Phase-modulation Method Using a Dual In-plane-switching Liquid-crystal Panel

We propose a phase-modulation method with a simple combination of commercial-level dual inplane-switching (IPS)-mode liquid-crystal (LC) panels. IPS-mode liquid crystals enable phase modulation using their half-wave retardation changes related to molecular rotation. Therefore, the phase retardation is performed by electric field while preserving the polarization ellipticity of the incident polarization state. While this level of phase modulation is adequate for intensity modulation in conventional LC panels, it falls short for the phase modulation required to realize holographic displays. Our proposed system stacks IPS-mode LC panels and compensates polarization state to increase the phasemodulation range in proportion to the rotation angle of the liquid crystal, while preserving the output polarization. We evaluate the phase-modulation performance of the proposed configuration through interferometry, optically reconstructed holograms to confirm conjugate noise reduction, and multidepth implementation capabilities, thereby validating the potential of a cost-effective commercial IPS-mode LC panel.