Computer-generated holographic diffuser for color blending considering divergent sources

An iterative algorithm for multiple incoming wavelengths considering divergent sources is proposed to design a computer-generated holographic diffuser (CGHD) with high light utilization efficiency and uniform color mixing. We modified the conventional G-S algorithm when its input wavefront is divergent and consists of more than one wavelength. This diffuser is designed according to the Fresnel diffraction theory and can uniformly spread the different input light at far field distribution. The amplitude transmittance of this CGHD is a constant, while the phase transmittance consists of multiple phase levels. An example of designed CGHD with two divergent wavefronts is illustrated and simulated. The proposed algorithm can be used to design diffractive device for applications such as wavefront multiplexing and demultiplexing.