A beam control method, system, electronic device, and readable storage medium for flexible ultrasonic devices

Abstract

This invention belongs to the field of flexible ultrasound technology and discloses a beam control method, system, electronic device, and readable storage medium for flexible ultrasound devices. Based on an arrayed flexible medical device, the curvature of each sub-piezoelectric ceramic in the array is calculated within a region. Based on the curvature of each sub-piezoelectric ceramic in the region, a delay channel acquisition strategy for each sub-piezoelectric ceramic is determined. Based on the delay channel of each sub-piezoelectric ceramic, after each ultrasound signal channel is delayed and focused on the area to be detected in the object, and before merging the channels, the optimal imaging effect is calculated. This invention aims to make ultrasound more focused on the detected area, eliminate artifacts as much as possible at the acquisition level, and improve the imaging quality of flexible piezoelectric transducers.

Description

Technical Field

[0001] This invention belongs to the field of flexible ultrasound technology, and particularly relates to a beam control method, system, electronic device, and readable storage medium for use in flexible ultrasound devices. Background Technology

[0002] Delay-and-sum (DAS) and minimum variance (MV) beamforming control strategies are commonly used in traditional rigid probe medical ultrasound imaging. These strategies work by directing or focusing the ultrasound transducer onto a signal from a specific point (often called the focal point), improving the contrast, spatial resolution, and signal-to-noise ratio of ultrasound images. However, this method has limitations, being only applicable to traditional rigid ultrasound probes. Flexible medical devices, with their attachable and wearable nature and ease of long-term monitoring, are increasingly becoming a focus of research and development. For arrayed flexible ultrasound devices, the spatial distribution of the sound beam depends on its curved shape. Curvature, as a key input to flexible ultrasound medical imaging systems, must be incorporated into the beam-focusing control strategy. Significantly improved image quality leads to potential increases in contrast and resolution for medical images from flexible devices.

[0003] like Figure 1 As shown, the time-delay superposition beamforming method is used independently of echo data, but its main lobe width is too wide and the side lobe response level is too high, resulting in defects in resolution and contrast. The minimum variance beamforming technique calculates dynamic weighting values ​​based on echo data, fully utilizing the characteristics of the echo signal and reducing side lobe signals. Its basic principle is to minimize the array output by keeping the gain constant in the desired direction, thereby improving image resolution. Compared to synchronous excitation of all piezoelectric ceramics, it is more suitable for curved surfaces such as those resembling the human body. Figure 2 The asynchronous incentive strategy is shown.

[0004] The method is based on the minimum variance method and also incorporates the curvature of the array devices as a key independent variable. The beam control strategy, with the added independent variable, suppresses interference signals from off-axis directions and does not allow large side waves in directions where no energy is received. The final achievable results are as follows: Figure 3 After each sound emission from the flexible ultrasonic array, the optimal weight for spatial measurement with imaging is calculated using the above method. By asynchronous sound emission, the ultrasound is more focused on the detected area, and artifacts are eliminated as much as possible at the acquisition level, thereby improving the imaging quality of the flexible piezoelectric transducer. Summary of the Invention

[0005] This invention provides a beam control method for flexible ultrasonic devices, which enables ultrasound to be more focused on the detected area, eliminates artifacts as much as possible at the acquisition level, and improves the imaging quality of flexible piezoelectric transducers.

[0006] This invention is achieved through the following technical solution:

[0007] A beam control method for flexible ultrasonic devices, the beam control method specifically includes,

[0008] Based on arrayed flexible medical devices, the curvature of each sub-piezoelectric ceramic on the array is calculated in the region;

[0009] The delay channel of each sub-piezoelectric ceramic is determined based on the curvature of each sub-piezoelectric ceramic in the region;

[0010] Based on the delay channel of each sub-piezoelectric ceramic, the optimal imaging effect is calculated after each ultrasonic signal channel is delayed and focused on the area to be detected in the object, and before the channels are merged.

[0011] A beam control method for flexible ultrasound devices, wherein the arraying of flexible medical devices specifically refers to the arraying of flexible medical devices as flexible transducers, wherein one piezoelectric ceramic of the flexible transducer is composed of M sub-piezoelectric ceramics.

[0012] A beam control method for flexible ultrasonic devices, wherein the curvature of each piezoelectric ceramic in the calculated array is specifically such that M piezoelectric ceramics record a signal R. m (t), then the curvature of each piezoelectric ceramic in the region is Z. m .

[0013] A beam control method for flexible ultrasonic devices, wherein determining the delay channel of each sub-piezoelectric ceramic specifically involves distributing N+1 scatterers in the probed space, wherein each scatterer reflects a signal S. p (t); Assume that only the S0(t) receiver is the focusing point, while other reflectors are interference sources;

[0014] d m，p δ(t) is the distance from reflector p to sensor m, and δ(t) is the pulse excitation function-Dirac function. It is the delay of sensor m, N m (t) is the noise of the m-th piezoelectric ceramic signal channel, and * is the convolution operator;

[0015] The m-th delay channel is described as:

[0016]

[0017] A beam control method for flexible ultrasonic devices, wherein the optimal imaging effect is calculated after each ultrasonic signal channel is delayed and focused at a point in the image and before merging the channels, specifically, the weighted sum B(t) of the spatial measurements of the imaging is calculated by the following expression; where ω is the weight of the m-th group of signals;

[0018]

[0019] Therefore, by solving the following conditions numerically, the optimal weights can be obtained, and this method can be used to control the delay timing of the flexible arrayed piezoelectric device:

[0020]

[0021] A beam control system for flexible ultrasonic devices, the system comprising:

[0022] The acquisition module is used to acquire the signal R from each piezoelectric ceramic of the arrayed flexible medical device. m (t);

[0023] The calculation module is used to calculate the curvature of each sub-piezoelectric ceramic in the region and determine the delay channel of each sub-piezoelectric ceramic;

[0024] The calculation module is also used to calculate the optimal imaging effect before merging channels.

[0025] A beam control system for flexible ultrasound devices, wherein the arrayed flexible medical device is a flexible transducer, and one piezoelectric ceramic of the flexible transducer is composed of M sub-piezoelectric ceramics.

[0026] A beam control system for flexible ultrasonic devices, wherein the computing module specifically comprises M piezoelectric ceramics recording a signal R. m (t), then the curvature of each piezoelectric ceramic in the region is Z. m ;

[0027] N+1 scatterers are distributed within the probed space, and each scatterer reflects the signal S. p (t); Assume that only the S0(t) receiver is the focusing point, while other reflectors are interference sources;

[0028] d m，p δ(t) is the distance from reflector p to sensor m, and δ(t) is the pulse excitation function-Dirac function. It is the delay of sensor m, N m (t) is the noise of the m-th piezoelectric ceramic signal channel, and * is the convolution operator;

[0029] The m-th delay channel is described as:

[0030]

[0031] The weighted sum B(t) of the spatial measurements of the image will be calculated by the following expression; where ω is the weight of the m-th group of signals;

[0032]

[0033] Therefore, we only need to solve the following conditions using numerical methods to obtain the optimal weights:

[0034]

[0035] An electronic device includes: a processor and a memory storing computer program instructions.

[0036] The processor reads and executes the computer program instructions to implement the above method steps.

[0037] A readable storage medium storing computer program instructions that, when executed by a processor, implement the above-described method steps.

[0038] The beneficial effects of this invention are:

[0039] This invention also considers the curvature of the array device as a key independent variable. The beam control strategy with this added independent variable suppresses interference signals from off-axis directions and does not allow large side waves to occur in directions where no energy is received.

[0040] This invention gradually reduces imaging errors; it eliminates artifacts as much as possible at the acquisition level, thereby improving the imaging quality of flexible piezoelectric transducers. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the traditional control strategy of time-delay superposition.

[0042] Figure 2 This is a comparative diagram of the minimum variance method of the present invention.

[0043] Figure 3 These are schematic diagrams of asynchronous control of excitation time in this invention: (a) schematic diagram of synchronous sound generation, and (b) schematic diagram of asynchronous sound generation.

[0044] Figure 4 These are the target diagrams of the present invention, wherein (a) is a target schematic diagram, (b) is a target error schematic diagram of the existing method, and (c) is a target error schematic diagram of the present invention.

[0045] Figure 5This is a schematic diagram of the simulation effect (inverted color processing) of the present invention, wherein (a) is the simulation effect of the traditional control strategy, and (b) is the simulation effect of the present invention. Detailed Implementation

[0046] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0048] A beam control method for flexible ultrasonic devices, the beam control method specifically includes,

[0049] Arraying flexible medical devices;

[0050] Based on arrayed flexible medical devices, the curvature of each sub-piezoelectric ceramic on the array is calculated in the region;

[0051] The delay channel of each sub-piezoelectric ceramic is determined based on the curvature of each sub-piezoelectric ceramic in the region;

[0052] Based on the delay channel of each sub-piezoelectric ceramic, the optimal imaging effect is calculated after each ultrasonic signal channel is delayed and focused on the area to be detected in the object, and before the channels are merged.

[0053] After the flexible sensor deforms, the merging channel controls the transmission timing and logic, and combines this method to eliminate artifacts as much as possible at the acquisition level, thereby improving the imaging quality of the flexible piezoelectric transducer.

[0054] A beam control method for flexible ultrasound devices, wherein the arraying of flexible medical devices specifically refers to the arraying of flexible medical devices as flexible transducers, wherein one piezoelectric ceramic of the flexible transducer is composed of M sub-piezoelectric ceramics.

[0055] A beam control method for flexible ultrasonic devices, wherein the curvature of each piezoelectric ceramic in the calculated array is specifically such that M piezoelectric ceramics record a signal R. m (t), then the curvature of each piezoelectric ceramic in the region is Z. m .

[0056] A beam control method for flexible ultrasonic devices, wherein determining the delay channel of each sub-piezoelectric ceramic specifically involves distributing N+1 scatterers in the probed space, wherein each scatterer reflects a signal S. p (t); Assume that only the S0(t) receiver is the focusing point, while other reflectors are interference sources;

[0057] d m，p δ(t) is the distance from reflector p to sensor m, and δ(t) is the pulse excitation function-Dirac function. It is the delay of sensor m, N m (t) is the noise of the m-th piezoelectric ceramic signal channel, and * is the convolution operator;

[0058] The m-th delay channel is described as:

[0059]

[0060] A beam control method for flexible ultrasonic devices, wherein the optimal imaging effect is calculated after each ultrasonic signal channel is delayed and focused at a point in the image and before merging the channels, specifically, the weighted sum B(t) of the spatial measurements of the imaging is calculated by the following expression; where ω is the weight of the m-th group of signals;

[0061]

[0062] Therefore, by solving the following conditions numerically, the optimal weights can be obtained, and this method can be used to control the delay timing of the flexible arrayed piezoelectric device:

[0063]

[0064] like Figure 4As shown in the figure, the sound pressure level of the sound field generated by a 64 piezoelectric ceramic array with a center frequency of 7.5MHz under a given curvature condition is compared with the focusing effect on the non-central axis achieved by the present invention at the same time. It can be seen that in the traditional ultrasonic algorithm, the region with high intensity of the focused spot is relatively dispersed, which is a major drawback for time-constrained ultrasonic imaging systems. The reverberation generated by the side petal bundles will greatly interfere with the imaging results. In contrast, the sound pressure level pattern of the sound field generated by the present solution shows that the region with high intensity of the focused spot in the focusing area is relatively concentrated. Therefore, the present method is beneficial to improving the contrast, spatial resolution and other performance parameters of the ultrasonic image.

[0065] A beam control system for flexible ultrasonic devices, the system comprising:

[0066] The acquisition module is used to acquire the signal R from each piezoelectric ceramic of the arrayed flexible medical device. m (t);

[0067] The calculation module is used to calculate the curvature of each sub-piezoelectric ceramic in the region and determine the delay channel of each sub-piezoelectric ceramic;

[0068] The calculation module is also used to calculate the optimal imaging effect before merging channels.

[0069] A beam control system for flexible ultrasound devices, wherein the arrayed flexible medical device is a flexible transducer, and one piezoelectric ceramic of the flexible transducer is composed of M sub-piezoelectric ceramics.

[0070] A beam control system for flexible ultrasonic devices, wherein the computing module specifically comprises M piezoelectric ceramics recording a signal R. m (t), then the curvature of each piezoelectric ceramic in the region is Z. m ;

[0071] N+1 scatterers are distributed within the probed space, and each scatterer reflects the signal S. p (t); Assume that only the S0(t) receiver is the focusing point, while other reflectors are interference sources;

[0072] d m，p δ(t) is the distance from reflector p to sensor m, and δ(t) is the pulse excitation function-Dirac function. It is the delay of sensor m, N m (t) is the noise of the m-th piezoelectric ceramic signal channel, and * is the convolution operator;

[0073] The m-th delay channel is described as:

[0074]

[0075] The weighted sum B(t) of the spatial measurements of the image will be calculated by the following expression; where ω is the weight of the m-th group of signals;

[0076]

[0077] Therefore, we only need to solve the following conditions using numerical methods to obtain the optimal weights:

[0078]

[0079] Figure 4 The target diagram is shown in the figure. Taking a 1x4 array of flexible ultrasonic sensors to perform ultrasonic imaging on a spatial surface with different curvatures as an example, the flesh-colored area is the surrounding medium and the red area is the main area to be detected.

[0080] Figure 4 This method allows for a gradual reduction in imaging errors. By eliminating error artifacts at the acquisition level, the imaging quality of flexible piezoelectric transducers can be improved.

[0081] An electronic device includes: a processor and a memory storing computer program instructions.

[0082] The processor reads and executes the computer program instructions to implement the above method steps.

[0083] A readable storage medium storing computer program instructions that, when executed by a processor, implement the above-described method steps.

Claims

1. A beam control method for flexible ultrasonic devices, characterized in that, The beam control method specifically includes: Arraying flexible medical devices; Based on arrayed flexible medical devices, the curvature of each sub-piezoelectric ceramic on the array is calculated in the region; The delay channel of each sub-piezoelectric ceramic is determined based on the curvature of each sub-piezoelectric ceramic in the region; Based on the delay channel of each sub-piezoelectric ceramic, the optimal imaging effect is calculated after each ultrasonic signal channel is delayed and focused on the area to be detected in the object, and before the channels are merged. Specifically, the curvature of each sub-piezoelectric ceramic in the region is calculated by the M sub-piezoelectric ceramics recording one signal. The curvature of each sub-piezoelectric ceramic in the region is then... ; Specifically, determining the delay channel for each sub-piezoelectric ceramic involves distributing N+1 scatterers within the probed space, where each scatterer reflects a signal. ; Assuming only It is the focal point of the receiver, while other reflectors are sources of interference; δ(t) is the distance from the reflector p to the piezoelectric ceramic m, and δ(t) is the pulse excitation function - Dirac function. It is the delay of the piezoelectric ceramic m. is the noise of the m-th sub-piezoelectric ceramic signal channel, and * is the convolution operator; The m-th delay channel is described as follows: （1）。 2. The beam control method for flexible ultrasonic devices according to claim 1, characterized in that, Specifically, the arraying of the flexible medical device refers to a flexible transducer, wherein one piezoelectric ceramic of the flexible transducer is composed of M sub-piezoelectric ceramics.

3. The beam control method for flexible ultrasonic devices according to claim 1, characterized in that, The optimal imaging effect is calculated after each ultrasound signal channel is delayed and focused at a point in the image, and before merging the channels. Specifically, this involves a weighted sum of the spatial measurements of the imaging. It will be calculated by the following expression; where It represents the weight of the m-th group of signals; （2） Therefore, by solving the following conditions numerically, the optimal weights can be obtained, and this method can be used to control the delay timing of the flexible arrayed piezoelectric device: （3）。 4. A control system for a beam control method applied to flexible ultrasonic devices, characterized in that, The control system uses a beam control method for flexible ultrasonic devices as described in any one of claims 1-3, and the control system includes, The acquisition module is used to acquire signals from each piezoelectric ceramic in an array of flexible medical devices. ; The calculation module is used to calculate the curvature of each sub-piezoelectric ceramic in the region and determine the delay channel of each sub-piezoelectric ceramic; The calculation module is also used to calculate the optimal imaging effect before merging channels; Specifically, the calculation module involves M sub-piezoelectric ceramics recording one signal. The curvature of each sub-piezoelectric ceramic in the region is then... ; N+1 scatterers are distributed within the probed space, and each scatterer reflects a signal. ; Assuming only It is the focal point of the receiver, while other reflectors are sources of interference; δ(t) is the distance from the reflector p to the piezoelectric ceramic m, and δ(t) is the pulse excitation function - Dirac function. It is the delay of the piezoelectric ceramic m. is the noise of the m-th sub-piezoelectric ceramic signal channel, and * is the convolution operator; The m-th delay channel is described as follows: （1）； Weighted sum of spatial measurements of imaging It will be calculated by the following expression; where It represents the weight of the m-th group of signals; （2） Therefore, we only need to solve the following conditions using numerical methods to obtain the optimal weights: （3）。 5. The control system of the beam control method applied to a flexible ultrasonic device according to claim 4, characterized in that, The arrayed flexible medical device is a flexible transducer, and one piezoelectric ceramic of the flexible transducer is composed of M sub-piezoelectric ceramics.

6. An electronic device, characterized in that, The device includes: a processor, and a memory storing computer program instructions. The processor reads and executes the computer program instructions to implement the method steps as described in any one of claims 1-3.

7. A readable storage medium, characterized in that, The readable storage medium stores computer program instructions that, when executed by a processor, implement the steps of the method as described in any one of claims 1-3.

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