High Efficiency Generation Of447Nm Radiation By LD End-pumped Nd:YVO₄

LD end-pumped Nd:YVO4efficient447nm blue lasers in the military field, the field of communication has important applications. In this paper, the nonlinear frequency conversion technology, design a LD end-pumped Nd:YVO4high efficiency447nm blue lasers.Based on the nonlinear frequency conversion theory, the phase matching angle and frequency doubling crystal crystal, the effective nonlinear coefficient, walk-off angle, allowing the angle of the main parameters. Comparative analysis of the nonlinear crystal to select the best frequency conversion crystals. Simulate the different parameters on the fundamental optical frequency conversion efficiency and impact. To improve the conversion efficiency, external cavity design and frequency crystal cascade structure, the structure of the series and the impact of the conversion efficiency of the polarization state of the theoretical analysis. According to the analysis results to design LD end-pumped Nd:YVO4laser as acousto-optic Q baseband source. Crystal parameters, cavity structure, the output mirror transmittance, Q-parameters were simulated theoretical calculations. Build LD end-pumped Nd: YV04acousto-optic Q baseband device, using cavity LBO doubling output671nm red light, after the use of an external cavity focus LBO/KTP and frequency experiments conducted.Repetition frequency is10kHz, the maximum average power obtained was2.8W. Optical conversion efficiency of12.8%. The shortest pulse width of31ns. External-cavity frequency doubling the maximum output power of red140mW, the fundamental frequency light to red light conversion efficiency of4.6%. Pulse width70ns. Cavity frequency doubling the maximum output power of red210mW. Red light to baseband conversion efficiency was7.8%. Corresponding to the pulse width is107ns. One KTP crystal conditions, access to32mW blue output from baseband blue light to optical conversion efficiency of1.5%. Double KTP crystals obtained under conditions of blue40mW output from the baseband blue light to optical conversion efficiency of1.9%.