Abstract
The author has developed a thin film thermo-couple made by evaporating process in combination with a D. C. galvanometer to function as a detector or a device for measuring intensity of sound field. The author calculated the temperature rise of the thermo-couple assuming that the mechanism is a kind of hysteresis loss caused by the delay of alternating heat conduction between air medium and rigid surface in analogy to Dr. J. Saneyoshi's theory on the heat conduction damping of pulsating gas bubbles which resonate to ultrasonic wave in liquid. It is proved that the value of temperature rise measured by the thermo-couple is coincident with the value theoretically calculated. The temperature rise is proportional to the square of the sound pressure and to the square root of the sound frequency according to this theory. The fact that this detector has the same characters is also ascertained by this experiment.
