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Updated: Oct 28, 2025
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
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Genetic-algorithm-assisted coherent enhancement absorption in scattering media by exploiting transmission and
Optics Express
|July 16, 2021
Summary
Coherent enhancement absorption (CEA) uses a genetic algorithm to focus light within scattering media for improved deep-tissue imaging. This method delivers over half the incident light to a 5-μm absorber, enhancing absorption fourfold compared to random input.
Area of Science:
- Biophotonics
- Optical Imaging
- Wavefront Shaping
Background:
- Coherent enhancement absorption (CEA) is crucial for deep-tissue optical imaging.
- CEA improves signal strength and resolution by delivering light to targeted locations.
- Scattering media pose challenges for light delivery in biological tissues.
Purpose of the Study:
- To develop a numerical framework for studying CEA in scattering media with local absorption.
- To optimize light delivery to absorbers within scattering media using a genetic algorithm.
- To quantify the effectiveness of CEA for targeted light delivery.
Main Methods:
- Finite-difference time-domain (FDTD) numerical framework.
- Construction of transmission and reflection matrices for scattering media with open boundaries.
- Genetic-algorithm-assisted model to minimize total transmittance and reflectance simultaneously.
Main Results:
- Demonstrated CEA for scattering media with local absorption by modulating incident wavefronts.
- Successfully delivered over 50% of incident light to a 5-μm absorber within a 15 μm × 12 μm scattering medium.
- Achieved more than fourfold enhancement in absorption compared to random input, with potential for higher enhancement in smaller absorbers.
Conclusions:
- The developed genetic-algorithm-assisted model effectively realizes CEA for targeted light delivery in scattering media.
- The method's effectiveness is inversely proportional to the scattering medium's openness.
- This technique holds promise for applications in targeted light delivery and deep-tissue optical imaging.
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