High damage threshold liquid crystal binary mask for laser beam shaping

Rewriteable Photoalignment of Liquid Crystals as a Route to High-Laser-Damage- Threshold Active Beam Shapers

The fabrication of rewriteable liquid crystal (LC) cells using high-damage-threshold photoswitchable azobenzene materials has been investigated as a route to all-optical active beam shapers. Beam shapers are used to modulate the intensity profile of OMEGA EP's petawatt-peak-power laser beams. All-optical photoswitchable beam shapers would allow intensity profile tailoring to occur at higher-flu...

Liquid Crystal Beam Shaping Devices Incorporating Coumarin-Based Photoalignment Layers

1. Abstract Liquid crystal (LC) devices incorporating photosensitive polymers based on coumarin were investigated for laser beam shaping applications. Presently, the OMEGA EP laser system uses pixelated metal beam shaping devices, though their relatively low damage threshold (approximately 0.2 J/cm 2) makes them poor options for long-term usage. LC devices have the major advantages of a much hi...

Nematic Liquid Crystal Spatial Light Modulators for Laser Beam Steering

High-precision laser beam shaping using a binary-amplitude spatial light modulator.

We have achieved high-precision laser beam shaping by using a binary-amplitude spatial light modulator, a digital micromirror device (DMD), followed by an imaging telescope that contains a pinhole low-pass filter (LPF). An error diffusion algorithm was used to design the initial DMD pixel pattern based on the measured input beam profile. This pattern was iteratively refined by simulating the op...

Crystal-liquid crystal binary phase diagrams.

We propose a new theoretical scheme for the binary phase diagrams of crystal-liquid crystal mixtures by a combination of a phase field model of solidification, the Flory-Huggins theory for liquid-liquid mixing and Maier-Saupe-McMillan (FH-MSM) model for nematic and smectic liquid crystal orderings. The phase field theory describes the crystal phase transition of anisotropic organic crystal and/...