Single fiber confocal microscope with a two-axis gimbaled MEMS scanner for cellular imaging

Area of Science:

• Biomedical optics
• Microscopy
• Optical engineering

Background:

• Confocal microscopy offers high resolution but often requires bulky, complex systems.
• Miniaturization of optical systems is crucial for in vivo and point-of-care applications.
• Fiber-based imaging provides flexibility and access to difficult-to-reach areas.

Purpose of the Study:

• To develop and characterize a compact, single fiber reflectance confocal microscope.
• To evaluate the imaging performance, including resolution and speed.
• To demonstrate its capability for visualizing sub-cellular structures in biological samples.

Main Methods:

• A single fiber reflectance confocal microscope was designed and constructed.
• A two-dimensional MEMS (Micro-Electro-Mechanical System) gimbaled scanner was integrated for beam steering.
• Lateral and axial resolutions were measured using standard calibration targets.
• Imaging speed was assessed, and video acquisition was performed.

Main Results:

• Achieved a lateral resolution of 0.82 µm and an axial resolution of 13 µm.
• The microscope operates at 8 frames per second with a field of view of 140 x 100 µm.
• Sub-cellular resolution images and videos of cell phantoms and biological tissue were successfully acquired.

Conclusions:

• The developed single fiber confocal microscope offers high-resolution imaging capabilities in a compact form factor.
• The system demonstrates potential for in vivo microscopy and pathological analysis.
• MEMS scanner integration enables efficient beam steering for versatile imaging applications.