Fidelity comparison of phase masks for hybrid imaging

A significantly increased defocus tolerance can be obtained by combining pupil phase-modulation with digital demodulation in a hybrid imaging system. Designing the optimal pupil phase-modulation is however not a trivial task. We show how hybrid imaging fidelity can be predicted and used to compare arbitrary phase-modulations. The evaluations of two anti-symmetric and a symmetric phase-modulation yield initial design values that can be used for the optimization of specific hybrid designs.