Method for estimating fluorescent species in a fluorescent sample capable of emitting a fluorescent signal, wherein said fluorescent signal can be represented through phasors, comprising the following steps: a. generating a semi circumference, associable to said fluorescent signal emitted by said fluorescent sample, on a Cartesian plane of coordinates (g, s) in the phasor space; b. defining a maximum number of primary components in which said fluorescent signal is to be divided; c. defining, for a first number of components N=2 and for the first harmonic H=1, a plurality of points of coordinates (g, s) on said semi circumference; d. for each of said components, generating a plurality of possible polygons whose vertices coincide with a number of points of said plurality of points equal to the number of components defined in said step c.; e. calculating the coordinates (g',s') of the barycenter (B P) of each polygon of said plurality of possible polygons; f. saving the vertices and the barycenters (B P) of all polygons of said plurality of possible polygons generated in said step d.; g. repeating said steps d. -f., for each harmonic following said first harmonic H = 1; h. repeating said step g., for each number of components following said first number of components N=2; i. acquiring said fluorescent signal; j. defining the number of components in which said fluorescent signal is to be divided; k. calculating the barycenter of said fluorescent signal in coordinates (g, s); l. selecting the polygon of said plurality of polygons whose barycenter (B P) is at the minimum distance from said barycenter calculated in said step k.; m. calculating the lifetimes (τ) of the primary components from the coordinates (g, s) of the vertices of said polygon selected in said step 1.; n. sending the values of the lifetimes (τ), calculated in said step m., to said interface. a. generating a semi circumference, associable to said fluorescent signal emitted by said fluorescent sample, on a Cartesian plane of coordinates (g, s) in the phasor space; b. defining a maximum number of primary components in which said fluorescent signal is to be divided; c. defining, for a first number of components N=2 and for the first harmonic H=1, a plurality of points of coordinates (g, s) on said semi circumference; d. for each of said components, generating a plurality of possible polygons whose vertices coincide with a number of points of said plurality of points equal to the number of components defined in said step c.; e. calculating the coordinates (g',s') of the barycenter (B P) of each polygon of said plurality of possible polygons; f. saving the vertices and the barycenters (B P) of all polygons of said plurality of possible polygons generated in said step d.; g. repeating said steps d. -f., for each harmonic following said first harmonic H = 1; h. repeating said step g., for each number of components following said first number of components N=2; i. acquiring said fluorescent signal; j. defining the number of components in which said fluorescent signal is to be divided; k. calculating the barycenter of said fluorescent signal in coordinates (g, s); l. selecting the polygon of said plurality of polygons whose barycenter (B P) is at the minimum distance from said barycenter calculated in said step k.; m. calculating the lifetimes (τ) of the primary components from the coordinates (g, s) of the vertices of said polygon selected in said step 1.; n. sending the values of the lifetimes (τ), calculated in said step m., to said interface.