Evolution of the observed light curve as a function of the radius of emission. Top panel: Synthetic synchrotron and inverse Compton (isotropic radiation field) light curves as a function of the emitting radius, from the light-cylinder radius up to 5_LC for the dipole simulation (χ = 60°, α = 90°). Bottom panel: Full width at half maximum of the inverse Compton pulse width as a function of radius for the dipole (magenta crosses) and split-monopole (blue dots) simulations. The red dotted and dashed lines shows the two asymptotic behaviors discussed here. The black vertical dashed line marks the location of the critical radius r_m where the emitted pulses are the narrowest.