Fig. 1. Structure of plane-parallel cavity based KTP-OPO

Fig. 2. Pulse envelops of KTP-OPO input pump(dashed),output idler(solid)and depleted pump(dotted),where the inset exhibits OPO output beam profile

Fig. 3. OPO output versus cavity mirror misalignment angle in different directions

Fig. 4. SchematicofKTPprincipaldielectricaxesand crystallographic orientation

Fig. 5. Dependenceof alignment toleranceonpumpbeam diameter and output energy.(a)Dependence of alignment tolerance on pump beam diameter;(b)dependence of alignment tolerance on output energy

Fig. 6. Alignment tolerance as functions of cavity length at given input and output energies.(a)At given input energy;(b)at given output energy

Fig. 7. Input-output relationship of KTP-OPO with different cavity lengths

Fig. 8. Variation of output beam divergent angles in horizontal andverticaldirectionsandroot-mean-square(RMS)pulse energy fluctuation with cavity length