ELECTROOPTIC METHOD AND APPARATUS USING LIQUID CRYSTAL

摘要

An electro-optical method and apparatus uses liquid crystals. The method includes the step of filling a space between two parallel transparent plates with a material which comprises molecules having nematic properties, the structure of the molecules initially defining a substantially rectilinear nematic director perpendicular to the plates. A structure is then conferred on the material defining a second nematic director curved at least once in a plane perpendicular to the plate by application of a high frequency electrical field to the material, such that the second nematic director arrives substantially perpendicularly at at least one of the two plates. A twist is imparted to the second nematic director along a component at right angles to said plane perpendicular to the plates to impart a twist in the second nematic director. Light is caused to arrive with an incidence substantially at right angles to one of the plates to pass through the material, a rotation of polarization of the light, at an outlet from the plates, depending on the twist imparted to the second nematic director.