<p>A fiber optic comprises fibers each of which has a core made of a core glass for transmitting a light and a clad which covers the outer peripheral part of the core and is made of a clad glass having a refractive index lower than that of the core glass, and an absorber glass which is disposed between the fibers and absorbs the light leaking from the fibers. The fibers are bundled and integrated with each other. The absorber glass contains Fe<SUB>3</SUB>O<SUB>4 </SUB>that is an iron oxide crystal.</p>
