JPH11276477A - Ultrasonic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology capable of performing two-frequency processing in a phasing system ultrasonic device to perform processing on a central frequency. SOLUTION: In an ultrasonic device having an ultrasonic wave transmitting/ receiving means composed of a plurality of ultrasonic oscillators to transmit/ receive an ultrasonic wave, a received wave phasing means to perform delay processing of a received signal, an adding means to add the received signal after the delay processing and a display means to successively display a received beam formed by the received wave phasing means and the adding means as an ultrasonic wave image, the received wave phasing means has a sampling means 103 to sample the received signal in a frequency of eight times a frequency of a transmitting signal, an eight-time delay processing means to perform delay processing on the received signal sampled by this sampling means 103 at a frequency interval of eight times the transmitting signal and a four-time delay processing means to perform delay processing on the received signal sampled by the sampling means 103 at a frequency interval of four times a frequency of the transmitting signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic device, and more particularly, to a technology effective when applied to a medical ultrasonic device using digital phasing using an analog-to-digital converter for digitizing an analog received signal. It is about.

[0002]

2. Description of the Related Art In a conventional ultrasonic apparatus, ultrasonic waves are transmitted to a subject by a plurality of ultrasonic transducers, and reflected waves from the inside of the subject are received by the same ultrasonic transducer. After amplifying the signal and electrically focusing the received signal from each transducer, that is, delaying (phasing) the wavefront from the focal point (received wave focus point) to align the phase of the received signal, , And added to form an ultrasonic beam. Also,
The receiving focus point was changed in multiple stages (dynamic) with time.

In a conventional ultrasonic apparatus, generally, FIG.
As shown in FIG. 5, the transducer array 110 is composed of 1 to a transducers, the distance from the (n + 1) th element as a reference element to the focus point P is r0, and the beam direction is θ. In this case, a propagation time difference τ0 occurs between the distance X0 from the first element to the focus point P and the distance r0 from the (n + 1) th element to the focus point P. For this reason, the reflected signal from the point P arrives earlier at the first element closer in distance than the (n + 1) th reference element.
The propagation time difference τ0 from the + 1st reference element is added to the signal received by the first element as a delay amount τ0.

Analog processing (so-called analog phasing)
Is performed, the above-described delay time is converted into tap switching data of the analog delay line.

On the other hand, in the case of performing digital processing, that is, in the case of digital phasing in which a received signal is converted from analog to digital to perform phasing, the way of giving a delay differs depending on the phasing method. The delay of the sampling interval (sampling delay) due to the read address of the memory from τ0 and the delay processing of the sampling interval or less are performed by the interpolation process. For example, in an electronic scanning ultrasonic diagnostic apparatus, an image for one frame is composed of about 100 to 300 rasters (number of beams to be scanned), and the raster performs dynamic reception focusing in the transmission direction. By forming and scanning its direction,
An image for one frame was formed.

In the ultrasonic imaging method, the sensitivity of the blood flow image is increased by injecting air bubbles or oily microbubbles of about several tens of μm into blood vessels, and the incident frequency of the microbubbles is increased. There has been a harmonic imaging method in which a reflected signal having a double emission frequency is received and the reflected signal is imaged to improve a blood flow image. In addition, even if a contrast material such as a microbubble is not inserted, a harmonic component of a reflected signal having a frequency twice as high as a transmission frequency (basic frequency) is imaged, that is, so-called non-linear imaging of a double frequency. Has also been active in recent years. In the imaging at the fundamental frequency and the double frequency, in analog phasing, the delay time is independent of the center frequency, so that the focus data was not changed. However, in the digital phasing, not only the sampling delay but also various devices (interpolation processing) for delaying a minute time smaller than the sampling time of the ADC are performed.
Many were functions of the center frequency.

FIG. 15 is a diagram for explaining a basic sampling method. In particular, FIG. 15A shows that an A / D converter (ADC) corresponding to each element samples with a common clock regardless of the wavefront. FIG. 9 is a diagram for explaining a method, in which a deviation from a wavefront (focus point) is corrected by interpolation processing. In particular, most of the processing is interpolation processing dependent on frequency. On the other hand, FIG. 15B is a diagram for explaining a method of sampling the ADC in accordance with the wavefront received from the focus point. This method has a multi-layered ADC sampling clock and realizes a minute delay equal to or less than a sampling period by selecting a sampling clock at which timing, and is called a wavefront synchronous sampling phasing method. In either method,
The coarse delay was realized by the difference between the addresses read from the written memory. Of course, the coarse delay accuracy was the sampling period. Sampling (quantization) methods include 4f0 sampling (quadrature sampling) and fixed sampling.

[0008]

SUMMARY OF THE INVENTION As a result of studying the above prior art, the present inventor has found the following problems. In the conventional ultrasonic apparatus, the center frequency f0 of the element is set as the transmission / reception frequency, and a so-called 90-degree sampling is performed to sample the reception signal at a frequency four times the center frequency, and the center frequency f0 is calculated from the sampled reception signal. In the ultrasonic apparatus that generates the image of (1), image processing at the double frequency cannot be performed.

On the other hand, the image generated from the received signal at the frequency f0 and the image generated from the received signal at the frequency 2f0 are images containing different information regardless of the use of the microbubbles described above. Therefore, an image having a frequency f0 and an image having a frequency 2f0, which are images having different frequencies, are generated from the same transmission signal.
It is desired to make a diagnosis based on three images.

However, in the conventional ultrasonic apparatus using digital phasing, as described above, phasing such as interpolation in the process of generating an image from a received signal is performed at the frequency f0 which is the center frequency of the element. Is used as a prerequisite for 90-degree sampling. Therefore, when an image with a frequency of 2f0 is to be generated by a conventional ultrasonic device, sampling of a received signal is 180-degree sampling, and An image of 2f0 could not be generated. That is, the conventional ultrasonic apparatus has a problem that it is not possible to perform two-frequency processing of the image of the center frequency and the image of the double frequency.

An object of the present invention is to provide a technique capable of performing two-frequency processing in a phasing type ultrasonic apparatus that performs processing in relation to a center frequency.

Another object of the present invention is to provide a technique capable of improving the diagnostic efficiency of an examiner such as a doctor.

Another object of the present invention is to provide a technique capable of improving the diagnostic accuracy of an examiner such as a doctor. The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0014]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows. (1) Ultrasonic transmitting / receiving means composed of a plurality of ultrasonic transducers for transmitting / receiving ultrasonic waves, wave phasing means for performing delay processing of a received signal, and addition for adding the received signal after the delay processing Means, and a display means for sequentially displaying a reception beam formed by the reception phasing means and the addition means as an ultrasonic image, wherein the reception phasing means comprises: Sampling means for sampling the reception signal at eight times the frequency of the transmission signal; eight-times delay processing means for delaying the reception signal sampled by the sampling means at eight times the frequency interval of the transmission signal; Means for delaying the received signal sampled by the means at a frequency interval four times as high as the frequency of the transmitted signal, and the receiving and phasing means by transmitting and receiving a single ultrasonic wave. And Addition means, forms reception beams of the frequency of the transmitting signal from the received signal after four times the delay process,
A reception beam having a double frequency is formed from the reception signal after the eight-fold delay processing.

(2) Ultrasound transmitting / receiving means composed of a plurality of ultrasonic transducers for transmitting / receiving ultrasonic waves, wave phasing means for performing delay processing of a received signal, and transmitting the received signal after the delay processing. In an ultrasonic apparatus having an adding means for adding, and a display means for sequentially displaying a reception beam formed by the reception phasing means and the addition means as an ultrasonic image, the reception phasing means is provided once. Means for forming an ultrasonic beam formed from the frequency of the transmitted signal from the received signal obtained by the above transmission and an ultrasonic beam formed from the doubled frequency.

(3) Ultrasound transmitting / receiving means comprising a plurality of ultrasonic transducers for transmitting / receiving ultrasonic waves, wave phasing means for delaying a received signal, and receiving a signal after the delay processing. In an ultrasonic apparatus, the ultrasonic transmission / reception unit includes an addition unit that performs addition, and a display unit that sequentially displays a reception beam formed by the reception phasing unit and the addition unit as an ultrasonic image. A transmitting means for transmitting a first transmission signal having a center frequency of the vibrator and a second transmission signal having a frequency different from that of the first transmission signal in one transmission in the same direction; I do.

According to the above-mentioned means (1), the sampling means samples the received signal at a sampling frequency 8f0 which is eight times the frequency (transmitted frequency) f0 of the transmitted signal, and thereby the transmission frequency ( It is possible to realize 90-degree sampling required when imaging a harmonic component of a reflected signal having a frequency twice as high as the fundamental frequency (double frequency 2f0).

Here, the eight-fold delay processing means delays the sampled reception signal at a frequency interval eight times that of the transmission signal, and the four-times delay processing means converts the sampled reception signal to the transmission signal. By performing delay processing at a frequency interval of four times the frequency, an ultrasonic image of the fundamental frequency f0 and the double frequency 2f0 is simultaneously formed in the same ultrasonic apparatus by one transmission and reception of ultrasonic waves and displayed on the display means. It becomes possible.

Therefore, an examiner such as a physician can easily compare and examine ultrasonic images having different reflection frequencies, thereby improving diagnostic efficiency.

In addition, an examiner such as a doctor can easily compare and examine ultrasonic images having different reflection frequencies.
Diagnosis accuracy can be improved.

According to the above-mentioned means (2), the beam forming means forms an ultrasonic beam formed from the frequency of the transmitted signal and a doubled frequency from the received signal obtained by one transmission. With the same ultrasonic apparatus, it is possible to form an ultrasonic image of the frequency of the transmitted signal and a double frequency at the same time in one transmission and reception of ultrasonic waves and display the same on the display means. It becomes possible.

Therefore, an examiner such as a physician can easily compare and examine ultrasonic images having different reflection frequencies, thereby improving diagnostic efficiency.

Also, an examiner such as a doctor can easily compare and examine ultrasonic images of different reflection frequencies.
Diagnosis accuracy can be improved.

According to the above-mentioned means (3), the transmitting means comprises a first transmitting signal having a center frequency of the ultrasonic vibrator and a second transmitting signal having a frequency different from the first transmitting signal. By transmitting the signal and the signal in the same direction in one transmission, only the frequency at the time of performing the delay processing of the reception phasing means is changed, and the center frequency and the double frequency (not due to nonlinearity, It is possible to obtain an ultrasonic beam (obtaining a beam close to the original double frequency transmission).

At this time, for example, an ultrasonic beam formed from the frequency of the first transmission signal from the reception signal obtained by one transmission to the reception phasing means and the frequency of the second transmission signal By providing a beam forming means for forming an ultrasonic beam formed from a single ultrasonic wave, the same ultrasonic apparatus can simultaneously generate a clear ultrasonic image of the frequency of the transmitted signal and the doubled frequency in one ultrasonic wave transmission / reception. It can be formed and displayed on the display means.

Therefore, an examiner such as a doctor can easily compare and examine ultrasonic images of different reflection frequencies, so that diagnostic efficiency can be further improved.

Also, an examiner such as a doctor can easily compare and examine ultrasonic images having different reflection frequencies.
The diagnostic accuracy can be further improved.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings together with embodiments (examples) of the invention. In all the drawings for describing the embodiments of the present invention, components having the same functions are denoted by the same reference numerals, and their repeated description will be omitted.

(Embodiment 1) FIG. 1 is a block diagram for explaining a schematic configuration of an ultrasonic apparatus according to Embodiment 1 of the present invention. Reference numeral 110 denotes a probe (ultrasonic transmission / reception means);
Denotes an element selection unit, 112 denotes a transmission phasing unit, 113 denotes a reception phasing unit (reception phasing unit), 102 denotes an addition unit, 105 denotes a signal processing unit, and 106 denotes a display unit.

In FIG. 1, the probe 110 includes, for example, a known ultrasonic vibrator (also referred to as an ultrasonic element; hereinafter, abbreviated as “element”) (where a is 2). These are well-known ultrasonic probes arranged in the above (natural numbers), and are connected to the element selection unit 111. Each element of the probe 110 generates an ultrasonic wave corresponding to the drive signal supplied via the element selection unit 111 and transmits the ultrasonic wave to a subject (not shown). Further, the ultrasonic wave reflected inside the subject, that is, in the living body, is converted into an electric signal and output to the wave receiving phasing unit 113 via the element selecting unit 111.

The element selection unit 111 is a selection unit including a well-known switching unit. Based on a control output from a control unit (not shown), the element selection unit 111 converts a drive signal output from the transmission phasing unit 112 into each of the probes 110. A system for transmitting to the elements and a system for transmitting the analog reception signal output from each element to the reception phasing unit 113 are switched.

The transmission phasing unit 112 uses the delay time difference for correcting the arrival time difference of the ultrasonic wave transmitted from each transducer to the transmission focus point based on the output of the control means (not shown). It is a well-known wave phasing means for generating and outputting a drive signal for driving each element of the element 110.

The wave receiving phasing section 113 is connected to each element one by one, and converts an analog received signal received by each element into a well-known A / D converter (hereinafter, “ADC”). (Hereinafter referred to as "received signal data")
That is, after converting to digital data, a delay process is performed to correct the arrival time difference between the reception signal and the reception focus point between the elements with respect to the reception signal received by each element,
Next, means for interpolating missing time associated with digital conversion by an ADC (not shown) will be described in detail later. However, the wave receiving and phasing unit 113 of the first embodiment performs sampling at a frequency eight times the center frequency of the element, that is, eight times the fundamental frequency (transmitting frequency) f0 of the transmitted signal, and a frequency four times the frequency 4f0 (so-called). , And delay processing of the eight-fold frequency 8f0 (so-called reception phasing at the double frequency 2f0). The details will be described later.

The addition means 102 is a well-known addition means for adding the interpolated reception signal data output from each of the a number of reception phasing sections 113 based on the control output of the control means (not shown). In the first embodiment, this is realized by a program that operates on an information processing device (not shown). That is, the adding means 102 outputs the frequency 4f0 after the interpolation processing and the phase alignment output from the wave reception phasing section 113.
Alternatively, phasing addition of the received signal data of 8f0 is performed, and received ultrasonic beams of respective frequencies are created from the received signal data.

The signal processing means 105 includes filtering,
After performing well-known image processing such as compression, edge enhancement, time-variable amplification, and scan conversion, the received signal data after the correction processing is converted into a video signal to be output to the display means 106. In the first embodiment, the signal processing unit 105 realizes the above-described image correction processing by a program operating on an information processing device (not shown), and it is well known that the received signal data after the image correction processing is converted into a video signal. Is realized by the video signal conversion means.

The display means 106 is a well-known display means.
For example, CRT (CathodeRay Tube)
A so-called color CRT display device using the same is used.

Next, the operation of the ultrasonic apparatus according to the first embodiment will be described with reference to FIG. 1. A converging beam is transmitted to the probe 110 selected by the element selecting section 111 by the transmission phasing section 112. Each element of the probe 110 is driven at the timing of forming, and emits ultrasonic waves to the subject. The ultrasonic echo from the subject, that is, the reflected ultrasonic wave is received by each element of the probe 110 and guided by the element selecting unit 111 to the wave receiving phasing unit 113 corresponding to the first to a-th elements. Then, a delay operation (phasing operation) is performed. The output from each of the wave receiving phasing units 113 is added by the adding means 102 to become a phasing addition output. This phasing addition output is output to the digital signal processor 105.
Is output to the display means 106 after the predetermined filter processing is performed, for example, by a tomographic image or CFM.
(Color flow mapping) The image is displayed in real time on the display screen.

Next, FIG. 2 is a diagram for explaining a schematic configuration of the wave receiving and phasing unit of the first embodiment, and FIG. 3 is a diagram illustrating a delay unit, an addition unit, and a signal processing unit of the first embodiment. FIGS. 2 and 3 are diagrams for explaining a schematic configuration of FIG.
The configuration of the ultrasonic apparatus according to the first embodiment will be described based on FIG. In particular, FIGS. 2 and 3 show one channel for simplifying the description.

2 and 3, reference numeral 100 denotes an ADC.
(Sampling means), 101 is delay means, 103 is sampling signal generation means, 104 is delay control means, 10
7 is a memory, 108 is 4f0 interpolation processing means (interpolation means,
4x delay processing means) and 109 are 8f0 interpolation processing means (interpolation means, 8x delay processing means). However, as shown in FIG. 2, in the first embodiment, each of the wave phasing units 113 is configured to include the ADC 100 and the delay unit 101.
And

The ADC 100 detects the probe 1 based on the sampling signal from the sampling signal generator 103.
A well-known A / D converter for converting an analog received signal input from each of the elements 10 into received signal data which is a digital received signal, and delaying the converted received signal data by delay means 101 to the memory 107.

The sampling signal generating means 103 is a means for generating a sampling signal having a frequency eight times as high as the center frequency of the element, that is, the transmission frequency f0, and supplying the sampling signal to the ADC 100. f0 4
This is the same as a sampling signal generating means for generating a sampling signal of double frequency.

The delay means 101 includes a memory 107 for temporarily storing the received signal data from the ADC, and a receiving signal data for every other received signal data stored in the memory 107. Readout At this time, a delay process for correcting the arrival time difference between the elements to the reception focus point is performed based on the readout address, and the missing time associated with the digital conversion by the ADC 100 at a frequency four times the center frequency, that is, at a frequency 4f0. It has a well-known 4f0 interpolation processing unit 108 that performs an interpolation process and outputs an interpolation output to the addition unit 102. Further, in the first embodiment, the delay unit 101 sequentially reads out the received signal data from the received signal data stored in the memory 107,
At this time, delay processing for correcting the arrival time difference between the elements to the reception focus point between the elements is performed, and interpolation of the missing time due to digital conversion by the ADC 100 is performed at a frequency eight times the center frequency, that is, at a frequency 8f0. It has a well-known 8f0 interpolation processing unit 109 that performs processing and outputs an interpolation output to the addition unit 102. However, the memory 107 has, for example, a well-known two-port SRA
The output read at a frequency of 8f0 using M is distributed as shown in FIG. Or, the memory 107
Also, when a well-known FIFO is used, the data is output at a frequency of 8f0 and distributed as shown in FIG. Further, the memories 107 may be provided in parallel.

The delay control means 104 is provided with write and read signals to and from the memory 107 of the delay means 101 and 4f.
This is a means for generating operation signals and the like of the 0 interpolation processing means 108 and the 8f0 interpolation processing means 109 and controlling the delay operation.

The adder means 102 outputs a number of 4f0
This is a well-known addition unit that adds the received signal data after the interpolation processing output from the interpolation processing unit 108 and the 8f0 interpolation processing unit 109. In the first embodiment, a program that operates on an information processing device (not shown) It is realized by. That is, the adding means 102 is
, And performs phasing addition of the received signal data after the interpolation processing and the phase alignment, and generates a received ultrasonic beam from the received signal data.

The signal processing unit 105 performs well-known image processing such as filtering, compression, edge enhancement, time variable amplification, and scan conversion on the output of the addition unit 102 connected to the 4f0 interpolation processing unit. Filtering, compression and edge enhancement are applied to the output of the 4f0 signal processing means 105a for converting the received signal data after the correction processing into a video signal for output to the display means and the addition means 102 connected to the 8f0 interpolation processing means. 8f0 signal processing means 105b for performing well-known image processing such as time-variable amplification and scan conversion, and then converting the received signal data after the correction processing into a video signal for output to a display means. In the first embodiment, the 4f0 signal processing means 1
05a and 8f0 signal processing means 105b are, for example,
Well-known DSP (Digital Signal Pro)
) or realized by a program operating on an information processing device (not shown), and the conversion of the received signal data after the image correction processing into a video signal is realized by a well-known video signal conversion means. I do.

First, a received signal received by each element of the probe 100 is converted by the ADC 100 into digital data (received signal data). At this time, the sampling frequency is set to eight times the fundamental frequency by the sampling signal generating means 103 and sampling is performed (conventionally, since only the fundamental frequency is imaged, the sampling frequency of the quadrature sample is four times the frequency). . The received signal converted into digital data, that is, received signal data, is subjected to delay processing by the delay unit 101. The phasing addition is performed by the adding unit 102, and various filtering processes such as detection, compression, and edge enhancement are performed by the signal processing unit 105.
After being converted into the display format, it is subjected to display interpolation processing and the like, and is displayed on the display screen of the display unit 106.

Next, FIG. 4 shows a time sequence of the ultrasonic apparatus according to the first embodiment, and the operation of the ultrasonic apparatus according to the first embodiment will be described below with reference to FIG. However,
FIG. 4 shows a case where synchronous sampling is performed as shown in FIG. 14A with the sampling clock being a common clock of each element of 8f0.

The received signal data sampled at the frequency 8f0 is first written into the memory 107 in the delay means 101. By reading from the memory 107, the data is read in parallel for the delay of the sampling interval and the processing of 4f0 and 8f0. The digital data (received signal data) stored in the memory 107 will be described, for example, as shown in FIG. 4, in a case where the digital data is written in order as D1, D2,. When reading this data, in order to reproduce the fundamental frequency f0, the 4f0 interpolation processing means 108 reads out the data every two clocks like the read data of the 4f0 processing to realize 4f0 samples (however, The sampling at this time is a quadruple frequency since the frequency f0 is read out every two samples, and is a 90-degree sample). In order to reproduce the double frequency 2f0, the 8f0 interpolation processing means 109
Like the read data of the 8f0 process, the data is read every sample clock to realize 8f0 samples (however, since the sampling at this time is 4 times the frequency of 2f0, it is a 90-degree sample). In the above description, for simplicity, the clock timing shows the data of the memory and the read data at the same time. However, it is natural that the clock is actually read out several minutes after the clock considering the delay time. is there. The outputs of the respective interpolation processing means 108 and 109 are input to the respective addition means 102 as they are in parallel, and are subjected to phasing addition by the addition means 102, and the respective outputs are output to the 4f0 signal processing means 1 respectively.
The signal is processed by the 05a or 8f0 signal processing means 105b and displayed on the display screen of the display means 106. At this time, for example, the two are combined to display an ultrasonic image of the fundamental frequency f0 on the left side of the display screen and an ultrasonic image of the double frequency 2f0 on the right side. As is clear from the above description, the ultrasonic apparatus according to the first embodiment has a configuration in which the fundamental and the double frequency can be simultaneously processed by one transmission.

As described above, in the ultrasonic apparatus according to the first embodiment, the center frequency of the element, that is, the transmission frequency f
This is necessary when the ADC 100 performs sampling of the received signal at the sampling frequency 8f0 that is eight times as large as 0 to image a harmonic component of the reflected signal that is twice the transmission frequency (basic frequency). 8f which realizes 90-degree sampling and sequentially uses the received signal data sampled by the ADC 100 to form an ultrasonic beam
0 interpolation processing means 109 and 8f0 signal processing means 105b
Delay processing to correct the arrival time difference between each element to the reception focus point, interpolation processing of missing time due to digital conversion by synchronous sampling, and filtering, compression, edge enhancement, time variable amplification, and scanning By performing well-known image processing such as conversion, a harmonic component of the reflected signal 2f0 having a frequency twice as high as the transmission frequency (fundamental frequency) f0 is imaged, and AD conversion is performed.
The 4f0 interpolation processing means 108 and 4f0 signal processing means 105a for forming an ultrasonic beam by using every other received signal data sampled at C100 to correct the arrival time difference between the elements to the received focus point. The transmission frequency (basic) is calculated by performing known delay time processing, interpolation processing for missing time due to digital conversion by synchronous sampling, and well-known image processing such as filtering, compression, edge enhancement, time variable amplification, and scan conversion. Since the reflection signal f0 of the frequency (f0) is imaged,
These two images can be simultaneously displayed on the display screen of the display means 106. Therefore, examiners such as doctors,
Since ultrasonic images having different reflection frequencies can be easily compared and examined, the diagnostic efficiency can be improved. In addition, an examiner such as a doctor can easily compare and examine ultrasonic images having different reflection frequencies, so that diagnostic accuracy can be improved.

(Embodiment 2) FIG. 5 is a view for explaining a schematic configuration of an ultrasonic apparatus according to Embodiment 2 of the present invention. In particular, FIG. Equipment 1
FIG. 5B is a diagram for explaining a schematic configuration of the reception phasing means for channels, and FIG.
FIG. 11 is a diagram showing an example of a four-phase clock supplied to the selection means 103a of FIG. However, the ultrasonic apparatus according to the second embodiment employs a method called wavefront synchronous sampling,
This is the f0 sample.

Therefore, in the ultrasonic apparatus according to the second embodiment, as is apparent from FIG. 5A, high-precision phasing is realized by the sampling clock shown in FIG. Therefore, the interpolation processing means 108 and 109 in the ultrasonic apparatus according to the first embodiment are not required. In other words, the delay means 101 of the second embodiment has a multi-phase sampling clock, which is a well-known technique, instead of the interpolation processing for the minute delay, and generates a clock that is shifted by a predetermined minute time from the reference sampling clock of the ADC 100. The selection unit 103a selects and samples the received signal with this clock, thereby realizing a small delay smaller than the sampling time interval with respect to the reference ultrasonic vibrator, and converting the sampled received signal. Memory 1
07, and the reception signal is delayed at the sampling interval. The sampling clock of the ADC 100 is generated by a well-known four-phase clock generator (not shown).
One of the phase clocks is supplied to the sampling signal generation means 10.
3 is provided by the selection unit 103a.
However, the period T of the four-phase clock in the second embodiment
Is T = 1 / (8f0), and the phase shift, that is, the shift of each clock is every ΔT time, and is synchronized with the wavefront of the received signal.

Next, based on FIG. 5B, FIG.
The operation of the wave phasing means 113 of the second embodiment shown in FIG.

The selecting section 103 a of the sampling signal generating means 103 selects a clock synchronized with the wavefront of the received signal from the four-phase clock, and applies the selected clock to the ADC 100. In this case, 4f0 is the basic, but sampling is performed at 8f0 in order to simultaneously process the fundamental frequency and the double frequency in one transmission. Therefore, ΔT = 1 / (32f
0). The received signal digitized by the sampling clock is temporarily stored in the memory 107, and then the received signal data of 4f0 and 8f0 are read out in parallel and adjusted by the adding means 102, as in the first embodiment. Signal processing means 1 in which phase addition is performed and the data is connected to each
05a and 105b, the signal processing is performed in parallel.
6 is displayed on the display screen.

In the same wavefront synchronizing sample, a method in which only the real part is processed without changing the RF, instead of the 4f0 sample (90 degree sample), that is, basically, the double frequency and the high frequency side of the band can be reproduced (the sampling theorem) Satisfaction) Sampling at sampling frequency, loading into memory, coarse delay, phasing and addition of all channels, and signal processing In the signal processing method, parallel processing is performed, and the fundamental frequency and the double frequency are separated by a band pass filter. By processing, both can be processed by one transmission.

As described above, in the ultrasonic apparatus according to the second embodiment, the period generated by the four-phase clock generating means (not shown) is T = 1 / (8f0), and the difference between the phases is ΔT = 1. The selection unit 103a of the sampling signal generation means 103 appropriately selects the four-phase clock of / (32f0),
By using the selected clock as the sampling clock of the ADC 100, the transmission frequency (basic frequency)
In addition to realizing the 90-degree sampling required for imaging the higher harmonic component of the reflected signal having a frequency twice as high as that of the reflected signal, the four-phase clock realizes high-precision phasing.
A known image processing such as filtering, compression, edge enhancement, time-variable amplification, and scan conversion is performed by the 8f0 signal processing unit 105b that forms an ultrasonic beam by sequentially using the received signal data, thereby transmitting the transmitted wave. A 4f0 signal for forming an ultrasonic beam by using the harmonic components of the reflected signal 2f0 having a frequency twice as high as the frequency (fundamental frequency) f0, and using every other received signal data sampled by the ADC 100. The processing unit 105a performs well-known image processing such as filtering, compression, edge enhancement, time-variable amplification, and scan conversion to image the reflected signal f0 at the transmission frequency (basic frequency) f0. One image can be displayed on the display screen of the display means 106 at the same time. Therefore, an examiner such as a doctor can easily compare and examine the ultrasonic images having different reflection frequencies, and can improve the diagnosis efficiency. In addition, since the examiner such as a doctor can easily compare and examine the ultrasonic images of different reflection frequencies,
Diagnosis accuracy can be improved.

(Embodiment 3) FIG. 6 is a view for explaining a schematic configuration of an ultrasonic apparatus according to Embodiment 3 of the present invention. In particular, FIG. Equipment 1
FIG. 6B is a diagram for explaining a schematic configuration of sampling signal generating means for channels, and FIG.
Is a diagram for explaining an example of the operation of the ultrasonic device,
FIG. 6C is a diagram for explaining another example of the operation of the ultrasonic apparatus according to the third embodiment. However, in FIG. 6, n indicates the number of rasters (ultrasonic beams).

However, the ultrasonic apparatus according to the third embodiment is
The other configuration is the same as that of the ultrasonic apparatus according to the first embodiment except that the configuration of the sampling signal generating means 103 for generating the sampling clock is different. Therefore, in the third embodiment, the sampling signal generating means 103 having a different configuration will be described in detail. Further, in the ultrasonic apparatuses according to the first and second embodiments, the output of the memory is basically processed in parallel by one transmission, so that the fundamental frequency and the double frequency are simultaneously processed. Embodiment 3 is different from Embodiment 3 in that a fundamental frequency and a double frequency are alternately processed by two transmissions without performing parallel processing.

As shown in FIG. 6A, the third embodiment
The sampling signal generating means 103b generates a clock having a frequency of 4f0 (a sampling frequency for generating an image having a frequency of f0) generated by a clock generating means (not shown) and a frequency of 8f0 (a sampling frequency for generating an image having a frequency of 2f0). ), A clock on a predetermined side is selected as a sampling clock, and ADC1 is selected.
Only the configuration of the selection unit 103b that outputs to 00 is different,
Other configurations are the same as those of the ultrasonic device according to the first embodiment.

Next, the operation of the ultrasonic apparatus according to the third embodiment will be described with reference to FIG. However, FIG.
(B) shows a case where the sampling frequency is measured for each raster in the beam direction of the ultrasonic beam.

As is clear from FIG. 6B, in this case, the ultrasonic apparatus of the third embodiment transmits ultrasonic waves twice for each raster,
In the second transmission, the selector 103b selects one of the frequencies 4f0 and 8f0 as a sampling clock, and
In the first transmission, the selection unit 103b selects the other side as a sampling clock. For example, in the first transmission of the first raster, the selecting unit 103b selects the frequency 4f0 as the sampling clock, and
(T11). In the next transmission, that is, the second transmission of the first raster, the selection unit 103b selects the frequency 8f0 as the sampling clock and supplies it to the ADC 100 (t12). Thereafter, in the first and second transmissions of each raster, the selection unit 103b supplies the sampling clock to the ADC 100 in the order described above, so that the frequency is a 90-degree sampling for creating an image of the basic frequency f0. Received signal data sampled at 4f0 and received signal data sampled at a frequency of 8f0, which is a 90-degree sampling for creating an image with a double frequency of 2f0, are stored in the memory 107.

The received signal data stored in the memory 107 is sequentially read out to the interpolation processing means for each raster as shown in FIG. Delay processing for correcting the arrival time difference is performed. Next, the interpolation processing means performs the interpolation processing of the missing time due to the digital conversion by synchronous sampling. At this time, in the third embodiment, in synchronization with the reading of the received signal data from the memory 107, the phasing frequencies supplied from the delay control means to the interpolation processing means are sequentially changed.
One of the frequency f0 and the frequency 2f0 is supplied. For example, in the first transmission of the first raster, the delay control means selects the frequency f0 as the phasing frequency and supplies it to the interpolation processing means (t11). In the next transmission, that is, the second transmission of the first raster, the delay control means selects the frequency 2f0 as the phasing frequency and supplies it to the interpolation processing means (t12). Thereafter, in the first and second transmissions of each raster, the delay control unit supplies the phasing frequencies to the interpolation processing unit in the order described above, thereby performing the interpolation processing of the missing time due to the digital conversion by the period sampling. It can be carried out. The received signal data after the interpolation processing is sequentially
After being added for the first and second transmissions of each raster,
By performing well-known image processing such as filtering, compression, edge enhancement, time-variable amplification, and scan conversion by the signal processing means, the transmission frequency f0 and the transmission frequency 2f0 are imaged. Is output to the display means. At this time, the display means superimposes and displays the display data of the frequency f0 and the frequency 2f0 for each raster as shown at t12 and t22 (for example, when a frame memory is provided, it corresponds to each raster of the frame memory). The two images can be displayed on the display screen of the display means 106 at the same time by writing the image data where the two display data are superimposed and displayed. Therefore, the same effect as in the first embodiment can be obtained. Of course, they may be displayed alternately, or may be displayed in separate areas.

In the above description, the sampling is sequentially performed with the clock of the frequency 4f0 and the clock of the frequency 8f0 for each raster. However, the ultrasonic apparatus according to the third embodiment is not limited to this. As shown in FIG. 6C, one frame may be continuously processed at the fundamental frequency f0, and the next frame may be processed at the double frequency 2f0.

Next, based on FIG. 6 (c), a sampling clock of frequency 4f0 and a frequency of 8f0
In the following, a case will be described in which the received signal is sampled sequentially with the sampling clocks of FIG.

As is apparent from FIG. 6C, in this case, in the ultrasonic apparatus according to the third embodiment, the selecting unit 103b samples one side of the frequencies 4f0 and 8f0 every frame. Select as clock. For example, in the first frame transmission, the selecting means 103b uses the frequency 4 as the sampling clock regardless of the raster number.
f0 is selected and supplied to the ADC 100 (t1 to tn).
In the transmission of the next frame, the second frame,
The selecting unit 103b uses the frequency 8 as the sampling clock.
f0 is selected and supplied to the ADC 100 (tn + 1 to t2).
n). Thereafter, in transmission of each frame, the selection unit 103
b, the sampling clock is set to ADC10 in the order described above.
0, the received signal data sampled at a frequency of 4f0, which is a 90-degree sampling for creating an image of the fundamental frequency f0, and a double frequency of 2f0
The received signal data sampled at a frequency of 8f0, which is a 90-degree sampling for creating an image, is stored in the memory 107.

The received signal data stored in the memory 107 is sequentially stored for each raster in the same manner as in the first embodiment.
Interpolation processing is performed by the interpolation processing means, and well-known image processing is performed by the signal processing means to form an ultrasonic beam. However, the delay control means also selects the frequency f0 as the phasing frequency and supplies it to the interpolation processing means during the transmission of the first frame in synchronization with the selection section 103b (t1 to tn). During the transmission of the second frame, the frequency 2f0 is selected as the phasing frequency and supplied to the interpolation processing means (tn + 1 to t2n). Thereafter, in this order, the delay control means sets the frequency f0, frequency 2
By supplying f0 to the interpolation processing means and the signal processing means, it is possible to generate an ultrasonic beam, that is, an ultrasonic image of a fundamental frequency (frequency f0) and a double frequency (frequency 2f0) for each frame.

In the display means, when the ultrasonic image output from the signal processing means is provided with, for example, a frame memory, the image data is written in a portion corresponding to each raster of the frame memory, thereby obtaining the frequency f0 and the frequency 2f0. Are superimposed, that is, two ultrasonic images can be simultaneously displayed on the display screen of the display means. Therefore, the same effect as in the first embodiment can be obtained. However, the display method is not limited to this.

In the third embodiment, the case where the present invention is applied to an ultrasonic apparatus of synchronous sampling has been described. However, the present invention is not limited to this. The sampling clock input to the selection unit 103b of the signal generation unit 103 is a 4-phase clock having a period of 1 / (4f0) and a 4-phase clock having a period of 1 / (8f0).
However, by selecting this clock at the timing shown in FIG. 6B or FIG. 6C and supplying it to the ADC 100, wavefront synchronous sampling can be realized. At this time, the above-described effect can be obtained by adding the signals sampled in each cycle in order and then processing the signals.

In the third embodiment, for example, as shown in FIG. 7, after the received signal is sampled by the ADC 100 and is a 90-degree sample, the complex signal converting means 701 is provided. When a complex signal is used and the phasing is performed by the memory 107 and the interpolation processing means 702, for example, the frequency 4f0 and the frequency 8f0
And the selector 103b outputs the clock of the third embodiment.
Similarly, the frequency 4f0 and the frequency 8f0 are selected for each transmission or one frame and output to the ADC 100, so that the ultrasonic beam of the fundamental frequency (frequency f0) and the double frequency (frequency 2f0), that is, the ultrasonic image, Since it can be generated, the present invention can be applied by the same method as in the above-described embodiment, and in this case, the above-described effects are also obtained. This interpolation method includes a complex phase rotation and a first latch 1105 of the latches shown in FIG.
And the third latch 1107 are removed, and a single filter interpolation method or the like can be applied.

As 8f0 samples, 4f0 samples are alternately obtained.
By processing using sample data and 8f0 sample data or performing parallel processing, an ultrasonic beam having a fundamental frequency and a double frequency can be generated by one transmission.

Further, in the case of simultaneous sampling at a fixed frequency other than the 90-degree sample, the received signal is
After sampling at 100, the received signal is
It is needless to say that the present invention can also be applied to a method of interpolating by performing filtering processing by interpolation processing means after coarse delay and performing interpolation.

(Embodiment 4) FIG. 8 is a diagram for explaining a schematic configuration of a delay unit, an addition unit, and a signal processing unit of the fourth embodiment, and FIG. FIG. 4 is a diagram for explaining a time sequence of an interpolation process. However, the frequency fs of the sampling signal in the ADC 100 shown in FIG. 8 is set to a frequency or higher that satisfies the double frequency sampling theorem.
The frequency is 8f0, which is a phasing frequency required for 90-degree sampling of the frequency (transmission frequency) f0 of the transmission signal. In the clock timing shown in FIG. 9, the storage of the received signal data in the memory 107 and the reading of the received signal data from the memory 107 are shown as the same time for the sake of simplicity. Is delayed by the number of clocks in consideration of the delay time. However, in general, the frequency f0 of the transmitted signal is made to coincide with the center frequency of each element of the probe 110, and hence the frequency of the transmitted signal is also described as the frequency f0 in the following description.

In the fourth embodiment, the schematic configuration of the ultrasonic wave receiver and the wave receiving phasing section 113 corresponding to each element is the same as the configuration shown in the first embodiment. In Section 4, only the portions having different configurations will be described.

In FIG. 8, reference numeral 801 denotes an interpolation processing means;
02 denotes f0 signal processing means, and 803 denotes f2 signal processing means. The f0 signal processing means 802 performs well-known signal processing on received signal data phased at the center frequency of the element, that is, the transmission frequency f0. The f2 signal processing means 803 is a means for performing well-known signal processing on received signal data that has been phased at a frequency 2f0 which is a multiple of the transmission frequency f0.

The interpolation processing means 801 performs delay processing (coarse delay processing) for correcting a difference in arrival time between each element to a reception focus point based on a read address when reading reception signal data stored in the memory 107. ) Is a means for performing delay processing (interpolation processing) associated with 90-degree sampling in a time series after sampling, and is realized by interpolation by well-known filtering or phase rotation by complex numbers.

Next, the operation of the interpolation processing means 801 according to the fourth embodiment will be described with reference to FIG. 9. As shown in the interpolation processing (1) to (3), the reception The reading of the signal data and the interpolation processing for each read received signal data can be divided into three types.

That is, as shown in interpolation processing (1) in FIG. 9, the received signal data sampled by the ADC 100 in the order of D1, D2,. The means 801 sequentially reads the received signal data, and alternately interpolates the read received signal data alternately in synchronization with the sampling clock to the frequency f0 of the reception phasing and the frequency 2f0 (frequency f0).
There is a first interpolation process for performing the interpolation process 2). Also,
As shown in the interpolation process (2) in FIG. 9, the ADC 100 samples the received signal data stored in the memory 107 in the order of D1, D2,. The received signal data is read out every other time, and the read-out received signal data is interpolated at the frequency f0 and the frequency 2f0 (frequency f2) in synchronization with the sampling clock. There are two interpolation processes. Further, as shown in the interpolation processing (3) in FIG.
With respect to the received signal data sampled in the order of 2,... And stored in the memory 107, the received signal data is read out at a period twice as long as the sampling clock, and at that period, the interpolation of the reception phasing frequency f0 is performed. There is a third interpolation process that eliminates the loss of the received signal data by performing the process and the interpolation process at the frequency 2f0 (frequency f2).

The received signal data delayed by the above-described interpolation processing is added by the adding means 102 and then subjected to well-known signal processing by the signal processing means 105.
However, in the signal processing means 105, the interpolation processing means 801
Signal processing means 8 corresponding to the reception phasing frequencies f0 and f2
02, 803.

As described above, in the present embodiment, the beam forming means is constituted by the interpolation processing means 801 and the adding means 102.

Next, FIG. 10 is a diagram for explaining the configuration of delay means for realizing the interpolation processing (1) shown in FIG. 9, and the following description will be made based on FIG. The operation of the ultrasonic device will be described. However, in FIG. 10, FIG. 10 (a) is a block diagram for explaining a schematic configuration of the delay means, and FIG. 10 (b) is a time sequence for explaining the operation thereof. FIG. 10 (a)
Is a general beat-down configuration.

In FIG. 10, reference numeral 1001 denotes a frequency moving unit, and 1002 denotes a filter. The frequency moving unit 1001 is a unit realized by a program operating on a known information processing apparatus. The received signal data sampled at a frequency fs equal to or higher than the sampling theorem of f0 is converted into a complex signal by the output thereof using a well-known complex mixing means, and is shifted to a low frequency (or zero frequency) to realize oversampling. This is a well-known frequency shifting means for shifting the sampling frequency to the lower frequency side. Further, the frequency shifting means 1001 of the present embodiment alternately converts the received signal data converted by the ADC 100 into the transmission frequencies f0 and 2f0, that is, cos, in synchronization with the sampling cycle.
(Ω ₀ t) (however, ω ₀ = 2πf ₀ ), sin (ω ₀ t)
And the multiplication of the received signal data, cos (ω ₂ t) (provided _{that, ω 2 = 2πf2 = 2π2f0)} , by alternating the multiplication of the sin (ω ₂ t), sampled at ADC100 receiving The wave signal data is alternately converted into received signal data M (f0) mixed at f0 and received signal data M (f2) mixed at f2.

The filter 1002 is connected to the frequency shifting means 10
01 is a well-known filter that removes and / or further decimates the sum frequency generated by mixing from the output of 01 to reduce the number of signals.

Next, the operation of the delay means according to the fourth embodiment will be described with reference to FIG. 10B. The received signal obtained by one transmission is sampled by the ADC 100 at the sampling frequency fs. Is done. Sck in FIG. 10B shows the sampling clock at this time. However, in the present embodiment, the reception phasing of the transmission frequency f0 and the double frequency 2f0 are performed based on the reception signal obtained by one transmission.
In this example, the sampling frequency fs of the ADC 100 is at least 4f0 or more. Received signal data R1, R2, sampled at frequency fs
R3... Are received by the frequency shifting means 1001 alternately with the reception signal data M1f0, M3f0... Mixed at the reception phasing frequency f0 and the reception signal data mixed at the reception phasing frequency f2. Wave signal data M2f2, M4f4
... However, as described above, the frequency shifting means 1001 of the present embodiment performs the frequency shift of the reception phasing frequency f0 for the reception signal data R1, R3,. Received signal data R2, R4,.
, The frequency of the reception phasing frequency f2 is shifted.

The received signal data output from the frequency shifting means 1001 is subjected to the sum frequency deletion by the filter 1002. In the case of the target component, that is, the odd-numbered received signal data, the received phasing frequency becomes f0. Wave signal data M
1 (f0), M3 (f0)... Are extracted, and in the case of even-numbered received signal data, received signal data M2 (f2), M4 (f2) whose received phasing frequency is f2. .. Are extracted and stored in the memory 107 as received signal data R1M1, R2M2,.

The received signal data R1M1, R2M2,... Stored in the memory 107 are sequentially read out by the interpolation processing means 801 in synchronization with the sampling clock Sck to perform a coarse delay. Interpolation processing is sequentially performed in time series at the reception phasing frequencies f0 and f2 of the wave signal data, and output to the addition means 102.

The adder 102 performs phasing addition of the received signal data from each element of the probe 110, and then outputs it to the signal processing means 802 and 803 corresponding to the received phasing frequency, and After the well-known signal processing is performed by the units 802 and 803, the image is displayed on the screen of the display unit 106.

In the fourth embodiment, the configuration in which the frequency shift is performed by the reception phasing at the transmission frequency f0 and the reception phasing at the double frequency 2f0 is not limited to this, and is not limited to three times. Needless to say, it may be a wave phasing of the frequency 3f0 or the quadruple frequency 4f0.

In the fourth embodiment, the interpolation processing is performed in time series. However, the present invention is not limited to this. For example, similar to the delay means of the first embodiment, It goes without saying that the interpolation processing means corresponding to the reception phasing frequency f0 and the interpolation processing means corresponding to the reception phasing frequency f2 may be provided and processed in parallel.

Also, instead of processing f0 and f2 (2f0) at the same time, processing is usually performed at f0, and when the examiner selects the double frequency mode, f2 processing may be performed by the same circuit. In this case, the mixing data and the interpolation data are data related to the selected center frequency. At this time, it goes without saying that the sampling frequency may be changed to a frequency suitable for f0 and a frequency suitable for f2.

The selection of the reception phasing frequencies f0 and f2 is as follows.
A filter 1002 is provided in parallel, and serial-parallel conversion is performed at the input.
It goes without saying that a configuration in which parallel-serial conversion is performed after the filter processing may be adopted.

Furthermore, in the fourth embodiment, the processing of the received signal data is performed by complex processing. However, the present invention is not limited to this. For example, only the real part processing is possible.

FIG. 11 is a diagram for explaining another configuration of the delay means for realizing the interpolation process (1) shown in FIG. 9. In particular, FIG. 11A shows an interpolation process using a filter. FIG. 11B is a block diagram for explaining the schematic configuration of the means, and FIG. 11B is a time sequence for explaining the operation. However, in FIG. 11B, the received signal data input from the Din input is the first to the first to compose the shift register.
4 shows the operation from the timing when the latch reaches the final stage.

In FIG. 11, 1101 is a first multiplier, 1102 is a second multiplier, 1103 is a third multiplier, 1104 is an adder, 1105 is a first latch,
06 is the second latch, 1107 is the third latch, 110
Reference numeral 8 denotes a fourth latch. In the interpolation processing means 801 of the present embodiment, the Din input is connected to one input of the first multiplier 1101 and the first multiplier 1101
The other input of the first multiplier 11 is connected to the output of the first filter coefficient Ai of the interpolation control means (not shown).
The output of 01 is connected to the input of adding means 1104.
Also, the Din input is the first input that constitutes a four-stage shift register.
, And the output of the first latch 1105 is connected to the input of a second latch 1106. The output of the second latch 1106 is connected to one input of a second multiplier 1102 and
Is connected to the input of the latch 1107. The output of the third latch 1107 is connected to the input of the fourth latch 1108. The output of the fourth latch 1108 is connected to the third multiplier 11
03 and the third multiplier 110
The other input of 3 is connected to the output of the filter coefficient Ci of the interpolation control means (not shown), and its output is connected to the input of the adder 1104. The other input of the second multiplier 1102 is connected to the output of the filter coefficient Bi of the interpolation control means (not shown), and the output is connected to the input of the adder 1104. The output of the adder 1104 is connected to the adding means 102 as a Dout output. However, the shift clock of the first to fourth latches 1105 to 1108 forming the shift register is the sampling clock Sck.

Next, based on FIG. 11B, FIG.
The operation of the interpolation processing means of this embodiment shown in FIG.

When the first sampling clock Sck shown in FIG. 11 is input, as shown by D1 to D5 in FIG. 11, one input of each of the multipliers 1101 to 1103 sequentially receives the Din input. Received signal data D input from
5. The received signal data D3 latched by the second latch 1106 and the received signal data D1 latched by the fourth latch 1108 are input. On the other hand, each of the multipliers 1101-1
To the other input of 103, filter coefficients A1, B1, and C1 corresponding to the reception phasing frequency f0 of the odd-number reception signal data are input from interpolation control means (not shown). Therefore, from the Dout output, the first sampling clock in FIG. 11B, that is, the odd-numbered tree is based on the signal data, and D1 * C1 (f0) + D3 * B1 (f
0) + D5 * A1 (f0) is output.

Next, the second sampling clock S
When ck is input, the received signal data D6 is input from the Din input, and the first to fourth latches 1105 to 110
8 is sequentially shifted by one stage, so that one input of each of the multipliers 1101 to 1103 has the received signal data D6 sequentially input from the Din input and the second input. Received signal data D4 latched by the latch 1106 and received signal data D2 latched by the fourth latch 1108 are input. At this time, each multiplier 110
The other input of 1 to 1103 is supplied from the interpolation control means (not shown) with the reception phasing frequency f0 of the odd-number reception signal data.
Are respectively input to the filter coefficients A2, B2, and C2. Therefore, from the Dout output, FIG.
D2 * C2 (f2) + D4 * B2 based on the second sampling clock, i.e., even-numbered received signal data.
(F2) + D6 * A2 (f2) is output.

Thereafter, by sequentially performing this operation,
Interpolation processing based on the odd-numbered received signal data and the even-numbered received signal data can be performed in time series.

In the present embodiment, the case where the interpolation filter is used in time series has been described. However, the present invention is not limited to this. For example, Japanese Patent Application Laid-Open No. HEI 3-123879.
It is needless to say that, as described in Japanese Patent Application Laid-Open Publication No. H10-209, an interpolation filter may be provided in parallel and each filter may perform an interpolation process at a dedicated frequency.

As described above, the ultrasonic apparatus according to the fourth embodiment satisfies the sampling theorem of the highest frequency to be handled, and when the effective sampling frequency decreases with time-series processing, AD of sampling frequency fs such that the frequency satisfies the sampling theorem
The received signal data converted by C100 is
1 performs reception phasing processing (delay processing) sequentially in time series in synchronization with the sampling cycle, thereby simultaneously forming a reception beam having a frequency f0 of the transmission signal and a frequency 2f0 which is twice as high as that of the transmission signal. Therefore, it is possible to display a harmonics video image without a time difference.

Therefore, the examiner such as a doctor can easily compare and examine the ultrasonic images of different reflection frequencies, so that the diagnosis efficiency can be improved.

In addition, an examiner such as a doctor can easily compare and examine ultrasonic images having different reflection frequencies.
Diagnosis accuracy can be improved.

(Embodiment 5) FIG. 12 is a diagram for explaining a schematic configuration of a wave phasing section in an ultrasonic apparatus according to Embodiment 5 of the present invention.
Indicates a wave transmission phasing circuit, and 1203 indicates a drive circuit.

In FIG. 12, adding means 1201 is a well-known adding means for adding the transmission waveforms 1 and 2 of different transmission frequencies inputted from the transmission signal generating means (not shown). Transmitting the transmission waveform signal to the phasing circuit 120
Output to 2.

The wave phasing circuit 1202 is a well-known wave phasing circuit that delays a transmitted signal supplied to each element of the probe 110 based on preset focal position information. A transmission signal corresponding to the element is output to the drive circuit 1203.

The drive circuit 1203 is a well-known drive circuit that buffers the input transmission signal, and supplies the buffered transmission signal to each element of the probe 110 via the element selection unit 111. Drive.

Next, the fifth embodiment will be described with reference to FIG.
The operation of the wave phasing unit 112 in the ultrasonic apparatus described above will be described. For example, the transmission waveforms 1 and 2 of a plurality of frequencies (here, two different frequencies) specified by the examiner are added by the adding means 1201. Thus, one transmission signal is synthesized. The combined transmission signal is transmitted to a transmission phasing circuit 1202.
After being converted into a transmission signal corresponding to each element in, the signal is buffered in the drive circuit 1203 and supplied to each element of the probe 110. Each element generates an ultrasonic wave corresponding to the drive signal, transmits the ultrasonic wave to an object (not shown), and the ultrasonic wave reflected in the object is detected by each element as a received signal. The received signal at this time is a received signal in which the received signal 1 corresponding to the frequency of the transmitted waveform 1 and the received signal 2 corresponding to the frequency of the transmitted waveform 2 are combined.

In the present embodiment, by setting the frequency of the transmission waveform 1 to f0 and the frequency of the transmission waveform 2 to f2, the ultrasonic apparatus according to the first to fourth embodiments described above
Basic frequency 4f0 (received phasing frequency f0) and double frequency 8f
The reception phasing processing of 0 (the reception phasing frequency f2) can be performed.

In this embodiment, as shown in FIG. 13, transmission signals having different focus positions corresponding to transmission signals of different transmission frequencies are combined and transmitted, that is, different transmission signals are used. A transmission signal having a different focus position corresponding to the transmission signal of the transmission frequency is simultaneously transmitted. For example, a transmission signal of the gate focus 1301 (the focus position is the focus point 1303 at this time) is generated by the transmission waveform 1 described above, and the transmission waveform 2
By generating a transmission signal of the gate focus 1302 (the focus position at this time is the focus point 1304), signals of different focus positions can be transmitted at the same time, and each focus position Since the frequency of the received signal is different,
Ultrasonic images at different focus positions can be easily generated. However, at the time of reception phasing, the reception phasing frequency is changed in multiple stages in accordance with the transmission focus position (transmission frequency), that is, instead of being changed alternately in time series, for example, according to the depth, In region 1 from time 0 to t1, reception phasing corresponding to the frequency of the transmission waveform 2 is performed, and when it is deeper (region 2 from time t1 to t2), reception is performed corresponding to the frequency of the transmission waveform 1. By performing wave phasing, for example, by changing the phasing frequency at a time that has elapsed from one transmission of the reception phasing frequency, it is possible to simultaneously realize the multi-stage focus of the transmission and the dynamic focus of the reception.

Therefore, the examiner can observe the ultrasonic images at different depths at the same time, so that the diagnosis efficiency can be improved.

[0109] Further, since multi-step focusing of the transmission becomes possible, a high-definition ultrasonic image can be displayed without lowering the frame rate.

In the above-described ultrasonic apparatuses according to the first to third embodiments, a method has been described in which the transmission is performed at the fundamental frequency and the reception is processed at the two frequencies of the fundamental frequency and the double frequency. It is needless to say that the transmission may be performed at two frequencies or a plurality of frequencies, transmitted for the number of times, received at each frequency, and displayed.

Further, the present invention can also be applied to the case where the transmission frequency is superimposed as a plurality of frequencies so as to have the same focus, and the reception processing is performed in parallel.

In the ultrasonic diagnostic apparatuses according to the first to third embodiments, the display modes are superimposed or alternate, but it goes without saying that the display mode selected by the examiner can be displayed. For example, a touch panel or a console is provided with a selection switch for selecting the double-frequency processing, in which simultaneous processing, alternate processing (basic wave processing and double-frequency processing are performed for each transmission) as processing methods (or functions). Mode), only the double frequency processing (reception phasing only performs the double frequency processing), and only the fundamental wave processing. As the display method, the former two modes include a mode in which a fundamental wave processed image and a double frequency processed image are superimposed and displayed, a mode in which they are displayed alternately, and a mode in which they are displayed in separate areas. In the mode of only the double frequency processing, only the double frequency processed image is displayed. In the case of superimposing, by adjusting the ratio and the superimposition ratio in the depth direction, a good image can be obtained at all depths.

Furthermore, in the ultrasonic apparatuses according to the first to fourth embodiments, the data obtained by performing the phasing processing at the frequency (center frequency) of the transmission signal and the frequency twice the frequency of the transmission signal are used. Since the data obtained by the phasing process can be displayed in a superimposed or alternate manner, the blood flow imaging can be improved.
For example, when a contrast agent is used, body motion is processed at a fundamental frequency, and blood flow is processed at a double frequency, thereby removing the body motion. Alternatively, since a portion desired to have high resolution can be processed at double frequency, there is an effect that the resolution of an ultrasonic image can be improved.

As described above, the invention made by the present inventor is:
Although specifically described based on the embodiments of the present invention, the present invention is not limited to the embodiments of the present invention, and it is needless to say that various modifications can be made without departing from the gist of the present invention. .

[0115]

The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) Two-frequency processing can be performed in a phasing type ultrasonic apparatus that performs processing in relation to the center frequency.

(2) Since the examiner such as a doctor can easily compare and examine the ultrasonic images having different reflection frequencies,
Diagnosis efficiency can be improved.

(3) An examiner such as a doctor can easily compare and examine ultrasonic images of different reflection frequencies.
Diagnosis accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining a schematic configuration of an ultrasonic apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining a schematic configuration of a wave receiving and phasing unit according to the first embodiment.

FIG. 3 is a diagram for explaining a schematic configuration of a delay unit, an addition unit, and a signal processing unit according to the first embodiment;

FIG. 4 is a time sequence of the ultrasonic apparatus according to the first embodiment.

FIG. 5 is a diagram for explaining a schematic configuration of an ultrasonic apparatus according to a second embodiment of the present invention.

FIG. 6 is a diagram for explaining a schematic configuration of an ultrasonic apparatus according to a third embodiment of the present invention.

FIG. 7 is a view for explaining a schematic configuration of an ultrasonic apparatus according to another embodiment of the present invention.

FIG. 8 is a diagram illustrating a schematic configuration of a delay unit, an addition unit, and a signal processing unit in the ultrasonic apparatus according to the fourth embodiment.

FIG. 9 is a diagram for explaining a time sequence of an interpolation process in a delay unit according to the fourth embodiment.

FIG. 10 is a diagram for explaining a configuration of a delay unit for implementing the interpolation processing (1) shown in FIG. 9;

11 is a diagram for explaining another configuration of the delay means for implementing the interpolation processing (1) shown in FIG.

FIG. 12 is a diagram illustrating a schematic configuration of a wave phasing unit in an ultrasonic apparatus according to a fifth embodiment of the present invention.

FIG. 13 is a diagram for explaining an operation of the ultrasonic apparatus according to the fifth embodiment of the present invention.

FIG. 14 is a diagram for explaining a transmitting and receiving operation of a conventional ultrasonic device.

FIG. 15 is a view for explaining a basic sampling method in a conventional ultrasonic apparatus.

[Explanation of symbols]

100 ADC, 101 delay means, 102 addition means, 103 sampling signal generation means, 103 a selection unit, 104 delay control means, 105 signal processing means,
105a ... 4f0 signal processing means, 105b ... 8f0 signal processing means, 106 ... display means, 107 ... memory, 108 ...
4f0 interpolation processing means, 109 ... 8f0 interpolation processing means, 11
0: probe, 111: element selection unit, 112: transmission phasing unit, 113: reception phasing unit, 701: complex signal conversion unit,
702: interpolation processing means, 801: interpolation processing means, 802
Is f0 signal processing means, 803 is f2 signal processing means, 100
1 is a frequency moving means, 1002 is a filter, 1101 to
1103 denotes first to third multipliers, 1104 denotes an adder, 11
05 to 1108 are first to fourth latches, 1201 is an adding means, 1202 is a wave phasing circuit, and 1203 is a drive circuit.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Jun Kubota 1-1-1 Uchikanda, Chiyoda-ku, Tokyo Inside Hitachi Medical Corporation (72) Inventor Satoshi Tamano 1-11-1 Uchikanda, Chiyoda-ku, Tokyo No. Hitachi Medical Corporation (72) Inventor Katsunori Asaba 1-1-1 Uchikanda, Chiyoda-ku, Tokyo Inside Hitachi Medical Corporation

Claims (18)

[Claims] 1. An ultrasonic transmission / reception means comprising a plurality of ultrasonic transducers for transmitting / receiving ultrasonic waves, a wave phasing means for delaying a reception signal, and a reception signal after the delay processing are added. An ultrasonic unit comprising: an adding unit that performs a transmission signal, and a display unit that sequentially displays a reception beam formed by the reception phasing unit and the addition unit as an ultrasonic image. Sampling means for sampling the received signal at a frequency eight times the frequency of the signal; and eight times delay processing means for delaying the received signal sampled by the sampling means at eight times the frequency interval of the transmitted signal; Quadruple delay processing means for delaying the reception signal sampled by the sampling means at a frequency interval four times the frequency of the transmission signal, wherein the transmission and reception of one ultrasonic wave phase The stage and the adding means form a reception beam of the frequency of the transmission signal from the reception signal after the 4-fold delay processing, and form a reception beam of a double frequency from the reception signal after the 8-fold delay processing. Ultrasonic device. 2. The ultrasonic apparatus according to claim 1, wherein said ultrasonic transmitting and receiving means matches a center frequency of said ultrasonic transducer with a frequency of said transmission signal. apparatus. 3. The ultrasonic apparatus according to claim 1, wherein the sampling unit performs sampling in accordance with a wavefront of the received signal from a focus point, and performs a delay shorter than a sampling interval. An ultrasonic device, comprising: 4. The ultrasonic apparatus according to claim 1, wherein said sampling means is a means for performing sampling in the same phase, and said reception phasing means is an interpolation means for performing a delay shorter than said sampling interval. An ultrasonic device, comprising: 5. The ultrasonic device according to claim 1, wherein the ultrasonic transmitting / receiving unit transmits an ultrasonic wave at a center frequency of the ultrasonic vibrator and receives the ultrasonic wave. The phasing means and the adding means may include a center frequency of the ultrasonic vibrator and two of the center frequency.
An ultrasonic apparatus, wherein a reception beam is sequentially formed from a reception signal at a double frequency. 5. The ultrasonic device according to claim 1, wherein the display unit includes an ultrasonic beam formed from the center frequency and a frequency twice as high as the center frequency. An ultrasonic apparatus characterized by displaying an overlapped ultrasonic beam. 6. The ultrasonic device according to claim 1, wherein the display unit includes an ultrasonic beam formed from the center frequency and a frequency twice the center frequency. An ultrasonic apparatus characterized by alternately displaying the generated ultrasonic beams. 7. An ultrasonic transmission / reception means comprising a plurality of ultrasonic transducers for transmitting / receiving ultrasonic waves, a wave phasing means for delaying a reception signal, and a reception signal after the delay processing are added. An ultrasonic device comprising: an adding unit that performs the above operation; and a display unit that sequentially displays, as an ultrasonic image, the reception beam formed by the reception phasing unit and the addition unit. An ultrasonic apparatus comprising: a beam forming means for forming an ultrasonic beam formed from a frequency of a transmission signal from a reception signal obtained by transmission and an ultrasonic beam formed from a double frequency. . 8. The ultrasonic apparatus according to claim 7, wherein the beam forming means forms an ultrasonic beam sequentially in a time division manner from a frequency of the transmission signal and a frequency twice as high as the transmission signal. An ultrasonic device, which is a means. 9. The ultrasonic apparatus according to claim 7, wherein said time-division forming means includes frequency moving means for moving a frequency of a received signal by mixing. 10. The ultrasonic apparatus according to claim 9, wherein said frequency shifting means has a mixing signal corresponding to a frequency of a transmission signal and a frequency twice as high as that of the transmission signal. An ultrasonic apparatus characterized in that two mixing frequencies are used alternately, and an ultrasonic beam is formed in a time-division manner from a frequency of a transmission signal and a frequency twice as high as the transmission signal. 11. The ultrasonic apparatus according to claim 7, wherein the reception phasing means has an interpolation coefficient corresponding to a frequency of the transmission signal and a frequency twice as high as that of the transmission signal. An ultrasonic apparatus, wherein the reception phasing means alternately uses the interpolation coefficients to form an ultrasonic beam in a time division manner from a frequency of a transmission signal and a frequency twice as high as the transmission signal. . 12. The ultrasonic apparatus according to claim 7, wherein the display unit includes an ultrasonic beam formed from a frequency of the transmission signal and a frequency twice as high as the transmission signal. An ultrasonic apparatus characterized by superimposing and displaying an ultrasonic beam formed from a superposition based on a preset superimposition ratio. 13. An ultrasonic transmission / reception means comprising a plurality of ultrasonic transducers for transmitting / receiving ultrasonic waves, a wave phasing means for delaying a reception signal, and a reception signal after the delay processing are added. An ultrasonic unit comprising: an adding unit that performs the ultrasonic vibration; and a display unit that sequentially displays, as an ultrasonic image, the received beam formed by the receiving phasing unit and the adding unit. A transmission means for transmitting a first transmission signal having a center frequency of the child and a second transmission signal having a frequency different from that of the first transmission signal in one transmission in the same direction; An ultrasonic device, characterized in that: 14. An ultrasonic transmission / reception means comprising a plurality of ultrasonic transducers for transmitting / receiving ultrasonic waves, a wave phasing means for delaying a reception signal, and a reception signal after the delay processing are added. An ultrasonic unit comprising: an adding unit for performing the above operation; and a display unit for sequentially displaying, as an ultrasonic image, the reception beam formed by the reception phasing unit and the addition unit. Means for transmitting a first transmission signal having a center frequency of the first transmission signal and a second transmission signal having a frequency different from that of the first transmission signal in one transmission in the same direction; The wave phasing means includes an ultrasonic beam formed from the frequency of the first transmission signal and an ultrasonic beam formed from the frequency of the second transmission signal from the reception signal obtained by one transmission. An ultrasonic apparatus comprising a beam forming means for forming a beam. 15. The ultrasonic apparatus according to claim 13, wherein the reception phasing unit performs sampling processing of sampling the reception signal in the same phase and delay processing shorter than the sampling interval. An ultrasonic apparatus comprising: an interpolation unit that performs an interpolation operation to be performed. 16. The ultrasonic apparatus according to claim 13, wherein said transmitting means sets different focus positions for said first transmitting signal and said second transmitting signal, respectively. Ultrasound device. 17. The ultrasonic apparatus according to claim 16, wherein said transmitting means allocates a high-frequency transmitting signal to a near focus position. 18. The ultrasonic apparatus according to claim 17, wherein said beam forming means performs reception phasing of a reception signal based on a frequency assigned to a focus area. .