An ultrasonic microneedle system with adaptive depth of action

Abstract

This invention provides an adaptive depth-of-application ultrasonic microneedle system, belonging to the field of microneedling. The ultrasonic microneedle system includes: a microneedle assembly, a pressure detection assembly, an ultrasonic transmitter, and a microprocessor. The microneedle assembly is disposed on one side of the pressure detection assembly; the ultrasonic transmitter is disposed on the side opposite the pressure detection assembly and the microneedle assembly. During operation, the microneedle assembly contacts the target skin. The microprocessor applies a detection current to the pressure detection assembly and acquires the real-time voltage across the pressure detection assembly. Based on the real-time voltage across the pressure detection assembly, the detection current, and the user-selected insertion mode, it generates an ultrasonic driving signal. The ultrasonic transmitter generates ultrasonic sound pressure based on the ultrasonic driving signal, applying pressure to the microneedle assembly, causing the microneedle assembly to displace and reach the target point on the target skin. This invention can adaptively and continuously adjust the insertion depth of the microneedle, improving the accuracy of the microneedle's target point.

Description

Technical Field

[0001] This invention relates to the field of microneedles, and in particular to an ultrasonic microneedle system with adaptive depth of action. Background Technology

[0002] Microneedling is a common cosmetic procedure. The principle behind microneedling is to use a microneedling roller with many tiny needles to stimulate the skin. In a very short time, the microneedles can create millions of microchannels, allowing active ingredients to effectively penetrate the skin. At the same time, the microneedles stimulate the dermis, promoting collagen production through the skin's self-healing ability. This can increase the thickness of the epidermis by about 8%, and its effects are comparable to laser and filler-based cosmetic surgery.

[0003] However, in traditional microneedling cosmetic treatments, the needle insertion mode and depth need to be manually adjusted. The unevenness of the local skin makes it difficult to accurately control the target point, resulting in poor cosmetic effects. Summary of the Invention

[0004] The purpose of this invention is to provide an ultrasonic microneedle system with adaptive depth of action, which can improve the accuracy of the microneedle's target point.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] An adaptive depth-of-application ultrasonic microneedle system includes: a microneedle assembly, a pressure detection assembly, an ultrasonic transmitter, and a microprocessor;

[0007] The microneedle assembly is disposed on one side of the pressure detection assembly; the ultrasonic emitting device is disposed on the pressure detection assembly on the side opposite to the microneedle assembly; during operation, the microneedle assembly comes into contact with the target skin;

[0008] The microprocessor is connected to the pressure detection component and the ultrasonic transmitting device respectively; the microprocessor is used to apply a detection current to the pressure detection component and obtain the real-time voltage across the pressure detection component, and generate an ultrasonic driving signal based on the real-time voltage across the pressure detection component, the detection current and the needle insertion mode selected by the user.

[0009] The ultrasonic transmitting device is used to generate ultrasonic sound pressure according to the ultrasonic driving signal, apply pressure to the microneedle assembly, cause the microneedle assembly to move, and reach the target point of the target skin.

[0010] Optionally, the microneedle assembly includes multiple microneedles and multiple microneedle movable parts; each microneedle is fixed to the pressure detection assembly through a microneedle movable part.

[0011] Optionally, the microprocessor includes:

[0012] The pattern acquisition module is used to acquire the needle insertion pattern selected by the user.

[0013] A current application module, connected to the pressure detection component, is used to apply a detection current to the pressure detection component;

[0014] A voltage acquisition module, connected to the pressure detection component, is used to acquire the real-time voltage across the pressure detection component.

[0015] The resistance calculation module is connected to the current application module and the voltage acquisition module respectively, and is used to calculate the real-time resistance of the pressure detection component based on the real-time voltage of the pressure detection component and the detection current.

[0016] A pressure calculation module, connected to the resistance calculation module, is used to calculate the pressure value of the target skin at any given moment when the microneedle component contacts the target skin, based on the resistance value of the pressure detection component at the current moment and the initial resistance value; the initial resistance value is the resistance value of the pressure detection component when the microneedle component is not in contact with the target skin.

[0017] An intensity determination module, connected to the voltage acquisition module, is used to determine the ultrasonic signal intensity based on the real-time voltage across the pressure detection component.

[0018] A cycle determination module, connected to the pressure calculation module, is used to determine the needle insertion cycle based on the pressure value of the target skin.

[0019] An ultrasonic drive module is connected to the mode acquisition module, the intensity determination module, the period determination module, and the ultrasonic transmitting device, respectively, and is used to generate an ultrasonic drive signal based on the ultrasonic signal intensity, the needle insertion period, and the needle insertion mode selected by the user.

[0020] Optionally, the resistance calculation module uses formula R. t =U t / I t Calculate the resistance of the pressure sensing component at time t; where R t Let U be the resistance of the pressure sensing component at time t. t Let I be the voltage across the pressure sensing component at time t. t To detect current;

[0021] The pressure calculation module uses a formula. Calculate the pressure value of the target skin at time t; where P t Let t be the pressure value of the target skin, R0 be the initial resistance of the pressure detection component, and ε be the pre-determined pressure-resistance change coefficient of the pressure detection component.

[0022] Optionally, the needle insertion mode includes a sine wave needle insertion mode, a pulse needle insertion mode, and a sawtooth wave needle insertion mode.

[0023] Optionally, when the user selects a sinusoidal needle insertion mode, the ultrasonic drive signal generated by the microprocessor is:

[0024]

[0025] Where S(t) is the ultrasonic drive signal generated by the microprocessor at time t, E is the ultrasonic signal intensity, and T is the needle insertion period.

[0026] Optionally, when the user selects pulse needle insertion mode, the ultrasonic drive signal generated by the microprocessor is:

[0027] S(t) = E,

[0028] Where S(t) is the ultrasonic drive signal generated by the microprocessor at time t, E is the ultrasonic signal intensity, and T is the needle insertion period.

[0029] Optionally, when the user selects the sawtooth wave needle insertion mode, the ultrasonic drive signal generated by the microprocessor is:

[0030] S(t) = Et, 0 ≤ t ≤ T;

[0031] Where S(t) is the ultrasonic drive signal generated by the microprocessor at time t, E is the ultrasonic signal intensity, and T is the needle insertion period.

[0032] Optionally, the ultrasonic sound pressure generated by the ultrasonic transmitting device is:

[0033]

[0034] Where p is the ultrasonic sound pressure, ρ0 is the tissue density, c0 is the sound velocity, S(t) is the ultrasonic driving signal generated by the microprocessor at time t, and k w Let be the wave number and a be the radius of the sound field.

[0035] Optionally, the displacement generated by the microneedle assembly is:

[0036]

[0037] Where d is the displacement generated by the microneedle component, p is the ultrasonic pressure, a is the sound field radius, t' is the duration of action, and m is the mass of the microneedle component.

[0038] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0039] This invention combines the advantages of ultrasound and microneedles. Through the cooperation of a pressure detection component and a microprocessor, it can detect the pressure of the target skin in real time and generate different ultrasound driving signals according to the unevenness of the target skin. This enables adaptive and continuous adjustment of the microneedle insertion depth, thereby improving the accuracy of the microneedle target point. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments 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.

[0041] Figure 1 A schematic diagram of the adaptive depth-of-action ultrasonic microneedle system provided by the present invention;

[0042] Figure 2 A flowchart of the adaptive depth-of-action ultrasonic microneedle system provided by the present invention;

[0043] Figure 3 The graph shows the functional relationship between the voltage across the pressure detection component and the ultrasonic intensity.

[0044] Figure 4 This is a schematic diagram illustrating the relationship between ultrasound energy and target skin pressure.

[0045] Figure 5 A schematic diagram showing the working conditions and ultrasonic energy of an ultrasonic microneedle system at a relatively raised area of ​​skin;

[0046] Figure 6 This is a schematic diagram showing the working conditions and ultrasonic energy of an ultrasonic microneedle system in a relatively concave skin area.

[0047] Symbol explanation:

[0048] 1-Microprocessor, 2-Ultrasonic emission device, 3-Pressure detection component, 4-Microneedle, 5-Microneedle moving part. Detailed Implementation

[0049] 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.

[0050] Sound waves with frequencies higher than 20 kHz are called ultrasound. Ultrasound has good directionality and penetrating power. Ultrasound primarily utilizes the piezoelectric deformation physical property of transducers. An ultrasonic transducer is a ceramic crystal exhibiting the piezoelectric effect; that is, under the influence of an applied electric field, the crystal deforms along the direction of the electric field, thus producing displacement. The two main parameters of ultrasound are frequency (F ≥ 20000 Hz) and power density (p = transmitted power (W) / transmitted area (cm²)). 2 Typically, the power density p ≥ 0.3 W / cm². Ultrasonic transducers, by stimulating different amounts of ultrasonic energy, cause themselves to undergo radial displacement, thus transmitting strong energy while also physically altering the insertion depth of the implant. Furthermore, ultrasound exhibits reflection characteristics and can produce interference, superposition, and resonance phenomena. When propagating in a liquid medium, it can generate cavitation and strong impact at the interface, making it suitable for percutaneous transdermal therapy.

[0051] The purpose of this invention is to provide an adaptive depth-of-application ultrasonic microneedling system that combines the advantages of ultrasound and cosmetic microneedling. This system can adaptively adjust the depth of application of the microneedles according to the contours of the target skin to achieve the optimal treatment target. It also has the functions of microneedling, anti-aging, and penetration enhancement devices.

[0052] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0053] like Figure 1 As shown, the adaptive depth-of-application ultrasonic microneedle system provided by the present invention includes: a microneedle assembly, a pressure detection assembly 3, an ultrasonic transmitting device 2, and a microprocessor 1. In this embodiment, the pressure detection assembly 3 is a resistance strain gauge.

[0054] The microneedle assembly is disposed on one side of the pressure detection assembly 3. The ultrasonic emitting device 2 is disposed on the side of the pressure detection assembly 3 opposite to the microneedle assembly. During operation, the microneedle assembly comes into contact with the target skin.

[0055] Specifically, the microneedle assembly includes multiple microneedles 4 and multiple microneedle movable parts 5. Each microneedle 4 is fixed to the pressure detection assembly 3 via a microneedle movable part 5. The microneedle movable part 5 enables the microneedle 4 to move in the vertical direction. As a specific embodiment, the microneedle movable part 5 is a spring.

[0056] The microprocessor 1 is connected to the pressure detection component 3 and the ultrasonic transmitting device 2 respectively; the microprocessor 1 is used to apply a detection current to the pressure detection component 3 and obtain the real-time voltage at both ends of the pressure detection component 3, and generate an ultrasonic driving signal according to the real-time voltage at both ends of the pressure detection component 3, the detection current and the needle insertion mode selected by the user.

[0057] The ultrasonic transmitting device 2 is used to generate ultrasonic sound pressure according to the ultrasonic driving signal, apply pressure to the microneedle assembly, cause the microneedle assembly to move, and reach the target point of the target skin.

[0058] Specifically, the ultrasonic transmitting device 2 uses an ultrasonic piezoelectric transducer to generate ultrasonic voltage boost.

[0059] Furthermore, the microprocessor 1 includes: a mode acquisition module, a current application module, a voltage acquisition module, a resistance calculation module, a pressure calculation module, an intensity determination module, a period determination module, and an ultrasonic drive module.

[0060] The pattern acquisition module is used to obtain the needle insertion pattern selected by the user.

[0061] The current application module is connected to the pressure detection component 3, and the current application module is used to apply a detection current to the pressure detection component 3.

[0062] The voltage acquisition module is connected to the pressure detection component 3, and the voltage acquisition module is used to acquire the real-time voltage across the pressure detection component 3.

[0063] The resistance calculation module is connected to both the current application module and the voltage acquisition module. The resistance calculation module is used to calculate the real-time resistance of the pressure detection component 3 based on the real-time voltage of the pressure detection component 3 and the detection current. Specifically, the resistance calculation module uses formula R... t =U t / I t Calculate the resistance of pressure detection component 3 at time t; where R t Let U be the resistance value of pressure detection component 3 at time t. t Let I be the voltage across pressure sensing component 3 at time t. t To detect current.

[0064] The pressure calculation module is connected to the resistance calculation module. The pressure calculation module calculates the pressure value of the target skin at any given moment when the microneedle component contacts the target skin, based on the resistance value of the pressure detection component 3 at that moment and its initial resistance value. The initial resistance value is the resistance value of the pressure detection component 3 when the microneedle component is not in contact with the target skin. Specifically, the pressure calculation module uses the formula... Calculate the pressure value of the target skin at time t; where P t Let t be the pressure value of the target skin, R0 be the initial resistance of the pressure detection component, and ε be the pre-determined pressure-resistance change coefficient of the pressure detection component.

[0065] The intensity determination module is connected to the voltage acquisition module. The intensity determination module is used to determine the intensity of the ultrasonic signal based on the real-time voltage at both ends of the pressure detection component 3.

[0066] The cycle determination module is connected to the pressure calculation module, and the cycle determination module is used to determine the needle insertion cycle based on the pressure value of the target skin.

[0067] The ultrasonic drive module is connected to the mode acquisition module, the intensity determination module, the period determination module and the ultrasonic transmitting device 2 respectively. The ultrasonic drive module is used to generate an ultrasonic drive signal according to the ultrasonic signal intensity, the needle insertion period and the needle insertion mode selected by the user.

[0068] In this embodiment, the needle insertion modes include sine wave needle insertion mode, pulse needle insertion mode, and sawtooth wave needle insertion mode.

[0069] When the user selects the sine wave needle insertion mode, the ultrasonic drive signal generated by the microprocessor 1 is:

[0070] When the user selects pulse needle insertion mode, the ultrasonic drive signal generated by the microprocessor 1 is: S(t) = E,

[0071] When the user selects the sawtooth wave needle insertion mode, the ultrasonic drive signal generated by the microprocessor 1 is: S(t)=Et,0≤t≤T.

[0072] Where S(t) is the ultrasonic drive signal generated by the microprocessor at time t, E is the ultrasonic signal intensity, and T is the needle insertion period.

[0073] Furthermore, the ultrasonic sound pressure generated by the ultrasonic transmitting device 2 is:

[0074]

[0075] Where p is the ultrasonic sound pressure, ρ0 is the tissue density, c0 is the sound velocity, S(t) is the ultrasonic driving signal generated by microprocessor 1 at time t, and k w Let be the wave number and a be the radius of the sound field.

[0076] The displacement generated by the microneedle assembly is:

[0077]

[0078] Where d is the displacement generated by the microneedle component, p is the ultrasonic pressure, a is the sound field radius, t' is the duration of action, and m is the mass of the microneedle component.

[0079] The adaptive depth-of-application ultrasonic microneedle system provided by this invention can be applied to existing beauty devices for cosmetic treatments on target skin.

[0080] Because the insertion depth of the microneedle 4 differs in areas of concave and convex skin, the pressure detected by the pressure detection component 3 also differs. This invention combines the advantages of ultrasound and cosmetic microneedling, enabling the device using this system to adaptively and continuously adjust the vibration power of the ultrasonic piezoelectric transducer according to the unevenness of the target skin during cosmetic procedures. This ensures that the depth of ultrasound application is not inconsistent due to the unevenness of the skin, thus preventing the failure to achieve the best cosmetic effect. By adaptively and continuously adjusting the ultrasonic signal and energy, the insertion mode and depth of action are controlled to match the optimal treatment target. Ultrasound and microneedles 4 also promote each other's effects, especially in the clinical superposition effect of anti-aging, which promotes the absorption of effective ingredients by the target skin.

[0081] To better understand the technical solution of the present invention, the following is in conjunction with... Figure 2 This invention describes the working process of the adaptive depth ultrasonic microneedle system.

[0082] Step 1: Start the ultrasonic microneedle system and manually set the needle insertion mode.

[0083] Step 2: Signal initialization of pressure detection component 3: When the ultrasonic microneedle system is powered on and the microneedle 4 is not in contact with the target skin, the microprocessor 1 applies a detection current I to the pressure detection component 3. t Record the voltage U0 across the resistance strain gauge of pressure detection component 3, and calculate the initial resistance value R0 of the resistance strain gauge based on U0: R0 = U0 / I t .

[0084] Step 3: Initialization of ultrasonic transmitter 2: Waiting for transmission parameter input.

[0085] Step 4: After the microneedle 4 contacts the target skin, the voltage U0 across the resistance strain gauge changes to U. t According to U t Calculate the current resistance R of the resistance strain gauge connected to microneedle 4. t And according to R t Calculate the pressure value P from the target skin t .

[0086] Step 5: Based on the detected voltage U across the resistance strain gauge t And, based on a pre-established functional relationship between the voltage across the strain gauge and the ultrasonic signal intensity, the ultrasonic signal intensity is dynamically set. For example... Figure 3 The figure shows the functional relationship between ultrasonic signal intensity and the voltage across the resistance strain gauge.

[0087] Step 6: Based on the detected pressure value P from the target skin t Calculate the needle insertion cycle T: T = kP t Where k is the linear relationship coefficient between pressure and needle insertion cycle; the higher the pressure, the longer the needle insertion cycle, and vice versa. For example... Figure 4 The diagram shows the relationship between ultrasound intensity and target skin pressure.

[0088] Step 7: The ultrasonic transmitting device 2 generates an ultrasonic driving signal based on the needle insertion mode selected in step 1, the ultrasonic signal intensity calculated in step 5, and the needle insertion cycle calculated in step 6.

[0089] Step 8: An ultrasonic driving signal is applied to the ultrasonic piezoelectric transducer to generate ultrasonic pressure p for a single needle insertion.

[0090] Step 9: Because the ultrasonic piezoelectric transducer is connected to the microneedle 4, the ultrasonic pressure applies pressure to the microneedle 4, causing the microneedle 4 to undergo a thickness displacement d, accurately reaching the target point. For example... Figure 5 As shown, at more raised areas of skin, the generated ultrasonic energy is lower, the compression of the microneedle moving part 5 is greater, and the pressure on the pressure detection component 3 is higher. Figure 6 As shown, in more concave areas of skin, the generated ultrasonic energy is greater, the compression of the microneedle moving part 5 is smaller, and the pressure on the pressure detection component 3 is smaller.

[0091] Step 10: Change the treatment site and repeat steps 4 through 9.

[0092] In facial aesthetic procedures, when the skin is raised, the microneedle 4 experiences greater pressure, and the microprocessor 1 controls the application of a lower ultrasound intensity, resulting in a shallower depth of action for the microneedle 4. Conversely, when the skin is depressed, the microneedle 4 experiences less pressure, and the microprocessor 1 controls the application of a higher ultrasound intensity, resulting in a deeper depth of action for the microneedle 4. This invention calculates the emitted energy of the ultrasound waves and controls the ultrasound boost of the ultrasonic piezoelectric transducer. Simultaneously, the insertion mode of the microneedle 4 is variable, allowing the depth of action of the microneedle 4 into the target skin to be adaptively and continuously adjustable, and to accurately reach the target point.

[0093] In summary, the adaptive depth-of-action ultrasonic microneedle system provided by this invention is an automated device with high integration, easy portability, simple operation, safety and reliability, and low cost, meeting the requirements for home use, and can achieve diverse functions (penetration promotion, anti-aging, lifting, etc.).

[0094] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An adaptive depth-of-application ultrasonic microneedle system, characterized in that, The adaptive depth-of-application ultrasonic microneedle system includes: a microneedle assembly, a pressure detection assembly, an ultrasonic transmitting device, and a microprocessor; the pressure detection assembly is a resistance strain gauge. The microneedle assembly is disposed on one side of the pressure detection assembly; the ultrasonic emitting device is disposed on the pressure detection assembly on the side opposite to the microneedle assembly; during operation, the microneedle assembly comes into contact with the target skin; The microprocessor is connected to the pressure detection component and the ultrasonic transmitting device respectively; the microprocessor is used to apply a detection current to the pressure detection component and obtain the real-time voltage across the pressure detection component, and generate an ultrasonic driving signal based on the real-time voltage across the pressure detection component, the detection current and the needle insertion mode selected by the user. The ultrasonic transmitting device is used to generate ultrasonic sound pressure according to the ultrasonic driving signal, apply pressure to the microneedle assembly, and cause the microneedle assembly to move to the target point of the target skin. The microprocessor includes: The pattern acquisition module is used to acquire the needle insertion pattern selected by the user. A current application module, connected to the pressure detection component, is used to apply a detection current to the pressure detection component; A voltage acquisition module, connected to the pressure detection component, is used to acquire the real-time voltage across the pressure detection component. The resistance calculation module, connected to both the current application module and the voltage acquisition module, is used to calculate the real-time resistance of the pressure detection component based on the real-time voltage of the pressure detection component and the detection current. The resistance calculation module uses the formula R... t =U t / I t Calculate the resistance of the pressure sensing component at time t; where R t Let U be the resistance of the pressure sensing component at time t. t Let I be the voltage across the pressure sensing component at time t. t To detect current; A pressure calculation module, connected to the resistance calculation module, is used to calculate the pressure value of the target skin at any given moment when the microneedle component is in contact with the target skin, based on the current resistance value and the initial resistance value of the pressure detection component; the initial resistance value is the resistance value of the pressure detection component when the microneedle component is not in contact with the target skin; the pressure calculation module uses a formula... Calculate the pressure value of the target skin at time t; where P t Let t be the pressure value of the target skin, R0 be the initial resistance of the pressure detection component, and ε be the pressure-resistance change coefficient of the pressure detection component. An intensity determination module, connected to the voltage acquisition module, is used to determine the ultrasonic signal intensity based on the real-time voltage across the pressure detection component. A cycle determination module, connected to the pressure calculation module, is used to determine the needle insertion cycle based on the pressure value of the target skin. An ultrasonic drive module is connected to the mode acquisition module, the intensity determination module, the period determination module, and the ultrasonic transmitting device, respectively, and is used to generate an ultrasonic drive signal based on the ultrasonic signal intensity, the needle insertion period, and the needle insertion mode selected by the user.

2. The adaptive depth-of-action ultrasonic microneedle system according to claim 1, characterized in that, The microneedle assembly includes multiple microneedles and multiple microneedle movable parts; each microneedle is fixed to the pressure detection assembly through a microneedle movable part.

3. The adaptive depth-of-action ultrasonic microneedle system according to claim 1, characterized in that, The needle insertion modes include sine wave needle insertion mode, pulse needle insertion mode, and sawtooth wave needle insertion mode.

4. The adaptive depth-of-action ultrasonic microneedle system according to claim 3, characterized in that, When the user selects the sine wave needle insertion mode, the ultrasonic drive signal generated by the microprocessor is: Where S(t) is the ultrasonic drive signal generated by the microprocessor at time t, E is the ultrasonic signal intensity, and T is the needle insertion period.

5. The adaptive depth-of-action ultrasonic microneedle system according to claim 3, characterized in that, When the user selects pulse needle insertion mode, the ultrasonic drive signal generated by the microprocessor is: Where S(t) is the ultrasonic drive signal generated by the microprocessor at time t, E is the ultrasonic signal intensity, and T is the needle insertion period.

6. The adaptive depth-of-action ultrasonic microneedle system according to claim 3, characterized in that, When the user selects the sawtooth wave needle insertion mode, the ultrasonic drive signal generated by the microprocessor is: S(t) = Et, 0 ≤ t ≤ T; Where S(t) is the ultrasonic drive signal generated by the microprocessor at time t, E is the ultrasonic signal intensity, and T is the needle insertion period.

7. The adaptive depth-of-action ultrasonic microneedle system according to claim 1, characterized in that, The ultrasonic sound pressure generated by the ultrasonic transmitting device is: Where p is the ultrasonic sound pressure, ρ0 is the tissue density, c0 is the sound velocity, S(t) is the ultrasonic driving signal generated by the microprocessor at time t, and k w Let be the wave number and a be the radius of the sound field.

8. The adaptive depth-of-action ultrasonic microneedle system according to claim 1, characterized in that, The displacement generated by the microneedle assembly is: Where d is the displacement generated by the microneedle component, p is the ultrasonic pressure, a is the sound field radius, t' is the duration of action, and m is the mass of the microneedle component.

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