Non-invasive and noise-robust light focusing using confocal wavefront shaping

Area of Science:

• Biomedical Optics
• Neuroimaging
• Fluorescence Microscopy

Background:

• Wavefront shaping enables deep tissue imaging by correcting optical aberrations.
• Existing methods struggle with weak fluorescent signals from biological samples like neurons.
• Manual feedback from fluorescent beads is not generalizable to biological imaging.

Purpose of the Study:

• To develop a wavefront shaping approach for imaging weak fluorescent signals from neurons deep within scattering tissue.
• To improve the signal-to-noise ratio for deep tissue fluorescence imaging.
• To overcome limitations of previous wavefront shaping techniques that require strong feedback signals.

Main Methods:

• A confocal modulation of both illumination and imaging arms was employed.
• Aberrations were corrected optically before reaching the detector.
• A mathematically derived score function was used for modulation evaluation.

Main Results:

• The developed technique successfully imaged fluorescence neurons through thick scattering tissue.
• The method effectively directed the low photon budget into a single sensor spot.
• High signal-to-noise ratio detection was achieved despite weak neuronal fluorescence.

Conclusions:

• The proposed confocal wavefront shaping approach is effective for imaging faint fluorescent targets in scattering media.
• This technique overcomes the limitations of previous methods for imaging biological samples.
• It offers a promising solution for deep tissue neuroimaging applications.