Quantitative DIC microscopy using an off-axis self-interference approach.

Area of Science:

• Biomedical Optics
• Microscopy Techniques
• Quantitative Imaging

Background:

• Traditional Normarski differential interference contrast (DIC) microscopy excels at imaging unstained biological samples.
• A key limitation of conventional DIC microscopy is its inability to provide quantitative measurements.
• There is a need for quantitative imaging methods compatible with standard microscopy setups.

Purpose of the Study:

• To develop a quantitative DIC microscopy method.
• To overcome the nonquantitative nature of traditional DIC imaging.
• To enable precise phase measurements in biological samples.

Main Methods:

• Developed a quantitative DIC microscopy approach utilizing off-axis sample self-interference.
• Applied digital holography algorithms to extract quantitative phase gradients in orthogonal directions.
• Employed spiral integration of phase gradients to reconstruct a quantitative phase image.
• Demonstrated compatibility with standard microscopes and optical sectioning via enlarged illumination numerical aperture (NA).

Main Results:

• Successfully achieved quantitative phase imaging using a modified DIC setup.
• The method provides accurate phase gradient measurements.
• The technique is easily implementable on existing microscopy hardware.
• Optical sectioning capabilities were maintained and enhanced.

Conclusions:

• The developed quantitative DIC microscopy method effectively addresses the limitations of traditional approaches.
• This technique offers a practical and accessible way to obtain quantitative phase information from biological samples.
• The method holds potential for advancing quantitative imaging in various biological research fields.