Limits of scalar diffraction theory for multilayer diffractive optical elements

We presented the optimal surface relief heights of multilayer diffractive optical elements (MLDOEs) with the extended scalar diffraction theory. Comparisons of diffraction efficiency and polychromatic integral diffraction efficiency (PIDE) with different periods are described and simulated with extended scalar diffraction theory and scalar diffraction theory. The results show that the limits of scalar diffraction theory for MLDOEs and the minimum zone width of MLDOEs is different from that of traditional single-layer diffractive optical elements.