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Updated: Aug 11, 2026
15:25
Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters
Published on: February 4, 2018
Polarization-independent and tunable comb filter based on a free-space coupling technique
Haifeng Lu1, Zhuangqi Cao, Honggen Li
1Department of Physics, Shanghai Jiao Tong University, China. sealu@sjtu.edu.cn
Optics Letters
|February 17, 2006
Summary
A novel tunable comb filter, independent of polarization, was demonstrated using a simple glass slab and gold films. This device offers high channel isolation and low insertion loss for optical applications.
Area of Science:
- Photonics
- Optical Engineering
- Materials Science
Background:
- Comb filters are crucial optical components for wavelength division multiplexing.
- Existing filters often suffer from polarization dependence or complex fabrication.
- Need for compact, tunable, and polarization-independent optical filters.
Purpose of the Study:
- To demonstrate a novel, polarization-independent, and tunable comb filter.
- To characterize the filter's performance in terms of channel isolation, insertion loss, and channel spacing.
- To present a simple and potentially cost-effective filter design.
Main Methods:
- Fabrication of a filter comprising a single glass slab between two gold films.
- Experimental demonstration of the filter's operation.
- Measurement of key performance metrics including channel isolation, insertion loss, and channel spacing.
Main Results:
- The demonstrated filter is polarization-independent.
- Achieved channel isolation greater than 12 dB.
- Observed insertion loss less than 0.2 dB.
- Accurate channel spacing of 0.8 nm achieved.
- The filter is tunable.
Conclusions:
- A novel, simple, and effective polarization-independent tunable comb filter has been successfully demonstrated.
- The filter's performance metrics meet requirements for various optical communication and signal processing applications.
- The proposed design offers a promising alternative to existing complex filter technologies.
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