Bend-insensitive multimode optical fiber of optical cable used in data transfer device, has concentric regions with grave stepped refractive index profile, which are formed on edge of refractive index trench of middle cladding portion

摘要

The optical fiber (1) has a fiber core with an alpha-index profile and a cladding which surrounds the fiber core. The cladding includes an inner cladding portion (3), a middle cladding portion (4) and an outer cladding portion (5) made of pure quartz glass. The middle cladding portion is provided with a refractive index trench. Several concentric regions (6) having grave stepped refractive index profile are formed on edge of refractive index trench.