Search

In this study, efficient third harmonic generation was investigated by employing a delay line and LiB 3 O 5 (LBO) crystals with 600 fs pulse lasers at 1030 nm. We systematically investigated the differences in the frequency conversion of the LBO crystals for second and third harmonic generation with varying beam spots. Specifically, it has been demonstrated that the inclusion of a delay line is necessary to mitigate the group velocity mismatch at hundreds femtosecond laser. The results indicate that the maximum output powers are approximately 16.5 W and 5.6 W at wavelengths of 515 nm and 343 nm, respectively. The corresponding optimal conversion efficiencies are 59.6 % (from 1030 nm to 515 nm) and 20.4 % (from 1030 nm to 343 nm). And the beam quality has improved noticeably at 515 nm (M x 2 = 1.16, M y 2 = 1.13) and 343 nm (M x 2 = 1.16, M y 2 = 1.12), in contrast to that at 1030 nm (M x 2 = 1.56, M y 2 = 1.49). • High efficiency and high beam quality THG by employing LBO crystals is obtained. • The effectiveness of a delay line for THG of hundreds femtosecond laser is demonstrated. • Different focusing lenses on LBO crystals to stimulate SHG and THG are discussed. • The effects of different types of LBO crystals for THG are investigated. [ABSTRACT FROM AUTHOR]

We demonstrate an acousto-optic Q-switched LED-pumped laser with high repetition rate and beam quality with a compact linear cavity. By optimizing design of the LED-pumped Nd:YAG rod laser, a maximum average power of 2.5 W at 1063.92 nm laser with duration of 1.34 μs is achieved, corresponding to an optical efficiency of 8% and a slope efficiency of 10.7%. After optimizing the resonator configuration with an acousto-optic Q-switched modulation, a 1.2 W average output power of pulsed laser with duration of 296 ns is obtained with a peak power of 810 W at a repetition rate of 5 KHz. The beam quality factors of M x 2 = 2.12 and M y 2 = 1.77 are obtained through mode selection by pinhole. To the best of our ability, this is the best high repetition rate and beam quality of an acousto-optic Q-switched LED pumped laser oscillator with watt-level output reported so far, which means that LED pumped solid-state lasers will make breakthroughs in various scientific and technological applications. • First demonstration of a LED-side-pumped acousto-optic Q-switched Nd:YAG rod laser with high repetition rate and beam quality operation. • Realize Watt-level actively Q-switched laser with LED-pumped Nd:YAG module for the first time. • Explore the new technical scheme to realize more efficient LED-pumped Nd:YAG module. [ABSTRACT FROM AUTHOR]