High-resolution and programmable fabrication of liquid crystal polymer microactuators via femtosecond laser direct writing

Photodeformable liquid crystal polymers (LCPs) that undergo a geometric deformation excited by the light have aroused an increasing interest. The fabrication of LCP actuators into microscale is important for smart and multifunctional applications due to their advantages of compact size, rapid response, remote controllability, high integration and versatile functionality. Here, a femtosecond laser direct writing method is developed for high resolution and programmable fabrication of arbitrarily patterned photochemical effect and photothermal effect LCP microactuators. Through optimization of laser machining parameters, a minimum effective size of ∼35 µm as well as an average heat-affected zone (HAZ) of ∼8 µm of LCP microstructures are achieved. The light-responsive behaviors of the prepared LCP microstructures with different shape and cutting direction are systemically investigated through irradiation of corresponding wavelength driving light. Finally, we demonstrate the applications of LCP microstructures as a photocontrol switch and micromirror system.