Digital self-referencing quantitative phase microscopy by wavefront folding in holographic image reconstruction

Area of Science:

• Optics and Photonics
• Biomedical Engineering
• Microscopy

Background:

• Quantitative phase microscopy (QPM) is crucial for label-free imaging of biological samples.
• Digital holographic microscopy (DHM) offers high-resolution imaging but often requires complex phase retrieval.
• Microfluidic devices present unique challenges for accurate phase measurements due to complex geometries.

Discussion:

• Digital self-referencing holography (DSRH) is introduced as a fully numerical method for QPM in microfluidics.
• The technique manipulates the retrieved complex wavefront through image plane folding for self-referencing.
• Phase map correction is achieved by subtracting a background area outside the microfluidic channel.

Key Insights:

• DSRH simplifies the quantitative phase microscopy process for microfluidic applications.
• The numerical folding operation effectively retrieves accurate phase maps from complex wavefronts.
• Demonstrated successful retrieval of quantitative phase maps for bovine spermatozoa and in vitro cells.

Outlook:

• Potential for broader adoption of QPM in microfluidic cell analysis and diagnostics.
• Further optimization of DSRH for high-throughput screening and dynamic biological processes.
• Integration of DSRH with other advanced imaging modalities for multi-modal analysis.