Ultra-compact silicon photonic integrated interferometer for swept-source optical coherence tomography.

Area of Science:

• Photonics
• Biomedical Engineering
• Optical Imaging

Background:

• Optical Coherence Tomography (OCT) is a crucial non-invasive imaging technique.
• Swept-source OCT (SS-OCT) offers advantages in imaging depth and speed.
• Miniaturization of OCT components is essential for portable and advanced systems.

Purpose of the Study:

• To demonstrate an ultra-compact silicon integrated photonic interferometer for SS-OCT.
• To evaluate the performance of this integrated interferometer in an SS-OCT system.
• To explore potential improvements for silicon photonic integrated circuits in OCT.

Main Methods:

• Design and fabrication of a silicon photonic integrated interferometer with a footprint of 0.75×5 mm².
• Integration of the photonic circuit into an SS-OCT system.
• Characterization of system sensitivity and demonstration of cross-sectional imaging.

Main Results:

• Achieved an ultra-compact integrated interferometer size.
• Measured system sensitivity of -62 dB with 115 μW sample power.
• Successfully demonstrated cross-sectional OCT imaging of a layered tissue phantom.

Conclusions:

• The developed silicon integrated photonic interferometer is suitable for SS-OCT systems.
• The compact design facilitates potential for miniaturized and portable OCT devices.
• Further advancements in silicon photonics can enhance SS-OCT performance.