Solar laser pumping approach for both simultaneous and stable multibeam operation under tracking error condition

Abstract

.A solar laser pumping approach to achieve both simultaneous and stable multibeam solar laser operation under solar tracking error condition is proposed here. By using a heliostat, solar radiation is firstly redirected to a parabolic mirror, secondarily concentrated by an aspheric lens, and finally absorbed by four Nd:YAG rods within a pump cavity using a homogenizer. Zemax® and LASCAD™ analysis demonstrate that four simultaneous and stable 1064-nm continuous-wave solar laser emissions with similar multimode power levels can be achieved even with azimuthal solar tracking errors up to ± 0.5 deg. The variation on the multimode solar laser power of the four rods is significantly reduced from 32.38% and 55.52% without the homogenizer to 0.00% and 0.21% with the homogenizer for ± 0.1 deg and ± 0.2 deg azimuthal solar tracking error, respectively. More importantly, simultaneous and stable TEM00 mode solar laser emissions from the four rods are also numerically attained under solar tracking error condition.

Stable Emissions from a Four-Rod Nd:YAG Solar Laser with ±0.5° Tracking Error Compensation Capacity

“…End-side-pumping schemes lead to higher efficiencies; however, focusing the concentrated solar radiation onto the end face of a single laser rod requires a highly accurate STS [15]. Therefore, multi-rod end-side-pumping solar laser designs were numerically studied, demonstrating the higher efficiency of end-side-pumping configurations as compared to that of side-pumping, while attaining high solar tracking error compensation capacity [20,21]. Furthermore, multibeam laser systems hold tremendous potential for significantly reducing processing time in industry [22].…”