One-shot phase-recovery using a cellphone RGB camera on a Jamin-Lebedeff microscope

Area of Science:

• Biophysics
• Optical Microscopy
• Image Processing

Background:

• Jamin-Lebedeff (JL) polarization interference microscopy is a classical technique for measuring optical path differences (OPD) in transparent samples.
• Traditional JL microscopy uses a Michel-Levy chart for OPD deduction, limiting real-time analysis.
• Quantitative phase measurements are crucial in cytology for determining dry mass per area of cells.

Purpose of the Study:

• To develop a real-time quantitative phase measurement method using Jamin-Lebedeff microscopy.
• To modernize the JL setup with 3D-printed parts and a cellphone for enhanced functionality.
• To enable accurate OPD determination in biological samples, including living cells.

Main Methods:

• Implemented a single-shot phase retrieval algorithm for real-time measurements.
• Integrated 3D-printed components and a cellphone RGB-camera into the JL microscope setup.
• Developed a gradient-descent based inverse problem with total-variation regularization for accurate phase mapping and unwrapping.

Main Results:

• Successfully adapted a classical Jamin-Lebedeff microscope for real-time quantitative phase measurements.
• Demonstrated the method's efficacy on fixed and living biological samples, as well as reference objects.
• Achieved accurate optical path difference (OPD) mapping, correlating with dry mass per area in cells.

Conclusions:

• The modernized JL microscopy enables rapid, quantitative phase imaging of transparent samples.
• The developed phase retrieval algorithm overcomes limitations of traditional methods, allowing real-time analysis.
• This approach provides a cost-effective and accessible tool for quantitative phase imaging in various biological applications.