Abstract

Recently the electroclinic effect in chiral smectic A (Sm A) liquid crystals has been the subject of increased study because of its potential for spatial light modulators with fast response and greyscale operation. For this application, a large contrast ratio is desirable and often essential. However, it has been observed¹ that, when smectic A liquid crystals are subjected to an electric field and viewed between crossed polarizers, they exhibit distinctive periodic stripe domains due to a voltage deformation (kink) of the bookshelf geometry.² The molecular alignment is reported to alternate between stripes, reducing the contrast ratio and imposing performance limitations on electrooptic devices based on these materials. In this investigation, we report spatially resolved measurements on a smectic A liquid crystal, performed using a novel technique to probe the optical properties with micron resolution. The effect of the stripe formation on the electrooptic properties of the Sm A liquid crystal KN125 is investigated.

© 1995 Optical Society of America