title: Broadband optical switch based on liquid crystal dynamic scattering.
abstract: This work demonstrates a novel broadband optical switch, based on dynamic-scattering effect in liquid crystals (LCs). Dynamic-scattering-mode technology was developed for display applications over four decades ago, but was displaced in favor of the twisted-nematic LCs. However, with the recent development of more stable LCs, dynamic scattering provides advantages over other technologies for optical switching. We demonstrate broadband polarization-insensitive attenuation of light directly passing thought the cell by 4 to 5 orders of magnitude at 633 nm. The attenuation is accomplished by light scattering to higher angles. Switching times of 150 μs to 10% transmission have been demonstrated. No degradation of devices is found after hundreds of switching cycles. The light-rejection mechanism is due to scattering, induced by disruption of LC director orientation with dopant ion motion with an applied electric field. Angular dependence of scattering is characterized as a function of bias voltage.
authors.forename: M W
authors.initials: MW
authors.lastname: Geis
authors.forename: P J
authors.initials: PJ
authors.lastname: Bos
authors.forename: V
authors.initials: V
authors.lastname: Liberman
authors.forename: M
authors.initials: M
authors.lastname: Rothschild