OCN-Q4

What is the primary condition for total internal reflection to occur in an optical fiber?

• a) The angle of incidence must be less than the critical angle

• b) The angle of incidence must be equal to the critical angle

• c) The angle of incidence must be greater than the critical angle

• d) The refractive index of the core must be lower than the cladding

Total internal reflection occurs when light travels from a medium

• a) Lower refractive index to a higher refractive index

• b) Higher refractive index to a lower refractive index
  
  

• c) Medium of equal refractive index

• d) Vacuum to any medium

In an optical fiber, the core has a refractive index that is

• a) Equal to the cladding
  
  

• b) Higher than the cladding

• c) Lower than the cladding

• d) Dependent on the wavelength of light

The critical angle for total internal reflection in an optical fiber is determined by the refractive indices of which two materials?

• a) Core and air
  
  

• b) Core and cladding

• Cladding and air

• d) Core and glass

What happens to light that strikes the boundary between the core and cladding at an angle less than the critical angle?

• a) It is totally internally reflected

• b) It is partially reflected and partially refracted

• c) It is completely absorbed by the core

• d) It escapes into the cladding