Highly efficient side-pumped solar laser

The power density of solar on the earth is so low that it can't achieve to pump laser. To surpass the lasing threshold, the solar has to be highly concentrated. We propose the highly efficient concentration system, which is composed by a Fresnel lens and a three-dimensional compound parabolic concentrator (3-DCPC). With the help of 3-DCPC, we increase the concentration ratio which is applied to the laser crystal. The exit of the 3-DCPC is placed in one focus of an elliptical chamber, so the solar is coupled into the elliptical chamber, pumping Nd:YAG laser media. Laser output of 6.2 W has been achieved, and the collect efficiency is 6.2W/m
²
in the experiment.