An interferometric method using a nematic liquid crystal phase grating has recently been developed for determining the sum of the flexoelectric coefficients, (e1 + e3) [C. Trabi, C. V. Brown, A. A. T. Smith and N. J. Mottram, Appl. Phys. Lett. 92, 223509 (2008)]. The switching response of the device can be simulated if the applied 0.2 Hz squarewave voltage in the nematic layer is modified so that it is enhanced by a reverse ion-field after each polarity reversal and then decays with time. This process has been investigated using measurements of the transient capacitance of a planar nematic layer to the same waveform.
- diffraction optical element
- nematic liquid crystals
- transient capacitance
Trabi, C. L., Smith, A. A. T., & Brown, C. V. (2009). Interferometric method for the measurement of the flexoelectric polarisation using nematic liquid crystal phase gratings. Molecular Crystals and Liquid Crystals, 509, 1120-1134. https://doi.org/10.1080/15421400903066125