| Popis: |
This article shows a fast continuous 2π geometrical phase modulator based on the dynamic optical axis rotation of the short-pitch Ferroelectric Liquid Crystal (FLC). A continuous multi-level (8-bit) phase modulation, fast switching time (< 250 μs at 2 kHz), low operating voltage (< 7 V), and high diffraction efficiency (> 77%) is achieved using defect-free Deformed Helix Ferroelectric Liquid Crystal (DHFLC) for the first time. We showed a minimum feature size of 1 µm without fringe field effect (FFE). We also developed a new FLC with a cone angle of ~85˚ and a way to provide compensated half-wave condition (HW) during the entire electro-optical operational range. As a result, we achieve both spatial and time modulation with high frequency (1/3 μm-1 and 4 kHz, respectively), which can be used in applications such as a real-time hologram and dynamic beam steering in Light Ranging and Detector (LiDAR). |
