All simulations were performed at an obstacle density of C=0.39 (inert obstacles). Either no illumination (till = 0; open circles) or continuous illumination (till = tdelay; cross) was simulated. (A, B) show the ratios of diffusion constants DON/Dfree, (C, D) the ratios DON/DOFF. In (A) and (C), mobility was calculated according to D = msd/(4tlag), in (B) and (D) according to D = Δmsd/(4Δtlag), where Δmsd = msd(tlag) – msd1.