Quantitative phase-gradient imaging at high resolution with asymmetric illumination-based differential phase contrast

Area of Science:

• Optical imaging
• Microscopy techniques
• Biophysics

Background:

• Quantitative phase imaging is crucial for analyzing transparent specimens.
• Existing methods like differential interference contrast (DIC) have limitations, including the need for phase shifting and artifacts with birefringent samples.

Purpose of the Study:

• To introduce and characterize a novel full-field phase-gradient imaging method: asymmetric illumination-based differential phase contrast (AIDPC).
• To evaluate AIDPC's performance and compare it with existing techniques for enhanced microscopy applications.

Main Methods:

• Developed asymmetric illumination-based differential phase contrast (AIDPC) for full-field phase-gradient imaging.
• Utilized the phase-gradient transfer-function approach for imaging property evaluation.
• Experimentally imaged an optical fiber and a skeletal muscle section.

Main Results:

• AIDPC enables quantitative phase gradient imaging without requiring phase shifting.
• The method produces artifact-free images, particularly for birefringent specimens.
• AIDPC offers advantages over DIC, including shorter camera exposure and larger depth of focus.

Conclusions:

• AIDPC is a robust and versatile phase-gradient imaging technique.
• Its capabilities extend to transfer-function engineering, simultaneous fluorescence imaging, and automated live cell imaging.
• AIDPC presents a significant advancement for high-resolution, quantitative microscopy.