A new data acquisition software is now available for the PicoHarp 300 Time-Correlated Single Photon Counting system from PicoQuant. The new version 2.3 provides a new real-time correlator for fluorescence correlation spectroscopy that calculates two autocorrelations and the cross correlation between two photon streams simultaneously, making best use of current multiprocessor systems. The new release also provides better support for online help under Windows Vista. It furthermore supports control for additional monochromator models, permitting the automated recording of Time-Resolved Emission Spectra (TRES).
The PicoHarp is based on an entirely new time digitiser with 4ps resolution, a very short dead time, a processing rate of up to 10 million counts per second, and an extremely low differential non-linearity. It provides unique new features, notably two identical input channels that can operate independently, but with a common crystal time base. Therefore, not only classical TCSPC histograms for the measurement of fluorescence decays, but also picosecond coincidence correlations can be obtained. This is implemented using the instrument's Time-Tagged Time-Resolved (TTTR) mode, which records the picosecond arrival time of each individual photon. As a further improvement over the previous versions the new software now also supports correlations in the instrument's most advanced time tagging mode where both inputs are used as detector channels.