We report a high power continuous tunable blue light generation by frequency doubling of signal wave from a nanosecond 532-nm-pumped optical parametric oscillator (OPO) in LiB 3 O 5 (LBO). The nonlinear crystal BiB 3 O 6 (BiBO) is used for the second harmonic generation (SHG). Three BiBO crystals have been arranged for the walkoff compensation SHG. The large blue tuning range from 450 to 495 nm with average output powers around 1 W have been achieved. The maximum output power is up to 1.3 W at 470 nm.An all-solid-state laser source in the blue spectral region is attractive for its potential applications in high-density optical storage, photolithography, laser display, laser printing, Raman spectroscopy and undersea communications. Most works have been concentrated on frequency doubling of the diode-pumped quasi-three-level Nd 3+ laser such as Nd:YAG, Nd:YVO 4 , and so on. 1,2 For example, C.Czeranowsky et al achieved 2.8 W output at 473 nm by intracavity frequency doubling of Nd:YAG laser. 3 However, these lasers have a fixed wavelength, which puts a limitation to their applications, especially in those fields needing wavelength tuning.A promising alternative method for high power tunable blue generation is second harmonic generation (SHG) of an output from an optical parametric oscillator (OPO), which has the advantages of powerful, tunable and reliable.However, the SHG conversion efficiency or the output power is often limited by the birefringent walkoff. Therefore, SHG walkoff compensation 4 provides an ideal way to overcome the problem.In this letter we present a compact, high power, widely tunable blue laser of signal light from a 532-nm-pumped OPO with nonlinear crystal LiB 3 O 5 (LBO). The experimental arrangement for a blue generation is shown in Fig. 1. This system consists of a single-resonant OPO and a frequency doubler for the signal wave. The OPO is pumped by a 1 Corresponding author Email: xcLin@red.semi.ac.cn, Xuechun Lin, graduating from Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences with a Doctor of Science degree, engaged in optical parametric oscillators and all solid state lasers. Address: Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/15/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspxhome-made solid-state green laser at 532 nm, which is the frequency doubling of a diode-pumped 1064 nm Nd:YAG laser with a repetition rate of 10 kHz and a pulse width of 60 ns. Details of the green laser have been described in an earlier publication. 5 Three BiB 3 O 5 (BiBO) crystals were arranged for SHG walkoff compensation as shown in Fig. 2, with blue average powers around 1 W. The wavelengths ranging from 450 to 495 nm have been achieved by changing the temperature of the LBO crystal in the OPO cavity and adjusting the direction of the BiBO crystals simultaneously. The maximum power of 1.3 W was measured at 470 nm.The green beam is passed through an optical isolator and is focused into the OPO cavity, which is composed of an input mirro...
