Graded Index Multi Mode Fiber

Graded index multimode optical fibers optimized for signal transmission at 850 and 1300 nm are available with 50 125 62 5 125 and 100 140 µm core cladding diameters.

Graded index multi mode fiber.

The advantage of the multi mode graded index compared to the multi mode step index is the considerable decrease in modal dispersion. This type of fiber is normalized by the international telecommunications union itu t at recommendation g 651 1. 50μm and 62 5μm variants. Thus 62 5 125 μm multi mode fiber has a core size of 62 5 micrometres μm and a cladding diameter of 125 μm.

Modal dispersion can be further decreased by selecting a smaller core size less than 5 10μm and forming a single mode step index fiber. The light wave that travels inside the fiber changes its behaviour with time while travelling inside it. Because of the larger core size compared to single mode fiber these fibers provide a higher transmission capacity and are used for short range communication networks and high speed transmission applications. The large diameter of the core allows multiple rays to propagate through the fiber.

Graded index fiber is of only one type that is multi mode fiber. Multi mode fibers are described by their core and cladding diameters. Suitable for light wave communication links and local area networks carrying voice video and data standard and high temperature up to 375 c versions. The transition between the core and cladding can be sharp which is called a step index profile or a gradual transition which is called a graded index profile.

High temperature coatings for 150 c and 300 c. Graded index multimode fiber. Graded index fiber is a type of fiber where the refractive index of the core is uniform at the center core and then it decreases towards core cladding interface. Thorlabs graded index grin multimode fiber provides lower modal dispersion and less bend loss than traditional multimode step index fiber with a broad operating wavelength range from 800 1600 nm see the graphs tab for attenuation plots over this range.

Index profiles is in the shape of a parabolic curve for α 2.