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Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
Published on: January 28, 2019
Generation of multiple vortex-cones by direct-phase modulation of annular aperture array.
Seong-Woo Cho1, Hwi Kim, Joonku Hahn
1National Creative Research Center for Active Plasmonics Application Systems and School of Electrical Engineering, Seoul National University, Seoul, South Korea.
Applied Optics
|October 24, 2012
Summary
Researchers generated multiple vortex cones using a spatial light modulator (SLM) and an annular aperture array. This method allows simultaneous control over topological charge and horizontal positions of these light structures.
Area of Science:
- Optics and Photonics
- Laser Physics
- Nanophotonics
Background:
- Vortex beams, characterized by a helical phase front, are crucial in optical manipulation and communication.
- Generating and controlling multiple vortex beams with precise spatial positioning presents a significant challenge.
Purpose of the Study:
- To investigate the generation of multiple vortex cones using an annular aperture array.
- To explore the capability of direct-phase modulation for controlling vortex cone properties.
Main Methods:
- Utilizing a spatial light modulator (SLM) for direct-phase modulation of an annular aperture.
- Employing an annular aperture array to create multiple beamlets.
- Implementing downscale imaging techniques to project the SLM pattern onto the aperture surface.
Main Results:
- Successfully generated multiple vortex cones.
- Demonstrated simultaneous control over the topological charge of the vortex cones.
- Achieved precise control over the horizontal positions of the multiple vortex cones.
Conclusions:
- Direct-phase modulation of an annular aperture array is an effective method for generating and controlling multiple vortex cones.
- This technique offers simultaneous manipulation of topological charge and spatial positioning, opening new avenues for optical applications.
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