| 摘要 |
PURPOSE:To provide direct digital processing by a compact simple construction wherein two vibrating regions are formed on a piezo vibrator and, as a back electrode, a material whose electric resistance changes in response to an object to be detected is used to detect the object based on the difference in oscillating frequency between the vibrating regions. CONSTITUTION:There is shown a crystal vibrator P as a piezo vibrator and one of the surfaces is provided with two pairs of single side driving electrodes E11, E12 and E21, E22, the electrodes forming vibrating regions A1, A2, respectively. The other surface of the crystal vibrator P is used as a free surface, whereas back electrodes B1, B2 are formed on the back surfaces of the electrodes E11, E12 and E21, E22. Then an oscillation circuit OS1 is formed by connecting a C-MMOS invertor V1, a resistor R1 and capacitors C11, C12 to the electrodes E11, E12, whereas an oscillation circuit OS2 is formed by connecting a C-MOS invertor V2, a resistor V2 and capacitors C21, C22 to the electrodes E21, E22. There is also shown a mixer M in the Figure. |
