A multifunctional acoustic double-sided mirror

Abstract

This application provides a multifunctional acoustic double-sided mirror, comprising: multiple groove structures and multiple parity-time structures; wherein the groove structures and parity-time structures are connected in series, and in the series structure, the groove structures and parity-time structures are distributed in a staggered manner. Each groove structure has two grooves, upper and lower, and the two grooves and the parity-time structures together constitute the upper and lower surfaces of the double-sided mirror. The upper and lower surfaces have different reflection phase gradient modulations, and the upper and lower surfaces of the double-sided mirror structure have different modulation performances for sound waves. This application has a simple design, can be incident over a wide angle range, and different surface acoustic wave incidents have different wave modulation capabilities; the structure also has ventilation performance.

Description

Technical Field

[0001] This application relates to the field of acoustic device technology, and in particular to a multifunctional acoustic double-sided mirror. Background Technology

[0002] Next-generation advanced acoustic devices require a high degree of functionality, especially for medical ultrasound reflective lenses, which often need to switch between multiple functions, thus placing high demands on the acoustic devices. Existing acoustic mirror structures usually exhibit the same sound wave diffraction phenomenon on both sides of the mirror structure, making it difficult to support functional diversity. How to design a mirror structure that can achieve different diffraction effects on both sides is of great significance for the design of next-generation multifunctional acoustic devices. For example, when a sound wave is incident on one side of the structure, it will be reflected along its original path, while when it is incident on the other side, it will undergo specular reflection.

[0003] Existing technologies cannot achieve different diffraction effects with different incident directions when the structures on both sides are identical, unless a complex structural combination is used. Different diffraction effects can only be achieved by incident light at different positions on the same side of the structure.

[0004] Existing technologies suffer from complex structural designs, significant thicknesses, and strong limitations on the incident angle. This is primarily due to design constraints and the sensitivity of the materials used to angle-dependent properties. Summary of the Invention

[0005] In view of this, the purpose of this application is to propose a multifunctional acoustic two-way mirror, which can specifically solve the existing problems.

[0006] To achieve the above objectives, this application proposes a multifunctional acoustic two-way mirror, comprising:

[0007] Multiple groove structures and multiple parity time structures;

[0008] The groove structure and the parity time structure are connected in series, and in the series structure, the groove structure and the parity time structure are distributed in a staggered manner.

[0009] Furthermore, each of the groove structures has two grooves, one above the other, and the two grooves together with the parity-time structure constitute the upper and lower surfaces of the double-sided mirror.

[0010] Furthermore, the upper and lower surfaces have different reflection phase gradient modulations, and the upper and lower surfaces of the double-sided mirror have different modulation properties for sound waves.

[0011] Furthermore, the upper surface has a phase gradient, while the lower surface has no phase gradient modulation.

[0012] Furthermore, when a sound wave is incident on the upper surface, it is entirely reflected back along its original path due to the phase gradient factor. When a sound wave is incident on the lower surface, half of the sound wave energy is reflected back along its original path, while the other half of the sound wave energy undergoes specular reflection.

[0013] Furthermore, the refractive index distribution of the parity-time structure satisfies .

[0014] Furthermore, the diffracted wave incident on the upper surface follows the formula ,in It is the phase gradient. It is the reciprocal lattice vector, p is the minimum cyclic period of the structure; n is the diffraction order. and Let the incident angle and the reflection angle be the incident angle and the reflection angle, respectively. For a diffracted wave incident on the lower surface, the following formula applies. .

[0015] Furthermore, this application also proposes an application of the multifunctional acoustic double-sided mirror according to any one of the above claims in the acoustic wave field and optical wave system.

[0016] In summary, the advantages of this application and the user experience it brings are as follows:

[0017] This application features a simple design that allows for incident light over a wide angle range (10°-65°), with different surface acoustic waves exhibiting varying wave modulation capabilities; the structure also possesses ventilation properties.

[0018] This application applies quantum-like effects to classical wave systems, combining a traditional acoustic grating structure with a PT structure, and for the first time considers the phase gradient modulation effect under the combination of classical structure and quantum-like effects. It achieves different acoustic wave modulation capabilities while maintaining consistent geometric dimensions on both sides of the structure. Furthermore, the structure is permeable, allowing air or fluid to pass through, which is helpful for specific applications, such as noise control where airflow is required to ensure heat dissipation. Attached Figure Description

[0019] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0020] Figure 1 A structural diagram of a multifunctional acoustic double-sided mirror according to an embodiment of this application is shown.

[0021] Figure 2 This is a schematic diagram illustrating the influence of structure parameter modulation on the parity-time structure.

[0022] Figure 3 This is a schematic diagram showing the evolution of the efficiency of different diffraction beams with respect to n' when surface acoustic waves are incident on the multifunctional acoustic double mirror of this application.

[0023] Figure 4 This is a schematic diagram showing the evolution of the efficiency of different diffraction beams with respect to n' when surface acoustic waves are incident on the multifunctional acoustic double mirror of this application.

[0024] Figure 5 This is a schematic diagram illustrating the effect of the multifunctional acoustic double-sided mirror structure of this application.

[0025] Reference numerals: 1: Groove structure; 2: Parity-time (PT) structure; 3: Sound wave incident on the upper surface; 4: Sound wave reflected back from the upper surface structure; 5: Sound wave reflected by the specular surface of the lower surface structure; 6: Sound wave incident on the lower surface; 7: Sound wave reflected back from the lower surface structure; 8: Upper surface with phase gradient modulation; 9: Lower surface without phase gradient modulation. Detailed Implementation

[0026] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] This application applies quantum-like effects to classical wave systems, combining a traditional acoustic grating structure with a PT structure, and for the first time considers the phase gradient modulation effect under the combination of classical structure and quantum-like effects. It achieves different acoustic wave modulation capabilities while maintaining consistent geometric dimensions on both sides of the structure. Furthermore, the structure is permeable, allowing air or fluid to pass through, which is helpful for specific applications, such as noise control where airflow is required to ensure heat dissipation.

[0029] The inventive points of this application include: 1. A method for constructing a phase gradient using a parity-time (PT) structure combined with a grating groove. 2. Excellent reflection performance even with a wide range of incident angles. 3. Different diffraction effects are generated on the upper and lower surfaces of the structure due to the introduction of the PT structure. 4. The design is applicable not only to sound waves but also to light waves. 5. When sound waves are incident on the upper surface, they can be reflected back along the original path; when incident on the lower surface, sound waves of half energy are reflected back along the original path, while the other half of the sound wave energy is mirror-reflected. 6. The structure is not limited to a single-layer structure but is also applicable to multi-layer structures composed of this type of structure.

[0030] This application provides a novel multifunctional acoustic double-sided mirror device, comprising a groove structure (1) and a parity-time (PT) structure (2). The upper and lower surfaces have different reflection phase gradient modulations. Due to the different phase gradients, the upper and lower surfaces of the structure exhibit different modulation performances for sound waves, i.e., a multifunctional acoustic double-sided mirror device. The upper surface has a phase gradient (8), while the lower surface has no phase gradient modulation (9). When a sound wave is incident on the upper surface (3), it will be completely reflected back along the original path due to the phase gradient factor (4). However, when a sound wave is incident on the lower surface (6), half of the sound wave energy is reflected back along the original path (7), and the other half of the sound wave energy undergoes specular reflection (5).

[0031] Parity-time structure is a structure with periodic loss modulation. Under certain structural conditions, a parity-time structure can achieve the effect of reflection on one side and no reflection on the other side. The refractive index distribution typically satisfies the following conditions: n(x) represents the refractive index at different spatial locations, n0 represents the refractive index of the background medium, n' represents the structure-modulated refractive index, and q = 2π / L, where L is the structure length, x is the spatial location, and i represents the imaginary part. These are the modulation parameters.

[0032] like Figure 2 The diagram illustrates the influence of structural parameters on the parity-time structure. It shows (a) the evolution of the modulation ratio, (b) the phase and (c) the variation of the reflection coefficient. The variation of amplitude and phase with n' is regulated by (d).

[0033] The working principle of this application is as follows: the diffracted wave incident on the upper surface follows the formula Where k0 is the sound wave vector in the air, It is the phase gradient. is the reciprocal lattice vector, p is the minimum cyclic period of the structure, and n is the diffraction order. and These are the angle of incidence and the angle of reflection, respectively. The diffracted wave incident on the lower surface follows the formula... Therefore, the structure exhibits different modulation properties on both sides, i.e., a two-sided mirror effect.

[0034] The groove structure (1) and the parity-time (PT) structure (2) are alternately connected to form the multifunctional acoustic double-sided mirror structure designed in this application. When placed in the required application scenario, it can modulate the wave field on both sides of the structure in different ways. The modulation performance is mainly due to the asymmetric reflection effect of the PT structure (2), that is, one end has reflection and the other end does not reflect. Therefore, after being alternately combined with the groove structure (1), the upper and lower surfaces have different phase gradients, that is, the upper surface has a phase gradient (8) and the lower surface does not have a phase gradient (9).

[0035] Compared to existing structures, this application provides a device design scheme with different modulation functions on both sides of the mirror structure. This design scheme can be applied not only to the acoustic wave field, but also to the optical wave system, solving the problem that existing schemes cannot achieve different wave field modulation functions when the structures on both sides are the same.

[0036] The multifunctional acoustic two-way mirror of this application, such as Figure 1 As shown, the double-sided mirror is composed of alternating combinations of air groove structures and PT structures. During use, placing this double-sided mirror in the desired application scenario allows for efficient, multi-dimensional modulation of sound waves. Different surfaces require different sound wave modulation methods, thus the orientation of the acoustic double-sided mirror can be adjusted as needed. The overall structure is stable and can be freely moved and adjusted. The sound wave reflection angle can also be controlled by rotating the double-sided mirror. Taking noise reduction as an example: the structure's airflow allows it to enclose noise sources, isolating noise interference. Furthermore, the airflow effectively dissipates heat, making it highly effective in noise isolation scenarios with heat sources.

[0037] Taking medical lenses as an example: For ultrasound imaging, the structure is placed on the surface of human tissue. When illuminated by sound waves, the structure can effectively reflect the signal back to the tissue. With the help of algorithms, an image of the human tissue can be reconstructed. Taking communications as an example: This structure has excellent negative reflection performance and can be placed on satellites or underwater ships. When a sound wave signal is incident, the highly efficient reflected signal returns along the original path and is detected, which can be used for military positioning and other functions.

[0038] like Figure 3 The diagram shows the evolution of the efficiency of different diffraction beams with respect to n' when surface acoustic waves are incident on this novel multifunctional acoustic double-sided mirror. Figure 4 The diagram shows the evolution of the efficiency of different diffraction beams with respect to n' when surface acoustic waves are incident on this novel multifunctional acoustic double-sided mirror. Figure 5 The diagram shown is a schematic of the multifunctional acoustic double-sided mirror structure of this application. When incident on the upper and lower surfaces, the energy intensity ratio of the two sound waves, B-4 and B-2, can reach a maximum asymmetry factor of 9.

[0039] The acoustic double-sided mirror of this application has a maximum reflected wave efficiency of 74.5% when incident on the upper surface (5). When incident on the lower surface, the negative reflection efficiency (7) can reach up to 25.6%, while the specular reflection efficiency (5) can reach up to 26%. The efficiency will fluctuate within a certain range for different incident angles, with a fluctuation of about 10%.

[0040] It should be noted that:

[0041] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0042] Similarly, it should be understood that, in order to simplify this application and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of this application, various features of this application are sometimes grouped together into a single embodiment, figure, or description thereof. However, this method of disclosure should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0043] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0044] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0045] It should be noted that the above embodiments are illustrative of this application and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. This application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several systems, several of these systems may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0046] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this application, and these should all be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A multifunctional acoustic double-sided mirror, characterized in that, include: Multiple groove structures and multiple parity time structures; The groove structure and the parity time structure are connected in series, and in the series structure, the groove structure and the parity time structure are distributed in a staggered manner. Each of the groove structures has two grooves, one above the other, and the two grooves together with the parity-time structure form the upper and lower surfaces of the double-sided mirror; The diffracted wave incident on the upper surface follows the formula ,in The sound wave vector in the air. It is the phase gradient. It is the reciprocal lattice vector, and p is the minimum cycle period of the structure; n is the diffraction order. and Let these be the incident angle and the reflection angle, respectively. For a diffracted wave incident on the lower surface, the following formula applies. .

2. The multifunctional acoustic double-sided mirror according to claim 1, characterized in that, The upper and lower surfaces have different reflection phase gradient modulations, and the upper and lower surfaces of the double-sided mirror have different modulation properties for sound waves.

3. The multifunctional acoustic double-sided mirror according to claim 2, characterized in that, The upper surface has a phase gradient, while the lower surface has no phase gradient modulation.

4. The multifunctional acoustic double-sided mirror according to claim 3, characterized in that, When a sound wave is incident on the upper surface, it is completely reflected back along its original path due to the phase gradient factor. When a sound wave is incident on the lower surface, half of the sound wave energy is reflected back along its original path, while the other half of the sound wave energy undergoes specular reflection.

5. The multifunctional acoustic double-sided mirror according to claim 1, characterized in that, The refractive index distribution of the parity-time structure satisfies , The refractive index at different locations in space. Indicates the refractive index of the background medium. Indicates the structurally modulated refractive index. =2π / L, where L is the structural length. It is spatial location. Indicates the imaginary part. These are the modulation parameters.

6. An application of the multifunctional acoustic double-sided mirror according to any one of claims 1-5 in the field of sound waves or optical systems.

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