Tunable Patterned Blue Phase Liquid Crystals Based on Lithographic Process Technology

Abstract Spatial control of memory effects in soft matter photonic crystals is a key challenge for reconfigurable optics. Here, a patterned blue phase liquid crystal (BPLC) device that exhibits localized, electrically‐driven bistability is demonstrated, achieved through a cost‐efficient photolithographic fabrication method. The innovative dual‐alignment design, utilizing two distinct commercial alignment materials, ensures strong anchoring stability while reducing fabrication complexity. This architecture yields regions with markedly different electro‐optic responses: hybrid‐aligned areas support conventional analog modulation, while vertically‐aligned regions within the BPII phase exhibit a non‐volatile memory effect. This enables switching between a high‐contrast patterned state and a uniform reflective state. Furthermore, a repetitively applied field (RAF) protocol is introduced mitigates field‐induced crystal degradation in the BPI phase, thereby enhancing device longevity and reliability. By enabling spatially programmable bistability across multiple liquid‐crystal phases, the approach opens new pathways for advanced photonic systems that integrate memory and display functionalities in a single platform.