Abstract
Purpose :
To develop a high-speed engine for imaging the structure and function of the retina and cornea within the living eye.
Methods :
The schematic of the swept-source OCT system is shown in Fig. 1 (a-c). The system uses a vertical cavity surface emitting laser (VCSEL) as the light source, which has an A-scan sweep rate of 400 kHz and an 10db bandwidth of 100 nm centered at 1060 nm. The laser has a total power of 17.5 mW. The system contains four 2×2 couplers, and the power at the pupil is 3.6 mW after passing through the couplers and connectors. The system uses a data acquisition card (PCIe 6361, National Instruments) to generate the control signals for the scanners and a high-speed digitizer (ATS9371, Alazar Tech.) to acquire the signal from the balanced detector. A high-performance graphics card (RTX4060, NVIDIA) is used to speed up the processing of OCT data for real-time display.
Results :
In Fig. 1 (d), the system calibration results were depicted, showcasing a sensitivity of approximately 110 dB and a dynamic range of about 55 dB. Using FFT without zero-padding on the A-scan, the axial pixel size is approximately 5.2 µm/pixel. The system achieves an axial resolution of approximately 7.6 µm in air, offering an imaging depth range of 2 mm in the same medium. The human retina and cornea are illustrated in Fig. 1 (e) and (f) respectively, providing exemplary images captured by the system.
Conclusions :
A high-speed OCT system for imaging the living retina and cornea was developed. Functional technique to image the Cornea using Optical Coherence Elastography is going to be integrated as well.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.