How fast X-ray pulses capture dynamic events
Photo: Courtesy Fraunhofer EMI
High-speed image
sequences reveal motion
The time it takes to record an X-ray image depends upon the intensity of the X-ray tube. With a low intensity tube, you can easily capture static images. But, what if you want to capture dynamic events that are happening super fast and can’t be seen by the human eye? Then you’re going to need really fast pulses of X-rays.
With each X-ray pulse generated, you can capture one image and the images can be assembled in sequence to illustrate motion. This is referred to as chronophotography.
Chronophotography dates back to 1878 when Eadweard Muybridge created “The Horse in Motion” which depicted a horse with all four hoofs off the ground. The motion of a horse was a debated subject at that time. Today high-speed cameras can be used to study events like this. But, if the target of study is the interior of a material, or if the experiment is surrounded by smoke, fire or debris, then X-rays are needed to detect and “see” the event.
Scandiflash produces flash X-ray instrumentation for a variety of applications across several energy ranges to penetrate everything from smoke to several centimeters of steel. The image at the top of this page shows a projectile hitting a target at 850 meters per second.
Broad band spectrum of Bremsstrahlung
Scandiflash Flash X-ray instrumentation delivers a broad band spectrum of Bremsstrahlung ranging from 20 keV (using an Aluminum X-ray window) or 6 keV (using a soft X-Ray window) to the instrument’s peak voltage (pV). The standard anode material is Tungsten, which produces characteristic radiation peaks at 58 and 67 keV.
As a rule of thumb, the average energy is typically around 1/3 of the maximum energy. An X-ray instrument with a peak energy of 150 keV can penetrate about 3 mm of steel, and with 450 keV, you can penetrate about 34 mm.
Nanosecond pulses
Scandiflash systems generate flash X-Ray pulses in the order of nanoseconds (ns). Each pulse is generated by one channel that contains control electronics, pulser, and X-Ray tube/tubes. Up to 8 consecutive pulses can be generated with one system.
Above: Oscilloscope measurement of a Scandiflash 450 system pulse width showing a pulse full width half maximum of 18.76 ns. Grid line distance in x is 20 ns and y is 2V.
Seeing what the eye can’t see
Visual prerequisites are not limiting factors when using X-rays, as you can see through fire, dust and even solid materials.
Researching dynamics?
Sometimes you only get one chance – make it count.About Scandiflash
For over 50 years, Scandiflash has been pioneering flash X-ray technology to help scientists and researchers around the globe to see the nearly impossible. Scandiflash Flash X-Ray Systems generate extremely short pulses used to capture dynamics in the harshest of conditions, ranging from indoor lab setups to outdoor large-scale firing ranges. The systems are modular and can be tailored to meet your requirements for number of pulses and peak energy conditions.
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