Figure 11.

Overall illumination with LEDs tilting for $s_i=1\forall i$, ${\mathrm{\Phi }}_{1/2}={20}^0$, $\rho ={30}^0$. (a) $\rho ={30}^0$, $\epsilon =0^0$. (b) $\rho ={30}^0$, $\epsilon ={90}^0$. (c) $\rho ={30}^0$, $\epsilon ={180}^0$. (d) $\rho ={30}^0$, $\epsilon ={270}^0$.