Andrei Y. Smuk

Direct laser writing of diffractive optics in glass

Low-power lasers and a novel thermal expansion process in semiconductor-doped glasses are used to fabricate diffractive optical elements.

Direct laser fabrication of dense microlens arrays in semiconductor-doped glass

A direct laser writing technique in semiconductor-doped glasses is used to fabricate microlens arrays with fill factors exceeding the close-packing limit for circular microlenses. This is achieved by both structural and thermal interactions between adjacent lenses during fabrication, which result in the formation of microlenses shaped in accordance with the translational symmetry of the array. The effect of nearest-neighbor interaction on various time scales is studied and shown to be critical to the distortions observed.

Two Wave Mixing in Holographic Polymer Dispersed Liquid Crystal (H-PDLC) Formation

Abstract The intensity of transmitted laser beams is monitored during the holographic formation of polymer dispersed liquid crystal gratings. Significant attenuation of the total transmitted intensity is experienced after brief illumination. In most cases the attenuation increases for several seconds before reaching a steady-state value. Analysis of the individual beam intensities reveals energy exchange between the beams in a nonlinear two-wave mixing process. This information is analyzed to help gain insight into the complex dynamics of H-PDLC formation.

Selective etching in laser written semiconductor-doped glasses

Semiconductor-doped glasses exposed to CW laser radiation exhibit selective chemical etching. The effect can be used to produce topographic features with negative relief, high aspect ratio, and submicron size for a number of applications.