Phase-difference-driven imaging based on a dual-layer stacking liquid-crystal microlenses with different array scale and basic microhole-shaped electrode

This paper presents a method for effectively constructing some featured light-fields by dual-layered stacking liquid-crystal (LC) microlenses (DSLCM) with different array scales and the structural sizes of microhole-shaped electrodes. Compared with conventional LC microlenses for adjusting the focal length solely via signal-voltage amplitude, the proposed DSLCM achieves a rapid imaging-mode switching and a dynamic light-field modulation by only configuring the static or dynamic phase difference (PD) between two applied signal voltages in a range of 0°-360°. Two typical focuses in millimeter and sub-millimeter dimensions of the DSLCM are presented. A better microbeam focusing efficiency can be originated from a strong spatial electric-field interference through forming an adjusted PD between two signal voltages with the same frequency and different amplitudes. The PD-driven imaging strategy means a dual-mode imaging switch is electrical and a relatively wide dynamic zooming by only efficiently configuring the PD value.