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Topological spatial differentiation via complex amplitude filtering in Fourier space
Optics Letters
|June 30, 2023
Summary
We developed a novel topological optical differentiation method using complex amplitude filtering. This technique enables precise edge detection in images, paving the way for compact optical processing systems.
Area of Science:
- Photonics
- Optical Engineering
- Image Processing
Background:
- Optical analog differentiation is crucial for edge-based image processing.
- Existing methods have limitations in precision and compactness.
Purpose of the Study:
- To introduce a topological optical differentiation scheme.
- To demonstrate its capabilities in isotropic and anisotropic differentiation and multiline edge detection.
Main Methods:
- Utilizing complex amplitude filtering, including amplitude and spiral phase modulation in Fourier space.
- Theoretical and experimental validation of the differentiation operations.
Main Results:
- Demonstrated isotropic and anisotropic multiple-order optical differentiation.
- Achieved multiline edge detection for amplitude and phase objects based on differential order.
Conclusions:
- The proposed topological optical differentiation scheme offers a new approach for nanophotonic differentiators.
- This work advances the development of compact and efficient optical image-processing systems.
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