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Compensation of coherence effects in an optical spectrum analyzer
Applied Optics
|March 25, 2010
Summary
This study presents an optical technique to correct for imperfect illumination in Mach-Zehnder spectrum analyzers. It enables real-time spectral analysis by automatically determining amplitude and phase.
Area of Science:
- Optics and Photonics
- Interferometry
- Optical Metrology
Background:
- Mach-Zehnder interferometers are crucial for spectral analysis.
- Imperfect spatial coherent illumination degrades analyzer performance.
- Accurate spectral amplitude and phase determination is vital for optical measurements.
Purpose of the Study:
- To introduce an optical technique for compensating imperfect spatial coherent illumination.
- To describe methods for experimentally determining the complex mutual coherence function.
- To enable real-time spectral amplitude and phase measurement.
Main Methods:
- Utilizing a modified Mach-Zehnder spectrum analyzer.
- Developing experimental methods to measure the complex mutual coherence function.
- Incorporating a computer-controlled calibrated phase shifter.
Main Results:
- The proposed technique effectively compensates for illumination imperfections.
- Experimental methods accurately determine the complex mutual coherence function.
- Real-time spectral amplitude and phase determination is achieved.
Conclusions:
- The developed optical technique enhances Mach-Zehnder spectrum analyzer performance.
- Accurate characterization of illumination coherence is now feasible.
- Automated real-time spectral analysis is enabled for advanced optical applications.
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