title: LCoS nematic SLM characterization and modeling for diffraction efficiency optimization, zero and ghost orders suppression.
abstract: Pixilated spatial light modulators are efficient devices to shape the wavefront of a laser beam or to perform Fourier optical filtering. When conjugated with the back focal plane of a microscope objective, they allow an efficient redistribution of laser light energy. These intensity patterns are usually polluted by undesired spots so-called ghosts and zero-orders whose intensities depend on displayed patterns. In this work, we propose a model to account for these discrepancies and demonstrate the possibility to efficiently reduce the intensity of the zero-order up to 95%, the intensity of the ghost up to 96% and increase diffraction efficiency up to 44%. Our model suggests physical cross-talk between pixels and thus, filtering of addressed high spatial frequencies. The method implementation relies on simple preliminary characterization of the SLM and can be computed a priori with any phase profile. The performance of this method is demonstrated employing a Hamamatsu LCoS SLM X10468-02 with two-photon excitation of fluorescent Rhodamine layers.
authors.affiliation: Laboratory of Neurophysiology and New Microscopies, Wavefront Engineering group (INSERM S603, CNRS UMR 8154), Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saints Pères, 75006 Paris, France.
authors.forename: Emiliano
authors.initials: E
authors.lastname: Ronzitti
authors.forename: Marc
authors.initials: M
authors.lastname: Guillon
authors.forename: Vincent
authors.initials: V
authors.lastname: de Sars
authors.forename: Valentina
authors.initials: V
authors.lastname: Emiliani
mesh_terms: D005453:Fluorescence; D021621:Imaging, Three-Dimensional; D007909:Lenses; D008027:Light; D050866:Liquid Crystals / Q000737:chemistry*; D009474:Neurons / Q000166:cytology; D055095:Optics and Photonics; D012825:Silicon / Q000737:chemistry*
chemical_list: D012825:Silicon