| 摘要 |
PROBLEM TO BE SOLVED: To provide a liquid level meter which is simple and low-cost and has high reliability by utilizing ultrasonic waves. SOLUTION: A piezoelectric film 16 is made adhere to the opposite surface to one surface of an ultrasonic wave transmitting plate-like member 12 such as a plastic plate or the like that comes into contact with a liquid 10 to be measured to emit an ultrasonic wave, and an echo different in magnitude depending on whether one surface of the plate-like member 12 comes into contact with the liquid 10 or not is detected to detect and measure the liquid level. The plate-like member 12 may be a wall of a liquid 10 container and a wall of an enclosure dipped in the liquid 10. |
