JPH0812243B2 - Ultrasonic scanning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention has an ultrasonic diagnostic apparatus, and in particular, has a plurality of ultrasonic transducers arranged in an array, and a vibrating surface of the transducers is applied to a subject. Of an ultrasonic scanning device that electronically scans a plurality of transducers so that the transmitted and received ultrasonic beams are directed, and the transmission / reception state is a plurality of continuous scans that move substantially parallel to the transducer surface. Regarding improvement.

[Prior Art] In recent years, ultrasonic diagnostic apparatuses that perform diagnostics using ultrasonic waves are widely used. This ultrasonic diagnostic apparatus utilizes that tissues and organs in the body have different acoustic characteristics. That is, it is utilized that when an ultrasonic wave is incident on the body for a very short time, a part of the ultrasonic wave is reflected back from the boundary between different tissues while propagating in the human body.

More specifically, the ultrasonic pulse is repeatedly emitted at a constant cycle so that the ultrasonic beam is focused and emitted in one direction in order to narrow the ultrasonic beam, and the ultrasonic pulse is sequentially transmitted while propagating in the body. Detects the reflected echo that occurs,
By displaying the distribution of the acoustic characteristics of the internal tissues as an image, the state inside the body can be observed.

Therefore, if such an operation is performed over each part of the body, that is, the ultrasonic beam focused as described above scans the inside of the body at regular intervals, and the reflected echo is displayed on a display such as a cathode ray tube by the scanning. By doing so, a tomographic image (plane) of the distribution of acoustic characteristics in the body can be obtained.

By the way, as a typical ultrasonic transmission / reception system used for performing the above-mentioned ultrasonic diagnostic method, there is a system shown in FIG.

As shown in FIG. 4, a sufficiently small electroacoustic transducer,
That is, a plurality of ultrasonic transducers (hereinafter, abbreviated as transducers) T1 to Tn are arranged in a one-dimensional direction with respect to the transmission circuit XT, and transmission signals D1 to Dm are used to transmit the transmission control signal TCNT. Under control, these transducers T1 to Tn are divided into m blocks t each along the array direction, and these blocks t
Are simultaneously energized, and then the energization is sequentially repeated while sequentially shifting the transducers forming the block t one by one, thereby forming a total of M scanning lines 1.

Hereinafter, the array of transducers used in such a system is simply referred to as an array.

Each of the m transducers that are simultaneously energized by the transmission signals D1 to Dm has a delay time for narrowing the ultrasonic beam and focusing it in one direction. Is set by.

However, in the method as shown in FIG. 4, no scanning line is formed for the m-1 transducers at both ends of the transducer array. That is, a scan line over the entire length of the array cannot be obtained, and the total number of scan lines M is M = n- (m- 1) = n−m + 1.

In view of this, if the scanning line starts and ends at both ends of the array so as to obtain a scanning line over the entire length of the array, a transmission circuit to which a transducer is not connected is generated. That is, since a blank shot occurs, a problem arises in that when receiving the reflected echoes over various parts of the body tissue, these necessary reception signals are buried in the electrical vibration of the blank shot.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-described circumstances, and an object thereof is to freely set the number M of scanning lines to M ≧ n−m + 1. In addition, by providing the ultrasonic scanning device which appropriately scans and transmits and receives ultrasonic waves so that a wider range of ultrasonic diagnostic images can be obtained by preventing the above-mentioned blank hitting. is there.

[Means for Solving Problems] In order to achieve such an object, in the present invention, the correspondence relationship between the delay time and the simultaneously energized oscillators is maintained and the number of simultaneously energized oscillators is reduced. It is possible to stop the transmission trigger to the transmission circuit that supplies electric energy to the vibrator.

That is, the present invention provides a transducer array (ARY) composed of a plurality of n electroacoustic transducers arranged in an array,
Addresses are sequentially assigned to a location where a plurality of n electroacoustic conversion elements are arranged and a location where the electroacoustic conversion elements outside both ends of the array are not connected, and a plurality of m addresses that are adjacent to each other are sequentially arranged. An address setting circuit (LAD) that is set by shifting one by one in one direction and is generated as a scanning line control signal (LADS), and a delay time of m electro-acoustic transducers is set and m delay pulses are set. Delay time selection circuit (MUXDS) that generates a transmission signal (MUXDS)
D), a transmission control circuit (CNT, TL) that generates a transmission control signal (TLS, CNS) based on the scanning line control signal (LADS), and the transmission signal (MUXD
S) to generate electric pulses based on m transmission circuits, and the transmission circuits are connected to the transmission control signal (TLS,
A transmission matrix circuit (MUX1, MUX) connected to the electroacoustic conversion element based on CNS) and energizing the electroacoustic conversion element by an electric pulse generated from the transmission circuit.
2) and an ultrasonic scanning device that generates periodic continuous scanning lines that move substantially parallel to the transducer array (ARY), based on the scanning line control signal (LADS), A transmission stop signal generation circuit (HP) that generates a transmission stop signal (HPS) that stops transmission to the transmission circuit to which the electroacoustic conversion element is not connected, and the transmission based on the transmission stop signal (HPS). A transmission stop selection circuit (TSW) for transmitting a transmission signal (TSWS) in which a pulse for stopping transmission of m delayed pulses of the signal (MUXDS) is turned off to the m transmission circuits.

[Operation] According to the present invention, a transducer array composed of a plurality of n electroacoustic transducers arranged in an array, a location where a plurality of n electroacoustic transducers are arranged, and outside of both ends of the arrangement. Addresses are sequentially assigned to locations to which the electroacoustic transducer is not connected, and a plurality of adjacent m addresses are sequentially set one by one while being set in one direction to generate scan line control signals. A circuit, a delay time selection circuit that sets a delay time of the m electroacoustic conversion elements to generate a transmission signal composed of m delay pulses, and a scanning line control signal,
A transmission control circuit which generates a transmission control signal, and an electric pulse which is generated based on the transmission signal
A transmission matrix circuit having a plurality of transmission circuits, the transmission circuits being connected to the electroacoustic conversion element based on the transmission control signal, and energizing the electroacoustic conversion elements by electric pulses generated from the transmission circuit. m transmission circuits, the transmission circuit is connected to the electroacoustic conversion element based on the transmission control signal, and the electroacoustic conversion element is generated by an electric pulse generated from the transmission circuit based on the transmission signal. A transmission matrix circuit for energizing the ultrasonic transducer and generating a periodic continuous scanning line moving substantially parallel to the transducer array, based on the scanning line control signal. A transmission stop signal generation circuit for generating a transmission stop signal for stopping transmission to the transmission circuit to which an acoustic conversion element is not connected; A transmission stop selection circuit for transmitting to the m transmission circuits a transmission signal in which a pulse for stopping transmission of the m delayed pulses of the transmission signal is turned off based on the stop signal; The number of scanning lines is increased and a wider range of diagnostic images is obtained by preventing the transmission circuit that is not connected to the child from being idle and providing a control circuit for stopping transmission to the vibrator that you do not want to energize. be able to.

[Examples] Hereinafter, the present invention will be described in detail and specifically with reference to the drawings.

 One embodiment of the present invention is shown in FIG.

In FIG. 1, P in the drawing is a pulse generation circuit,
The operation of the entire circuit shown in the figure is started at the timing of the leading edge and the trailing edge of the pulse PS generated by the pulse generating circuit P.

The LAD is an address setting circuit that reads an address signal TAD transmitted from a control circuit of another system and sets addresses of m transducers that are simultaneously activated in the array.

DLY is a delay time generation circuit that generates a delay time signal DLYS for focusing ultrasonic waves.

The MUXD is a delay time selection circuit that selects, from the delay time signals DLYS generated by the delay time generation circuit DLY, the delay times of m transducers that are simultaneously activated under the control of the probe code signal PCD.

Of the m transducers that are energized at the same time, TSW sends the transmission signal to the transmission circuit to which the transducer is not connected and the transmission signal to the transmission circuit when there is a transducer that you do not want to energize. It is a transmission stop selection circuit for stopping transmission.

MUX1 and MUX2 are transmission matrix circuits in which switches are arranged in a matrix, and are circuits for selecting m transducers to be simultaneously activated from all n transducers in the transducer array ARY. is there.

HP is a transmission stop signal generation circuit that generates a transmission stop signal that controls the transmission stop generation circuit TSW.

TL and CNT are transmission matrix circuits MUX1 and MUX
It is a transmission control circuit that controls 2.

Reference numeral R is a receiving circuit for receiving and processing the signal received by the transducer of the array ARY via the transmission matrix circuit MUX2.

Next, the operation of the embodiment of the present invention shown in FIG. 1 will be described.

FIG. 2 shows an example of the operation timing of the embodiment of the present invention.

As shown in FIG. 2, the pulse PS generated by the pulse generation circuit P and the transmission address signal TAD are generated at the same timing. At the timing of the leading edge of the pulse PS, the transmission address signal TAD is decoded by the address setting circuit LAD having the ROM configuration, and the scanning line control signal LADS is output.

The scanning line control signal LADS is supplied to the transmission control circuits CNT and TL and the transmission stop signal generation circuit HP and latched until the next pulse PS comes. The transmission control signals CNT and TL and the transmission stop signal generation circuit HP output the transmission control signals CNS and TLS and the transmission stop signal HPS, respectively, while shifting the timing.

On the other hand, at the timing of the trailing edge of the pulse PS, the delay time generation circuit DLY forms the delay time signal DLYS, and the delay time selection circuit MUXD produces the probe code signal PCD.
Set the delay time of m transducers that are activated simultaneously.

The signal output from the delay time selection circuit MUXD, that is, the first
The transmission signal MUXDS is as m delay time pulse signals,
Input to the transmission stop selection circuit TSW. Here, the transmission stop signal HPS turns off only the portion of the m first transmission signals MUXDS at which transmission is desired to be stopped.

In the second transmission signal TSW, as shown in the example of the figure, the transmission-reduced points 1, 2, and 3 are turned off.

The second transmission signal TSWS selects m transducers to be simultaneously energized from all n transducers in the array by the transmission control signals CNS and TLS in the transmission matrix circuits MUX1 and MUX2, and the transmission matrix circuit MUX2 Transmitter circuit in the
That is, the ultrasonic waves are radiated toward the body through the portion of the circuit that is directly connected to the vibrator and that acoustically converts the electric pulse.

In this way, the scan line 1 extending over the entire length of the array as shown in FIG. 3 was obtained. Further, since the transmission signal is turned off only at the portion where the transmission is desired to be stopped by the transmission stop signal HPS, it is possible to prevent the blank driving.

EFFECTS OF THE INVENTION According to the present invention, a transducer array composed of a plurality of n electroacoustic transducers arranged in an array, a location where a plurality of n electroacoustic transducers are arranged, and both ends of the array. Addresses are sequentially assigned to the external parts to which the electro-acoustic conversion element is not connected, and a plurality of adjacent m addresses are sequentially set one by one in one direction to generate scanning line control signals. An address setting circuit, a delay time selection circuit that sets a delay time of the m electroacoustic transducers to generate a transmission signal composed of m delay pulses, and a scanning line control signal based on the scanning line control signal.
A transmission control circuit which generates a transmission control signal, and an electric pulse which is generated based on the transmission signal
A transmission matrix circuit having a plurality of transmission circuits, the transmission circuits being connected to the electroacoustic conversion element based on the transmission control signal, and energizing the electroacoustic conversion elements by electric pulses generated from the transmission circuit. m transmission circuits, the transmission circuit is connected to the electroacoustic conversion element based on the transmission control signal, and the electroacoustic conversion element is generated by an electric pulse generated from the transmission circuit based on the transmission signal. A transmission matrix circuit for energizing the ultrasonic transducer and generating a periodic continuous scanning line moving substantially parallel to the transducer array, based on the scanning line control signal. A transmission stop signal generation circuit for generating a transmission stop signal for stopping transmission to the transmission circuit to which an acoustic conversion element is not connected; A transmission stop selection circuit for transmitting to the m transmission circuits a transmission signal in which a pulse for stopping transmission of the m delayed pulses of the transmission signal is turned off based on the stop signal; The number of scanning lines is increased and a wider range of diagnostic images is obtained by preventing the transmission circuit that is not connected to the child from being idle and providing a control circuit for stopping transmission to the vibrator that you do not want to energize. be able to.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention, FIG. 2 is a timing chart showing operation timing in the embodiment of the present invention, FIG. 3 is an explanatory view of the embodiment of the present invention, and FIG. FIG. 6 is a block diagram showing an example of a conventional scanning method. XT ... Transmitting circuit, TCNT ... Transmitting control, D1 to Dm ... Transmitting signal, T1 to Tn ... Electroacoustic transducer (transducer), t ... Transmitting block, l ... Scanning line, R ... Receiving Circuit, ARY ... Array, DLYS ... Delay time signal.

Claims (1)

[Claims] 1. A transducer array composed of a plurality of n electroacoustic transducers arranged in an array, a location where a plurality of n electroacoustic transducers are arranged, and the electroacoustic transducers outside the both ends of the array. An address setting circuit that sequentially assigns addresses to locations to which elements are not connected, sets a plurality of adjacent m addresses one by one in sequence in one direction, and generates a scanning line control signal, and m A delay time selection circuit for setting a delay time of each of the electroacoustic conversion elements to generate a transmission signal composed of m delay pulses; and a transmission control circuit for generating a transmission control signal based on the scanning line control signal. And m transmission circuits that generate electric pulses based on the transmission signal, and the transmission circuits include the transmission circuits based on the transmission control signal. A transmission matrix circuit connected to the electroacoustic conversion element and activating the electroacoustic conversion element by an electric pulse generated from the transmission circuit, and a periodic continuous scan moving substantially parallel to the transducer array. In an ultrasonic scanning device that generates a line, a transmission stop signal generation circuit that generates a transmission stop signal that stops transmission to the transmission circuit to which the electroacoustic conversion element is not connected, based on the scanning line control signal, A transmission stop selection circuit for transmitting, to the m transmission circuits, a transmission signal in which a pulse for stopping transmission among the m delayed pulses of the transmission signal is turned off based on the transmission stop signal. An ultrasonic scanning device characterized by the above.