Control of liquid crystal alignment in an optical device

A method is provided that allows simultaneous control of macroscopic azimuthal and zenithal liquid crystal alignment (phi, theta) across a liquid crystal layer by controlling the area ratios between first, second and third different types of alignment region (T 1 , T 2 , T 3 ) in a patterned alignment layer, the three different types of alignment region (T 1 , T 2 , T 3 ) tending to induce liquid crystal alignment in the liquid crystal layer in three different respective, non-coplanar, principal orientations (z, x, y). In the illustrated example, the first type of alignment region (T 1 ) tends to induce substantially homeotropic alignment (in the z direction) and the second and third types of alignment region (T 2 , T 3 ) tend to induce substantially planar alignment in different, orthogonal, principal orientations (in the x and y directions). Control of macroscopic zenithal liquid crystal alignment (theta) is achieved by controlling the area ratios between the homeotropic (T 1 ) and planar region types (T 2 , T 3 ), and control of macroscopic azimuthal liquid crystal alignment (phi) is achieved by controlling the area ratio between the two planar region types (T 2 , T 3 ).