Patent ID: 7680390
Filing Date: 2010-03-16
Classification: G02B

Abstract:
1. A polymer clad optical fiber comprising: an outer core provided on an outer circumference of an inner core formed from quartz glass, the outer core being formed from fluorine-doped glass having a refractive index lower than that the refractive index of the inner core; and a polymer cladding provided on an outer circumference of the outer core and formed from a polymer, wherein if the diameter of the inner core is taken as a if a relative refractive index difference between the inner core and the outer core is taken as Δ if a relative refractive index difference between the outer core and the cladding is taken as Δ if a relative refractive index difference between the outer core and the polymer cladding at a high temperature is taken as Δ if a relative refractive index difference between the outer core and the polymer cladding at a low temperature is taken as Δ if a parameter Y is defined as Y=Δ then a relationship is established in which, when the parameter X is within a range of 1.8≦X≦2.0, the Ymin is 0.25≦Ymin≦0.84X−0.68, and the Ymax is 0.25≦Ymax≦0.84X−0.68, and, when X is within a range of 2.0≦X≦2.2, the Ymin is 0.48X−0.71≦Ymin≦−2/9X+13/9, and the Ymax is 0.48X−0.71≦Ymax≦−2/9X+13/9.