Differential heterodyne optical probe using a Zeeman-laser

Optical scanning microscopy has been widely used to detect light scattering particles or lattice defects in crystals. On the other hand, optical heterodyne technique using a local heterodyne optical system has been adopted by some authors for aberration free image formation. In this study we developed a light scattering microscope with a differential heterodyne optical system simplified in its configuration by the use of a Zeeman laser, and the feasibility of the system was examined experimentally. Differential heterodyne optical system has the advantage of gaining strong scattered light, simple congiguration, and applicability to the detection of other kinds of physical quantities such as acoustic waves and optically induced electric currents.