Phase retarders usually present a strong frequency dependence. We discuss the design
and characterization of a terahertz achromatic quarter-wave plate. This wave plate is made …

We report on a family of complex birefringent elements, called Multi-Twist Retarders (MTRs),
which offer remarkably effective control of broadband polarization transformation. MTRs …

Recently, diverse twisting structures have been discovered to be a potential approach to
design liquid crystal polarization gratings and lenses (LCPGs and LCPLs) with a high …

Photonic metamaterials combined with liquid crystals (LCs) for tunability is a great niche for
building miniature devices with high performance such as fast flat tunable lenses, tunable …

We report on lenses that operate over the visible wavelength band from 450 nm to beyond
700 nm, and other lenses that operate over a wide region in the near-infrared from 650 nm …

An optical element includes at least two stacked birefringent layers having respective local
optical axes that are rotated by respective twist angles over respective thicknesses of the at …

The wavelength dependence of phase retarders is considered as a challenge in different
applications such as polarimetric systems. A novel achromatic waveplate based on two …

A single layer retarder possessing negative dispersion (ND) of birefringence as well as wide
field-of-view (FOV) was long-term objective in optical science. We synthesized new guest …

A method of designing achromatic elliptical polarizers using a combination of multiple
birefringent waveplates is demonstrated. This approach has a simple geometric …

We suggest a method to obtain a negative dispersion (ND) of birefringence using a two-
dimensional self-organization of smectic liquid crystal (LC) and monomer molecules. The …