FIGURE 3.

Semilogarithmic representation of the fluorescence intensity (normalized to 1 at t = 0) as a function of time for various compartment radii: R = 10 μm (solid line), R = 20 μm (dashed line), and R = 30 μm (dotted line), with a given diffusion constant, D = 30 μm²/s and bleaching frequency, K₀ = 1 kHz. We observe the fast decay at short times controlled by the competition between the photobleaching and the diffusion. The inset shows the decay at very short times, which is independent of the compartment size. The thin line corresponds to the exponential fit in the neighborhood of t = 0.