Swept-Source OCT: easy software development kit integration

Since 2014, Acqiris has developed data acquisition hardware (digitizers) and software for medical and industrial systems based on Swept-Source Optical-Coherence-Tomography (SS-OCT).

Acqiris AQOCT Solution primarily addresses the specific data acquisition and OCT signal processing needs for Swept-Source OCT applications. Acqiris AQOCT offers:

High image resolution for an optimal contrast
Fast sampling rate to achieve a larger imaging depth range (SW programmable imaging depth)
Digital real-time K-space re-mapping approach for artifacts-free images
X-Y embedded Galvo scanner control for more compact and tightly synchronized systems
Support of high laser source sweep rate for faster images
Engineering service for support and customization.

Based on high-speed DAQ cards/modules and a complete and flexible real-time OCT engine embedded in the FPGA, the AQOCT solution allows the acquisition and processing of both OCT and K-clock signals, delivering fast and accurate OCT images.

Acqiris AQOCT Solution package includes:

DAQ card or module (with PCIe form factor or an enclosure with USB-c Thunderbolt 3 interface)
OCT applicative Firmware for real-time processing in the FPGA
Associated Software Suite: device drivers and the SW tools required to install, operate, and maintain the AQOCT solution within your system.

Besides, Acqiris proposes a Software Development Kit to make integration easier within your specific system environment. It contains all the required SW components, programming examples, a dedicated graphical user interface and allocated support.

AQOCT Solution Overview

Key features

A-scan rate: from 100 kHz to 2 MHz
1 or 2 OCT channels
K-clock digital remapping
Resolution from 8-bit to 14-bit ADC, enabling better contrast
High Signal-Noise Ratio (SNR) for improved sensitivity
Deeper analysis thanks to a high sampling rate of up to 4GS/s
Programmable analysis depth

OCT engine

OCT signal processing in the FPGA
Flexible real-time processing
Up and down sweep support
Support of custom processing

Image quality and clarity

Dynamic K-space re-mapping approach
Exclusive proprietary ICs and IPs enabling excellent signal performances, image details, depth, contrast, and acquisition speed
Unique real-time internal trigger time interpolator enabling a high trigger resolution and a precise and accurate phase measurement

Acqiris'Solution improves the final image clarity and quality, optimizing your complete SS-OCT system.

K-space re-mapping approach

Minimizing artifacts & simplifying design

With the K-space re-mapping approach, both OCT-signal and K-clock waveforms are sampled by an independent low-jitter and stable fast clock synthesized on the ADC card.

Digital K-space remapping process:

Extraction of the K-clock signal phase
Re-mapping of the digitized OCT signal in K-space, based on the K-clock phase.
Digital fractional re-sampler

Advantages of K-clock re-mapping vs. "traditional" direct clocking:

No need for a dummy clock
Minimizing artifacts: No artifacts coming from direct ADC clocking with variable frequency clocks and temperature induced effects
Configurable analysis depth
Support of higher A-scan rate
ADC sampling rate constant and independent from K-clock frequency (K-clock range 100-900 MHz)
Light source flexibility (less dependency on matching k-clock frequency)
Full flexibility and control: For example, the possibility to digitally compensate the optical path difference between K-clock and OCT-signal

OCT engine and flexible real-time signal processing

The OCT processing steps are implemented in the module’s FPGA:

Programmable FIR on both channels
Fractional re-sampler for K-space remapping
Background subtraction
Programmable Windowing/Dispersion compensation
FFT with complex/magnitude/phase output
Adjacent A-scans averaging

You can choose to perform all or only part of the processing steps, depending on your application, your existing software components and your own experience.

Phase-sensitive applications are supported: phase and magnitude can be red simultaneously.

Quick and Easy Integration

AQOCT Development Package

API dedicated to SS-OCT allows the control of all programmable features of the DAQ card and the dedicated real time OCT processing
Project and example for Python and C++ compatible with Visual
Dedicated OCT Graphical User Interface
Support and remote sessions to fasten the setup of your system.

Integrated Scanner control

Acqiris DAQ solution offers the possibility to control the scanner/galvo X,Y positioning without the need of external electronics.

The analog outputs allow for synchronization of the scanner, the OCT-source laser, and the OCT processing. A control signal can be configurated, enabling XY sweeps and galvo positioning (predefined or custom patterns can be generated).

Download the Acqiris Solution description for more details: