Eye-safe actively Q-switched diode-pumped lasers with intracavity Raman conversion in YVO4, KGd(WO4)2, PbWO4, and Ba(NO3)2 crystals

Abstract We have investigated the self-Raman and intracavity Raman frequency conversion of the end-diode-pumped acoustooptic Q-switched Nd:YVO 4 laser radiation to eye-safe radiation. The 1st Stokes oscillation in YVO 4 (Nd:YVO 4 ), KGd(WO 4 ) 2 , PbWO 4 , and Ba(NO 3 ) 2 crystals excited by the laser radiation at a wavelength of 1342 nm permits obtaining oscillations at 1524, 1496 or 1527, 1527, and 1562 nm wavelengths, respectively. We have obtained pulsed lasing with a repetition rate of 2–20 kHz, an output energy of 37–95 µJ, and a duration of 6–8 ns. We propose a model of the actively Q-switched intracavity Raman laser taking into account the real switching off/on times of the actively Q-switch and the excited state absorption in the active medium. We used this model to simulate the dynamics of the self-Raman Nd:YVO 4 laser. The proposed model gives results that agree fairly well with the experimental data.