Synthetic aperture microscopy based on referenceless phase retrieval with an electrically tunable lens.

Area of Science:

• Optics and Photonics
• Microscopy Techniques
• Biomedical Imaging

Background:

• Phase imaging microscopy, including holography and phase retrieval, is gaining traction.
• Phase retrieval offers advantages like a reference-free setup, leading to more stable and compact systems.
• Traditional methods for synthetic aperture imaging often rely on bulky and expensive components.

Purpose of the Study:

• To present a novel optical setup for enhanced resolution phase imaging microscopy.
• To implement synthetic aperture imaging based on phase retrieval using an electrically tunable lens (ETL).
• To demonstrate the practical application of the developed technique for imaging microstructures and biological samples.

Main Methods:

• Developed a phase retrieval-based optical setup incorporating an electrically tunable lens (ETL) for synthetic aperture imaging.
• Implemented a general calibration algorithm for image registration, magnification correction, and axial plane determination prior to phase retrieval.
• Utilized the ETL as a compact and cost-effective alternative to translation stages and spatial light modulators.

Main Results:

• Achieved resolution-enhanced phase imaging of a phase grating.
• Successfully obtained high-resolution images of biological cells.
• Demonstrated the practical utility and effectiveness of the ETL-based synthetic aperture phase retrieval technique.

Conclusions:

• The proposed method effectively enhances image resolution in phase imaging microscopy.
• Electrically tunable lenses provide a practical and economical solution for advanced microscopy setups.
• This technique holds promise for improved imaging of microscopic structures and biological specimens.