Laser speckle reduction using polymer-stabilized liquid crystals doped with Ag nanowires

Miniaturized and pure static devices are expected to be used in laser-imaging systems for speckle reduction. In this study, a pure static device based on polymer-stabilized liquid crystal (PSLC) doped with Ag nanowires was developed to effectively suppress laser speckles. The concentrations of the polymer and Ag nanowires in the PSLC were optimized, and then the PSLC devices were fabricated. A measurement system was set up to characterize the electro-optical properties of the fabricated PSLC devices. Subsequently, a laser projection system was built to demonstrate the speckle-reduction performance. Moreover, the degree of scattering and response time of the developed PSLC devices were investigated and discussed. A PSLC doped with 0.02 wt% Ag nanowires and 3 wt% polymer having a device size of 2 x 2 x 0.1 cm3 was demonstrated to produce a speckle-reduction efficiency of 51.4 % under very low driving voltages. The experimental results verified effectiveness and superiority of the developed speckle reduction method based on PSLC doped with Ag nanowires.