Experimental parameters, as well as chemical and morphological parameters, were investigated with the purpose of improving the performance of the previous type plastic hollow fibers. The dielectric layer was identified as β and γ AgI. The dielectric layer thickness (t) was measured and was found to be dependent on the iodination time (T) according to the relation t = T0.37. The thickness of the dielectric layer influenced the transmission through the hollow fiber by shifting absorption maxima and reducing the smoothness of AgI layer. The best focal lens of the coupling lens (ZnSe) was found to be 200 mm, and the colinearity angle between the beam and the fiber could deviate ±5° from O° angle. The parameters of the new type of fibers were measured and found considerably improved. Employing cooling and pulse power reduced the heating and increased the lifetime of the fiber.