Hi,
In excited state lifetime measurement with TCSPC instrument theoretically it is assumed that lifetime down to ~1/10 th of the IRF FWHM to be recovered by iterative reconvolution technique. I want to know how this 1/10 factor is coming? Can anyone give me any references/journals of the derivation from where this 1/10 number is obtained? (please do not suggest me the user guide or manuals, I want references of some journals or books).
Thanks
Hello. The 1/10 is just a guess typical for 10.000 counts in the max. It depends strongly on the signal quality. Lakowicz (principles of fluorescence spectroscopy) uses so called F-statistics to judge for resolution limits of TCSPC.
Some years ago I made some simulations and experiments showing that in principal you can become far better if there is no signal distortion (but you always have! - So at best you would quantify your distortions and monitor them via the IRF) and if you make long term measurements collecting much more than 10.000 counts in the max - you might resolve also a 1 ps component with 100 ps IRF.
Conference Paper Resolution Limits Of Time And Space Correlated Single Photon...
The 1/10th width of IRF as a rule of thumb is proposed by M.A. West ("Photochemistry", vol.10, p.40, Chem. Soc., 1979, London), among others, but different numbers and derivations can be found in the literature. A fairly detailed overview with references is given in the book "Time-correlated single photon counting" (O'Connor, Phillips, Academic Press, 1984, London).
As Franz-Josef Schmitt explained, the maximal time resolution varies with many factors, including the number of counts, the shape of the IRF, how many fluorescence decay lifetimes are present and how they are distributed, and so on. It is not difficult to simulate all this theoretically and calculate your uncertainty in resolving a decay component of interest.
- Badges
- Science topic