Optical phase modulation by natural eye movements: application to time-domain FF-OCT image retrieval

Area of Science:

• Ophthalmic imaging
• Biomedical optics
• Optical coherence tomography

Background:

• Ocular motility is typically an impediment to high-resolution ophthalmic imaging.
• Existing methods often require complex synchronization systems.

Purpose of the Study:

• To investigate the use of natural in vivo human eye movements for optical phase modulation.
• To develop a simplified time-domain full-field optical coherence tomography (TD-FF-OCT) system.
• To retrieve tomographic images by utilizing ocular motion.

Main Methods:

• Utilized natural axial eye movements to modulate optical phase.
• Employed time-domain full-field optical coherence tomography (TD-FF-OCT) for tomographic image retrieval.
• Acquired in vivo human corneal images using 2-phase and 4-phase retrieval schemes with varying exposure times (3.5ms, 10ms, 20ms).
• Analyzed eye movement data from spectral-domain OCT with axial eye tracking (180 B-scans/s) to assess ocular motion's impact on image quality.

Main Results:

• Demonstrated successful retrieval of tomographic images by harnessing natural eye movements.
• Showcased in vivo human corneal imaging capabilities.
• Identified optimal combinations of camera acquisition speed and piezo modulation amplitude for high-signal tomographic images without phase washout.

Conclusions:

• Natural eye movements can be effectively utilized to simplify ophthalmic TD-FF-OCT devices, eliminating the need for piezo motor-camera synchronization.
• This approach offers a pathway to more accessible and streamlined ophthalmic imaging solutions.