Highly Efficient Generation of 486.1-nm Blue Laser for Dual-Wavelength Oceanic Lidar Transmitter

A blue-green dual-wavelength oceanic lidar transmitter prototype based on a frequency-doubled potassium titanyl phosphate optical parametric oscillator was demonstrated and the optimization of conversion efficiency was analyzed. Pumped by a 532.2 nm pulsed laser with a pulse energy of 33 mJ, the maximum output energy of 9.63 mJ signal laser pulse at 972.2 nm was successfully obtained, corresponding to a high optical-to-optical conversion efficiency of 29.1%. The blue laser at 486.1 nm was generated through second harmonic generation process using a lithium triborate crystal, and the maximum single pulse energy and pulse width were 1.38 mJ and 4.18 ns. This blue-green dual-wavelength pulsed laser has been integrated into an oceanic lidar system and deployed in the East China Sea.