MXPA01008950A - Piezoelectric optical switch device - Google Patents

Abstract

A piezoelectric optical switch (10) includes a planar Mach-Zehnder optical device having a piezoelectric rib (40) disposed on one or both of the waveguide structures (20, 30). The piezoelectric rib (40) deforms the waveguide structure creating a strain vector that alters the optical path of the waveguide (20). The piezoelectric rib (40) is offset from the propagation path in the waveguide (20). By positioning the piezoelectric rib (40) away from the waveguide, the strain components in the propagation path of the waveguide in the directions perpendicular to the direction of propagation, e.g., in the x-direction and the y-direction, are negligible. Since strains in these directions create birefringence, elimination of these strains will minimize the birefringence. The piezoelectric switch of the present invention provides a high extinction ratio and a low power consumption and small switching time expected of piezoelectric devices.

Description

PIEZO ELECTRIC OPTICAL SWITCHING DEVICE BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates generally to piezoelectric optical switches and particularly to Mach-Zehnder piezoelectric flat optical switches having low birefringence and high extinction ratio.

PREVIOUS TECHNIQUE As demand for bandwidth increases, so does the drive to smart fiber networks, low cost and dynamically reconfigurable. To achieve this, network designers are looking for ways to replace certain network functions that were traditionally performed in the electrical domain with solutions in the optical domain, as economics and system designs allow. Designers have recognized for some considerable time that four-door optical devices could find wide application in fiber networks to provide fault tolerance, signal modulation and signal routing. Devices are commonly available Intregrated optics that use thermo-optical or electro-optical techniques. However, these devices have drawbacks due to high power consumption and low switching speeds. Piezoelectric four-door optical devices are of particular interest because of their low power consumption, reduced switching time and adaptability to mass production techniques, such as photolithography. One approach that has been considered involves an optical phase modulator that is manufactured by coating a fiber with a thick coaxial piezoelectric film of lead zirconate-titanate. This circular symmetric circular fiber phase modulator provides phase modulation in a frequency range of 100 kHz to 25 MHz. Unfortunately, the efficiency of the device was poor, since it exhibited high attenuation and low piezoelectricity, due to the difficulty of deposit a thick PZT film around an optical fiber. In another approach that has been considered, a device was used Mach-Zehnder made of optical fibers to build an optical switch. In this design, each fiber optic branch was placed directly on a piezoelectric strip. This design also has several drawbacks. First, the piezoelectric strip required high voltage for commutation. Secondly, the placement of the strip in relation to the fiber creates asymmetric stresses along the axis of the fiber that disturbed the polarization in the interferometer branches resulting in high birefringence and degraded diaphthal performance. As a consequence, polarized light is required when this switch is used. In still another approach, a modulator was fabricated by laminating a piezoelectric strip on a flat waveguide device. A piezoelectric strip was formed by sandwiching a layer of piezoelectric material between a lower electrode and an upper electrode. The piezoelectric strip was then attached to the coating of the device directly above the waveguide. However, when the piezoelectric strip was operated, the resulting stress vector generated a strong birefringence effect that severely degraded the extinction rate at the output of the device. Thus, there is a need for a piezoelectric four-door optical device having reduced birefringence characteristics, high extinction rate, lower energy consumption and reduced switching time. This switch must be cost effective and its design suitable for mass production techniques.

BRIEF DESCRIPTION OF THE INVENTION The present invention is a piezoelectric four-port optical switch that substantially solves the problem of birefringence and addresses the other issues discussed above. In doing so, the piezoelectric switch of the present invention provides a high extinction rate in addition to the lower power consumption and reduced time of Possible switching with piezoelectric switch technology. The flat design of the present invention is well suited for mass production techniques, such as photolithography, and offers a promising low-cost solution for some of the functionality of signal addressing and fault tolerance that is needed to carry to practice an intelligent fiber optic network. One aspect of the present invention is an optical device for selectively addressing a light signal in a propagation direction, wherein the optical device includes a propagation path for the light signal and an output. The optical device includes a piezoelectric element for directing the light signal to the output, creating a plurality of mutually orthogonal stress components in the optical device, in which the piezoelectric element is disposed in relation to the propagation path in such a way that it can there is substantially in the propagation path only one component of the plurality of mutually orthogonal stress components, aligned in the propagation direction. In another aspect, the present invention is an optical Mach-Zehnder device for addressing a light signal having a wavelength? in a propagation direction. The optical device includes: a first waveguide having a first propagation path, a refractive index n, a first length Li and a first output, in which the light signal propagates along the first propagation path; and a first highlight piezoelectric to direct the light signal, creating a first plurality of mutually orthogonal stress components in the first waveguide, in which the first piezoelectric projection is disposed on the first waveguide in a first deviation of the first propagation path of such that it can exist substantially in the first propagation path only in one component of the first plurality of mutually orthogonal stress components, which is aligned in the propagation direction. In another aspect, the present invention is a method for directing a light signal having a wavelength?, In a propagation direction in an optical device including a first waveguide having a first propagation path, an index of refraction n, a first length Li and a first output, in which the light signal propagates along the first path of propagation. The method for directing a light signal includes the steps of: providing a first piezoelectric shoulder to generate a first plurality of mutually orthogonal stress components in the first waveguide, in which the first piezoelectric shoulder is disposed over the first waveguide in a first deviation of the first propagation path such that there can substantially exist in the first propagation path only one component of the first plurality of mutually orthogonal stress components, which is aligned in the propagation direction; provide a second waveguide arranged adjacent to the first waveguide having a second path of propagation, the refractive index n, a second length L2 and a second output; and actuating the first piezoelectric shoulder to selectively form the first waveguide, wherein a first deformation of the waveguide produces the first plurality of mutually orthogonal stress components in the first waveguide. In another aspect, the present invention sets forth a method of manufacturing an optical device used to address a light signal. The manufacturing method includes the steps of: forming a substrate; depositing a waveguide core layer on the substrate; forming a first waveguide from the waveguide core layer, wherein the first waveguide structure is characterized by a first propagation path, a refractive index n, a first length L ?, and a first axis, wherein the first axis is substantially perpendicular to the first length and the first propagation path; forming a second waveguide structure from the waveguide core layer, wherein the second waveguide structure is characterized by a second propagation path, the refractive index n, a second length Li and a second axis parallel to the first axis; arranging a first piezoelectric shoulder on the first waveguide structure, wherein the first piezoelectric shoulder has a first shoulder axis that is substantially parallel to the first axis and spaced apart from the first axis; and disposing a second piezoelectric shoulder on the second waveguide structure, wherein the second piezoelectric shoulder has a second shoulder axis that is substantially parallel to the second axis and separated from the second axis by the offset, in which the offset is selected to minimize birefringence in the optical device. In another aspect, the present invention sets forth a method for selectively addressing a light signal to a first output and a second output of an optical device that includes at least one waveguide having at least one core connected to the first output. , wherein the first signal propagates at least along a waveguide in a propagation direction, the method comprising selectively addressing a light signal the steps of: providing at least one piezoelectric element for switching the signal of light from the first output to the second output, inducing a plurality of mutually orthogonal stress components in at least one waveguide, the piezoelectric element (at least one) being disposed on the waveguide (at least one ) in a predetermined position such that there exists substantially in the core (at least one) only a first component of the plurality of components mutually orthogonal stresses, in which the first component is a stress component aligned with the direction of propagation; and actuating the piezoelectric element (at least one) to thereby generate an effort and the waveguide (at least one) causing the plurality of mutually orthogonal stress components to occur in the waveguide (at least one ).

The features and advantages of the invention will be disclosed in the detailed description that follows and in part will be readily apparent to those skilled in the art from the description and will recognize it by practicing the invention as described herein, including the detailed description that follows, the claims, as well as the accompanying drawings. It is to be understood that both the foregoing general description and the following detailed description are merely exemplary of the invention and are intended to provide a general overview or structure for understanding the nature and character as claimed. The attached drawings are included to provide a greater understanding of the invention, and are incorporated in this specification and constitute part of it. The drawings illustrate various embodiments of the invention and together with the description serve to explain the principles and operation of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic of a piezoelectric optical switch according to the first embodiment of the present invention; Figure 2 is a detailed view of the placement of a piezoelectric ledge on a waveguide structure according to the present invention; Figure 3 is a schematic of a piezoelectric optical switch according to a second embodiment of the present invention; Figure 4 is a table showing the relationship between the birefringence and the extinction ratio of the present invention; Figure 5 is a schematic of a piezoelectric optical switch according to an alternative embodiment of the present invention; Figure 6 is a detailed view of an acid-etched groove that is used to mechanically isolate the branches of a Mach-Zehnder device to reduce diaphtia; Figure 7 is a schematic of a piezoelectric optical switch according to another alternative embodiment of the present invention; Figure 8 is a schematic of a piezoelectric optical switch according to another alternative embodiment of the present invention; Figure 9 is a diagram of a piezoelectric optical device characterized by a variable attenuation controller according to another alternative embodiment still of the present invention; Figure 10 is a diagram of a piezoelectric optical device characterized by an optical modulator according to another alternative embodiment still of the present invention; Figures 11A-Q are sequential schematic views of the piezoelectric optical switch of the present invention in successive stages of manufacture.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numbers will be used throughout the drawings to refer to the same or similar parts. An exemplary embodiment of the piezoelectric optical switch of the present invention is shown in FIG. 1 and is designated generally throughout the present case with the reference number 10. In accordance with the present invention, an optical device 10 for addressing a signal of Light to a desired output includes a piezoelectric ledge 40. The piezoelectric ledge 40 directs the light signal by deforming the core of at least one waveguide to thereby alter the length of the optical path. The deformation creates a three-dimensional stress vector and has components in each dimension x, y and z, of a Cartesian coordinate system. The z address corresponds to the propagation direction. By placing the piezoelectric shoulder 40 on a waveguide in a predetermined offset position from the core, the stress components that are orthogonal to the direction of propagation, x and y. Since efforts in these directions create birefringence, a reduction of these efforts will also effect a reduction of birefringence, in addition. The only remaining reformation is in the direction of propagation and the effort in the z direction does not create birefringence. The elimination or reduction of birefringence is considerably required because the birefringence degrades the extinction rate at the outlet of the optical expose 10. Thus, by solving the question of birefringence, the present invention provides an optical switch having a high extinction rate. . Another benefit of the present invention is its low power consumption and short switching time, due to the piezoelectric effect. In addition, the flat design of the present invention is well suited for mass production techniques, such as photolithography, and thus offers a promising low-cost solution for some of the functionality of signal addressing and fault tolerance that is They need to implement an intelligent fiber optic network. As is modalized herein and shown in Figure 1, a schematic of a piezoelectric optical switch 10 according to a first embodiment of the present invention includes a flat directional coupler 100 formed by the waveguide 20 and the waveguide. 30. The piezoelectric ledge 40 is disposed on a waveguide structure 20 at a predetermined deflected distance "d" from the waveguide core 22 (see in Fig. 2). The piezoelectric shoulder 40 has a length Lp, one sufficiently long distance necessary to produce a phase difference of p radians between the waveguide 20 and the waveguide 30. As is modalized herein and shown in Figure 2, a detailed view of the placement of a piezoelectric shoulder 40 on a waveguide structure 20 according to the present invention. A rectangular coordinate system is provided in Figure 2 as a convenient means for describing the orientation of the elements and will be used throughout the present. The piezoelectric shoulder 40 includes an upper electrode 42 and a lower electrode 44. The electrodes 42 and 44 are connected to the actuator 50. The piezoelectric shoulder 40 is disposed on the coating 24 of the waveguide structure 20 at a deviated distance "d "of the waveguide axis bisecting the waveguide core 22. The waveguide structure 20 includes the sheath 24 and the core 22. Note that the direction of propagation is in the z-direction. The waveguide structure 20 and the waveguide structure 30 can be of any suitable well-known type, but there is shown by way of example a waveguide which is manufactured using silica glasses with a refractive index of about 1.45. One skilled in the art will appreciate that polymers and other similar materials can be used. The geometrical shape of the core 22 can be either square, rectangular, trapezoidal or semicircular. The dimensions of the core are dependent on the wavelength of the signal light and are designed to ensure that the waveguide is in single mode in the wavelength of the signal. The core 22 is covered by the coating 24 having a thickness which is designed to restrict the mode and limit the propagation appearances. The piezoelectric shoulder 40 can be of any suitable well-known type, but a zirconate-lead titanate (PZT) or zinc oxide (ZnO) layer having a thickness in a range of approximately 3 μm is shown by way of example. at 300 μm, a width in an approximate range of between 20 μm and 300 μm, and a length in a range of approximately 2 mm to 3 cm. The variation of the dimensions of the piezoelectric shoulder is dependent on several factors, including the amount of phase change that is required to produce the piezoelectric shoulder 40. Piezoelectric shoulder 40 is produced by spin coating deposition of a sol-gel solution of PZT or ZnO and by annealing. A more detailed discussion of the inventions and placement of the piezoelectric shoulder 40 will subsequently be presented. The actuator 50 can be of any suitable well-known type, but illustrated by way of example is a voltage source capable of supplying two discontinuous voltages to the piezoelectric shoulder. 40. The first discontinuous voltage is in the order of a few volts. The exact voltage depends on the required phase change. The second voltage level is approximately grounding. As one skilled in the art will appreciate, Mach-Zehnder devices with perfect 3 dB couplers do not exist in practice. Being so, the actual voltage that the actuator 50 The supply to the piezoelectric header 40 can include a bias voltage to compensate for the small phase variations generated by the imperfections in the Mach-Zehnder device. This "resonance adjustment" can be made permanently by exposure to UV radiation from the waveguide to refine the required phase difference. The network interface 60 allows the optical device 10 to be adaptable to any network environment in terms of line levels and logical protocol. The network interface 60 may also be configured to send defective information back to the network. The operation of the optical device 10 according to the first embodiment of the present invention, as shown in figures 1 and 2, is as follows. In a first actuation state, the network interface receives a control signal for directing a light signal to the output of the waveguide 30. The network interface 60 drives the actuator 50 and the piezoelectric projection 40 is turned off. directs the light signal to the directional coupler 100 as shown and transfers the signal energy to the waveguide 30. In a second state, the network interface receives a command signal which directs the optical device 10 to address all the light signal at the output of the waveguide 20. In response, the network interface 60 drives the actuator 50 to supply the piezoelectric shoulder 40 with the appropriate voltage. The piezoelectric shoulder 40 expands and deforms the waveguide structure 20 to induce an effort in the waveguide 20. The induced stress caused by the deformation will cause the refractive index and the length of the waveguide 20. These two factors contribute to a change in the length of the optical path in the waveguide 20. A phase difference of p radians is established between the waveguide 20 and the waveguide 30 and the light is no longer coupled to the waveguide 30. As a result, it is switched to the optical device 10 and the light signal leaves the device 10 of the waveguide 20 as discussed above, an expert In the art it will be appreciated that the amount of voltage depends on the amount of effort required to produce an index variation that generates the phase difference that is desired. The operating principles of the present invention which establish the relationship between the dimensions, the energy requirements and the location of the piezoelectric ledge 40 with respect to the deformation, stress and resultant phase change induced in the waveguides 20 and 30 are as follows. If Eentrada is the field of the input light signal,? F is the phase difference between the waveguides 20 and 30, and Esa? ¡Da is the field of the output signal, we have the following relationship: ^ -M. = ^ a? * - a + ß 4F) (? The transmission of the Mach-Zehnder 100 device is defined as the ratio of the output current to the input current. Thus, by equation (I) we have: r = Warm = 1 + CQS (? F) (2) entry It is expressed unlike phase? F between waveguide 20 and 30 with: TO ? 2pd (nL) 2pL, dL? F = - - = (n - + d?) (3)? ? L in which ? is the wavelength, n is the effective rate of the mode propagating in the device 10 and L is the length of the waveguides 20 and 30 between the coupler 112 and the coupler 114. The term d (nL) is the nL difference between the waveguides 20 and the waveguide 30. As discussed above, when the actuator 50 applies a voltage to the piezoelectric ledge 40, it expands or contracts, depending on the magnitude and voltage polarity. The expansion and contraction of the piezoelectric shoulder 40 deforms the waveguide 20 and causes a change in the refractive index and length. The variation of the index is related to the effort by means of the following expression: H3 dn? = - U > uex + pney + pue,) (4) where nx is the refractive index of the polarized light of the x direction (see Figure 3), n and is the refractive index of the polarized light and the 5 direction and, ex, ey, and ez = dL / L are mutually orthogonal stress components in the directions x, y and z, respectively. The terms pn and P? 2 are photoelastic coefficients and vary depending on the material used to manufacture the waveguide. The phase difference? F between the waveguide 20 and the 30 is generally different for the polarization components of the light signal in the x direction and in the direction y, therefore: -. c? ? 2? ZL. n3 n3 rn3. . 2pL ^ ._.

From equations (6) and (7), it is possible to calculate piezoelectric shoulder length 40 which is required to produce a phase difference of p radians: 0 ? Lp = - (8) K, + K " Depending on the material used and the wavelength of the light signal, Lp has an approximate interval of 2 mm and 3 cm. The acceptable range of widths and thicknesses of the piezoelectric shoulder 40 is determined by comparing the stress in the propagation direction ez, the PZT shoulders having various widths and thicknesses, and the waveguide structures having different coating thicknesses. Thus, for acceptable results, the thickness of the piezoelectric shoulder 40 has an approximate range of 3 μm -300 μm 'and its width has a range of approximately 20 μm - 300 μm. The depth of the coating depends on the wavelength of the signal and must be sufficient to restrict the mode and limit the propagation measures. From equations (6) and (7), it is also evident that the phase difference depends on the polarization, due to the birefringence. The main effect of birefringence is to decrease the extinction rate. The extinction ratio refers to the proportion of light at the output of the waveguide 20, for example, in the "connected" state with respect to the "disconnected" state. Theoretically, there should be no light coming out of waveguide 20 in the "disconnected" state. Thus, the extinction ratio is a measure of light leakage. Obviously, the output of the waveguide 30 could also be used to make the measurement. If the proportion of Extinction is low, means that there is an excessive amount of light that is leaking from the device 10 of the output of a waveguide that is supposed to be disconnected. By decreasing the birefringence of the device, the extinction rate is also improved. Figure 3 is a table showing the relationship between birefringence and the extinction rate. One measure of birefringence is the Q value. The upper curve shows a non-birefringent Mach-Zehnder device that corresponds to an infinite Q value. The lower curve shows a device that has an extinction ratio of 10 dB that corresponds to a Q value of approximately 5. The Q value must be greater than 16 to obtain a minimum extinction ratio of 20 dB. The Q value is related to the difference of refractive indices for both polarizations by means of the expression: dn + dn. Q = (9) dnr -dn.

The parameters dnx and dny are index variations produced by the stresses induced by the piezoelectric ledge 40. Equations (6) and (7) indicate that the change in the waveguide length dL / L and the index ratio induced by deformation compensates for the stress in the direction of propagation ez. This being the case, birefringence can be minimized significantly, eliminating ex-effort components and and in the directions x and y, respectively. This is accomplished by the present invention, exposing the piezoelectric shoulder 40 at a predetermined offset distance from the central axis of the core 22 (see FIG. 3) and the propagation path. At the moment of actuation, the geometric position of the piezoelectric shoulder acts to minimize the stress components ex and ey; however, the switching functionality is retained, using ez to vary the index and length of the waveguide. The optimal range for the deviated distance was determined, representing the Q value (inversely proportional to the birefringence) as a function of the deviated distance using a Mach-Zehnder device having a PZT shoulder having a length Lp, a width of approximately 100 μm and a thickness of 20 μm. Under these conditions, the optimum value of the distance deviated in this configuration is approximately 100 μm. Generally speaking, the deviated distance is approximately equal to? / 4n. As is modalized herein and shown in Figure 4, a piezoelectric optical switch 10 according to a second embodiment of the present invention includes a Mach-Zehnder device 100 formed by the waveguide 20 and the waveguide. A piezoelectric shoulder 40 is disposed on the waveguide structure 20 at a deflected distance "d" from the waveguide core 22 (see Figure 2). The piezoelectric shoulder 40 has a length equal to Lp. The piezoelectric shoulder 40 is electrically connected to the actuator 50. The actuator 50 is connected to the network interface 60, which receives control signals from the network and drives the actuator 50 in compliance. The operation of the optical device 10 according to the second embodiment of the present invention, as shown in FIG. 4, is as follows. In a first actuation state, the network interface receives a control signal for directing the light signal at the output of the waveguide 30. The network interface 60 drives the actuator 50 and the piezoelectric projection 40 is de-energized. A light signal is routed to the Mach-Zehnder 100 device as shown. Half of the light signal is coupled to a waveguide 30 via the 3 dB coupler 112. As will be appreciated by a person skilled in the art, a symmetrical March-Zehnder device with perfect 3 dB couplers operates in the diaphoty state when no phase difference between the waveguides 20 and 30 occurs and the light signal will leave the device 10 of the output of the waveguide 30. In a second state, the network interface receives a command signal which directs the light signal to exit the optical device 10 from the output of the waveguide 20. In response, a network interface 60 drives the actuator 50 to supply the piezoelectric shoulder 40 with the voltage necessary to induce a phase difference of p radians. The piezoelectric shoulder 40 expands and deforms the waveguide structure 20 by inducing a stress in the waveguide 20. The induced stress caused by the deformation will cause the refractive index and the length of the waveguide to change 20. These two factors contribute to a change in length of the optical path that follows the light signal when propagated in the waveguide 20. One skilled in the art will appreciate that the amount of voltage that is required depends on the amount of effort required to produce an index variation that generates the phase difference that is desired. The phase difference determines the magnitude of the electric field that is required to drive the piezoelectric element 40. The supply voltage to the piezoelectric header 40 establishes a p-radian stack phase difference between the waveguide 20 and the waveguide 30. As a result, the optical device 10 is combined and the light signal leaves the device 10 of the waveguide 20. In a third embodiment of the invention, as is modeled herein and as shown in figure 5, a scheme of the device Mach-Zehnder optical piezoelectric 10 includes a Mach-Zehnder 100 flat device formed by the waveguide 20 and the waveguide 30. A piezoelectric boss 40 is disposed on the waveguide structure 20 by offsetting a distance "d" of the waveguide 20. Another piezoelectric projection 70 is disposed on the waveguide structure 30 also deflected a distance "d". The piezoelectric projections 40 and 70 could also be arranged on the inner sides of the waveguides 20 and 30, respectively. Note that figure 2 and the discussion of the deviated distance "d" applies to this modality as well as the first modality. The piezoelectric shoulder 40 is electrically connected to the actuator 50 and the The piezoelectric ledge 70 is electrically connected to the actuator 52. The actuators 50 and 52 are driven in tandem by the network interface 60. It will be apparent to those skilled in the pertinent art that modifications and variations can be made to the piezoelectric projections 40 and 70 depending on the amount of base change that is required to provide each highlight. In the second embodiment of the present invention, the switching functionality is distributed between the waveguides 20 and 30, by placing a second piezoelectric shoulder 70 on the waveguides 30. As in the first embodiment, a phase difference must be provided total of p radians between the waveguide 20 and the waveguide 30 to connect the light signal to the wave output 20. However, the use of the piezoelectric hump 70 makes it possible to use a "push-pull" effect "in which the piezoelectric bulge 40 provides a positive phase change and piezoelectric bulge 70 provides a negative phase change. Thus, the piezoelectric shoulder 40 must provide a phase change of plus + p / 2 radians and the piezoelectric shoulder 70 must provide a phase change of -p / 2 radians. Since the phase change required to provide each piezoelectric shoulder of p radians to p / 2 radians has been reduced, the length of each shoulder can also be reduced by approximately a factor of two: in what so? .5. To avoid problems associated with mechanical diaphysis, the piezoelectric projections 40 and 70 should be separated with a minimum distance of 500 μm. The recommended separation interval is between 500 μm and 1000 μm. This is an intermediate solution between the size of the device and the diaphhoty. As is modalized herein and depicted in Figure 6, an alternative embodiment of the present invention may include an acid-etched slot 80 between the waveguide 20 and the waveguide 30. The etched 80 acid slot is provided. to reduce mechanical diaphysis, by isolating the branches 20 and 30 of the Mach-Zehnder 100 device. The operating principles of the present mention establishing width, thickness, energy requirements and placement and piezoelectric ledges 40 and 70 with with respect to the stress and phase change induced in the waveguides 20 and 30 are essentially identical to those discussed above with respect to the first embodiment shown in FIGS. 1 and 2. The operation of the optical device 10 according to the third embodiment of the present invention, as depicted in Figure 5, is as follows. In a first actuation state, the needs of the network require that the light signal is routed to the output of the waveguide 30. Half of the light signal entering the Mach-Zehnder device 100 is coupled to the waveguide 30 with the coupler 112 of 3 dB. A symmetrical Mach-Zehnder device with perfect couplers 112 and 114 of 3 dB will operate in the diaphoty state when no phase difference between the waveguides 20 and 30 will be output and the light signal will exit the waveguide output 30. Thus, when processing the control signal of the network, the network interface 60 drives the actuators 50 and 52 and the voltage supplied to the piezoelectric projections 40 and 70 from 7 to approximately zero volts. As discussed above and as one skilled in the art will appreciate, Mach-Zehnder devices with perfect 3 dB couplers do not exist in practice. In each switching state, the actuators 50 and 52 supply the piezoelectric poles 40 and 70, respectively, with the smallest nominal voltages of polarization voltages to compensate for the small phase variations generated by the imperfections of the Mach-Zehnder device. In a second actuation state, control signals are sent to the network interface to address the light signal at the output of the waveguide 20. The network interface 60 drives the actuators 50 and 52 in accordance. The actuator 50 supplies a positive voltage to the piezoelectric ledge 40 and the actuator 52 supplies a negative voltage of approximately the same magnitude to the piezoelectric ledge 70. The piezoelectric ledge 40 will expand when it deforms the waveguide structure 20. The piezoelectric ledge 70 is it will contract when it deforms the waveguide structure 30. The deformations subject the waveguides 20 and 30 to stress and thereby change their track lengths. The variation of the guide length in the waveguide 20 results in a phase change of approximately + p / 2 radians while the variation of the guide length in the waveguide 30 produces a phase change of approximately -p / 2 radians. This being the case, a phase difference of p radians, or a non multiple of p radians, is established between the waveguide 20 and the waveguide 30 and the light signal is routed to the output of the waveguides 20. Of course, the polarities of the voltages can be inverted to produce the same results. However, voltages must have opposite polarities. In another alternative embodiment of the present invention as is modalized herein and as shown in Figure 7, a piezoelectric ledge 40 consists of an outer piezoelectric strip 46 disposed on an outer side of the waveguide 20 and a piezoelectric strip. interior 48 disposed on an inner side of the waveguide 20. The piezoelectric ledge 70 consists of an outer piezoelectric strip 72 disposed on an outer side of the waveguide 30 and an inner piezoelectric strip 74 disposed on the inner side of the guide of waves 30. The inner piezoelectric strip 48 and the internal piezoelectric strip 74 are separated by a minimum of 500 μm, the distance being within the recommended separation interval between 500 μm and 1000 μm, as discussed above and shown in the figure 7. This is an intermediate solution between the diaphhoty and the size of the device. The slot engraved with acid shown in Figure 6 could also be used in this embodiment. The actuator 50 is connected to the piezoelectric parts 46 and 48, supplying them with identical voltages. The actuator 52 is connected to the piezoelectric strips 72 and 74, supplying them with identical voltages. The network interface 60 is connected to the actuator 50 and the actuator 52, and drives them in tandem. It will be apparent to those skilled in the pertinent art that modifications and variations can be made to the high piezoelectric 40 and 70 of the present invention, the amount of phase wire that is required to be provided by each depending. By placing the piezoelectric strips 46, 48, 72 and 74 on both sides of their respective waveguides 20 and 30, the length of the piezoelectric highs can be reduced by a factor of two with respect to the second mode and a factor of four with respect to the second mode. to the first modality. Thus, in equation (10), a = 0.25. With the exception of the variations discussed above, the optical switch 10 in FIG. 7 operates in the same manner as the embodiment shown in FIG. 5 and therefore a description of its operation will not be repeated. In still another alternative embodiment, as is modalized herein and as shown in Figure 8, a scheme of the piezoelectric optical switch 10 includes a Mach-Zehnder device 100 formed by the waveguide 20 and the waveguide 30. The piezoelectric shoulder 40 is disposed on a waveguide structure 20 with a distance offset from the guide core 22. Another piezoelectric shoulder 70 is disposed on the waveguide structure 30, also disposed a distance offset from the core. The discussion of the distance deviated from the Figure 2 applies to this modality, in addition. The piezoelectric shoulder 40 is electrically connected to the actuator 50. The piezoelectric shoulder 70 is electrically connected to the actuator 52. The actuators 50 and 52 are connected to the network interface 60 driven in tandem by it. The actuator 50 and the actuator 52 may be of any suitable well-known type, but a voltage source capable of supplying three discontinuous voltages to the piezoelectric ledge 40 and the piezoelectric ledge 70 is shown by way of example. push-pull "similar to the technique discussed above with respect to a previous embodiment. The commutated commutation in piezoelectric bulge 40 and the piezoelectric bulge 70 are performed with voltages having opposite polarities. Being that way, the voltage sources operate in tandem such that the actuator 52 supplies -V volts when the actuator 50 supplies + V volts. When the actuator 50 supplies -V volts, the actuator 52 is supplying + V volts. When the actuator 50 is approximately in connection with ground, so is the actuator 52. As discussed above, the nominal voltage V is dependent on a variety of factors, such as the phase difference and desired size of the piezoelectric shoulder. . It will be apparent to one skilled in the relevant art that multiple voltage combinations can be used to separate the light signal between the waveguides 20 and 30, as desired. It will be apparent to those skilled in the pertinent art that modifications and variations may be made to the present invention, depending on the amount of phase change that is required to provide each highlight. In FIG. 8, the waveguide 20 is shorter than the waveguide 30 by a distance? L = L2-L ?, which is approximately 250 μm when ? = 1.55 μm and n = 1.5. This difference in the length of the day between the waveguide 20 and the waveguide 30 establishes a phase difference of p / 2 radians between the waveguide 20 and the waveguide 30. Thus, having obtained in order to obtaining the phase change of p radians or the phase change 0 between the waveguides 20 and 30, it is only required that each of the piezoelectric elements 40 and 70 produce a phase change of p / 4 radians. Since the phase change that must be provided by the piezoelectric shoulder 40 and the piezoelectric shoulder 70, of p radians to p / 4 radians, the length can also be reduced by approximately a factor of four. Thus, it is possible to use equation (10) to calculate the lengths L (p / 4), and piezoelectric projection 40 and piezoelectric projection 70, where a = 0.25. one skilled in the art will also recognize that this mode can be practiced using a piezoelectric ledge or four piezoelectric ledges. It will be apparent to those skilled in the relevant art that modifications and variations can be made to the present invention shown in Figure 8. Instead of designing the difference in length of the tracks to provide a phase difference of p / 2 radians, you can design the difference in length of the tracks to provide a permanent difference of phase of p radians. In this case, when the piezoelectric projections are not actuated, the optical device 10 is in the subdivision state rather than in the diaphhotic state. This design is of interest when it is more likely to be used in the switch in the subdivision state rather than in the cross state. As discussed above with respect to an earlier embodiment, to avoid problems associated with mechanical diaphysis, the piezoelectric projections 40 and 70 must be separated by a minimum distance of 500 μm. The recommended separation interval is between 500 μm and 1000 μm. As discussed above, the separation interval is an intermediate solution between the diaphhoty and the size of the device. The slot engraved with acid shown in Figure 6 can also be used in this embodiment. The operation of the optical device 10 according to the invention, as presented in Figure 8, is as follows. In a first actuation state, the network sends control signals to the optical device 10 to direct the light signal to the output of the waveguide 20. The network interface 60 drives the actuators 50 and 52 in compliance. The actuator 50 supplies a positive predetermined voltage to the piezoelectric ledge 40. The actuator 52 applies a negative voltage of the same magnitude to the piezoelectric ledge 70. The piezoelectric ledge 40 deforms the waveguide 20 and a phase change of about p / is generated. 4 radians. The piezoelectric shoulder 70 deforms the waveguide 30 and is generated a phase change of approximately -p / 4 radians. As one skilled in the art will recognize, the actual phase changes are dependent on the imperfections inherent in the MZ1. The phase variation may be slightly different in each. The requirement is that the total phase difference of p radians be established between the waveguide 20 and the waveguide 30. In doing so, the optical device 10 is switched and the light signal leaves the device of the guide output 20. In a second actuation state shown in FIG. 8, the actuators 50 and 52 supply approximately 0 volts to their respective piezoelectric projections 40 and 70. As discussed above, the asymmetric Mach-Zehnder device of the Figure 8 having an inherent phase difference of approximately p / 2 radians between the waveguide 20 and the waveguide 30. This being so, when piezoelectric projections 40 and 70 are not deforming the waveguide 20 and 30, respectively, the inherent phase difference of p / 2 radians causes the light signal to be equally divided between the outputs of the waveguides 20 and 30. In this state, the optical device 10 is a 3 dB splitter. In a third actuation state, control signals are sent to the network interface 60 to direct the light signal to the output of the waveguide 30. The network interface 60 drives the actuator 50 for when supplying the projection piezoelectric 40 with a negative voltage. Similarly, the actuator 52 supplies the piezoelectric ledge 70 with a positive voltage of approximately the same magnitude. The piezoelectric shoulder 40 deforms the waveguide 20 and generates approximately a phase change of -p / 4 radians. The piezoelectric shoulder 70 deforms the waveguide 30 and approximately a phase change of + p / 4 radians is generated. In this actuation state, the phase changes generated by the piezoelectric poles 40 and 70 cancel the inherent phase difference of p / 2 between the waveguide 20 and the waveguide 30 caused by their difference in track lengths. Thus, there is no phase difference between the waveguide 20 and the waveguide 30 and the light signal is routed to the output of the waveguide 30, as the control signals are sent. In still another alternative embodiment, as is modalized herein and as shown in Figure 9, a piezoelectric variable alternator scheme 10 includes a Mach-Zehnder device 100 formed by the waveguide 20 and the waveguide 30. The piezoelectric shoulder 40 is disposed on the waveguide structure 20 at a distance offset from the waveguide core 22. The discussion of the deviated distance with respect to FIG. 2 equally applies to this embodiment as well. The piezoelectric shoulder 40 is hermetically connected to the actuator 50. The actuator 50 may be of any suitable well-known type, but a variable voltage source for dynamically varying the voltage over a continuous range of voltages is shown by way of example. One skilled in the art will appreciate that the energy level of the light signal at the output of either the waveguide 20 or the 30 is controlled dynamically, in proportion to the voltage level supplied by the actuator 50.

This being the case, the variable alternator 10 is put into practice, varying the voltage over a continuous interval. The operation of the variable alternator 10 according to the invention, as shown in Figure 9, is as follows. As discussed with respect to the first embodiment, if the piezoelectric shoulder 40 is de-energized, the light signal propagating in a symmetrical Mach-Zehnder 100 device will be addressed to the output of the waveguide 30. When it receives a command signal which commands that the light output of the waveguide 30 be attenuated at a certain level, the network interface 60 interprets the command signal and translates it to the voltage level within the range provided by the actuator 50. The actuator 50 supplies the piezoelectric shoulder 40 with the voltage level, as ordered. In response, the piezoelectric shoulder 40 expands and deforms the waveguide structure 20, causing it to change the refractive index and the length of the waveguide 20. If so, a portion of the light signal is diverted from the output of the waveguide 30 and redirected to the output of the waveguide 20. As the voltage increases, most of the signal from the waveguide 30 is deflected and attenuated thereby. When the actuator 50 supplies the predetermined voltage to the piezoelectric shoulder 40, a phase difference of p radians is established between the waveguide 20 and the waveguide 30. In that state, the output of the waveguide is completely attenuated. Thus, the voltage supplied by the actuator 50 is proportional to the amount of attenuation.

In still another alternative embodiment, as is modalized herein and as shown in Fig. 10, a scheme of the piezoelectric adjustable filter 10 includes a Mach-Zehnder device 100 formed by the waveguide 20 and the waveguide 30. Note that the waveguide 20 is shorter than the waveguide 30 by a distance? L = L2-L ?, which is approximately 200 μm. The piezoelectric shoulder 40 is disposed on the waveguide structure 20 at a distance offset from the waveguide core 22. The discussion of the deviated distance with respect to FIG. 2 equally applies to this embodiment as well. The piezoelectric shoulder 40 is electrically connected to the actuator 50. The operation of the adjustable filter 10 according to the invention, as shown in FIG. 10, is as follows. The phase variation between the two branches is given by the following equation: AF = ^ nAL (H)? Since the refractive index n is dependent on the wavelength, the product n? L is also dependent on the wavelength. For a large L, a large phase difference between different wavelengths can be obtained. For example, in a first drive state in which a piezoelectric shoulder 40 is not operated, there is no phase difference for the light at? I = 1554.5 nm and there is a phase difference p for the light at? 2 = 1558.5 nm. If so, will not it interfere with? -i, while that? 2 will experience destructive interference. In a second actuation state, the piezoelectric projection 40 induces a phase difference p between the waveguide 20 and the waveguide 30. Due to the dependence of the wavelength described above, the attenuation at the different wavelengths will change and? 2 will not be interfered with and? i will be destroyed by destructive interference. Figures 11A-Q are sequential schematic views of the piezoelectric optical switch of the present invention in successive stages of manufacture. In Figure 11A the substrate 100 is formed. The substrate 100 can be of any known type, although a substrate formed of silicon glass is shown by way of example. Figure 11B shows a buffer layer 112 which is deposited on the substrate 100. The buffer layer 112 can be of any known type, although a layer formed of silica glass is shown by way of example. Figure 11C shows a core layer 114 that is deposited on the buffer layer 112. The core layer 114 can be of any known type, although a layer formed of silica glass having a shrinkage index is shown by way of example. n, greater than that of the buffer layer 112. The person skilled in the art will appreciate that the manufacturing steps described in Figures 11A and 11C can also be carried out using polymers, copolymers, monomers or other suitable materials. Figures 11 D and 11 H show the photolithographic procedure for forming the waveguide structure 20 and waveguide structure 30. mask 116 is placed on core layer 114 and the pattern of waveguide structures 20 and 30 is transferred to core layer 114 by illumination of the mask. The etching procedure shown in Figure 11G removes excess core material. In Figure 11 H the coated layer 24 is deposited on waveguide structures 20 and 30. Figures 11 I-11 N show a piezoelectric ledge 40 which is formed on the waveguide structure 20. A layer of PZT or ZnO is deposited on the lower electrode 44. The dimensions of the PZT shoulder will vary within the ranges provided in the above description. In Figure 11 P the spiral cables 18 are connected to waveguides 20 and 30 to provide optical connectivity. Finally, in Figure 11Q, the piezoelectric shoulder electrodes are connected to a connector placed in the optical packaging unit 118. It will be apparent to those skilled in the art that various modifications and variations to the present invention can be made without departing from the spirit. and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they fall within the scope of the appended claims and their equivalents.

Claims (67)

1. NOVELTY OF THE INVENTION CLAIMS 1. - An optical device for selectively directing a light signal to a first output or a second output, said optical device comprising: at least one waveguide having at least one core connected to the first output, the propagation of light signal together with at least one waveguide in the direction of propagation; and at least one piezoelectric element for switching the light signal from the first output to the second output by inducing a plurality of mutually orthogonal stress components in at least one waveguide, at least one piezoelectric element being disposed on at least one waveguide in a predetermined position such that there is substantially in at least one core only a first component of the plurality of mutually orthogonal stress component, wherein the first component is a stress component aligned with the propagation direction.
2. 2. The optical device according to claim 1, further characterized in that the predetermined position produces a birefringence value in said core that has to be substantially insignificant.
3. 3. The optical device according to claim 1, further characterized in that said waveguide comprises a first waveguide and a second waveguide through which it forms an optical coupler.
4. 4. The optical device according to claim 1, further characterized in that said waveguide comprises a first waveguide and a second waveguide by means of which a Mach-Zehnder device is formed. 5.- An optical Mach-Zehnder device to direct a light signal that has a wavelength? in a first output or a second output, said optical device comprises: a first waveguide having a first core connected to the first output, a refractive index n, a first length L |, and a first output, the signal of light propagates in said first core in the direction of propagation; and a first piezoelectric shoulder for switching the light signal between the first output and the second output creating a first plurality of mutually orthogonal stress components at the first wavelength, the first piezoelectric shoulder is placed on the first wavelength of a predetermined deviation distance of said first core such that there is substantially in the first core only a first component in the first plurality of mutually orthogonal stress components, wherein the first component is parallel to the propagation direction. 6. The optical device according to claim 5, further characterized in that the first predetermined position produces a birefringence value in the first core that has to be substantially insignificant. 7. The optical device according to claim 5, further comprising: a second wave line placed adjacent to the first waveguide having a second core connected to the second output, the refractive index n, and a second length L2, wherein said second core propagates the light signal in the direction of propagation; and a first actuator connected to the first piezoelectric shoulder to cause the first piezoelectric shoulder to produce a first waveguide deformation, said first waveguide deformation produces the first plurality of mutually orthogonal stress components in the first waveguide. 8. The optical device according to claim 7, further characterized in that the first waveguide deformation induces a phase difference between the first waveguide and the second waveguide, said phase difference being characterized by the equation : where dn is a change in the refractive index n and d ^ is a change in the length L |. 9. The optical device according to claim 5, further characterized in that the light signal comprises a first polarized component in one x direction and a second polarized component in one direction y, wherein the x direction, the y direction, and the z direction are mutually orthogonal axes of a rectangular coordinate system, and the z direction is in the direction of propagation. 10. The optical device according to claim 9, further characterized in that the first plurality of mutually orthogonal force components is related to a change in the refractive index n, by the equations: d and «-y (pl2? + pney + p12e2) where dnx is a change in the refractive index for the first polarized component, dny is a change in the refractive index for the second polarized component, pn and p-? 2 are photoelastic coefficient, and ex, ey and ez = dL ? / L- ?, are the first plurality of mutually orthogonal stress components and dLi is a change in the first length L |. 11. The optical device according to claim 10, further characterized in that the first waveguide deformation establishes a first phase change of polarized component? FX, a second phase change of polarized component? Fy, between the first guide of wave and the second waveguide according to the equations: 2ttL,? F, = - ^ y, 2tzL, where Kx and Ky are non-dimensional coefficients and functions of the first plurality of mutually orthogonal stress components. 12. The optical device according to claim 10, further characterized in that a first birefringence value in the first core is related to the plurality of mutually orthogonal stress components by means of the expression: dn, + dn. Q = dnr - dn ,, where Q is inversely proportional to the first birefringence value. 13. The optical device according to claim 12, further characterized in that the first offset distance default is approximately equal to? / 4n. 14. - The optical device according to claim 12, further characterized in that the first and second outputs have an extinction ratio that has at least 20 dB when Q is greater than 16. 15. The optical device according to claim 5, further characterized in that the first waveguide deformation establishes a phase difference of p radians between the first waveguide and the second waveguide causing the light signal to be directed towards the first output. 16. The optical device according to claim 15, further characterized in that the light signal is directed towards the second output when there is no first waveguide deformation. 17. The optical device according to claim 15, further characterized in that the first actuator is a voltage source connected to the first piezoelectric shoulder to supply a predetermined voltage to the first piezoelectric shoulder. 18. The optical device according to claim 15, further characterized in that the first piezoelectric shoulder has a first shoulder length Lp, which corresponds to the phase change of p radians according to the equation: £ "- - where Kx and Ky are non-dimensional coefficients and a function of the first plurality of mutually orthogonal stress components. 19. The optical device according to claim 18, further characterized in that Lp is approximately in the range of 2 mm to 3 cm. 20. The optical device according to claim 18, further characterized in that the width of the first piezoelectric shoulder is approximately in the range of 20 μm to 300 μm. 21. The optical device according to claim 18, further characterized in that the thickness of the first piezoelectric shoulder is in the range of about 3 μm to 300 μm. 22. The optical device according to claim 5, further comprising: a second piezoelectric shoulder for switching the light signal between the first output and the second output in accordance with the first piezoelectric shoulder creating a second plurality of mutually orthogonal stress components in the second waveguide, said second piezoelectric shoulder it is placed on the second waveguide at a second predetermined distance deviated from the second core so that only a second component of the second plurality of mutually orthogonal stress components exists substantially in the second core where the second component is parallel to the direction propagation; and a second actuator connected to the second piezoelectric shoulder to cause the second piezoelectric shoulder to generate a second waveguide deformation, said second waveguide deformation produces the second plurality of mutually orthogonal stress components in the second waveguide. 23. The optical device according to claim 22, further characterized in that the first length Li is substantially equal to the second length L2. 24. The optical device according to claim 23, further characterized in that the first waveguide deformation is caused by supplying the first actuator with a first predetermined voltage and the second waveguide deformation is caused to supply the second actuator. with a second predetermined voltage having a plurality opposite said first predetermined voltage. 25. The optical device according to claim 24, further characterized in that the first waveguide deformation establishes a first phase change in the first waveguide and the second waveguide deformation establishes a second phase change in the second waveguide, where a phase difference between the phase change and the second phase change is approximately equal to radians or to an odd multiple of p radians. 26. The optical device according to claim 23, further characterized in that there is a phase difference of approximately zero radians when the first waveguide and the second Waveguide are not deformed and the light signal is directed towards the second output. 27. The optical device according to claim 23, further characterized in that a length of the first piezoelectric shoulder and a length of the second piezoelectric shoulder are equal and have a shoulder length L (p / 2) which corresponds to a change of p / 2 radians according to the equation: to? £ & 2 '- (KX + K where a is a constant of proportionality approximately equal to 0.5,? is the wavelength, Kx and Ky are non-dimensional coefficients related to the first plurality of mutually orthogonal stress components and the second plurality of mutually orthogonal stress components in the first waveguide and the second waveguide, respectively. 28. The optical device according to claim 22, further characterized in that the first length Li and the second length L2 are not equal, form a path length difference that establishes a phase difference of p radians between the first guide of wave and the second waveguide. 29. - The optical device according to claim 22, further characterized in that the first length Li and the second length L2 are not equal, forming a path length difference that establishes a phase difference of p / 2 radians between the first guide of wave and the second waveguide. 30. The optical device according to claim 29, further characterized in that the difference in the path length is approximately 250 nm. 31. The optical device according to claim 28, further characterized in that the first waveguide deformation is caused by supplying the first actuator with a positive predetermined voltage and the second waveguide deformation is caused by supplying the second actuator. with a negative predetermined voltage. 32. The optical device according to claim 31, further characterized in that the first waveguide deformation induces a phase change of approximately + p / 4 in the first waveguide and the second waveguide deformation induces a phase change of about -p / 4 in the second waveguide causing a phase difference of p radians between the first waveguide structure and the second waveguide structure in such a way that the light signal is directed towards the first exit. 33. The optical device according to claim 31, further characterized in that the first waveguide deformation is caused by supplying the first actuator with a predetermined negative voltage and the second waveguide deformation is caused by supplying the second actuator with a positive predetermined voltage. 34.- The optical device according to claim 33, further characterized in that the first waveguide deformation induces a phase change of about -p / 4 in the first waveguide structure and the second waveguide deformation induces a phase change of approximately + p / 4 is the second waveguide structure that causes a cancellation of the phase difference p / 2 radians between the first waveguide and the second waveguide established by the difference in length of track through which the light signal is directed towards the second exit. 35. The optical device according to claim 31, further characterized in that the first waveguide and the second waveguide are not deformed causing the light signal to be divided into substantially equal portions that are directed to the first output. and the second exit. 36.- The optical device according to claim 31, further characterized in that the first piezoelectric shoulder and the second piezoelectric shoulder have a shoulder length L (p / 4) corresponding to a change of p / 4 radians in accordance with the equation: where a is a constant of proportionality approximately equal to 0.25 and Kx and Ky are non-dimensional coefficients related to the first plurality of mutually orthogonal stress components and the second plurality of mutually orthogonal stress components in the first waveguide and the second waveguide, respectively. 37. The optical device according to claim 22, further characterized in that the first piezoelectric shoulder comprises: a first outer piezoelectric strip positioned on an outer side of the waveguide with the distance substantially equal to the first offset; and a first internal piezoelectric strip positioned on an inner side of the first waveguide with the distance substantially equal to the first offset. 38.- The optical device according to claim 37, further characterized in that the second piezoelectric shoulder comprises: a second outer piezoelectric strip positioned on an outer side of the second waveguide structure with the distance substantially equal to the second offset; and a second inner piezoelectric strip positioned on an inner side of the second waveguide being the distance substantially equal to the second offset, wherein the distance between the first inner piezoelectric strip and the second inner piezoelectric strip is substantially within a range between 500 microns to 1,000 microns. 39. - The optical device according to claim 5, further characterized in that the first actuator is a voltage source variable connected to the first piezoelectric ledge to supply a voltage proportional to a quantity of light signal that is directed to the first output. 40.- The optical device according to claim 39, further characterized in that the voltage is variable in a continuous range between zero volts and a first predetermined amount of voltage. 41. The optical device according to claim 40, further characterized in that zero volts correspond to a maximum attenuation of the light signal and the first predetermined voltage amount corresponds to a maximum transmission of the light signal. The optical device according to claim 5, further comprising a slot engraved with acid between the first outlet and the second exit to mechanically isolate the first exit from the second exit. 43.- The optical device according to claim 5, further characterized in that the first length L-i and the second length L2 they have approximately a difference in track length of 200 microns, said difference in path length induces a phase variation equal to: 2p? F = - nAL? where? L is equal to L L2. 44. - The optical device according to claim 43, further characterized in that a first light signal having a first wavelength is output when the first piezoelectric projection is not operated, and a second light signal having a second wavelength it is released when the first piezoelectric shoulder is actuated. 45.- A method to direct a light signal that has a wavelength? towards a first output or a second output of an optical device including a first waveguide having a first core connected to the first output, a refractive index n, a first length Li, where the light signal propagates through means of the first core in a propagation direction, said method for directing a light signal comprises the steps of: providing a first piezoelectric shoulder to generate a first plurality of mutually orthogonal stress components in the first waveguide, the first piezoelectric shoulder it is placed on the first waveguide at a predetermined deviation distance from the first core such that there is substantially in the first core only a first component of the first plurality of mutually orthogonal stress components, wherein the first component is parallel to the direction of propagation; providing a second waveguide placed adjacent to the first waveguide having a second core connected to the second output propagating the light signal in the propagation direction, the refractive index n, and a second length L2, and a second exit; and trigger the first piezoelectric projection by means of which a first waveguide deformation is generated producing the first plurality of mutually orthogonal stress components that will occur in the first waveguide. 46. The method according to claim 45, further characterized in that the step of driving the first piezoelectric shoulder induces a phase difference of p radians between the first waveguide and the second waveguide. 47. The method according to claim 45, further characterized in that the light signal leaves the second waveguide structure when the step of driving the first piezoelectric shoulder has not been carried out. 48. The method according to claim 45, further comprising the steps of: providing a second piezoelectric shoulder to generate a second plurality of mutually orthogonal stress components in the second waveguide, the second piezoelectric shoulder is placed over the second waveguide at a second predetermined deviation distance from the second core such that there exists only in the second core a second component of the second plurality of mutually orthogonal stress components, wherein said second component is parallel to the direction of propagation; and actuating said second piezoelectric projection by means of which a second waveguide deformation is generated generating said second plurality of mutually orthogonal stress components that will occur in the second waveguide. 49. The method according to claim 48, further characterized in that the step of driving the first piezoelectric shoulder includes supplying the first piezoelectric shoulder with a positive predetermined voltage and the step of driving the second piezoelectric shoulder includes supplying the second piezoelectric shoulder with a negative predetermined voltage. 50.- The method according to claim 49, further characterized in that the step of actuating the first piezoelectric shoulder establishes a phase change of approximately -p / 2 radians in the first waveguide structure and the step of actuating the second Piezoelectric rise establishes a phase change of approximately -p / 2 radians in the second waveguide structure. 51.- The method according to claim 49, further characterized in that a phase difference of p radians or an odd multiple of p radians is established between the first waveguide and the second waveguide causing the light signal to be directed towards the first output. 52. The method according to claim 48, further characterized in that there is no phase difference established between the first waveguide and the second waveguide when the first waveguide The wave and the second waveguide are not deformed, and the light signal is directed towards the second output. 53. The method according to claim 48, further characterized in that the first length Li and the second length L2 are unequal and have a path length difference that generates approximately a phase difference of p / 2 radians between the first structure waveguide and the second waveguide structure. 54. The method according to claim 53, further characterized in that the step of actuating the first piezoelectric shoulder includes supplying the first piezoelectric shoulder with a predetermined positive voltage causing the light signal to which the phase will be changed to be of about + p / 4 radians in the first waveguide structure, and the step of driving the second piezoelectric shoulder includes supplying the second piezoelectric shoulder with a negative voltage causing the light signal to be phase shifted to be approximately -p / 4 radians in the second waveguide structure. The method according to claim 32, further characterized in that there is a phase difference of p radians or an odd multiple thereof between the first waveguide structure and the second waveguide structure causing the signal of light leave the optical device from the first waveguide structure. 56. - The method according to claim 53, further characterized in that the step of actuating the first piezoelectric shoulder includes supplying the first piezoelectric shoulder with a predetermined negative voltage causing the light signal to be phase-shifted to be approximately -p / 4 radians in the first waveguide structure and, the step of actuating the second piezoelectric shoulder includes supplying the second piezoelectric shoulder with a positive voltage causing the light signal to be changed to be approximately + p / 4 radians in the second waveguide structure. 57.- The method according to claim 56, further characterized in that the p / 2 is canceled and there is no phase difference between the first waveguide and the second waveguide and the light signal is directed towards the second departure. 58.- The method according to claim 53, further characterized in that the step of driving the first piezoelectric shoulder and the step of driving the second piezoelectric shoulder are not carried out causing the light signal to be divided into substantially equal portions of way to the first exit and the second exit, respectively. 59.- A method for manufacturing an optical device on a substrate, said optical device is used to direct a light signal, said manufacturing method comprises the steps of: placing a core layer waveguide on the substrate and form a first waveguide from said waveguide core layer, wherein the first waveguide structure includes a first core, a refractive index n, and a first length Li: forming a second waveguide structure of the waveguide core layer wherein the second waveguide structure includes a second core, a refractive index n, and a second length Li; placing a first piezoelectric ledge on the first waveguide structure at a first predetermined deviation distance from said first core, wherein the first predetermined deviation distance minimizes a birefringence value in the first waveguide at a second distance of predetermined deviation of said second core, wherein the second predetermined deviation distance minimizes a birefringence value in the second waveguide. The method according to claim 59, further characterized in that the step of placing a first piezoelectric shoulder further comprises: placing a first outer piezoelectric strip on an outer side of the first waveguide structure being the distance substantially equal to the first deviation; and placing a first inner piezoelectric strip on an inner side of the first waveguide with the distance substantially equal to the first offset. 61.- The method according to claim 60, further characterized in that the step of placing a second piezoelectric shoulder further comprises: placing a second piezoelectric strip outer on an outer side of the second waveguide structure with the distance substantially equal to the deviation; and placing a second inner piezoelectric strip on an inner side of the second waveguide with the distance substantially equal to the deviation. 62. The method according to claim 61, further characterized in that the first piezoelectric outer strip, the second external piezoelectric strip, the first inner piezoelectric strip, and the second inner piezoelectric strip each with a width substantially in the range between 50 mieras and 200 mieras. 63. The method according to claim 62, further characterized in that a distance between the first inner piezoelectric strip and the second inner piezoelectric strip is substantially in the range between 500 microns and 3,000 microns. 64.- The method according to claim 59, further characterized in that the first piezoelectric shoulder or the second piezoelectric shoulder or both are made of a piezoelectric material prepared with a substance or substances that are selected from the group consisting of: zirconate-titanate of lead (PZT) or zinc oxide (ZnO). The method according to claim 59, further characterized in that the first waveguide structure or the second waveguide structure or both are made of a material prepared with a substance or substances selected from the group consisting of: silica , polymers or copolymers. 66. - The method according to claim 59, further characterized in that the first waveguide structure has a first cross-sectional shape and the second waveguide structure has a second cross-sectional shape, wherein the first sectional shape The cross section and the second cross sectional shape are either square, rectangular, trapezoidal, circular or semicircular. 67.- A method for selectively directing a light signal in a first output or a second output of an optical device that includes at least one wavelength having at least one core connected to the first output, wherein the signal of Light propagates along said waveguide in a propagation direction, said method for selectively directing a light signal comprises the steps of: providing at least one piezoelectric element for switching the light signal from the first output to the second output inducing a plurality of mutually orthogonal stress components in said waveguide, at least one piezoelectric element is placed on said waveguide at a predetermined position such that only a first component of said plurality of components exists substantially in said core. of mutually orthogonal stress, wherein the first component is a stress component aligned to said direction propagation ion; and actuating at least one piezoelectric element by means of which a deformation is generated in said waveguide causing said plurality of mutually orthogonal stress components occur in said waveguide.