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Real-time optical signal processors employing optical feedback: amplitude and phase control
Applied Optics
|February 19, 2010
Summary
Optical feedback techniques enable independent amplitude and phase control in optical signal processing. Phase-only filters offer greater flexibility compared to combined phase-amplitude filters in real-time systems.
Area of Science:
- Optics
- Optical Computing
- Signal Processing
Background:
- Real-time coherent optical signal processors are gaining traction.
- A key limitation is the phase-only nature of optical processing materials.
- This restricts spatial filters to phase-only or amplitude-only types.
Purpose of the Study:
- To investigate optical feedback techniques for simultaneous amplitude and phase control.
- To assess the flexibility of phase-only filters within feedback systems.
Main Methods:
- Application of optical feedback techniques.
- Synthesis of spatial filters using phase-only materials.
- Comparison of different feedback system configurations (phase-only vs. combined phase-amplitude).
Main Results:
- Optical feedback successfully achieves independent amplitude and phase control with phase-only filters.
- The phase-only filter feedback system demonstrates superior flexibility.
- Performance is compared against systems using combined phase-only and amplitude-only filters.
Conclusions:
- Optical feedback is a viable method for advanced control in optical signal processing.
- Phase-only filters, when integrated with optical feedback, provide a highly flexible solution.
- This approach overcomes limitations of traditional phase-only or amplitude-only filters in real-time optical computing.
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