A Twyman-Green interferometer is used to measure the phase induced by a liquid-crystal spatial light modulator (LC-SLM) via spatial-carrier phase measurement methods in order to characterize the phase response as a function of applied voltage. With the phase response characterized, the LC-SLM can be operated in a closed-loop adaptive optics system. Four separate phase unwrapping algorithms are ...

Accurate modeling of a high-resolution, liquid-crystal-based, optical phased array (OPA) is demonstrated. The modeling method is extendable to cases where the array element size is close to the wavelength of light. This is accomplished through calculating an equilibrium liquid-crystal (LC) director field that takes into account the fringing electric fields in LC OPAs with small array elements a...

We report a type of high-speed microcell polarimeter that utilizes microelectrodes, liquid-crystal films, and ultrathin high-contrast polarizers, all integrated between the tips of two optical fibers. When combined with optimized nematic liquid-crystal materials, this compact (2.5 cm x 0.5 cm x 0.5 cm) device offers excellent optical properties and continuous, high-speed operation at > 2 kHz wi...

We design and assess a one-dimensional photonic crystal slab fabricated by preferential etching of a silicon-on-insulator substrate. The etched grooves are considered to be infiltrated by a highly-birefringent nematic liquid crystalline material. A detailed analysis of the nematic director response within the grooves is presented. We investigate different configurations and demonstrate large ba...

We report an electrical-field switched color device using a polymer-stabilized blue-phase (PSBP) liquid crystal in which the Bragg-reflected color of the blue phase (BP) can be switched to reflect a second color. The phase-separated three-dimensional polymer network transcribes the cubic structure of a BP liquid crystal and restrains the deformation of cubic lattice by the external electric fie...

We study nematic liquid crystal configurations in a prototype bistable device the Post Aligned Bistable Nematic (PABN) cell [9]. Working within the Oseen-Frank continuum model, we describe the liquid crystal configuration by a unit-vector field n, in a model version of the PABN cell. Firstly, we identify four distinct topologies in this geometry. We explicitly construct trial configurations wit...

We study nematic liquid crystal configurations in a prototype bistable device the Post Aligned Bistable Nematic (PABN) cell [9]. Working within the Oseen-Frank continuum model, we describe the liquid crystal configuration by a unit-vector field n, in a model version of the PABN cell. Firstly, we identify four distinct topologies in this geometry. We explicitly construct trial configurations wit...

A transmission-type nonmechanical multiple-angle beam-steering device that uses liquid-crystal blazed grating has been developed. Sixteen steering angles with a contrast ratio of 18 has been demonstrated. A detailed analysis of the liquid-crystal and poly(methyl methacrylate) blazed-grating deflector was carried out to provide guidance during the deflector's development. A manufacturing offset ...

In this paper, the physics that determines the performance limits of a diffractive optical element based on a liquid-crystal ͑LC͒ optical phased array ͑OPA͒ is investigated by numerical modeling. The influence of the fringing electric fields, the LC material properties, and the voltage optimization process is discussed. General design issues related to the LC OPA configuration, the diffraction angl...

The difference between the equilibrium and switching d/p ratio of a bistable twisted nematic ͑BTN͒ liquid crystal display is shown by computer simulation. It is clearly indicated that the optimized d/p ratio has to be determined by the switching rather than equilibrium d/p ratio. It is also shown that the switching d/p ratio is related not only to the pre-tilt angle, but also to liquid crystal vi...