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Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements
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Phase-stable Doppler OCT at 19 MHz using a stretched-pulse mode-locked laser
Serhat Tozburun1,2,3, Cedric Blatter1,2, Meena Siddiqui2,4
1Harvard Medical School, Boston, Massachusetts 02115, USA.
Biomedical Optics Express
|March 16, 2018
Summary
We developed a fast, phase-stable swept-wavelength optical coherence tomography (OCT) system. This advanced OCT platform enables high-speed 4D Doppler imaging and angiography for preclinical perfusion studies.
Area of Science:
- Biomedical Optics
- Medical Imaging
- Optical Coherence Tomography
Background:
- Current optical coherence tomography (OCT) systems face limitations in speed and phase stability, hindering dynamic perfusion studies.
- Accurate Doppler imaging and angiography require precise synchronization and phase-sensitive measurements.
Purpose of the Study:
- To develop and demonstrate a novel swept-wavelength OCT system with enhanced speed and phase stability.
- To enable high-frame-rate 4D Doppler imaging and angiography for preclinical research.
Main Methods:
- Utilized a 19 MHz swept-wavelength laser source with stretched-pulse active mode-locking.
- Implemented electronic phase-locking for source, acquisition clock, and MEMS scanning mirrors (~23.8 kHz).
- Achieved 1.78 Gigasamples/sec acquisition using an external fixed clock for phase-sensitive imaging without k-clocking or calibration.
Main Results:
- Demonstrated phase-sensitive imaging without traditional synchronization or calibration methods.
- Successfully performed inter-frame and inter-volume Doppler imaging in mouse ear and brain.
- Achieved 4D acquisition rates of up to 100 volumes/sec (V-scans/s), enabling real-time angiography.
Conclusions:
- The developed swept-wavelength OCT system provides extremely fast and phase-stable measurements.
- This platform is suitable for advanced preclinical angiographic and Doppler investigations of perfusion dynamics.
- Offers a significant advancement for studying dynamic biological processes in vivo.
Keywords:
(140.3600) Lasers, tunable(170.0110) Imaging systems(170.4500) Optical coherence tomographyMore Related Videos
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