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Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters
Published on: February 4, 2018
Low-loss all-fiber acousto-optic tunable filter.
Optics Letters
|January 15, 1997
Summary
Researchers developed simple all-fiber, tunable acousto-optic spectral filters using null couplers. Improved uniformity and a double-pass design significantly enhanced filter performance, reducing bandwidth and suppressing sidelobes.
Area of Science:
- Photonics and Optical Engineering
- Fiber Optics
- Acousto-Optic Devices
Background:
- Acousto-optic spectral filters are crucial for wavelength selection in optical systems.
- Null couplers offer a promising platform for developing compact and efficient fiber-based filters.
- Achieving high performance requires precise control over coupler fabrication and uniformity.
Purpose of the Study:
- To report advances in simple all-fiber, tunable acousto-optic spectral filters.
- To investigate the impact of coupler uniformity on filter performance.
- To explore the benefits of a double-pass arrangement for filter bandwidth and frequency shift.
Main Methods:
- Development of all-fiber acousto-optic spectral filters utilizing null couplers.
- Fabrication of null couplers with improved uniformity control.
- Implementation of a double-pass configuration for filter characterization.
Main Results:
- The developed filters exhibit performance aligning with theoretical predictions.
- Improved coupler uniformity is key to achieving high-performance filters.
- The double-pass arrangement achieved -20 dB sidelobe suppression and reduced filter bandwidth.
- The double-pass configuration doubled the obtainable frequency shifts.
Conclusions:
- Simple all-fiber, tunable acousto-optic spectral filters based on null couplers represent a significant advancement.
- Precise control over coupler uniformity is essential for optimal filter performance.
- The double-pass configuration offers a practical method for enhancing filter characteristics and operational range.
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