Switchable pattern illuminator via liquid crystal geometric phase microlens array

We propose a novel 2-in-1 pattern projector, which consists of a Dot projector and an LC diffuser. The LC diffuser is made of switchable Microlens Arrays (MLA) based on geometric phase. The LC diffuser can switch between "no lens power" and "MLA" mode. In "no lens power" mode, the Dot pattern is not affected by the LC diffuser. In "MLA" mode, the focused Dot pattern is "blurred" by the MLA, which generates the Flood pattern. The eigen mode of geometric phase MLA is carefully designed to achieve polarizer free modulation. We implement this novel modulation concepts with the world smallest and 1st ever reflowable LC cell. We made a record of 3x3mm LC cell with our in-house IJP system. The optical efficiency is over 95%, and the switching time is less than 5ms.