A tunable liquid-crystal microlens with hybrid alignment

Abstract

A tunable liquid-crystal microlens with hybrid alignment was fabricated using micro-imprinting technology. The imprinted hybrid alignment, which was surrounded by homogeneous (homeotropic) alignment, resulted in spatial refractive-index distribution of liquid-crystal molecules in the microlens. With different hybrid-alignment configurations, the microlens functioned either as a convex or concave lens. The focal length of the microlens was electrically controlled at applied voltages of less than 4V. The focal length was adjusted from 7.8 to 8.6mm and from -10 to -35mm for a convex and a concave lens, respectively. The rising response time was 0.5s, and the falling response time was 5s. © 2006 IOP Publishing Ltd.