Emile Johannes Karel Verstegen

Liquid crystal aberration compensation devices

The application of aberration compensation devices can support the trend to higher information densities in optical data storage. The information content of a disc may be increased while maintaining acceptable tolerance levels. For example, disc tilt dependence may require coma compensation, whereas double layer formats require spherical aberration compensation. Liquid crystals (LCs) can be successfully applied in such devices. The design of two practical implementations is discussed; a coma compensating LC-cell with special electrode-design for optimized tolerances w.r.t. decentering, and a lens made of photopolymerizable LC, which can be used to compensate for spherical aberration.