Fabrication of Hierarchical Micro/nano- Compound Eyes.

Abstract

Fabrication of a hierarchical macro-/micro-/nano- compound eye is presented in this paper. This bioinspired compound (BIC) eye is obtained by an integrated manufacturing technology that combines (i) nano-imprinting, (ii) picosecond laser swelling, and (iii) air-assisted deformation. The diameter and height of nano-pillars, micro-lens and macrobase can be controlled precisely by fine-tuning the process parameters. The multifunctional properties of the BIC eye, such as superhydrophobicity, antireflection and other optical characteristics, are investigated. It is found that the micro-lens with nano-pillars can effectively improve the surface wettability with a contact angle (CA) of 152° and contact angle hysteresis of 12°, and enhance transmittance by 2% over the wavelength range of 200-1200 nm. Moreover, the final hierarchical compound eye exhibits the excellent imaging property and a wide field-of-view of 120° without distortion. These multifunctional properties will enable the widespread application of the compound eye in diverse real-time environmental conditions.