APPARATUS FOR MEASURING SCATTERING OF LIGHT

摘要

PURPOSE:To measure the scattering of light containing a light scattering component having a large scattering angle with high sensitivity and high accuracy, by irradiating intermittent light and absorbing the scattered light thereof to convert the same to heat energy and subsequently detecting the same as an electric signal by a piezoelectric element. CONSTITUTION:Light incident as shown by the arrow is converted to intermittent irradiation beam 2 by a chopper 10 and this beam is condensed by a lens 13 to irradiate matter 1 to be inspected. Scattered light 3 is intermittently generated from the surface of the matter 1 to be inspected according to the physical properties of the matter 1 to be inspected and absorbed by an absorbing substance 7 to be converted to heat energy. An elastic wave is generated by said heat energy and detected by an elastic wave detection means 1 comprising a piezoelectric element and the electric signal thereof is sent to a lock-in amplifier 12 and subjected to frequency synchronous detection on the bases of the reference signal from the chopper 10 and the result thereof is recorded on a recorder 14.