The collection probability p_c of the classical fluorescent collector geometry (Fig. 1a) fully covered with solar cells at its sides depends on the collector length l normalized to the thickness d. A perfect mirror covers the back side. The systems with a photonic band stop filter (PBS, open symbols) have higher collection probabilities than those without PBS (filled symbols). For the system with PBS a value of p_c close to unity remains up to a normalized collector length l/d ≈ 500 and non-radiative recombination probability p_nr = 0 in the dye. In contrast, the system without PBS has a maximum p_c only slightly above 80% even in the radiative case with p_nr = 0. With increasing collector length l/d the collection probability p_c decreases immediately. The consideration of non-radiative recombination in the dye, i.e. p_nr > 0, leads to a deterioration of p_c in all cases. The cell coverage fraction f (top axis) is directly linked to the collector size for the chosen geometry.