Compact, modular and in-plane AOSLO for high-resolution retinal imaging

Area of Science:

• Ophthalmology
• Optical Engineering
• Biomedical Imaging

Background:

• Adaptive optics scanning laser ophthalmoscopy (AOSLO) is crucial for retinal research.
• Previous AOSLO designs faced challenges with astigmatism and system complexity.
• Existing implementations utilize various optical arrangements, including planar and non-planar mirror systems, toroidal mirrors, or on-axis lenses.

Purpose of the Study:

• To present a new, compact, and modular AOSLO design.
• To eliminate astigmatism buildup in a planar optical alignment.
• To demonstrate diffraction-limited image quality and clear cone resolution.

Main Methods:

• Developed a novel AOSLO implementation using compact, reconfigurable modules based on an Offner relay system.
• Employed an off-the-shelf digital oscilloscope for data acquisition.
• Utilized custom Python code for image generation and analysis.

Main Results:

• The new design achieves a compact system with simple alignment.
• Maintained diffraction-limited image quality across the entire field of view.
• Clearly resolved cone photoreceptors in the central retina.

Conclusions:

• The modular Offner relay-based AOSLO design effectively overcomes astigmatism in a planar configuration.
• This system offers high-resolution retinal imaging and is adaptable for future component integration.
• The modular relay approach is broadly applicable to other point-scanned imaging systems.