Fig. 1. Experimental setup of BGSe OPO

Fig. 2. The idler laser output energy under the L-shaped cavity

Fig. 3. (a) Parametric light waveforms in BGSe-L cavity (without LBO) with a pump energy of 30 mJ; (b) Parametric light waveforms in BGSe-L cavity (with LBO) with a pump energy of 30 mJ; (c) Parametric light waveforms in BGSe-L cavity (without LBO) with a pump energy of 50 mJ; (d) Parametric light waveforms in BGSe-L cavity (with LBO) with a pump energy of 50 mJ; (e) Parametric light waveforms in BGSe-L cavity (without LBO) with a pump energy of 80 mJ; (f) Parametric light waveforms in BGSe-L cavity (with LBO) with a pump energy of 80 mJ

Fig. 4. Temporal profile of the idler in BGSe-L cavity at a 78 mJ pump energy: (a) with LBO; (b) without LBO

Fig. 5. (a) The relationship between the output wavelength and θ angle of BGSe; (b) The relationship between the output wavelength and φ angle of BGSe （56.3, 0）