Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 03, 2023 - September 06, 2023
This report deals with a method for comprehending real contact situation by measuring complex refractive index in contact surface. For the contact surface where spherical samples were pressed against a glass plane, the distribution of complex refractive index was measured experimentally and was estimated by Hertz contact theory and the optical model in which the multiple reflections inside the gap between surfaces were considered. For the BK7 glass lens sample, the measured index was equal to the physical property value in the contact and non-contact region both in air and in water and was accounted successfully for by the multiple interface model in the region where the index slowly changed. For the silicon lens sample, the measured index was not equal to the physical property value but showed a proper value in the contact region both in air and in water. From the above it is suggested that this method enables identifying sample material as well as judging contact situation.
