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Updated: Jun 10, 2026

Free-form Light Actuators — Fabrication and Control of Actuation in Microscopic Scale
Published on: May 25, 2016
Deformable curvature and beam scanning with an elastomeric concave grating actuated by a shape memory alloy
Raphael A Guerrero1, Michelle Wynne C Sze, Jose Ramon A Batiller
1Department of Physics, Ateneo de Manila University, Loyola Heights, Quezon City 1108, Philippines. rguerrero@admu.edu.ph
Abstract:
A concave diffraction grating with a tunable radius of curvature R is fabricated by embedding a nitinol wire within an elastomeric grating replica. Curvature of the grating is controlled via the shape memory effect, where strain in the wire is recovered due to martensite-austenite phase transformations induced by resistive heating. The generated force bends the grating into a variable curvature determined by applied current. The radius of curvature for the concave grating is variable from 170 to 44 mm over a current range of 0 to 2.5 A. Actuation of R redirects the grating normal, resulting in a scanning motion of the diffracted beam.
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