Research On440Nm Passively Q-switched All-solid-state Laser

440nm laser has a wide applications in biological, medical, laser display and marine exploration. In this thesis we use LD end-pumped Nd:YAG and V:YAG crystal as passive Q-switch to produce1319nm pulse laser. Frequency doubling of1319nm with I phase matching LBO to obtain660nm.440nm laser is achieved by1319nm and660nm sum-frequency with II phase matching LBO.Discuss the analytical solution of the passively Q-switch rate equation. Combine with the three-wave coupled equations to discuss the impact of frequency conversion efficiency. Design cavity length by the transfer matrix of the Gaussian beam in the resonant cavity. Simulate the best match angle by the dispersion equation and phase matching type of LBO crystal.Set up experimental of1319nm fundamental frequency to study the peak power and wavelength, When the1319nm power is335mW to obtain the440nm average power of8.39mW, the conversion efficiency is2.5%,4h power stability of0.638%. The method in this thesis is the first time to achieve440nm in the currently reported, so the research of thesis has important implications.