TESTING & MEASUREMENT
XRF Analysis with Proportional Counter ( PC ) Tube
The crucial component for the method of XRF analysis is the detector , which detects the fluorescence radiation and measures it with the highest accuracy . The information from the detector is passed to the analysis software and processed accordingly . The detector type determines which measurement tasks you can solve with the XRF spectrometer . We offer the most comprehensive detector portfolio on the market . This means that only at Fischer will you find the detector tailored to your measurement task and solve it optimally .
The well-tried proportional counter ( PC ) tube is indispensable in the portfolio of a measurement technology specialist . It offers a vast active detector area with a slightly curved window . This feature allows achieving high count rates as a large amount of fluorescence radiation reaches the detector . It makes measurements at 20 – 80 mm away from a sample possible . The PC tube is predestined for coating thickness measurements in the range of 1 – 30 µ m and small measuring spots . Another advantage is that the PC tube is significantly less sensitive regarding the accuracy of the sample alignment to the detector and the measuring distance setting . The PC tube features the drift compensation developed by Fischer as standard , which gives exceptional stability .
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Let ’ s explore the advantages :
The detector takes on a crucial function in X-ray fluorescence ( XRF ) analysis . A detector can detect if the atoms in the sample to be measured are excited by an X-ray beam to emit fluorescence radiation . The measurement software then evaluates the detected radiation . Only at Fischer users can choose from the three most crucial detector types . In addition to the silicon PIN diode ( Si-PIN diode ) and the silicon drift detector ( SDD ), the proportional counter tube is indispensable in the portfolio of a measurement technology specialist as an inexpensive yet powerful alternative .
Since the early 1980s , XRF measurement technology has been used to measure the thickness of metallic coatings . Today , XRF is firmly established in the everyday industry and the laboratory . The thinnest layers on connectors , printed circuit boards , fasteners , and much more can be measured quickly , precisely , reliably and non-destructively . A detector is necessary to determine the fluorescence radiation generated by the layers ’ excitation by X-rays . The information from the detector is passed to the evaluation software and converted into the corresponding layer thickness .
The first detector on the market was the proportional counter tube . This is a counter tube filled with gas . The fluorescence radiation is detected by passing through the window and interacting with the gas . Over time , other types of detectors were added : the Si-PIN diode and the SDD . These have a higher energy resolution , which is why they are
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