Bañas, Andrew Rafael1; Kopylov, Oleksii1; Villangca, Mark Jayson1; Palima, Darwin1; Glückstad, Jesper1
1 Department of Photonics Engineering, Technical University of Denmark2 Programmable Phase Optics, Department of Photonics Engineering, Technical University of Denmark
Generalized Phase Contrast (GPC) is an efficient method for generating speckle-free contiguous optical distributions useful in diverse applications such as static beam shaping, optical manipulation and, recently, for excitation in two-photon optogenetics. GPC allows efficient utilization of typical Gaussian lasers in such applications using binary-only phase modulation. In this work, we experimentally verify previously derived conditions for photon-efficient light shaping with GPC [Opt. Express 22(5), 5299 (2014)]. We demonstrate a compact implementation of GPC for creating practical illumination shapes that can find use in lightefficient industrial or commercial applications. Using a dynamic spatial light modulator, we also show simple and efficient beam shaping of reconfigurable shapes geared towards materials processing, biophotonics research and other contemporary applications. Our experiments give ~80% efficiency, ~3x intensity gain, and ~90% energy savings which are in good agreement with previous theoretical estimations.
Optics Express, 2014, Vol 22, Issue 20, p. 23759-23769