Conjugate symmetric extension Fourier computer-generated holography with controllable reconstruction focus

A conjugate symmetric extension Fourier computer-generated holography algorithm with controllable reconstruction focus is proposed. The real function can be directly generated by the inverse Fourier transform of the target object after conjugating symmetric extension. Subsequently, it is mapped to 0–2π linearly and superimposed with a quadratic phase term that carries the reconstruction focus to obtain a phase-only hologram that contains the amplitude, phase and reconstruction focus information of the target object. Numerical reconstruction and optical reconstruction results show that the target object can have a good reconstruction effect at a given distance. The algorithm contains only one inverse Fourier transform, which improves the efficiency of holographic coding significantly and can be used for a real-time 3D holographic display.