RESUMO
We propose here a novel concept to a large improvement in TEM00-mode side-pumped solar laser collection, conversion efficiencies, and brightness figure of merit by pumping two thin laser rods simultaneously, each rod being pumped by half of the solar collector area instead of today's one thick rod scheme pumped by the full solar collector area. A semicylindrical fused silica lens allows an efficient focusing of the concentrated solar power from the focal zone of the parabolic mirror into the two thin laser rods mounted within two compound parabolic concentrator-semicylindrical pump cavities within the same laser head. 17.2 W continuous-wave TEM00-mode solar laser power was numerically calculated, corresponding to 11.0 W/m2 solar laser collection efficiency, 1.31% incoming solar power-to-TEM00-mode laser power conversion efficiency, and 14.3 W brightness figure of merit, being 1.39, 1.23, and 2.21 times, respectively, higher than the previous state-of-the-art experimental records.
RESUMO
A large aspheric fused silica lens was used to couple efficiently the concentrated solar radiation from the focal zone of a 1.5-m-diameter primary concentrator into a 4-mm-diameter, 35-mm-long Nd:YAG single-crystal rod within a conical pump cavity. Continuous-wave laser power of 29.3 W was measured, attaining 25.0 W/m2 solar laser collection efficiency, corresponding to a 19% increase over the previous record. Its laser beam figure of merit-the ratio between laser power and the product of Mx2, My2 beam quality factors-of 0.01 W is 1.6 times higher than that of a direct tracking solar laser with 30 W/m2 collection efficiency. A strong dependency of solar laser power on laser resonator cavity length was found.
RESUMO
We report a large improvement in the collection and slope efficiency of an Nd:YAG solar laser pumped by a heliostat-parabolic mirror system. A conical fused silica lens was used to further concentrate the solar radiation from the focal zone of a 2 m diameter primary concentrator to a Nd:YAG single-crystal rod within a conical pump cavity, which enabled multipass pumping to the active medium. A 56 W cw laser power was measured, corresponding to 21.1 W/m2 record-high solar laser collection efficiency with the heliostat-parabolic mirror system. 4.9% slope efficiency was calculated, corresponding to 175% enhancement over our previous result.
