| 摘要 |
PURPOSE:To detect temperature by using a surface acoustic wave element for an oscillator whose oscillation frequency depends upon temperature, fitting it to a fitting body by using a flexible member, and radiating a radio wave in air and receiving the radio wave to detect the oscillation frequency. CONSTITUTION:An amplifier 14 is connected to the surface acoustic wave element 11 provided with a couple of transducers 13a and 13b on a piezoelectric substrate 12 to constitute the oscillator 15. The substrate 12 uses a material with a large temperature coefficient such as lithium niobate. A solar battery 16 is used and an antenna and a lead line 17 are connected mutually. Thus the transmission side is constituted, and a reception side is provided with a receiver 18 and a counter 19 which measures its frequency. The oscillator 15 operates by being supplied with electric power from the solar battery 16. The oscillation frequency of the oscillator 15 varies with temperature greatly and its frequency is counted by a counter 19 to easily know the temperature. Consequently, the temperature of a moving body or rotating body is detected accurately, precisely, and stably with the relatively simple constitution. |
