简介:Aweakinfrared(IR)imageamplifierwithmorethan60-dBopticalgainandfrequencyup-conversionisdevelopedfromapicosecond(PS)355-nmpumpedgatedopticalparametricamplifier(OPA)inaβ-BaB2O4(BBO)crystal.TheIRimageat1064nmisamplifiedandup-convertedintothevisibleregionat532nmbyparametricamplificationandup-conversion.Withtheoptimizedopticalgain,thelowestdetectableenergyoftheimagecanbeaslowas1.8femto-Jouleperpulse,whichisthreeordersofmagnitudelowerthanthedetectionlimitofacharge-coupleddevice(CCD)camera.ThetransversalresolutionoftheOPAimagingisinvestigated,andtheapproachesforhigherdetectionsensitivityandhighertransversalresolutionareproposed.