Array element screening method and system for spherical multi-element array focusing ultrasonic transducer

Abstract

The application belongs to the technical field of spherical multi-piece array focusing ultrasonic transducer, and discloses a kind of array element screening method and system for spherical multi-piece array focusing ultrasonic transducer.The method first realizes the pre-screening of array element by comparing the measured value of array element quality factor with the threshold value of array element quality factor.On the basis of pre-screening, the combination of array elements with equal eigenfrequency is a group, and fine screening is realized.On the basis of fine screening, the measured deviation of the eigenfrequency of each array element and the base frequency is compared with the preset deviation of the eigenfrequency, and the fine screening of the fine screening array element group is realized to obtain the fine screening array element group.Based on this, it is ensured that the array elements in the fine screening array element group have good consistency of physical parameters and electrical parameters.In practical application, the equivalent array element group composed of array elements can have good consistency of output characteristic parameters, improving the efficiency and effect of cancer treatment.The application also provides an array element screening system including a parameter configuration unit, a pre-screening unit, a fine screening unit and a fine screening unit.

Description

Technical Field

[0001] This invention belongs to the field of ultrasonic transducer technology, and particularly relates to a method and system for selecting array elements for a spherical multi-slice array focused ultrasonic transducer. Background Technology

[0002] Focused ultrasonic transducers can be divided into two main categories based on the number of array elements: single-element focused ultrasonic transducers and multi-element focused ultrasonic transducers. Single-element focused ultrasonic transducers include two forms: planar inductors with acoustic lenses and self-focusing transducers. The technology of planar inductors with acoustic lenses is relatively mature, offering advantages such as ease of manufacturing and control, high focal power density, and easy focal length adjustment. However, it suffers from disadvantages such as low efficiency and the lens itself being prone to deformation. Self-focusing transducers easily achieve an ideal focal length shape; however, large-size, high-power piezoelectric transducers are easily broken, and the focal point and focal length cannot be adjusted.

[0003] Multi-element focused ultrasound transducers include two types: multi-element phased array focused ultrasound and spherical multi-element focused ultrasound. Multi-element phased array focused ultrasound offers advantages such as adjustable focal length, controllable focal shape, high transduction efficiency, and short treatment time; however, it also has disadvantages such as high development difficulty and immature technology. Spherical multi-element focused ultrasound offers high transduction efficiency, but it requires high consistency in the physical, electrical, and output characteristics of the array panels and / or elements.

[0004] In practical applications, spherical multi-element focused ultrasound transducers are required to have a fixed output frequency. Therefore, it is necessary to ensure that the multiple elements within the transducer have consistent physical, electrical, and output characteristic parameters. However, currently, the transducers included in the transducers are generally made of piezoelectric ceramics. The material, manufacturing process, and assembly process (specifically, the welding process of the transducers, base, and leads) can easily cause inconsistencies in these parameters. This can further affect the therapeutic efficacy of the spherical multi-element focused ultrasound transducer for treating diseases. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for screening array elements in a spherical multi-array focused ultrasound transducer. Pre-screening of array elements is achieved by comparing the measured values ​​of their quality factors with a threshold value. Based on this pre-screening, array elements with equal intrinsic frequencies are grouped together for fine screening. Further, based on this fine screening, the measured deviations of each element's intrinsic frequency from its fundamental frequency are compared with preset deviations to achieve precise screening of the array element groups. This ensures that the array elements within the finely screened groups have consistent physical and electrical parameters. In practical applications, the equivalent array element group composed of these elements can have consistent output characteristic parameters, thereby improving the efficiency and effectiveness of disease treatment.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a method for selecting array elements for a spherical multi-slice array focused ultrasound transducer, comprising the following steps:

[0008] Provides multiple array elements;

[0009] Determine the threshold for the array element quality factor, and measure and obtain the measured value of the array element quality factor;

[0010] Array elements whose measured quality factor is less than the array element quality factor threshold are removed, while array elements whose measured quality factor is greater than or equal to the array element quality factor threshold are retained to form a pre-screened array element group.

[0011] Measure and obtain the eigenfrequency, impedance, and impedance angle of the array elements in the pre-screened array;

[0012] A fine-sieve array element group is formed by at least two array elements with equal intrinsic frequencies, thus forming multiple fine-sieve array element groups corresponding to multiple intrinsic frequencies.

[0013] Select one intrinsic frequency from multiple intrinsic frequencies as the fundamental frequency, determine the measured deviations of other intrinsic frequencies from the fundamental frequency based on the fundamental frequency, and configure the preset deviation of the intrinsic frequency.

[0014] Select a fine sieve array from multiple fine sieve arrays where the measured deviation is less than or equal to the preset deviation and the number of array elements in the fine sieve array is greater than or equal to the preset number, to obtain multiple fine sieve arrays.

[0015] As one possible implementation, the array element includes a diaphragm, a diaphragm base, and leads; before providing multiple array elements, the array element selection method further includes selecting the diaphragm based on physical parameters, including the diaphragm thickness and the diaphragm diameter; the diaphragm selection based on physical parameters includes the following steps:

[0016] The thickness range of the transducer is determined based on the operating frequency of the spherical multi-plate array focused ultrasonic transducer, and transducers within the thickness range are retained.

[0017] The diameter range of the transducers is determined based on the effective transducer area of ​​the spherical bracket included in the spherical multi-element array focused ultrasound transducer and the required number of array elements. Transducers within the diameter range are retained.

[0018] As one possible implementation, after selecting the oscillators based on physical parameters, the array element selection method also includes: selecting oscillators based on electrical parameters, including quality factor, eigenfrequency, impedance, and impedance angle; the specific steps for selecting oscillators based on electrical parameters are as follows:

[0019] Determine the quality factor threshold for the diaphragm and retain diaphragms that are greater than or equal to the quality factor threshold.

[0020] Obtain the eigenfrequency, impedance, and impedance angle of each oscillator obtained in the previous step;

[0021] Select the intrinsic frequency from the intrinsic frequencies of multiple oscillators as the fundamental frequency, determine the measured deviation between the intrinsic frequencies of the remaining oscillators and the fundamental frequency based on the fundamental frequency, and configure the preset deviation.

[0022] Select a diaphragm from the diaphragms obtained in the previous step whose measured deviation is less than or equal to the preset deviation.

[0023] As one possible implementation, the intrinsic frequencies, impedances, and impedance angles of the array elements in the pre-screened array are measured and obtained, specifically including the following steps:

[0024] The frequency-impedance curve of each element in the pre-screening array was obtained by using a frequency sweeping method.

[0025] Eliminate array elements with frequency-impedance curves that have double peaks, multiple peaks, or no peaks, while retaining array elements with frequency-impedance curves that have single peaks.

[0026] The intrinsic frequency, impedance, and impedance angle of the corresponding array element are obtained by measuring the frequency-impedance curve with a single peak value.

[0027] As one possible implementation, after obtaining multiple refined array elements, the array element selection method also includes:

[0028] Construct multiple identical equivalent matrix elements. For each equivalent matrix element, the construction method is as follows:

[0029] Determine the number of array elements required in the equivalent array element set;

[0030] At least one array element is selected from each finely screened array element group, and the total number of array elements selected from all finely screened array elements is equal to the number of array elements required in the equivalent array element group; the equivalent array element group is composed of multiple array elements selected from finely screened array element groups corresponding to different intrinsic frequencies.

[0031] As one possible implementation, the array elements in each equivalent array element group have the same intrinsic frequency components, the same termination equivalent impedance, and an impedance angle within a preset deviation range.

[0032] The termination equivalent impedance is determined by the impedance of the array elements in the equivalent array element group and the connection relationship. That is, when the array elements in the equivalent array element group are connected in series, the equivalent impedance is the total series impedance of all array elements.

[0033] When the array elements in the equivalent array are connected in parallel, the equivalent impedance is the total parallel impedance of all array elements.

[0034] When the array elements in the equivalent array are mixed, the equivalent impedance is the total impedance of the mixed array elements.

[0035] As one possible implementation, the total number of array elements in all equivalent array elements is greater than or equal to 50.

[0036] As one possible implementation, the intrinsic frequency preset deviation is less than or equal to 50kHz.

[0037] As one possible implementation, the quality factor threshold is greater than or equal to 500.

[0038] Secondly, the present invention also provides an array element screening system for a spherical multi-slice array focused ultrasound transducer, the array element screening system comprising:

[0039] The parameter configuration unit is used to configure the array element quality factor threshold, the intrinsic frequency preset deviation, and the impedance angle preset deviation.

[0040] The pre-screening unit is used to obtain the measured values ​​of the array element quality factor and remove array elements whose measured values ​​are less than the array element quality factor threshold. That is, it retains array elements whose measured values ​​are greater than or equal to the array element quality factor threshold to output the pre-screened array element group.

[0041] The fine screening unit is used to measure and obtain the eigenfrequency, impedance and impedance angle of the array elements in the pre-screening array element group, and to combine at least two array elements with the same eigenfrequency into a fine screening array element group. Multiple eigenfrequency correspondences form multiple fine screening array element groups.

[0042] The fine screening unit is used to select a fundamental frequency from multiple intrinsic frequencies and determine the measured deviation between the remaining intrinsic frequencies and the fundamental frequency based on the fundamental frequency; it selects a fine screening array element group from multiple fine screening array elements whose measured deviation is less than or equal to a preset deviation and whose number of array elements in the fine screening array element group is greater than or equal to a preset number, so as to output multiple fine screening array elements.

[0043] Compared with the prior art, the present invention has the following advantages:

[0044] 1. Pre-screening of array elements is achieved by comparing the measured values ​​of their quality factors with the threshold values. Based on this pre-screening, array elements with equal intrinsic frequencies are grouped together for further fine-tuning. Further, based on this fine-tuning, the measured deviations of each element's intrinsic frequency from its fundamental frequency are compared with preset deviations to achieve precise screening of the array element groups. This ensures that the array elements within the finely screened groups have consistent physical and electrical parameters. In practical applications, the equivalent array element groups formed by these elements can exhibit consistent output characteristic parameters, thereby improving the efficiency and effectiveness of cancer treatment.

[0045] 2. Before pre-screening, fine screening, and precision screening of the array elements, the core component of the array elements, the vibrating plate, is screened sequentially from both physical and electrical parameter perspectives to ensure the consistency of the core component parameters.

[0046] 3. After obtaining the finely screened array elements, multiple identical equivalent array elements are constructed. These equivalent array elements are composed of multiple array elements selected from the finely screened array elements corresponding to different intrinsic frequencies. Furthermore, the array elements in the equivalent array elements have the same intrinsic frequency components, the same equivalent termination impedance, and impedance angles within a preset deviation range. In practical applications, this ensures the consistency of the output characteristic parameters of each equivalent array elements. Attached Figure Description

[0047] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention.

[0048] Figure 1 This is a flowchart of the array element selection method for a spherical multi-slice array focused ultrasound transducer provided in an embodiment of the present invention;

[0049] Figure 2 This is a frequency-impedance curve with double peaks in an embodiment of the present invention;

[0050] Figure 3 This is a frequency-impedance curve without peak values ​​in an embodiment of the present invention;

[0051] Figure 4 This is a frequency-impedance curve with a single peak value in an embodiment of the present invention;

[0052] Figure 5 This is a block diagram of an array element screening system for a spherical multi-slice array focused ultrasound transducer provided in an embodiment of the present invention. Detailed Implementation

[0053] To facilitate a clear description of the technical solutions in the embodiments of the present invention, the terms "first" and "second" are used to distinguish identical or similar items with essentially the same function and effect. For example, the first threshold and the second threshold are merely used to distinguish different thresholds and do not limit their order. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that the terms "first" and "second" are not necessarily different.

[0054] It should be noted that in this invention, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0055] In this invention, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, a combination of a and b, a combination of a and c, a combination of b and c, or a, b, and c, where a, b, and c can be single or multiple.

[0056] In a first aspect, embodiments of the present invention provide a method for selecting array elements for a spherical multi-slice array focused ultrasound transducer, to solve at least one technical problem mentioned in the background art. See also Figure 1 The array element screening method provided in this embodiment of the invention includes the following steps:

[0057] S10. Provides array elements.

[0058] As an example, the number of array elements provided in this step can be 2,000 to 5,000 to ensure that the number of array elements selected in the end can meet the needs of actual applications, that is, the selection sample provided in this step is large enough.

[0059] In practical applications, S10 may specifically include the following sub-steps:

[0060] S100. Provides multiple oscillators. It needs further explanation that the oscillators are a core component of the array elements. Specifically, the oscillators can be piezoelectric ceramic oscillators, and their number can be 50 to 500 more than the number of array elements required by S10. For example, when S10 requires 2000 array elements, the number of oscillators can be 2050 to 2500. Or, when S10 requires 3000 array elements, the number of oscillators can be 3050 to 3500. Or, when S10 requires 5000 array elements, the number of oscillators can be 5050 to 5500. This arrangement ensures that after multiple rounds of screening, the number of remaining oscillators is equal to or slightly more than the number of array elements required by S10.

[0061] S101. Determine the thickness range of the transducer based on the operating frequency of the spherical multi-element array focused ultrasonic transducer, and obtain the measured thickness value of each transducer; retain the transducers whose measured thickness values ​​are within the thickness range.

[0062] It's important to further explain that the thickness of the transducer is highly correlated with the transmission frequency (operating frequency) of the ultrasound transducer. A thicker transducer results in a lower transmission frequency, while a thinner transducer results in a higher transmission frequency. Therefore, the transmission frequency must first be determined based on the data of the target tissue to be treated, and then an appropriate transducer thickness can be selected based on that frequency. As an example, when the target tissue data is basically determined, a transmission frequency of 1MHz can be chosen to ensure the effectiveness of ultrasound treatment. A transmission frequency greater than 1MHz results in weaker penetration of the ultrasound waves, posing a risk of not being able to penetrate the skin for treatment; while a transmission frequency less than 1MHz results in a too-large focal point, leading to problems with precise treatment.

[0063] When the transmission frequency is determined to be 1MHz, a transducer with an intrinsic frequency range of 1.0–1.1MHz can be selected. Based on this, the thickness range of the transducer can be determined to be 2.0–2.2mm. The actual thickness value of each transducer is obtained by measurement, and then each transducer is checked to see if its actual thickness value falls within the range. For example, if the actual thickness value of a transducer is 1.9mm, that transducer is discarded. Conversely, if the actual thickness value of a transducer is 2.0mm, that transducer is retained. In other words, this step removes all transducers whose actual thickness values ​​are outside the range, while retaining all transducers whose actual thickness values ​​are within the range.

[0064] S102. Determine the diameter range of the transducers based on the effective transducer area of ​​the spherical bracket included in the spherical multi-element array focused ultrasound transducer and the required number of array elements, and obtain the measured diameter value of each transducer obtained in the previous step; retain the transducers whose measured diameter values ​​are within the diameter range.

[0065] It's important to further explain that the choice of transducer diameter should also be within a reasonable range; too large or too small a diameter will significantly increase the transducer's production cost. Furthermore, the transducer diameter affects the effective transduction area of ​​the focused ultrasound transducer. A larger transducer diameter results in a smaller effective transduction area. Conversely, a smaller transducer diameter leads to a larger effective area, but this also increases the number of drive circuits required. Therefore, the selection of a single transducer diameter requires consideration of multiple factors.

[0066] As an example, the diameter can be in the range of 15.5 to 16.5 mm. Vibrators with a measured diameter less than 15.5 mm or greater than 16.5 mm are discarded, and vibrators with a measured diameter in the range of 15.5 to 16.5 mm are retained.

[0067] Up to S102, the coarse screening of the two rollers of the vibrator is completed using the physical parameters (thickness and diameter) of the vibrator.

[0068] S103. Determine the quality factor threshold of the diaphragm and obtain the measured quality factor value of the diaphragm obtained in the previous step; retain the diaphragms whose measured quality factor value is greater than or equal to the quality factor threshold of the diaphragm.

[0069] It's important to explain that the quality factor affects the operating temperature of a focused ultrasound transducer. Therefore, based on the transducer's temperature limit, a quality factor threshold of 500 is set for the transducer. Transducers with a quality factor less than 500 are more likely to heat up to or exceed their temperature limit when used in a focused ultrasound transducer. Conversely, transducers with a quality factor greater than or equal to 500 are less likely to reach or exceed their temperature limit when used in a focused ultrasound transducer. Therefore, by measuring the quality factor of each transducer after the previous screening step, transducers with a quality factor greater than or equal to 500 are retained, while those with a quality factor less than 500 are discarded.

[0070] Step S103 involves using one of the electrical parameters of the vibrator (quality factor) to complete the first round of fine sieving of the vibrator.

[0071] S104. Obtain the eigenfrequency, impedance, and impedance angle of each oscillator obtained in the previous step.

[0072] As an example, any existing frequency sweeping instrument can be used to sweep the frequency of each oscillator obtained in the previous step to obtain the frequency-impedance curve of each oscillator. In practice, it has been found that the obtained frequency-impedance curve may take several forms:

[0073] Right now Figure 2 The frequency-impedance curve shown has two peaks. Figure 3 The frequency-impedance curves with multiple peaks shown, and Figure 4 The frequency-impedance curve shown has a single peak value.

[0074] The intrinsic frequency, impedance, and impedance angle of the oscillator cannot be accurately measured by frequency-impedance curves with double or multiple peaks. Therefore, the oscillators corresponding to frequency-impedance curves with double or multiple peaks are eliminated, and only the oscillators corresponding to frequency-impedance curves with single peaks are retained. The intrinsic frequency, impedance, and impedance angle of the oscillator are then determined based on the frequency-impedance curve with single peaks.

[0075] S105. Select one intrinsic frequency from multiple oscillators as the fundamental frequency, determine the measured deviation between the intrinsic frequencies of other oscillators and the fundamental frequency of the oscillators based on the fundamental frequency of the oscillators, and configure the preset deviation.

[0076] As an example, the eigenfrequencys of 3000 oscillators are measured, with these frequencies distributed between 1.049 and 1.080 MHz. The fundamental frequency is determined by comprehensively considering the number of array elements at each eigenfrequency point and the concentration of these eigenfrequency points. The maximum value of the preset deviation can be 50 kHz.

[0077] S106. Select a diaphragm from the diaphragms obtained in the previous step whose measured deviation is less than or equal to the preset deviation.

[0078] As an example, when the fundamental frequency is 1.051MHz, oscillators with intrinsic frequencies of 1.049MHz, 1.050MHz, 1.052MHz, and 1.053MHz are all effective oscillators that are desired.

[0079] Steps S104 to S106 involve using one of the electrical parameters of the vibrator (intrinsic frequency) to complete the first round of fine screening of the vibrator.

[0080] S107. Assemble the diaphragm obtained in the previous step with the base and lead wires to form an array element. The specific assembly method described above can be welding, which will not be described in detail here.

[0081] In this embodiment of the invention, before pre-screening, fine screening, and precision screening of the array elements, the core component diaphragms of the array elements, S100 to S107, are used to sequentially screen from both physical and electrical parameter perspectives to ensure the consistency of the core component parameters.

[0082] Considering the adverse effects of welding the vibrator to the base and lead wires on the electrical parameters of the final array element, the following steps are required to perform pre-screening, fine screening, and precision screening on the array element again.

[0083] S11. Determine the threshold for the array element quality factor, and measure and obtain the measured value of the array element quality factor.

[0084] The temperature rise of a focused ultrasound transducer during operation must not be too high, meaning it must not exceed the transducer's temperature limit. The quality factor directly affects the operating temperature of the focused ultrasound transducer. Therefore, a quality factor threshold of 500 can be determined based on the temperature limit. Element quality factors with a quality factor less than 500, when used in a focused ultrasound transducer, are more likely to cause the transducer to heat up to or exceed its temperature limit. Conversely, element quality factors greater than or equal to 500, when used in a focused ultrasound transducer, have a lower probability of causing the transducer to heat up to its temperature limit.

[0085] The measured value of the array element quality factor can be obtained using any method provided by existing technology.

[0086] S12. Array elements whose measured quality factor is less than the array element quality factor threshold are removed, that is, array elements whose measured quality factor is greater than or equal to the array element quality factor threshold are retained to form a pre-screened array element group.

[0087] Therefore, by measuring the measured quality factor of each array element after the previous screening step, array elements with a measured quality factor greater than or equal to 500 are retained, while array elements with a measured quality factor less than 500 are removed.

[0088] S13. Measure and obtain the eigenfrequency, impedance, and impedance angle of the array elements in the pre-screened array element group.

[0089] S13 specifically includes the following steps:

[0090] S130. The frequency-impedance curve of each element in the pre-screened array is obtained by using the frequency sweep method.

[0091] S131. Eliminate array elements corresponding to frequency-impedance curves with double peaks, multiple peaks, or no peaks, i.e., retain array elements corresponding to frequency-impedance curves with single peaks.

[0092] S132. Based on the frequency-impedance curve with a single peak, the eigenfrequency, impedance, and impedance angle of the corresponding array element are measured and obtained.

[0093] S14. A fine-sieve array element group is formed by at least two array elements with equal intrinsic frequencies, and multiple fine-sieve array element groups are formed by corresponding intrinsic frequencies.

[0094] As an example, the eigenfrequency, impedance, and impedance angle values ​​of each array element can be obtained using a single-peak frequency-impedance curve, as shown in the table below (the electrical parameters in the table are those of elements with impedance angles greater than 20° and quality factors less than 500, excluding those with impedance angles greater than 20°).

[0095] Table 1 shows the eigenfrequency, impedance, and impedance angle of the array elements in the pre-screened array element group.

[0096] 7612 1.049 13.435 4.473 6751 1.049 23.048 0.214 7862 1.049 23.920 0.214 6921 1.049 17.901 -7.756 7997 1.049 19.030 4.259 …… …… …… …… 6484 1.050 14.303 1.536 6326 1.050 20.367 -10.399 6331 1.050 20.494 1.13 6366 1.050 20.516 -4.592 6461 1.050 21.281 0.305 …… …… …… …… 6639 1.051 14.737 1.799 …… …… …… …… 6156 1.052 14.820 2.811 …… …… …… …… 6328 1.053 20.305 -6.418 …… …… …… …… 6093 1.054 27.082 -8.21576 …… …… …… …… 7467 1.055 14.629 2.76031 …… …… …… ……

[0097] S15. Select one intrinsic frequency from multiple intrinsic frequencies as the fundamental frequency, and determine the measured deviation between the remaining intrinsic frequencies and the fundamental frequency based on the fundamental frequency. Configure the preset deviation of the intrinsic frequencies.

[0098] The principles for selecting the fundamental frequency include:

[0099] First, the number of array elements corresponding to the basic frequency is relatively large;

[0100] Second, the deviation of the intrinsic frequencies close to the fundamental frequency is small;

[0101] Third, there are a large number of array elements corresponding to eigenfrequency close to the fundamental frequency.

[0102] As an example, the intrinsic frequency distribution and the number of array elements corresponding to each intrinsic frequency (the number of array elements is in parentheses) are 1.049MHz (12), 1.050MHz (12), 1.051MHz (24), 1.052MHz (12), 1.053MHz (12), 1.054MHz (2), 1.055MHz (24), 1.056MHz (6), 1.057MHz (3), 1.058MHz (50), 1.059MHz (7), 1.060MHz (2), 1.061MHz (1), 1.062MHz (8)……1.100MHz (3).

[0103] When the selected intrinsic frequencies consist of 5 components, considering the small deviation of the intrinsic frequencies, there is no difference between 1.049–1.053MHz and 1.054–1.058MHz. However, considering the number of array elements, the number of array elements corresponding to each intrinsic frequency in the 1.049–1.053MHz frequency range is relatively balanced, while the balance is poor in the 1.054–1.058MHz frequency range. For example, the 1.055MHz intrinsic frequency corresponds to 24 array elements, while the 1.054MHz intrinsic frequency corresponds to only 2 array elements. Therefore, in this embodiment, a fundamental frequency should be determined within the 1.049–1.053MHz range, which is 1.051MHz. It should be understood that this embodiment is only an explanatory description for ease of understanding and is not intended to be limiting.

[0104] The maximum value of the preset deviation of the intrinsic frequency of the array element can be set to 50kHz.

[0105] S16. Select a fine sieve array element group from multiple fine sieve array element groups where the measured deviation is less than or equal to the preset deviation of the intrinsic frequency and the number of array elements in the fine sieve array element group is greater than or equal to the preset number, so as to obtain multiple fine sieve array element groups.

[0106] Continuing with the example in S15, the maximum preset deviation of the intrinsic frequency can be 50kHz, the preset number can be 50, and the number of fine-screened array elements is 5. The resulting 5 sets of fine-screened array elements are shown in Table 2.

[0107] Table 2 Fine Screening Array Components

[0108]

[0109]

[0110] As one possible implementation, after obtaining multiple refined array elements, the array element selection method also includes:

[0111] S17. Construct multiple identical equivalent matrix elements. For each equivalent matrix element, the construction method is as follows:

[0112] S170. Determine the number of array elements required in the equivalent array element set.

[0113] S171. Select at least one array element from each finely screened array element group, and the total number of array elements selected from all finely screened array elements is equal to the number of array elements required in the equivalent array element group; the equivalent array element group is composed of multiple array elements selected from finely screened array element groups corresponding to different intrinsic frequencies.

[0114] As an example, 12 equivalent array element groups need to be constructed, with 6 array elements required in each equivalent array element group. In this case, for each equivalent array element, one array element can be selected from the 1.049MHz intrinsic frequency, one array element can be selected from the 1.050MHz intrinsic frequency, two array elements can be selected from the 1.051MHz intrinsic frequency, one array element can be selected from the 1.052MHz intrinsic frequency, and one array element can be selected from the 1.053MHz intrinsic frequency.

[0115] It needs further explanation that the intrinsic frequency of 1.049MHz corresponds to 12 array elements, 1.050MHz corresponds to 12 array elements, 1.051MHz corresponds to 24 array elements, 1.052MHz corresponds to 12 array elements, and 1.053MHz corresponds to 12 array elements. Therefore, the specific array element selected within each equivalent array element group corresponding to each intrinsic frequency requires comprehensive consideration of the magnitude of the short-circuit equivalent impedance deviation of the equivalent array element group and whether the impedance angle is less than 20°.

[0116] Continuing from the example in S16, and with the array elements in each equivalent array set connected in parallel in practical applications, the final 12 equivalent array sets are as follows:

[0117] Table 3. Equivalent Array Element Group 1

[0118]

[0119] Table 4. Equivalent Array Element Group 2

[0120]

[0121] Table 5. Equivalent Array Element Group 3

[0122]

[0123] Table 6. Equivalent Array Element Group 4

[0124]

[0125] Table 7. Equivalent Array Element Group 5

[0126]

[0127] Table 8. Equivalent Array Element Group 6

[0128]

[0129] Table 9. Seventh Group of Equivalent Array Elements

[0130]

[0131]

[0132] Table 10. Group 8 Equivalent Array Elements

[0133]

[0134] Table 11 Equivalent Array Element Group 9

[0135]

[0136] Table 12 Equivalent Array Element Group 10

[0137]

[0138] Table 13 Group 11 Equivalent Array Elements

[0139]

[0140]

[0141] Table 14, Group Twelve: Equivalent Array Elements

[0142]

[0143] The maximum equivalent impedance error of the 12 groups is less than the preset threshold (the preset threshold is 10Ω). In this data, the maximum short-circuit equivalent impedance error is 0.586Ω, which is less than the preset threshold of 10Ω. The impedance angle is less than 20°.

[0144] As one possible implementation, the array elements in each equivalent array element group have the same intrinsic frequency components, the same termination equivalent impedance, and the impedance angle within a preset deviation range; the termination equivalent impedance is determined by the impedance of the array elements in the equivalent array element group and the connection relationship.

[0145] As one possible implementation, the termination equivalent impedance is determined as follows:

[0146] When the array elements in the equivalent array are connected in series, the equivalent impedance is the total series impedance of all array elements.

[0147] When the array elements in the equivalent array are connected in parallel, the equivalent impedance is the total parallel impedance of all array elements.

[0148] When the array elements in the equivalent array are mixed, the equivalent impedance is the total impedance of the mixed array elements.

[0149] As one possible implementation, the total number of array elements in all equivalent array elements is greater than or equal to 50.

[0150] As one possible implementation, the intrinsic frequency preset deviation is less than or equal to 50kHz.

[0151] As one possible implementation, the quality factor threshold is greater than or equal to 500.

[0152] Secondly, see Figure 5 The present invention also provides an array element selection system for a spherical multi-slice array focused ultrasound transducer, the array element selection system comprising:

[0153] The parameter configuration unit is used to configure the array element quality factor threshold, the intrinsic frequency preset deviation, and the impedance angle preset deviation.

[0154] The pre-screening unit is used to obtain the measured values ​​of the array element quality factor and remove array elements whose measured values ​​are less than the array element quality factor threshold. That is, it retains array elements whose measured values ​​are greater than or equal to the array element quality factor threshold to output the pre-screened array element group.

[0155] The fine screening unit is used to measure and obtain the eigenfrequency, impedance and impedance angle of the array elements in the pre-screening array element group, and to combine at least two array elements with the same eigenfrequency into a fine screening array element group. Multiple eigenfrequency correspondences form multiple fine screening array element groups.

[0156] The fine screening unit is used to select a fundamental frequency from multiple intrinsic frequencies and determine the measured deviation between the remaining intrinsic frequencies and the fundamental frequency based on the fundamental frequency; it selects a fine screening array element group from multiple fine screening array elements whose measured deviation is less than or equal to a preset deviation and whose number of array elements in the fine screening array element group is greater than or equal to a preset number, so as to output multiple fine screening array elements.

[0157] Compared with the prior art, the present invention has the following advantages:

[0158] 1. Pre-screening of array elements is achieved by comparing the measured values ​​of their quality factors with the threshold values. Based on this pre-screening, array elements with equal intrinsic frequencies are grouped together for further fine-tuning. Further, based on this fine-tuning, the measured deviations of each element's intrinsic frequency from its fundamental frequency are compared with preset deviations to achieve precise screening of the array element groups. This ensures that the array elements within the finely screened groups have consistent physical and electrical parameters. In practical applications, the equivalent array element groups formed by these elements can exhibit consistent output characteristic parameters, thereby improving the efficiency and effectiveness of cancer treatment.

[0159] 2. Before pre-screening, fine screening, and precision screening of the array elements, the core component of the array elements, the vibrating plate, is screened sequentially from both physical and electrical parameter perspectives to ensure the consistency of the core component parameters.

[0160] 3. After obtaining the finely screened array elements, multiple identical equivalent array elements are constructed. These equivalent array elements are composed of multiple array elements selected from the finely screened array elements corresponding to different intrinsic frequencies. Furthermore, the array elements in the equivalent array elements have the same intrinsic frequency components, the same equivalent termination impedance, and impedance angles within a preset deviation range. In practical applications, this ensures the consistency of the output characteristic parameters of each equivalent array elements.

[0161] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, the disclosure, and the appended claims in carrying out the claimed invention. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce good results.

[0162] Although the invention has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made therein without departing from the spirit and scope of the invention. Accordingly, this specification and drawings are merely exemplary descriptions of the invention as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if such modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include such modifications and modifications.

Claims

1. A method for selecting array elements for a spherical multi-slice array focused ultrasound transducer, characterized in that, Includes the following steps: Provides multiple array elements; Determine the threshold for the array element quality factor, and measure and obtain the measured value of the array element quality factor; The array elements whose measured quality factor is less than the array element quality factor threshold are removed, while the array elements whose measured quality factor is greater than or equal to the array element quality factor threshold are retained to form a pre-screened array element group. Measure and obtain the eigenfrequency, impedance, and impedance angle of the array element in the pre-screened array element group; A fine-sieve array element group is formed by at least two array elements with equal intrinsic frequencies, thereby forming multiple fine-sieve array element groups corresponding to multiple intrinsic frequencies. Select one intrinsic frequency from multiple intrinsic frequencies as the fundamental frequency, and determine the measured deviation of other intrinsic frequencies from the fundamental frequency based on the fundamental frequency; Configure the intrinsic frequency preset deviation; Multiple fine sieve arrays are obtained by selecting fine sieve arrays from multiple fine sieve arrays whose measured deviation is less than or equal to a preset deviation and whose number of array elements is greater than or equal to a preset number.

2. The element selection method for a spherical multi-array focused ultrasonic transducer according to claim 1, characterized in that, The array element includes a vibrator, a vibrator base, and leads; before providing multiple array elements, the array element selection method further includes selecting vibrator based on physical parameters, including vibrator thickness and vibrator diameter; selecting vibrator based on physical parameters includes the following steps: The thickness range of the transducer is determined based on the operating frequency of the spherical multi-plate array focused ultrasonic transducer, and transducers within the thickness range are retained. The diameter range of the transducer is determined based on the effective transducer area of ​​the spherical bracket included in the spherical multi-element array focused ultrasound transducer and the required number of array elements, and transducers within the diameter range are retained.

3. The element selection method for a spherical multi-array focused ultrasonic transducer according to claim 2, characterized in that, Following the selection of oscillators based on physical parameters, the array element selection method further includes: selecting oscillators based on electrical parameters, including quality factor, eigenfrequency, impedance, and impedance angle; the selection of oscillators based on electrical parameters specifically includes the following steps: Determine the quality factor threshold for the diaphragm and retain diaphragms that are greater than or equal to the quality factor threshold. Obtain the eigenfrequency, impedance, and impedance angle of each of the oscillators obtained in the previous step; Select one intrinsic frequency from multiple oscillators as the fundamental frequency, determine the measured deviation between the intrinsic frequencies of other oscillators and the fundamental frequency based on the fundamental frequency, and configure a preset deviation. Select the diaphragms obtained in the previous step whose measured deviation is less than or equal to the preset deviation.

4. The element selection method for a spherical multi-array focused ultrasound transducer according to claim 1, characterized in that, Measuring and obtaining the eigenfrequency, impedance, and impedance angle of the array elements in the pre-screened array group specifically includes the following steps: The frequency-impedance curve of each element in the pre-screened array group is obtained by using a frequency sweeping method. The array elements corresponding to frequency-impedance curves with multiple peaks or no peaks are removed, while the array elements corresponding to frequency-impedance curves with a single peak are retained. The intrinsic frequency, impedance, and impedance angle of the corresponding array element are obtained by measuring the frequency-impedance curve with a single peak value.

5. The element selection method for a spherical multi-array focused ultrasonic transducer according to claim 1, characterized in that, After obtaining multiple finely screened array elements, the array element screening method further includes: Multiple identical equivalent matrix elements are constructed. For each of these equivalent matrix elements, the construction method is as follows: Determine the number of array elements required in the equivalent array element set; At least one array element is selected from each of the finely screened array elements, and the total number of array elements selected from all the finely screened array elements is equal to the number of array elements required in the equivalent array element group; the equivalent array element group is composed of multiple array elements selected from the finely screened array elements corresponding to different intrinsic frequencies.

6. The element selection method for a spherical multi-array focused ultrasonic transducer according to claim 5, characterized in that, Each array element in the equivalent array group has the same intrinsic frequency components, the same termination equivalent impedance, and an impedance angle within a preset deviation range. The termination equivalent impedance is determined by the impedance of the array elements in the equivalent array element group and their connection relationship. That is, when the array elements in the equivalent array element group are connected in series, the equivalent impedance is the total series impedance of all array elements. When the array elements in the equivalent array element group are connected in parallel, the equivalent impedance is the total parallel impedance of all array elements. When the array elements in the equivalent array element group are mixed, the equivalent impedance is the total impedance of the mixed array elements.

7. The element selection method for a spherical multi-array focused ultrasound transducer according to claim 6, characterized in that, The total number of array elements in all the equivalent array elements is greater than or equal to 50.

8. The method for selecting array elements for a spherical multi-array focused ultrasonic transducer according to claim 1, characterized in that, The intrinsic frequency preset deviation is less than or equal to 50kHz.

9. The element selection method for a spherical multi-array focused ultrasound transducer according to claim 3, characterized in that, The quality factor threshold is greater than or equal to 500.

10. A spherical multi-array focused ultrasonic transducer element selection system, characterized in that, The array element selection system includes: The parameter configuration unit is used to configure the array element quality factor threshold, the intrinsic frequency preset deviation, and the impedance angle preset deviation. The pre-screening unit is used to obtain the measured value of the array element quality factor and remove the array elements whose measured value of the array element quality factor is less than the array element quality factor threshold, that is, to retain the array elements whose measured value of the array element quality factor is greater than or equal to the array element quality factor threshold, so as to output the pre-screened array element group. The fine screening unit is used to measure and obtain the eigenfrequency, impedance and impedance angle of the array element in the pre-screening array element group, and to combine at least two array elements with equal eigenfrequency into a fine screening array element group, and multiple eigenfrequency correspondences form multiple fine screening array element groups. The fine screening unit is used to select a fundamental frequency from multiple intrinsic frequencies and determine the measured deviations of other intrinsic frequencies from the fundamental frequency based on the fundamental frequency; select a fine screening array group from multiple fine screening array groups whose measured deviations are less than or equal to a preset deviation and whose number of array elements in the fine screening array group is greater than or equal to a preset number, so as to output multiple fine screening array groups.

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