Contribution to the Improvement of the Correlation Filter Method for Modal Analysis with a Spatial Light Modulator

Area of Science:

• Optics and Photonics
• Waveguide Theory
• Computational Physics

Background:

• Modal decomposition is crucial for understanding light propagation in waveguides and photonic devices.
• Computer-generated holograms (CGHs) acting as match filters in spatial light modulators (SLMs) offer a method for modal analysis.

Purpose of the Study:

• To present optimized operational procedures for CGH-based modal decomposition.
• To enhance the accuracy and robustness of modal analysis in optical systems.

Main Methods:

• Developing a filter size adjustment method based on standard fiber LP-mode symmetry.
• Investigating the impact of mode normalization on noise in complex amplitude encoding.
• Proposing a robust technique for measuring the phase difference between optical modes.

Main Results:

• Demonstrated effective filter size adjustment for improved modal decomposition.
• Quantified the influence of mode normalization on encoding-inherent noise.
• Successfully tested wavefront reconstruction in a few-mode fiber using the proposed procedures.

Conclusions:

• The presented procedures offer practical guidelines for maximizing the effectiveness of CGH-based modal decomposition.
• The study provides a robust framework for accurate modal analysis and phase difference measurement in optical fibers.