Patent ID: 6690463
Filing Date: 2004-02-10
Classification: G01J,G01N

Abstract:
A method for characterizing samples having fluorescent particles, comprising the steps of:exciting particles in a measurement volume to emit fluorescence by a series of excitation pulses, monitoring the emitted fluorescence by detecting sequences of photon counts using a detection means, determining numbers of photon counts in counting time intervals of given width, determining in said counting time intervals detection delay times of the photon counts relative to the corresponding excitation pulses, determining a function of said detection delay times, determining a probability function of at least two arguments, {circumflex over (P)}(n, t, . . . ) wherein at least one argument is the number of photon counts and another argument is said function of detection delay times, and determining from said probability function {circumflex over (P)}(n, t, . . . ) a distribution of particles as a function of at least two arguments, wherein one argument is a specific brightness of the particles, or a measure thereof, and another argument is a fluorescence lifetime of the particles, or a measure thereof.