The technology of this application relates to the field of communication technologies, and an optical fiber raw material composition, an optical fiber, and an optical fiber product. The optical fiber raw material composition includes components of the following molar percentages: AlF.sub.3 10%-50%, BaF.sub.2 3%-20%, CaF.sub.2 3%-20%, YF.sub.3 1%-15%, SrF.sub.2 3%-20%, MgF.sub.2 3%-20%, and TeO.sub.2 1%-35%. The optical fiber prepared by using the optical fiber raw material composition provided in this disclosure can be used in aspects such as a mid-infrared band transmission optical fiber, an optical fiber amplifier, a fiber laser, and an optical fiber sensor.

A molding device and a molding method for an optical fiber preform are provided. The molding device includes a rotating mechanism, an extrusion mechanism, and a cylinder mold that is of a cylindrical structure with two ends each having an opening. After a hollow cladding sleeve is obtained by rotating the cylinder mold through the rotating mechanism, a molten core glass is then reversely extruded into the cladding sleeve in the cylinder mold from bottom to top by the extrusion mechanism to prepare the optical fiber preform.