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Optimum phase for rugate filter synthesis by Fourier transforms.
1Institute for Microstructural Sciences, National Research Council of Canada, Ottawa, Ontario, Canada. Pierre.Verly@nrc-cnrc.gc.ca
Applied Optics
|April 5, 2011
Summary
This study introduces an optimized phase development method for synthesizing rugate reflectors using Fourier transforms. Phase shaping alone yields effective rugate filter designs with unique advantages.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Rugate reflectors are optical filters with periodic refractive index variations.
- Designing rugate reflectors typically involves optimizing both magnitude and phase of the refractive index profile.
- The phase component of the refractive index profile is often considered a secondary parameter compared to the magnitude.
Purpose of the Study:
- To develop an optimized phase for synthesizing rugate reflectors.
- To investigate the efficacy of phase shaping alone in rugate filter design.
- To explore the advantages and unique operating mode of phase-driven design.
Main Methods:
- Utilizing a simple Fourier transform for phase development.
- Focusing solely on phase shaping as the primary design parameter.
- Analyzing the spectral characteristics resulting from phase manipulation.
Main Results:
- An optimum phase function was successfully developed for rugate reflector synthesis.
- Phase shaping alone demonstrated surprisingly effective results in rugate filter design.
- The phase-shaping approach offers additional advantages in rugate filter synthesis.
Conclusions:
- Optimized phase development is a viable and effective strategy for rugate reflector synthesis.
- Phase shaping alone can produce high-quality rugate filters, challenging traditional design approaches.
- The presented design procedure offers a novel and interesting method for optical filter fabrication.
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