Vol. 35, Issue 4, pp. 913-918 (2005)

Abstract

In the previous article (see Optica Applicata 31(2), 2001, pp. 373–6) on laser diode pumping of an infrared-to-visible upconversion fiber laser emitting at 544 nm, special attention was paid to the role of focusing of the incident pumping power. This paper discusses the role of the wavelength dependence of the pumping beam, in particular, the appearance of undesired side fluorescences at 660 and 850 nm, and also the distribution of the pumping power along the fiber length.