Photon-counting Spectroscopy
The low noise of CCDs (4-10 electrons rms), and high stopping
power over the 0.3-10 keV range, makes the CCD the ideal photon
counting detector for X-ray spectroscopy applications, such as
EDX and XRF.
An example spectrum obtained from this spectroscopy system is
shown below. This was taken in an XRF application with Pb/Sn solder
as the target. The spectrum (image name) shows the L-emission lines
of Pb and Sn, plus other elemental constituents in the measurement
system like Cu and Al.
Key features of the CCD X-ray spectrometer are:
- Cryogen-free operation using a thermoelectric cooler
- Typical Operating Temperature of -35°C, depending
on requirement
- Resolution of 140 eV at Mn-K (5898 eV)
- Active area of 1-6 cm2 (ideal for low flux applications)
- Count rate 20000/s
- High detection efficiency over 0.5-10 keV band
- Full software control of your system including, readout parameters,
binning and windowing modes
Model |
Pixels |
Pixel Size |
Energy Range (keV) |
XPS 22 |
600x600 |
40.0 |
0.1-20 |
XPS 62 |
385x578 |
22.0 |
0.5-10 |
Images
The CaF spectrum is of a powder sample having 3% CaF component plus an Fe-55
spectrum. Under the photon counting spectroscopy, the KEY result with this
technology is that it provides a spectrum, whilst providing an IMAGE at the
same time.
Three images acquired simultaneously using the multispectral imaging
method at 3.3, 1.7 and 5.0kev from (upper left-to-right respectively)
and (lower) a projected density distribution obtained by phase
retrieval from these images. This image was taken by CSIRO with equipment supplied
by XCAM, and was published in the Journal of Microscopy, vol. 207,
pt. 2, August 2002, page 93, and published with Blackwell's permission. Further information about this application, using Xcam hardware for X-ray projection microscopy, can be found on the 'Application Notes' page of this website.
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