Patent ID: 6078715
Filing Date: 2000-06-20
Classification: G02B

Abstract:
An optical fiber comprising:an inner core having a refractive index profile in which refractive indices increase toward the center axis thereof;an outer core provided outside of said inner core and having a constant refractive index not more than the minimum refractive index of said inner core; anda cladding provided outside of said outer core and having a refractive index smaller than said constant refractive index of said outer core;wherein total refractive index difference (.DELTA.n.sub.total), defined as the difference between the maximum refractive index of said inner core and the refractive index of said cladding, is not less than 0.015 and not more than 0.1; and a outside core diameter (d.sub.1) of said outer core is not less than 100 .mu.m and not more than 500 .mu.m.