Aligned Liquid Crystal Spatial Light Research Articles

Pixel-addressable phase calibration of spatial light modulators: a common-path phase-shifting interferometric microscopy approach

As spatial light modulators (SLMs) are becoming flexible and the preferred device for light steering, the SLM’s modulation calibration still remains challenging. No pixel-addressable measurement of the SLM has yet been practically implemented. We present a quantitative phase measurement and calibration method for a parallel aligned liquid crystal spatial light modulator (PAL-SLM) based on Pancharatnam phase-shifting interferometric microscopy. The pixel-wise phase of SLM can be detected from microscopic interference pattern formed from two orthogonally polarized light waves reflected off the PAL-SLM. The wave phase is modulated or non-modulated depending on its polarization direction parallel or orthogonal to the liquid crystal director. Owing to self-referencing common-path interferometric microscopic imaging, the proposed method is quite robust against environmental disturbance and enables a high-precision pixel-wise characterization of SLM.

High speed parallel aligned liquid crystal spatial light modulator operated at 180 Hz

We made a parallel aligned liquid crystal spatial light modulator (PAL-SLM) respond within 6 ms to meet requirements for a single-SLM color projection system. This was done by adjusting thicknesses of its optical addressing layer and its light modulating layer.

High speed parallel aligned liquid crystal spatial light modulator operated at 180 Hz

High speed parallel aligned liquid crystal spatial light modulator operated at 180 Hz