An O-plate compensator is manufactured by dissolving a polyimide polymer material incorporating a plurality of bulky side-chain groups in a first solvent to form a first solution, applying the first solution to a substrate, evaporating the first solvent to form an alignment layer, buffing the alignment layer, dissolving a polymerizable liquid crystal material in a second solvent to form a second solution, applying the second solution to the alignment layer, evaporating the second solvent to form a thin film of polymerizable liquid crystal material (with a nematic phase, an alignment-layer interface having a liquid crystal pretilt angle of between approximately 25 and 65 degrees, and an air interface), adjusting the temperature of the thin film to obtain a uniform specified orientation of a director of the thin film, and polymerizing the thin film with ultraviolet radiation to achieve a liquid crystal pretilt angle of between approximately 25 and 65 degrees at the air interface.