A method for controlling the phase of light transmission in the local atmosphere using sound waves

Abstract

The present invention discloses a method for controlling the phase of light transmission in a local atmosphere using sound waves. The light waves are two different types of light waves: a plane light wave and a vortex beam, with a wavelength of λ=1550nm. The method is specifically implemented according to the following steps: Step 1: Analyze the disturbance of the refractive index of the atmosphere by the sound fields formed by different types of sound sources; Step 2: Obtain the refractive index distribution of the inhomogeneous atmosphere due to different sound wave parameters; Step 3: Obtain the optical path and phase changes of the plane light wave after the sound field disturbs the atmosphere; Step 4: Obtain the phases of the vortex beam at different heights after the sound field disturbance; Step 5: Achieve the control of the phase of light wave transmission in the atmosphere using sound waves. Obtaining the optical path and phase changes of the plane light wave after the sound field disturbs the atmosphere changes the previous idea of ​​passively avoiding the influence of the atmospheric channel on light transmission. Instead, it proposes actively controlling the atmospheric medium by changing the sound wave parameters, thereby controlling the phase of light transmission.

Description

Technical Field

[0001] The present invention relates to the field of optical transmission technology, and in particular to a method for regulating the optical transmission phase in a local atmosphere using sound waves. Background Art

[0002] Light is a crucial means of information transmission and acquisition. Research on the theory and application of light wave propagation in the atmosphere holds significant academic value and widespread application in national defense, military aerospace, and civilian fields. Due to the fluidity of the atmosphere, physical quantities such as pressure and temperature vary with spatial coordinates. These changes in pressure and temperature cause the atmospheric refractive index to fluctuate to some extent. Although these fluctuations are relatively small, they can still affect light transmission.

[0003] As carriers of information, sound waves and light waves play an extremely important role in the field of communications. When sound waves and light waves propagate in the same medium, the sound waves can change the density distribution of the medium, and then change the refractive index distribution of the medium, thereby affecting the optical properties of the medium and changing the transmission characteristics of the light waves. Therefore, for atmospheric media that can simultaneously transmit sound and light, sound waves can be used to regulate the transmission characteristics of light waves, thereby achieving the purpose of improving communication quality. In previous studies on the interaction between sound waves and light waves, ultrasonic sound fields were mostly used. However, because ultrasonic waves are extremely easy to lose in the atmosphere, the application scenarios are basically underwater environments. Therefore, in order to meet the needs of practical applications, it is very necessary to study the interaction between sound and light in the atmospheric environment.

[0004] Therefore, we use sound waves to disturb the local atmospheric environment, explore the mechanism of sound wave excitation to control the local atmosphere, and through the coupling of sound and light, study the changing laws and transmission characteristics of optical physical properties in the atmospheric environment under the action of sound waves, which is very helpful for effectively optimizing and improving the optical transmission performance on the ground-to-air link. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for regulating the phase of local atmospheric light transmission based on the acousto-optic effect. According to the quantitative relationship satisfied by the refractive index and density of the fluid, the relationship between the refractive index and the sound pressure of the medium during acoustic wave disturbance is obtained, thereby achieving the effect of controlling the acoustic wave parameters to affect the atmospheric refractive index, and then regulating the light transmission phase.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for controlling the phase of light transmission in a local atmosphere using acoustic waves, wherein the light waves are two different light waves: a plane light wave and a vortex beam, with a wavelength of λ = 1550nm, and the method is specifically implemented according to the following steps:

[0007] Step 1: Analyze the disturbance of the refractive index of the atmosphere caused by the sound fields generated by different types of sound sources;

[0008] Step 2: Extend step 1 to the real inhomogeneous atmosphere, change the acoustic wave parameters, and obtain the refractive index distribution of the inhomogeneous atmosphere with different acoustic wave parameters;

[0009] Step 3: Based on step 2, a model of the plane light wave passing through the atmosphere disturbed by the plane acoustic field is established to obtain the optical path and phase change of the plane light wave after the acoustic field disturbs the atmosphere;

[0010] Step 4: Establish an atmospheric model for a vortex beam with a beam diameter much smaller than that of the local environment passing through a plane acoustic field disturbance, and obtain the vortex beam phase at different heights after the acoustic field disturbance;

[0011] Step 5: After steps 3 and 4, analyze and discuss in detail the impact of acoustic wave disturbance on the phase transmission characteristics of light waves, summarize the changing rules, and thus achieve the purpose of using acoustic waves to regulate the transmission phase of light waves in the atmosphere.

[0012] Preferably, the step 1 is specifically implemented according to the following steps:

[0013] Step 1.1: Based on the quantitative relationship between the refractive index and density of the fluid, the relationship between the refractive index and the sound pressure of the medium during acoustic disturbance is obtained as follows:

[0014]

[0015] In formula (1), n0 is the refractive index of the medium itself, p0 is the pressure under static conditions, p is the sound pressure, and γ is the specific heat ratio;

[0016] Step 1.2: Based on the sound pressure formula of different sound sources, the disturbance of the sound field formed by different sound waves on the atmospheric refractive index is obtained from equation (1).

[0017] Preferably, step 2 is specifically implemented according to the following steps:

[0018] Step 2.1: In step 1, the refractive index of the medium after the plane wave source disturbs it shows a regular layer-uniform periodic distribution, which is similar to the case of an inhomogeneous atmosphere. Therefore, when discussing the real inhomogeneous atmosphere, a plane wave source is selected for further analysis.

[0019] Step 2.2: The atmospheric refractive index N0 of an inhomogeneous atmosphere where the atmospheric refractive index varies with altitude is:

[0020]

[0021]

[0022] N in formula (2) sis the atmospheric refractive index of the specified standard atmosphere, is the optical wavelength; in formula (3), n0 is the atmospheric refractive index, P h is the atmospheric pressure, p0 is the atmospheric pressure near the surface, x is the height, H = RT / gμ is the scale height, where μ is the atmospheric molar mass, R is the universal atmospheric constant, g is the acceleration due to gravity, and T is the absolute temperature;

[0023] Step 2.3: Substitute n0 in equation (3) into equation (1) in step 1 to obtain the refractive index n of the acoustically disturbed inhomogeneous atmospheric medium. f Formula (4) for (x, t) is:

[0024] In formula (4), p A is the sound pressure, k is the wave number, n0 is the atmospheric refractive index, Δn f is the change of the inhomogeneous atmospheric refractive index caused by the sound field, x is the height, t is the time, and ω is the angular frequency of the sound wave;

[0025]

[0026] Step 2.4: Obtain the variation of the refractive index of the non-uniform atmospheric medium with height and distance caused by the acoustic wave disturbance through step 2.3. Change the acoustic wave parameters to obtain the variation of the refractive index of the non-uniform atmosphere with height under different acoustic wave parameters.

[0027] Preferably, step 3 is specifically implemented according to the following steps:

[0028] Step 3.1: Assume that the incident plane light wave has a wavelength of λ = 1550 nm and enters the acoustic field along the positive z-axis, with a propagation direction perpendicular to the direction of the acoustic wave. Build a model for the plane light wave passing through an atmospheric medium disturbed by a plane acoustic field.

[0029] Step 3.2: The optical wavefront phase change Δθ caused by the acoustic field obtained in step 3.1 is:

[0030] Δθ=k·ΔL=k∫Δn(x,t)dz (5);

[0031] In formula (5), ΔL is the change in optical path length caused by the acoustic field, Δn is the change in refractive index caused by the acoustic field, and k is the wave number;

[0032] Step 3.3: The optical path L can be expressed as:

[0033] L = ∫ c ndz=∫ c (n0+Δn)dz (6);

[0034] In formula (6), n is the refractive index of the atmosphere after the sound wave disturbance, n0 is the refractive index of the medium itself, and c is the path of the light wave;

[0035] Preferably, step 4 is specifically implemented according to the following steps:

[0036] Step 4.1: Assume that the incident vortex beam has a wavelength of λ = 1550 nm and enters the acoustic field along the positive z-axis, with a propagation direction perpendicular to the direction of the acoustic wave. At the same time, it enters the atmospheric medium disturbed by the acoustic field from different heights. The vortex beam passes through the atmospheric medium model disturbed by the plane acoustic field.

[0037] Step 4.2: The field distribution of a Laguerre-Gaussian beam propagating in a medium can be expressed as:

[0038]

[0039] In formula (7), n is the refractive index of the medium, is the Laguerre polynomial, p is the order, l is the topological charge, and θ is the azimuth angle of the Laguerre-Gaussian beam; is the waist radius of the Laguerre-Gaussian beam at z, where w0 is the waist radius, is the Ruili distance, r is the polar diameter, and i is the imaginary unit;

[0040] Step 4.3: Substitute the refractive index calculated by equation (4) in step 2 into equation (7) to calculate the effect of the atmospheric medium disturbed by the plane acoustic field on the phase transmission characteristics of the vortex beam.

[0041] Preferably, step 5 is specifically implemented according to the following steps:

[0042] Step 5.1: Based on step 3, calculate the phase change and optical path of the plane light wave after passing through the acoustically perturbed inhomogeneous atmosphere. Because the refractive index of the inhomogeneous atmosphere varies with altitude, the phase change is zero when the plane light wave is not passing through the acoustic field. When passing through the acoustically perturbed inhomogeneous atmosphere, the optical path changes from a vertical plane to an inclined plane. After the acoustic field is added, the phase change of the optical path changes periodically with the variation of the acoustic wave. The overall optical path remains the same as when the acoustic field is not added, i.e., an inclined plane. However, due to the acoustic perturbation, the optical path fluctuates, demonstrating that acoustic waves can regulate the phase of plane light waves.

[0043] Step 5.2: Based on step 4, calculate the phase change of the Laguerre-Gaussian beam when it enters an inhomogeneous atmospheric medium disturbed by a plane acoustic field. When there is no acoustic field disturbance, the phase of the inhomogeneous atmospheric medium will also change with altitude, because the refractive index of each layer of the inhomogeneous atmospheric medium itself changes with altitude. After adding acoustic waves to the inhomogeneous atmospheric medium, the phase of the Laguerre-Gaussian beam at different altitudes also rotates compared to the phase without the addition of acoustic waves, proving that acoustic waves can regulate the phase of the vortex beam.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] Instead of passively avoiding the influence of atmospheric channels on optical transmission in previous transmission, it is proposed to actively control the atmospheric medium by changing the parameters of acoustic waves, thereby regulating the phase of optical transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 3D diagrams of the disturbance of the atmospheric refractive index by the sound field generated by different sound sources according to the embodiment of the present invention, (a) plane wave sound source, (b) spherical wave sound source, (c) cylindrical wave sound source;

[0047] Figure 2 2D diagrams of the disturbance of the atmospheric refractive index by the sound field generated by different sound sources according to the embodiment of the present invention, (a) plane wave sound source, (b) spherical wave sound source, (c) cylindrical wave sound source;

[0048] Figure 3 The embodiment of the present invention is a case where the refractive index of a non-uniform atmospheric medium undergoes acoustic disturbances and changes with height and distance;

[0049] Figure 4 is the variation of the non-uniform atmospheric refractive index with altitude under different sound wave parameters in the embodiment of the present invention (a) different sound wave frequencies, (b) different sound pressures;

[0050] Figure 5 This is a model of a plane light wave passing through an atmospheric medium disturbed by a plane sound field according to an embodiment of the present invention;

[0051] Figure 6 It is an atmospheric medium model of a vortex beam passing through a plane acoustic field disturbance according to an embodiment of the present invention;

[0052] Figure 7 : is the phase change of a plane light wave in an embodiment of the present invention, (a) before entering the acoustic field (z = 0 m, pa = 10 Pa), (b) after passing through the acoustic field (z = 20 m, pa = 10 Pa);

[0053] Figure 8 2. Path length changes of plane light waves according to an embodiment of the present invention: (a) in a soundless field (z = 20 m, pa = 0 Pa), and (b) in a sound field (z = 20 m, pa = 10 Pa).

[0054] Figure 9 1. Phase change of the vortex beam after adding sound waves into the inhomogeneous atmosphere medium of the embodiment of the present invention, (a) entering the inhomogeneous atmosphere without sound field, (b) entering the inhomogeneous atmosphere with plane sound field disturbance. DETAILED DESCRIPTION

[0055] The following will clearly and completely describe the technical solutions of the present invention in the embodiments of the present invention in conjunction with the drawings of the present invention in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0056] See also Figure 1-9 The present invention provides a technical solution: a method for controlling the phase of light transmission in a local atmosphere using acoustic waves. The light waves are two different light waves: a plane light wave and a vortex beam. The wavelength λ is 1550nm. The method is implemented in the following steps:

[0057] Step 1: Analyze the disturbance of the refractive index of the atmosphere caused by the sound fields generated by different types of sound sources. This is done by following the steps below:

[0058] Step 1.1: Based on the quantitative relationship between the refractive index and density of the fluid, the relationship between the refractive index and the sound pressure of the medium during acoustic disturbance is obtained as follows:

[0059]

[0060] In formula (1), n0 is the refractive index of the medium itself, p0 is the pressure under static conditions, p is the sound pressure, and γ is the specific heat ratio;

[0061] Step 1.2: According to the sound pressure formula of different sound sources, the disturbance of the sound field formed by different sound waves on the atmospheric refractive index is obtained from formula (1), such as Figure 1 and Figure 2 shown.

[0062] Step 2: Extend step 1 to the real inhomogeneous atmosphere, change the acoustic wave parameters, and obtain the refractive index distribution of the inhomogeneous atmosphere with different acoustic wave parameters; specifically, follow the steps below:

[0063] Step 2.1: In step 1, the refractive index of the medium after the plane wave source disturbs it shows a regular layer-uniform periodic distribution, which is similar to the case of an inhomogeneous atmosphere. Therefore, when discussing the real inhomogeneous atmosphere, a plane wave source is selected for further analysis.

[0064] Step 2.2: The atmospheric refractive index N0 of an inhomogeneous atmosphere where the atmospheric refractive index varies with altitude is:

[0065]

[0066]

[0067] N in formula (2) sis the atmospheric refractive index of the specified standard atmosphere, λ is the optical wavelength; in formula (3), n0 is the atmospheric refractive index, P h is the atmospheric pressure, p0 is the atmospheric pressure near the surface, x is the height, H = RT / gμ is the elevation, where μ is the atmospheric molar mass, R is the universal atmospheric constant, g is the acceleration due to gravity, and T is the absolute temperature;

[0068] Step 2.3: Substitute n0 in equation (3) into equation (1) in step 1 to obtain the refractive index n of the acoustically disturbed inhomogeneous atmospheric medium. f Formula (4) for (x, t) is:

[0069]

[0070] In formula (4), pA is the sound pressure, k is the wave number, n0 is the atmospheric refractive index, and Δn f is the change of the inhomogeneous atmospheric refractive index caused by the sound field, x is the height, t is the time, and ω is the angular frequency of the sound wave; Figure 3 As shown;

[0071] Step 2.4: If Figure 4 As shown, through step 2.3, the variation of the refractive index of the non-uniform atmospheric medium with height and distance caused by the acoustic wave disturbance is obtained. By changing the acoustic wave parameters, the variation of the refractive index of the non-uniform atmosphere with height under different acoustic wave parameters is obtained.

[0072] Step 3: Based on step 2, establish an atmospheric model of a plane light wave passing through a plane acoustic field disturbance, and obtain the optical path and phase change of the plane light wave after the acoustic field disturbs the atmosphere; specifically, implement the model in the following steps:

[0073] Step 3.1: Assume that the incident plane light wave has a wavelength of λ = 1550nm and enters the sound field along the positive direction of the z-axis. The propagation direction is perpendicular to the direction of the sound wave. Figure 5 A model of a plane light wave passing through an atmospheric medium disturbed by a plane acoustic field;

[0074] Step 3.2: The optical wavefront phase change Δθ caused by the acoustic field obtained in step 3.1 is:

[0075] Δθ=k·ΔL=k∫Δn(x,t)dz (5);

[0076] In formula (5), ΔL is the change in optical path length caused by the acoustic field, Δn is the change in refractive index caused by the acoustic field, and k is the wave number;

[0077] Step 3.3: The optical path L can be expressed as:

[0078] L = ∫ c ndz=∫ c (n0+Δn)dz (6);

[0079] In formula (6), n is the refractive index of the atmosphere after the sound wave disturbance, n0 is the refractive index of the medium itself, and c is the path of the light wave.

[0080] Step 4: Establish an atmospheric model for a vortex beam with a beam diameter much smaller than that of the local environment passing through a plane acoustic field disturbance, and obtain the vortex beam phase at different heights after the acoustic field disturbance. This is specifically implemented in the following steps:

[0081] Step 4.1: Assume that the incident vortex beam has a wavelength of λ = 1550nm, enters the sound field along the positive direction of the z axis, and the propagation direction is perpendicular to the direction of the sound wave. At the same time, it enters the atmospheric medium disturbed by the sound field from different heights. Figure 6 The vortex beam shown passes through the atmospheric medium model of the plane acoustic field disturbance;

[0082] Step 4.2: The field distribution of a Laguerre-Gaussian beam propagating in a medium can be expressed as:

[0083]

[0084] In formula (7), n is the refractive index of the medium, is the Laguerre polynomial, p is the order, l is the topological charge, and θ is the azimuth angle of the Laguerre-Gaussian beam; is the waist radius of the Laguerre-Gaussian beam at z, where w0 is the waist radius, is the Ruili distance, r is the polar diameter, and i is the imaginary unit;

[0085] Step 4.3: Substitute the refractive index calculated by equation (4) in step 2 into equation (7) to calculate the effect of the atmospheric medium disturbed by the plane acoustic field on the phase transmission characteristics of the vortex beam.

[0086] Step 5: After steps 3 and 4, analyze and discuss in detail the impact of acoustic wave perturbations on the light wave phase transmission characteristics, summarize the changing rules, and thus achieve the control of the light wave phase transmission in the atmosphere by acoustic waves. Specific implementation steps are as follows:

[0087] Step 5.1: According to step 3, calculate the phase change and optical path of the plane light wave after passing through the inhomogeneous atmospheric medium disturbed by the acoustic wave, as follows: Figure 7 and Figure 8 As shown in the figure, since the refractive index of the inhomogeneous atmosphere changes with altitude, when the plane light wave does not pass through the sound field, its phase change is 0. When passing through the inhomogeneous atmospheric medium without a sound field, the optical path changes from a vertical plane to an inclined plane. After the sound field is added, the phase change of the optical path will produce periodic changes according to the changing law of the sound wave. The overall optical path is the same as when the sound field is not added, that is, an inclined plane. However, due to the disturbance of the sound wave, the optical path will fluctuate, proving that sound waves can regulate the phase of plane light waves.

[0088] Step 5.2: According to step 4, calculate the phase change of the Laguerre-Gaussian beam entering the inhomogeneous atmospheric medium with plane acoustic field disturbance, as shown in Figure 9 As shown by Figure 9 (a) It can be seen that when there is no sound field disturbance, since the refractive index of each layer of the inhomogeneous atmospheric medium itself changes with the change of height, the phase of the inhomogeneous atmospheric medium will also change with the change of height, as shown by Figure 9 (a) and Figure 9 (b) By comparison, after adding sound waves to the inhomogeneous atmospheric medium, the phases of the Laguerre-Gaussian beams at different heights also rotate compared to the phases without the addition of sound waves, proving that sound waves can regulate the phase of the vortex beam.

[0089] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for controlling the phase of light transmission in a local atmosphere using acoustic waves, characterized in that: The light waves used are two different light waves: plane light waves and vortex beams, with a wavelength of λ = 1550nm. The specific implementation is as follows: Step 1: Analyze the disturbance of the refractive index of the atmosphere caused by the sound fields generated by different types of sound sources; Step 2: Extend step 1 to the real inhomogeneous atmosphere, change the acoustic wave parameters, and obtain the refractive index distribution of the inhomogeneous atmosphere with different acoustic wave parameters; Step 3: Based on step 2, a model of the plane light wave passing through the atmosphere disturbed by the plane acoustic field is established to obtain the optical path and phase change of the plane light wave after the acoustic field disturbs the atmosphere; Step 4: Establish an atmospheric model for a vortex beam with a beam diameter much smaller than that of the local environment passing through a plane acoustic field disturbance, and obtain the vortex beam phase at different heights after the acoustic field disturbance; Step 5: After steps 3 and 4, analyze and discuss in detail the effect of acoustic wave perturbations on the phase transmission characteristics of light waves, summarize the changing rules, and thus achieve the purpose of controlling the phase of light waves in the atmosphere by using acoustic waves. The step 5 is specifically implemented according to the following steps: Step 5.1: Based on step 3, calculate the phase change and optical path of the plane light wave after passing through the acoustically perturbed inhomogeneous atmosphere. Because the refractive index of the inhomogeneous atmosphere varies with altitude, the phase change is zero when the plane light wave is not passing through the acoustic field. When passing through the acoustically perturbed inhomogeneous atmosphere, the optical path changes from a vertical plane to an inclined plane. After the acoustic field is added, the phase change of the optical path changes periodically with the variation of the acoustic wave. The overall optical path remains the same as when the acoustic field is not added, i.e., an inclined plane. However, due to the acoustic perturbation, the optical path fluctuates, demonstrating that acoustic waves can regulate the phase of plane light waves. Step 5.2: Based on step 4, calculate the phase change of the Laguerre-Gaussian beam when it enters an inhomogeneous atmospheric medium disturbed by a plane acoustic field. When there is no acoustic field disturbance, the phase of the inhomogeneous atmospheric medium will also change with altitude, because the refractive index of each layer of the inhomogeneous atmospheric medium itself changes with altitude. After adding acoustic waves to the inhomogeneous atmospheric medium, the phase of the Laguerre-Gaussian beam at different altitudes also rotates compared to the phase without the addition of acoustic waves, proving that acoustic waves can regulate the phase of the vortex beam.

2. A method for controlling the phase of light transmission in a local atmosphere using acoustic waves according to claim 1, characterized in that: The step 1 is specifically implemented according to the following steps: Step 1.1: Based on the quantitative relationship between the refractive index and density of the fluid, the relationship between the refractive index and the sound pressure of the medium during acoustic disturbance is obtained as follows: In formula (1), n0 is the refractive index of the medium itself, p0 is the pressure under static conditions, and p A is the sound pressure, γ is the specific heat ratio; Step 1.2: Based on the sound pressure formula of different sound sources, the disturbance of the sound field formed by different sound waves on the atmospheric refractive index is obtained from equation (1).

3. A method for controlling the phase of light transmission in a local atmosphere using acoustic waves according to claim 1, characterized in that: The step 2 is specifically implemented according to the following steps: Step 2.1: In step 1, the refractive index of the medium after the plane wave source disturbs it shows a regular layer-uniform periodic distribution, which is similar to the case of an inhomogeneous atmosphere. Therefore, when discussing the real inhomogeneous atmosphere, a plane wave source is selected for further analysis. Step 2.2: The atmospheric refractive index N0 of an inhomogeneous atmosphere where the atmospheric refractive index varies with altitude is: N in formula (2) s is the atmospheric refractive index of the specified standard atmosphere, λ is the optical wavelength; in formula (3), n0 is the atmospheric refractive index, P h is the atmospheric pressure, p0 is the atmospheric pressure near the surface, x is the height, H = RT / gμ is the elevation, where μ is the atmospheric molar mass, R is the universal atmospheric constant, g is the acceleration of gravity, T is the absolute temperature, and n s is the refractive index of the specified standard atmosphere; Step 2.3: Substitute n0 in equation (3) into equation (1) in step 1 to obtain the refractive index n of the acoustically disturbed inhomogeneous atmospheric medium. f Formula (4) for (x, t) is: In formula (4), p A is the sound pressure, k is the wave number, n0 is the atmospheric refractive index, Δn f is the change of inhomogeneous atmospheric refractive index caused by the sound field, x is the height, t is the time, and ω is the angular frequency of the sound wave; Step 2.4: Obtain the variation of the refractive index of the non-uniform atmospheric medium with height and distance caused by the acoustic wave disturbance through step 2.

3. Change the acoustic wave parameters to obtain the variation of the refractive index of the non-uniform atmosphere with height under different acoustic wave parameters.

4. A method for controlling the phase of light transmission in a local atmosphere using acoustic waves according to claim 1, characterized in that: The step 3 is specifically implemented according to the following steps: Step 3.1: Assume that the incident plane light wave has a wavelength of λ = 1550 nm and enters the acoustic field along the positive z-axis, with a propagation direction perpendicular to the direction of the acoustic wave. Build a model for the plane light wave passing through an atmospheric medium disturbed by a plane acoustic field. Step 3.2: The optical wavefront phase change Δθ caused by the acoustic field obtained in step 3.1 is: Δθ=k·ΔL=k∫ c Δn(x,t)dz (5) In formula (5), ΔL is the change in optical path length caused by the acoustic field, Δn is the change in refractive index caused by the acoustic field, and k is the wave number; Step 3.3: The optical path L can be expressed as: L=∫ c ndz=∫ c (n0+Δn)dz (6) In formula (6), n is the refractive index of the atmosphere after the sound wave disturbance, n0 is the refractive index of the medium itself, and c is the path of the light wave.

5. A method for controlling the phase of light transmission in a local atmosphere using acoustic waves according to claim 1, characterized in that: The step 4 is specifically implemented according to the following steps: Step 4.1: Assume that the incident vortex beam has a wavelength of λ = 1550 nm and enters the acoustic field along the positive z-axis, with a propagation direction perpendicular to the direction of the acoustic wave. At the same time, it enters the atmospheric medium disturbed by the acoustic field from different heights. The vortex beam passes through the atmospheric medium model disturbed by the plane acoustic field. Step 4.2: The field distribution of a Laguerre-Gaussian beam propagating in a medium can be expressed as: In formula (7), n is the refractive index of the medium, is the Laguerre polynomial, p is the order, l is the topological charge, and θ is the azimuth angle of the Laguerre-Gaussian beam; is the waist radius of the Laguerre-Gaussian beam at z, where w0 is the waist radius, is the Ruili distance, r is the polar diameter, and i is the imaginary unit; Step 4.3: Substitute the refractive index calculated by equation (4) in step 2 into equation (7) to calculate the effect of the atmospheric medium disturbed by the plane acoustic field on the phase transmission characteristics of the vortex beam.

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