Computer-generated holography using the generalized Van Cittert-Zernike Schell propagator.

We introduce a computer-generated holography system based on the theory of partial spatial coherence, simplifying the required optical setups and improving computational efficiency. The method utilizes the generalized Van Cittert-Zernike Schell (GVS) model to calculate the forward propagation of light emitted by a common mobile phone screen and reflected by a phase-only spatial light modulator at various propagation distances. An inverse problem is then solved using stochastic gradient descent optimization to obtain the intensity and phase holograms that produce the desired intensity images at different depths. We conduct a two-layer optimization validated through numerical and optical experiments. Using the GVS model, we report speed improvements of 15× and higher-quality numerical reconstructions over the reference method of compressive propagation with random wavefronts. Furthermore, we achieve numerical and optical 3D focus-defocus effects by optimizing a focal stack with 20 depth layers.