Active interference reduction in pockels cells

Abstract

To provide an additional piezoelectric component that generates acoustic compensation of an electro-optic modulator (EOM) for use in the Long-Wave Infrared (LWIR) spectrum and Mid-Wave Infrared (MWIR) spectrum.SOLUTION: A system and method is disclosed, for providing an additional piezoelectric component that generates acoustic compensation of an electro-optic modulator (EOM) for use in the Long-Wave Infrared (LWIR) spectrum and Mid-Wave Infrared (MWIR) spectrum.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and benefit of U.S. Provisional Patent Application No. 63 / 552,506, filed February 12, 2024, entitled "ACTIVE ACOUSTIC COMPENSATION OF EOM FOR USE IN LWIR AND MWIR SPECTRUM," which is hereby incorporated by reference in its entirety. [Background technology]

[0002]

[0002] The limitations and drawbacks of conventional electro-optic modulators (EOMs) will become apparent to those skilled in the art upon comparing such approaches with certain aspects of the present method and system described in the remainder of this disclosure with reference to the drawings. Summary of the Invention

[0003]

[0003] The system and method provide additional piezoelectric components that produce acoustic compensation of electro-optic modulators (EOMs) for use in the long-wave infrared (LWIR) and mid-wave infrared (MWIR) spectrum, substantially as shown by and / or described in connection with at least one of the figures, and more fully as set forth in the claims. [Brief explanation of the drawings]

[0004] [Figure 1]

[0004] FIG. 1 illustrates an exemplary EOM without additional piezoelectric components, according to various exemplary embodiments of the present disclosure. [Figure 2]

[0005] FIG. 1 illustrates a first example EOM system with an additional piezoelectric component for active compensation of acoustic interference generated by a Pockels cell, according to various example embodiments of the present disclosure. [Figure 3]

[0006] FIG. 10 illustrates a second example EOM system with an additional piezoelectric component for active compensation of acoustic interference generated by a Pockels cell, in accordance with various example embodiments of the present disclosure. [Figure 4]

[0007] FIG. 10 illustrates a third example EOM system with an additional piezoelectric component for active compensation of acoustic interference generated by a Pockels cell, in accordance with various example embodiments of the present disclosure. [Figure 5]

[0008] FIG. 10 illustrates a fourth example EOM system with an additional piezoelectric component for active compensation of acoustic interference generated by a Pockels cell, according to various example embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0005]

[0010] The following description provides various examples of systems and methods for producing piezoelectric components for active compensation. Such examples are non-limiting, and the scope of the appended claims should not be limited to the particular examples disclosed. In the following description, the terms "example" and "for example" are non-limiting.

[0006]

[0011] The figures show general schemes of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the present disclosure. Additionally, elements in the depicted figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of the examples discussed in this disclosure. The same reference numbers in different figures represent the same elements.

[0007]

[0012] The term "or" means any one or more of the items in the list connected by "or." As an example, "x or y" means any element of the 3-element set {(x),(y),(x,y)}. As another example, "x, y, or z" means any element of the 7-element set {(x),(y),(z),(x,y),(x,z),(y,z),(x,y,z)}.

[0008]

[0013] The terms "comprises," "comprising," "includes," and / or "including" are "open-ended" terms that specify the presence of stated features but do not exclude the presence or addition of one or more other features.

[0009]

[0014] Terms such as "first," "second," and the like may be used herein to describe various elements, but these elements should not be limited by these terms. These terms are used only to distinguish one element from another. Thus, for example, a first element discussed in this disclosure could be referred to as a second element without departing from the teachings of the disclosure.

[0010]

[0015] Unless otherwise specified, the term "coupled" may be used to describe two elements that are in direct contact with each other or two elements that are indirectly connected by one or more other elements. For example, if element A is coupled to element B, element A may be in direct contact with element B or indirectly connected to element B by an intervening element C. Similarly, the terms "over" or "on" may be used to describe two elements that are in direct contact with each other or two elements that are indirectly connected by one or more other elements.

[0011]

[0016] Light is a fundamental phenomenon with diverse properties and applications that span the electromagnetic spectrum, from radio waves to gamma rays. While the human eye perceives only the visible spectrum, light extends beyond this range and includes longer wavelengths, such as infrared, and shorter wavelengths, such as ultraviolet and X-rays. These wavelength differences correspond to changes in energy, provide unique interactions with materials, and enable specialized technologies. For example, long-wave infrared (LWIR) light is characterized by lower energy and longer wavelengths compared to visible light and plays an important role in areas such as imaging, industrial processing, and advanced optics.

[0012]

[0017] An important attribute of light is its polarization, the orientation of its electric field in space. Polarization can appear as linear, circular, or elliptical, depending on the light wave's interaction with materials or filters. This property is particularly important when dealing with coherent light sources such as lasers, which propagate in a fixed direction and exhibit consistent wavelengths and polarizations. Being able to manipulate polarization can enable precise control over light for applications such as optical switching and modulation.

[0013]

[0018] The electro-optic effect, specifically the Pockels effect, is central to the operation of electro-optic modulators (EOMs), which enable dynamic control of light polarization. This effect occurs in certain non-centrosymmetric crystals, where an applied electric field causes a change in the refractive index, altering the polarization state of the transmitted light. Materials such as cadmium telluride (CdTe), gallium arsenide (GaAs), zinc selenide (ZnSe), zinc sulfide (ZnS), cadmium zinc telluride (CdZnTe or CZT), and boron arsenides (BAs) are among the few materials capable of supporting this effect in the LWIR and mid-wave infrared (MWIR) spectrum due to their unique optical and structural properties.

[0014]

[0019] Pockels cells, the key component of EOMs, utilize these electro-optic materials to modulate light at high speeds without moving parts. By applying a voltage across the crystal, the birefringence of the material can be controlled, which can enable phase modulation of a laser beam with nanosecond precision. This capability is important in advanced applications such as extreme ultraviolet (EUV) lithography, where precise timing and modulation of light is essential to producing cutting-edge microchips.

[0015]

[0020] This disclosure relates to electro-optic modulators (EOMs), and more particularly to methods and systems for reducing acoustic interference caused by piezoelectric effects in EOMs. Such interference can reduce modulation efficiency and affect system performance. This disclosure describes a mechanism for counteracting these acoustic effects by using additional piezoelectric components for active compensation.

[0016]

[0021] FIG. 1 illustrates an exemplary EOM 100 without additional piezoelectric components, according to various exemplary embodiments of the present disclosure. The basic principle of an EOM such as that illustrated in FIG. 1 relies on a change in an electric field applied across an electro-optic crystal 101 via electrodes 103 and 105. When subjected to an electric field, the electro-optic crystal 101 exhibits a birefringence effect on transmitted light, which can allow modulation. Materials that exhibit the electro-optic effect may be characterized by a non-zero electro-optic coefficient in their electro-optic tensor. However, when placed in an electric field, such materials inherently exhibit a piezoelectric effect and generate undesired acoustic waves.

[0017]

[0022] These acoustic waves induce stress in the crystal 101, which can result in stress-induced birefringence effects that reduce modulation efficiency, especially the extinction coefficient of the Pockels cell. The interaction between acoustic and electro-optic effects is responsible for a phenomenon called "acoustic ringing," which affects the performance and accuracy of EOMs.

[0018]

[0023] This disclosure introduces systems and methods for mitigating acoustic interference in EOMs by utilizing additional piezoelectric components strategically oriented to cancel or attenuate acoustic waves generated by the electro-optic crystal. Active acoustic cancellation is achieved by opposing acoustic or electric waves, thereby reducing the adverse effects of acoustic ringing.

[0019]

[0024] When a voltage is applied across the electro-optic crystal 101, it induces a piezoelectric response, causing the crystal to contract in one direction and expand in another. This deformation generates acoustic waves that propagate through the assembly and resonate at specific frequencies. These resonances, or "ringing," occur at characteristic frequencies (e.g., 41 kHz) and adversely affect modulation efficiency.

[0020]

[0025] The present disclosure can utilize additional piezoelectric components (e.g., piezoelectric crystals, piezoelectric ceramics, and / or piezoelectric polymers) to counteract these acoustic effects. The system generates counteracting acoustic or compensating electrical waves that neutralize the undesired effects. An embodiment is shown in Figures 2-5.

[0021]

[0026] FIG. 2 illustrates a first example EOM system 200 with an additional piezoelectric component 201 for active compensation of acoustic interference generated by a Pockels cell, according to various example embodiments of the present disclosure.

[0022]

[0027] In the single piezoelectric component configuration of Figure 2, a piezoelectric component 201 is placed between the electro-optic crystal 101 and one of the electrodes 105. This component 201 is configured to generate a compensating wave to cancel the acoustic interference.

[0023]

[0028] FIG. 3 illustrates a second example EOM system 300 with additional piezoelectric components for active compensation of acoustic interference generated by the Pockels cell, according to various example embodiments of the present disclosure.

[0024]

[0029] In the dual piezoelectric component configuration of FIG. 3, two piezoelectric components 201 and 301 are positioned on either side of the electro-optic crystal 101 to allow for symmetrical attenuation of acoustic waves.

[0025]

[0030] FIG. 4 illustrates a third example EOM system 400 with additional piezoelectric components for active compensation of acoustic interference generated by a Pockels cell, according to various example embodiments of the present disclosure.

[0026]

[0031] In the stacked electrode configuration of FIG. 4, a piezoelectric component 201 is inserted between one of the electrodes 105 and an additional electrode 401, allowing for a configuration optimized for acoustic attenuation.

[0032] FIG. 5 illustrates a fourth example EOM system 500 with additional piezoelectric components for active compensation of acoustic interference generated by the Pockels cell, according to various example embodiments of the present disclosure.

[0027]

[0033] In the enhanced damping configuration of Figure 5, additional piezoelectric components 501 and 503 are fabricated from the same material as electro-optic crystal 101 to allow perfect acoustic matching. The crystal orientations of these components may be different to maximize damping effectiveness.

[0028]

[0034] To achieve the damping, the piezoelectric components can be powered and synchronized with the primary modulation system. In some implementations, the components can be driven by the same electric field used for the primary modulation to enable synchronization. Alternatively, a separate control system can be utilized to generate a specially adapted compensation signal. Using the same material for the piezoelectric and electro-optic components can facilitate matching of acoustic properties, further improving performance.

[0029]

[0035] The present disclosure allows flexibility in material selection, provided the material exhibits the piezoelectric effect and can be properly cut, oriented, and bonded. Gallium arsenide, for example, is an ideal candidate due to its excellent electro-optic and piezoelectric properties. Gallium arsenide stacks can enable acoustic compatibility and optimal performance when additional piezoelectric components are layered with the electro-optic crystal.

[0030]

[0036] Compared to existing long-wavelength infrared EOMs, the disclosed systems and methods can offer significant advantages. They can improve modulation efficiency. For example, active damping can eliminate stress-induced birefringence effects, resulting in sharper turn-on and turn-off transitions.

[0031]

[0037] Reducing acoustic resonance can minimize component wear and improve system life. The system design can handle higher power levels without performance degradation. EOMs can involve unknown voltage inputs that can be determined according to the phase shift.

[0032]

[0038] The present disclosure provides a solution to the challenges posed by acoustic interference in EOMs. By utilizing additional piezoelectric components and active acoustic cancellation techniques, the disclosed systems and methods can improve modulation efficiency, durability, and power handling while ensuring clean and precise operation.

[0033]

[0039] The systems and methods of the present disclosure can provide automatic adjustment of the canceling acoustic waves according to feedback from the stress sensors. Additionally, the systems and methods can include a delay circuit configured to time the canceling acoustic waves.

[0034]

[0040] While the present method and / or system has been described with reference to specific embodiments, it will be understood by those skilled in the art that various modifications may be made and equivalents may be substituted without departing from the scope of the present method and / or system. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from its scope. Therefore, it is not intended that the present method and / or system be limited to the particular embodiments disclosed, but rather that the present method and / or system will include all embodiments falling within the scope of the appended claims.

Claims

1. a nonlinear electro-optic crystal; A plurality of electrodes; a piezoelectric component operably coupled to the plurality of electrodes; Including, the piezoelectric component is configured to generate canceling acoustic waves to reduce interference associated with the nonlinear electro-optic crystal; system.

2. The system of claim 1 , wherein the piezoelectric component comprises the same material as the nonlinear electro-optic crystal.

3. 10. The system of claim 1, comprising two piezoelectric components disposed on opposite sides of the nonlinear electro-optic crystal.

4. 10. The system of claim 1, wherein the canceling acoustic waves are configured to be adaptively adjusted according to a desired attenuation.

5. The system of claim 1 , wherein the piezoelectric component is aligned according to a crystal orientation of the nonlinear electro-optic crystal.

6. 10. The system of claim 1, wherein the electrodes are thermally isolated to prevent material degradation.

7. 10. The system of claim 1, wherein the adjustment of the canceling acoustic waves is automated via feedback from a stress sensor.

8. 10. The system of claim 1, comprising a delay circuit configured to time the canceling acoustic waves.

9. 10. The system of claim 1, wherein the piezoelectric component is a multiphase composite configured for damping.

10. The system of claim 1 , wherein the plurality of electrodes are stacked in layers to improve waveform distribution.

11. Positioning a piezoelectric component adjacent to an electro-optic crystal; modulating the piezoelectric component with a waveform; A method comprising:

12. The method of claim 11 , wherein the piezoelectric component comprises the same material as the electro-optic crystal.

13. The method of claim 11 , wherein the system includes two piezoelectric components disposed on opposite sides of the electro-optic crystal.

14. 12. The method of claim 11, the waveform is a cancelling acoustic wave; The method includes adaptively adjusting the canceling acoustic waves according to a desired attenuation.

15. 12. The method of claim 11, comprising aligning the piezoelectric component according to a crystal orientation of the electro-optic crystal.

16. 12. The method of claim 11, the piezoelectric component is operably coupled to a plurality of electrodes; the electrodes are thermally isolated to prevent material degradation; method.

17. 12. The method of claim 11, the waveform is a cancelling acoustic wave; The method includes adaptively adjusting the canceling acoustic waves according to feedback from a stress sensor. method.

18. 12. The method of claim 11, including timing the waveform through a delay circuit.

19. 12. The method of claim 11, wherein the piezoelectric component is a multiphase composite configured for damping.

20. 12. The method of claim 11, the piezoelectric component is operably coupled to the plurality of electrodes; The electrodes are stacked in layers to improve the distribution of the waveform. method.

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