A self-healing ferroelectric liquid crystal electro-optic shutter based on vertical surface-relief grating alignment

Ferroelectric liquid crystals remain of interest for display and spatial light modulators because they exhibit significantly faster optical response times than nematics. However, smectic layers are sensitive to shock-induced flow and are usually permanently displaced once a well-aligned sample is disrupted, rendering such devices inoperable. We introduce a vertical alignment geometry combined with a surface-relief grating to control both the smectic layer and director orientations. This mode undergoes "self-healing" of the smectic layers after disruption by shock-induced flow. Sub-millisecond switching between optically distinct states is demonstrated using in-plane electric fields. Self-healing occurs within a second after being disrupted by shock, wherein both the layer and director realign without additional external stimulus. The route to material improvements for optimised devices is discussed, promising faster spatial light modulators for high-speed adaptive optics, micro-displays for virtual/augmented reality and telecommunications with inherent shock stability. Ferroelectric liquid crystals (FLCs) have faster optical response times than nematic crystals, but they are also less robust to external shock. Here the authors develop an FLC geometry that reduces the sensitivity to external disruption through self-healing, making them more stable for applications.