  We compare calculations based on the Dynamical Mean-Field Theory of the
Hubbard model with the infrared spectral weight $W(\Omega,T)$ of
La$_{2-x}$Sr$_x$CuO$_4$ and other cuprates. Without using fitting parameters we
show that most of the anomalies found in $W(\Omega,T)$ with respect to normal
metals, including the existence of two different energy scales for the doping-
and the $T$-dependence of $W(\Omega,T)$, can be ascribed to strong correlation
effects.
