Control method and system for acoustic radiation force of ultra-high frequency ultrasound

Abstract

Provided in the present invention are a control method and system for an acoustic radiation force of ultra-high frequency ultrasound. The method comprises: aligning an acoustic beam of ultra-high frequency ultrasound with an object under force; setting a carrier voltage of a pulse signal, such that an acoustic radiation force reaches a preset magnitude; adjusting a pulse width of the pulse signal; after adjusting the pulse width, determining whether the object under force meets a preset driving effect, and if so, ending the method; and if not, fine tuning the carrier voltage, and returning to adjusting the pulse width until the object under force meets the preset driving effect. In the technical solution of the present invention, a carrier voltage and a pulse width are adjusted on the basis of a preset driving effect of an object under force, such that the technical solution can be applicable to different driving effects and has a wide application range.

Description

Methods and systems for controlling acoustic radiation force of ultra-high frequency ultrasound Technical Field

[0001] This invention relates to the field of ultra-high frequency ultrasound technology, and in particular to a method and system for controlling the acoustic radiation force of ultra-high frequency ultrasound. Background Technology

[0002] Ultra-high frequency (UHF) ultrasound is generated by an UHF lithium niobate piezoelectric ceramic transducer excited by an excitation signal. Because the core component of the UHF transducer, the piezoelectric ceramic, is often only tens of micrometers in size and thickness, the energy of the excitation signal needs to be controlled to prevent breakdown of the piezoelectric ceramic. Typically, a sinusoidal signal as the carrier wave and a square wave as the modulating wave are used to excite the transducer. The frequency of the sinusoidal signal is the center frequency of the transducer. The energy of the excitation signal is controlled by modulating the amplitude of the sinusoidal signal, the frequency of the square wave, and the duty cycle. The resulting acoustic radiation force is also in square wave form, with the same duty cycle and frequency as the excitation signal. Technical issues

[0003] Currently, the application of acoustic radiation force of ultra-high frequency ultrasound is usually limited to a certain fixed excitation parameter. There is no concept of related control methods, and it will not be adjusted in real time during subsequent use, which cannot meet the needs of different driving effects and has a narrow range of applicable scenarios. Technical solutions

[0004] This invention provides a method and system for controlling the acoustic radiation force of ultra-high frequency ultrasound, in order to solve the problems of fixed excitation parameters and narrow applicable scenarios in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0006] According to a first aspect of the present invention, a method for controlling the acoustic radiation force of ultra-high frequency ultrasound is provided, comprising:

[0007] The sound beam of ultra-high frequency ultrasound is aimed at the object subjected to force;

[0008] Set the carrier voltage of the pulse signal to make the sound radiation force reach the preset level;

[0009] Adjust the pulse width of the pulse signal;

[0010] After adjusting the pulse width, determine whether the object under force meets the preset driving effect. If yes, the process ends; otherwise, fine-tune the carrier voltage and return to adjusting the pulse width until the object under force meets the preset driving effect.

[0011] Optionally, the setting of the carrier voltage of the pulse signal and the adjustment of the pulse width of the pulse signal further include:

[0012] Determine whether a continuous force-driven effect is required. If so, adjust the frequency of the pulse signal; otherwise, adjust the pulse width of the pulse signal.

[0013] Optionally, adjusting the frequency of the pulse signal specifically includes:

[0014] Analyze the equivalent dynamic model of the object under force to obtain the cutoff frequency of its frequency response curve;

[0015] The frequency of the pulse signal is obtained by using the cutoff frequency as the fundamental frequency of the pulse signal.

[0016] Optionally, if a continuous force driving effect is required, determining whether the object being driven by the force satisfies the preset driving effect further includes: determining whether the object being driven by the force satisfies the continuous force driving effect.

[0017] Optionally, determining whether the object subjected to force satisfies the continuous force driving effect specifically includes:

[0018] The displacement pattern of the probe is collected, and it is determined whether the displacement pattern is a continuous DC pattern. If it is, the continuous force driving effect is satisfied; otherwise, the continuous force driving effect is not satisfied.

[0019] According to a second aspect of the present invention, a high-frequency ultrasonic acoustic radiation force control system is provided, comprising:

[0020] The object subjected to force, which is used to sense the acoustic radiation force of ultra-high frequency ultrasound;

[0021] The carrier voltage setting module is used to set the carrier voltage of the pulse signal so that the acoustic radiation force reaches a preset level.

[0022] A pulse width adjustment module, used to adjust the pulse width of the pulse signal;

[0023] The driving effect confirmation module is used to determine whether the object under force meets the preset driving effect. If it does, the process ends; otherwise, the carrier voltage is finely adjusted and the process returns to the pulse width adjustment module until the object under force meets the preset driving effect.

[0024] Optional, also includes:

[0025] The continuous force drive confirmation module is used to determine whether a continuous force drive effect is needed. If so, it enters the adjustment of the frequency of the pulse signal; otherwise, it enters the pulse width adjustment module.

[0026] A frequency adjustment module is used to adjust the frequency of the pulse signal.

[0027] Optionally, the frequency adjustment module includes:

[0028] The equivalent dynamic model analysis module is used to analyze the equivalent dynamic model of the object under force and obtain the cutoff frequency of its frequency response curve.

[0029] A base frequency setting module is used to set the cutoff frequency as the base frequency of the pulse signal to obtain the frequency of the pulse signal.

[0030] Optionally, the driving effect confirmation module includes a vibration meter, which is used to acquire displacement information generated by the mechanical sensor due to the acoustic radiation force, so as to determine whether the object under force meets the preset driving effect based on the displacement information.

[0031] Optionally, the object subjected to force is an atomic force microscope probe. Beneficial effects

[0032] The ultrasonic radiation force control method and system provided by this invention adjusts the carrier voltage and pulse width according to the preset driving effect of the object being subjected to the force. It can control the acoustic radiation force according to different driving effects, meet the preset driving effect required by the object being subjected to the force, and has a wide range of applications.

[0033] Furthermore, the square-wave acoustic radiation force generated under fixed excitation parameters in existing technologies cannot meet the needs of certain driving scenarios requiring continuous force, thus limiting its applicability. An alternative solution of this invention further determines whether a continuous force driving effect is required. When a continuous force driving effect is needed, the frequency of the pulse signal is adjusted so that the sine and cosine components of the acoustic radiation force do not have an effect, while the free DC component does, manifesting as a continuous force. This results in the displacement of the object being driven being a continuous DC form, thus satisfying the requirement for a continuous force driving effect. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 is a flowchart of an ultra-high frequency ultrasonic acoustic radiation force control method according to an embodiment of the present invention;

[0036] Figure 2 is a schematic diagram of the pulse signal of ultra-high frequency ultrasound according to one embodiment of the present invention;

[0037] Figure 3 is a flowchart of a method for controlling the acoustic radiation force of ultra-high frequency ultrasound according to another embodiment of the present invention;

[0038] Figure 4 is a schematic diagram of the dynamic model of one embodiment of the present invention;

[0039] Figure 5 is a schematic diagram of the frequency response curve of one embodiment of the present invention;

[0040] Figure 6 is a schematic diagram of the acoustic radiation force control system of ultra-high frequency ultrasound according to an embodiment of the present invention.

[0041] Figure 7 is a partial structural schematic diagram of the acoustic radiation force control system of ultra-high frequency ultrasound according to an embodiment of the present invention.

[0042] Explanation of reference numerals in the attached figures:

[0043] 11-Ultra-high frequency ultrasonic transducer;

[0044] 21-The object subjected to force;

[0045] 22-Carrier voltage setting module;

[0046] 23 - Pulse width adjustment module;

[0047] 24-Drive effect confirmation module;

[0048] 25 - Continuous force drive confirmation module;

[0049] 26 - Frequency adjustment module;

[0050] 261 - Equivalent Dynamics Model Analysis Module;

[0051] 262-Baseband setting module. Embodiments of the present invention

[0052] 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.

[0053] In the description of this invention, it should be understood that the terms "upper part", "lower part", "upper end", "lower end", "lower surface", "upper surface", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention.

[0054] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0055] In the description of this invention, "a plurality of" means multiple, such as two, three, four, etc., unless otherwise explicitly specified.

[0056] In the description of this invention, unless otherwise explicitly specified and limited, the term "connection" and other such terms should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection, an electrical connection, or a connection that allows communication between the components; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0057] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0058] As mentioned in the background technology above: In existing applications of ultra-high frequency ultrasound acoustic radiation force, the usual practice is to first try excitation signals with different parameters. If the object being manipulated is controlled, the excitation signal is usually set to this fixed value in subsequent use, and no more real-time adjustment is made. Furthermore, it is unclear which parameter should be adjusted and the resulting impact is also unclear.

[0059] This invention utilizes a Fourier transform of the square-wave acoustic radiation force to determine its components, which can be categorized into several sine waves, several cosine waves, and a DC component. The sine and cosine waves have the same frequency and are proportional to the frequency of the acoustic radiation force. Analysis and verification reveal that by appropriately adjusting the carrier voltage and pulse width, the intensity of the acoustic radiation force can be controlled to achieve a preset intensity, thereby enabling the object subjected to the force to meet a preset driving effect. Furthermore, by appropriately setting the pulse frequency, the square-wave acoustic radiation force can produce a DC force effect, thus enabling the object subjected to the force to meet a continuous force driving effect.

[0060] Furthermore, verification revealed that the carrier voltage has a quadratic relationship with the magnitude of acoustic radiation force, while the pulse width has a linear relationship with the magnitude of acoustic radiation force.

[0061] In one embodiment, a method for controlling the acoustic radiation force of ultra-high frequency ultrasound is provided, as shown in Figure 1, which includes:

[0062] S11: Aim the ultra-high frequency ultrasonic beam at the object being subjected to force.

[0063] That is, to ensure that the object subjected to the force is within the range of the acoustic radiation force of ultra-high frequency ultrasound.

[0064] S12: Set the carrier voltage of the pulse signal so that the acoustic radiation force reaches the preset level.

[0065] By setting the carrier voltage, the sound radiation force can be made to reach a preset level. The carrier voltage can significantly adjust the magnitude of the sound radiation force, which is equivalent to coarse adjustment.

[0066] S13: Adjust the pulse width of the pulse signal so that the magnitude of the acoustic radiation force reaches the magnitude of the force required by the object to achieve the preset driving effect.

[0067] Please refer to Figure 2, which illustrates the pulse width of the pulse signal. By adjusting the pulse width, the magnitude of the sound radiation force can be made to reach a preset size, or a preset range, which means that the object being subjected to the force meets the preset driving effect. The adjustment of the pulse width to the magnitude of the sound radiation force is small and precise, equivalent to fine-tuning.

[0068] As an example, assuming the required acoustic radiation force is 10.01, it can be adjusted to 10 by setting the carrier voltage and then to 10.01 by adjusting the pulse width.

[0069] The pulse width is adjusted according to the required speed and / or displacement of the object being subjected to force; if the object needs to move faster and / or have a larger displacement, the pulse width can be adjusted to be larger.

[0070] Adjusting the pulse width allows for the control of acoustic radiation from the nanoNewton level to the microNewton level, while maintaining a resolution of hundreds of piconet.

[0071] S14: After adjusting the pulse width, determine whether the object under force meets the preset driving effect. If so, end the process; otherwise, fine-tune the carrier voltage and return to S13 to adjust the pulse width until the object under force meets the preset driving effect.

[0072] If the preset driving effect cannot be met by precisely adjusting the pulse width at the current sound radiation force level (i.e., at the set carrier voltage), the carrier voltage can be finely adjusted to a new level, and the pulse width can be precisely adjusted again at that level. This process is repeated until the object being driven meets the preset driving effect.

[0073] In one embodiment, referring to Figure 3, the step S12 setting of the carrier voltage of the pulse signal and S13 adjusting the pulse width of the pulse signal further includes:

[0074] S21: Determine whether a continuous force-driven effect is required. If so, proceed to S22 to adjust the frequency of the pulse signal; otherwise, proceed to S13 to adjust the pulse width of the pulse signal.

[0075] S22: Adjust the frequency of the pulse signal to make the sound radiation force produce a DC effect, so that the object being subjected to the force satisfies the effect of continuous force driving.

[0076] Referring to Figure 2, which also illustrates the frequency of the pulse signal, the form of action of the sound radiation force can be changed by adjusting the frequency of the pulse signal. Setting an appropriate frequency can make the sound radiation force produce a DC effect, which acts on the object and makes the object satisfy the continuous force driving effect.

[0077] Adjusting the pulse frequency allows for the control of acoustic radiation from a frequency range of 1 kHz to several hundred kHz.

[0078] In one embodiment, referring to Figure 3, S22 adjusts the frequency of the pulse signal, specifically including:

[0079] S221: Analyze the equivalent dynamic model of the object under force to obtain the cutoff frequency of its frequency response curve.

[0080] As an example, suppose the object subjected to force is a probe, and its equivalent dynamic model is a spring-damped model. Due to the existence of damping, its ability to respond to high-frequency forces is limited. Its frequency response curves are shown in Figures 4 and 5. Under the same external force amplitude, as the force frequency increases, the displacement it produces decreases. The frequency at which it decreases to -3dB is called the cutoff frequency.

[0081] It should be noted that the above embodiments use the spring-damped model as an example. In different embodiments, other equivalent dynamic models will also have similar frequency response curves and corresponding cutoff frequencies.

[0082] S222: The frequency of the pulse signal is obtained by using the cutoff frequency as the fundamental frequency of the pulse signal.

[0083] When the pulse frequency is large enough to exceed the frequency response range of the object being subjected to the force, the sine and cosine components of the pulsed acoustic radiation force do not have an effect; only the DC component has an effect, manifesting as a continuous force.

[0084] In one embodiment, if a continuous force driving effect is required, S14 further includes determining whether the object being driven satisfies the preset driving effect: determining whether the object being driven satisfies the continuous force driving effect.

[0085] In one embodiment, determining whether the object subjected to force satisfies the continuous force driving effect specifically includes:

[0086] Collect the displacement pattern of the object under force and determine whether its displacement pattern is a continuous DC pattern. If it is, the continuous force driving effect is satisfied; otherwise, the continuous force driving effect is not satisfied.

[0087] In one embodiment, an acoustic radiation force control system for ultra-high frequency ultrasound is also provided, as shown in Figures 6 and 7, which includes:

[0088] The object 21 is used to sense the acoustic radiation force of ultra-high frequency ultrasound; it is placed within the acoustic radiation force range of the ultra-high frequency ultrasound transducer 11.

[0089] The carrier voltage setting module 22 is used to set the carrier voltage of the pulse signal so that the acoustic radiation force reaches a preset level, which is equivalent to coarsely adjusting the magnitude of the acoustic radiation force.

[0090] The pulse width adjustment module 23 is used to adjust the pulse width of the pulse signal so that the object under force meets the preset driving effect, which is equivalent to fine-tuning the magnitude of the radiation force.

[0091] The driving effect confirmation module 24 is used to determine whether the object under force meets the preset driving effect. If it does, the process ends; otherwise, the carrier voltage is finely adjusted and the process returns to the pulse width adjustment module until the object under force meets the preset driving effect.

[0092] In one embodiment, the acoustic radiation force control system for ultra-high frequency ultrasound further includes:

[0093] The continuous force drive confirmation module 25 is used to determine whether a continuous force drive effect is needed. If so, it enters the frequency adjustment of the pulse signal; otherwise, it enters the pulse width adjustment module.

[0094] Frequency adjustment module 26 is used to adjust the frequency of the pulse signal.

[0095] In one embodiment, the continued reference graph frequency adjustment module 26 includes:

[0096] The equivalent dynamic model analysis module is used to analyze the equivalent dynamic model of a stressed object and obtain the cutoff frequency of its frequency response curve.

[0097] The base frequency setting module is used to set the cutoff frequency as the base frequency of the pulse signal to obtain the frequency of the pulse signal.

[0098] As an example, the drive effect confirmation module includes a vibration meter, which is used to acquire displacement information of the object under force due to the action of acoustic radiation force, so as to determine whether the object under force meets the preset drive effect based on the displacement information.

[0099] Preferably, the vibration meter can be a Doppler laser vibration meter.

[0100] As an example, the object subjected to the force is an atomic force microscope probe.

[0101] In the description of this specification, the references to terms such as "an embodiment," "an example," "a specific implementation process," and "an example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling the acoustic radiation force of ultra-high frequency ultrasound, characterized in that, include: The sound beam of ultra-high frequency ultrasound is aimed at the object subjected to force; Set the carrier voltage of the pulse signal to make the sound radiation force reach the preset level; Adjust the pulse width of the pulse signal; After adjusting the pulse width, determine whether the object under force meets the preset driving effect. If yes, the process ends; otherwise, fine-tune the carrier voltage and return to adjusting the pulse width until the object under force meets the preset driving effect.

2. The method for controlling the acoustic radiation force of ultra-high frequency ultrasound according to claim 1, characterized in that, The setting of the carrier voltage of the pulse signal and the adjustment of the pulse width of the pulse signal further include: Determine whether a continuous force-driven effect is required. If so, adjust the frequency of the pulse signal; otherwise, adjust the pulse width of the pulse signal.

3. The method for controlling the acoustic radiation force of ultra-high frequency ultrasound according to claim 2, characterized in that, Adjusting the frequency of the pulse signal specifically includes: Analyze the equivalent dynamic model of the object under force to obtain the cutoff frequency of its frequency response curve; The frequency of the pulse signal is obtained by using the cutoff frequency as the fundamental frequency of the pulse signal.

4. The method for controlling the acoustic radiation force of ultra-high frequency ultrasound according to claim 2, characterized in that, If a continuous force driving effect is required, determining whether the object being driven by the force satisfies the preset driving effect further includes: determining whether the object being driven by the force satisfies the continuous force driving effect.

5. The method for controlling the acoustic radiation force of ultra-high frequency ultrasound according to claim 4, characterized in that, The determination of whether the object subjected to force satisfies the continuous force driving effect specifically includes: The displacement pattern of the probe is collected, and it is determined whether the displacement pattern is a continuous DC pattern. If it is, the continuous force driving effect is satisfied; otherwise, the continuous force driving effect is not satisfied.

6. A control system for acoustic radiation force of ultra-high frequency ultrasound, characterized in that, include: The object subjected to force, which is used to sense the acoustic radiation force of ultra-high frequency ultrasound; The carrier voltage setting module is used to set the carrier voltage of the pulse signal so that the acoustic radiation force reaches a preset level. A pulse width adjustment module, used to adjust the pulse width of the pulse signal; The driving effect confirmation module is used to determine whether the object under force meets the preset driving effect. If it does, the process ends; otherwise, the carrier voltage is finely adjusted and the process returns to the pulse width adjustment module until the object under force meets the preset driving effect.

7. The acoustic radiation force control system for ultra-high frequency ultrasound according to claim 6, characterized in that, Also includes: The continuous force drive confirmation module is used to determine whether a continuous force drive effect is needed. If so, it enters the adjustment of the frequency of the pulse signal; otherwise, it enters the pulse width adjustment module. A frequency adjustment module is used to adjust the frequency of the pulse signal.

8. The acoustic radiation force control system for ultra-high frequency ultrasound according to claim 8, characterized in that, The frequency adjustment module includes: The equivalent dynamic model analysis module is used to analyze the equivalent dynamic model of the object under force and obtain the cutoff frequency of its frequency response curve. A base frequency setting module is used to set the cutoff frequency as the base frequency of the pulse signal to obtain the frequency of the pulse signal.

9. The acoustic radiation force control system for ultra-high frequency ultrasound according to any one of claims 6 to 8, characterized in that, The driving effect confirmation module includes a vibration meter, which is used to acquire displacement information generated by the mechanical sensor due to the acoustic radiation force, so as to determine whether the object under force meets the preset driving effect based on the displacement information.

10. The acoustic radiation force control system for ultra-high frequency ultrasound according to any one of claims 6 to 8, characterized in that, The object subjected to the force is an atomic force microscope probe.

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