a fourth reflector 37". The sixth collimator 31", the seventh collimator 32", and the eighth collimator 33" are sequentially disposed on the second surface 12 at the end away from the steering unit 4. The third reflector 34", the first beam splitter 35", the second beam splitter 36", and the fourth reflector 37" are all disposed on the second surface 12. The reflector 34” is correspondingly set with the sixth collimator 31”, the first beam splitter 35” is correspondingly set with the seventh collimator 32”, the second beam splitter 36” is correspondingly set with the steering unit 4, and the fourth reflector 37” is correspondingly set with the eighth collimator 33”. The third reflector 34” includes a third reflecting surface 341”, the first beam splitter 35” includes a first beam splitting surface 351” and a first exiting surface 352”, the second beam splitter 36” includes a second beam splitting surface 361” and a second exiting surface 362”, and the fourth reflector 37” includes a fourth reflecting surface 371”. The third reflecting surface 341” and the first beam splitting surface 351” are arranged opposite each other, the first beam splitting surface 351” and the second exiting surface 362” are arranged opposite each other, the fourth reflecting surface 371” and the second beam splitting surface 361” are arranged opposite each other, and the second beam splitting surface 361” and the steering unit 4 are arranged opposite each other.
[0074] After the fourth beam is incident on the second beam splitting surface 361” via the steering unit 4, it is split into a first transmitted light and a first reflected light. The first reflected light is incident on the fourth reflecting surface 371”, and after being reflected by the fourth reflecting surface 371”, it is emitted through the eighth collimator 33”. The first transmitted light is incident inside the second beam splitter 36”, and after exiting from the second exit surface 362”, it is incident on the first beam splitting surface 351”. The first beam splitter 351” splits it into a second reflected light and a second transmitted light. The second transmitted light is incident inside the first beam splitter 35”, and after exiting from the first exit surface 352”, it is emitted through the seventh collimator 32”. The second reflected light is incident on the third reflecting surface 341”, and after being reflected by the third reflecting surface 341”, it is emitted through the sixth collimator 31”.
[0075] The beam splitting module 320 uses a third reflector 34”, a first beam splitter 35”, a second beam splitter 36” and a fourth reflector 37” to split the combined light and emit it from three collimators. This avoids fiber fusion splicing, reduces loss, ensures extinction ratio, and facilitates the integration of the optical path system, making the system compact and miniaturized.
[0076] The beam splitting module 320 also includes a second polarization beam combiner / splitter 30”. The second polarization beam combiner / splitter 30” is disposed on the second surface 12 between the second beam splitter 36” and the steering unit 4. The fourth beam combined light passes through the steering unit 4 and the second polarization beam combiner / splitter 30” in sequence and then enters the second beam splitting surface 361” to further improve the polarization degree of the fourth beam combined light and increase the extinction ratio.
[0077] The second polarization beam combiner / splitter 30” can be adopted with Figure 9 The same or similar structures will not be elaborated here.
[0078] In practical applications, the first beam combiner 27”, the second beam combiner 28”, the third beam combiner 29”, the fourth beam combiner 210”, the first beam splitter 35”, and the second beam splitter 36” can all be beam splitters, which can combine and split incident light of the same wavelength. At the same time, beam splitters with different splitting ratios can be selected as needed to solve the problem of fixed reflection ratio of existing beam splitters. Alternatively, they can all be wavelength division multiplexers, which can combine and split incident light of different wavelengths.
[0079] The polarization beam splitter and combiner can also be a 2-input, 2-output structure. In this case, the N-input module 210 includes a first collimator and a second collimator, and the beam combining module 220 includes a first reflector and a first beam combiner. The first reflector is correspondingly arranged with the first collimator, the first beam combiner is correspondingly arranged with the second collimator, and the first beam combiner is correspondingly arranged with the steering unit. The first collimated light entering through the first collimator is reflected at the first reflector and then enters the first beam combiner, where it is reflected at the first combining surface. The second collimated light entering through the second collimator enters the transmission surface of the first beam combiner, and after being transmitted and output from the first combining surface, it is combined with the reflected first collimated light to form the first combined beam incident on the steering unit 4. (See also...) Figure 3 Numbers 21, 22, 25, and 26 in the original text will not be illustrated here.
[0080] The M-in / output module 310 includes a third collimator and a fourth collimator. The beam splitting module 320 includes a second reflector and a first beam splitter. The second reflector is correspondingly arranged with the third collimator, and the first beam splitter is correspondingly arranged with the fourth collimator. The first beam splitter is correspondingly arranged with the steering unit. After the first combined beam is incident on the first beam splitter surface of the first beam splitter via the steering unit 4, it is split into a first transmitted beam and a first reflected beam. The first reflected beam is incident on the second reflector, and after being reflected by the second reflector, it is emitted through the third collimator. The first transmitted beam is incident inside the first beam splitter, and after exiting from the first exit surface of the first beam splitter, it is emitted through the fourth collimator. (See also...) Figure 4 The numbers 31, 32, 35, and 26 are not shown in the diagrams here.
[0081] The polarization beam splitter and combiner can also be a 2-input 3-output, 2-input 4-output, 2-input 5-output, 4-input 2-output, 4-input 3-output, 4-input 5-output, 3-input 2-output, 3-input 4-output, 5-input 2-output, 5-input 4-output, or other multi-input multi-output structures, as long as the beam combining module 220 can combine the N input beams into a combined beam that can be incident on the beam splitting module 320 through the steering unit 4 to split into M beams.
[0082] As can be seen from embodiments three, four, and five of the present invention, when N≥3, the N-input module includes N collimators, the beam combining module includes a first reflector, a second reflector, and N-1 beam combining elements. The first and second reflectors are respectively configured to correspond to the collimators located at both ends of the N collimators. N-2 of the N-1 beam combining elements are respectively configured to correspond to the N-2 collimators not located at both ends. One of the N-1 beam combining elements is configured to correspond to the steering unit 4. When M≥3, the M-input output module includes M collimators, the beam splitting module includes a third reflector, a fourth reflector, and M-1 beam splitting elements. The third and fourth reflectors are respectively configured to correspond to the collimators located at both ends of the M collimators. M-2 of the M-1 beam splitting elements are respectively configured to correspond to the M-2 collimators not located at both ends. One of the M-1 beam splitting elements is configured to correspond to the steering unit 4.
[0083] Of course, in addition to the method of the present invention, other beam combining and beam splitting structures can also be used, as long as they can achieve beam combining and beam splitting.
[0084] The present invention discloses a polarization beam splitter and combiner. By respectively setting the beam combining unit and the beam splitting unit on two surfaces of a substrate, and with the output end of the beam splitting unit and the incident end of the beam combining unit located on the same side of the substrate, a single-sided structure is adopted, which significantly reduces the volume of the beam splitter and combiner. By setting a steering unit at the edge of the substrate, the combined light after beam combining by the beam combining unit can be incident into the beam splitting unit for beam splitting. While keeping the volume of the beam splitter and combiner small, the normal operation of the beam splitter and combiner is ensured.
[0085] The present invention has been described by the above-described embodiments; however, these embodiments are merely examples for implementing the present invention. Furthermore, the technical features involved in the different embodiments of the present invention described above can be combined with each other as long as they do not conflict with each other. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention. On the contrary, any modifications and refinements made without departing from the spirit and scope of the present invention are within the scope of patent protection of the present invention.
Claims
1. A polarization beam splitter and combiner, characterized in that, The system includes a substrate, a beam combining unit, a beam splitting unit, and a steering unit. The substrate includes a first surface and a second surface disposed opposite to each other. The beam combining unit is disposed on the first surface, and the beam splitting unit is disposed on the second surface. The steering unit is disposed on one side of the substrate. The emitting end of the beam splitting unit and the incident end of the beam combining unit are both located on the other side of the substrate. The steering unit is disposed at the edge of the substrate. Neither the beam combining unit nor the beam splitting unit shares a surface area of the substrate with the steering unit. The beam combining unit includes a beam combining module, which includes a first polarization beam combiner / splitter. The beam splitting unit includes a beam splitting module, which includes a second polarization beam combiner / splitter. The beam combined by the beam combining unit is incident into the beam splitting unit via the steering unit for beam splitting.
2. The polarization beam splitter and combiner as described in claim 1, characterized in that, The beam combining unit includes an N-input module, and the beam splitting unit includes an M-output module, where M and N are both greater than or equal to 2. N input beams from the N-input module are incident on the beam combining module, and the combined beams from the beam combining module are incident on the beam splitting module via the steering unit. The M split beams from the beam splitting module are output via the M-output module.
3. A polarization beam splitter and combiner as described in claim 2, characterized in that, The N-type input module includes a first collimator, a second collimator, a third collimator, and a fourth collimator. The beam combining module includes a first reflector, a first beam combiner, a second beam combiner, a third beam combiner, and a second reflector. The first, second, third, and fourth collimators are sequentially disposed on the first surface at an end away from the steering unit. The first reflector, the first beam combiner, the second beam combiner, the third beam combiner, and the second reflector are all disposed on the first surface. The first reflector corresponds to the first collimator, the first beam combiner corresponds to the second collimator, and the second beam combiner corresponds to the steering unit. The third beam combiner is configured to correspond to the third collimator, and the second reflector is configured to correspond to the fourth collimator. The first reflector includes a first reflecting surface, the first beam combiner includes a first transmitting surface and a first beam combining surface, the second beam combiner includes a second transmitting surface and a second beam combining surface, the third beam combiner includes a third transmitting surface and a third beam combining surface, the second reflector includes a second reflecting surface, the first reflecting surface and the first beam combining surface are configured opposite to each other, the first beam combining surface and the second transmitting surface are configured opposite to each other, the second reflecting surface and the third transmitting surface are configured opposite to each other, the third beam combining surface and the second beam combining surface are configured opposite to each other, and the second beam combining surface and the steering unit are configured opposite to each other. The first collimated light, entering through the first collimator, is incident on the first reflecting surface, reflected thereafter entering the first combining surface, and reflected thereafter. The second collimated light, entering through the second collimator, is incident on the first transmitting surface, enters the interior of the first combining member, and exits from the first combining surface, where it combines with the first collimated light reflected from the first combining surface to form a first combined beam. The first combined beam is then incident on the second transmitting surface, enters the interior of the second combining member, and exits from the second combining surface. The fourth collimated light entering through the fourth collimator is incident on the second reflecting surface, and after being reflected on the second reflecting surface, it is incident on the third transmitting surface, enters the interior of the third beam combiner, and exits from the third beam combiner surface; the third collimated light entering through the third collimator is incident on the third beam combiner surface, and after being reflected on the third beam combiner surface, it combines with the exiting fourth collimated light to form a second beam combiner light; the second beam combiner light is incident on the second beam combiner surface, and after being reflected on the second beam combiner surface, it combines with the exiting first beam combiner light to form a third beam combiner light that is incident on the steering unit.
4. A polarization beam splitter and combiner as described in claim 3, characterized in that, The first polarization beam combiner / splitter is disposed on the first surface at a position between the second beam combiner and the steering unit, and the third beam combined is incident on the steering unit via the first polarization beam combiner / splitter.
5. A polarization beam splitter and combiner as described in claim 3, characterized in that, The M-in / output module includes a fifth collimator, a sixth collimator, a seventh collimator, and an eighth collimator. The beam splitting module includes a third reflector, a first beam splitter, a second beam splitter, a third beam splitter, and a fourth reflector. The fifth, sixth, seventh, and eighth collimators are sequentially disposed on the second surface at an end away from the steering unit. The third reflector, the first beam splitter, the second beam splitter, and the fourth reflector are disposed on the second surface. The third reflector corresponds to the fifth collimator, the first beam splitter corresponds to the sixth collimator, and the second beam splitter corresponds to the steering unit. The third beam splitter is configured corresponding to the seventh collimator, and the fourth reflector is configured corresponding to the eighth collimator. The third reflector includes a third reflecting surface. The first beam splitter includes a first beam splitting surface and a first exiting surface. The second beam splitter includes a second beam splitting surface and a second exiting surface. The third beam splitter includes a third beam splitting surface and a third exiting surface. The fourth reflector includes a fourth reflecting surface. The third reflecting surface and the first beam splitting surface are configured opposite to each other. The first beam splitting surface and the second exiting surface are configured opposite to each other. The second beam splitting surface is configured opposite to the steering unit. The third beam splitting surface and the second beam splitting surface are configured opposite to each other. The fourth reflecting surface and the third exiting surface are configured opposite to each other. Wherein, the third beam-combined light, after being incident on the second beam-splitting surface via the steering unit, is split into a first transmitted light and a first reflected light on the second beam-splitting surface; the first transmitted light is incident inside the second beam-splitting member, exits from the second exit surface, and then incident on the first beam-splitting surface, where it is split into a second reflected light and a second transmitted light; the second reflected light is incident on the third reflective surface, and after being reflected by the third reflective surface, it exits via the fifth collimator; the second transmitted light is incident inside the first beam-splitting member, exits from the first exit surface, and then exits via the sixth collimator; the first reflected light is incident on the third beam-splitting surface, where it is split into a third reflected light and a third transmitted light; the third reflected light exits via the seventh collimator; the third transmitted light is incident inside the third beam-splitting member, exits from the third exit surface, and then incident on the fourth reflective surface, where it is reflected by the fourth reflective surface, and then exits via the eighth collimator.
6. A polarization beam splitter and combiner as described in claim 5, characterized in that, The second polarization beam combiner is disposed on the second surface at a position between the second beam splitter and the steering unit. The third beam combines sequentially passes through the steering unit and the second polarization beam combiner before being incident on the second beam splitting surface.
7. A polarization beam splitter and combiner as described in claim 5, characterized in that, The steering unit includes a steering prism, and the third beam of light is incident on the second beam splitter after being reflected twice at 90 degrees within the steering prism.
8. A polarization beam splitter and combiner as described in claim 5, characterized in that, The beam combining unit and the beam splitting unit are symmetrically arranged about the substrate. The fifth collimator corresponds to the first collimator, the sixth collimator corresponds to the second collimator, the seventh collimator corresponds to the third collimator, the eighth collimator corresponds to the fourth collimator, the third reflector corresponds to the first reflector, the first beam splitter corresponds to the first beam combining unit, the second beam splitter corresponds to the second beam combining unit, the third beam splitter corresponds to the third beam combining unit, and the fourth reflector corresponds to the second reflector.
9. A polarization beam splitter and combiner as described in claim 5, characterized in that, The first beam combiner, the second beam combiner, the third beam combiner, the first beam splitter, the second beam splitter, and the third beam splitter are all beam splitters.
10. A polarization beam splitter and combiner as described in claim 5, characterized in that, The first reflective surface, the second reflective surface, the third reflective surface, and the fourth reflective surface are all 45-degree reflective surfaces.