Optical fiber 110 may be placed at or near focal point 117 of lens 105 for collecting the converged light. [0057]FIGS. 2A and 2B are a side view and a top view of lens 120, respectively, to illustrate the spherical geometry of lens 120 and the convergence of lights 115, 135 and 205 from different directions to a center point 210 of the spherical outer surface 215 having a radius R of lens 120.