KR100752334B1 - 2 dimensional curved array transducer for use in ultrasound imaging apparatus - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to two-dimensional array transducers used in three- to four-dimensional ultrasound image forming systems, wherein the transducers are disposed on curved surfaces having one or more curvatures. The 2D surface array transducer includes N × M transducers, and N and M are determined according to the view angle and volume angle of the 3D ultrasound image that can be formed using the surface array transducer. do. In order to control the two-dimensional curved array transducer, there is further provided high voltage switching elements for switching the thermal transducers, and a switching controller for controlling the switching elements to short any of the array transducers. .

Description

Two-Dimensional Surface Array Transducer for Ultrasound Imaging Apparatus {2 DIMENSIONAL CURVED ARRAY TRANSDUCER FOR USE IN ULTRASOUND IMAGING APPARATUS}

1A is a three-dimensional view of a sphere with a two-dimensional curved array transducer disposed on a surface thereof.

FIG. 1B is a sectional view from above of the sphere of FIG. 1A; FIG.

1C is a cross-sectional side view of the sphere of FIG. 1A;

FIG. 1D illustrates a case where a two-dimensional curved array transducer is located on a curved surface having two curvatures. FIG.

2 is a front view showing the structure of a two-dimensional surface array transducer;

3 shows an example of folding the array elements in the elevation direction.

4 is a diagram schematically illustrating the application of the high-direction folding to the bundle of the two-dimensional array conversion element according to the second embodiment.

5 shows an example of folding the array elements in the lateral direction.

FIG. 6 is a view illustrating the folding of the two-dimensional array converter according to the third embodiment in both lateral and altitude directions.

FIG. 7 is a view illustrating the folding of the two-dimensional array converter according to the third exemplary embodiment in which folding is applied in both lateral and altitude directions. FIG.

8 is a diagram illustrating an ultrasound image forming system using the 2D curved array transducer of the present invention.

9 illustrates a connection relationship between a transducer, a transmission transistor, and cross point switches according to another exemplary embodiment of the present invention.

10 is an example of a circuit of the receiving buffer and cross point switch block 110 of FIG.

<Explanation of symbols for main parts of the drawings>

1: input unit

5: switching control unit

11: pulsar

21: transmit and receive switch

31: receiving unit

37: beam forming portion

Until now, the general ultrasonic diagnostic apparatus provided a two-dimensional cross-sectional image of the inside of a human body using a one-dimensional array transducer. Recently, a method of using a two-dimensional array transducer has been attempted to obtain a three-dimensional (or four-dimensional) image. However, in this case, the number of channels increases exponentially than the case of using the one-dimensional array transformer, and there are many limitations with the current technology in the actual system implementation. For example, a general concept two-dimensional transducer that extends a conventional phased array transducer that can be deflected in two dimensions to obtain a three-dimensional (or four-dimensional) image is the number of channels that grow exponentially. (For example, if you extend a 64-channel one-dimensional phased array transformer to a two-dimensional phased array transformer, the number of channels is 64x64 = 4096). Even if a large system is implemented using an integrated circuit, a large amount of electric wires connected from the system main body to a probe including a transducer are heavy and inconvenient for the operator to use for diagnosis, which leads to an unreasonable situation. If the current channel is limited to the number of channels (for example, 256 or 512) that can be implemented in order to solve this situation, the resolution will be drastically reduced.

In addition, these two-dimensional phased array transformers require beam steering to obtain each scan line, in which case the spacing between the array transducer elements is 0.5 to avoid unwanted grating lobes. It should be limited to less than [lambda] [wave length]. Therefore, this limits the size of the entire array transformer and causes resolution degradation.

Another way to obtain a three-dimensional (or four-dimensional) image is to move the existing one-dimensional array transducer mechanically (in high or frame advancing directions) instead of using the two-dimensional array transformers mentioned above. ) There is a way to get the image. However, in this method, it is necessary to know the exact position information of the mechanically moving one-dimensional array transducer, which requires the accurate adjustment using a motor. Also, in this case, since the one-dimensional array transducer is simply moved in the altitude direction or the frame advancing direction, the altitude resolution is still limited by the acoustic lens as in the case of using the conventional one-dimensional array transducer. That is, since the one-dimensional array transducer is used, the beam can be focused where desired by applying a different time delay for each conversion element in the lateral direction, but in the altitude direction, only the focusing effect by the lens is obtained. That is, the method of mechanically moving the one-dimensional array transducer to obtain a three-dimensional (or four-dimensional) image cannot overcome the degradation of the high resolution of the conventional one-dimensional array transducer, and it is difficult to accurately control the array transducer mechanically. This and at the same time inevitably wear on the machine parts can shorten the service life of the product and cause many usage problems.

Accordingly, an object of the present invention is to provide a two-dimensional surface array transducer of a novel structure that can be implemented by the current technology without a significant loss of resolution.

It is another object of the present invention to provide an ultrasound image forming apparatus including the 2D curved array transducer.

It is still another object of the present invention to provide a bar-up for reducing the amount of computation required for image formation in an ultrasonic image forming apparatus including the 2D curved array transducer.

In order to achieve the above object, a two-dimensional curved array transducer for an ultrasound imaging apparatus is provided, wherein the transducers are arranged on a curved surface having at least one curvature.

The curved array transducer includes N × M transformers, and N and M are determined according to a view angle and a volume angle of a 3D ultrasound image that may be formed using the curved array transducer. The curved surface may be a spherical surface.

In addition, a high voltage switching element for switching the array transducers is attached to the two-dimensional curved array transducer of the present invention, and a switching controller for controlling the switching elements to short-circuit any of the array transducers. It is provided.

The biggest problem of the conventional one-dimensional phased array transducer is that the scanning line must be obtained by deflection of the beam. When a scanning line is obtained by deflecting a beam like a phased array transducer, a grating-lobe may occur, and the spacing of array elements is necessarily limited to 0.5 lambda or less to avoid this. In the case of the one-dimensional surface array transformer (convex or concave array transformer), there is no such restriction, and thus the array transformer spacing can be extended to be larger than λ. Theoretically, for curved array transducers that do not deflect the beam, the spacing of array elements should be less than [lambda] in order not to cause unwanted grating-lobes. However, this is for the case of continuous wave (CW), which is alleviated to some extent in real-world situations using wide-band pulses. Therefore, in practice, many surface array transducers designed with intervals of λ or more are used.

The curved array transducers, which can obtain scan lines by simple linear scan without deflection, can theoretically be twice as large as the linear array transducers because the size and spacing of the array elements are theoretically larger. Improvement in resolution and signal-to-noise ratio (SNR) can be expected.

The present invention relates to a two-dimensional surface array transducer having a new structure as shown in FIGS. 1 and 2 and an ultrasonic imaging system including the same, implemented to have such characteristics. That is, the present invention relates to a two-dimensional curved array transducer, which allows the advantages of the existing one-dimensional curved array transducer to be applied to two-dimensional, three-dimensional, and four-dimensional ultrasound imaging systems as they are. Two-dimensional curved arrays are suitable for the abdomen because both the far field and near field of view are adequately wide.

Figure 1 shows a three-dimensional top view and a cross-sectional view from above and from the side of a virtual sphere in which a two-dimensional curved array transducer according to the present invention is disposed on a surface. FIG. 1A is a three-dimensional view of a sphere in which a two-dimensional curved array transducer is disposed on a surface, in which R represents a radius of a sphere where two-dimensional conversion elements are located on a surface, and a and b are lateral directions (scanning lines). An array transducer is arranged in an area indicated by hatching on the surface of the sphere, showing the viewing angle in the direction in which the direction of travel) and the altitude direction (the direction in which the frame proceeds). If the two-dimensional curved conversion element is distributed on the spherical surface S as shown in Fig. 1A, R is the same in all the conversion elements. In this case, the scan line advancing direction and the frame advancing direction may be determined opposite to those shown in FIG. 1A.

FIG. 1B is a sectional view from above of the sphere of FIG. 1A; FIG. As shown in FIG. 1B, a determines the viewing angle provided in one frame. FIG. 1C is a cross-sectional view of FIG. 1A seen from the side. As shown in FIG. 1C, b determines the volume angle in the direction in which the frame proceeds. Depending on the design and purpose, a and b may be designed differently. That is, the two-dimensional surface transducer can be designed differently in width and height.

In addition, the variables R, a, and b may be different depending on whether the surface on which the conversion elements are located is a sphere as shown in FIGS. FIG. 1D illustrates a case in which two-dimensional curved array transducers are positioned on a donut-shaped surface having radii R1 and R2 at two vertices c1 and c2, respectively. In this case, R may be different for each transducer, and the roles of a and b are the same as in the case of a sphere, and may be the same as or different from each other.

FIG. 2 is a view showing a case where the two-dimensional curved array array located on the surface S of the sphere shown in FIG. 1A is viewed from the front surface where the beam propagates. N and M represent the total number of array elements in each of the side direction (a) in which the scan line moves and the altitude direction (b) in which the frame proceeds, and each N element that constitutes the actual active channel in each direction. ', M' (N> = N ', M> = M'). In addition, the size of each conversion element is represented by d and h. These values may be sufficiently changed according to the situation in which the ultrasonic diagnostic apparatus including the transducer is used, the diagnostic field, and the like.

In the case of using the two-dimensional curved array transducer as shown in FIG. 1, the two-dimensional opening of the conversion element corresponding to the predetermined scan line (that is, the transducer activated corresponding to the predetermined scan line) without having to deflect the beam when obtaining each scan line. Beams are sent to the focus point in the direction of the heading. Therefore, the greatest advantage of the one-dimensional curved array transducer can be maintained as it is. In other words, when the beam is deflected, the spacing of the array elements is limited (0.5λ), whereas in the two-dimensional curved array transducer of the present invention, the spacing between the converting elements can be extended to be λ or more, so that the size of the entire aperture is increased, so that the resolution is increased. And improvement of SNR is expected.

In addition, when using the two-dimensional curved array transducer of this structure, the transmission and reception delays for the active channels (active transducers) that are actually activated to obtain each corresponding scan line have a constant regularity in the scan line or frame progress direction. Have Therefore, by using this property, the control and image acquisition of the entire transducer can be easily and quickly performed using minimal hardware.

A practical embodiment using the two-dimensional curved array transducer of the present invention is described below. First, consider a two-dimensional curved array transducer having 64 array elements (that is, a total of 4096 conversion elements) on the x-axis and the y-axis, which are practically feasible. In this case, if the actual number of active channels is limited to 256, the 16x16 device group may be an opening by allocating 16 units on the x and y axes (see FIG. 2).

According to the structure of the two-dimensional curved array transducer of the present invention, not only the square opening but also the shape of the opening (X × Y) can be variously selected. The selection of the shape of the opening allows tradeoff between resolution and frame rate, and thus the choice of system performance is wide. That is, by using the X × Y opening in the most suitable form for each application or diagnostic purposes, it is possible to provide a variety of modes in the ultrasound imaging system using a single transducer.

According to the first embodiment of the present invention, 16x16 active channels are used as exemplified above. In this case, if the spacing of the array elements is the same, the resolution is reduced to 1/4 compared to the 64-channel system using the conventional 1-dimensional curved array transducer, but there is an advantage that the same resolution as the lateral direction can be obtained in the high-direction direction in the 2D image. . In this case, if a multi-beam receive focusing technique is applied in each of the scan line direction and the frame direction, a fast volume rate (volume / sec) can be obtained in a 3D or 4D ultrasound imaging apparatus. In other words, the use of the 16x16 aperture may result in some deterioration in image quality from the viewpoint of resolution, but this embodiment may be a suitable embodiment for a four-dimensional ultrasound imaging apparatus in which a volume rate is the most important factor.

According to the second embodiment of the present invention, 32 x 16 transducers are used as the active transducer set. However, in order to keep the number of channels (the number of channels to be controlled) the same as the case of 16 × 16, folding is performed using symmetry in the elevation direction. 3 illustrates a case in which the array elements are folded in the altitude direction, that is, the elements symmetric in the altitude direction are connected to each other. At this time, the connected or folded elements are transducers having symmetry with respect to a focal point or a scan line, and a pulse is transmitted simultaneously at the time of transmission, and is a pair of devices having the same delay value at the time of reception.

3 is a method of slightly increasing the resolution compared to the first embodiment while preventing the loss of the volume rate. In a 3D or 4D image field, a fast frame rate is a basic requirement, so a receive multi-beam function is required. According to the embodiment shown in FIG. 3, since the conversion elements placed in the lateral (x) direction are not folded, the multi-beams in the scan line traveling direction (x direction and lateral direction) can be realized, while the altitude direction Since the conversion elements located in (or the frame advancing direction) are folded, it is difficult to implement multiple beams in the frame direction. Instead, the volume rate may be maintained as it is by applying a frame interpolation technique.

In the second embodiment of the present invention, an opening in the form of a 32 x 16 element group is used, and the symmetrical folding shown in FIG. 3 is applied to the conversion elements in the frame advancing direction. In this case, since the symmetrical elements are folded, it is 32 × 8 channel in terms of calculation amount. Therefore, the calculation amount is the same as the embodiment of 16 × 16, but the lateral resolution and the SNR can be expected to be doubled.

In addition, increasing the spacing of the x-axis elements under acceptable grating lobe conditions (d = 1.5-2λ) can further increase the actual lateral resolution. In addition, compared to the case of the one-dimensional, since the electric focus in the altitude direction is possible, the actual overall resolution can be further improved.

Fig. 4 shows the form of a channel driven corresponding to any one scan line among the entire array elements according to the second embodiment of the present invention. In FIG. 4, the portion B is a block folded in the form of the portion A and the same as FIG. 3, and are symmetrically tied to each other in an altitude direction (frame progress direction).

The above-described embodiments are suitable for the case where the 2D curved array transducer of the present invention is used to acquire 3D or 4D ultrasound images. Even in an image forming apparatus using a 2D converter, a 2D image is often required to be provided as a basic function. The third embodiment is for acquiring a high resolution two-dimensional image by using the two-dimensional curved array transducer of the present invention. Obstetrics and gynecology is the most clinically applied diagnostic field for both 3D and 2D imaging. In this case, the frame rate of the 2D ultrasound image is not so prominent as compared to echocardiography. A single-beam receive focusing is sufficient without using When neither the altitude nor the lateral direction uses multiple beams, not only the folding in the altitude direction as shown in FIG. 3 but also the lateral folding using the lateral symmetry can be applied simultaneously, so that the system can be operated more efficiently. Fig. 5 shows the folding in the lateral direction, that is, the scanning line advancing direction. As in the above example, in the case of a system providing 256 channels, the system can actually process 64 x 16 active transducer groups, and the value of the 2D image is determined by this value. In this case, the value of 64 × 16 is a value considering bidirectional folding at 256 = 32 × 8, which is the actual number of channels that can be processed. Therefore, since the spacing between the array elements is greater than or equal to λ, the resolution of the conventional 64 channel system can be provided in the lateral direction and the focus of the 16 channels in the high direction increases the resolution of the overall 2D ultrasound image.

Fig. 6 shows the shape of the channel driven corresponding to any one scan line in the distribution of the entire two-dimensional array element in this situation. In FIG. 6, C, D, E, and F are blocks folded in the scan line advancing direction as shown in FIG. 5, while C, E, D, and F are symmetrically bound in the frame advancing direction as shown in FIG. Thus, a 256-channel system can be used to achieve the performance that a 1024-channel system can deliver.

7 is a modified embodiment of the folding method shown in FIG. 6 as a modified embodiment of the third embodiment. That is, the basic concept that the four blocks G, H, I, and J, which are symmetrical, are folded in the scan line advancing direction or the frame advancing direction, respectively, but have a different configuration of a group of transducers simultaneously included in the opening. to be. 7 shows that the distribution of the overall two-dimensional conversion element takes an elliptical shape. In this way, tradeoffs of lateral and altitude resolutions are possible by using various types of openings, thereby helping to construct an optimal ultrasound image. Can be.

By expanding the method of using the regularity of the delay value by folding up and down or left and right as described above, it is possible to group the transducer elements arranged in various forms into one channel. For example, in order to make the best use of the regularity of the delay values, all the transducers at the same point in time (or very similar distances) at a given focal point are found. Groups can be formed. Since one channel is simultaneously calculated during the beamforming operation, the larger the number of transducer elements grouped into one channel, the lower the complexity of the operation of the image forming system. As a method for using the regularity of the delay value in the case of using the 2D surface transducer, a method of combining 2, 4, and circular transform groups into a single channel has been described. In this way, the regularity of the delay value can be used to improve the performance of the system.                     

According to one embodiment of the present invention, multiple switches are placed on each transducer to implement folding (or multiple transducer channel formation). By controlling the switches connected to the transducers, it is possible to group arbitrary transducers into one group and short-circuit them.

1 illustrates some examples of the curved transducer according to the present invention, the curved transducer of the present invention is not limited thereto, and may include various types of curved transducers. For example, it is also possible to form transducers by arranging transducers on a cylindrical or conical surface. In this case, the above-described folding method should be selected according to the shape characteristics of the curved surface transducer. For example, curved transducers arranged on part of a cone do not have two-way symmetry, so only one-way folding is possible.

FIG. 8 is a diagram illustrating an embodiment of an ultrasound image forming system including a 2D curved array transducer of the present invention and implementing folding of the transducers using a switch. The pulser 11 is for outputting a bipolar pulse. The pulser 11 receives a binary sequence and converts an amplified signal so that a two-dimensional array transducer included in the input unit 1 can be driven. To serve.

A TX focus delay memory 14 stores a delay pattern of ultrasonic pulses to be transmitted into the human body through an array transducer and inputs the delay value to the pulser. The voltage of a predetermined magnitude, which is the output of the pulser 11, is applied at an appropriate time to each transducer according to the delay value, and as a result, ultrasonic pulses output from each transducer are transmitted into the human body. As a method of determining the transmission delay for each transducer 1, a fixed focusing technique for focusing the energy of the ultrasonic pulse to a predetermined point in the human body is mainly used. In recent years, attention has been paid to the use of synthetic aperture techniques or multiple focusing techniques to overcome the limitations of resolution caused by the use of fixed focusing techniques for dynamic focusing at each point of the object during reception. This has been increasing.

The input unit 1 comprises a two-dimensional curved array transducer and grouping switches attached to the transducers. The two-dimensional curved array transducer is composed of a plurality of elements and outputs ultrasonic pulses in response to the voltage input from the pulser 11. Of the array transformers that include multiple transformers, only some of them can be used in one transmission. For example 64 Even in an image forming apparatus including x64 transducers, 32 in a two-dimensional aperture in one transmission Only × 32 transducers can transmit ultrasound. Grouping switches attached to the transducer serve to group multiple transducers into one input channel.

The switching controller 5 supplies a control signal to the grouping switches included in the input unit. In an embodiment of the present invention the input and switching control 5 can be located inside the probe, or only the input can be located on the probe side and the switching control 5 can be on the main body side of the system.

The switch operates under the control of the switching control unit 5 so that a plurality of transducers form a group, and one group forms one channel. Therefore, the number of output signals from the input unit 1 to the transmission / reception switch 21 is not the number of transducers but the maximum number of channels. When the number of channels actually formed is smaller than the maximum number of channels, only signals of the actual channels are used for image formation at the rear end of the switch 21. The maximum number of channels may vary depending on how to group the transformers.

The switch 21 of FIG. 8 serves as a diplexer to prevent the high voltage power emitted from the pulser 11 from affecting the receiver. That is, when the converter alternately transmits and receives, it functions to switch the transmitter and receiver appropriately to the transducer.

The receiver 31 may include, for example, a pre-amplifier, a time gain compression (TGG) unit for correcting attenuation generated when ultrasonic waves pass through the body, and an analog-digital converter (ADC). Analog-to-digital converter), and amplifies the received signal into a digital signal.

The beam forming unit 37 performs the focusing with reference to the delay value from the reception focusing delay control section 36. The role of the beam forming unit 37 in the present invention is different from the conventional one or two-dimensional imaging system and the beam forming unit. In the present invention, when the array transducer of the input unit is an N × M two-dimensional curved array and the two-dimensional opening is N ′ × M ′, a plurality of transducer elements are grouped into one group by the action of the grouping switch. As a result, C × 1 A one-dimensional array or a two-dimensional array signal in the form of N ″ × M ″ is output from the transducer group, where C is the number of groups (or channels), where N ″ ≦ N ′ and M ′ ≦ M ″. Therefore, the beam forming unit 37 performs a role of adding and adding an appropriate delay to the one-dimensional or two-dimensional result data.                     

Since the number of transformers belonging to each group (or channel) may vary, the beam forming unit may perform a process of normalization that compensates the number of transformers included in a specific group before the signals of each channel are summed. This normalization may be performed by the receiver 31 or may be performed together with the normalization when calculating an apodization. To this end, the switching control unit 5 provides information on the number of elements in the channel to the receiver or apodization block (included in the beam forming unit, not shown). Alternatively, the normalization process may be omitted by adjusting the number of transformers belonging to the group so as not to change significantly (using the coarse transformer group described above).

The signal processor 41 performs envelope detection, log compression, and the like, and then converts the result data into a form for displaying on a display device as a 3D image. The image system shown in FIG. 8 may be used in various modes such as color Doppler, spectral Doppler, tissue characterization, as well as B mode data display.

In FIG. 8, although a large amount of computation is performed in a separate block, such as switching control and transmission / reception of connection delay, the processor performs most of operations required by one processor using a high speed processor having good computation performance. It is also possible. Also, by calculating the possible calculation results in advance and storing them in the memory, the LUT (Lookup Table) can be referred to.

A method of connecting a switch for controlling a 2D curved array transducer according to the present invention will be described. In one embodiment of the present invention, each switch element of the input unit may be attached with as many switches as the number of channels. In this case, however, the complexity of the switching circuit of the present invention is N × N × C _N , where N × N is the size of the array transformer and C _N is the number of independent signal channels in the N × N array transformer. For example, if a 64 × 64 array converter has 64 × 32 channels, each device requires 64 × 32 switches. Such a structure is possible when the integration degree of the switch circuit is very high, but it is also possible to implement other embodiments to reduce the complexity of the switching circuit in order to make the circuit more feasible and simple. C _N can vary greatly depending on how the folds are transformed and, if possible, the C _N value can be reduced by folding as many devices as one channel.

According to another embodiment of the present invention, the switches are connected in a hierarchical manner. In other words, you define blocks in the array transformer, group them together in a block first, and connect them to the parent block step by step. If the block size is called M × N and the total number of groups in a single block is C _M , then each device has C _M switches. Again, a switch for arbitrarily connecting M groups to C _N channels for each block is needed. Therefore, the total number of switches is (Switch × number of elements required for each element) + (Switch × number of blocks required for each block) = C _M × N × N + C _M × C _N × N × N / (M X M). In this way, the number of switches can be significantly reduced compared to the case where no hierarchical structure is used.

Modification of this embodiment can further reduce the number of switches by connecting the switches in a multilayer structure as well as a two-layer structure.

According to the present invention, various methods described below may be used as a method of manufacturing a transducer array including a switch for shorting and grouping transducers for each channel.

When the imaging system consists of a main body and a probe, it is more preferable in circuit design that the switch is located on the probe side. The probe is preferably light for convenience of diagnosis and for this purpose it is desirable to integrate the transducer and switch together on the wafer at the device level. Examples of processes similar to those for making such circuits include a manufacturing process of a capacitor micromachined ultrasonic transducer (CMUT) and an manufacturing process of an active mirror array (AMA). For example, US Pat. No. 5,682,260 discloses M × N actuator array below M A structure with an × N active matrix array is shown. The active matrix arrangement disclosed in this patent is similar to an analog switch in practical operation, and the actuator corresponds to the array transducer in the present invention. In other words, a semiconductor process similar to that disclosed in the above patent may be provided with a switch directly under the actuator (probe element in the present invention). However, in practice, the switch required for the current ultrasonic diagnostic apparatus can be a switch capable of withstanding a high voltage, and the switch in the patent may have a process difference in that it is usually for a low voltage (a few Vpp).

In the present invention, when only the grouping switch is integrated into the IC chip, the area of one switch (transistor) is approximately calculated in a 40 volt process, and the control unit and the wiring area (each occupying approximately 30% of the transistor area) are added to tens of thousands. Calculating the area of the integrated switch on the assumption that the switch is required for one ultrasound device, the area can be mounted in the probe of the ultrasound device. Although a low voltage switch (a switch that can be used when the transmit voltage is +20 or -20 volts) has been described with a relatively small area of the switch, the number of transducers to which the voltage is applied even when the transmit voltage is low is relatively higher than that of the two-dimensional processing apparatus. Since the ultrasonic power delivered to the diagnosis target increases, the influence of the low transmission voltage can be reduced. In particular, by using a coded pulse excitation method or the like, power delivered in spite of low voltage can be increased.

If it is not easy to simultaneously integrate the transducer and the switch at the chip manufacturing stage, it is also possible to use a flexible PCB to connect a large number of lines between the transducer element and the discrete component switch. .

In addition to the technology of integrating on a wafer basis, it is possible to make a circuit integrating a switch and a transducer using IC packaging technology which has been greatly improved in recent years. For example, it is preferable to use a packaging technique using a ball grid array (BGA). In other words, by treating the probe side and the switch with BGA, both can be directly coupled.

Alternatively, packaging size can be reduced by integrating switches and transducers using a packaging technology that directly attaches a semiconductor die to a printed circuit board without packaging. For example, by using a high density packaging technology such as flip chip packaging (FCP) or chip on film (COF) to package the converter and the switch integrated circuit of the present invention, The size of the associated circuit can be reduced.

Another embodiment of a circuit in which a switch for folding the transducer is configured connected to the transducer is shown in FIG. 9. In the circuit of Fig. 9, the transducer element has a separate transmitting transistor and also has a receiving buffer. Transmitting transistors may be somewhat larger in size for high voltages, but the size of the switching transistors and the transmitting transistors does not differ so much that it can be said to have a similar effect to the addition of one or two more switches. In this case, the transmitting transistor illustrated in FIG. 9 plays a role of a pulser in FIG. 8, that is, generates a high voltage pulse waveform and applies it to a device.

8 shows an embodiment in which switches for grouping transducers are directly connected to the array transducers, and transmission and reception are switched by the transmission / reception switch 21 for the entire input unit. 9 and 10 show another embodiment of implementing a folding switch, a transmitting / receiving switch 21 and a transmitting pulser. FIG. 10 shows a circuit including transmission transistors Tr1 and Tr2 and a voltage limiter for each transducer. The transmitting transistor serves to apply a +20 volt or -20 volt pulse to the transducer by turning on the same function as that of the pulser, that is, Tr1 or Tr2 in FIG. 8. During and before the transmission using Tr1 and Tr2, the receiving transistor Tr3 is turned off so that the high voltage for transmission does not affect the receiving end.

After a sufficient time after transmission, the receiving transistor Tr3 is turned on to transmit the received signal from the converter to the buffer and the cross point switch unit 110.

FIG. 10 shows an example of a circuit of the receiving buffer and the cross point switch block 110 in the case of the double beam. To ensure that the double beams do not affect each other, two buffers are connected to each translator. In the case of multiple beams, the number of buffers and the number of switch sets may increase. The transmission cross point switch block 120 is identical to the portion of the circuit of FIG. 10 except for the buffer and the beam 2 switch (not shown).

Although some embodiments of the present invention have been described so far, the present invention is not limited thereto, and various modifications and changes can be made without departing from the spirit of the present invention.

In the two-dimensional curved array transducer of the present invention, the size and spacing of the array elements can be larger than that of the linear array transducer, thereby increasing the size of the entire aperture, thereby improving resolution and improving signal-to-noise ratio (SNR). You can expect.

Applying the two-dimensional surface array transducer proposed in the present invention can be used in the most appropriate manner for diagnostic purposes by changing only the group configuration or switching control of the two-dimensional conversion elements without changing the hardware of the entire system, Utilization is increased.

Claims (5)

In the transducer probe used in the ultrasound image forming apparatus, A two-dimensional surface array transducer for an ultrasound imaging apparatus, the transducers being disposed on a curved surface having at least one curvature, A transducer probe comprising switching elements for folding the transducer having symmetry in at least one of the scan line travel direction and the frame travel direction. The method of claim 1, wherein the surface array transformer is N A transducer probe comprising x M transducers, wherein N and M are determined according to a view angle and a volume angle of a three-dimensional ultrasound image that can be formed using the curved array transducer. The transducer probe of claim 1 wherein said curved surface is a spherical surface. delete 2. The transducer probe of claim 1 further comprising a switching controller for controlling the switching elements to short circuit any of the array transducers.

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