Single-exposure optical focusing inside scattering media using binarized time-reversed adapted perturbation

Area of Science:

• Biomedical Optics
• Biophysics
• Optical Engineering

Background:

• Light scattering in biological tissues impedes deep-focusing for optical imaging, manipulation, and therapy.
• Existing wavefront shaping techniques struggle to meet the high gain, speed, and contrast requirements for in vivo applications.

Purpose of the Study:

• To develop a novel technique for achieving high-resolution optical focusing deep within scattering biological tissues.
• To overcome the limitations of current methods in speed, gain, and focal contrast for in vivo optical applications.

Main Methods:

• Rapidly measuring the perturbed optical field within a single camera exposure.
• Adaptively time-reversing the phase-binarized perturbation to synthesize a phase-conjugated wavefront.
• Achieving wavefront conjugation within milliseconds, significantly faster than previous digital methods.

Main Results:

• Demonstrated real-time optical focusing in dynamic scattering media.
• Extended the depth penetration of laser speckle contrast imaging.
• Achieved a millisecond response time for wavefront synthesis, two orders of magnitude faster than prior records.

Conclusions:

• The developed technique offers an unprecedented combination of fast response, high gain, and high focusing contrast.
• This advancement represents a significant step towards practical in vivo deep tissue optical imaging, manipulation, and therapy.