Teledyne PIXIS-XF, System Manual

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Chapter 1: Introduction
1.1 When Flexibility Counts
Teledyne Princeton Instruments knows that a camera designed to detect X-ray photons
for scientific research needs to be flexible. X-ray scattering from complex crystals such
as proteins requires high dynamic range and low-noise readout, whereas scattering
from materials like polymers, fibers, and powders requires deep cooling and rapid
imaging to capture phase or morphological changes during thermal or mechanical
processing. Shutterless operation, low noise, and the ability to select a fiber ratio up to
3:1 make the Teledyne Princeton Instruments’ PIXIS-XF system an ideal choice for both
of these applications.
In fact, PIXIS-XF high-performance systems are designed specifically for applications
like X-ray tomography, X-ray topography, medical X-ray imaging, nondestructive
testing (NDT), streak tube readout, and image intensifier readout.
When a 1:1 fiberoptic-coupling configuration is chosen, these cameras are well suited
for streak tube and image intensifier readout or low X-ray flux imaging.
1.2 Fiberoptic Expertise
The PIXIS-XF camera system utilizes Teledyne Princeton Instruments' fiberoptic
coupling technology to ensure the highest possible resolution. This process eliminates
any intermediate fiberoptic faceplate or unreliable oil layer between surfaces. An
optional phosphor screen (GdOS:Tb) that absorbs X-rays and emits visible light
(~550 nm) can also be coupled to the CCD with a fiberoptic in order to detect X-rays.
When the highest sensitivity is required, such as when detecting low flux or lower X-ray
energies (~5 keV), smaller taper ratios and back-illuminated CCDs are offered. For
distortion-free imaging, a 1:1 fiberoptic system is recommended, while for maximum
field of view – ideal for high-brilliance sources like third-generation synchrotrons –
tapers with diameters as large as 165 mm (with other high resolution CCDs) are
recommended. Contact the factory for further information.
1.3 Shuttering and Synchronization
Electrical timing signals are available from the back panel of the camera for
synchronization with a customer-provided X-ray shutter. The CCD can be continuously
cleared of dark charge while waiting for an exposure to begin. Exposures that are much
longer than the CCD readout time can be performed without a shutter, as the amount
of smearing (due to continued exposure during readout) will be low.
1.4 Low-Noise Configurations
The PIXIS-XF system provides either a forced-air or liquid-cooling option to reduce
dark current. The thermoelectric (Peltier) design and precision electronics provide very
high precision as well as the capability to set the required temperature.
For flexibility, the fiberoptic extends outside the vacuum, allowing you to change
scintillators/phosphors for specific X-ray energy without breaking vacuum or coupling
the camera system to streak tubes or image intensifiers.