JPH0556906B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a reflected wave receiving hearing observation device, particularly an ultrasonic diagnostic device that transmits and receives ultrasound waves to and from a subject to obtain a diagnostic image of an affected area, or a device that moves electromagnetic waves. The present invention relates to a reflection reception listening observation device that observes a subject or a moving object using a radar observation device that measures the position, velocity, etc. of an object by transmitting and receiving waves to and from the object.

[Prior art] In the medical field, ultrasonic waves are transmitted and received to a subject, and the reflected waves from the subject are displayed as an image.
Ultrasonic diagnostic devices for observing affected areas are widely used.

That is, this type of ultrasonic diagnostic apparatus converts the received reflected wave into a digital signal, then scans the digital signal at a speed necessary for image display, and displays the signal on a television monitor as a diagnostic image.

Therefore, the diagnostician visually observes the affected area of the subject by looking at the diagnostic image, and makes an appropriate diagnosis for the patient.

In addition to this, stethoscopes are widely used as a device for making diagnoses by listening to sounds, as is well known. Diagnosis using a stethoscope is performed by a diagnostician listening to sounds generated within the subject, such as the heartbeat.

In such a diagnosis using a stethoscope, hearing has a special ability to selectively distinguish sounds, unlike vision.

Therefore, a diagnostician using a stethoscope was able to distinguish subtle changes and differences in sound by hearing, and this enabled him to make an appropriate judgment of the situation and make a diagnosis.

On the other hand, in the communications field, radar observation equipment is
It can detect targets using electromagnetic waves, and its purpose is to acquire, process, and display information about objects. In other words, this device transmits and receives electromagnetic waves to receive the reflected waves that hit the target and determine the distance and direction of the target (such as a moving object) from the round trip time or the Doppler effect. It measures speed and is widely used for weather observation, monitoring of ships and aircraft, and navigation.

This type of radar observation device is mainly used for
Observations were made by displaying images on a CRT display. That is, when navigating a ship, for example, a pilot monitors the route and current position by radar observation as necessary, and operates while visually confirming the route and current position. Some models have a guard range that indicates the distance or angle range, and an alarm is generated when a target comes within that range. There were no examples of this being reproduced in sound.

[Problems to be Solved by the Invention] However, according to the above-mentioned conventional ultrasonic diagnostic equipment or radar observation equipment, reflected waves of sound waves and electromagnetic waves are displayed as observation images, which allows the observer to perform visual confirmation, i.e. Diagnosis or observation was performed only by sight.

Therefore, in this type of device, observation has not been performed using the sense of hearing, which has the ability to selectively distinguish sounds. For example, the auditory sense can instantly distinguish between two musical tones with a semitone difference in 0.1 seconds, but in order to visually distinguish this, Fourier analysis is used as a digital signal processing method to display an image. you need to do,
In current FFT analysis, even if Fourier analysis is performed,
It was impossible.

In other words, even if it is impossible to display images of reflected waves from an object and visually analyze subtle changes, the above-mentioned audible sound can be achieved by making the reflected waves emit from the same object and listening to them. There were cases where it was possible to analyze and observe subtle changes in abilities.

In addition, with regard to hearing, which is a highly analytical ability possessed by humans, conventional stethoscopes were used to diagnose the body by listening to the sounds generated by the subject, as mentioned above, but the diagnosis was made by listening to the sounds generated by the subject. Diagnosis was impossible.

On the other hand, in radar observation devices, all observations have conventionally been performed by displaying images, and there has been no practice of emitting sounds for the observer to listen to.

Purpose of the Invention The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to convert subtle changes in reflected waves from an observation area into sound in ultrasonic diagnostic equipment and radar observation equipment. The object of the present invention is to provide a reflected wave receiving listening observation device that enables listening and observing and analyzing objects.

[Means for Solving the Problems] In order to achieve the above object, according to the reflected wave receiving listening observation device of the present invention, a sound wave or an electromagnetic wave is transmitted to an observation object, and the reflected wave is reflected by a specific area of the object. a transducer for receiving the reflected wave; a storage means for sampling and storing the reflected wave received by the transducer; and repeating the reflected wave stored by the storage means at a predetermined reproduction repetition frequency at a low speed. A low-speed readout means for reading and converting the sound wave into a time-expanded predetermined sound wave in the audible frequency range; and a component and sample below the reproduction repetition frequency by performing bandpass filtering on the predetermined sound wave in the audible frequency range obtained by the low-speed readout means. and bandpass filtering means for removing components higher than the frequency at which the sound waves are converted into an audio frequency range by the low-speed readout means and bandpass filtered by the bandpass filtering means.

Further, the present invention is characterized in that the time magnification rate is in the range of several hundred times to several thousand times.

[Operation] With the above configuration, according to the present invention, when a reflected wave of a sound wave or an electromagnetic wave is received from a specific region of an object through wave transmission and reception, the reflected wave is stored in the storage means.

Then, the stored reflected wave is read out at low speed by the low-speed reading means, thereby generating a predetermined sound wave in the audio frequency range converted according to the reflected wave.

Therefore, when an observer hears this pronunciation,
Subtle changes in the reflected waves of sound waves or electromagnetic waves can be heard, allowing the observer to analyze changes and properties of objects in a particular observation area.

Further, in the present invention, the predetermined sound wave in the audible frequency range obtained by the low-speed reading means is band-filtered by the band-pass filtering means. The components that are removed at this time are components that are lower than the reproduction repetition frequency and components that are higher than the frequency obtained by dividing the sampling frequency by the time expansion rate. Therefore, in the present invention, it is possible to prevent the reproduction repetition frequency from having an adverse effect on the auditory sense, or the component obtained by expanding the sampling frequency in time from having an adverse effect on the auditory sense, thereby providing a highly usable device.

[Embodiment] Fig. 1 shows a preferred first embodiment of the reflected wave reception hearing observation device according to the present invention, and this Fig. 1 shows the case where it is used in an ultrasonic diagnostic device. It is a block diagram.

The characteristic feature of the present invention is that by storing the reflected waves received from the observed object and reading them out at low speed, a predetermined sound wave in the audio frequency range that is converted according to changes in the reflected waves is generated. be.

Next, the configuration of the first embodiment according to the present invention will be described below.

In FIG. 1, a subject 5 represents an organ, such as a heart or a blood vessel. The probe 10 as a transducer is an ultrasonic probe for transmitting and receiving ultrasonic waves, and the logarithmic characteristic amplification detector 12 logarithmically transforms the reflected wave input and amplifies it to a predetermined level. This is an amplifier that outputs A/D
The converter 14 is a converter that converts an analog input signal to a digital output signal, and the storage circuit 16 is a converter that converts an analog input signal to a digital output signal.
It is a memory, such as a RAM, that stores the digital output signal.

The low-speed readout circuit 18 is a circuit for reading out the stored digital output signal at a predetermined low speed. For example, during reading, the digital signal is read out at a slower speed than the writing speed at the time of storage. A predetermined sound wave in the audio frequency range is obtained according to the reflected wave. Furthermore, the stored signal is repeatedly played back in order to extend the listening time for several seconds.

Further, the bandpass filter 20 is a filter for cutting harmonic components corresponding to the sampling frequency and the Nyquist number wave number or higher when the low-speed reading is performed, and low frequency components corresponding to the repetition period or lower, The audio amplifier 22 amplifies frequencies in the audio frequency range to a predetermined level.

The speaker 24 is a headphone for producing sound so that the observer can hear the sound faithfully.

Next, its operation will be explained.

As shown in FIG. 1, when ultrasonic waves are transmitted from the probe 10 to the subject 5, the reflected waves reflected by a specific area of the affected area of the subject are received by the probe 10.

Therefore, the reflected wave that hits the affected area and is received is input to the logarithmic characteristic amplification detector 12,
After being mixed and amplified at a predetermined level, the A/D converter 1
4, the signal is converted into a digital signal in real time at a sampling frequency of several MHz, for example. When performing normal sampling, the reflected wave frequency, which is more than half of the sampling frequency, is removed before the A/D converter 14.
Alternatively, the reflected sound is processed with a filter that removes frequencies higher than the highest frequency of the necessary reflected sound, but this is omitted for the sake of explanation as it is a matter of course.

As a result, the reflected wave is changed into a digital signal, and the storage circuit 16 converts the reflected wave into a digital signal 16a.
to be memorized. Here, the reflected wave digital signal 1
6a is written into the storage circuit 16 at the same speed as the speed at which the reflected wave is received, but when reading the reflected wave digital signal 16a from the storage circuit 16, it is written at a slower rate than that speed. The data is read out at a predetermined low speed. That is, in the low-speed readout circuit 18, reading is performed at a slow speed of, for example, about 1/1000 of the time of storage, that is, a speed that is expanded by about 1000 times, and the readout is performed at several KHz compared to several MHz during writing.

Therefore, the reflected wave digital signal 16a can be converted into an audio frequency range, for example, an audio frequency band of several tens of Hz to several KHz.

Of course, the low-speed readout reflected wave signal 18a outputted by the low-speed readout circuit 18 is converted into an analog output signal, and the bandpass filter 20 inputs the low-speed readout reflected wave signal 18a and calculates the signal related to the sampling frequency. Only the signal components in the reflected wave region from which the harmonic components (components higher than the sampling frequency/time expansion rate) and the low frequencies of the repetition frequency during repeated playback are removed are obtained and output as the audio frequency signal 20a. .

The audio frequency signal 20a is transmitted to an audio amplifier 22.
The low frequency is amplified by the speaker 24 of the headphone etc.
You can make the sound sound by

As a result, the reflected waves reflected by the affected area of the subject are faithfully converted into predetermined sound waves in the audio frequency range,
This allows the observer to hear audible sounds corresponding to the reflected waves at an appropriate volume.

According to the low-speed readout circuit 18 of this embodiment, since the readout time is extended due to low-speed readout, the audible sound becomes a signal at the time of reception for one of the transmitted pulses. When adding circuitry, the signal is thinned out during some pulse repetition periods during reception.

Next, FIG. 2 shows a second embodiment of the present invention, and this FIG. 2 is a block diagram showing the case where it is applied to a radar observation device.

Next, the second embodiment shown in FIG. 2 will be explained. The same members as in the first embodiment shown in FIG. , the explanation will be omitted below. In the second embodiment, the transmission system not related to the present invention is omitted.

As shown in FIG. 2, the differences from the first embodiment (FIG. 1) are in the moving body 5 as an observation object and the antenna 11 as a transducer since it relates to a radar observation device. , the subject 5 and the probe 10 in FIG. 1 in the ultrasonic diagnostic apparatus described above.
There is a difference between

That is, in FIG. 2, the moving object 6 is, for example, a moving observation object, such as a ship. Of course, it can also be applied to surrounding sea phenomena such as typhoons, storms, waves, etc.

Further, the antenna 11 is a transducer for transmitting and receiving electromagnetic waves, as is well known.

From the above, in the case of a radar observation device, the reflected wave reception signal from the antenna 11 generates an image signal in the logarithmic characteristic reception circuit 32.

Here, since the bandwidth and repetition period (frequency) of this image signal are usually almost the same as those of an ultrasonic diagnostic device, the explanation of the operation after the A/D converter shown in Fig. 2 is as described above. Since it is the same as the first embodiment shown in FIG. 1, the explanation will be omitted.

[Effects of the Invention] As described above, according to the reflected wave receiving listening observation device according to the present invention, instead of visually confirming and observing the reflected waves reflected from the observation object as in the past, the reflected waves are By faithfully converting the reflected wave into a predetermined sound wave in the audio frequency range, it is possible to generate a predetermined sound wave corresponding to the reflected wave. Therefore, the observer can detect subtle changes in the reflected sound by listening.

For this reason, there is an effect that the properties and changes of an object, which could not be observed visually using conventional image display, can be known by making sounds and listening to the sounds.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of a reflected wave reception listening observation device according to the present invention, and FIG.
FIG. 2 is a block diagram showing a second embodiment of a reflected wave reception listening observation device according to the present invention. 5... Subject, 6... Moving object, 10... Probe, 11... Antenna, 16... Memory circuit, 16
a...Reflected wave digital signal, 18...Low speed readout circuit, 22...Audio amplifier, 24...Speaker.

Claims (1)

[Scope of Claims] 1. A transducer that transmits sound waves or electromagnetic waves to an observation object and receives the reflected waves reflected by a specific area of the object, and a transducer that transmits the reflected waves received by the transducer. a storage means for sampling and storing the sample; and repeatedly reading the reflected waves stored by the storage means at a low speed at a predetermined reproduction repetition frequency;
a low-speed readout means for converting into a time-expanded predetermined sound wave in the audible frequency range; and bandpass filtering of the predetermined sound wave in the audible frequency range obtained by the low-speed readout means to obtain components below the reproduction repetition frequency and above the sampling frequency. a bandpass filtering means for removing a component; and a reflected wave reception listening device characterized in that it emits a sound wave that has been converted into an audio frequency range by the low-speed reading means and further bandpassfiltered by the bandpass filtering means. Observation equipment. 2. The reflected wave receiving hearing and observing device according to claim 1, wherein the time magnification is in the range of several hundred times to several thousand times.