JPS6210449B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic logic element that converts electrical signals into ultrasonic waves and performs signal processing.

Recently, the appearance of multivalued logic elements as signal processing elements has been awaited, but there is no such device that can be evaluated as a noteworthy device.

The object of the present invention is to provide a three-value logic element with high conversion efficiency, excellent electrical noise characteristics, and easy cascade connection.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a plan view showing an example of the electrode configuration of a logic element according to the present invention, and the electrodes on the back surface are shown by dotted lines.

That is, input-side interdigital electrodes A and B are interdigitally formed on one surface of a thin piezoelectric material to constitute an electrode pair. A surface electrode O is formed on the surface of the piezoelectric body so as to correspond to the electrode pair. The output side interdigital electrodes A' and B' and the output side electrode O' are formed on the piezoelectric body in the same configuration as the input side. The input side electrode O and the output side electrode O' are grounded, and the output side interdigital electrode
A′ and B′ constitute output terminals between the plane electrodes O′, respectively.

FIG. 2 is a block diagram showing signal processing of the present invention.

That is, the reference signal S is always input between the interdigital electrode A and the surface electrode O as a reference input terminal. Further, between the interdigital electrode B and the surface electrode O, either an input signal S, an input signal having a phase difference of 180 degrees from the input signal S, or a zero input is applied as an input terminal. On the output side, there are interdigital electrodes A′, B′ and a surface electrode.
The terminals between O′ serve as output terminals. In this case, when the input signal S is input to the input terminal, zero is output to the output terminal, when the input signal is input, 2S is output to the output terminal, and when the input signal is zero input, S is output.

The element having the configuration shown in Fig. 1 was constructed using a piezoelectric ceramic material 91A made by Tokyo Denki Kagaku Kogyo KK (polarized in the thickness direction) with a length of 40 mm, a width of 20 mm, and a thickness of 100 μm as the piezoelectric body, and a blind-shaped electrode was used. The electrode finger width and electrode spacing were both 75 μm, and the electrode was formed by vapor deposition of Al. When the output voltage was measured at a frequency of 12.8MHz, an output ratio of 0:3:5 was obtained. In other words, it constitutes a three-value logic element that can obtain output signals of three values 0:S:2S for input signals S and O.

In addition, when this device is connected in series, it is possible to match the phases of the input signal and output signal by making the distance between the input and output interdigital electrodes an integral multiple of the wavelength used, which is convenient. results.

In addition, as an ultrasonic transducer, a thin piezoelectric material (the thickness of which is less than the wavelength of the sound wave propagating through this substrate) is used as the substrate, and Lamb waves are utilized, and good results have been obtained. ,for example
When a piezoelectric thin film such as CdS or ZnO is provided on a non-piezoelectric substrate such as fused silica or glass, surface acoustic waves are used, and the same effect can be achieved in this case as well.

As described above, the present invention forms two pairs of interdigitated interdigitated electrodes on one surface of a thin piezoelectric material, and provides surface electrodes corresponding to the electrode pairs on the other surface of the piezoelectric material. The other of the electrode pair and the corresponding surface electrode are used as the output side, one of the interdigitated electrodes on the input side is used as a reference signal input end, and the other of the interdigitated electrodes on the input side is used as the reference signal input terminal. An ultrasonic logic element characterized by having in-phase, reverse-phase, and zero inputs as input ends for receiving input signals, and output ends between the interdigital electrode and the surface electrode on the output side, It is an excellent invention as it has excellent fluctuation efficiency, has a multi-value logic function, is resistant to noise because it has a filter function, and is easy to manufacture.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of a transducer of a logic element according to the present invention. FIG. 2 is a block diagram of the logic element of the present invention.

Claims (1)

[Claims] 1. Two pairs of interdigitated interdigitated electrodes are formed on one surface of a thin plate piezoelectric material whose propagating waves are Lamb waves, and a surface electrode is provided on the other surface of the piezoelectric material corresponding to the electrode pairs. are established respectively,
One of the electrode pairs and the corresponding surface electrode are used as the input side, the other of the electrode pair and the corresponding surface electrode are used as the output side, and a reference signal is input between one of the interdigitated electrodes on the input side and the surface electrode. The other side of the interdigital electrode on the input side and the surface electrode are used as an input signal with the same phase, opposite phase, and zero input as the reference signal, and the interdigital electrode on the output side and the corresponding surface. An ultrasonic logic element characterized by having output ends between the electrodes.