530 (550) nm output increases by 30% (20%). Based on Fig. 3 we have calculated the FIR against the R value
[FIR=IH/IS with IH (IS) denoting the 530 (550) nm fluorescence intensity]. The results are shown in Fig. 3 too. We note that the FIR can be thought as unchanged within the error, implying that the KBr itself does not affect the FIR value.