Compact lensless phase imager

Area of Science:

• Optical Imaging
• Biomedical Optics
• Microscopy

Background:

• Lensless quantitative phase imaging (QPI) offers high-contrast observation of biological samples over large fields of view (FOV).
• Existing QPI systems often involve complex, bulky illumination setups that obstruct sample access and limit practical application.
• The inherent simplicity of lensless QPI is hindered by challenges in illumination system design, particularly for achieving super-resolution or varied illumination angles.

Purpose of the Study:

• To propose and demonstrate a novel, compact side illumination system for lensless QPI.
• To overcome the limitations of conventional illumination methods by reducing system height and providing an unobstructed view.
• To enable high-contrast imaging of biological samples with a large FOV using a simplified optical setup.

Main Methods:

• Development of a compact side illumination system for lensless quantitative phase imaging.
• Utilizing multiplexed analog holograms to shape illumination and generate multiple (9) illumination angles.
• Experimental demonstration of the system's performance on phase samples.

Main Results:

• The proposed side illumination system reduces the overall height by an order of magnitude compared to conventional setups.
• The system provides an unobstructed view of the sample, facilitating easier manipulation and observation.
• Successful experimental imaging of phase samples was achieved with a field of view of approximately 17 mm².

Conclusions:

• The developed side illumination technique significantly simplifies and miniaturizes lensless QPI systems.
• This approach enhances the practicality and potential widespread adoption of QPI for biological imaging.
• The unobstructed view and large FOV capabilities make it suitable for observing dynamic cellular processes.