Publications
Munkyu Kang; Elizabeth Murray; Leyla A. Kabuli; Rikky Muller; Laura Waller
Correcting curvature in micromirror-based spatial light modulators with a microlens array Journal Article
In: Opt. Express, vol. 34, no. 8, pp. 15783–15794, 2026.
Abstract | Links | BibTeX | Tags: Deformable mirrors; Diffraction efficiency; Holographic displays; Microlens arrays; Phase modulation; Spatial light modulators
@article{Kang:26,
title = {Correcting curvature in micromirror-based spatial light modulators with a microlens array},
author = {Munkyu Kang and Elizabeth Murray and Leyla A. Kabuli and Rikky Muller and Laura Waller},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-34-8-15783},
doi = {10.1364/OE.593116},
year = {2026},
date = {2026-04-01},
journal = {Opt. Express},
volume = {34},
number = {8},
pages = {15783–15794},
publisher = {Optica Publishing Group},
abstract = {Computer-generated holography requires high-speed spatial light modulators (SLMs) for dynamically patterning light in 3D. Piston-motion micromirror-based SLMs support high-speed ($geq$ 10 kHz) phase modulation; however, fabricating micromirror arrays with sufficient fill factor necessary for high diffraction efficiency is challenging. In particular, the larger mirrors of high fill factor designs are susceptible to stress-induced curvature that significantly degrades optical performance. In this work, we introduce an optical compensation method using a pitch-matched microlens array (MLA) to focus light onto just the center of each mirror. Our approach thus avoids curvature-induced artifacts and improves optical fill factor to nearly 100%, independent of the original mechanical fill factor. Through simulations and experiments on a fabricated micromirror array with bowed mirrors, we show that the Pearson correlation coefficient of the imparted phase profile is improved from 0.11 to 0.85 and the brightness of a holographically-generated single spot is enhanced by 8× with our microlens array in place. Our hybrid optical-electromechanical strategy thus provides a scalable path toward high-speed, high-fidelity wavefront control for applications such as adaptive optics, holographic displays, and optogenetics.},
keywords = {Deformable mirrors; Diffraction efficiency; Holographic displays; Microlens arrays; Phase modulation; Spatial light modulators},
pubstate = {published},
tppubtype = {article}
}
Computer-generated holography requires high-speed spatial light modulators (SLMs) for dynamically patterning light in 3D. Piston-motion micromirror-based SLMs support high-speed ($geq$ 10 kHz) phase modulation; however, fabricating micromirror arrays with sufficient fill factor necessary for high diffraction efficiency is challenging. In particular, the larger mirrors of high fill factor designs are susceptible to stress-induced curvature that significantly degrades optical performance. In this work, we introduce an optical compensation method using a pitch-matched microlens array (MLA) to focus light onto just the center of each mirror. Our approach thus avoids curvature-induced artifacts and improves optical fill factor to nearly 100%, independent of the original mechanical fill factor. Through simulations and experiments on a fabricated micromirror array with bowed mirrors, we show that the Pearson correlation coefficient of the imparted phase profile is improved from 0.11 to 0.85 and the brightness of a holographically-generated single spot is enhanced by 8× with our microlens array in place. Our hybrid optical-electromechanical strategy thus provides a scalable path toward high-speed, high-fidelity wavefront control for applications such as adaptive optics, holographic displays, and optogenetics.