Time-correlated single-photon counting (TCSPC) is a powerful technique to measure fluorescence decays in the time domain. When a substance or matter is irradiated by incident light of a certain wavelength, it absorbs the light energy, enters an excited state, and immediately de-excites in the ground state by the emission of photons. The excited state has a lifetime that depends on a number of ultrafast processes that happen in the molecules. The decay in fluorescence can be measured over a wide time range: from picoseconds to microseconds which makes it a useful technique in bio molecular structure analysis and dynamics. The fluorescence lifetime or the kinetics of de-excitation depends upon several factors such as the chemical composition of its environment, solvation dynamics, or molecular rotation. The lifetime is useful in understanding the processes happening in the excited state. All types (non-hazardous) of liquid and thin-film samples can be characterised using this facility.

Applications

1. Fluorescence lifetime or decay measurements in the time range of nanoseconds to microseconds.

2. Polarisation Anisotropy.

3. Time-Resolved Emission Spectra (TRES).

4. Chemical Science: distance between donor-acceptor, shape, and size of molecules, change in Nano environment, molecular interaction.

5. Biological science/Medical science: protein structure and dynamics, DNA motion.

6. Semiconductor Physics.

7. Industries.