Fig. 1.

QD655 are better excited by an OPO. (A). QD655 two-photon excitation spectrum under a NLO (green, 720-1040nm) and an OPO (red, 1050-1300nm) excitation. Signal was collected on the 5 NDDs and spectrum was normalized to laser power. Inset: laser power at the output of the objective. (B). Cluster of QD655 imaged under an 800nm NLO (top) or 1050nm OPO (bottom) excitation. Signal was collected on the 605-678 NDD (NDD1). Scale-bars: 25µm. (C). Emission intensity of QD655 coated on a glass coverslip and excited by an 800nm NLO (green) or 1050nm OPO (red) excitation. Emission was normalized at 100 for NLO excitation. *: p = 0.0003, Wilcoxon signed rank test.