Self Calibration Time Dependent Intensity (TDI) Acquisition
In the self calibration method, the software acquires the on-peak data for the Time Dependent Intensity (TDI) element during the normal sample acquisition process for unknown samples. Time Dependent Intensity (TDI) element fit types (linear and non-linear) may be applied on an element by element basis in the Standard Assignments dialog from the Analyze! window.
Note that this data is also displayed in the Run | Display Time Dependent Intensity (TDI) or Alternating On/Off Intensities menu.
Click the Self Calibration Time Dependent Intensity (TDI) Acquisition option so that the next sample acquisition will be acquired using the self calibration method. The number of count time intervals used is specified in the Time Dependent Intensity (TDI) Count Time Intervals text field. Up to 50 intervals may be used in a Time Dependent Intensity (TDI) acquisition.
For example, if the user enters 5 in the Time Dependent Intensity (TDI) Count Time Intervals text field, and the default on-peak count time is 10 seconds, then the software will automatically count five 2 seconds intervals for the on-peak elements that are first in spectrometer order. Off-peak acquisitions are not affected.
Note that one can significantly reduce the time delay between when then beam is first unblanked and the x-ray counting is started by using the “Synchronous” option in the Acquisitions Option dialog.
To view the Time Dependent Intensity (TDI) calibration data, click the Standard Assignments button in the Analyze! window and select the element to view. Click the Display Time Dependent Intensity (TDI) Fit to view the data for all lines in the sample. Note that the Time Dependent Intensity (TDI) calibration caption will indicate a self calibration correction. That is, the unknown number used for the calibration is itself.