Diffractive optical elements for implementing spatial demultiplexing and spectral synthesizing simultaneously

Diffractive optical elements (DOEs) are designed for implementing spatial demultiplexing and spectral synthesizing simultaneously by using conjugate gradient optimization algorithm. Three different design cases for the spectrum window of the optical communication: three discrete spectral segments in one direction, two discrete spectral segments in two directions, and three discrete spectral segments in three directions, are implemented. The numerical simulations indicate that the designed multi-functional DOEs can successfully generate desired spectra at predesigned directions. These designs can provide a useful information for designing the wavelength division multiplexer and the arrayed waveguide grating in various optical systems.