Differentiate between step index and graded index optical fiber. Please concise and brief.

Answer

Both types are multimode fiber .

Step Index Fiber: There is an abrupt change in the density of the material of core and cladding. So internal reflection occurs at different angles and they reach to their destination at various pace and time. There are two sorts of light signals one that travels straight and the other type that adopts a curved path. So the internally reflected signals reach to their destination separately and with irregular timing. So the is a lack of synchronization and some time serious data loss due to non regular fashion of transfer .

Graded Fiber Index: in this case there is gradual decrease in the density of the material from core to cladding so the internally reflected light signal adopt a uniform way, it means that they reach to their destination at the same time and hence no problem of synchronization or data loss.