Incoming solar energy is firstly collected 137 small parabolic mirrors, 180mm in diameter, 210mm in focal length and
then coupled by 137 optical fibers with 2mm in diameter each, to a diffusion bounded thin-disk Nd:YAG laser material.
The flexibility of optical fiber allows the placement of laser cavity in a convenient place away from the solar collection
mirrors. The conical polishing of the fiber output sections permits further enhancement of pump light absorption by the
Nd:YAG thin-disk, diffusion bounded to an undoped YAG cap with 80mm maximum diameter. For optimal pumping
condition with 1.8mm diameter polished tip, 20W laser power was numerically calculated, corresponding to a collection
efficiency of 5.9 W/m<sup>2</sup>. M<sup>2</sup> factors of M<sub>x2</sub>=88.5 and M<sub>y2</sub>=89.4 were also attained, indicating an almost symmetrical
absorption profile. The proposed scheme can provide a solution to the thermal problems that has plagued the solarpumped
lasers for many years.