Imaging device for blood vessel

Abstract

This invention provides an imaging device. The imaging device includes a coil array and a control module. The coil array includes a plurality of coils. The control module is coupled to the coil array and includes an eddy current measurement unit and an imaging unit. The eddy current measurement unit is used to drive the plurality of coils to perform eddy current induction measurement to obtain the eddy current measurement results. The imaging unit is used to form an eddy current induction image based on the eddy current measurement results.

Description

[Technical Field]

[0001] The present invention relates to an imaging device; in particular to an imaging device for imaging after eddy current induction measurement through a coil array. [Previous Technology]

[0002] Medical images not only provide information about the area to be observed (e.g., a lesion), but also show the interaction between the observed area and its surrounding tissues. Therefore, compared to sound or other auxiliary information, people are accustomed to using medical images to have a more comprehensive observation of the area to be observed. With the invention of various medical applications, the methods of obtaining medical images are no longer limited to hospitals or clinics. In the prior art, medical images can be obtained through portable ultrasound devices or mechanisms such as bioelectrical impedance analysis.

[0003] For example, ultrasound is commonly used clinically for imaging arteries, the heart, breasts, and other organs, helping patients to regularly track and monitor the health of their organs. For instance, carotid artery ultrasound can be used to examine the surface and interior of blood vessel walls. However, ultrasound usually requires professional operation; the average person cannot perform long-term, real-time monitoring using ultrasound. On the other hand, ultrasound requires applying an ultrasound coupling agent to the skin to reduce acoustic impedance differences. However, ultrasound coupling agents are wet gels, which may cause allergic reactions in some users with prolonged use. Furthermore, the coupling agent can harden over time, affecting image quality. Therefore, ultrasound is not suitable for long-term measurements. Additionally, ultrasound probes are expensive, making it less cost-effective for home or personal use.

[0004] The principle of bioelectrical impedance analysis (BIA) is to inject current into the skin using attached electrodes and capture the voltage to calculate bioimpedance. However, a common technical problem in biomedical impedance sensors is that the high contact impedance between the electrodes and the skin reduces signal measurement quality and affects the accuracy of physiological parameter monitoring. Because the electrodes need to be tightly attached to the skin, air gaps can easily form at the point of contact with the skin under different curvatures of the human body, increasing the contact impedance between the skin and the electrodes, thus failing to reflect the accurate impedance value. More importantly, since the principle of biomedical impedance sensors is to input an excitation current into the human body and simultaneously measure the voltage change caused by vascular pulses to calculate the impedance change, the excitation current follows an isotropic path after entering the skin. Due to impedance relationships, the excitation current mostly chooses the path with lower impedance. This limitation of the current impedance path restricts bioelectrical impedance imaging to the superficial layer of the skin, which is not conducive to imaging deep arteries and organs in the body.

[0005] Therefore, there is a need for imaging technology that is inexpensive and whose measurements are not easily affected by the contact between the probe and the skin. [Summary of the Invention]

[0006] Therefore, the present invention provides an imaging device to effectively overcome the problems encountered by the prior art.

[0007] More specifically, one of the objects of the present invention is to provide an imaging device that can achieve non-contact, coupling agent-free, low-cost, or deep target imaging.

[0008] In one specific embodiment, the present invention provides an imaging device. The imaging device includes a coil array and a control module. The coil array includes a plurality of coils. The control module is coupled to the coil array and includes an eddy current measurement unit and an imaging unit. The eddy current measurement unit is used to drive the plurality of coils to perform eddy current induction measurement to obtain a plurality of eddy current measurement results. The imaging unit is used to form an eddy current induction image based on the plurality of eddy current measurement results.

[0009] In one embodiment, the eddy current induction measurement includes a first eddy current induction measurement; wherein the first eddy current induction measurement corresponds to a first transmission frequency to generate a first eddy current induction image corresponding to a first depth.

[0010] In one embodiment, the current sensing measurement further includes a second eddy current sensing measurement; wherein the second eddy current sensing measurement corresponds to a second transmission frequency to generate a second eddy current sensing image corresponding to a second depth, wherein the imaging unit forms a depth image with a depth value based on the first eddy current sensing image and the second eddy current sensing image.

[0011] In one embodiment, each of the plurality of coils has a first coil unit and a second coil unit, the center of the first coil unit and the center of the second coil unit overlapping each other.

[0012] In one embodiment, the control module further includes a coil selection unit, which is used to select one of the first coil unit and the second coil unit for eddy current induction measurement.

[0013] In one embodiment, the control module further includes a transmission frequency selection unit, which is used to select the transmission frequency when the eddy current measurement unit drives the complex coils to perform eddy current induction measurement.

[0014] In one embodiment, the transmit frequency selection unit includes an adjustable passive element array coupled to a complex coil to adjust the AC characteristics of the complex coil.

[0015] In one embodiment, the control module further includes a channel selection unit coupled to the coil array and used to select at least one of the complex coils to be coupled to the eddy current measurement unit for eddy current induction measurement.

[0016] In one embodiment, the channel selection unit includes a first direction selection unit and a second direction selection unit.

[0017] In one embodiment, each of the complex coils corresponds to a pixel coordinate on the eddy current induction image.

[0018] In one embodiment, the coil array is a ring array.

[0019] In one embodiment, the eddy current measurement unit is further used to perform baseline correction measurement to obtain a baseline value; wherein the imaging unit corrects the eddy current induced image based on the baseline value.

[0020] As described above, eddy current induction measurement is performed through a coil array, achieving non-contact measurement without the need for any coupling agent. Furthermore, eddy current induction can reach different depths based on the emitted electromagnetic signals, thereby enabling imaging of targets at different depths. In terms of cost, the coils and control circuitry can be implemented using various mature circuit manufacturing technologies, effectively controlling costs compared to ultrasound probes. Therefore, the imaging device of this invention is advantageous for application in personal care or long-term and / or real-time monitoring.

Implementation Method

[0032] Any reference to elements referred to herein by names such as "first," "second," etc., does not generally limit the number or order of these elements. Rather, these names are used herein as a convenient way to distinguish two or more elements or instances of elements. Therefore, it should be understood that the names "first," "second," etc., in the claim do not necessarily correspond to the same names in the written description. Furthermore, it should be understood that references to first and second elements do not imply that only two elements can be used or that the first element must precede the second element. The terms "comprising," "including," "having," "containing," etc., as used herein are open-ended, meaning that they include but are not limited to.

[0033] The term “coupled” is used herein to refer to a direct or indirect electrical coupling between two structures. For example, in one example of indirect electrical coupling, one structure may be coupled to another structure via a passive element such as a resistor, capacitor, or inductor.

[0034] In this invention, the terms "exemplary" and "for example" are used to mean "serving as an example, instance, or illustration." Any implementation or aspect described herein as "exemplary" or "for example" is not necessarily to be construed as preferred or advantageous over other aspects of the invention. The terms "about" and "approximately" as used herein with respect to specified values ​​or characteristics are intended to mean within a certain value (e.g., 10%) of the specified value or characteristic.

[0035] One specific embodiment of the present invention is an imaging device. Please refer to FIG1, which illustrates a schematic diagram of the imaging device 100. The imaging device 100 includes a coil array 110 and a control module 120. The coil array 110 includes a plurality of coils 111. The control module 120 is coupled to the coil array 110 and includes an eddy current measurement unit 121 and an imaging unit 122. The eddy current measurement unit 121 is used to drive the plurality of coils 111 to perform eddy current induction measurement to obtain a plurality of eddy current measurement results MR. The imaging unit 122 is used to form an eddy current induction image IM based on the plurality of eddy current measurement results MR.

[0036] As shown in FIG. 1, the coil array 110 is an array formed by a plurality of coils 111 (e.g., N x M coils). The plurality of coils 111 can preferably be integrated on a flexible substrate to form the coil array 110, thereby the form of the coil array 110 will not be affected by the arrangement of the plurality of coils 111, but is not limited thereto. In one embodiment, the coil array 110 can be coated with a biocompatible material. For example, the coil array 110 can be coated with polydimethylsiloxane (PDMS), SEBS, or biocompatible silicone. In this embodiment, the coated coil array 110 can have better biocompatibility, water resistance, and / or dust resistance, thereby reducing the possibility of discomfort or allergies to the test subject during measurement due to the influence of the external environment on the coil array 110.

[0037] In one embodiment, the coil array 110 may include a shielding element disposed between the coil array 110 and the control module 120. By using a shielding element made of a shielding material or a circuit that cancels electromagnetic signals, the shielding element disposed between the coil array 110 and the control module 120 can reduce interference from the coil array 110 to the control module 120, such as interference in the circuit and electromagnetic interference from the environment. The shielding element can increase the effectiveness of magnetic coupling and improve the signal resolution and signal-to-noise ratio when the coil array 110 performs eddy current induction measurement.

[0038] The control module 120 is, for example, a module comprised of a programmable processor. The programmable processor, such as a microprocessor, FPGA, ASIC, or SoC, controls the various units (e.g., eddy current measurement unit 121 and imaging unit 122) within the control module 120. In one embodiment, the programmable processor can also be a programmable user device such as a computer, smartphone, or laptop. In this embodiment, the various units within the control module 120 can be individual circuit units or implemented using internal components of the user device. For example, the user device can be coupled to an external eddy current measurement unit 121 or drive the coil array 110 using internal components to perform eddy current induction measurement. After receiving the eddy current induction measurement results, the user device uses an external imaging unit 122 or an internal component of the user device (e.g., a graphics processing unit (GPU)) as the imaging unit 122 to perform calculations and form an eddy current induction image IM. By using a user device as the control module 120, the imaging device 100 can be integrated with existing electronic products, which is more conducive to reducing costs and promoting its application to personal use or long-term monitoring.

[0039] In one embodiment, at least a portion of the control module 120 and the coil array 110 can be encapsulated and integrated using a biocompatible material. At least a portion of the control module 120 may be, for example, the eddy current measurement unit 121 or the entire control module 120. Encapsulating at least a portion of the control module 120 and the coil array 110 with a biocompatible material increases overall moisture resistance, preventing environmental factors (e.g., frequent alcohol disinfection) from affecting the lifespan of the device or coils, thereby increasing overall reliability. Furthermore, encapsulation with a completely insulating biocompatible material can reduce electrical safety risks such as leakage. In this embodiment, the control module 120 and / or the eddy current measurement unit 121 can be powered by a battery, and can be charged wirelessly if needed.

[0040] The eddy current measurement unit 121 drives the complex coils 111 to perform eddy current induction measurement. Specifically, the complex coils 111 receive an excitation signal from the eddy current measurement unit 121, causing them to generate an excitation electromagnetic signal due to electromagnetic effects. The excitation electromagnetic signal is emitted in the same direction to the area to be measured. Blood or ionic liquid in the area to be measured can be considered as a planar conductor and will be stimulated by the excitation electromagnetic signal to generate corresponding eddy currents. The generation of eddy currents is related to the area considered as a planar conductor; in other words, the generation of eddy currents will be related to the concentration or volume of blood or ionic liquid in the area to be measured. For example, vasoconstriction or vasodilation in the area to be measured, embolism in blood vessels causing uneven blood flow velocity, or abnormal concentration of blood vessels such as tumors in the area to be measured will all affect the generation of eddy currents. The eddy currents will generate a feedback electromagnetic signal, and after the complex coils 111 receive the feedback electromagnetic signal, they will cause the complex coils 111 to generate a corresponding eddy current measurement result MR. It should be noted that the present invention is not limited to the circuit architecture of the eddy current measurement unit 121. For example, the eddy current measurement unit 121 may provide an AC signal to drive the complex coils 111 to generate an electromagnetic signal, or provide a DC signal and then drive the complex coils 111 to generate an electromagnetic signal through a DC-to-AC converter such as a resonant circuit.

[0041] After receiving the corresponding eddy current measurement results MR generated by the feedback electromagnetic signals from the complex coils 111, the imaging unit 122 can, for example, form an eddy current induction image IM based on the coordinate positions of the complex coils 111 and the corresponding eddy current measurement results MR. In other words, each of the complex coils 111 corresponds to a pixel coordinate on the eddy current induction image IM. The eddy current induction image IM can be formed into an image with grayscale or color scale differences according to the magnitude of the characteristic signal (e.g., the amount of frequency change or the amount of inductance change). This presents the difference between obvious and inconspicuous areas of eddy current generation in the area under test. It should be noted that the imaging unit 122 can be a computer-readable medium that, through stored program instructions, enables the GPU or processor to generate the eddy current induction image IM.

[0042] In one embodiment, referring to FIG2, the eddy current induction measurement includes a first eddy current induction measurement; wherein the first eddy current induction measurement corresponds to a first transmission frequency to generate a first eddy current induction image IM1 corresponding to a first depth D1. Specifically, a plurality of coils 111 transmit excitation electromagnetic signals at the same transmission frequency to achieve the same depth. Thus, the first eddy current induction image IM1 corresponding to the first depth D1 is generated. Similarly, the eddy current induction measurement further includes a second eddy current induction measurement; wherein the second eddy current induction measurement corresponds to a second transmission frequency to generate a second eddy current induction image IM2 corresponding to a second depth D2, wherein the imaging unit 122 forms a depth image DM with depth values ​​based on the first eddy current induction image IM1 and the second eddy current induction image IM2. Eddy current induction images IM1-IMx corresponding to different depths can be generated through eddy current induction measurements at different transmission frequencies. The imaging unit 122 can superimpose the eddy current induction images IM1-IMx corresponding to different depths D1-Dx by overlay operation to generate a depth image DM with depth values. Depth imaging (DM) allows operators to more clearly understand the differences between obvious and inconspicuous eddy current generation areas, as well as their three-dimensional structure. It aids in understanding the anatomical location of obvious eddy current generation areas and facilitates explanation to non-medical personnel. It should be noted that this invention does not limit the relationship between the first and second transmission frequencies; multiple eddy current induction measurements can be performed from low depth to high depth or from high depth to low depth.

[0043] In one embodiment, referring to FIG3, each of the plurality of coils 111 has a first coil unit 1111 and a second coil unit 1112, the center of the first coil unit 1111 and the center of the second coil unit 1112 overlapping each other. Specifically, when performing multiple eddy current induction measurements at different emission frequencies, different emission frequencies of excitation electromagnetic signals can be emitted by switching the first coil unit 1111 and the second coil unit 1112. For example, the first coil unit 1111 and the second coil unit 1112 have different inductance values ​​or resonant frequencies, and will generate different excitation electromagnetic signals after being excited by the same AC signal. Because the center of the first coil unit 1111 and the center of the second coil unit 1112 overlap each other, the excitation electromagnetic signals they generate will act on the same range but correspond to different depths. By switching multiple coil units, eddy current induction images IM1-IMx corresponding to different depths are generated. In one embodiment, the number of corresponding depths can be increased by overlapping the multiple coil units 1111-111y. For example, the first coil unit 1111 and the second coil unit 1112 can be measured simultaneously, so the corresponding depth will be between the depth of using the first coil unit 1111 alone and the depth of using the second coil unit 1112 alone, but the choice of coil units is not limited to this. Therefore, multiple depths D1-Dx (i.e., y is less than x) can be corresponded to by fewer coil units 1111-111y. It should be noted that the first coil unit 1111 and the second coil unit 1112 are not limited to the concentric circles shown in FIG3. The first coil unit 1111 and the second coil unit 1112 can also be a three-dimensional overlapping structure with different materials or other means to generate different inductance values ​​or resonant frequencies. In this embodiment, referring to Figure 4, the control module 120 preferably includes a coil selection unit 123. The coil selection unit 123 is used to select one of the first coil unit 1111 and the second coil unit 1112 for eddy current induction measurement. Specifically, the coil selection unit 123 is a circuit element such as a switch, multiplexer, or selector. The coil selection unit 123 can select the coil through a selection signal. It should be noted that Figures 3 and 4 are used for illustration with only two coil units for simplicity. As those skilled in the art will know, there can be two or more coil units, and the coil selection unit 123 can have a switching quantity corresponding to the number of coil units.

[0044] In one embodiment, referring to FIG5A, the control module 120 further includes a transmission frequency selection unit 124. The transmission frequency selection unit 124 is used to select the transmission frequency when the eddy current measurement unit 121 drives the complex coils 111 to perform eddy current induction measurement. The transmission frequency selection unit 124 can adjust the transmission frequency during eddy current induction measurement to correspond to different depths. When the transmission frequency selection unit 124 can select a higher transmission frequency, the axial resolution of the depth image with depth value will also increase, reducing problems such as ghosting or misjudgment caused by insufficient eddy current induction image IM superimposed on the depth image.

[0045] The selection mechanism of the transmission frequency selection unit 124 can be seen, for example, with reference to FIG5B. The transmission frequency selection unit 124 can select the transmission frequency when the eddy current measurement unit 121 drives the complex coils 111 to perform eddy current induction measurement by changing the excitation signal of the eddy current measurement unit 121. For example, the eddy current measurement unit 121 has multiple excitation signals AS1-ASx. The excitation signals AS1-ASx cause the complex coils 111 to emit excitation electromagnetic signals ES1-ESx with different transmission frequencies. The transmission frequency selection unit 124 can select the excitation signal corresponding to the depth requirement from the excitation signals AS1-ASx according to the depth requirement. This allows multiple eddy current induction measurements corresponding to different depths to generate a depth image with depth values. By adjusting the excitation signals AS1-ASx, more and more accurate depth adjustments can be provided, thereby improving the quality of the depth image.

[0046] On the other hand, the selection mechanism of the transmission frequency selection unit 124 can be seen, for example, in FIG5C. The transmission frequency selection unit 124 includes an adjustable passive element array PA, which is coupled to a complex coil 111 to adjust the AC characteristics of the complex coil 111. Specifically, the adjustable passive element array PA can change the resonant frequency of the LC circuit composed of the coil and the capacitor. Taking FIG5C as an example, the adjustable passive element array PA can be a variable capacitor corresponding to the complex capacitance values ​​C1-Cx, but is not limited to this. Any passive element that can adjust the resonant frequency of the LC circuit of the coil should be within the scope of this embodiment. By using the adjustable passive element array PA, the excitation signal of the eddy current measurement unit 121 can be adjusted by hardware, thereby simplifying the circuit and adjusting the frequency of the excitation electromagnetic signal without the need for precise signal generation and signal frequency control means.

[0047] In one embodiment, referring to FIG6A, the control module 120 further includes a channel selection unit 125, which is coupled to the coil array 110 and used to select at least one of the multiple coils 111 to be coupled to the eddy current measurement unit 121 for eddy current induction measurement. The channel selection unit 125 is, for example, a multiplexer, selector, switch, or transistor, or other switching control element. The channel selection unit 125 can connect the portion of the multiple coils 111 to be measured for eddy current induction to the eddy current measurement unit 121 to receive the excitation signal. The number of coils to be measured in a single eddy current induction measurement can be reduced through the channel selection unit 125. This simplifies the circuit and reduces the emitted electromagnetic wave energy. Segmented induction further reduces interference between coils. For example, coils that are far apart can be measured for eddy current induction simultaneously. When eddy current is generated, the measurement results are not affected by interference between the coils because they are far apart. On the other hand, the channel selection unit 125 can also enable the multiple coils 111 to perform eddy current induction measurement in a group manner. This can achieve the purpose of scanning or sensing one by one. However, the purpose of providing the channel selection unit 125 in this invention is not limited to this.

[0048] In an embodiment of the channel selection unit 125, the channel selection unit 125 may include a first direction selection unit 1251 and a second direction selection unit 1252. Specifically, referring to FIG6B, the channel selection unit 125 may have, for example, a first direction selection unit 1251 corresponding to the row direction of the coil array 110 and a second direction selection unit 1252 corresponding to the column direction of the coil array 110. The first direction selection unit 1251 and the second direction selection unit 1252 provide specific coil positions for activation to achieve better selection and control. Furthermore, using the first direction selection unit 1251 and the second direction selection unit 1252 can effectively reduce the number of channels required by the first direction selection unit 1251 and the second direction selection unit 1252. Therefore, components with fewer channels can be selected to achieve the purpose of the channel selection unit 125 controlling multiple coils 111.

[0049] It should be noted that the coil array is not limited to the planar array form shown in FIG1. ​​For example, referring to FIG7, the non-planar coil array 210 can be formed by placing multiple coils 111 on the test area (e.g., breast skin). In this embodiment, the eddy current induction image IM is not limited to a planar image. For example, as shown in FIG7, the eddy current induction image IM can be an image attached to different depth layers of the test area. A three-dimensional image of the test area can be superimposed through the eddy current induction images IM corresponding to different depth layers. For this purpose, the relative positions of the multiple coils 111 on the surface of the test area can be specifically located, for example, through various shape capture or locator methods. By the relative positions of the multiple coils 111 and the corresponding eddy current induction measurements at different depths, images of different depth layers of the test area and a three-dimensional image of the test area can be generated.

[0050] In another embodiment of the coil array, the coil array can be a ring array. Specifically, referring to FIG8, a plurality of coils 111 are arranged sequentially into a ring coil array 310. The plurality of coils 111 in the ring coil array 310 can perform eddy current induction measurement on the test part located in the middle of the ring. This obtains images of different depth layers of the test part. It should be noted that the present invention is not limited to the number of rings in the ring coil array 310. For example, the ring coil array 310 can be formed into a columnar ring array by a plurality of ring groups 311-31x. Through the columnar ring array, columnar images of different depth layers of the test part can be obtained. Furthermore, the plurality of ring groups 311-31x can be measured simultaneously or at different times, thereby achieving scanning or similar effects. In one embodiment of the ring coil array 310, the eddy current generation state or conductivity distribution (e.g., tumors or blood vessels) in the test part can be deduced by means of inverse problem or other methods using the measurement signals received by each of the plurality of coils 111. This allows for the direct acquisition of a three-dimensional image of the area to be tested.

[0051] In one embodiment, the eddy current measurement unit is further used to perform baseline correction measurement to obtain a baseline value; wherein the imaging unit corrects the eddy current induced image based on the baseline value. Specifically, before or after the eddy current induced measurement, the eddy current measurement unit can perform baseline correction measurement by emitting a reference electromagnetic signal through the coil array 110. In the baseline correction measurement, the measurement result of the reference electromagnetic signal is predictable or can be preset compared to the excitation electromagnetic signal. For example, the reference electromagnetic signal will not cause eddy current interaction in the area to be measured or will cause predictable interaction. Therefore, the baseline correction measurement can obtain a baseline value. Specifically, the state or quality of each object under test, environment, and / or coil array may cause a deviation in the eddy current induced measurement. By using the baseline correction measurement with predictable results, the degree of deviation between the current measurement result and the predicted baseline value can be known. By correcting this degree of deviation, the influence of external factors on each measurement can be effectively minimized. The imaging unit can also correct each generated eddy current induced image to the same baseline based on the baseline value to reduce imaging errors. It should be noted that the reference electromagnetic signal can be one or more different frequencies. For example, multiple sets of reference electromagnetic signals can be used to correct within the reference range. Therefore, in addition to the offset baseline, the baseline scaling ratio can also be used to correct the baseline scaling ratio.

[0052] The imaging device proposed in this invention can be used, for example, for physiological monitoring. By using a coil to emit an excitation electromagnetic signal, eddy currents are induced in areas of different impedance, such as tumors, blood vessels, or organs, at the site of measurement. The generation of these eddy currents varies due to differences in impedance or conductivity at the site of measurement caused by various physiological states (e.g., pulse or tumor formation). These differing eddy currents cause the coil to receive different feedback electromagnetic signals, and the measurement results are imaged through the processing of the imaging unit. The imaging device using eddy current induction can achieve non-contact operation without any coupling agent. Furthermore, eddy current induction can reach different depths depending on the emitted electromagnetic signal, thereby enabling imaging of targets at different depths. In terms of cost, the coil and control circuit can be implemented using various mature circuit manufacturing technologies, effectively controlling costs compared to ultrasound probes. Therefore, the imaging device of this invention is advantageous for application in personal care or long-term and / or real-time monitoring.

[0053] The prior description of the invention is provided to enable those skilled in the art to make or practice the invention. Various modifications to the invention will be apparent to those skilled in the art, and the general principles defined herein can be applied to other variations or embodiments can be combined with or implemented individually without departing from the spirit or scope of the invention. Therefore, the invention is not intended to be limited to the examples described herein, but is accorded the widest scope consistent with the principles and novel features of the invention herein. [Simplified Explanation of the Diagram]

[0021] The accompanying drawings presented in this invention are intended to help describe various embodiments of the invention. However, to simplify the drawings and / or highlight what the drawings are intended to present, known structures and / or elements in the drawings may be drawn in a simple schematic manner or presented in an omitted manner. On the other hand, the number of elements in the drawings may be singular or plural. The accompanying drawings presented in this invention are only for illustrating these embodiments and not for limiting them.

[0022] Figure 1 is a schematic diagram of an imaging device in one embodiment of the present invention.

[0023] Figure 2 is a schematic diagram of forming a depth image in one embodiment of the present invention.

[0024] Figure 3 is a schematic diagram of a coil having a first coil unit and a second coil unit in one embodiment of the present invention.

[0025] Figure 4 is a schematic diagram of a control module including a coil selection unit in one embodiment of the present invention.

[0026] Figure 5A is a schematic diagram of a control module including a transmission frequency selection unit in one embodiment of the present invention.

[0027] Figure 5B is a circuit diagram of changing the coil emission frequency through a complex excitation signal in one embodiment of the present invention.

[0028] Figure 5C is a circuit diagram of changing the coil emission frequency through an adjustable passive element array in one embodiment of the present invention.

[0029] Figures 6A and 6B are schematic diagrams of a control module including a channel selection unit in one embodiment of the present invention.

[0030] Figure 7 is a schematic diagram of the implementation of a non-planar coil array in one embodiment of the present invention.

[0031] Figure 8 is a schematic diagram of the implementation of the ring coil array in one embodiment of the present invention.

Claims

1. A vascular imaging device, comprising: a coil array disposed outside a measurement location and including a plurality of coils; and a control module coupled to the coil array and including: An eddy current measurement unit is configured to drive the complex coils to perform an eddy current induction measurement at the measured location to obtain multiple eddy current measurement results corresponding to the complex coils; an imaging unit is configured to form a blood vessel image of at least one blood vessel at the measured location based on the multiple eddy current measurement results and the coordinate position of each coil of the complex coils; and a transmission frequency selection unit is configured to select the transmission frequency when the eddy current measurement unit drives the complex coils to perform the eddy current induction measurement; wherein the eddy current induction measurement includes a first eddy current induction measurement and a second eddy current induction measurement; wherein the first eddy current induction measurement corresponds to a first transmission frequency to generate a first blood vessel image corresponding to a first depth, and the second eddy current induction measurement corresponds to a second transmission frequency to generate a second blood vessel image corresponding to a second depth; and wherein the imaging unit forms a depth image with depth values ​​based on the first blood vessel image and the second blood vessel image.

2. A vascular imaging device, comprising: a coil array disposed outside a measurement location and including a plurality of coils; and a control module coupled to the coil array and including: An eddy current measurement unit is used to drive the complex coils to perform an eddy current induction measurement on the measured location to obtain multiple eddy current measurement results corresponding to the complex coils; and an imaging unit is used to form a vascular image of at least one blood vessel in the measured location based on the multiple eddy current measurement results and the coordinate position of each coil of the complex coils; wherein the eddy current induction measurement includes a first eddy current induction measurement and a second eddy current induction measurement; wherein the first eddy current induction measurement corresponds to a first transmission frequency to generate a first vascular image corresponding to a first depth, and the second eddy current induction measurement corresponds to a second transmission frequency to generate a second vascular image corresponding to a second depth; wherein the imaging unit forms a depth image with depth values ​​based on the first vascular image and the second vascular image; and wherein the coil array includes a biocompatible material layer covering the complex coils.

3. The vascular imaging apparatus as claimed in claim 1 or 2, wherein each of the plurality of coils has a first coil unit and a second coil unit, the center of the first coil unit and the center of the second coil unit overlapping each other.

4. The vascular imaging apparatus of claim 3, wherein the control module further includes a coil selection unit for selecting one of the first coil unit and the second coil unit for the eddy current induction measurement.

5. The vascular imaging apparatus of claim 2, wherein the control module further includes a transmission frequency selection unit for selecting the transmission frequency at which the eddy current measurement unit drives the complex coils to perform the eddy current induction measurement.

6. The vascular imaging apparatus as claimed in claim 1 or 5, wherein the transmit frequency selection unit includes an adjustable passive element array coupled to the complex coils to adjust the AC characteristics of the complex coils.

7. The vascular imaging apparatus as claimed in claim 1 or 2, wherein the control module further includes a channel selection unit coupled to the coil array and used to select at least one of the plurality of coils to be coupled to the eddy current measurement unit for performing the eddy current induction measurement.

8. The vascular imaging apparatus of claim 7, wherein the channel selection unit includes a first direction selection unit and a second direction selection unit.

9. The vascular imaging apparatus as claimed in claim 1 or 2, wherein each of the plurality of coils corresponds to a pixel coordinate on the vascular image.

10. The vascular imaging apparatus as claimed in claim 1 or 2, wherein the coil array is a ring array.

11. The vascular imaging apparatus of claim 1 or 2, wherein the eddy current measurement unit is further configured to perform a baseline correction measurement to obtain a baseline value; wherein the imaging unit corrects the vascular image based on the baseline value.

12. The vascular imaging device as claimed in claim 2 or 5, wherein the biocompatible material is selected from polydimethylsiloxane (PDMS), SEBS, or biocompatible silicone.

Images