Researchers Develop Optical Tomography System with BitFlow Frame Grabber to Better Diagnosis Eye Diseases

WOBURN, MA, MARCH 11, 2022 — High resolution 3D imaging of biological tissue is used extensively in the diagnosis of eye diseases, typically by applying a technique known as Optical Coherence Tomography (OCT). OCT testing has become a standard of care for the assessment and treatment of most retinal conditions. It is comparable to ultrasound, except that OCT employs light rather than sound and thereby achieves clearer, sharper resolution.
In a typical OCT system, an optical signal from a broadband source is divided into sample-arm and reference-arm signals using a beam splitter. Both signals are combined and an interference signal is detected by a detector assembly. Some systems employ a wavelength-tuning optical source and are termed “swept source” OCT (SS-OCT). Meanwhile, a system where a stationary broadband signal is dispersed spatially and detected using a spectrometer is referred as a Fourier Domain OCT (FD-OCT).
Both SS-OCT and FD-OCT techniques suffer from changes in the polarization of the optical signal when the signal is transmitted through materials possessing anisotropic properties, meaning they have a different value when measured from different directions. This results in artifacts that compromise the quality of the image, and therefore, the ability of doctors to diagnose a disease.
Reducing Polarization Artifacts Funded by Max-Planck-Gesellschaft and Massachusetts General Hospital, a team of researchers have developed a polarization insensitive detection unit (PIDU) for a spectrometer-based FD-OCT system that greatly minimized polarization associated artifacts in OCT images. The spectrometer unit employed diffraction grating (set at 1200 lines per mm), an 80mm lens, and a Sensors Unlimited InGaAs line-scan camera with a resolution of 2048 pixels.
Data from the spectrometer was collected at a line-scan speed of 100kHz utilizing a BitFlow Axion-CL Camera Link frame grabber. The Axion-CL supports a single Base CL camera, Power over Camera Link (PoCL), and can acquire up to 24 bits at 85MHz. The frame grabber benefits from a PCIe Gen 2 interface and a DMA optimized for fully loaded computers. Data collected by the Axion-CL was processed on LabVIEW software.
To demonstrate the proof of principle in biological tissue the researchers imaged chicken breast because of its high birefringence. Tests were conducted on the OCT system with and without the PIDU. During the imaging, the tissue was held in hand and maneuvered constantly to mimic real clinical conditions. Images were acquired and recorded for 10 seconds.
For the OCT system without PIDU, it was observed that the bright and dark bands of the sample were constantly fluctuating which can be attributed to the polarization dependent phase changes in the sample light. The OCT system with PIDU, however, showed that the image artifacts were not noticeable, making for images that are more accurate for a doctor to observe. Researchers found that in close examination, it was not only the light from the tissue that changes in intensity but also the light from the inner wall of the capsule which is not in tissue contact. This supports the idea that polarization artifacts come not solely from a tissue sample, but can also arise from the system itself.
The researchers believe their new design will be particularly useful in clinical settings where the sample arm is constantly under motion during probe introduction or when it is subjected to peristaltic motion. Further studies are planned on other biological tissues.
David Odeke Otuya, Gargi Sharma, Guillermo J. Tearney, and Kanwarpal Singh, “All fiber polarization insensitive detection for spectrometer based optical coherence tomography using optical switch,” OSA Continuum 2, 3465-3469 (2019)
Schematic of the FD-OCT system employing polarization insensitive detection scheme is shown. SMF: Single mode fiber, Cr: circulator, BS: beam splitter, PC: polarization controller, Co: collimator, NDF: neutral density filter, M: mirror, MPU: motor power unit, EC: electrical connection, MW: motor wire, PBS: polarizing beam splitter, OS: optical switch, G: grating, L: lens, LSC: line scan camera (Image courtesy of Otuya, Sharma, Tearney, and Singh)
(left) Image of chicken breast tissue acquired with OCT system without PIDU and (right) image of the same tissue acquired with OCT system with PIDU (Image courtesy of Otuya, Sharma, Tearney, and Singh)

BitFlow Axion-xB Frame Grabbers Improve Performance of Camera Link Imaging Systems

New frame grabbers acquire stable, low-latency data from CL Base Cameras

WOBURN, MA, FEBRUARY 2, 2021 — Design engineers in the machine vision industry now have more configuration options than ever before with the introduction of the new Axion-xB line of frame grabbers from BitFlow, with support for the highest performance Camera Link® Base cameras on the market. Available in single, dual and quad link versions for maximum design flexibility, the new frame grabbers demonstrate BitFlow’s ongoing commitment to the highly popular Camera Link (CL) standard.


“Axion-xB frame grabbers represent a major upgrade from our renown Neon family of CL frame grabbers that we are phasing out in favor of this faster, more economical design,” said Donal Waide, Director of Sales for BitFlow, Inc. “Today, we are making it much easier for developers to bring the power, acceleration and versatility of technologies we’ve incorporated in our high-end CoaXPress frame grabbers into a Camera Link system environment, including the BitFlow StreamSync DMA engine and buffer manager that eliminates the need for on-board memory.”

As data generated by faster, higher-resolution cameras continues to grow exponentially, the Axion-xB’s PCIe Gen 2 interface — with the DMA optimized for modern computers — is now in line with the rest of the Axion family. Features such as, easier switching between different tap formats, more powerful acquisition engine and a more flexible I/O and timing generator are all now readily available in a dedicated low cost CL Base orientated frame grabber.


NEON UPGRADE SOLUTION The Axion-xB line addresses the challenge to developers of delivering greater return on machine vision system investments. One way to add value is to upgrade to the Axion-xB from existing Neon frame grabbers. Moving from the Neon family to the Axion family is simple. No code alterations are required — designers just recompile with the latest BitFlow SDK (6.5). Or if a 3rd party application is installed, such as Cognex Vision Pro or LabVIEW, the user can download the latest driver from BitFlow and the program will be immediately supported.


BitFlow Axion-xB frame grabbers are complimented by a sophisticated application software package and the BitFlow SDK for Windows and Linux operating systems. They can be integrated with virtually every available software library to permit seamless custom application development.

BitFlow Reaches for the Stars Helping Mount Wilson Observatory Capture Celestial Images

WOBURN, MA, JANUARY 7, 2021 — Located on Mount Wilson, California, Georgia State University’s Center for High Angular Resolution Astronomy array (CHARA) is the world’s largest optical interferometer and has delivered landmark sub-milliarcsecond results in the areas of stellar imaging, binaries, and stellar diameters. CHARA is comprised of six separate telescopes across Mount Wilson that act together as one enormous telescope to attain the resolving power to define amazingly small details. To operate, the light obtained from each telescope is combined and a final reconstructed image can be observed that is of far higher resolution than would otherwise be possible.

Achieving observations of faint targets such as young stellar objects and active galactic nuclei required a new higher sensitivity adaptive optics system to correct atmospheric turbulence and path aberrations between the six telescopes in the array and the beam combiner lab. A BitFlow Neon CLB was used in the optics system as a low-latency frame grabber solution for the Andor iXon Ultra 897 EMCCD cameras capturing light from each telescope. The frames are then written to an instrument shared memory to be accessed directly by the main wavefront sensor server for processing and analysis.

Simple and affordable, the Neon CLB is a Base/PoCL Camera Link frame grabber that acquires images up to 24 bits at 85 MHz. It is one component in CHARA’s entirely commercial off-the-shelf (COTS) system. In all, the optics system features six Andor ENCCD cameras, six frame grabbers, 12 OKO MMDM deformable mirrors, and six Intel CPU 6 core computers, one for each telescope. The fundamentals of the computers and the BitFlow frame grabbers are identical, meaning they use the same motherboard, processor, and RAM. Other frame grabbers were originally tested by the system designers but the latency jitter was too high compared to the BitFlow Neon CLB. In addition, the BitFlow grabber worked ideally with the Andor iXon Ultra 897’s non-standard Camera Link out: base configuration, 3-tap interface and 16-bit greyscale.

Using the BitFlow frame grabber, the cameras now operate at a 440Hz measured frame rate and have a -3dB closed-loop bandwidth of 19Hz. This is a similar performance to the adaptive optics system of the Auxiliary Telescopes of the VLTI (Very Large Telescope Interferometer) at the Paranal Observatory in Chile which is so powerful that it can detect an astronaut on the moon.

According to the CHARA researchers, the initial on-sky tests of the optics system have been very promising with more than a magnitude sensitivity improvement. In addition to observations of faint young stellar object disks and active galactic nuclei, researchers are using it to observe celestial objects in weather conditions that previously were not possible.

CAPTION: Georgia State University’s Center for High Angular Resolution Astronomy array on Mt. Wilson is the world’s largest optical interferometer
CAPTION: BitFlow Neon CLB is being used as a low-latency frame grabber solution for the CHARA array

Neon-DIF Frame Grabber is BitFlow’s Upgrade Solution to Older Machine Vision Systems Running Differential Cameras

Neon DIF

Older machine vision systems are difficult and costly to upgrade, especially those based on RS422 and low-voltage differential signaling (LVDS) type interfaces. Incompatible with most modern frame grabbers, these legacy differential systems can now be brought up to speed using the BitFlow Neon-DIF differential frame grabber. Designed on the latest PCI Express (PCIe) platform, the Neon-DIF will upgrade an older differential system to acquire images up to 32 bits at 85 MHz from an existing LVDS camera, providing greater control, plus the convenience of running on Windows 10 or Linux OS.

“There are thousands of older differential systems today that handle basic processes at minimal cost, such as mail sorting, package handling, X-ray imaging, Focused Ion Beam, and Scanning Electron Microscopes. Unfortunately, users can’t upgrade the system’s PC to one featuring more powerful processing and a newer OS because the original PCI frame grabber is no longer available or isn’t compatible with a new PC,” explained Donal Waide, Director of Sales for BitFlow, Inc. “Our Neon-DIF frame grabber enables the user to save money by keeping the same LVDS line or area scan cameras, devices and application, yet upgrade their PC to use faster, more accurate image processing algorithms.”

Rather than PCI, the Neon-DIF is built on a half-size x4 PCIe bus interface that fits into the x16, x8, x4 and x1 slots found in today’s PCs. It installs fast and simple, bringing to an existing system a full set of new control signals and sync inputs for total camera and acquisition control.

Upgrades BitFlow Road Runner and R3-DIF
Along with older PCI frame grabbers from other manufacturers, the Neon-DIF provides an upgrade path for users of BitFlow Road Runner and R3-DIF PCI frame grabbers. It has the same connector pin-out and is compatible with their cables.

Ideal for Differential System OEMs
Besides legacy situations, the NEON-DIF is a cost-effective PCIe choice for OEMs developing new systems featuring cameras or other devices that output differential data. The Neon-DIF can acquire from just about any device and efficiently DMA its data into host memory at rates of 528 MB/S.

BitFlow SDK Support
The Neon-DIF is supported by the BitFlow SDK for both 32-bit and 64-bit Windows platforms. The SDK offers drivers, DLLs, and configuration utilities for people interested in using third party software. For those customers interested in developing their own applications, the SDK has header files, libraries, and example code for Windows XP/2003/Vista/Windows 7/10.

BitFlow Frame Grabber Eliminates Data Bottlenecks in New Optical Mapping Platform

New approach opens up dual mapping technology to broader cardiovascular research community

WOBURN, MA, OCTOBER 19, 2020 — Optical mapping is an imaging technique that measures fluorescence signals across a cardiac preparation with high spatiotemporal resolution. Optical mapping of transmembrane voltage and intracellular calcium is a powerful tool for investigating cardiac physiology and pathophysiology.

Researchers at the Sheikh Zayed Institute for Pediatric and Surgical Innovation, Washington, DC, recently introduced a novel, easy-to-use approach to optical mapping that requires only a path splitter, a single camera, a frame grabber and an excitation light to simultaneously acquire voltage and calcium signals from whole heart preparations.1 This cost-effective yet highly reliable system eliminates the need for multiple cameras, excitation light patterning, or frame interleaving, therefore aiding in the adoption of dual mapping technology by the broader cardiovascular research community, and decreasing the barrier of entry into panoramic heart imaging.

At the heart of the new system is a BitFlow four-channel frame grabber. It is used for imaging control and acquisition from an Andor Zyla 4.2 PLUS Scientific CMOS (sCMOS) camera acquiring images at 4.2 megapixels. A 10-tap CameraLink™ connection with a clock rate of 85 MHz was necessary to achieve the fastest frame rates possible. The researchers selected the BitFlow frame grabber in part because of its “2x” mode that shares DMA responsibility between two DMA engines, effectively doubling the frame grabber’s bandwidth and providing much needed headroom to DMA images from the camera continuously, regardless of system load. Because of the high data rate of acquisition — due to high spatial and temporal resolution and bit depth — an NVMe SSD disk was also essential for reducing data rate bottlenecks.

To achieve optimal results, an image splitting device is positioned in front of the sCMOS camera. A fixed focal length 17 mm/F0.95 lens is attached to the front of the device for experiments with rat hearts, while a wide-angle 6mm f/1.2 lens is used for pig hearts. To guide manual alignment, MetaMorph software from Molecular Devices overlays live images as contrasting colors or as subtractive grey scales to highlight misalignment. With this live feedback, images are quickly aligned using the “long” and “short” control knobs. After alignment, any standard image acquisition software can be used such as MetaMorph, μManager, or Solis. The acquired image includes two fields which can be separated using imaging software that includes automated tools.

The computer consisted of a Xeon CPU E3–1245 v5 3.50 GHz (Intel corporation), 32 GB of RAM, and a non-volatile memory express solid state disk (NVMe SSD, Samsung 960 Pro). Notably, the platform is composed entirely of off-the-shelf components, which will help in the adoption and successful implementation of this setup by other laboratories.

Visit www.bitflow.com for more information.

1. Jaimes, R., McCullough, D., Siegel, B. et al. Lights, camera, path splitter: a new approach for truly simultaneous dual optical mapping of the heart with a single camera. BMC biomed eng 1, 25 (2019). https://doi.org/10.1186/s42490-019-0024-x

Photo caption: A Optical system configuration with image splitting device positioned in front of a sCMOS camera. B Emission of each complementary probe (Vm, Ca) is separated by wavelength using an image splitting device. C Dichroic cube setup with the two emission filters and a dichroic mirror. 

BitFlow Introduces SDK for NVIDIA Jetson AGX Xavier Development Kit

Jetson with a Claxon

BitFlow has released a Linux AArch64 (64-bit ARM) SDK that enables seamless integration of BitFlow frame grabbers with the NVIDIA Jetson AGX Xavier Development Kit. 

Donal Waide, Director of Sales for BitFlow, states, “Many of our customers are already using GPU solutions such as NVIDIA for image processing so adding this option to the already large BitFlow suite of adapters was a natural progression for the company. BitFlow has been supporting Linux for several years across a variety of flavors.”

Added Waide, “BitFlow was one of the first frame grabber companies to support NVIDIA’s GPUDirect for Video technology. BitFlow and NVIDIA have worked together for a number of years already.” 

With the advent of the new machine vision standard CXP 2.0 where data rates are now up to 50 Gb/S, customers are looking to process more and more data and in shorter timeframes. For this, a GPU can typically perform these tasks much more effectively than a CPU. Even with slower data rates such as Camera Link’s (up to 850 MB/S) the ability to quickly process more complex algorithms is equally important. 

The NVIDIA Jetson AGX Xavier is the first computer designed specifically for autonomous machines. It has six Engines onboard for accelerated sensors data processing and running autonomous machines software, and offers the performance and power efficiency for fully autonomous machines.

BitFlow in San Jose, California 2019

BitFlow will be exhibiting at the CRAV conference at the DoubleTree by Hilton San Jose from Tuesday November 12th through Wednesday November 13th.  Come stop by tabletop #63 to see our latest offerings.

BitFlow in Munich, Germany 2019

BitFlow will be exhibiting at Laser World of Photonics in Munich from June 24th through June 27th.  Come visit us in Hall B2 Booth 127-3 to see our latest products!

Vision 2018, Stuttgart, Germany, November 6-8, 2018

BitFlow recently exhibited at Vision in Stuttgart, Germany.

Our latest released CoaXPress frame grabber, the Claxon, was on display.  The Claxon, which can run at up to 12.5 Gb/S, is our CXP-12 frame grabber which will be available in Q2 2019.

A demo showcasing our Cyton CXP4 with 4 single channel CXP cameras was on display.  These cameras were focused in on our Aon-CXP, single link frame grabber.  Cameras on display included ISVI, CIS, Adimec and Sentech.

The Cyton CXP HALCON demo was front and center catching the attention of many attendees.

Located in Hall 1 Aisle A we had a prime location for lots of booth traffic.

If you attended the show and did not get a chance to stop by our booth, please visit us online, submit an inquiry or give us a call at 781-932-2900.

BitFlow at CRAV in Santa Clara, CA 2018

BitFlow recently exhibited at the AIA CRAV conference at the Hyatt Regency in Santa Clara, California.

Cameras from ISVI, CIS, Adimec and Sentech were used in a demo highlighting our Cyton-CXP4.

Our BitBoxAxion-CLAon-CXPand Cyton CXP4 were all on display.

If you attended the show and did not have a chance to stop by tabletop #3, please visit us online, submit an inquiry or give us a call at 781-932-2900.