Deck 1: Fiber Optics Communication

Question 1

Who proposed the idea of transmission of light via dielectric waveguide structure?

A)christian huygens
B)karpon and bockham
C)hondros and debye
D)albert einstein

Answer 1

hondros and debye

Question 2

Who proposed the use of clad waveguide structure?

A)edward appleton
B)schriever
C)kao and hockham
D)james maxwell

Answer 2

kao and hockham

Question 3

Which law gives the relationship between refractive index of the dielectric?

A)law of reflection
B)law of refraction (snell's law).
C)millman's law
D)huygen's law

Answer 3

law of refraction (snell's law).

Question 4

The light sources used in fibre optics communication are :

A)led's and lasers
B)phototransistors
C)xenon lights
D)incandescent

Question 5

The ________ ray passes through the axis of the fiber core.

A)reflected
B)refracted
C)meridional
D)shew

Question 6

Light incident on fibers of angles________the acceptance angle do not propagate into the fiber

A)less than
B)greater than
C)equal to
D)less than and equal to

Question 7

What is the numerical aperture of the fiber if the angle of acceptance is 16 degree

A)0.50
B)0.36
C)0.20
D)0.27

Question 8

The ratio of speed of light in air to the speed of light in another medium is called as_________

A)speed factor
B)dielectric constant
C)reflection index
D)refraction index

Question 9

When a ray of light enters one medium from another medium, which quality will not change

A)direction
B)frequency
C)speed
D)wavelength

Question 10

An optical fiber has core-index of 1.480 and a cladding index of 1.478. What should be the core size for single mode operation at 1310nm?

A)7.31?m
B)8.71?m
C)5.26?m
D)6.50?m

Question 11

An optical fiber has a core radius 2?mand a numerical aperture of 0.1. Will this fiber operate at single mode at 600 nm?

A)yes
B)no

Question 12

What is needed to predict the performance characteristicsics of single mode fibers?

A)the intermodal delay effect
B)geometric distribution of light in a propagating mode
C)fractional power flow in the cladding of fiber
D)normalized frequency

Question 13

Which equation is used to calculate MFD?

A)maxwell's equations
B)peterman equations
C)allen cahn equations
D)boltzmann's equations

Question 14

A single mode fiber has mode field diameter 10.2?mand V=2.20. What is the core diameter of this fiber?

A)11.1?m
B)13.2?m
C)7.6?m
D)10.1?m

Question 15

The difference between the modes' refractive indices is called as

A)polarization
B)cutoff
C)fiber birefringence
D)fiber splicing

Question 16

A single mode fiber has a beat length of 4cm at 1200nm. What is birefringence?

A)2*10^?5
B)1.2*10^?5
C)3*10^?5
D)2

Question 17

How many propagation modes are present in single mode fibers?

A)one
B)two
C)three
D)five

Question 18

Numerical aperture is constant in case of step index fiber. State whether the statement is true or false.

Question 19

Plastic fibers are less widely used than glass fibers. State whether the statement is true or false.

Question 20

Which equations are best suited for the study of electromagnetic wave propagation?

A)maxwell's equations
B)allen-cahn equations
C)avrami equations
D)boltzmann's equations

Question 21

When ? is optical wavelength in vacuum, k is given by k=2?/?. What does k stand for in the above equation?

A)phase propagation constant
B)dielectric constant
C)boltzmann's constant
D)free-space constant

Question 22

Constructive interference occurs when total phase change after two successive reflections at upper and lower interfaces is equal to? (Where m is integer)

A)2?m
B)?m
C)?m/4
D)?m/6

Question 23

. When light is described as an electromagnetic wave, it consists of a periodically varying electric E and magnetic field H which are oriented at an angle

A)90 degree to each other
B)less than 90 degree
C)greater than 90 degree
D)180 degree apart

Question 24

A monochromatic wave propagates along a waveguide in z direction. These points of constant phase travel in constant phase travel at a phase velocity Vp is given by

A)vp=?/?
B)vp=?/c
C)vp=c/n
D)vp=mass/acceleration

Question 25

A most important velocity in the study of transmission characteristics of optical fiber is

A)phase velocity
B)group velocity
C)normalized velocity
D)average velocity