Differential Conoscopy: Local Birefringence and Molecular Orientation in the Liquid Crystals

Abstract

A new experimental technique of observation and quantitative characterization of interference states in polarizing light is proposed. It permits the determination of the main optical features of the heterogeneous media, namely birefringence, rotatory power, biaxiality…etc, even of the microdomains. The method consists in superposition of unknown interference state and a standard interference state which presents axial symmetry, and permits observation of extinction zones.

Key Words:

• conoscopy
• birefringence
• ring
• extinction