Q. Multimode for transmitting optical signals?
- Multiple beams from light source travel through core at different paths
- Multimode step-index fiber
- Density remains constant from centre to edges
- Light moves in a straight line until it reaches the cladding
- A few beams penetrate the cladding and are lost while others are reflected down the channel to the destination
- Consequently beams reach the destination at different times and the signal mayn't be the same as that which was transmitted
- To address this problem and to permit for more precise transmissions, multimode graded-index fiber may be used
- Index demotes to the index of refraction
- Graded-index demotes to varying densities of the fiber highest at centre and decreases at edge