PROBLEM TO BE SOLVED: To obtain a measuring apparatus by which the thermophysical property in a very small region on the surface of a sample is measured with high spatial resolution.
SOLUTION: A metal thin film is formed on the surface of a sample 3. In order to heat the surface of the sample, a laser beam 5 for heating, which is AC-modulated by a modulator 8 and a laser beam 6 for temperature measurement, with which the surface of the sample is irradiated are condensed in nearly the same position on the surface of the sample through a micro-optical system 4. The reflected light of the laser beam for temperature measurement, at this time is detected. On the basis of the reflected light of the laser beam for temperature measurement, a change in the temperature of the surface of the sample is detected, its phase delay and its relative intensity are measured, and the thermophysical property value in a very small region of the sample is calculated. When the sample is moved two-dimensionally, the two-dimensional distribution of a local thermophysical property value can be found.