Specifications

System Parameters of the DPC-230 43
System Parameters of the DPC-230
The system parameters panel of the DPC-230 is shown in Fig. 70. The panel contains separate
sections for the measurement control parameters and the hardware settings of the CFDs and
the TDCs.
Fig. 70: System parameters of the DPC-230
Operation Mode
The operation mode of the DPC is selected by two parameters. The first parameter determines
the hardware configuration, the second one the way the photon data are interpreted. The selec-
tion panel is shown in Fig. 71.
Fig. 71: Selection of the operation mode
Absolute Time
‘Absolute Time’ is an absolute timing mode. It records the photons of all active channels (see
‘Absolute Timing’, page 2) with their times from the start of the experiment. The way of in-
terpretation is ‘Correlation’. The Absolute Time mode is used to obtain intensity traces, pho-
ton counting histograms, and fluorescence correlation and cross-correlation functions for a
large number of detector channels. Correlation can be obtained over a wide time range from
picoseconds to seconds.
TCSPC FIFO
‘TCSPC FIFO’ records three detector signals and one reference signal via the CFD inputs.
The mode delivers both relative and absolute photon times. The absolute times are referred to
the start of the measurement, the relative times to reference pulses from the light source. The
time measurement is ‘reversed start-stop’, i.e. the times are measured from the photons to the