Phase-compensated encoding of kinoform

A phase-compensated encoding method is proposed in this paper for the design of phase-only optical element (also called kinoform). The proposed elements are surface relief plates, i.e. , phase-only elements, which are based on the concept of computer-generated masks fabricated by common etching processes. The new encoding method can reduce the reconstructed errors such as quantization error through multi-level phase compensations. The number of subcells of every encoded cell is determined by the requirement of error reduction in actual implementation. Computer simulation confirms that the proposed encoding scheme can produce reconstruction with higher signal-to-noise ratio, higher diffractive efficiency and better uniformity than conventional encoding methods.