MODULE : 5
CHAPTER : 3
FIBER OPTICS
Optic fibre
An optical fiber is a thin fiber of glass or
plastic that can carry light from one end
to the other. The study of optical fibers is
called fiber optics
Structure of fiber optic cable
Typically a fiber optic cable contains three basic components
Core- which carries the light signals.
Cladding- which surrounds the core with a lower refractive index.
Sheath- which protects the fragile core and cladding within it.
n1 = refractive index of core
n2 =Refractive index of cladding
n1 ˃ n2
ENGINEERING PHYSICS PHT-100/110 | MOHAMMED JANISH K – ASST. PROFESSOR | MEA ENGINEERING COLLEGE | PERINTHALMANNA | 9995831836 1
, Principle of propagation of light through optic fiber
Principle – Total internal reflection
If light ray travelling through denser medium to rarer medium, and angle of
incidence is greater than
the critical angle. The light
ray reflect back in to the
denser medium this
phenomenon is known as
total internal reflection.
There for by multiple total
internal reflections light is
transmitted through optic
fiber.
ENGINEERING PHYSICS PHT-100/110 | MOHAMMED JANISH K – ASST. PROFESSOR | MEA ENGINEERING COLLEGE | PERINTHALMANNA | 9995831836 2
CHAPTER : 3
FIBER OPTICS
Optic fibre
An optical fiber is a thin fiber of glass or
plastic that can carry light from one end
to the other. The study of optical fibers is
called fiber optics
Structure of fiber optic cable
Typically a fiber optic cable contains three basic components
Core- which carries the light signals.
Cladding- which surrounds the core with a lower refractive index.
Sheath- which protects the fragile core and cladding within it.
n1 = refractive index of core
n2 =Refractive index of cladding
n1 ˃ n2
ENGINEERING PHYSICS PHT-100/110 | MOHAMMED JANISH K – ASST. PROFESSOR | MEA ENGINEERING COLLEGE | PERINTHALMANNA | 9995831836 1
, Principle of propagation of light through optic fiber
Principle – Total internal reflection
If light ray travelling through denser medium to rarer medium, and angle of
incidence is greater than
the critical angle. The light
ray reflect back in to the
denser medium this
phenomenon is known as
total internal reflection.
There for by multiple total
internal reflections light is
transmitted through optic
fiber.
ENGINEERING PHYSICS PHT-100/110 | MOHAMMED JANISH K – ASST. PROFESSOR | MEA ENGINEERING COLLEGE | PERINTHALMANNA | 9995831836 2