Liquid-Crystal Devices and Waveplates for light controlling

The main characteristics of liquid crystal devices (LCDs) are discussed with reference to various technologies. Principles of operation of some LCDs for light radiation parameters controlling are described. Two advanced waveplates are demonstrated: cycloidal diffractive waveplates (DWPs) and DWPs with axial symmetry. Achievements in the technology of producing highquality DWPs with practically 100% efficiency over a large area advance the prospects and the concepts of polarizer-free LCDs. These gratings could be used for beams combining and polarizing with high productivity. Observations prove the feasibility of new generation high-efficiency diffractive optical components, which are most promising for infrared and high-power applications owing to their enhanced transparency and reduced thermal effects in thin material layers.