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Published on: January 28, 2019
Wave-aberration control with a liquid crystal on silicon (LCOS) spatial phase modulator
Enrique J Fernández1, Pedro M Prieto, Pablo Artal
1Centro de Investigación en Optica y Nanofísica, Universidad de Murcia, Campus de Espinardo, Murcia, Spain. enriquej@um.es
Optics Express
|June 25, 2009
Summary
Liquid crystal on Silicon (LCOS) phase modulators excel in adaptive optics. We determined their usable limits by analyzing Zernike polynomial generation, minimizing diffraction artifacts for better visual simulation and ophthalmic testing.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Liquid Crystal on Silicon (LCOS) spatial phase modulators offer high-speed, high-fidelity adaptive optics.
- Unlike deformable mirrors, LCOS devices can generate discontinuous phase profiles and utilize phase wrapping to increase effective stroke.
Purpose of the Study:
- To characterize the performance limits of LCOS phase modulators.
- To determine the usable ranges for generating Zernike polynomials without significant diffraction artifacts.
Main Methods:
- Systematically degraded images using LCOS-generated Zernike polynomials.
- Compared recorded images with theoretical digital counterparts.
- Analyzed image quality degradation as a function of Zernike coefficient values.
Main Results:
- Image degradation reached a limit for specific Zernike coefficient values, with further increases having no additional effect.
- This limit is attributed to intensified 0-order diffraction.
- Usable operational limits of the LCOS phase modulator, free from diffraction artifacts, were determined.
Conclusions:
- The study establishes practical operational boundaries for LCOS phase modulators in adaptive optics.
- Findings are crucial for visual simulation and ophthalmic testing applications.
- Results are relevant for all adaptive optics systems employing liquid crystal-based devices.
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