Ultrawide-view Achromatic Circular Polarization Dynamic Converter Using an Easy-to-integrate Multi-Layer Structure.

What we believe to be a novel integrated circular polarization dynamic converter (CPDC) is proposed based on the four-layer mirror symmetry structure. By designing the twisted structure and rearranging the orientation direction of liquid crystal molecules for each layer, the application wavelength range could be broadened. For the viewing angle expansion, negative birefringent films are selected to compensate for the retardation deviation under oblique incidence. Finally, the particle swarm algorithm is used to optimize the whole configuration, and the polarization conversion efficiency calculated by the finite element method (FEM) can achieve 90% in the wavelength range from 320 nm to 800 nm at an ultrawide view of 160 degrees. Compared with traditionally active liquid crystal waveplates, the design has potential advantages in both wavelength and field of view (FOV) and provides the possibility for the integrated and flimsy fabrication of devices.