Single‐step exposure for two‐dimensional electrically‐tuneable diffraction grating based on polymer dispersed liquid crystal

The two‐dimensional (2D) electrically tuneable grating exhibits a bright future in the fields of optics and communication. A 2D grating based on a polymer‐dispersed liquid crystal (PDLC) with good electro‐optical (E‐O) properties was fabricated through a single‐step exposure method. The E‐O behaviour was measured and the morphology of the grating observed using polarising optical microscopy (POM) and atom force microscopy (AFM). In addition, a 2D diffraction model and photopolymerisation dynamics model are presented to evaluate the E‐O properties and morphology of the grating. All results obtained from the model show good agreement with experimental data. These results indicate that the morphologies are fairly good when the intensity ratio of pair L and pair K, labelled in the experimental setup, was 1:1.