TW500934B - Optical switch utilizing Faraday rotator - Google Patents

Abstract

An optical switch utilizing Faraday rotator includes a first receiving port, a second receiving port, a first output port, a second output port, a first beam splitter, a second beam splitter and a Faraday rotator. The first receiving port receives a first optical signal, and the second receiving port receives a second optical signal. The first beam splitter splits the first optical signal into a first polarization light and a second polarization light and splits the second optical signal into a third polarization light and a fourth polarization light. The second beam splitter combines the first polarization light with the second polarization light to form a first optical signal and combines the third polarization light with a fourth polarization light to form a second optical signal. Faraday rotator changes polarization direction of the first, second, third, and fourth polarization light. When the Faraday rotator is in a first rotation angle, the first optical signal synthesized by the second beam splitter outputs from the first output port while the second optical signal outputs from the second output port. When the Faraday rotator is in a second rotation angle, the first optical signal synthesized by the second beam splitter outputs from the second output port while the second optical signal outputs from the first output port.

Description

500934

[Field of the Invention] [Knowledge Technology] In optical systems, many cases need to perform signal or data generation. Therefore, optical switches play two important roles in optical communication systems. Among them, the most important function of the optical switch is the optical path of ^. In addition, the optical switch is set to a movable prism to switch the route of the optical signal. As shown in Figure 2A, in the 2 to 2 optical switch 4, one of the first light received by a first receiving end 41 is transmitted to a first output end 45 in the roaring number 43; at the same time, a second receiving end u A received second signal 44 is transmitted to a second output terminal 46. As shown in FIG. 1β, when the moving mechanism 47 provides power to move a beam 48 to an appropriate position, a first optical signal 43 received by a first receiving end 41 is transmitted after changing the route through the prism 48 and then transmitted. To the second output terminal 46; and one of the second signals 44 received by a second receiving terminal 42 changes the route through 稜鏡 48, and is transmitted to the first output terminal 45. It changes the travel path of the optical signal by moving the position of 稜鏡 48, that is, a 2 to 2 optical switch 4 is formed. [Summary of the Invention] As mentioned above, the object of the present invention is to provide a Faraday rotator.

V. Description of the invention (2) ^ ^ ^ The relationship ^ is to change the magnetic field applied to the Faraday rotator to change the polarization of the polarized light, and then control the course of the optical signal. For the purposes of the present invention, the present invention provides a light using a Faraday rotator. A dichroic beam splitter and a Faraday rotator and a daisy, a receiving end receives a first optical signal; a second receiving end Then, a beam splitter divides the first light signal into a first light, a second light signal, and a second light signal into a third polarized light and a polarized light. The second beam splitter sets the first polarized light and the second polarized light as the first optical signal, and the third polarized light and the fourth polarized light, and the first optical signal. The Faraday rotator is used to change the polarization direction of the first polarizer: vibrating light, second polarized light, and fourth polarized light. When the rotor is at the -first-rotation angle, the second beam splitter is synthesized from the first output end. The second optical signal is output from the second output terminal by the second synthesized first optical signal, and the third signal is output from the first output terminal. According to an embodiment of the present invention, the first beam splitter and the second beam splitter may use a polarized beam splitter (PBS, Polarized Beam SpHtter). The second and third polarized lights are p-polarized light 'and the second and fourth polarized f lights are S-polarized light. When the Faraday rotator is at the second rotation angle, ^ is enough to change the polarization direction of the light, so that the s-polarized light is converted into p-polarized light and the S-polarized light. Compared with the conventional technology, the present invention provides an optical switch using a Faraday rotator. If the magnetic field applied to the Faraday rotator is changed, it can be changed.

Fifth, the description of the invention (3) The rotation of the polarized light is not required to move, so that the position of the Faraday rotator can reduce the distance of the Faraday rotator to change the light signal, and it is not necessary to consider the Faraday rotator # The tolerance that occurs when moving. [Detailed description of the preferred embodiment]-A related drawing, which is illustrated with reference symbols, according to the present invention. Switching first 'refers to FIG. 2A and FIG. 2B for the same components. According to the preferred embodiment of the present invention, it includes a first receiving end 22, a second receiving end 23, a first d, and a second output end 25. , A first beam splitter u, a second = t a Faraday rotator 15. In 丨, the first-receiving end 22 receives _〇 (solid line part); the second receiving end 23 receives a second C dotted line part). The first optical splitter 11 divides the first optical signal 20 into a first-polarized second polarized light, and the second optical signal 21 into a third-polarized fourth-polarized light. The second beam splitter converts the first polarized light and the second into the first optical signal 20, and the third polarized light and the fourth into the second optical signal 21. The Faraday rotator 15 is used to change the polarization of the first, second, third, and fourth polarized lights. § The Faraday rotator 15 is at a first rotation angle, that is, the angle of the second beam splitter 12 The synthesized first optical signal 20 is output from the 24th, and the second optical signal 21 is output from the second output terminal 25. When the rotor 15 is at a second rotation angle, that is, when the angle is 90 degrees, the same optical switch 1 is used throughout the embodiment to split the beam splitter 1 2 a first light signal 21 vibrating light with a vibrating light and a polarized light Light is synthesized to polarized light. The degree is 0 degrees and the output end is the second Faraday beam splitter 500934. 5. Description of the invention (4) The first optical signal 20 synthesized by the device 12 is output from the second output terminal 25, and the second optical signal 21 is output by the first output. 24 output. The first beam splitter 11 and the second beam splitter 12 are respectively a first polarizing beam splitter 26 (Polarizing Beam

Splitter, PBS) and a second polarizing demultiplexer 27. This embodiment further includes a first reflection unit 13, a second reflection unit 14, a first collimator 16, a second collimator I ?, a third collimator 18, and a fourth collimator.器 19。 19. Among them, the first reflecting unit 13 and the second reflecting unit 14 are a first reflecting mirror surface 28 and a second reflecting mirror surface 29 respectively; in addition, the collimators convert the divergent light signals into parallel light signals. As shown in FIG. 2A, the first optical signal 20 enters the first polarization splitter 26 from the first receiving end 22, and the first optical signal 20 is separated into the first polarization splitter 26 by the first polarization splitter 26. Polarized light and second polarized light, where the first polarized light (p-polarized light 'P-polarization) passes directly through the first polarized demultiplexer 26, and the first polarized light (s-polarized light; s_polarizati) is reflected to Mirror surface 29. In FIG. 2A, the rotation angle of the Faraday rotator 15 is the first rotation angle. 1: The first polarized light and the second polarized light change the polarization direction by Faraday rotation = inverse, and the polarized light is reflected by the first reflection through the first reflection. In a polarization demultiplexer 27, the second polarized light also reaches the second polarization demultiplexer 27 after being radiated. The first-biased polarized demultiplexer 27 to the first-output terminal 24, * second 20, and the first-optical signal synthesized by the two beams at the first-terminal 24 ′ are output to the output terminal 24 of Tiandi. The first pre-signal 21 enters the first polarization demultiplexer 26 from the second receiving end 23

$ 8 pages ^ 34 V. Description of the invention (5) " '^ ^ 5 ^ A light signal 21 is separated into a third polarization first and a fourth polarization by the first polarization demultiplexer 26. Among them, the third polarization The light (P-polarized light) passes directly through the first polarization demultiplexer 26, and is reflected to the Faraday second by the second reflecting mirror surface 29, and the fourth polarized light (the polarized light) is reflected to the Faraday-turned fourth polarized light. It is reflected into the second polarization sub-wavelength 27 through the first reflecting mirror surface 28, and the third polarized light is reflected into the 27 through the second reflecting mirror surface 29. The third polarized light passes directly through the second polarized demultiplexer 25 = 5 'and the fourth polarized light is reflected to the second output end. Then, iii L two optical signals 21 are output from the second output terminal 25. Yuexiang ..., Fig. 2β, the first optical signal 20 enters the first polarizing demultiplexer 26 from the first receiving end, and the first light is connected to 4 and 22 to 26 are separated into first-polarized light and second-polarized light. : — = Waver

The polarized light) is reflected to the second reflection; D = 2. 6, and the second polarized light (S in Figure 2B, the rotation of the Faraday rotator 15 (90 degrees): Therefore, when passing through the Faraday rotator 15, the angle is second The rotation angle vibration light) is converted into S-polarized light, and the second polarization · first polarization light (P-polarized p-polarized light. The first-polarized ϋ polarization light) is converted into a mirror surface— "two-polarized demultiplexer m light) via the first One reflection and one polarization is Bozhai 27. Among them, the second polarization: the polarized light reaches the first and passes directly through the second polarization splitter 2: the second becomes P-polarized light) The light (converted into S-polarized light) is reverse-rounded out: 25, ❿ the first polarization to synthesize the first light signal 20, the first brother ;; the exit end 25, two beams

Tian Di output 25 output. I

JUU934 V. Description of the invention (6) The second optical signal 21 is invited by the second receiving end 23 into the first polarized demultiplexer 26, and the second optical signal 21 is separated into the third polarized light by the first polarized demultiplexer 26 The fourth polarized light, wherein the third polarized light (p-polarized light) passes through the first polarization directly into the wave device 2 6 'reflected into the Faraday rotator through the second reflecting mirror surface 29 and the fourth polarized light (s-polarized light) Reflected to the Faraday rotator 15, the Faraday rotator 15 converts the third polarized light into s-polarized light, and the fourth polarized light into P-polarized light. Then, the fourth polarized light (which has been converted into p-polarized light is reflected by the first reflecting mirror surface 28 to the second polarized demultiplexer 27, and the third polarized light (which has been converted into S-polarized light) also reaches the second polarization. Demultiplexer, 27. Among them, the fourth polarized light directly passes the second polarized demultiplexer π to the first $ out end 24 'and the third polarized light is reflected to the first output end 24, and the two beams are combined into the second light. The signal 21 is output by the first output terminal 24. Please refer to FIGS. 3A and 3B. In the second embodiment of the present invention, the first beam splitter 11 and the second beam splitter 12 are one of the trapezoidal shapes. The polarization demultiplexer 30 and the second polarization demultiplexer 31, and the first reflecting mirror surface 28 and the second reflecting mirror surface 29 in the first embodiment use a first reflection layer 32 and a second reflection layer, respectively. 3 3 Instead, the remaining components and features in this embodiment are the same as those in the first embodiment. The first reflective layer 32 and the second reflective layer 33 are respectively disposed on a surface 36 and a first surface of the first polarization demultiplexer 30. On one surface 37 of the two-polarization demultiplexer 31, its surface 36 and surface 37 are respectively connected to a polarization furnace film (p〇iarize (j filter) 38 and a polarization filter film 39 are parallel to each other. The functions of the first reflection layer 32 and the second reflection layer 33 are the same as those of the first reflection mirror surface 28 and the second reflection mirror surface 29 in the first embodiment, and the first reflection layer 32 is changed. The travel path of the second polarized light and the third polarized light, and the second reflective layer 33 changes the first polarized light and

Page 10, 500934 V. Description of the invention (Ό Route of the fourth polarized light. Please refer to FIGS. 4A and 4B again. In the third embodiment of the present invention, the first polarization splitter 2 in the first embodiment 6 and the second polarization splitter 27 are replaced by a first polarization layer 34 and a second polarization layer 35, respectively, and the remaining components and features are the same as those of the second embodiment. The first polarization layer The functions of 34 and the second polarizing layer 35 are the same as those of the first polarizing demultiplexer 26 and the second polarizing demultiplexer 27. The optical signal is divided into P-polarized light and S-polarized light, and the polarized light is synthesized into Optical signals, the polarizing layers are respectively disposed on a sheet-like substrate having a high light transmittance; and the first reflective layer 32 and the second reflective layer 33 are also disposed on a sheet-like base having a high light transmittance Here, the sheet-like substrate with high light transmittance can be a thin sheet, which is used to fix the polarizing layers and the reflective layers. The light-open relationship using the Faraday rotator provided by the present invention can be changed. The magnetic field applied to the Faraday rotator 15 is used to switch the route of the optical signal. The first receiving end 22, the second receiving end 23, One output end 24, two output ends 25, and Faraday rotator 15 are all fixed to one: The application of the Faraday rotator provided by the invention ^ = Therefore, this terminal and the Faraday rotator 15 are considered; ^ Only $ ^ is considered when changing during assembly The tolerance due to movement. A, without the need to cut the optical switch of the Faraday rotator, there is no need to test the alignment between the receiving end and the output end. The description is only exemplary and more accurate. The spirit and scope of the present invention, but the basin: restrictive. Any equivalent modification or change that does not depart from the scope of the appended patent application is 500934. Brief description [Simplified description of the drawings] Figures 1A and 1B are schematic diagrams illustrating a conventional 2 to 2 optical switch. Figures 2A and 2B are schematic diagrams illustrating a light switch using a Faraday rotator in the first embodiment of the present invention. 3A and 3B are schematic diagrams illustrating an optical switch using a Faraday rotator in a second embodiment of the present invention. FIGS. 4A and 4B are schematic diagrams illustrating an optical switch using a Faraday rotator in a third embodiment of the present invention.

[Illustration of Symbols] 1 Use of Faraday Rotor Light Switch 11 First Beamsplitter 12 Second Beamsplitter 13 First Reflection Unit 14 Second Reflection Unit 15 Faraday Rotor 16 First Collimator 17 Second Collimator 18 Three collimators 19 Fourth collimator 20 First optical signal 21 Second optical signal 22 First receiving end 23 Second receiving end

Page 12 500934 Brief description of the diagram 24 First output end 25 Second output end 26 First polarizing demultiplexer 27 Second polarizing demultiplexer 28 First reflecting mirror surface 29 Second reflecting mirror surface 30 First polarizing branch Filter 31 second polarized splitter 32 first reflective layer 33 second reflective layer 34 first polarized layer 35 second polarized layers 36, 37 surfaces 38 to 39 polarized filter film 4 optical switch 41 first reception Terminal 42 苐 Receiving terminal 43 First light signal 44 Second signal 45 First output terminal 46 Second output terminal 47 Actuating mechanism 48 稜鏡

Page 13

Claims (1)

Six, tm 901281R1 patent application scope of an application method and the first quarter of the second and then the first round of the second round and the second round of the first lose the second polarization of the fourth polarization of the second polarization of the first light into the The second first Faraday light and the third when the two optical signals synthesized by the optical device are twisted when the two optical signals synthesized by the optical device are twisted at the first receiving end and the outgoing end of the optical device; The rotor polarized fara ’s light switch includes the ·· which receives a first optical signal; it receives a second optical signal; 'It divides a first optical signal into one and A second optical signal is divided into-, which will, and the number; so that its energy and the first polarization will be third enough to change the fourth polarized light. The second rotor is in a first first light. The signal is output from the second output terminal, and the second rotor is in a second first optical signal and is output from the first output terminal. In the year W and b, the polarization direction of light and reading light and the first polarized light is the rotation angle. The first round out, the rotation angle, the second round out, and the M-end turn out. When ^, the second end output, the 2 • The light switch using the Faraday rotator according to item 1 of the scope of the patent application, wherein the first polarized light and the third polarized light are p-polarized light, and the first polarized light and the fourth polarized light are S-polarized light. . Page 14_Case No. 9012Siy VI. Scope of Patent Application " " " '—I-day amendment ~ 3 · If the scope of patent application is No.] Off, use the light of the Faraday rotator described in the above to open the first beam splitter And Polarized Beam Spli ^ t * The optical splitter is a polarized beam splitter (PBs, ΐ Θ Γ) 〇4. As described in the patent application scope No. 丨 ^, where the Faraday rotator's light is used to open the splitters It is bonded on a sheet-like substrate. It is set on a light switch with a high light transmittance, such as the third item of the scope of patent application, the third item of the rotor, and further includes the use method described in one of the four items to resist a first reflection unit and two-one polarized light. The second polarized light = reflecting unit is used to change the travel path so that the first, the third polarized light and the fourth polarized light ^ the vibrating light and the fourth polarized light = the vibrating light, the first Two polarized lights, the first value optical device. The first-to. 3 6 · According to the fifth aspect of the scope of patent application, wherein the light using the Faraday rotator described in the negative is turned on, the first reflection unit and the 哕 / Zhuoyi reflection unit are reflective mirror surfaces. 7 · If the scope of the patent application is closed, the light of the Faraday rotator described in ^ is turned on. Page 15 500934 Correction element No. 90128161 The reflecting unit is a reflecting layer, which respectively covers the sixth and patent application scopes of the first reflecting unit and ... 溆 one surface of the second polarization splitter is set to the first polarization Detector Boundary ^ 0 0 ^ < Said use of Faraday rotator light on 8. As in the scope of the patent application No. 5 customer, where # # the first reflection unit and the second reflection unit are reflective layers ', ... are placed on the sheet-like substrate with high light transmittance. 9 · The light switch using the Faraday rotator according to item 1 of the scope of patent application, further comprising: four collimators, a receiver, the first output number and the second optical signal It is respectively arranged at the first receiving end, the second connecting end and the second output end to collimate the first optical signal. 10 As described in the first level of the patent scope, where the Faraday rotator is used The light that drives the Faraday rotator is 0 degrees and 90 degrees. Λ A rotation angle is separated from the second rotation angle Page 16