Passive electro=optic liq. crystal display cell - where silicon oxide layer aligns liq. crystal molecules to produce sharp contrast

摘要

The cell contains a nematic, spiral-shaped liq. crystal between two glass plates. At least one of the plates is coated with a layer (a) to which the liq. crystal molecules adhere at an angle of zero; and parts of layer (a) are covered by an aligning layer (b) on which the liq. crystal molecules form an anchoring angle of 15 degrees, and leaving bare zones (a1). The result is that the liq. crystal molecules adhere to the plate at an angle below 10 degrees and with average angle on both plates below 5 degrees. Layer (b) pref. has ave. thickness below 70 angstrom, and has an angle of incidence on layer (a) of ca. 5 degrees. The contrast has a threshold value which depends on the voltage applied to some of the alphanumeric electrodes, so that a clear and sharp visual display is obtd.