optical fiber system-city and guilds telecommunication advanced dip

when you face to city n guilds exam these are the importants note you must know about

optical fiber system lession.

tutorials created by:H.L.C fernando.

terms which are mostly asked at papers

1)refraction

ans:changing the direction of the light when it travels one medium to another medium

 at the interface between both two mediums.

2)refractive index

ans:ratio between the speed of light in the free space and the speed of light in the gigen medium.

n=c/v

3)critical angle

ans:critical angle is the angle of incident ray above which total internal reflection occur.

4)core

ans:core is the inner section of optical fiber which is made out of high refracctive index materials (eg:-glass/plastic)

5)cladding

ans:cladding surrounds the core and it is also made out of dielectrical materials.

refractive index of cladding is lesser than core.

6)total internal reflection

ans:when light ray traels through the high refractive index medium to low refractive index medium

the angle of the incident ray is more than critical angle ray will be fully reflected to the same medium

that insident is called as total intenal reflection.

7)Numerical aperture

ans:NA define as capabilityvof gathering light in optical fiber.

8)Acceptance angle

ans:Acceptance angle is defined as the maximum external incidence angle for which the light will propagate in the fiber  

 or

upper limit for the angle of incident ray at air/outer medium core interference in order to confine the ray inside the core is acceptance angle.

9)Acceptance cone

ans:acceptance cone is define as the cone which the light rays should enter the fiber in order to be confined and guded inside the fiber.

10)Dispersion

ans:dispersion is broadening the width of a pulse in time domain while it propagets along the fiber.

Inter Symbol Interfernence.(ISI)

ans: ISI define as form of distrotion of a signal in which one symbol interference with subsequent symbols..