Ultrasonic probe, auxiliary positioning jig and preparation method of ultrasonic probe

Abstract

The invention provides an ultrasonic probe, an auxiliary positioning jig and a preparation method of the ultrasonic probe, a first cutting groove and a second cutting groove of a matching layer of the ultrasonic probe are correspondingly arranged and are communicated to form a piezoelectric interval, so that a piezoelectric layer forms a plurality of piezoelectric sub-units arranged at intervals, namely the piezoelectric sub-units are formed through secondary cutting. In the matching layer of the ultrasonic probe prepared by the preparation method, the piezoelectric interval between the two adjacent piezoelectric sub-units is formed by secondary cutting in opposite directions, so that the ratio of the width of the formed piezoelectric sub-units to the thickness of the piezoelectric layer can reach 1 / 60-1 / 4, and on the basis of ensuring that the processing operation is simple and feasible, the piezoelectric interval between the two piezoelectric sub-units is greatly reduced. The piezoelectric sub-unit can reach a large thickness, and the center frequency of the ultrasonic probe can be effectively reduced, so that the penetrating power of the ultrasonic probe is effectively increased, the imaging depth of the ultrasonic probe is improved, and the application range of the ultrasonic probe is expanded.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an ultrasonic probe, an auxiliary positioning fixture and a method for preparing the ultrasonic probe. Background Art

[0002] The ultrasonic probe is the core component of the ultrasonic diagnostic equipment. It is a device that transmits ultrasonic waves into the body of the object being tested and receives ultrasonic echo signals reflected from the corresponding parts. The ultrasonic diagnostic equipment converts the echo signals into images through a series of signal processing and displays the images on the display device of the diagnostic equipment.

[0003] The core part of the ultrasonic probe is the ultrasonic transducer. The piezoelectric element in the ultrasonic transducer can convert electrical pulse excitation into ultrasonic waves and can convert the reflected echo in the object into electrical signals. The ultrasonic transducer usually also includes one or more matching layers placed at the front end of the piezoelectric element layer to match the acoustic impedance between the object and the piezoelectric element, an acoustic lens placed between the matching layer and the object to form a short-axis direction of the sound beam focus, a backing placed at the rear end of the piezoelectric element layer to absorb reverse sound waves, and electrodes and lines for transmitting signals.

[0004] For ultrasound probes, the center frequency is their basic acoustic parameter. Usually, ultrasound probes are used on ultrasound diagnostic equipment, and their center frequency is 2MHz-20MHz. When used in some applications such as intravascular diagnosis, their frequency may reach 50MHz-100MHz. The lower the center frequency, the lower the acoustic attenuation of ultrasound in human tissue, and the stronger the probe's penetration. The center frequency is related to the piezoelectric material layer inside the ultrasound transducer, specifically the thickness of the piezoelectric layer. The lower the frequency, the thicker the piezoelectric layer is required.

[0005] During the specific production, lowering the center frequency of the probe will cause the probe size to increase, which is not conducive to clinical operation. If the size remains unchanged, the thickness of the piezoelectric material will increase, and the ratio of the cut depth to width will increase, making it difficult to process and manufacture, increasing the difficulty of production and leading to processing difficulties. Summary of the invention

[0006] The purpose of the present invention is to solve the technical problem that the ultrasonic probe in the prior art cannot have both low center frequency and convenient processing and manufacturing.

[0007] In order to solve the above technical problems, the present invention provides an ultrasonic probe, which includes a backing layer, a piezoelectric layer, a matching layer and an acoustic lens bonded in sequence from bottom to top, wherein the two opposite surfaces of the piezoelectric layer are respectively a first surface and a second surface;

[0008] A plurality of first grooves are provided on the first surface, and the cutting direction of the first grooves is from the first surface to the second surface along the thickness direction of the piezoelectric layer; a plurality of second grooves are provided on the second surface, and the cutting direction of the second grooves is from the second surface to the first surface along the thickness direction of the piezoelectric layer;

[0009] The cutting width of the first groove is the same as the cutting width of the second groove, and a plurality of the first grooves are arranged in a one-to-one correspondence with a plurality of the second grooves; the corresponding first grooves and the second grooves are connected to form a piezoelectric interval, so that the piezoelectric layer forms a plurality of piezoelectric sub-units arranged at intervals, and the space between two adjacent piezoelectric sub-units is the piezoelectric interval;

[0010] Wherein, the ratio of the width of the piezoelectric subunit to the thickness of the piezoelectric layer is 1 / 60 to 1 / 4.

[0011] In some embodiments of the present application, the center frequency of the ultrasound probe is 0.5 MHz to 2 MHz.

[0012] In some embodiments of the present application, the wavelength of the sound wave of the ultrasonic probe propagating in the piezoelectric layer is λ 1 , the width of each piezoelectric subunit is 1 / 60λ 1 ~1 / 2λ 1 .

[0013] In some embodiments of the present application, the wavelength of the sound wave of the ultrasonic probe propagating in the piezoelectric layer is λ 1 , the width of the piezoelectric layer is 1 / 4λ 1 ~30λ 1 .

[0014] In some embodiments of the present application, the wavelength of the sound wave of the ultrasonic probe propagating in the piezoelectric layer is λ 1 , the thickness of the piezoelectric layer is 1 / 8λ 1 ~1λ 1 .

[0015] In some embodiments of the present application, the matching layer is provided with at least one layer, and multiple matching layers are stacked in the thickness direction thereof.

[0016] In some embodiments of the present application, the wavelength of the sound wave of the ultrasonic probe propagating in the matching layer is λ 2 , the thickness of the matching layer is 1 / 8λ 2 ~1 / 2λ 2 .

[0017] In some embodiments of the present application, the thickness of the matching layer is 1 / 6λ 2 ~1 / 2λ2 .

[0018] In some embodiments of the present application, the piezoelectric layer is made of PZT piezoelectric ceramics or piezoelectric single crystals, or is made of PZT piezoelectric ceramics, piezoelectric single crystals as a substrate and a high molecular polymer material.

[0019] In some embodiments of the present application, the backing is provided with at least one layer, and multiple layers of the backing are stacked in the thickness direction of the backing.

[0020] The present invention also provides an auxiliary positioning jig, which is used for preparing the above-mentioned ultrasonic probe. The auxiliary positioning jig includes a positioning plate and at least two positioning posts arranged on the positioning plate, and the positions of the positioning posts on the positioning plate are fixed.

[0021] The present invention also provides a method for preparing an ultrasonic probe, characterized in that it is used to make the above-mentioned ultrasonic probe, and the preparation method comprises the following steps:

[0022] Positioning of the piezoelectric sheet: providing a piezoelectric sheet and an auxiliary positioning fixture, wherein the piezoelectric sheet is provided with a positioning hole; the piezoelectric sheet is sleeved on the positioning column through the positioning hole, so that the position of the piezoelectric sheet on the positioning plate is fixed;

[0023] First cutting: the piezoelectric sheet and the auxiliary positioning fixture are positioned as a whole on the cutting platform, and the cutting device selects a set cutting position relative to the positioning plate to cut the first surface of the piezoelectric sheet to form a plurality of first cutting grooves, and then the backing layer is connected to the first surface of the piezoelectric sheet;

[0024] Second cutting: the cutting device selects a set cutting position relative to the positioning plate to cut the second surface of the piezoelectric sheet, and the second surface of the piezoelectric sheet is arranged opposite to the first surface to form a plurality of second grooves on the second surface; the cutting position of the first cutting and the cutting position of the second cutting are both set positions relative to the positioning plate, so that the second groove corresponds to the cut mark of the first groove and is connected to form a complete groove, thereby obtaining a piezoelectric layer.

[0025] In some embodiments of the present application, in the first cutting step, the cutting depth of the cutting device on the first surface of the piezoelectric sheet is not less than half of the thickness of the piezoelectric sheet.

[0026] In some embodiments of the present application, in the step of positioning the piezoelectric sheet, a flexible film with a substrate is provided, and the flexible film is bonded to the second surface of the piezoelectric sheet.

[0027] In some embodiments of the present application, the wavelength of the sound wave of the ultrasonic probe propagating in the piezoelectric layer is λ 1, the thickness of the flexible film is not greater than 1 / 20λ 1 .

[0028] In some embodiments of the present application, after the second cutting is completed, a matching layer is connected to the second surface of the piezoelectric layer, and an acoustic lens is connected to the surface of the matching layer, thereby manufacturing an ultrasonic probe.

[0029] In some embodiments of the present application, after the first cutting is completed, a matching piece is connected to the second surface of the piezoelectric piece; in the second cutting step, the cutting device selects a set cutting position relative to the positioning plate to cut the second surface of the piezoelectric piece and the matching piece to form a plurality of second grooves on the second surface, and the matching piece is formed into a plurality of spaced matching sub-units, thereby obtaining a matching layer; and then an acoustic lens is connected to the surface of the matching layer, thereby obtaining an ultrasonic probe.

[0030] It can be seen from the above technical scheme that the beneficial effects of the present invention are as follows: in the ultrasonic probe, auxiliary positioning fixture and ultrasonic probe preparation method provided by the present invention, in the matching layer of the ultrasonic probe prepared by the preparation method, the piezoelectric interval between two adjacent piezoelectric sub-units is formed by secondary cutting in opposite directions, and the ratio of the width of the piezoelectric sub-unit formed in this way to the thickness of the piezoelectric layer is 1 / 60 to 1 / 4. On the basis of ensuring that the processing operation is simple and feasible, the piezoelectric sub-unit can achieve a larger thickness, which can effectively reduce the center frequency of the ultrasonic probe, thereby effectively increasing the penetration of the ultrasonic probe, thereby improving the imaging depth of the ultrasonic probe and expanding the scope of use of the ultrasonic probe. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic structural diagram of an embodiment of an ultrasonic probe of the present invention.

[0032] Figure 2 This is a frequency response test result diagram obtained through simulation of ultrasonic probe example 1 of the present invention.

[0033] Figure 3 This is a frequency response test result diagram obtained through simulation of ultrasonic probe example 2 of the present invention.

[0034] Figure 4 It is a flow chart of the method for preparing the ultrasonic probe of the present invention.

[0035] Figure 5 It is a structural schematic diagram of an embodiment of the auxiliary positioning fixture of the present invention.

[0036] Figures 6 to 10 It is a schematic diagram of the operation structure in the method for preparing the ultrasonic probe of the present invention.

[0037] The description of the accompanying drawings is as follows: 100, ultrasonic probe; 10, backing layer; 20, piezoelectric layer; 21, first surface; 22, second surface; 211, first groove; 221, second groove; 201, piezoelectric spacer; 2001, piezoelectric subunit; 2011, piezoelectric sheet; 2012, positioning hole; 30, matching layer; 301, first layer matching structure; 302, second layer matching structure; 3011, matching sheet; 40, acoustic lens; 500, auxiliary positioning fixture; 501, positioning plate; 502, positioning column; 600, flexible film. DETAILED DESCRIPTION

[0038] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations therein are essentially used for illustration purposes rather than for limiting the present invention.

[0039] In the description of the present application, it should be understood that in the embodiments shown in the drawings, the indications of directions or positional relationships (such as up, down, left, right, front and back, etc.) are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation. These descriptions are appropriate when these elements are in the positions shown in the drawings. If the descriptions of the positions of these elements change, the indications of these directions also change accordingly.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0041] At present, the lowest center frequency of ultrasound probes in the prior art is 2MHz. The acoustic attenuation coefficient in human tissue is about 1dB / cm·MHz. When using the existing ultrasound probe to transmit and receive ultrasound waves to human tissue, the attenuation is 4dB for every 1cm increase in depth. For example, when the depth reaches 25cm, the attenuation is 100dB. At this time, the echo signal is equivalent to the noise level, so it is difficult to accurately distinguish the lesion on the ultrasound image.

[0042] In view of the above technical problems, this application provides corresponding technical solutions. Specifically, see Figure 1An embodiment of the present application provides an ultrasonic probe 100, which includes a backing layer 10, a piezoelectric layer 20, a matching layer 30 and an acoustic lens 40 bonded sequentially from bottom to top, and the opposite two side surfaces of the piezoelectric layer 20 are a first surface 21 and a second surface 22 respectively.

[0043] In this embodiment, a plurality of first grooves 211 are provided on the first surface 21 of the piezoelectric layer 20, and the cutting direction of the first grooves 211 is from the first surface 21 to the second surface 22 along the thickness direction of the piezoelectric layer 20. A plurality of second grooves 221 are provided on the second surface 22 of the piezoelectric layer 20, and the cutting direction of the second grooves 221 is from the second surface 22 to the first surface 21 along the thickness direction of the piezoelectric layer 20.

[0044] The cutting width of the first groove 211 is the same as the cutting width of the second groove 221, and the plurality of first grooves 211 are arranged in one-to-one correspondence with the plurality of second grooves 221. The corresponding first grooves 211 and second grooves 221 are connected to form a piezoelectric gap 201, so that the piezoelectric layer 20 forms a plurality of piezoelectric sub-units 2001 arranged at intervals, and the space between two adjacent piezoelectric sub-units 2001 is the piezoelectric gap 201.

[0045] The ratio of the width of the piezoelectric subunit 2001 to the thickness of the piezoelectric layer 20 is 1 / 60 to 1 / 4. The center frequency of the ultrasonic probe 100 is 0.5 MHz to 2 MHz.

[0046] In this embodiment, the first groove 211 and the second groove 221 of the matching layer 30 are correspondingly arranged and connected to form a piezoelectric interval 201, so that the piezoelectric layer 20 forms a plurality of piezoelectric sub-units 2001 arranged at intervals. That is, the piezoelectric sub-unit 2001 is formed by cutting the material for preparing the piezoelectric layer 20 twice from opposite directions, and the thickness of the piezoelectric layer 20 is determined by the cutting depth of the two cuttings to form the first groove 211 and the second groove 221, and the thickness of the piezoelectric sub-unit 2001 is consistent with the thickness of the piezoelectric layer 20.

[0047] The ratio of the width of the piezoelectric sub-unit 2001 formed by bidirectional secondary cutting to the thickness of the piezoelectric layer 20 can reach 1 / 60 to 1 / 4. On the basis of ensuring the simplicity and feasibility of the processing operation, the piezoelectric sub-unit 2001 can achieve a larger thickness, which can effectively reduce the center frequency of the ultrasonic probe 100, thereby effectively increasing the penetration of the ultrasonic probe 100, and then improving the imaging depth of the ultrasonic probe 100, expanding the scope of use of the ultrasonic probe 100.

[0048] Especially for obese patients or patients with thick fat in the area to be examined, the ultrasound probe 100 of the present application can provide high-quality detection results, which is of great significance for diagnosing difficult patients such as obese patients.

[0049] Specifically, for the ultrasonic probe 100 of the present application, its center frequency is 0.5MHz to 2MHz. In actual use, taking the working frequency of 1MHz as an example, when the ultrasonic probe 100 of the present application transmits and receives ultrasonic waves to human tissue, the two-way attenuation is 2dB for every 1cm increase in depth. Compared with the ultrasonic probe in the prior art, the detection depth of the ultrasonic probe 100 of the present application can be doubled, that is, at the same imaging level, the detection depth of the ultrasonic probe 100 of the present application can be extended by 50cm, which can overcome the difficulty of detection caused by the thick fat thickness of obese patients, and ensure that the ultrasonic probe 100 can still be effectively used for detection of difficult patients such as those with obesity.

[0050] Furthermore, the piezoelectric layer 20 of the present embodiment may be made of PZT piezoelectric ceramics or piezoelectric single crystals, or made of PZT piezoelectric ceramics or piezoelectric single crystals as substrates and high molecular polymer materials.

[0051] In this embodiment, the two opposite surfaces of the piezoelectric layer 20 are respectively a first surface 21 and a second surface 22, and the extension direction of the first surface 21 toward the second surface 22 is the sound wave emission direction of the ultrasonic probe 100. The backing layer 10 is disposed on the first surface 21 of the piezoelectric layer 20, and the matching layer 30 is disposed on the second surface 22 of the piezoelectric layer 20.

[0052] The piezoelectric layer 20 includes a plurality of piezoelectric sub-units 2001 arranged at intervals, which can be made into a 1D array, a 1.5D array or a 2D array as required. The piezoelectric sub-units 2001 vibrate to generate ultrasonic signals, which are Figure 1 The arrow in the middle indicates the direction of ultrasound waves transmitted from the ultrasound probe 100. At the same time, the piezoelectric subunit 2001 can receive ultrasound waves (such as ultrasound waves reflected from a target object) and convert the ultrasound waves into electrical signals, which are transmitted to a receiver of the ultrasound imaging system and processed into images.

[0053] In this embodiment, the wavelength of the sound wave of the ultrasonic probe 100 propagating in the piezoelectric layer 20 is λ 1 , the width w of each piezoelectric subunit 2001 is 1 / 60λ 1 ~1 / 2λ 1 , the width l of the piezoelectric layer 20 is 1 / 4λ 1 ~30λ 1 , the thickness t of the piezoelectric layer 20 is 1 / 8λ 1 ~1λ 1 The thickness t of the piezoelectric subunit 2001 is consistent with the thickness t of the piezoelectric layer 20, and both are 1 / 8λ. 1 ~1λ 1 .

[0054] In this embodiment, the ratio of the width of the piezoelectric subunit 2001 to the thickness of the piezoelectric layer 20, that is, the ratio of the width of the piezoelectric subunit 2001 to its own thickness is 1 / 60 to 1 / 4. In the existing ultrasound probe 100, the piezoelectric element is generally composed of a plurality of piezoelectric wire-shaped array elements arranged in parallel, which are formed by cutting a complete piezoelectric sheet plated with electrodes, and the ratio of the width of the existing piezoelectric wire-shaped array element to its own thickness is 1 / 4 to 1.

[0055] For the existing ultrasonic probe 100, when the center frequency is reduced, the thickness of the piezoelectric array element increases, and the cutting depth-to-width ratio will also increase while keeping the size of the acoustic window unchanged. Increasing the cutting depth-to-width ratio requires a larger exposure of the cutting blade and a thinner blade, which will dramatically increase the blade loss. At the same time, the rigidity of the blade of the cutting equipment is reduced, and it is easy to deform during the cutting process, affecting the consistency between the knife mark and the size and shape of the array element, thereby reducing the image quality, and even directly damaging the blade and the workpiece, making it impossible to process.

[0056] For the ultrasonic probe 100 of the present application, the ratio of the width of the piezoelectric unit 2001 to its thickness is 1 / 60 to 1 / 4, so that the cutting depth of the blade can be doubled while ensuring the cutting quality, thereby reducing the center frequency of the processable probe to less than 1 / 2 of the original. This solves the problem of how to keep the size of the probe acoustic window unchanged while reducing the center frequency and causing processing difficulties, making it possible for the ultrasonic probe 100 to have a low center frequency and be easy to process.

[0057] In this embodiment, the center frequency of the ultrasonic probe 100 is 0.5 MHz to 2 MHz, which can not only meet the requirement of improving the penetration of the ultrasonic probe 100, but also facilitate the processing and manufacturing of the ultrasonic probe 100. The width w of the piezoelectric unit 2001 is 1 / 60λ 1 ~1 / 2λ 1 The width l of the piezoelectric layer 20 is 1 / 4λ 1 ~30λ 1 The setting can meet the size requirements of the ultrasonic probe 100 and optimize the overall structure of the ultrasonic probe 100.

[0058] The thickness t of the piezoelectric layer 20 is set to 1 / 8λ 1 ~1λ 1 It can not only meet the requirement of lower center frequency of the ultrasonic probe 100, but also effectively ensure the size requirement of the ultrasonic probe 100 itself, avoid the ultrasonic probe 100 being too large or too long, and ensure that the ultrasonic probe 100 can adapt to various detection parts and detection areas.

[0059] The backing layer 10 of this embodiment is disposed on the first surface 21 of the piezoelectric layer 20, and the backing layer 10 is bonded and fixed to the piezoelectric layer 20. The backing layer 10 can be configured to absorb the piezoelectric subunit 2001 along the first surface 21 of the piezoelectric layer 20. Figure 1 The arrows shown indicate ultrasonic waves directed in opposite directions, and stray ultrasonic waves deflected by the ultrasonic probe 100 are attenuated, and the bandwidth and axial resolution of the ultrasonic signal thereof can be increased by the backing.

[0060] In some embodiments, the backing layer 10 may be configured as a single-layer structure or a multi-layer structure. The impedance of the backing layer 10 may be greater than the impedance of the piezoelectric sub-unit 2001 or may be configured as less than the impedance of the piezoelectric sub-unit 2001 .

[0061] The backing layer 10 can not only serve as the base structure of other components in the ultrasonic probe 100 to provide support for structures such as the piezoelectric layer 20 and the matching layer 30 to ensure the overall structural strength of the ultrasonic probe 100, but can also effectively absorb useless sound waves radiated from the back of the piezoelectric unit 2001 to ensure high-quality detection effects of the ultrasonic probe 100.

[0062] Further, the matching layer 30 of the present embodiment is arranged on the second surface 22 of the piezoelectric layer 20, and the matching layer 30 is bonded and fixed to the piezoelectric layer 20. The matching layer 30 can be a material arranged between the piezoelectric subunit 2001 and the target object to be imaged. By arranging the matching layer 30 between the two, the ultrasonic wave can first pass through the matching layer 30 and be emitted from the matching layer 30, thereby reducing the possibility of reflection at the target object, which is conducive to more propagation of the sound wave energy to the target object, and to a certain extent, it serves the purpose of improving the detection depth. The matching layer 30 can shorten the pulse length of the ultrasonic signal, thereby increasing the axial resolution of the signal.

[0063] In some embodiments, the wavelength of the sound wave of the ultrasonic probe 100 propagating in the matching layer 30 is λ 2 , the thickness of the matching layer is 1 / 8λ 2 ~1 / 2λ 2 This arrangement can effectively prevent the matching layer 30 from unnecessary sound wave attenuation, and can also achieve matching between the ultrasonic probe 100 and the tissue, balance the acoustic impedance between the ultrasonic probe 100 and the human tissue, further reduce the reflection generated when the ultrasonic wave propagates at interfaces with different impedance values, effectively reduce energy loss, ensure that more sound wave energy can be incident on the human body, and ensure smooth propagation of the ultrasonic wave.

[0064] In some other embodiments, the thickness of the matching layer 30 may also be set to 1 / 6λ 2 ~1 / 2λ 2 This configuration can meet the size requirements of the ultrasonic probe 100 and optimize the overall structure of the ultrasonic probe 100 .

[0065] The matching layer 30 of this embodiment is provided with two layers, and the two matching layers 30 are respectively a first matching structure 301 and a second matching structure 302. The first matching structure 301 and the second matching structure 302 are stacked in their own thickness direction. Specifically, the first matching structure 301 is arranged on the second surface 22 of the piezoelectric layer 20, and the second matching structure 302 is arranged on the surface of the first matching structure 301.

[0066] In other examples of this embodiment, the matching layer 30 can also be set to one layer, three layers, five layers, etc., which are not limited here. The corresponding number of layers can be set accordingly according to specific detection needs. In addition, in this embodiment, an acoustic lens 40 is provided on the surface of the matching layer 30, and the acoustic lens 40 is arranged on the surface of the second matching structure. The acoustic lens 40 can converge or diverge sound waves to enhance the working effect of the ultrasound probe 100.

[0067] The center frequency of the ultrasonic probe 100 of the present application is measured, and examples 1 and 2 of the ultrasonic probe 100 of the present application are provided, which are frequency responses of the ultrasonic probe 100 obtained through simulation respectively.

[0068] The ultrasonic probe 100 example 1 uses PZT5H as the material of the piezoelectric layer 20, and the size parameters of the piezoelectric subunit 2001 are as follows: thickness t = 1080 um ≈ 0.4λ 1 , width w = 0.15 mm ≈ 1 / 18 λ 1 , the width of the piezoelectric layer 20 is l = 12 mm ≈ 4.5λ 1 ; and use a single-layer backing layer 10 with an acoustic impedance of 3 Mrayl, a double-layer matching layer 30 with characteristic impedances of 8.2 MRayl and 2.1 MRayl, and an acoustic lens 40 made of RTV silicone rubber.

[0069] The ultrasonic probe 100 example 2 uses PZT5H as the material of the piezoelectric layer 20, and the size parameters of the piezoelectric subunit 2001 are as follows: thickness t = 1720 um ≈ 0.43 λ 1 , w=0.12mm≈1 / 33λ 1 , the width of the piezoelectric layer 20 is l = 12 mm ≈ 3λ 1 ; and use a single-layer backing layer 10 with an acoustic impedance of 3 Mrayl, a double-layer matching layer 30 with characteristic impedances of 8.2 MRayl and 2.1 MRayl, and an acoustic lens 40 made of RTV silicone rubber.

[0070] The frequency response of the ultrasonic probe 100 example 1 obtained by simulation is as follows Figure 2 As shown, the frequency response of the ultrasonic probe 100 example 2 obtained by simulation is as follows Figure 3shown.

[0071] Depend on Figure 2 It can be seen that the center frequency of the ultrasonic probe 100 example 1 at -6dB is 1.52MHz, and the detection depth of the ultrasonic probe 100 example 1 can be increased by more than 1.3 times compared with the probe with a center frequency of 2MHz. Figure 3 It can be seen that the center frequency of the ultrasonic probe 100 Example 2 at -6dB is 0.98MHz, and the detection depth of the ultrasonic probe 100 Example 2 can be increased by more than 2 times compared with the probe with a center frequency of 2MHz.

[0072] Based on Example 1 and Example 2 of the ultrasonic probe 100 of the present application, it can be seen that the center frequency of the ultrasonic probe 100 of the present application can reach 0.5MHz to 2MHz. The detection depth of the ultrasonic probe 100 with such a center frequency can be improved, which is conducive to the ultrasonic probe 100 being suitable for the detection of deep tissues.

[0073] Furthermore, an embodiment of the present application also provides a method for preparing an ultrasonic probe 100, which can prepare an ultrasonic probe 100 of the above-mentioned structural form. The structure of the ultrasonic probe 100 has been described above and will not be repeated here. Figure 4 As shown, the preparation method of this embodiment includes the following steps:

[0074] Step S10, positioning the piezoelectric sheet: providing a piezoelectric sheet and an auxiliary positioning fixture, wherein the piezoelectric sheet is provided with a positioning hole; sleeve the piezoelectric sheet on the positioning column through the positioning hole, so that the position of the piezoelectric sheet on the positioning plate is fixed;

[0075] Step S20, first cutting: the piezoelectric sheet and the auxiliary positioning fixture are positioned as a whole on the cutting platform, and the cutting device selects a set cutting position relative to the positioning plate to cut the first surface of the piezoelectric sheet to form a plurality of first cutting grooves, and then the backing layer is connected to the first surface of the piezoelectric sheet;

[0076] Step S30, second cutting: the cutting device selects a set cutting position relative to the positioning plate to cut the second surface of the piezoelectric sheet, and the second surface of the piezoelectric sheet is arranged relative to the first surface to form a plurality of second grooves on the second surface; the cutting position of the first cutting and the cutting position of the second cutting are both set positions relative to the positioning plate, so that the second groove corresponds to the cut mark of the first groove and is connected to form a complete groove, thereby obtaining a piezoelectric layer.

[0077] like Figure 5 As shown, this embodiment further provides an auxiliary positioning fixture 500 , which includes a positioning plate 501 and at least two positioning posts 502 disposed on the positioning plate 501 , and the positions of the positioning posts 502 on the positioning plate 501 are fixed.

[0078] For the preparation method of the present application, a positioning hole 2012 can be set on the piezoelectric sheet 2011, and the positioning hole 2012 of the piezoelectric sheet 2011 is matched with the positioning column 502, so that the piezoelectric sheet 2011 can be positioned at a set position on the positioning plate 501. When the piezoelectric sheet 2011 is cut for the first time and the second time, based on the fixed position of the piezoelectric sheet 2011 on the positioning plate 501, and the cutting position of the first cutting and the cutting position of the second cutting are both set positions relative to the positioning plate 501, the second groove 221 can correspond to the cut of the first groove 211, so that the cuts of the two cuttings are accurately connected, ensuring that the shapes of the second groove 221 and the first groove 211 are aligned.

[0079] In the preparation method of the present application, the first cutting and the second cutting are in opposite directions, so that the cutting depths can be superimposed. In some embodiments, the surface of the piezoelectric sheet 2011 corresponding to the direction of the sound wave emission can be cut in the first cutting operation, and the surface of the piezoelectric sheet 2011 away from the direction of the sound wave emission can be cut in the second cutting operation; in some embodiments, the surface of the piezoelectric sheet 2011 away from the direction of the sound wave emission can be cut in the first cutting operation, and the surface of the piezoelectric sheet 2011 corresponding to the direction of the sound wave emission can be cut in the second cutting operation. Further, in combination with Figure 6 In step S10, a piezoelectric sheet 2011, an auxiliary positioning fixture 500 and a flexible film 600 with a substrate are provided. The flexible film 600 has a certain viscosity, and the substrate is used to support the flexible film 600, and the substrate can be removed from the flexible film 600.

[0080] The piezoelectric sheet 2011 is sleeved on the positioning column 502 through the positioning hole 2012, so that the position of the piezoelectric sheet 2011 on the positioning plate 501 is fixed. The two opposite surfaces of the piezoelectric sheet 2011 are respectively a first surface 21 and a second surface 22. A flexible film 600 with a substrate is bonded to the second surface 22 of the piezoelectric sheet 2011, and the size of the flexible film 600 is larger than that of the piezoelectric sheet 2011.

[0081] In some embodiments, the thickness of the flexible film 600 itself is not greater than the wavelength λ 1 This configuration can not only ensure the structural strength of the subsequent connection between the matching layer 30 and the piezoelectric layer 20 and ensure the structural stability of the overall preparation of the ultrasonic probe 100, but also reduce the impact on ultrasonic emission and ensure the penetration of the ultrasonic wave of the ultrasonic probe 100.

[0082] In some other embodiments, the thickness of the flexible film 600 itself is not greater than the wavelength λ 1 1 / 100 of the value of the ultrasonic wave to further avoid affecting the emission of the ultrasonic wave and ensure the detection effect of the ultrasonic probe 100.

[0083] In step S20, combining Figure 7 , perform the first cutting, position the piezoelectric sheet 2011 and the auxiliary positioning fixture 500 as a whole on the cutting platform, and the cutting equipment selects the set cutting position relative to the positioning plate 501 to cut the first surface 21 of the piezoelectric sheet 2011 to form a plurality of first cutting grooves 211.

[0084] In this embodiment, in the first cutting step, the cutting depth of the first surface 21 of the piezoelectric sheet 2011 by the cutting device is not less than half of the thickness of the piezoelectric sheet 2011. Figure 8 and Fig. 9 After the first cutting is completed, the backing layer 10 is bonded to the first surface 21 of the piezoelectric sheet 2011. In addition, the substrate on the flexible film 600 is removed, and the portion exceeding the size range of the piezoelectric sheet 2011 is removed. The piezoelectric sheet 2011 and the auxiliary positioning fixture 500 are then positioned as a whole on the cutting platform to wait for the second cutting.

[0085] In some other embodiments, the flexible film 600 may not be removed but remain in the overall structure, but the flexible film must not affect the transmission and receiving performance of the ultimately manufactured ultrasound probe 100 .

[0086] In addition, in some other embodiments, a conductive layer may be provided on the flexible film 600. The conductive layer may be made of metal and may be provided on the flexible film 600 by electroplating. The conductive layer may be used to connect electrodes to achieve the function of electrical connection and conduction.

[0087] In step S30, combining Fig.10 , a second cutting is performed, and the cutting device selects a set cutting position relative to the positioning plate 501 to cut the second surface 22 of the piezoelectric sheet 2011 to form a plurality of second grooves 221 on the second surface 22. The cutting position of the first cutting and the cutting position of the second cutting are both set positions relative to the positioning plate 501, so that the cut marks of the second grooves 221 and the first grooves 211 can correspond to each other and connect to form a complete groove, thereby obtaining the piezoelectric layer 20.

[0088] After the piezoelectric layer 20 is prepared, the matching layer 30 is bonded to the piezoelectric layer 20 through the flexible film 600 disposed on the second surface 22 of the piezoelectric layer 20. After the matching layer 30 is bonded, the acoustic lens 40 is bonded to the surface of the matching layer 30, thereby completing the preparation of the ultrasonic probe 100.

[0089] In other examples of this embodiment, a material for preparing the matching layer 30, namely a matching sheet 3011, may be provided. After the first cutting is completed, the matching sheet 3011 is first connected to the second surface 22 of the piezoelectric sheet 2011, and the connection between the two may be bonding.

[0090] Combination Figure 5 As shown, the matching sheet 3011 is also provided with a positioning hole 2012, and the matching sheet 3011 is sleeved on the positioning column 502 through the positioning hole 2012, so that the position of the matching sheet 3011 on the positioning plate 501 is fixed. In step S30, when performing the second cutting, the cutting device selects the set cutting position relative to the positioning plate 501 to cut the second surface 22 of the piezoelectric sheet 2011 and the matching sheet 3011 at the same time, so as to form a plurality of second cutting grooves 221 on the second surface 22 of the piezoelectric sheet 2011, and form a plurality of matching sub-units arranged at intervals on the matching sheet 3011, and the plurality of matching sub-units constitute the matching layer 30, thereby completing the preparation of the matching layer 30.

[0091] After the matching layer 30 is prepared, the acoustic lens 40 is bonded to the surface of the matching layer 30, thereby completing the preparation of the ultrasonic probe 100. In the above bonding process, a corresponding bonding jig can be used to ensure the positioning and alignment of the positions of the structures during bonding, thereby ensuring the bonding accuracy between the structures.

[0092] With respect to the preparation method of the present embodiment, in the matching layer of the ultrasonic probe obtained by the preparation method, the piezoelectric interval between two adjacent piezoelectric sub-units is formed by secondary cutting in opposite directions, so that the ratio of the width of the piezoelectric sub-unit formed in this way to the thickness of the piezoelectric layer can reach 1 / 60 to 1 / 4. On the basis of ensuring the simplicity and feasibility of the processing operation, the piezoelectric sub-unit can achieve a larger thickness, which can effectively reduce the center frequency of the ultrasonic probe, thereby effectively increasing the penetration of the ultrasonic probe, thereby improving the imaging depth of the ultrasonic probe and expanding the use range of the ultrasonic probe.

[0093] Although the present invention has been described with reference to several typical embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Since the present invention can be embodied in a variety of forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims, so all changes and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. An ultrasonic probe, characterized in that: It includes a backing layer, a piezoelectric layer, a matching layer and an acoustic lens bonded sequentially from bottom to top, wherein two opposite surfaces of the piezoelectric layer are respectively a first surface and a second surface; A plurality of first grooves are provided on the first surface, and the cutting direction of the first grooves is from the first surface toward the second surface along the thickness direction of the piezoelectric layer; A plurality of second grooves are provided on the second surface, and the cutting direction of the second grooves is from the second surface toward the first surface along the thickness direction of the piezoelectric layer; The cutting width of the first groove is the same as the cutting width of the second groove, and a plurality of the first grooves are arranged in a one-to-one correspondence with a plurality of the second grooves; the corresponding first grooves and the second grooves are connected to form a piezoelectric interval, so that the piezoelectric layer forms a plurality of piezoelectric sub-units arranged at intervals, and the space between two adjacent piezoelectric sub-units is the piezoelectric interval; Wherein, the ratio of the width of the piezoelectric subunit to the thickness of the piezoelectric layer is 1 / 60 to 1 / 4.

2. The ultrasonic probe according to claim 1, characterized in that: The central frequency of the ultrasonic probe is 0.5 MHz to 2 MHz.

3. The ultrasonic probe according to claim 1, characterized in that: The wavelength of the sound wave of the ultrasonic probe propagating in the piezoelectric layer is λ1, and the width of each of the piezoelectric sub-units is 1 / 60λ1 to 1 / 2λ1.

4. The ultrasonic probe according to claim 1, characterized in that: The wavelength of the sound wave of the ultrasonic probe propagating in the piezoelectric layer is λ1, and the width of the piezoelectric layer is 1 / 4λ1 to 30λ1.

5. The ultrasonic probe according to claim 1, characterized in that: The wavelength of the sound wave of the ultrasonic probe propagating in the piezoelectric layer is λ1, and the thickness of the piezoelectric layer is 1 / 8λ1 to 1λ1.

6. The ultrasonic probe according to claim 1, characterized in that: The matching layer is provided with at least one layer, and a plurality of matching layers are stacked in a thickness direction thereof.

7. The ultrasonic probe according to claim 1, characterized in that: The wavelength of the sound wave of the ultrasonic probe propagating in the matching layer is λ2, and the thickness of the matching layer is 1 / 8λ2 to 1 / 2λ2.

8. The ultrasonic probe according to claim 1 or 7, characterized in that: The thickness of the matching layer is 1 / 6λ2 to 1 / 2λ2.

9. The ultrasonic probe according to claim 1, characterized in that: The piezoelectric layer is made of PZT piezoelectric ceramics or piezoelectric single crystals, or is made of PZT piezoelectric ceramics, piezoelectric single crystals as substrates and high molecular polymer materials.

10. The ultrasonic probe according to claim 1, characterized in that: The backing is provided with at least one layer, and a plurality of layers of the backing are stacked in a thickness direction thereof.

11. An auxiliary positioning fixture, characterized in that: The auxiliary positioning jig is used for preparing the ultrasonic probe according to any one of claims 1 to 10, and the auxiliary positioning jig comprises a positioning plate and at least two positioning posts arranged on the positioning plate, and the positions of the positioning posts on the positioning plate are fixed.

12. A method for preparing an ultrasonic probe, characterized in that: Used to manufacture the ultrasonic probe according to any one of claims 1 to 10, the preparation method comprises the following steps: Positioning of the piezoelectric sheet: providing a piezoelectric sheet and the auxiliary positioning fixture as claimed in claim 11, wherein the piezoelectric sheet is provided with a positioning hole; the piezoelectric sheet is sleeved on the positioning column through the positioning hole, so that the position of the piezoelectric sheet on the positioning plate is fixed; First cutting: the piezoelectric sheet and the auxiliary positioning fixture are positioned as a whole on the cutting platform, and the cutting device selects a set cutting position relative to the positioning plate to cut the first surface of the piezoelectric sheet to form a plurality of first cutting grooves, and then the backing layer is connected to the first surface of the piezoelectric sheet; Second cutting: the cutting device selects a set cutting position relative to the positioning plate to cut the second surface of the piezoelectric sheet, and the second surface of the piezoelectric sheet is arranged opposite to the first surface to form a plurality of second grooves on the second surface; the cutting position of the first cutting and the cutting position of the second cutting are both set positions relative to the positioning plate, so that the second groove corresponds to the cut mark of the first groove and is connected to form a complete groove, thereby obtaining a piezoelectric layer.

13. The preparation method according to claim 12, characterized in that: In the first cutting step, the cutting device cuts the first surface of the piezoelectric sheet to a depth not less than half the thickness of the piezoelectric sheet.

14. The preparation method according to claim 12, characterized in that: In the step of positioning the piezoelectric sheet, a flexible film with a substrate is provided, and the flexible film is bonded to the second surface of the piezoelectric sheet.

15. The preparation method according to claim 14, characterized in that: The wavelength of the sound wave of the ultrasonic probe propagating in the piezoelectric layer is λ1, and the thickness of the flexible film is not greater than 1 / 20λ1.

16. The preparation method according to claim 12, characterized in that: After the second cutting is completed, a matching layer is connected to the second surface of the piezoelectric layer, and an acoustic lens is connected to the surface of the matching layer, thereby manufacturing an ultrasonic probe.

17. The preparation method according to claim 12, characterized in that: After the first cutting is completed, a matching piece is connected to the second surface of the piezoelectric piece; in the second cutting step, the cutting device selects a set cutting position relative to the positioning plate to cut the second surface of the piezoelectric piece and the matching piece to form a plurality of second grooves on the second surface, and the matching piece is formed into a plurality of matching sub-units arranged at intervals, thereby obtaining a matching layer; and then an acoustic lens is connected to the surface of the matching layer, thereby obtaining an ultrasonic probe.

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