JPS6130211Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic device, particularly to a device that simultaneously obtains reflected waves and transmitted waves.

In recent years, it has become possible to generate sound waves of up to 1 GHz, making it possible to realize a sound wavelength of approximately 1 μm underwater, and thus creating the possibility of obtaining a high-resolution sound wave imaging device. A natural extension of the technology established in the MHz range is the use of concave lenses to create focused acoustic beams.
Attempts have been made to realize resolutions as high as 1 μ. In other words, a sample is placed into this beam, and the reflected and transmitted sound waves from the sample are detected to obtain information reflecting the elastic properties of the sample, or the sample is mechanically scanned to create an image. .

In such a configuration, it is desirable to be able to simultaneously detect and image reflected signals and transmitted signals. The purpose of this invention is to simultaneously detect reflected signals and transmitted signals with a simple configuration.The gist of this invention is to use a pulsed RF signal, and essentially use a delay device as a means to temporally separate the reflected signals and transmitted signals. The point is to use An embodiment will be described below with reference to the drawings. By applying an RF electric signal from the RF oscillator 10 to the piezoelectric body 16 formed on the end face of the sonic lens 18, water is generated.
An extremely narrow ultrasonic beam is irradiated onto the sample 22 supported in the center 20, and its reflected signal is detected by a lens 18, or its transmitted signal is detected by a detector consisting of a lens 26 and a piezoelectric body 28. In this way, a reflected signal separated from the applied signal by the directional coupler 14 and a transmitted signal amplified by the RF amplifier 30 are obtained, and this configuration is the same for RF continuous waves. However, in this case, the separation of the applied signal and the reflected signal is dependent on the directionality of the coupler 14 and is not sufficient, and two points are required to convert the signal into a video signal.
An RF detector is required. In this invention, pulsar
12 pulse-modulates the oscillator 10 and applies an RF burst wave. In Figure 2, I and I' are this RF
This is a burst wave, and by applying this to the piezoelectric body 16, a reflected RF signal R and a transmitted RF signal T are obtained. The fact that R and T can be distinguished in time is due to the addition of the RF variable delay device 32 in this embodiment. In such a configuration, T
and R whose amplitude is limited by the limiter 34 are temporally differentiated, so even if they are added by the combiner 36, they will not be confused. The added RF signal is 3 in Figure 2.
As shown in Figure 2 (4) by the RF detector 38,
You can get a video signal like pulsar 12
The gate signal controlled by the gate signal makes it possible to obtain the reflected signal R'' and the transmitted signal T'' separately and simultaneously in the video domain using the beak detectors 40 and 42.

In such a configuration, since an RF burst signal is used, it is extremely easy to distinguish between the RF applied signal and the RF reflected signal, and since a delay device is used, the RF reflected signal and the RF transmitted signal are not confused in the RF domain. It is possible to add them, and it takes one digit to detect them.
It has the advantages of being able to separate reflected signals and transmitted signals using only an RF detector in the video area, which is easy to handle, and also being able to separate complex multiple reflected signals.
In sonic devices in the RF signal region, such as sonic microscopes and sonic spectroscopy, it becomes extremely easy to separate and simultaneously detect transmitted and reflected sound waves, and the configuration of these devices can be significantly simplified.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is an explanatory diagram of its operation.

Claims (1)

[Scope of utility model registration request] means for detecting reflected waves and transmitted waves of ultrasonic waves from the sample generated by irradiating the sample with ultrasonic pulses; means for giving a predetermined delay to the transmitted waves; and means for detecting the reflected waves and the delayed transmitted waves. An ultrasonic device comprising a means for mixing and capable of extracting both signals using a common detector.