Polarization-independent differential interference contrast and off-axis holography combined module

Area of Science:

• Optics and Photonics
• Biomedical Imaging
• Microscopy Technology

Background:

• Traditional microscopy techniques often require sample labeling or specialized equipment.
• Differential Interference Contrast (DIC) and Digital Holographic Microscopy (DHM) offer advanced imaging capabilities but typically require dedicated setups.
• Integrating multiple advanced microscopy modalities into a single, adaptable system is a significant challenge.

Purpose of the Study:

• To develop an external, portable module that enhances existing bright-field microscopes.
• To enable both Differential Interference Contrast (DIC) and Digital Holographic Microscopy (DHM) imaging capabilities.
• To provide label-free imaging of biological samples using a versatile and accessible module.

Main Methods:

• An external module with simple optical elements was designed for integration between the microscope output and camera.
• The module facilitates polarization DIC imaging without specialized polarization components, usable with white-light or coherent illumination.
• Rotating an element within the module generates off-axis holograms for quantitative phase reconstruction under coherent illumination.

Main Results:

• The module successfully transforms bright-field microscopy into DIC and DHM.
• Label-free imaging of biological samples was achieved using the DIC mode.
• Quantitative phase imaging was demonstrated through holographic reconstruction of the same samples.
• The system was validated using silica microspheres and biological cells.

Conclusions:

• The developed external module offers a cost-effective and versatile solution for advanced microscopy.
• It enables simultaneous label-free DIC and quantitative phase imaging with existing microscopes.
• This technology has potential applications in various fields requiring high-resolution biological sample analysis.