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Updated: Feb 14, 2026
09:33
Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
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MEMS-tunable dielectric metasurface lens.
Ehsan Arbabi1, Amir Arbabi1,2, Seyedeh Mahsa Kamali1
1T. J. Watson Laboratory of Applied Physics, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA, 91125, USA.
Nature Communications
|February 25, 2018
Summary
Researchers developed tunable metasurface lenses using microelectromechanical systems (MEMS). These compact, fast optical devices offer significant power changes for advanced imaging and beam scanning applications.
Area of Science:
- Optics and Photonics
- Materials Science
- Microelectromechanical Systems
Background:
- Conventional varifocal lenses are bulky and slow due to multiple refractive elements.
- Metasurfaces offer a path to thin, lightweight optical elements with engineered phase profiles.
Purpose of the Study:
- To demonstrate tunable metasurface doublets using microelectromechanical systems (MEMS).
- To explore their potential for compact, fast, and reconfigurable optical systems.
Main Methods:
- Fabrication of tunable metasurface doublets using lithographic techniques.
- Integration with microelectromechanical systems (MEMS) for tunable optical power.
- Assembly into compact microscope systems for 3D imaging.
Main Results:
- Achieved over 60 diopters of optical power change with a 1-μm metasurface movement.
- Demonstrated potential scanning frequencies up to a few kHz.
- Developed compact (~1 mm thick) microscopes with large corrected fields of view (~40 degrees) and fast axial scanning.
Conclusions:
- MEMS-integrated metasurfaces represent a promising platform for tunable and reconfigurable optics.
- This technology enables miniaturized, high-performance imaging and beam scanning devices.
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