Abstract
Purpose :
Acquiring simultaneous OCT images from dual sample planes is helpful in multi-directional imaging (angle independent Doppler, speckle reduction), spatially multiplexed imaging (multiple fields of view or depths), and potentially two separate samples (whole eye or binocular imaging). However, if done simultaneously, dual sampling requires complex custom control, coordination, and processing. The arrival of Vortex, an open-source OCT software library, makes available a flexible, high-performance OCT software environment that accommodates custom OCT acquisitions, processing, and displays, as well as support for auxiliary hardware that may be used in research systems. Here we use Vortex to enable optimized B-scan interlaced switching between two sample arms and a single source and detector with real-time de-interlaced display and storage of the two samples.
Methods :
Control software was written in Python 3 with a user interface designed using PyQt5. Vortex provided the core OCT functionality and enabled modular and powerful OCT system design. PySerial library was used for serial communication with external hardware. Development hardware consisted of a NI PCIe-6351 with a BNC-2110 breakout board (Hardware IO), Alazar ATS9373 (Acquisition), and Axsun 100kHz swept source laser. An electrically controlled 2x1 fast fiber optic switch (BATI) was used to switch between 2 telecentric sample arms (Fig. 1). We evaluated our software by imaging an IR card concurrently with a cornea phantom. Screenshots were captured at various time points during the scans (Fig. 2).
Results :
Our Vortex application was able to acquire two independent scans at once by switching between each at B-scan scale. Furthermore, it was flexible enough to process these two interlaced scans separately and to create two separate de-interlaced displays at the same time (Fig. 2). It also produced synchronized digital outputs from the NI card for the purpose of controlling the fiber switch.
Conclusions :
We demonstrated here control and processing of a rapidly switched OCT dual sample arm acquisition using the Vortex open-source OCT software library. The Vortex library provides a common platform for control of complex, custom research OCT systems such as for dual sampling.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.