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Light-Driven Liquid Crystal Circular Dammann Grating Fabricated by a Micro-Patterned Liquid Crystal Polymer Phase
Xiaoqian Wang1, Saibo Wu2, Weiqiang Yang3
1Physics department, East China University of Science and Technology, Shanghai 200237, China. xqwang@ecust.edu.cn.
Polymers
|April 12, 2019
Summary
Researchers developed optically tunable circular Dammann gratings using liquid crystals. These gratings can generate uniform light patterns and offer flexible optical and electrical control for adaptive photonic chips.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Circular Dammann gratings are versatile diffractive optical elements.
- Electrically switchable gratings are well-researched, but optically tunable versions are less explored.
Purpose of the Study:
- To propose and demonstrate optically tunable circular Dammann gratings.
- To generate annular uniform-intensity patterns using liquid crystal gratings.
- To investigate maskless optical tuning methods.
Main Methods:
- Fabrication of three-order and eight-order binary-phase liquid crystal circular Dammann gratings using a micro-patterned liquid crystal polymer phase mask.
- Implementing two mutually orthogonal photo-induced alignments in adjacent domains.
- Demonstrating maskless optical tuning via ultraviolet light polarization and energy dose control.
Main Results:
- Generation of annular uniform-intensity patterns in the far field.
- Achieved high efficiencies and desirable uniformities in the gratings.
- Demonstrated outstanding optical and electrical tunabilities.
Conclusions:
- The proposed liquid crystal circular Dammann gratings offer significant optical and electrical tunability.
- These gratings have potential applications in adaptive photonic chips.
- Flexible stimulation by light or a combination of light and electric fields is enabled.
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