Temperature-Modulated Polarized Light Microscopy

Abstract

Temperature-modulated polarized light microscopy means the optical microscopy technique with the hot-stage by which the sample temperature is modulated periodically or step-like. Basic techniques for the temperature-modulated polarized light microscopy are summarized. The hot-stage was constructed using heating through light to give heat-flow modulation to the sample. The thermometer was put on the place which the heat reaches later than the sample. An example of application of the techniques to the studies of the phase transition of n-C₃₆H₇₄ is described. The small crystal of n-C₃₆H₇₄ was observed in the rotator phase transition temperature region. In the temperature region, the rotator phase coexists with the solid phase (low-temperature ordered phase). The boundaries of the two phases move reversibly with the temperature change. The area change of the rotator phase can be described by the Debye relaxation. The relaxation time agrees well with that of the dynamic specific heat.