Low-tilt-angle nematic alignment compatible with frit sealing

Uniform homogeneous alignment of nematic liquid crystals with low (<5°) tilt angles has been achieved by combining evaporated SiO layers at two angles of incidence. The first evaporation is performed at an incidence angle of 5°. The substrate is then rotated 90° about its normal and the second evaporation is performed at an incidence angle of 30°. The alignment tilt angle depends on the thickness of the second layer relative to that of the first. Low tilt angles are confirmed by observation of interference-type conoscopic figures.