Axial-lateral parallel time domain OCT with optical zoom lens and high order diffracted lights for variable imaging...

Area of Science:

• Biomedical Optics
• Optical Imaging
• Medical Technology

Background:

• Time-domain optical coherence tomography (TD-OCT) is crucial for non-invasive imaging.
• Adjusting measurement ranges in TD-OCT systems can be challenging.
• Existing methods may lack flexibility in adapting to different imaging depths and widths.

Purpose of the Study:

• To develop an axial-lateral parallel TD-OCT (ALP TD-OCT) system with adjustable measurement ranges.
• To enhance imaging flexibility by enabling continuous lateral and discrete axial range adjustments.
• To demonstrate the system's capability for in vivo imaging.

Main Methods:

• Utilized an optical zoom lens for continuous lateral range adjustment (4-8 mm).
• Employed high-order diffracted lights from a reflective diffraction grating for discrete axial range adjustment (1st-4th orders).
• A 2-D camera captured depth-resolved interference images without axial/lateral scans, using diffracted light as a reference beam.

Main Results:

• Achieved continuous lateral range adjustment from 4 to 8 mm.
• Demonstrated discrete axial range adjustment using 1st to 4th order diffracted lights.
• Generated OCT images (320x256 pixels) at 30 fps with high sensitivity (94.6 dB).
• Successfully imaged a human finger in vivo.

Conclusions:

• The developed ALP TD-OCT system effectively adjusts measurement ranges using an optical zoom lens and diffracted light orders.
• The system offers enhanced flexibility for various imaging applications.
• The high sensitivity and frame rate enable efficient in vivo imaging.