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Updated: Jun 22, 2026
07:34
Excitation-Scanning Hyperspectral Imaging Microscopy to Efficiently Discriminate Fluorescence Signals
Published on: August 22, 2019
Selective excitation between two-photon and three-photon fluorescence with engineered cost functions
Optics Express
|June 2, 2009
Summary
Coherent control optimized two-photon (2P) and three-photon (3P) fluorescence. Modifying the self-learning algorithm
Area of Science:
- Biophotonics
- Laser Physics
- Spectroscopy
Background:
- Two-photon (2P) and three-photon (3P) fluorescence microscopy are valuable imaging techniques.
- L-Tryptophan and enhanced green fluorescence protein are important biological molecules.
- Coherent control offers potential for enhancing fluorescence signals.
Purpose of the Study:
- To enhance the ratio of 2P fluorescence to 3P fluorescence using coherent control.
- To optimize the trade-off between fluorescence ratio and 2P fluorescence intensity.
- To develop optimal pulse shapes for improved 2P fluorescence imaging.
Main Methods:
- Utilized a feedback-controlled self-learning loop for coherent control.
- Applied near-infrared femtosecond laser pulses to mixed biosamples (L-Tryptophan and EGFP).
- Engineered the cost function of the self-learning algorithm to balance fluorescence signals.
Main Results:
- Achieved enhancement of the 2P/3P fluorescence ratio.
- Observed a significant loss of 2P fluorescence accompanying ratio enhancement.
- Developed an engineered cost function to balance the 2P/3P ratio and 2P intensity.
Conclusions:
- Optimized pulse shapes can improve 2P fluorescence imaging.
- Reduced phototoxicity in 2P imaging is achievable.
- Coherent control with engineered cost functions offers a pathway for advanced bioimaging.
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