Fibre Optics
Applications
Allowed modes
Distortion
Attenuation
Smart structures in aeronautic
Attenuation is the reduction in power of the light signal as it is transmitted
Dispersion is a phenomenon related to the variation in velocity of different frequencies (wavelengths) or different modes.
Environmental monitoring
Industrial monitoring and measurement
Chemical sensing
Single Mode Fiber Optic Cable
Multimode Fiber Optic Cable
Single Mode fiber optic cable has a small diametral core that allows only one mode of light to propagate.
Multimode fiber optic cable has a large diametral core that allows multiple modes of light to propagate.
Attenuation is caused by passive media components, such as cables, cable splices, and connectors.
As the pulses travel on the fiber due to broadening, slowly they start overlapping with each other.
Intra-modal or Chromatic dispersion (present in single mode an multimode optical fiber). This dispersion is due to finite bandwidth of the signal
Material dispersion: This is due to intrinsic properties of the material, glass
Waveguide dispersion: This is due dispersive nature of the bound medium. In a bound medium like the optical fiber, the velocity is a function of frequency.
Inter-modal dispersion (present in only multimode optical fiber). This dispersion is due to change in velocity from one mode to other.