Conversion of a polarization microscope into a Mueller matrix microscope. Application to the measurement of textile fibers

This work reports the conversion of a commercial polarization microscope (Zeiss Jenaval) into an automatized Mueller matrix microscope. A Mueller matrix measurement provides the value of all the optical properties of a specimen (linear dichroism, linear birefringence, circular dichroism etc.) at a specific wavelength. In contrast to traditional polarization microscopes, which use white light and crossed polarizers to generate colored interference patterns that are analyzed by the microscope user and give only semi-quantitative results, here we demonstrate that it is possible to convert a polarization microscope into a Mueller microscope by only adding two motorized rotating compensators into the optical path without altering the optics or other opto-mechanical elements of the microscope. To our knowledge this is the most compact, fast and handy Mueller microscope ever developed. The performance of this new Mueller matrix microscope is illustrated with some birefringence measurements on textile fibers.