Multi-channel swept source optical coherence tomography concept based on photonic integrated circuits.

Area of Science:

• Photonics
• Biomedical Imaging
• Optical Coherence Tomography

Background:

• Photonic integrated circuits (PICs) offer miniaturization and integration potential for advanced optical systems.
• Current PIC-based swept-source OCT systems face challenges with excess loss and limited parallelization.
• Efficient path routing is crucial for enhancing the performance of OCT systems.

Purpose of the Study:

• To introduce a novel concept for a multi-channel swept-source OCT system utilizing PICs.
• To demonstrate a low-loss polarization-dependent path routing approach for parallelized OCT measurements.
• To validate the concept through a single-channel system and analyze its potential for speed enhancement.

Main Methods:

• A silicon nitride PIC was fabricated using CMOS-compatible plasma-enhanced chemical vapor deposition.
• A single-channel swept-source OCT system operating at 840 nm was implemented as a proof of concept.
• In-vivo human retinal tomograms were acquired to demonstrate system functionality.

Main Results:

• A low-loss polarization-dependent path routing approach was successfully implemented.
• The fabricated PIC enabled the acquisition of high-resolution retinal images.
• Performance analysis indicates a potential tenfold increase in acquisition speed for a multi-channel system.

Conclusions:

• The proposed PIC-based multi-channel swept-source OCT concept enables efficient parallelization.
• The low-loss path routing is key to achieving significant speed improvements in OCT systems.
• Future monolithic co-integration with electronics promises further advancements in OCT technology.