| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an abnormal state detection method capable of detecting an abnormal state of a detected object at a low cost, high sensitivity and high accuracy using a sheet-like piezoelectric sensor, and the sheet-like piezoelectric sensor used for that method. <P>SOLUTION: The abnormal state detection method comprises a step of sticking and fixing the sheet-like piezoelectric sensor 1 having flexibility to the detected object, a step of detecting acoustic vibration from the detected object with the piezoelectric sensor, and a step of determining the abnormal state of the detected object based on a detected signal of the acoustic vibration. In this piezoelectric sensor, as a piezoelectric layer 4, a thin film mainly made of one piezoelectric metal compound selected from aluminum nitride, gallium nitride, indium nitride, zinc oxide, and lithium niobate is formed on a sheet-like substrate 3 having flexibility. <P>COPYRIGHT: (C)2007,JPO&INPIT |
