The idea of the time stamp concept is, to mark every event with a unique number, specifying the time range of the appearance of the event. This time range can be the period between to adjacent laser- or synchrotron-light-pulses or any other time range defining a unique marker for your events. We call this marker the time stamp. In a laser experiment you can e.g. use the laser pulse as a trigger for an external counter. If you store the counter numbers of all events together with the time-of-flight data you can select coincident events by their counter numbers after the measurement has been performed. Thus, you don't have to set any hardware gates to restrict your data flow to a certain class of coincidences but you just scan your data for time stamps fulfilling the coincidence restrictions you define via software.
Our Time to Digital Converters (TDCs) are supplied with a 32bit parallel data input which can be used to include an external time stamp in the data flow. The combination of one of our TDCs with our time stamp module provides you with 4 independent coincident measuring channels. This means, just by supplying one time stamp you cover all coincidence measuring possibilities between the 4 channels which are 6 different double coincidences, 4 different triple coincidences and 1 fourfold coincidence. With every additional TDC you increase the number of coincident measuring channels by 4 including a very rapidly growing number of coincidence measuring possibilities, while your expenses increase at most linearly with the number of TDC units.
The TDC cards can also read in and add a time stamp to the data of our Position Sensitive Detector, so you can use it in coincidence with other spectrometers or combine several position sensitive detectors or...