Low-noise high-efficiency double-phase hologram by multiplying a weight factor.

This Letter describes a method of generating a phase-only hologram, which improves the lack of diffraction efficiency and peripheral noise phenomenon, which is a problem of the existing double-phase hologram (DPH) method. The proposed weight factor DPH method can be obtained by a simple matrix operation, so there is no need for additional computing power. The optimal weight factor value depends on the image size, so we have found the optimal value for each image size. The numerical simulation and optical experiments were conducted to compare the images generated using the proposed weigh factor DPH method, the existing DPH method, and the random phase method. The peak signal-to-noise ratio of the images obtained through the proposed weight factor is improved by 14.6% compared to the existing DPH.