Electro-Optical Effects of a Small-Pitch Blue-Phase System

Abstract

A system which shows a relatively large blue-phase range is investigated. Owing to the small value of the cholesteric pitch the blue-phase shows no Bragg-reflections in visible light. Nevertheless, electric-field induced birefringence shows quite large values. The response times are a few tens of microseconds below 10°C. Crude estimates of the effects lead to values reasonably close to the experimental ones. Zero voltage birefringence effects are encountered, field induced and slowly decaying at higher temperatures and surface induced at lower temperatures where a uniaxial phase appears to be stable.