Tracking error compensation capacity measurement of a dual-rod side-pumping solar laser

Abstract

We present here the first experimental results of tracking error compensation capacity of a solar-pumped laser, with a largely enhanced tracking error tolerance achieved by pumping two laser rods simultaneously. A large aspherical fused silica lens, with an input face of 46 mm radius of curvature and 84 mm diameter, provided an efficient focusing of the concentrated solar radiation from the focal spot of the parabolic mirror onto the two laser rods, mounted within two semicylindrical pump cavities. A large improvement in tracking error compensation capacity was experimentally obtained, leading to an enhancement in tracking error width at 10% laser power loss (TEW10%) of 14.0 and 6.0 times in its vertical and horizontal setups, respectively, as compared to previous results by numerically simulated single-rod scheme. Regarding the numerical dual-rod scheme, an improvement of 3.5 and 1.5 times in the vertical and the horizontal setups, respectively, was also obtained by the present scheme. In comparison to the previous dual-rod scheme using a semicylindrical lens and a CPC pump cavity, the TEW10% was enhanced by 3.9 and 1.7 times, respectively, with the vertical and the horizontal setups.