Analytical Technologies Singapore

imaging

LaVision published a paper about the novel Object-aware Lagrangian Particle Tracking (OA-LPT) scheme in the Measurement Science and Technology journal

The measurement of flows around objects such as cars, airfoils and maritime structures often poses major challenges for optical flow diagnostics methods such as Tomo-PIV or Lagrangian Particle Tracking (LPT)/Shake-the-Box (STB) within the measurement fields. Also, many flow reconstruction algorithms simply do not have the capabilities of incorporating such object information.


For this reason, measurements are often limited to observations directly behind the object (characterization of wake flows) or to the stitching of averaged flow fields in sub-sampled regions in order to avoid having negative impacts on the measurement data.


To solve this practical problem, LaVision introduces the novel Object-aware Lagrangian Particle Tracking (OA-LPT) method to seamlessly integrate the knowledge about the presence of view-obstructing objects in the measurement domain during the 3D particle reconstruction.
It minimizes the occurrence of reconstruction artifacts and provides a measurement approach for instantaneous 360° LPT/STB measurements around the objects of interest.

LaVision published a paper about the novel Object-aware Lagrangian Particle Tracking (OA-LPT) scheme in the Measurement Science and Technology journal Read More »

LaVision launches the next generation of PIV cameras – the Imager CX3p Camera Series!

All the advantages of the Imager CX3 camera series, which was successfully introduced last year, were the basis for this further development.

The small and compact cameras of the Imager CX3 camera series, which are equipped with the innovative back-illuminated technology that enables incredible sensitivity and very low noise, have already been a resounding sales success. The small pixels enable very small fields of view for a given lens, and the hardware binning guarantees exceptional frame rates and therefore increased flexibility when using these cameras.

LaVision is now launching the unique Imager CX3p camera series, which is equipped with an integrated Scheimpflug mount for adjusting the angle between camera and lens (Scheimpflug angle) for C-mount and F-mount lenses.This ensures quick and easy alignment of the viewing direction, Scheimpflug angle and sensor orientation.

The integrated Scheimpflug mount offers three independent setting options for tilt, rotation and sensor orientation. All settings are supported by an intuitive DaVis software tool resulting in very quick and easy Scheimpflug adjustment.

Here you can watch our video, showing the easy handling of this camera with all its Scheimpflug settings as well as the adjustment of the Scheimpflug mount supported by our user-friendly DaVis software tool.

LaVision launches the next generation of PIV cameras – the Imager CX3p Camera Series! Read More »

Detonation Analysis by using the Solid-State-Streak-Camera S3C-1

Visualisation of Detonation Front Curvature with Nanosecond Temporal Resolution

The chemical reaction inside a homogeneous explosive agent can be initiated at a small spot and will then propagate spherically from this spot. The propagation can be observed as optical emission at the interface between the explosive and the air. Measurement along only one line is sufficient, but must be recorded with high temporal resolution in the nanosecond range to capture fast reactions. The spherical propagation leads to the curvature of the detonation front. The emission is expected to start in the center of the line and then propagate symmetrically along the line toward the edges. The analysis of this curvature allows the determination of the dynamic processes inside the explosive.

Instead of using a conventional tube-based streak camera, the solid state streak camera S3C-1 is used. The propagation of the optical emission is completed within 2 µs and the S3C-1 allows to capture this with 10 ns temporal resolution. A post trigger feature of the S3C-1 is used to capture the emission without being affected by the strong jitter of the detonator. An application note describes the setup and experimental details. It is available on request.

Detonation Analysis by using the Solid-State-Streak-Camera S3C-1 Read More »

Supersonic Electrical Discharge in Water

Researchers at Loughborough University have been using a SIMX framing camera at frame rates up to 100 million frames / second to capture the initial stages of supersonic electrical discharges driven by nanosecond rise time, high-voltage ( 100 kV) impulses applied across a pair of electrodes mounted in water.

This research in high voltage breakdown in water, has progressed our understanding of how high-power ultrasound waves generated in a liquid by a high-voltage pulsed source can be used for industrial applications such as rock fracturing or in the medical or food industry domains to kill bacteria in a sterilisation process. The SIM camera was contained within a Faraday cage and viewed the electrodes mounted in a water tank. Pressure variation with different voltage rise times and interelectrode gaps were measured using a set of hydrophones placed 0.5m from the source.

This sequence shows results for an electrode gap of 3 mm and voltage rise time of 30 ns which corresponded to a streamer propagation speed of 63 Km/s and a peak pressure of 0.25 MPa.

Consistent peak pressures between 0.1 MPa and 1.1 MPa were found for inter-electrode gaps between 1 mm and 12 mm. The research concluded that the inter-electrode gap had a significantly greater effect on peak pressure than rise time for the same input energy.

The SIM camera’s nanosecond timing accuracy provided the flexible delays and exposure times required to capture and freeze the motion of these extremely fast events. To accommodate the different illumination conditions required to see both the source electrodes and the event, the camera control software “image merge” feature was used to overlay a static sequence, which used longer exposure times, with the dynamic sequence which used much shorter exposure times.

These merged images provide context and the relative positions of the event and electrode for all the tests.

Congratulations to Jessica Stobbs for receiving the EAPPC (Euro-Asian Pulsed Power Conference, Seoul, S. Korea, 2022) outstanding Young Researcher Award with this research.

Supersonic Electrical Discharge in Water Read More »

Triggering for microsecond accuracy

Accurate triggering of framing cameras to capture fast events is one of the crucial aspects of high-speed imaging. Adding more instrumentation such as streak cameras and flash illumination can lead to a complex array of instrumentation, particularly when it comes to synchronising all aspects of data capture for one single microsecond timescale event.

Specialised Imaging’s SIM framing cameras can greatly simplify this trigger synchronisation process, with a built-in timing generator and control software to set up trigger outputs to these external devices.

If a streak camera is used to capture the same event it can be connected to the SIM’s (optical) auxiliary port and connected to the SIM’s trigger output to allow the streak camera trigger delay adjustment via the SIM camera control software. Any flash illumination can be connected to the SIM’s dedicated flash trigger (output) connection for timing adjustment also using the camera control software.

This application note describes how a SIM camera was used to capture energetic events, where microsecond accuracy was required. The SIM camera was used to trigger synchronise a streak camera and flash unit to capture images for detonator case expansion and tip velocity measurement.

Read the application note

Camera: SIMX-8 Resolution: 1280×960 px Exposure time: 100nS Interframe time: 4.27uS Frame Rate: 234K FPS Event: Detonator Illumination: Back illumination – AD500mage: New and old SIM (8 channel) camera design

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Streak / Framing Camera Provides Unique Insight into Nano Events

Researchers on several projects have successfully used Specialised Imaging Simultaneous Multichannel Framing Camera and Streak Camera Systems to provide unique insights into an ultra-fast events.

Specialised Imaging ultra-fast camera systems offer scientists involved in electrical discharge, biomedical and energetic events research the potential to simultaneously record framing images and streak images.

Ultra-fast imaging and simultaneous streak image capture offers a unique insight into transient events that cannot be achieved with single-point measurements. Ultra-fast framing images show extremely detailed two-dimensional spatial information about the event, whereas the streak image is a continuous one-dimensional record with picosecond temporal resolution. When combined these images provide a unique visualisation of transient nanosecond timescale events.

Specialised Imaging’s system enables researchers to couple a streak camera directly into the same optical path used in their SIM ultra-fast framing cameras. This innovation allows for the capture of framing and streak data on the same event using the same optical path for direct correlation of 2D and streak image data. The combination streak and framing camera has allowed researchers to attain higher performance levels using dual camera systems with different optical inputs. Benefiting from using a common optical input and dedicated output window, the Specialised Imaging Simultaneous Multichannel Framing Camera and Streak Camera system drastically simplifies optical set up and eliminates perspective distortion (parallax errors). Beneficially, the set-up also allows use of an existing streak camera which can still be used independently.

Capable of capturing data at 1 billion frames per second, the SIM range of ultra-fast framing cameras offer the ultimate in ultra-high-speed imaging performance to scientists and engineers across all disciplines. The proprietary optical design of SIM cameras offers up to 32 images without compromising shading, or parallax. High resolution intensified CCD sensors controlled by state-of-the-art electronics provide almost infinite control over gain and exposure to allow researchers the flexibility to capture even the most difficult phenomena. In addition to enabling simultaneous streak and framing experiments, the optical port on the SIM camera can be used to couple high-speed video cameras for longer record durations, or to integrate a mass spectrometer for hyperspectral

Case Study

Researchers at the University of Michigan used a Specialised Imaging Simultaneous Multichannel Framing Camera and Streak Camera System to capture images of bursting microscopic droplets releasing the fluid within by focused ultrasound, and ultimately understand how this process can safely and effectively be applied to the delivery of drugs within the body.

Read the case study

Application Note

Ultra-high Speed Framing and Streak Camera Imaging of C4 Explosive

The University of Rhode Island used a Specialised Imaging Simultaneous Multichannel Framing Camera and Streak Camera System in research to quantify the shock speed and qualify the axisymmetric detonation development of a C4 booster test piece.

Read the Application Note

Streak / Framing Camera Provides Unique Insight into Nano Events Read More »