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Fig. 16.3:
Percentage of change in the detected energy when exactly one pulse is left out, in correlation with the pulse
frequency
Tab. 16.1 shows the number of detected pulses during the maximum integration time and during an integra-
tion time of 1 ms for different pulse frequencies. Quantization with low pulse frequencies is clearly illustrated
in the column for the maximum integration time. While 2 250 pulses are detected at a pulse frequency of
10 kHz, at 10 Hz there is only one or no more than two.
If the signal level is too high during a measurement at 10 Hz pulse frequency and the software tries to adjust
the integration time, there are only three possible results. The energy application for a measurement remains
the same, it decreases by 50 %, or it drops to zero. These increments are less significant at a pulse frequen-
cy of 10 kHz. This correlation is shown in general terms in Fig. 16.3 on page 112. It can be seen that from a
pulse frequency of 500 Hz, the minimum jump with a reduction of the integration time is 1 %.
Small pulse frequencies aren't the only thing that will cause quantization though. If the pulse energy is very
high and it isn't possible to further increase the attenuation, the integration times will be smaller. In Tab. 16.1,
an integration time of 1 ms is added to the maximum integration time. In this case, a pulse frequency of
500 Hz is not sufficient in order to quasi continuously control the energy application for each measurement
through integration time control.
A total of four states can always be differentiated on the way from low to high pulse frequencies or from short
to long integration times. This is demonstrated by the following example for measuring pulsed irradiation
during quasi-cw operation.
112
Pulse frequency in Hz
MSM+ HB
Revision 00 EN - 02/2022
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