Abstract
We report the generation of tunable femtosecond pulses from 380nm to 465nm near the degenerate point of a 405-nm pumped type-IBBO noncollinearly phase-matched optical parametric amplifier (NOPA). The tunable UV/blue radiation is obtained from sum frequency generation (SFG) between the OP A output and the residual fundamental beam at 810-nm and cascaded second harmonic generation (SHG) of OP A. With a fixed seeding angle, the generated SFG and SHG covers from 385 nm to 465-nm. With a pumping energy of 75 μJ at 405 nm, the optical conversion efficiency from the pump to the tunable SFG is more than 5% and the efficiency of SHG of the OP A is about 2%. © 2003 Optical Society of America.