Submillisecond-response liquid-crystal-on-silicon for augmented reality displays

We report a new nematic liquid crystal (LC) mixture with an extremely low rotational viscosity (γ₁ = 38 mPa·s @ 20.7 °C), relatively high birefringence (Δn = 0.159 @ 550 nm), and moderate dielectric anisotropy (Δε = 2.86 @ 25 °C). An average submillisecond response time is achieved at room temperature without overdrive and undershoot voltages when it is employed in a reflective liquid-crystal cell. Such a fast response time enables a 1 kHz field-sequential color (FSC) field rate, which not only triples the optical efficiency and resolution density but also mitigates image blur and color breakup. Furthermore, the required cell gap of 1.34 µm remains manageable for acheiving a good mass-production yield. This LC holds great potential for the emerging artificial intelligence (AI)-powered augmented reality (AR) glasses.