Open AccessBeam shaping with tip-tilt varifocal mirror for indoor optical wireless communication
Author(s) -
Corey Pollock,
Jessica Morrison,
Matthias Imboden,
Thomas D. C. Little,
David J. Bishop
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.020274
Subject(s) - optics , tilt (camera) , deformable mirror , microelectromechanical systems , optical communication , beam (structure) , optical wireless , materials science , free space optical communication , light beam , curvature , beam divergence , optical fiber , wireless , adaptive optics , physics , computer science , optoelectronics , laser beam quality , telecommunications , engineering , laser beams , laser , mechanical engineering , geometry , mathematics
MEMS mirrors are currently used in many applications to steer beams of light. An area of continued research is developing mirrors with varifocal capability that allows the beam to be shaped and focused. In this work, we study the varifocal capability of a 380 μm diameter, thermally actuated MEMS mirror with a ± 40° tip-tilt angle and a radius of curvature between -0.48 mm to 20.5 mm. Light is coupled to the mirror via a single mode optical fiber, similar to an indoor optical wireless communication architecture. The performance of the mirror is characterized with respect to (1) the profile of the reflected beam as the mirror deforms and (2) the mirror's impact when integrated into an optical communication system. We found that the mirror can focus light to a beam with a 0.18° half-angle divergence. Additionally, the ability to change the shape of fiberized light from a wide to narrow beam provides an unmatched level of dynamic control and significantly improves the bit error rate in an optical communication system.