Development of single-resonant optical parametric oscillator with tunable output from 410 nm to 630 nm

A single-resonant low-threshold type-I β-Ba2BO4 (BBO) optical parametric oscillator (OPO) with tunable output from 410 nm to 630 at 5 kHz repetition rate is reported. By taking the noncollinear phase matching method, OPO operation could be obtained compared configuration of collinear matching, and maximum optical–optical conversion efficiency 11.8% was achieved 500 wavelength when 0.4 mJ pump pulse energy applied. When noncollinearity angle preset 1.6°, 4.8°, 6.3°, a continuously tuning total spectral range 220 successfully by adjusting BBO crystal.