Development of Reflection Objective-Employed Collinear Mode-mismatched Thermal Lens Microscope

Abstract

A reflection objective-employed collinear thermal lens microscope (roco-TLM) is developed in which a reflection objective lens is used for collinearly focusing, in a mode-mismatched configuration, both an excitation laser beam at 260 nm and a probe laser beam at 632 nm. With the microscope, unsymmetrical distortions of a thermal lens image obtained with a reflection objective were reduced. The cause of the diffraction pattern in a thermal lens image observed with the roco-TLM is discussed as well.