Computational aberration correction in spatiotemporal optical coherence (STOC) imaging.

Area of Science:

• Biomedical Optics
• Optical Imaging
• Ophthalmology

Background:

• Fourier-domain full-field optical coherence tomography (FD-FF-OCT) is susceptible to coherent crosstalk noise.
• Spatiotemporal optical coherence (STOC) imaging utilizes time-varying phase masks to modulate light and alter interferometric signals.
• Standard FD-FF-OCT processing involves averaging interference images to generate volumetric OCT images.

Purpose of the Study:

• To introduce and validate Spatiotemporal optical coherence (STOC) imaging for noise reduction in FD-FF-OCT.
• To demonstrate the advantages of coherent averaging over incoherent averaging in STOC imaging.
• To show the capability of STOC imaging with coherent averaging for aberration correction in OCT.

Main Methods:

• Implementing time-varying inhomogeneous phase masks to modulate incident light in both interferometer arms simultaneously.
• Applying coherent averaging to the modulated interference images.
• Utilizing computational phase correction to compensate for geometrical aberrations.
• Imaging the photoreceptor layer of the human retina.

Main Results:

• STOC imaging effectively suppresses coherent crosstalk noise in FD-FF-OCT.
• Coherent averaging preserves lateral phase stability of the modulated signal.
• Computational phase correction successfully compensated for geometrical aberrations.
• Otherwise invisible photoreceptor mosaics were revealed in the human retina images.

Conclusions:

• Coherent averaging is suitable for STOC imaging when phase modulation occurs in both interferometer arms.
• STOC imaging with coherent averaging enables robust aberration correction for enhanced OCT image quality.
• This technique significantly improves visualization of microstructures like retinal photoreceptor mosaics.