Sound pressure measurement method, sound pressure measurement apparatus, and computer-readable storage medium

Abstract

The present invention provides a sound pressure measurement method, a sound pressure measurement apparatus, and a computer-readable storage medium. The sound pressure measurement method comprises the following steps: emitting a detection beam along a preset path; when a sound wave to be measured is not loaded, acquiring an initial irradiation position of the detection beam and an initial illuminance of the initial irradiation position; when loading said sound wave, acquiring a deviation illuminance between a deflected irradiation position and the initial irradiation position after the detection beam passes through a sound field of said sound wave; and determining an irradiation position offset of the deflected irradiation position relative to the initial irradiation position and an illuminance deviation value of the deviation illuminance relative to the initial illuminance, and on the basis of the irradiation position offset and the illuminance deviation value, determining a sound pressure value of the sound field of said sound wave at each position on the preset path. The sound pressure measurement method, the sound pressure measurement apparatus, and the computer-readable storage medium provided in the present invention can improve the accuracy, measurement range, and spatial resolution of sound pressure measurement, thereby meeting the requirements of HIFU sound field sound pressure measurement.

Description

Sound pressure measurement method, sound pressure measurement device, and computer-readable storage medium TECHNICAL FIELD

[0001] The present application relates to the technical field of ultrasound, in particular to a sound pressure measurement method, a sound pressure measurement device, and a computer-readable storage medium. BACKGROUND

[0002] High Intensity Focused Ultrasound (HIFU) can transmit ultrasound waves from outside the body to the body, and realize sound energy convergence in a specific target area or lesion in the body, so as to realize local thermal damage or mechanical damage of the specific target area or lesion by high-energy sound waves, thereby realizing non-invasive and non-invasive treatment. The sound field parameters of HIFU are very important physical parameters for the effectiveness and safety of HIFU, and are crucial for optimizing and standardizing the application and development of HIFU.

[0003] However, in the prior art, the sound pressure measurement method has the problems of low measurement accuracy, low measurement range, and low spatial resolution, which cannot meet the measurement requirements of the HIFU sound field sound pressure. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the prior art, and provides a sound pressure measurement method, a sound pressure measurement device, and a computer-readable storage medium, which can improve the sound pressure measurement accuracy, the measurement range, and the spatial resolution, thereby meeting the measurement requirements of the HIFU sound field sound pressure.

[0005] To achieve the purpose of the present application, a sound pressure measurement method is provided, comprising the following steps:

[0006] emitting a detection light beam along a preset path;

[0007] When the to-be-measured sound wave is not loaded, obtaining an initial irradiation position of the detection light beam and an initial irradiance of the initial irradiation position;

[0008] When the to-be-measured sound wave is loaded, obtaining a deflection irradiation position of the detection light beam after penetrating the to-be-measured sound wave sound field and a deviation irradiance of the initial irradiation position;

[0009] determining an irradiation position offset of the deflection irradiation position relative to the initial irradiation position and an irradiance deviation value of the deviation irradiance relative to the initial irradiance, and determining a sound pressure value of each position of the to-be-measured sound wave sound field on the preset path according to the irradiation position offset and the irradiance deviation value.

[0010] Optionally, the acquiring the deviation illuminance of the deflected irradiation position after the detection light beam penetrates the sound field of the to-be-tested sound wave and the initial irradiation position specifically comprises:

[0011] acquiring the deviation illuminance of the deflected irradiation position after the detection light beam penetrates the sound field of the to-be-tested sound wave and the initial irradiation position at a plurality of to-be-tested time instants within one period of the to-be-tested sound wave;

[0012] the determining the irradiation position offset of the deflected irradiation position relative to the initial irradiation position and the illuminance deviation value of the deviation illuminance relative to the initial illuminance, and the determining the sound pressure value of each position on the preset path of the sound field of the to-be-tested sound wave according to the irradiation position offset and the illuminance deviation value specifically comprises:

[0013] determining a plurality of irradiation position offsets of a plurality of deflected irradiation positions relative to the initial irradiation position and a plurality of illuminance deviation values of a plurality of deviation illuminances relative to the initial illuminance, and determining the sound pressure value of each position on the preset path of the sound field of the to-be-tested sound wave at a plurality of to-be-tested time instants according to a plurality of irradiation position offsets and a plurality of illuminance deviation values corresponding to the plurality of to-be-tested time instants one by one.

[0014] Optionally, the determining the sound pressure value of each position on the preset path of the sound field of the to-be-tested sound wave at a plurality of to-be-tested time instants according to a plurality of irradiation position offsets and a plurality of illuminance deviation values corresponding to the plurality of to-be-tested time instants one by one specifically comprises:

[0015] determining the measured refractive index of each position on the preset path of the to-be-tested sound wave at a plurality of to-be-tested time instants according to a preset refractive index gradient integral relationship, and determining the sound pressure value according to the measured refractive index, the refractive index gradient integral relationship being:

[0016] wherein a and b are correction coefficients relative to a standard sound wave of the to-be-tested sound wave, x is a coordinate in a first direction, y is a coordinate in a second direction, z is a coordinate in a third direction, the first direction and the second direction are perpendicular and located on a first plane perpendicular to a projection plane of the sound field of the to-be-tested sound wave, the third direction is perpendicular to the first plane, t is the to-be-tested time instant, ΔI is the illuminance deviation value, v is the irradiation position offset, L is the length of the sound field of the to-be-tested sound wave in the third direction, and ∇n is the refractive index gradient.

[0017] Optionally, the determining the sound pressure value according to the measured refractive index specifically comprises:

[0018] determining the sound pressure value according to the measured refractive index and a preset first relationship, the first relationship being:

[0019] wherein n is the measured refractive index, n0 is the refractive index of the medium loaded by the to-be-measured acoustic wave when the medium is not loaded by the to-be-measured acoustic wave, is the photoelastic coefficient of the medium loaded by the to-be-measured acoustic wave, and p is the acoustic pressure value.

[0020] Optionally, the detection light beam is a Gaussian light beam.

[0021] Optionally, the initial irradiation position and the deflected irradiation position of the Gaussian light beam are both the irradiance peak positions of the Gaussian light beam.

[0022] Optionally, the acoustic pressure measurement method further comprises the steps of:

[0023] setting a three-dimensional matrix for the to-be-measured acoustic wave field and determining the acoustic pressure value of each element of the three-dimensional matrix.

[0024] Optionally, the step of setting a three-dimensional matrix for the to-be-measured acoustic wave field and determining the acoustic pressure value of each element of the three-dimensional matrix specifically comprises:

[0025] emitting the detection light beam along multiple preset paths in the three-dimensional direction of the three-dimensional matrix;

[0026] determining the acoustic pressure value of each position corresponding to each element of the three-dimensional matrix on the multiple preset paths.

[0027] Optionally, the step of emitting the detection light beam along multiple preset paths in the three-dimensional direction of the three-dimensional matrix specifically comprises:

[0028] setting a first plane perpendicular to the projection plane of the to-be-measured acoustic wave field;

[0029] making the to-be-measured acoustic wave complete one revolution by multiple self-rotations;

[0030] emitting the detection light beam along a preset path perpendicular to the first plane between adjacent two self-rotations of the to-be-measured acoustic wave and after one revolution, and making the detection light beam scan the first plane.

[0031] Optionally, the step of emitting the detection light beam along a preset path perpendicular to the first plane and making the detection light beam scan the first plane specifically comprises:

[0032] setting multiple path groups, each of the path groups comprising multiple preset paths, the multiple preset paths of the same path group being distributed at intervals in a first direction of the first plane parallel to the projection plane of the to-be-measured acoustic wave field, and the multiple path groups being distributed at intervals in a second direction of the first plane perpendicular to the first direction.

[0033] sequentially emit the detection light beams according to the order of the path groups.

[0034] The present application also provides a sound pressure measuring device for performing the sound pressure measuring method provided by the present application, the sound pressure measuring device comprising a light source, an acquisition component and a controller, the light source being configured to emit the detection light beams, the acquisition component being configured to acquire the detection light beams, and the controller being signal connected with the light source and the acquisition component respectively and configured to control the start and stop of the light source and the acquisition of the detection light beams by the acquisition component.

[0035] Optionally, the sound pressure measuring device further comprises a first moving component, a second moving component and a rotating component, the first moving component being connected with the light source and configured to drive the light source to move in a first direction and a second direction, the first direction and the second direction being perpendicular and located on a first plane perpendicular to a projection plane of the sound field of the sound wave to be measured, the second moving component being connected with the acquisition component and configured to move synchronously with the first moving component and drive the acquisition component to move synchronously with the light source, and the rotating component being connected with a sound source configured to provide the sound wave to be measured and configured to drive the sound source to rotate.

[0036] Optionally, the light source has a variation rate of output power less than or equal to 1%.

[0037] The present application also provides a computer readable storage medium, the computer readable storage medium storing a computer program, the computer program being capable of realizing the sound pressure measuring method provided by the present application when executed by a processing module.

[0038] The present application has the following advantages:

[0039] The sound pressure measurement method provided by the application can determine the sound pressure value of each position of the sound field of the to-be-measured sound wave on the preset path according to the irradiation position offset and the irradiance deviation value, because the irradiance change of the detection light beam is more sensitive to the sound field pressure of the to-be-measured sound wave compared with the irradiation position of the detection light beam, that is, when the sound field pressure of the to-be-measured sound wave changes slightly, the irradiance of the detection light beam can change greatly, and the irradiance change of the detection light beam can be detected more easily and more accurately, therefore, the sound pressure measurement accuracy, measurement range and spatial resolution can be improved by determining the sound pressure value of each position of the sound field of the to-be-measured sound wave on the preset path according to the irradiation position offset and the irradiance deviation value, thereby meeting the measurement requirement of the HIFU sound field pressure.

[0040] The sound pressure measurement device provided by the application can improve the sound pressure measurement accuracy, measurement range and spatial resolution by executing the sound pressure measurement method provided by the application, thereby meeting the measurement requirement of the HIFU sound field pressure.

[0041] The computer readable storage medium provided by the application stores the computer program which can implement the sound pressure measurement method provided by the application when executed by the processing module, thereby improving the sound pressure measurement accuracy, measurement range and spatial resolution, and further meeting the measurement requirement of the HIFU sound field pressure. BRIEF DESCRIPTION OF DRAWINGS

[0042] Fig. 1 is a flow chart of the sound pressure measurement method provided by the embodiment of the application;

[0043] Fig. 2 is a structural schematic view of the sound pressure measurement device provided by the embodiment of the application;

[0044] Fig. 3 is a schematic view of the propagation direction of the detection light beam penetrating the sound field of the to-be-measured sound wave when the to-be-measured sound wave is not loaded and when the to-be-measured sound wave is loaded in the embodiment of the application;

[0045] Fig. 4 is a schematic view of the irradiation position and irradiance of the detection light beam penetrating the sound field of the to-be-measured sound wave when the to-be-measured sound wave is not loaded in the embodiment of the application;

[0046] Fig. 5 is a schematic view of the irradiation position and irradiance of the detection light beam penetrating the sound field of the to-be-measured sound wave when the to-be-measured sound wave is loaded in the embodiment of the application;

[0047] Explanation of reference signs: 1-light source; 2-acquisition component; 3-controller; 4-first moving component; 5-second moving component; 6-rotating component; 7-signal generator; 8-power amplifier; 9-computer; 10-sound source; 11-holding component; 12-light beam adjusting assembly; 121-focusing lens; 122-pinhole filter; 123-collimating lens. DETAILED DESCRIPTION

[0048] In order for those skilled in the art to better understand the technical solutions of the present application, first, the present application will introduce the related sound pressure measurement method and device used by the inventor of the present application for high intensity focused ultrasound.

[0049] The inventor of the present application has carried out sound pressure measurement experiments on high intensity focused ultrasound (High Intensity Focused Ultrasound, abbreviated as HIFU) using invasive hydrophones, including needle hydrophones and film hydrophones based on piezoelectric effect, and optical fiber hydrophones based on optical sensing. The inventor of the present application found that the hydrophone based on piezoelectric effect is easily affected by electromagnetic interference, resulting in a large deviation between the measured sound pressure value and the actual sound pressure value, and a low accuracy of sound pressure measurement. Moreover, the sensing interface of the hydrophone based on piezoelectric effect is rigid, and the medium loaded by the invasive sound wave will cause the early occurrence of medium cavitation effect, which is easy to cause damage to the sensing component, therefore, the hydrophone based on piezoelectric effect can usually only measure sound pressure with an amplitude less than ten megapascals, and cannot meet the measurement of the sound pressure of HIFU with an amplitude reaching tens of megapascals. In addition, the hydrophone based on piezoelectric effect can usually only measure the sound pressure of sound waves with a frequency of one megahertz to ten megahertz, and cannot meet the measurement of the sound pressure of HIFU with a frequency reaching tens of megahertz to hundreds of megahertz, resulting in a small range of sound pressure measurement. The inventor of the present application found that the optical fiber hydrophone based on optical sensing has a free end at the end of the optical fiber when measuring sound pressure, which is easy to swing under the influence of acoustic radiation force, resulting in a large deviation between the measured sound pressure value and the actual sound pressure value, and a low accuracy of sound pressure measurement. Moreover, the way of measuring sound pressure by the hydrophone, since the sensing component of the hydrophone needs to invade the medium loaded by the sound wave, the sensing component will cause interference to the sound field, and the measurement method of the hydrophone has a spatial averaging effect, resulting in a large deviation between the measured sound pressure value and the actual sound pressure value, and a low accuracy of sound pressure measurement.

[0050] The inventors of the present application also carried out an acoustic pressure determination experiment on HIFU by using a non-invasive optical measurement method, which includes a schlieren imaging method and a laser deflection method. The inventors of the present application found that the image obtained by the schlieren imaging method is the two-dimensional projection information of the sound field medium, and the diffracted light from different spaces in the direction of light beam propagation will superimpose and affect each other, which is difficult to accurately restore the sound pressure of the sound field, so the schlieren imaging method can only determine the sound pressure with an amplitude lower than one megapascal, and when the local sound pressure of the sound field is too high, the light beam will be severely deflected and form high-order diffraction, which is difficult to analyze the sound pressure with a higher amplitude from the two-dimensional projection light intensity distribution information, so for the sound pressure with a higher amplitude such as HIFU, the measured value of the schlieren imaging method deviates greatly from the actual value of the sound pressure, the accuracy of the sound pressure determination is low, and the sound pressure determination range is small. The inventors of the present application found that the spatial resolution of the laser deflection method for determining the sound pressure can only reach the order of 2 mm, the spatial resolution is low, and it is difficult to meet the determination requirements of the sound field sound pressure of high-frequency sound waves such as HIFU.

[0051] The sound pressure determination method, the sound pressure determination device and the computer readable storage medium provided by the present application will be described in detail below in combination with the drawings.

[0052] As shown in FIG. 1, the present application provides a sound pressure determination method, which comprises the following steps:

[0053] S1, emitting a detection light beam along a preset path;

[0054] S2, obtaining an initial irradiation position of the detection light beam and an initial irradiance of the initial irradiation position when no measured sound wave is loaded;

[0055] S3, obtaining a deflected irradiation position of the detection light beam after penetrating the sound field of the measured sound wave and a deviation irradiance of the initial irradiation position when the measured sound wave is loaded;

[0056] S4, determining an irradiation position offset of the deflected irradiation position relative to the initial irradiation position and an irradiance deviation value of the deviation irradiance relative to the initial irradiance, and determining the sound pressure value of each position of the sound field of the measured sound wave on the preset path according to the irradiation position offset and the irradiance deviation value.

[0057] The sound pressure measurement method provided by the embodiment of the present application can obtain the initial irradiation position of the detection light beam and the initial irradiance of the initial irradiation position when the to-be-measured sound wave is not loaded, and can obtain the deflected irradiation position of the detection light beam after penetrating the to-be-measured sound wave sound field and the deflection irradiance of the initial irradiation position when the to-be-measured sound wave is loaded, and can determine the irradiation position offset of the deflected irradiation position relative to the initial irradiation position and the irradiance deflection value of the deflection irradiance relative to the initial irradiance, and can determine the sound pressure value of each position of the to-be-measured sound wave sound field on the preset path according to the irradiation position offset and the irradiance deflection value. Since the irradiance change of the detection light beam is more sensitive to the sound field sound pressure of the to-be-measured sound wave compared with the irradiation position of the detection light beam, that is, when the sound field sound pressure of the to-be-measured sound wave changes slightly, the irradiance of the detection light beam can change greatly, and the irradiance change of the detection light beam can be detected more easily and more accurately, therefore, determining the sound pressure value of each position of the to-be-measured sound wave sound field on the preset path according to the irradiation position offset and the irradiance deflection value can improve the sound pressure measurement accuracy, measurement range and spatial resolution, thereby meeting the measurement requirement of the HIFU sound field sound pressure.

[0058] Specifically, in actual application, an auxiliary medium can be prepared for the to-be-measured sound wave to form a sound field of the to-be-measured sound wave, the auxiliary medium meets the requirement of being penetrated by the detection light beam, and the density of the auxiliary medium can change under the influence of the sound field sound pressure of the to-be-measured sound wave. After the auxiliary medium is prepared, the detection light beam can be emitted to the auxiliary medium along the preset path without loading the to-be-measured sound wave to the auxiliary medium. At this time, as shown in FIGS. 3 and 4, the propagation direction of the detection light beam will not be deflected in the process of penetrating the auxiliary medium, the position irradiated by the detection light beam after penetrating the auxiliary medium is the initial irradiation position, and the irradiance of the detection light beam at the initial position after penetrating the auxiliary medium is the initial irradiance. Then, the to-be-measured sound wave can be loaded to the auxiliary medium, and the detection light beam can continue to be emitted to the auxiliary medium along the preset path. At this time, as shown in FIGS. 3 and 5, the propagation direction of the detection light beam will be deflected due to the influence of the sound field sound pressure of the to-be-measured sound wave in the process of penetrating the auxiliary medium, the position irradiated by the detection light beam after penetrating the auxiliary medium is deflected relative to the initial irradiation position to be the deflected irradiation position, and since the position irradiated by the detection light beam after penetrating the auxiliary medium is deflected relative to the initial irradiation position, the irradiance of the detection light beam at the initial position after penetrating the auxiliary medium will be deflected relative to the initial irradiance to be the deflection irradiance.

[0059] Afterwards, the irradiation position offset of the deflected irradiation position relative to the initial irradiation position and the irradiance deviation value of the deflected irradiance relative to the initial irradiance can be determined, since the irradiation position offset and the irradiance deviation value are the results of the cumulative changes of the detection light beam in the process of penetrating the to-be-measured acoustic wave sound field, which are affected by the sound field pressure of the to-be-measured acoustic wave at each position on the preset path, that is, the detection light beam is changed due to the influence of the sound field pressure of the to-be-measured acoustic wave at each position on the preset path in the process of penetrating the to-be-measured acoustic wave sound field, and finally irradiates on the deflected irradiation position with the irradiation position offset relative to the initial irradiation position after penetrating the to-be-measured acoustic wave sound field, and the irradiance at the initial irradiation position is the deflected irradiance with the irradiance deviation value relative to the initial irradiance, therefore, the sound pressure value of the to-be-measured acoustic wave sound field at each position on the preset path can be determined according to the irradiation position offset and the irradiance deviation value.

[0060] Optionally, the auxiliary medium can be water.

[0061] Optionally, the to-be-measured acoustic wave can be a high intensity focused ultrasound (HIFU).

[0062] Optionally, the angle between the preset path and the projection plane of the to-be-measured acoustic wave sound field can be 0°. That is, the preset path can be parallel to the projection plane of the to-be-measured acoustic wave sound field.

[0063] Optionally, the detection light beam can be a laser.

[0064] In an embodiment of the present application, obtaining the deflected irradiation position and the deflected irradiance of the initial irradiation position after the detection light beam penetrates the to-be-measured acoustic wave sound field can specifically include:

[0065] Obtaining the deflected irradiation position and the deflected irradiance of the initial irradiation position after the detection light beam penetrates the to-be-measured acoustic wave sound field at a plurality of to-be-measured time points in a period of the to-be-measured acoustic wave;

[0066] Determining the irradiation position offset of the deflected irradiation position relative to the initial irradiation position and the irradiance deviation value of the deflected irradiance relative to the initial irradiance, and determining the sound pressure value of the to-be-measured acoustic wave sound field at each position on the preset path according to the irradiation position offset and the irradiance deviation value can specifically include:

[0067] Determining a plurality of irradiation position offsets of a plurality of deflected irradiation positions relative to the initial irradiation position and a plurality of irradiance deviation values of a plurality of deflected irradiances relative to the initial irradiance, and determining the sound pressure value of the to-be-measured acoustic wave sound field at each position on the preset path at a plurality of to-be-measured time points according to a plurality of irradiation position offsets and a plurality of irradiance deviation values corresponding to the plurality of to-be-measured time points one by one.

[0068] Such a design is due to the fact that the sound field pressure of the to-be-measured sound wave is periodically changed, and at different moments within a period of the to-be-measured sound wave, the sound pressure at the same position on the preset path can be different, so that at different moments within a period of the to-be-measured sound wave, the position irradiated by the detection beam after penetrating the auxiliary medium can be different, and the illumination at the initial irradiation position can be different. Therefore, by acquiring the deflection illumination deviation between the deflection irradiation position and the initial irradiation position of the detection beam after penetrating the sound field of the to-be-measured sound wave at multiple to-be-measured moments within a period of the to-be-measured sound wave, that is, acquiring multiple deflection irradiation positions corresponding to multiple to-be-measured moments and multiple illumination deviations corresponding to multiple to-be-measured moments within a period of the to-be-measured sound wave, and then determining multiple irradiation position offsets of the multiple deflection irradiation positions relative to the initial irradiation position and multiple illumination deviation values of the multiple illumination deviations relative to the initial illumination, that is, determining multiple irradiation position offsets corresponding to multiple deflection irradiation positions and multiple illumination deviation values corresponding to multiple illumination deviations, that is, determining multiple irradiation position offsets corresponding to multiple to-be-measured moments and multiple illumination deviation values corresponding to multiple to-be-measured moments, the sound pressure values of the sound field of the to-be-measured sound wave at each position on the preset path at multiple to-be-measured moments can be determined according to the multiple irradiation position offsets and the multiple illumination deviation values corresponding to the multiple to-be-measured moments, that is, the sound pressure values of the sound field of the to-be-measured sound wave at each position on the preset path at each to-be-measured moment can be determined.

[0069] In an embodiment of the present application, determining the sound pressure values of the sound field of the to-be-measured sound wave at each position on the preset path at multiple to-be-measured moments according to the multiple irradiation position offsets and the multiple illumination deviation values corresponding to the multiple to-be-measured moments can specifically include:

[0070] Determining the measured refractive index of the detection beam at each position on the preset path at multiple to-be-measured moments according to the preset refractive index gradient integral relationship, and determining the sound pressure values according to the measured refractive index, the refractive index gradient integral relationship is:

[0071] Wherein a and b are correction coefficients relative to a standard sound wave of the to-be-measured sound wave, x is a coordinate in a first direction (as shown by direction x in FIGS. 2-4), y is a coordinate in a second direction (as shown by direction y in FIGS. 2-4), z is a coordinate in a third direction (as shown by direction z in FIGS. 2 and 3), the first direction and the second direction are perpendicular and located on a first plane perpendicular to the projection plane of the sound field of the to-be-measured sound wave, the third direction is perpendicular to the first plane, t is a to-be-measured moment, ΔI is an illumination deviation value, v is an irradiation position offset, L is the length of the sound field of the to-be-measured sound wave in the third direction, is the refractive index gradient.

[0072] Specifically, the projection plane of the sound field of the to-be-detected sound wave is a plane in which the direction x and the direction z in FIGS. 2 and 3 are located, the first plane perpendicular to the projection plane of the sound field of the to-be-detected sound wave can be a plane in which the direction x and the direction y in FIGS. 2-4 are located, the to-be-detected light beam emitted along the preset path can irradiate on the first plane after penetrating the sound field of the to-be-detected sound wave, the irradiation position coordinate of the to-be-detected light beam on the first plane after penetrating the sound field of the to-be-detected sound wave at the to-be-detected moment is (x, y, t), taking the coordinate of the initial irradiation position as the origin (0, 0), v(x, y, t) represents the irradiation position offset on the first plane at the to-be-detected moment, ΔI(t) represents the irradiance deviation value of the initial irradiation position at the to-be-detected moment, represents the refractive index gradient at the to-be-detected moment, the third direction can be parallel to the preset path, the coordinate of a position on the preset path can be represented as (x, y, z), by determining the coordinate z of the third direction, the position on the preset path can be determined, and thus the measured refractive index of the detection light beam at each position on the preset path at multiple to-be-detected moments can be determined according to the preset refractive index gradient integral relationship. The correction coefficients a and b are correction coefficients of a standard sound wave relative to the to-be-detected sound wave. In actual application, the correction coefficients a and b can be different for sound waves with different powers, and thus the sound field sound pressure of the standard sound wave can be measured by means of the sound pressure measurement method provided in the embodiment of the present application to obtain a measurement value, and the measurement value is corrected according to the actual value of the actual sound field sound pressure of the standard sound wave (for example, a sound wave emitted by a standard transducer) to determine the correction coefficients a and b, so that the sound pressure measurement accuracy and the measurement range can be improved.

[0073] The design is because when the auxiliary medium is not loaded with the to-be-tested acoustic wave, the refractive index of the auxiliary medium at different positions to the detection beam is the same when the detection beam penetrates the auxiliary medium, so at this time, the propagation direction of the detection beam will not be deflected when the detection beam penetrates the auxiliary medium. When the auxiliary medium is loaded with the to-be-tested acoustic wave, the density of the auxiliary medium at different positions becomes different due to the influence of the sound field pressure of the to-be-tested acoustic wave, and the refractive index of the auxiliary medium at different positions to the detection beam is different due to the different densities of the auxiliary medium at different positions, that is, the refractive index of the auxiliary medium at different positions to the detection beam is different when the detection beam penetrates the auxiliary medium, so at this time, the propagation direction of the detection beam will be deflected due to the different refractive indexes of the auxiliary medium at different positions to the detection beam when the detection beam penetrates the auxiliary medium. Moreover, at different moments in a period of the to-be-tested acoustic wave, the sound pressure at the same position on the preset path may be different, so the refractive index of the auxiliary medium at the same position on the preset path to the detection beam at different moments in a period of the to-be-tested acoustic wave may be different, so at different moments in a period of the to-be-tested acoustic wave, the propagation direction of the detection beam may be different, the position irradiated by the detection beam after penetrating the auxiliary medium may be different, and the illumination at the initial irradiation position after the detection beam penetrates the auxiliary medium may be different.

[0074] Moreover, the irradiation position offset and the illumination deviation value are the results of the cumulative changes of the detection beam in the process of penetrating the sound field of the to-be-tested acoustic wave, that is, the results of the cumulative changes of the detection beam due to the influence of the refractive index of the auxiliary medium at each position on the preset path to the detection beam, so finally, after penetrating the sound field of the to-be-tested acoustic wave, the deflected irradiation position offset by the irradiation position offset relative to the initial irradiation position, and the deviation illumination offset by the illumination deviation value relative to the initial illumination at the initial irradiation position, so the measured refractive index of the detection beam at each position on the preset path at a plurality of to-be-tested moments can be determined according to the preset refractive index gradient integral relationship, and the sound pressure value can be determined according to the measured refractive index.

[0075] Optionally, ΔI(t)=(I0-I(t)) / I0, wherein I0 is the initial illumination, and I(t) is the deviation illumination at the to-be-tested moment.

[0076] In an embodiment of the present application, determining the sound pressure value according to the measured refractive index can specifically include:

[0077] determining the sound pressure value according to the measured refractive index and a preset first relationship, and the first relationship is:

[0078] wherein n is the measured refractive index, n0 is the refractive index of the medium loaded with the sound wave to be measured when the medium is not loaded with the sound wave to be measured, is the photoelastic coefficient of the medium loaded with the sound wave to be measured, and p is the sound pressure value.

[0079] Specifically, n(x, y, z) represents the measured refractive index at a position on the preset path, and p(x, y, z) represents the sound pressure value at a position on the preset path. In actual application, the refractive index gradient value at each position on the preset path can be determined according to the preset refractive index gradient integral, so that the measured refractive index n at each position on the preset path can be determined. Since the photoelastic coefficient and the refractive index n0 of the medium loaded with the sound wave to be measured when the medium is not loaded with the sound wave to be measured can be known, the sound pressure value p at each position on the preset path can be determined according to the first relationship.

[0080] As shown in FIGS. 4 and 5, in an embodiment of the present application, the detection light beam can be a Gaussian light beam.

[0081] As shown in FIGS. 4 and 5, in an embodiment of the present application, the initial irradiation position and the deflected irradiation position of the Gaussian light beam are both the irradiance peak position of the Gaussian light beam.

[0082] That is, in actual application, when the medium is not loaded with the sound wave to be measured, the position where the irradiance peak of the Gaussian light beam irradiation is located can be the initial irradiation position, and the irradiance peak of the Gaussian light beam irradiation can be the initial irradiance. When the medium is loaded with the sound wave to be measured, the propagation direction of the Gaussian light beam is deflected, the position where the irradiance peak of the Gaussian light beam irradiation is located changes, the position where the irradiance peak of the Gaussian light beam irradiation can no longer be located at the initial irradiation position, and the non-irradiance peak of the Gaussian light beam irradiation can be located at the initial irradiation position. At this time, the position where the irradiance peak of the Gaussian light beam irradiation is located can be used as the deflected irradiation position, and the non-irradiance peak of the Gaussian light beam at the initial irradiation position can be used as the deflection irradiance.

[0083] In an embodiment of the present application, the sound pressure measurement method can further include the steps of:

[0084] A three-dimensional matrix is set for the sound field of the sound wave to be measured, and the sound pressure value of each element of the three-dimensional matrix is determined.

[0085] The design is due to the fact that the sound field of the to-be-tested sound wave is distributed in a three-dimensional space, by setting a three-dimensional matrix for the sound field of the to-be-tested sound wave and determining the sound pressure value of each element of the three-dimensional matrix, the distribution of the sound field of the to-be-tested sound wave in the three-dimensional space in which the sound field is distributed can be determined, and the diffraction superposition problem caused by determining the sound pressure in a two-dimensional space can be avoided, thereby improving the sound pressure determination accuracy, determination range and spatial resolution, and further meeting the determination requirement of the sound pressure of the HIFU sound field.

[0086] In actual application, the three-dimensional matrix is set for the sound field of the to-be-tested sound wave, that is, the three-dimensional space in which the sound field of the to-be-tested sound wave is distributed is meshed, and the minimum mesh size that can be divided is the minimum determination precision, and the smaller the determination precision is, the higher the determination accuracy and spatial resolution are.

[0087] In an embodiment of the present application, setting a three-dimensional matrix for the sound field of the to-be-tested sound wave and determining the sound pressure value of each element of the three-dimensional matrix can specifically include:

[0088] emitting a detection light beam along a plurality of preset paths in the three-dimensional direction of the three-dimensional matrix;

[0089] determining the sound pressure value of each position corresponding to each element of the three-dimensional matrix on the plurality of preset paths.

[0090] In actual application, by emitting a detection light beam along a plurality of preset paths in the three-dimensional direction of the three-dimensional matrix, since the detection light beam emitted along one preset path can penetrate a plurality of elements in one dimension direction of the three-dimensional matrix, the sound pressure value of each position on one preset path can represent the sound pressure value of each element in one dimension direction of the corresponding three-dimensional matrix, so that by determining the sound pressure value of each position corresponding to each element of the three-dimensional matrix on the plurality of preset paths, the sound pressure value of each element in the three-dimensional direction of the three-dimensional matrix can be determined, and thus the sound pressure value of each element of the three-dimensional matrix can be determined.

[0091] In an embodiment of the present application, emitting a detection light beam along a plurality of preset paths in the three-dimensional direction of the three-dimensional matrix can specifically include:

[0092] setting a first plane perpendicular to the projection plane of the sound field of the to-be-tested sound wave;

[0093] making the to-be-tested sound wave complete one rotation by multiple rotations;

[0094] emitting a detection light beam along a preset path perpendicular to the first plane between adjacent two rotations of the to-be-tested sound wave and after one rotation, and making the detection light beam scan the first plane.

[0095] For example, when the to-be-tested acoustic wave is not self-rotating, the self-rotation angle of the to-be-tested acoustic wave is 0°, at this time, the detection light beam can be emitted along a preset path perpendicular to the first plane (for example, as shown in the first plane in which the direction x and the direction y in FIGS. 3-5) for the first time, and the detection light beam is scanned along the first plane for the first time. The detection light beam emitted along a preset path perpendicular to the first plane can penetrate a plurality of elements in a dimension direction of the three-dimensional matrix corresponding to the preset path, and the detection light beam is scanned along the first plane, and the projection distribution of the acoustic pressure gradient of the to-be-tested acoustic wave field on the first plane can be determined, that is, the projection distribution of the refractive index gradient of the auxiliary medium on the first plane can be determined. Then, the to-be-tested acoustic wave can be self-rotated by, for example, 0.01°-1°, and the detection light beam can be emitted along a preset path perpendicular to the first plane for the second time, and the detection light beam is scanned along the first plane for the second time, until the to-be-tested acoustic wave is self-rotated by 360°, and the detection light beam is emitted along a preset path perpendicular to the first plane for the last time, and the detection light beam is scanned along the first plane for the last time. In this way, the projection distribution of the acoustic pressure gradient of the to-be-tested acoustic wave field on the first plane when the to-be-tested acoustic wave is self-rotated to different angles can be determined, and then the projection distribution of the acoustic pressure gradient of the to-be-tested acoustic wave field on the first plane when the to-be-tested acoustic wave is self-rotated to different angles can be calculated by a tomographic reconstruction algorithm, so that the acoustic pressure value of each element of the three-dimensional matrix can be determined.

[0096] In an embodiment of the present application, emitting the detection light beam along a preset path perpendicular to the first plane and scanning the detection light beam along the first plane can specifically include:

[0097] A plurality of path groups are set, each path group includes a plurality of preset paths, and the plurality of preset paths in the same path group are distributed at intervals in a first direction of the first plane perpendicular to the projection plane of the to-be-tested acoustic wave field, and the path groups are distributed at intervals in a second direction of the first plane perpendicular to the first direction.

[0098] The detection light beam is emitted in sequence according to the order of the plurality of path groups.

[0099] In actual application, taking the plane in which the direction x and the direction y in the figure are located as the first plane as an example, the plurality of preset paths in the same path group can be distributed at intervals in the direction x (i.e., the first direction), the different path groups can be distributed at intervals in the direction y (i.e., the second direction), and in the process of causing the detection light beam to scan the first plane, the detection light beam can be first emitted along the plurality of preset paths in one path group, that is, the detection light beam is first emitted along the plurality of preset paths distributed at intervals in the direction x, that is, the detection light beam is first caused to scan in the direction x, and then the detection light beam is emitted along the plurality of preset paths in another path group adjacent to the one path group, that is, the detection light beam is emitted along the plurality of preset paths distributed at intervals in the direction y, that is, the detection light beam is caused to scan in the direction y again, so that the detection light beam scans the plane in which the direction x and the direction y are located (i.e., the first plane).

[0100] As shown in FIG. 2, the embodiment of the present application further provides a sound pressure measuring device for executing the sound pressure measuring method provided by the embodiment of the present application. The sound pressure measuring device comprises a light source 1, an acquisition component 2 and a controller 3. The light source 1 is used for emitting a detection light beam, the acquisition component 2 is used for acquiring the detection light beam, and the controller 3 is in signal connection with the light source 1 and the acquisition component 2 respectively and is used for controlling the start and stop of the light source 1 and the acquisition of the detection light beam by the acquisition component 2.

[0101] The sound pressure measuring device provided by the embodiment of the present application can improve the sound pressure measuring accuracy, the measuring range and the spatial resolution by executing the sound pressure measuring method provided by the embodiment of the present application, so as to meet the measuring requirement of the sound field sound pressure of HIFU.

[0102] Optionally, the light source 1 can comprise a laser.

[0103] Optionally, the laser can be a continuous laser capable of continuously emitting a laser beam.

[0104] Optionally, the acquisition component 2 can comprise an intensified charge coupled device (ICCD) camera.

[0105] In actual application, the ICCD camera has a very short shutter time, and the shooting time and the shutter size can be accurately controlled (the accuracy can reach the nanosecond level) through signal triggering, so as to complete the instantaneous acquisition of the detection light beam. When the to-be-measured sound wave is not loaded, the detection light beam can be irradiated at the center of the ICCD camera, i.e., the origin position. When the to-be-measured sound wave is loaded, the irradiation position and the illumination distribution of the detection light beam will change with the change of the period of the to-be-measured sound wave (i.e., the irradiation position offset and the illumination deviation), and through the control of the shooting time and the shutter size of the ICCD camera, the change process of the detection light beam with the period of the to-be-measured sound wave can be acquired, so as to determine the sound field sound pressure distribution of the to-be-measured ultrasonic wave.

[0106] As shown in Fig. 2, in an embodiment of the present application, the sound pressure measuring device can further comprise a first moving component 4, a second moving component 5 and a rotating component 6, the first moving component 4 is connected with the light source 1 and is used to drive the light source 1 to move in a first direction and a second direction, the first direction and the second direction are perpendicular and are located on a first plane which is perpendicular to a projection plane of the sound field of the sound wave to be measured, the second moving component 5 is connected with the collecting component 2 and moves synchronously with the first moving component 4, and is used to drive the collecting component 2 to move synchronously with the light source 1, the rotating component 6 is connected with the sound source 10 which provides the sound wave to be measured, and is used to drive the sound source 10 to rotate.

[0107] The light source 1 is driven by the first moving component 4 to move in the first direction and the second direction, so that the detection light beam can be scanned in the first direction and the second direction, thereby the detection light beam can be scanned on the first plane, the collecting component 2 is driven by the second moving component 5 to move synchronously with the light source 1, so that the relative position between the light source 1 and the collecting component 2 is unchanged when the light source 1 moves in the first direction and the second direction, thereby the position of the light source 1 on the collecting component 2 is unchanged, so that the detection light beam can always irradiate on the initial irradiation position through the auxiliary medium when the sound wave to be measured is not loaded, and further the determined irradiation position offset and the irradiance deviation value can be accurate. The sound source 10 is driven by the rotating component 6 to rotate, so that the sound wave to be measured can rotate.

[0108] Optionally, the sound source 10 can comprise a HIFU transducer.

[0109] As shown in Fig. 2, optionally, the first moving component 4 can comprise a first moving platform, and the light source 1 can be arranged above the first moving platform.

[0110] Optionally, the distance that the light source 1 is driven by the first moving component 4 to move in the first direction and the second direction can be equal to the diameter of the detection light beam, and is less than or equal to half of the wavelength of the sound wave to be measured.

[0111] Optionally, the moving precision that the light source 1 is driven by the first moving component 4 to move in the first direction and the second direction can be 0.01mm-0.05mm.

[0112] As shown in Fig. 2, optionally, the second moving component 5 can comprise a second moving platform, and the collecting component 2 can be arranged above the second moving platform.

[0113] Optionally, the distance that the light source 1 is driven by the second moving component 5 to move in the first direction and the second direction can be equal to the diameter of the detection light beam, and is less than or equal to half of the wavelength of the sound wave to be measured.

[0114] Optionally, the moving precision that the collecting component 2 is driven by the second moving component 5 to move in the first direction and the second direction can be 0.01mm-0.05mm.

[0115] As shown in FIG. 2, optionally, the rotating component 6 can comprise a rotating platform, and the sound source 10 can be arranged below the rotating platform.

[0116] Optionally, the rotating precision of the rotating component 6 driving the sound source 10 to rotate can be ±30".

[0117] As shown in FIG. 2, optionally, the controller 3 is signal connected with the first moving component 4, the second moving component 5 and the rotating component 6 respectively, for controlling the first moving component 4 to move, controlling the second moving component 5 to move, and controlling the rotating component 6 to rotate.

[0118] In an embodiment of the present application, the variation rate of the output power of the light source 1 can be less than or equal to 1%.

[0119] Such design is because the lower the variation rate of the output power of the light source 1, the better the output power stability of the light source 1, and the output power of the light source 1 will affect the illumination of the detection light beam, therefore, the better the output power stability of the light source 1, the more accurate and stable the obtained illumination deviation value, thereby the sound pressure measurement accuracy can be improved.

[0120] As shown in FIG. 2, optionally, the sound pressure measurement device can further comprise a signal generator 7 and a power amplifier 8, the controller 3, the signal generator 7, the power amplifier 8 and the sound source 10 are sequentially connected, and the controller 3 is configured to send a control signal to the signal generator 7, so as to send a control signal to the power amplifier 8 through the signal generator 7, thereby controlling the output power of the sound source 10 through the power amplifier 8.

[0121] As shown in FIG. 2, optionally, the sound pressure measurement device can further comprise a computer 9, the computer 9 can be provided with a processing module and a computer 9 readable storage medium, the processing module is signal connected with the controller 3 and the acquisition component 2 respectively, and the computer 9 readable storage medium stores a computer 9 program, and the computer 9 program can realize the sound pressure measurement method provided by the embodiment of the present application when executed by the processing module.

[0122] As shown in FIG. 2, optionally, the sound pressure measurement device can further comprise a holding component 11 for holding an auxiliary medium.

[0123] For example, taking water as the auxiliary medium, the holding component 11 can comprise a water tank. In actual application, the window glass of the water tank can be penetrated by the detection light beam, and the window glass needs to have good optical uniformity to avoid uneven deflection of the detection light beam when penetrating the window glass. In this case, the projection plane of the sound wave sound field to be measured can be, for example, the projection plane of the holding component 11 of the water tank, for example, the orthographic projection plane of the water tank.

[0124] As shown in FIG. 2, optionally, the sound pressure measuring device can further comprise a light beam adjusting assembly 12, the light source 1, the light beam adjusting assembly 12 and the containing component 11 are sequentially arranged, and the light beam adjusting assembly 12 can adjust the diameter of the detection light beam passing therethrough.

[0125] As shown in FIG. 2, optionally, the light beam adjusting assembly 12 can comprise a focusing lens 121, a pinhole filter 122, a collimating lens 123 and a grating (not shown in the figure), and the light source 1, the focusing lens 121, the pinhole filter 122, the collimating lens 123, the grating and the containing component 11 are sequentially arranged.

[0126] The embodiment of the present application further provides a computer 9 readable storage medium, the computer 9 readable storage medium stores a computer 9 program, and the computer 9 program can realize the sound pressure measuring method provided by the embodiment of the present application when executed by the processing module.

[0127] The computer 9 readable storage medium provided by the embodiment of the present application stores the computer 9 program which can realize the sound pressure measuring method provided by the embodiment of the present application when executed by the processing module, so that the sound pressure measuring accuracy, the measuring range and the spatial resolution can be improved, and the measuring requirement of the HIFU sound field sound pressure can be met.

[0128] In summary, the sound pressure measuring method, the sound pressure measuring device and the computer 9 readable storage medium provided by the embodiment of the present application can improve the sound pressure measuring accuracy, the measuring range and the spatial resolution, so that the measuring requirement of the HIFU sound field sound pressure can be met.

[0129] It can be understood that the above embodiments are only exemplary embodiments for illustrating the principles of the present application, and the present application is not limited thereto. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and essence of the present application, and these modifications and improvements are also regarded as the protection scope of the present application.

Claims

1. A sound pressure measurement method characterized by, The method comprises the following steps: firing a detection light beam along a preset path; when no sound wave to be measured is loaded, obtaining an initial irradiation position of the detection light beam and an initial irradiance of the initial irradiation position; when the sound wave to be measured is loaded, obtaining a deflected irradiation position of the detection light beam after penetrating the sound wave field to be measured and a deflection irradiance of the initial irradiation position; determining an irradiation position offset of the deflected irradiation position relative to the initial irradiation position and an irradiance deflection value of the deflection irradiance relative to the initial irradiance, and determining a sound pressure value of each position of the sound wave field to be measured on the preset path according to the irradiation position offset and the irradiance deflection value.

2. The acoustic impedance measurement method according to claim 1, characterized in that, The method further comprises the following steps: obtaining the deflected irradiation position of the detection light beam after penetrating the sound wave field to be measured and the deflection irradiance of the initial irradiation position in a plurality of to-be-measured time periods of the sound wave to be measured; The method further comprises the following steps: determining a plurality of irradiation position offsets of the deflected irradiation position relative to the initial irradiation position and a plurality of irradiance deflection values of the deflection irradiance relative to the initial irradiance, and determining a sound pressure value of each position of the sound wave field to be measured at a plurality of to-be-measured time periods on the preset path according to the plurality of irradiation position offsets and the plurality of irradiance deflection values corresponding to the plurality of to-be-measured time periods.

3. The acoustic manometry method of claim 2, wherein, The method further comprises the following steps: The measured refractive index of each position of the preset path at the plurality of to-be-measured time instants is determined according to a preset refractive index gradient integral relationship, and the sound pressure value is determined according to the measured refractive index, wherein the refractive index gradient integral relationship is: wherein a and b are correction coefficients relative to a standard sound wave of the sound wave to be measured, x is a coordinate in a first direction, y is a coordinate in a second direction, z is a coordinate in a third direction, the first direction and the second direction are perpendicular and located on a first plane perpendicular to a projection plane of the sound wave field to be measured, the third direction is perpendicular to the first plane, t is the to-be-measured time, ΔI is the irradiance deflection value, v is the irradiation position offset, L is a length of the sound wave field to be measured in the third direction, and ▽n is the refractive index gradient.

4. The acoustic manometry method of claim 3, wherein, The method further comprises the following steps: determining the sound pressure value according to the measured refractive index and a preset first relationship, the first relationship being: wherein n is the measured refractive index, n0is the refractive index of the medium to be measured loaded with the sound wave to be measured when not loaded with the sound wave to be measured, The photo-optical coefficient of a medium loaded by the sound wave to be measured, and p is the sound pressure value.

5. The acoustic impedance measurement method of claim 1, wherein, The detection light beam is a Gaussian light beam.

6. The acoustic manometry method of claim 5, wherein, The initial irradiation position and the deflected irradiation position of the Gaussian light beam are both irradiance peak positions of the Gaussian light beam.

7. The acoustic manometry method of claim 1, wherein, The method further comprises the following steps: setting a three-dimensional matrix for the sound wave field to be measured, and determining a sound pressure value of each element of the three-dimensional matrix.

8. The acoustic manometry method of claim 7, wherein, The setting of the three-dimensional matrix for the sound field of the to-be-tested sound wave specifically comprises: The detection light beams are emitted along the multiple preset paths in the three-dimensional direction of the three-dimensional matrix; The sound pressure values of each position on the multiple preset paths corresponding to each element of the three-dimensional matrix are determined.

9. The acoustic manometry method of claim 8, wherein, The emitting of the detection light beams along the multiple preset paths in the three-dimensional direction of the three-dimensional matrix specifically comprises: A first plane perpendicular to the projection plane of the to-be-tested sound wave is set; The to-be-tested sound wave is made to complete one revolution by multiple self-rotations; The detection light beams are emitted along preset paths perpendicular to the first plane between adjacent two self-rotations of the to-be-tested sound wave and after one revolution of the to-be-tested sound wave, and the detection light beams are made to scan the first plane.

10. The acoustic manometry method of claim 9, wherein, The emitting of the detection light beams along preset paths perpendicular to the first plane and the scanning of the first plane by the detection light beams specifically comprise: Multiple path groups are set, each of the path groups comprises multiple preset paths, the multiple preset paths of the same path group are distributed at intervals in a first direction of the first plane parallel to the projection plane of the to-be-tested sound wave, and the multiple path groups are distributed at intervals in a second direction of the first plane perpendicular to the first direction; The detection light beams are emitted in sequence according to the order of the multiple path groups.

11. A sound pressure measuring device, characterized by comprising: The sound pressure measuring device for performing the sound pressure measuring method according to any one of claims 1-10 comprises a light source, an acquisition component and a controller, the light source is used for emitting the detection light beams, the acquisition component is used for acquiring the detection light beams, and the controller is signal-connected with the light source and the acquisition component respectively and is used for controlling the start and stop of the light source and the acquisition of the detection light beams by the acquisition component.

12. The acoustic manometry device of claim 11, wherein, The sound pressure measuring device further comprises a first moving component, a second moving component and a rotating component, the first moving component is connected with the light source and is used for driving the light source to move in a first direction and a second direction, the first direction and the second direction are perpendicular and are located on a first plane perpendicular to the projection plane of the to-be-tested sound wave, the second moving component is connected with the acquisition component and moves synchronously with the first moving component, is used for driving the acquisition component to move synchronously with the light source, and the rotating component is connected with a sound source providing the to-be-tested sound wave and is used for driving the sound source to self-rotate.

13. The acoustic manometry device of claim 11, wherein, The variation rate of the output power of the light source is less than or equal to 1%.

14. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, and the computer program can implement the sound pressure measuring method according to any one of claims 1-10 when executed by a processing module.

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