Generation of Diffraction-Free Optical Beams Using Wrinkled Membranes

TL;DR

This paper demonstrates a novel, low-cost, flexible optical device using wrinkled membranes that can generate diffraction-free focused beams with potential for miniaturized optical systems.

Contribution

Introduction of a new wrinkle-based optical focusing device that converts collimated light into diffraction-free beams, with theoretical and experimental validation.

Findings

Beam diameters of 300-400 μm observed in experiments.

Predicted focal spot size as small as 50 μm if fabrication issues are addressed.

Device is low cost, lightweight, and flexible.

Abstract

We report the first demonstration of wrinkled membranes as a kind of optical focusing devices, which are low cost, light weight and flexible. Our device consists of concentric wrinkle rings on a gold-PDMS bilayer membrane, which converts collimated illuminations to diffraction-free focused beams. Beam diameters of 300-400 {\mu}m have been observed in the visible range. By comparing the theoretically calculated and experimentally measured focal spot profiles, we predict a focal spot size as small as around 50 {\mu}m if fabrication eccentricity can be eliminated.