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Synthesis of high rejection filters with the Fourier transform method
Applied Optics
|June 18, 2010
Summary
This study modifies the Fourier transform method for high-rejection filter synthesis, achieving low minimum transmittances. A faster empirical optimization procedure is also presented for spectral performance tuning.
Area of Science:
- Optical Engineering
- Materials Science
Background:
- The Fourier transform method is theoretically limited to small rejection ratios in filter synthesis.
- Practical applications require filters with high rejection and low minimum transmittance.
Purpose of the Study:
- To adapt the Fourier transform method for synthesizing high-rejection optical filters.
- To introduce a faster optimization technique for spectral performance.
Main Methods:
- Modified Fourier transform method utilizing two new spectral functions.
- An empirical procedure for rapid optimization of spectral performance.
- Numerical illustration with various spectral shapes.
Main Results:
- Successful synthesis of high-rejection filters with minimum transmittances as low as 10(-4).
- Demonstration of a significantly faster empirical optimization compared to traditional refinement methods.
- Validation of the proposed method across diverse spectral shapes.
Conclusions:
- The modified Fourier transform method enables practical synthesis of advanced optical filters.
- The empirical optimization offers an efficient alternative for improving filter spectral performance.
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