• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
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    • 专利摘要:
    A method, apparatus, and system of steering a light beam having a arbitrary polarization into a specified location by a series of optical elements whose synchronous operation in determining the amount of deflection is insensitive to the light beam's polarization, in which the polarization-insensitive beam-steering device including at least one component which is an electrooptic component. The device deflects a light beam propagating through the device in an amount proportional to a voltage applied to the device.
    公开号:CA2324707A1
    申请号:C2324707
    申请日:2000-10-27
    公开日:2001-04-29
    发明作者:Valentine N. Morozov
    申请人:Lumentum Ottawa Inc；
    IPC主号:G02F1-29
    专利说明:
    ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent FIELD OF THE INVENTIONThis invention generally relates to an electrooptic device which routes and deflects a light beam propagating through the device. More particularly this invention relates to a polarization and wavelength insensitive electrooptic beam-routing device. BACKGROUND OF THE INVENTIONFor many applications of fiber optics, the transmission of optical signals involves switching and routing of the optical signals between different fibers. To route a light ray to a particular fiber, a change is made to the direction or angle in which the light ray is travelling, ~o when switching or routing is performed in free space. Figure 1 illustrates a side view of a light ray deflecting through a prism 10. The prism 10 has an apex angle a and refractive index of 1+ 8n. The prism 10 deflects the light ray propagating through the prism 10 by an angle of ~3.Figures 2 and 3 depict an electrooptic prism 12 consisting of many prisms and each of is them consisting of four antiparallel ferroelectric domain regions 14 and 16. The electrooptic prism 12 also has a pair of continuous electrodes 18. Supplying voltage to the continuous electrodes 18 causes a spatially uniform electric field to be applied to the electrooptic prism 12 including the light transmissive portion of the ferroelectric regions 14 and 16. The electric field changes the refractive index of the prism 12, thereby inducing an electronically-2o controllable deflection to a light beam propagating through the electrooptic prism 12. This electronically-controllable deflection of the light beam allows steering of the light beam to occur.However, an incoming incident light beam having a random polarization deflects into two distinct locations based on the polarization of the input light beam. In paraxial 2s approximation, the deflection angle, [3, is approximated by the equation of ~3 ~ 8n a. Thus, (3 is approximate to the index of refraction, 8n, for the material through which the light beam propagates multiplied by the apex angle, a, of the device through which the light beam propagates. The prism 12 is made up of material such as LiNb03, LiTa03, or similar electrooptic crystal lacking a center of symmetry. When an electrical field is applied across a 3o LiNb03 crystal, the index ellipsoid changes resulting in the indices of refraction to change for _ ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent the two orthogonal linear polarizations. Thus, the propagating light encounters two different refractive indices for the two orthogonal polarization waves. Therefore, the deflection angles for the two different polarization waves will be different. For example, for Z-cut LiNb03 y-propagating crystal, the ratio between the two electrooptic coefficients (refractive indices) for the transverse magnetic (TM) and transverse electric (TE) polarizations is r33/r3~ ~ 3. The deflection angles may be represented by the following equations:~TM ~ cSnTM a ~TE ,: $nTE a.The angle of deflection for the transverse magnetic wave, (3TM, is approximate to the index of refraction of the transverse magnetic wave for the chosen material, BnTM, multiplied io by the apex angle, a, of the device through which the light beam propagates. Similarly, the angle of deflection for the transverse electric wave, (3TE, is approximate to the index of refraction of the transverse electric wave for the chosen material, BnTE, multiplied by the apex angle, a, of the device through which the light beam propagates.Thus, for LiNb03, the angle of deflection for the TM wave, (3TM, is approximately is three times the angle of deflection for the TE wave, (3TE. The difference in magnitude of deflection causes an incoming incident light beam having random polarization to be deflected into different locations for each polarization. Cross-talk between signal channels may occur due to the inaccuracies caused by the TM and TE polarization waves of a light beam. Cross-talk means any undesired signal leakage from one channel into another channel. Generally, 2o the optical switching techniques used in the prior art suffer from poor cross-talk but some alternative approaches exist to eliminate this problem.Some prior art optical switches add additional components to ensure the entire light signal will be polarized as a TM or TE wave. After polarizing the light signal, the switches activate polarization-rotators within the switch to route the light signal. These switches use Zs the difference in the deflection angles that a TM wave and TE wave experience while propagating though a material, as previously described for LiNb03, to route the signal to a first location corresponding to the TE deflection angle or to a second location corresponding to the TM deflection angle. However, this approach causes at least two problems. These switches have a discrete adjustment capability to route the light beam to either the first or 3o second location but lack a fine control to route the light beam to any given number of ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent locations. Furthermore, a decrease occurs in the usable density of fibers in a given area because of the requirement of two output connections for every one input.Some other prior art optical switches attenuate the light signal by blocking either the TM or TE wave to control the placement of the light signal. However, switches using this technique necessitate later amplification of the light signal to account for the attenuation of the light signal. What is needed is switch that provides polarization-independence and improved control over the routing of a routed light beam. The present invention seeks to overcome one or more of the limitations of the prior art optical switching devices. SUMMARY OF THE INVENTIONA method, apparatus, and system for steering a light beam is described. In one embodiment, a method includes receiving a light beam, where the light beam propagates through a series of optical elements. At least one of the series of optical elements has a different indices of refraction for the transverse electric polarization and the transverse ~s magnetic polarization. The method also includes deflecting the light beam into a specified location by the series of optical elements whose synchronized operation in determining the amount of deflection is insensitive to the light beam's polarization. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood more fully from the detailed 2o description given below and from the accompanying drawings of various embodiments of the invention, which, however, should not be taken to limit the invention to the specific embodiments, but are for explanation and understanding only.zs FIGURE 1 is a side view of a light ray deflecting through a prior art prism;FIGURE 2 is a perspective view of a prior art electrooptic prism with a pair of continuous electrodes attached; FIGURE 3 is an exploded view of the prior art electrooptic prism of FIG. 2;FIGURE 4 is a side view of a general scheme for polarization-insensitive angular beam 3o steering with two identical electrooptical prisms and a half wave plate;
    - ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent FIGURE 5 is a block diagram of an embodiment of the polarization-insensitive beam-steering device;FIGURE 6 is a block diagram of another embodiment of the polarization-insensitive beam-steering device;s FIGURE 7 is block diagram of an embodiment of a 4x4 optical switch; FIGURE 8 is a block diagram of an embodiment of a 1x4 optical switch;FIGURE 9 is a diagram of the beam-steering device directing an exiting ray of light to a particular portion of on a segmented mirror;FIGURE 10 is a block diagram of an embodiment of a 1 x3 optical switch in a "cross-shaped"~o configuration;FIGURE 11 is a block diagram of an embodiment of a 1 x3 optical switch in an "in-line"configuration;FIGURE 12 is a block diagram of an embodiment of a 1 x4 optical switch using a Fourier lens;is FIGURE 13 is a block diagram of an embodiment of a 1xN optical switch; and FIGURE 14 is a block diagram of an embodiment of a NxN optical switch. DETAILED DISCUSSIONA method and apparatus for performing polarization and wavelength insensitive beam steering is described. In the following description, numerous details are set forth. It will be 2o apparent, however, to one skilled in the art, that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form, rather than in detail, in order to avoid obscuring the present invention.Figure 4 is a block diagram of one embodiment of a polarization-insensitive beam-is steering device. Referring to Figure 4, polarization-insensitive beam-steering is achieved by using a combination of two electrooptic devices, such as prisms 12 and 22, and a polarization rotator 20, such as a half wave plate, located between the two prisms 12 and 22. In one embodiment, the polarization rotator 20 is located symmetrically between the two prisms 12 and 22. A light beam possessing an arbitrary polarization is routed into two angular directions 3o by the first prism 12. The angular beam routing can be represented by:
    ,. ', , , , CA 02324707 2000-10-27 Doc. No. P 023 CA Patent I TM ~ SnTM a ~ I TE ~ bnTE a Each of the TE and TM orthogonal polarization waves of the light beam are deflected by different amounts. After being deflected by the first prism 12, the TM wave and the TEs wave pass through a polarization rotator 20. The polarization rotator 20 rotates the plane of polarization by 90 degrees. Thus, the TE wave transforms into a TM wave, and the TM wave transformed into a TE wave. These two waves propagate through the second electrooptic prism 22, which is substantially identical in the applied electric field and material characteristics of the first prism 12. The deflection angles for the TM and TE waves in the to second prism 22 can be represented by:~2TM ~ SnTM a ~2TE ~ SnTE a As a result, each wave regardless of its initial polarization experiences the same amount of angular shift. The total angular shift of the light beam is: Is (3tota~ ~ OnTM ~- cSnTE~ a With this approximation for (3tocah the electrooptic polarization-insensitive beam-steering device deflects an input light beam into the same angular shift regardless of the state of polarization of the incident beam. Furthermore, in small angle paraxial approximation, the 2o angle of deflection is approximately independent of the incidence angle of a light beam. Thus, the polarization-insensitive beam-steering device allows an optical system using birefringent electrooptic crystals to manipulate any incoming light beam regardless of the angle of incidence for the beam or polarization of the beam.The operation and construction of the polarization rotator 20 and prisms 12 and 22 2s described in detail above will be similar to the corresponding components in the embodiments that follow.Figure 5 is a block diagram of an embodiment of the polarization-insensitive beam-steering device 100. Referring to Figure 5, an input 102 optically couples a light ray possessing a random polarization to a collimator 104 or other similar device. The collimator 30 104 collimates the light and passes the light through to the first electrooptic prism array 106. ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent The first electrooptic prism array 106 deflects the propagating light according to the voltage applied to the continuous electrodes. The electric field generated by the applied voltage intersects the light transmissive portion of the ferroelectric regions of the electrooptic prism array 106 to steer the light beam. The TE polarization and the TM polarization will be steered s to different angles as a result of the different electrooptic coefficients corresponding to the TEwave and the TM wave.The two orthogonally polarized waves pass through a polarization rotator 108. In one embodiment, the polarization rotator 108 comprises a half wave plate. In one embodiment, the polarization rotator 108 rotates the polarization of the two waves by 90 degrees. Thus, the io polarization rotator 108 transforms the TE wave into a TM wave and transforms the TM wave into a TE wave. The polarization rotator 108 is located substantially symmetrically between the first electrooptic prism array 106 and a second electrooptic prism array 110.After exiting the polarization rotator 108, the waves propagate through a second prism array 110. The second prism array 110 has substantially the same voltage applied as the first Is prism array 106. Thus, the rotated TM and TE waves intersecting with the applied electric field of the second prism array 110 experience the same complementary beam deflection as the original TM and TE waves experienced. The resulting overall deflection angle for the input TM and TE waves will be the same. The overall deflection of the light beam exiting the second prism array 110 is (3tQ~ai ~ (BnTM + BnTE) a, with the total amount of the deflection being 2o proportional to the voltage applied the prism arrays 106 and 110. The light beam from the second electrooptic prism array 110 propagates to focusing optics 112, which may comprise one or more wavelength-routing devices. The selection of the one or more wavelength-routing devices varies depending upon the particular application of the polarization-insensitive beam-steering device.2s Figure 6 is another embodiment of the electrooptic polarization-insensitive beam-steering device 200. Referring to Figure 6, a collimator 204 receives the input light beam from an input 202. The collimator 204 expands the light beam and passes the beam to a walkoff crystal 206 or other such beam spatial-orientation device. In one embodiment, the walkoff crystal 206 comprises a calcite crystal. The walkoff crystal 206 separates in space the 3o two orthogonally-polarized beams. One of the beams (first beam) passes through a half wave ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent plate 208. The other beam (second beam) passes through a blank piece of glass 210, or other optically-transparent device, which does not change the beam's polarization. Both beams now possess the same state of polarization, such as, for example, a TE polarization as shown in Figure 6. The two beams with identical polarizations enter two separate channels of an s electrooptic beam-steering device 212. Because both beams have the same polarization, the two beams experience the same amount of deflection which is proportional to voltage applied to the electrooptic device.Several embodiments exist to implement the two channel beam-steering device 212.One embodiment places two identical electrooptic plates 214 and 216 in parallel to each other.io In one embodiment, both of the electrooptic plates have the same voltage applied to their respective electrodes. This embodiment is shown in Figure 6. As a second embodiment, the two electrooptic plates can be located in one plane with both plates experiencing the same uniform electric field applied.After the beams pass through the two-channel electrooptic beam-steering device 212, is one of the beams (first beam) travels through a 90 degree polarization rotator 218 and the other beam (second beam) propagates through an optically-transparent device 220. This causes the two beams, still separated in space, to have the same state of the polarization as the input beam possessed after passing through the first walkoff crystal 206. The second walkoff crystal 222 combines the two spatially separated beams into one beam with a polarization 2o identical to polarization of input beam entering the collimator 204. Overall, the light beam propagating from the input 202 to the second walkoff crystal 222 deflects by an amount proportional to the voltage level applied to the two channel beam-steering device 212. One or more wavelength-routing devices receive the light beam exiting from the second walkoff crystal 222, and focusing optics 224 is used to derive multiple light beams to appropriate 2s output fiber.The focusing optics of the second stage of the polarization-insensitive beam-steering device may comprise one or more wavelength-routing devices, the exact composition of which depends upon the particular application of the device.Figure 7 is block diagram of a NxN switch using the polarization-insensitive beam-3o steering device 400. Referring to Figure 7, the switch includes an input plane and an output ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent plane. The input plane comprises a polarization-insensitive beam-steering device similar to the embodiment depicted in Figure 5. Specifically, in one embodiment, the input plane comprises four sets of similar beam-steering devices 303, 304, 305, and 306, one for each input fiber. In one embodiment, each of beam steering devices 303-306 comprise two s electrooptic (E/O) prisms with a half wave plate installed between the two identical E/Oprisms. Alternatively, the input plane may comprise the input plane shown in Figure 6. The output plane comprises one or more wavelength-routing devices 302. The one or more wavelength-routing devices 302 comprise the components in the output plane which couple and/or manipulate the light beam transmitted from the input plane.io As depicted in Figure 7, a light beam exiting a given input-plane electrooptic prism, such as prism 308, can be directed across the free space to the input of any of the four beam-steering devices 310, 311, 312, and 313 in the output plane. The voltage applied to the prisms in the input-plane controls the deflection of the light beam, which in turn directs the light beam to the input of a particular electrooptic prism in the output plane. Thus, the function of is the overall deflection occurring in the input plane is to direct the beam at a given angle to a specific output prism.In the output plane, the function of the overall deflection occurring in the output plane changes the angle of the beam propagating from the input-plane to efficiently couple the beam to a particular output. In the output plane, the light beam from the input plane then enters a 2o prism, such as prism 316, at a given angle depending upon which input plane device directed the light beam. The light beam propagates through prism 316 and deflects in proportion to the electric field applied to prism 316. To accomplish lossless switching between the input beam position and the output beam position, the same driving voltage is applied to the E/O prisms array in input and output planes. The first prism 316 couples the light beam to a polarization 2s rotator 318 located symmetrically between the two electrooptic devices 316 and 320 in the output plane. The polarization rotator 318 rotates the two orthogonal polarization waves by 90 degrees. The two orthogonal polarization waves receive the same overall deflection when the two orthogonal waves intersect the electric field from second electrooptic device 320.Thus, any light beam routed from the input 301 to the output 324 is effectively steered twice.3o The first steering occurs in the input plane to direct the beam to a specific output prism. The ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent second steering occurs in output plane to align the light beam to efficiently couple to a collimator 322. The collimator 322 couples the light beam to an optical fiber 326 at output 324. Additional optics may be installed between input and output planes to compensate for beam divergence. Figure 8 is block diagram of a 1 x4 broad band switch using the polarization-insensitive beam-steering device 400. Referring to Figure 8, the switch includes an input plane and an output plane. The input plane comprises a polarization-insensitive beam-steering device similar to the embodiment depicted in Figure 5. Specifically, the input plane comprises a collimator 402 which passes an input light ray to two electrooptic (E/O) prisms io with a half wave plate 406 installed between the two identical E/O prism arrays 404 and 408.The output plane comprises one or more wavelength-routing devices 410. The one or more light beam routing devices 410 comprise the components in the output plane which couple and/or manipulate the light beam transmitted from the input plane.As depicted in Figure 8, a light beam exiting the second electrooptic prism 408 can be is directed at a given angle across the free space to a segmented mirror 412 communicatively connected to the second electrooptic prism 408. The particular mirror segment directs the light beam to an associated walkoff crystal, such as walkoff crystal 414. In one embodiment, the walkoff crystal 414 has a small adjustment range (e.g., approximately 1 to 1.5 mm in one embodiment) to help focus and direct the light ray from the mirror segment to enter the zo collimator 416. Adjustment may be needed because TE and TM waves emerging from E/Oprism 408 propagate in the same direction but slightly shifted spatially. The collimator 416 couples the light beam to an optical fiber 420 through an output 418.Figure 9 illustrates that a single segmented mirror 412 may be used instead of multiple separate mirrors for directing the light beam to an associated walkoff crystal.is Figures 10 and 11 illustrate alternative embodiments of a 1 x3 switch using the polarization-insensitive beam-steering device 500. Referring to Figure 10, a light beam exiting the second electrooptic (E/O) prism 502 can be directed at a given angle across the free space to a segmented mirror 504. One of the mirror segments directs the light beam to an associated walkoff crystal, such as walkoff crystal 506. In one embodiment, the walkoff 3o crystal 506 has a small adjustment range (e.g., approximately 1-1.5 mm) to help focus and Doc. No. P 023 CA Patent direct the reflected light ray from the mirror segment to enter the collimator 508. The collimator 508 couples the light beam to an optical fiber 512 through an output 510. As shown in Figures 10 & 11, the outputs may be arranged in a number of configurations such as a "cross-shaped" configuration shown in Figure 10 or an "in-line" configuration as shown in s Figure 11.Referring to Figure 11, the light beam from the input plane is deflected by a series of mirrors 514 twice to route the beam to a particular walkoff crystal. The walkoff crystal, such as walkoff crystal 516, has small adjustment range to focus and direct the light beam to collimator 518. The collimator 518 couples the light beam to an optical fiber 522 through an io output 520. Additionally, the light exiting the second electrooptic prism 502 may be directed across free-space to a collimator 524 that is aligned in-line with the second electrooptic prism 502. The in-line alignment alleviates the need for an adjustment plate such as the walkoff.The collimator 524 couples the light beam to an optical fiber 526 through an output 528.Figure 12 is a block diagram of one embodiment of a 1x4 broad band switch using the is polarization-insensitive beam-steering device 600. Referring to Figure 12, a light beam exiting the second electrooptic prism 602 can be directed at a given angle to a Fourier lens 604 communicatively coupled to the second electrooptic device 602. The light beam propagates approximately one focal length and strikes the Fourier lens 604 at a given angle of incidence. The Fourier lens 604 causes the exiting light beam's angle of refraction to be 2o deflected and directed to a particular plane micro lens, such as plane micro lens 606. The Fourier lens 604 also reduces the effects of chromatic aberration by focusing two wavelengths of light on the same plane. The plane micro lens 606 receives the light beam and focuses the light onto a walkoff crystal 608. The walkoff crystal 608 acts as an adjustment plate with a range to direct and couple the light beam into an output 612. The light beam propagates 2s through the output 612 to fibers such as thermally-diffused expanded core (TEC) fibers 610 or standard single or multi mode fiber. In one embodiment, F=3.2 cm, waisto"~ = 200mm, waist;n = 80~n, PML diameter = 250~n, PML spacing = 250mm.Figure 13 is a block diagram of one embodiment of a 1xN broad band switch using the polarization-insensitive beam-steering device 700. Referring to Figure 13, a light beam so exiting the second electrooptic prism 702 may be directed at a given angle to a particular ', CA 02324707 2000-10-27 Doc. No. P 023 CA Patent optical element such as computer generated hologram (CGH) 704. The CGH 704 focuses and deflects eight beam for coupling to the optical fibers 710. The CGH 704 routs the light beam to a walkoff crystal 706. The walkoff crystal 706 acts as an adjustment plate to direct and couple the light beam into an output 708. The light beam travels through the output 708 to the s fibers 710 in V-groves. Figure 14 is a block diagram of one embodiment of a NxN switch using the polarization-insensitive beam-steering device 800. An input 802 couples a light beam with an arbitrary polarization to a series of lenslet arrays 804. Each lenslet array, such as array 806, is a plurality of identical small aperture lenslets. The lenslet array allows an increased level of io control over the light spot size. The lenslet array 806 reduces the diameter of the light beam and directs the input light beam into an electrooptic prism, such as electrooptic prism 808.The prism 808 is one of two electrooptic (E/O) prisms with a half wave plate 810 installed symmetrically between the two identical E/O prisms array 808 and 812. The voltage applied to the prisms 808 and 812 controls the deflection of the light beam to a particular spot on the is Fourier lens 814. The Fourier lens 814 causes the angle of refraction for the light beam exiting the lens 814 to be deflected and focused to a particular electrooptic prism, such as electrooptic prism 816. The Fourier lens 814 also reduces the effects of chromatic aberration by focusing two wavelengths of light on the same plane. The light ray propagates through the first electrooptic prism 816, then half wave plate 818, and then through the second 2o electrooptic prism 820. The voltage applied to the prisms 816 and 820 controls the deflection of the light beam to a lenslet array, such as array 822. The lenslet array 822 reduces the diameter of the light beam and directs the input light beam into an output 824. The use of the lenslet array further improves the control over the placement and size of the routed light beam to allow an increase in the density of optic fibers per given area. The light beam travels 2s through the output 824 to an optical fiber 826.Thus, a series of optical elements have been described in which the optical elements are located between the input and output ports to define a light path that can be altered to couple a selected output to a selected input. Therefore, a person skilled in the art will appreciate that various deviations from the described embodiments of the invention are 3o possible and that many modifications and improvements may be made within the scope and Doc. No. P 023 CA Patent spirit thereof. For example, the polarization rotator may be a half wave plate or two quarter-wave plates in series. The electrooptic device may be the same electrooptic prism depicted in Figure 2 or a set of electrooptic prisms optically connected. The components optically connecting the switch with the optic fiber may be a collimator as shown in Figures 7-11, and a s walk-off crystal as shown in Figures 12 and 13, and a lenslet array as shown in Figure 14, or any other equivalent device. The radiation paralleling device may be a collimator or any optical system that can increase the diameter of parallel beam. The electrooptic device may take the shape of a prism, a plate, an array of prisms, a series of prisms or plates, or other similar form.io Whereas many alterations and modifications of the present invention will no doubt become apparent to a person of ordinary skill in the art after having read the foregoing description, it is to be understood that any particular embodiment shown and described by way of illustration is in no way intended to be considered limiting. Therefore, references to details of various embodiments are not intended to limit the scope of the claims which in themselves Is recite only those features regarded as essential to the invention.
    权利要求:
    Claims (21)
    [1] 1. A method of steering a light beam comprising:a) receiving a light beam, the light beam propagating through a series of optical elements, at least one element of the series of optical elements having different indices of refraction for the transverse electric polarization and the transverse magnetic polarization; and b) deflecting the light beam into a specified location by the series of optical elements whose synchronized operation in determining the amount of deflection is insensitive to the light beam's polarization.
    [2] 2. The method of claim 1, wherein the deflecting of the light beam occurs by propagating a light signal through a polarization rotator located between two electrooptic devices.
    [3] 3 The method of claim 1, wherein the deflecting of the light beam comprises:a) decomposing the light beam into a first portion and a second portion having orthogonal polarizations with respect to each other, the first portion having a first state of polarization;b) rotating the polarization of the first portion to match the polarization of the second portion;c) routing the first portion and second portion through at least one electrooptic device;d) deflecting the angle of the light beam propagating through the electrooptic device by an amount proportional to a voltage applied to the electrooptic device;e) rotating the polarization of the first portion to the first state of polarization; and f) recombining the first and second portions into a single light beam.
    [4] 4. A method of steering optical beams comprising:a) receiving an input light beam; and b) steering the light beam by electrooptic deflection into desired location regardless of the polarization; and c) outputting the light beam at the desired location.
    [5] 5. A optical switch comprising:a) an input receiving a light beam;b) a plurality of outputs; and c) a means for steering a light beam into desired location regardless of the polarization the light beam, the steering means directing the light beam to one or more optical devices redirecting the light beam to appropriate outputs.
    [6] 6. A light beam steering apparatus comprising:a) a first electrooptic device having a body with a light transmissive portion, the first electrooptic device having one or more electrodes attached to the body;b) a second electrooptic device having a body with a light transmissive portion, the second electrooptic device having one or more electrodes attached to the body; and c) a polarization rotator optically coupled on one end to the first electrooptic device, the polarization rotator optically coupled on the other end to the second electrooptic device, the polarization rotator located between the first electrooptic device and the second electrooptic device.
    [7] 7. The beam steering apparatus of claim 6, wherein the polarization rotator is located substantially symmetrically between the first electrooptic device and the second electrooptic device.
    [8] 8. A light beam steering apparatus comprising:a) a first beam spatial-orientation device for dividing a beam of light into a first and a second subbeams having orthogonal polarisations;b) a first polarization rotator coupled to the first beam spatial-orientation device for rotating a polarisation of the first subbeam to match the polarisation of the second subbeam;c) a first optically-transparent device coupled to the first beam spatial-orientation device; d) a first electrooptic device coupled to a second optically-transparent device on one end and coupled to the first polarization rotator on the other end, the first electrooptic device having a body with a light transmissive portion, the first electrooptic device having an electrode attached to the body for applying a voltage to deflect the first subbeam;e) a second electrooptic device coupled to the first optically-transparent device on one end and coupled to a second polarization rotator on the other end for rotating the polarisation of the second subbeam to be orthogonal to the polarisation of the first subbeam, the second electrooptic device having a body with a light transmissive portion, the second electrooptic device having an electrode attached to the body for applying a voltage to deflect the second subbeam; and f) a second beam spatial-orientation device coupled on one end to the second optically-transparent device as well as the second polarization rotator for combining the deflected first and second beams into a selected output location.
    [9] 9. A polarization-insensitive beam-steering device comprising:a) an input;b) an electrically-controllable beam-steering device possessing at least one electrooptic component, the beam-steering device coupled to the input; and c) one or more beam-routing devices communicatively coupled to the beam-steering device on one end and coupled to an output on the other end.
    [10] 10. The polarization-insensitive beam-steering device of claim 9, wherein the beam-steering device comprises:a) an optical component coupled on one end to the input;b) a first electrooptic device coupled the other end of the optical component, the first electrooptic device having a body with a light transmissive portion, the first electrooptic device having one or more electrodes attached to the body;c) a second electrooptic device having a body with a light transmissive portion, the second electrooptic device having one or more electrodes attached to the body; and d) a polarization rotator coupled on one end to the first electrooptic device, the polarization rotator coupled on the other end to the second electrooptic device, the polarization rotator located between the first electrooptic device and the second electrooptic device.
    [11] 11. The optical switch of claim 9 wherein the one or more beam-routing devices comprises:a) a first electrooptic device communicatively connected to the beam-steering device on one end, the first electrooptic device having a body with a light transmissive portion, the first electrooptic device having one or more electrodes attached to the body;b) a second electrooptic device having a body with a light transmissive portion, the second electrooptic device having one or more electrodes attached to the body;c) a polarization rotator coupled on one end to the first electrooptic device, the polarization rotator coupled on the other end to the second electrooptic device, the polarization rotator located between the first electrooptic device and the second electrooptic device; and d) a walkoff crystal coupled to the second electrooptic device on one end and coupled to the output on the other end.
    [12] 12. The polarization-insensitive beam-steering device of claim 9, wherein the one or more beam-routing devices comprises:a) a segmented mirror communicatively connected to the beam-steering device;b) a plurality of adjustable prisms communicatively coupled to a portion on the segmented mirror;c) each of the adjustable prisms coupled on one end to a walkoff crystal; and d) each of the beam-routing devices coupled to an additional output.
    [13] 13. The polarization-insensitive beam-steering device of claim 9, wherein the one or more beam-routing devices comprises: a) a radiation-paralleling device on one end communicatively coupled to the beam-steering device, the radiation-paralleling device coupled to the output on the other end;b) a portion of a segmented mirror communicatively coupled to the beam-steering device;c) a beam spatial-orientation device communicatively coupled to the portion on the segmented mirror; and d) a walkoff crystal device coupled on one end to the beam spatial-orientation device and coupled on the other end to an additional output.
    [14] 14. The polarization-insensitive beam-steering device of claim 9, wherein the one or more beam-routing devices comprises:a) a Fourier lens communicatively connected to the beam-steering device;b) a plane micro lens array communicatively coupled to the Fourier lens; and c) a beam spatial-orientation device coupled on one end to the plane micro lens and on the other end coupled the output.
    [15] 15. The polarization-insensitive beam-steering device of claim 9, wherein the one or more beam-routing devices comprises:a) a plane micro lens array communicatively coupled to the beam-steering device; and b) a beam spatial-orientation device communicatively coupled on one end to the plane micro lens array, the beam spatial-orientation device coupled on the other end to the output.
    [16] 16. The polarization-insensitive beam-steering device of claim 9, wherein the beam-steering device comprises:a) a first beam spatial-orientation device;b) a radiation-paralleling device coupled on one end to the input and coupled on the other end to the first beam spatial-orientation device;c) a first polarization rotator coupled to the first beam spatial-orientation device;
    [17] 17 d) a first optically-transparent device coupled to the first beam spatial-orientation device;e) a first electrooptic device coupled to a second optically-transparent device on one end and coupled to the first polarization rotator on the other end, the first electrooptic device having a body with a light transmissive portion, the first electrooptic device having an electrode on the body;f) a second electrooptic device coupled to the first optically-transparent device on one end and coupled to a second polarization rotator on the other end, the second electrooptic device having a body with a light transmissive portion, the second electrooptic device having an electrode on the body; and g) a second beam spatial-orientation device coupled on one end to the second optically-transparent device as well as the second polarization rotator. 17. The polarization-insensitive beam-steering device of claim 9, wherein the beam-steering device comprises:a) a first beam spatial-orientation device;b) a radiation-paralleling device coupled on one end to the input, the radiation-paralleling device coupled on the other end to the first beam spatial-orientation device;c) a first polarization rotator coupled to the first beam spatial-orientation device;d) a first optically-transparent device coupled to the first beam spatial-orientation device;e) an electrooptic device coupled to the first optically-transparent device as well as a first polarization rotator on one end, the electrooptic device coupled to a second polarization rotator as well as a second optically-transparent device on the other end, the electrooptic device having a first electrooptic plate and a second electrooptic plate disposed in one plane of the electrooptic device; and f) a second beam spatial-orientation device coupled on one to the second optically-transparent device as well as the second polarization rotator.
    [18] 18. The polarization-insensitive beam-steering device of claim 9, wherein the one or more beam-routing devices further comprises a beam-divergence compensation device communicatively coupled on one end to the beam-steering device, the beam-steering device communicatively coupled on the other end to the one or more wavelength-routing devices.
    [19] 19. The polarization-insensitive beam-steering device of claim 9, wherein the beam-steering device comprises:a) a first lenslet array coupled to the input;b) a first electrooptic device coupled to the lenslet array, the first electrooptic device having a body with a light transmissive portion, the first electrooptic device having one or more electrodes disposed approximate to the body;c) a second electrooptic device having a body with a light transmissive portion, the second electrooptic device having one or more electrodes disposed approximate to the body;d) a polarization rotator coupled on one end to the first electrooptic device, the polarization rotator coupled on the other end to the second electrooptic device, the polarization rotator located between the first electrooptic device and the second electrooptic device;e) a Fourier lens communicatively connected on one end to the second electrooptic device;f) a third electrooptic device communicatively coupled to the Fourier lens, the third electrooptic device having a body with a light transmissive portion, the third electrooptic device having an electrode means disposed approximate to the body;g) a second polarization rotator coupled on one end to the third electrooptic device and on the other end to a fourth electrooptic device, the second polarization rotator located between the third electrooptic device and the fourth electrooptic device;h) the fourth electrooptic device having a body with a light transmissive portion, the fourth electrooptic device having an electrode disposed approximate to the body; and i) a second lenslet array coupled to the fourth electrooptic device on one end and coupled to the output on the other end.
    [20] 20. The polarization-insensitive beam-steering device of claim 9, wherein the beam-steering device comprises:a) a radiation-paralleling device coupled on one end to the input;b) a first electrooptic device coupled to the radiation-paralleling device, the first electrooptic device having a body with a light transmissive portion, the first electrooptic device having one or more electrodes attached to the body;c) a second electrooptic device having a body with a light transmissive portion, the second electrooptic device having one or more electrodes attached to the body; and d) a polarization rotator coupled on one end to the first electrooptic device, the polarization rotator coupled on the other end to the second electrooptic device, the polarization rotator located between the first electrooptic device and the second electrooptic device.
    [21] 21. A telecommunication fiber optics system for routing light beams to communicate information comprising:a) a light beam transmitter, the transmitter generating a plurality of light beams having different wavelengths;b) a light beam modulator, the modulator imparting information to be carried by the light beam;c) a transmission channel;d) a receiver having an optical detector and decoding device for retrieving the information carried by the light beam; and e) at least one optical switch, the operation of the optical switch being independent of the polarization of a light beam, the optical switch having an electronically-controllable means to deflect the light beam.
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    同族专利:
    公开号 | 公开日
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    2003-10-27| FZDE| Dead|
    优先权:
    申请号 | 申请日 | 专利标题
    US43051999A| true| 1999-10-29|1999-10-29||
    US09/430,519||1999-10-29||
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