| 摘要 |
PURPOSE:To enhance measurement accuracy, by instantaneously irradiating one face of a sample with a radiation having axially symmetrical intensity distribution, and observing a length of time required for temp. of the other face of said sample to reach 1/2 of the max. temp. and its prescribed ratio. CONSTITUTION:One face of a disc-shaped sample 1 having thickness (l) and radius (a) is instantaneously irradiated with an intense radiation 2 such as laser beams, and temp. theta is observed with a thermocouple junction 3 attached to the center of the other face of the sample. The thermal diffusion rate alpha of the sample is obtained as alpha=Kl<2>/(t1/2)0, where a time length t necessary for the temp. theta to reach 1/2 of the max. value thetam is exprssed as (t1/2)0. When the radiation has axially symmetrical intensity distribution with respect to the axis 5 of the sample 1, accurate measurement can be made by correcting the proportion constant K, permitting measuring accuracy to be enhanced. |
