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with SPAD powered vTAU camera
The complete high-speed recording solution
High-speed camera for fluorescence imaging
Intensified high-speed camera
Intensified camera with ultra-short gating
High-speed Intensified Camera Attachment
Compact lens-coupled image intensifier
Intensifier Control
Unit for Automated Systems
Record and edit high-speed videos with one or multiple cameras.
Record and analyze fluorescence lifetime images.
Custom imaging products, sensors and software for low light level applications.

Why does the phase lifetime differ from the modulation lifetime?

The lifetime from phase and modulation are the same only if all the fluorophores behave according to a single exponential decay. In this case we speak of a mono-exponential fluorescence lifetime distribution and the lifetime calculated from the phase shift and the lifetime calculated from the modulation depth are in this case identical. In case of multi-exponential lifetime distributions, the lifetimes calculated from the phase shift and from modulation depth will be different because the equations on which the lifetimes are based assume mono-exponentiality. The more exponents the more both lifetimes differ. For FRET or for tracking lifetime changes the lifetime from phase can be taken to determine the changes in lifetimes.

For multi-exponential distributions, a multi-frequency recording can be used and the phase and modulation behaviour can be fitted with a multi-exponential model, in a similar way as in time domain FLIM (TCSPC). This allows one to retrieve multiple lifetime components and their relative fractions.