RESUMO
The present paper reports theoretical and experimental research on the tunable output characteristics of periodically polarized lithium niobate. We made six equal distance crystal grating sections, with each distance being 0.5 mm and the polarization period range of 29.0-31.5 mm. Especially, at room temperature, the signal-wavelength tunable output in the range of 1 449.7-1 665.0 nm and idle-wavelength tunable output in the range of 3 989.2-2 946.0 nm were achieved by LD end-pumped Nd : YVO4 laser with Q-switch in sound-wave. The lowest excitation threshold was 108.0 mW, while the highest excitation threshold was 149.2 mW. When the pump power was 649 mW, the highest gained signal-wave output was 118.5 mW and its conversion efficiency was 18.26%. Meanwhile, the idle-wave output was 46.6 mW and its conversion efficiency was 7.18%. These parameters approached the practicality level.