Abstract

Commercially available polymer dispersed liquid crystal (PDLC) systems act as scatter mode devices in which discrete liquid crystal droplets (whose dimensions are greater than λ/10) scatter incident light when the liquid crystal units are randomly aligned, but when aligned by an applied electric field become transmissive¹. The reduced scattering is due to two non-competitive effects: a reduction in refractive index to match that of the host polymer, and an alignment of the liquid crystal units. The current work has developed a system where the initial size of the discrete liquid crystal droplets is below the visible light scattering limit. This hybrid PDLC system remains optically isotropic irrespective of the applied electric field strength. This novel nanocomposite has been incorporated into etalon cavities where it is utilised as an electrooptic spacer layer, thus enabling a frequency tuneable filter to be realised.

© 1998 Optical Society of America