FIGURE 2.

Evaluation of the signal/noise ratio of a single colloidal particle. The solid line represents the bleaching curve of a single 210-nm particle imaged 40 consecutive times and fitted to an exponential decay. Fluctuations in the integrated intensity are calculated as the standard deviation (δ_I) of each point from the fit. This yielded a deviation value of δ_I = 5.1%. The dashed line indicates the mean integrated intensity of the full population imaged 40 consecutive times and fitted to an exponential decay. This yielded a deviation value of δ_I = 2.8%. (Inset) Intensity histogram of the full population constructed from the first micrograph in the time series.