Deck 6: Fiber Optics Fabrication Techniques and Phenomena

Question 1

Self-phase modulation can be used for

A)enhancing the core diameter
B)wavelength shifting
C)decreasing the attenuation
D)reducing the losses in the fiber

Answer 1

wavelength shifting

Question 2

The beating between light at different frequencies or wavelengths in multichannel fiber transmission causes

A)attenuation
B)amplitude modulation of channels
C)phase modulation of channels
D)loss in transmission

Answer 2

phase modulation of channels

Question 3

What is different in case of cross-phase modulation from self-phase modulation?

A)overlapping but same pulses
B)overlapping but distinguishable pulses
C)non-overlapping and same pulses
D)non-overlapping but distinguishable pulses

Answer 3

overlapping but distinguishable pulses

Question 4

When three wave components co-propagate at angular frequency w1, w2, w3, then a new wave is generated at frequency w4, which is given by

A)w4 = w1-w2-w3
B)w4 =w1+w2+w3
C)w4 =w1+w2-w3
D)w4 =w1-w2+w3

Question 5

_____________ results from case of nonlinear dispersion compensation in which the nonlinear dispersion compensation in which the nonlinear dispersion compensation in which the nonlinear chirp caused by self-phase modulation balances, postpones, the temporal broadening induced by group velocity delay.

A)four wave mixing
B)phase modulation
C)soliton propagation
D)raman scattering

Question 6

What is a fundamental necessity in the fabrication of fibers for light transmission?

A)same refractive index for both core and cladding.
B)pump source
C)material composition of fiber
D)variation of refractive index inside the optical fiber

Question 7

Which materials are unsuitable for the fabrication of graded index fiber?

A)glass-like-materials
B)mono-crystalline structures
C)amorphous material
D)silica based material

Question 8

How many different categories are available for the methods of preparing optical glasses?

A)1
B)2
C)3
D)4

Question 9

What is the first stage in liquid-phase-technique?

A)preparation of ultra-pure material powders
B)melting of materials
C)decomposition
D)crystallization

Question 10

Which processes are involved in the purification stage in liquid-phase-technique?

A)filtration, co-precipitation, re-crystallization
B)decomposition, filtration, drying
C)doping, drying, decomposition
D)filtration, drying, doping

Question 11

At what temperature range, does the melting of multi components glass systems takes place?

A)100-300 degree celsius
B)600-800 degree celsius
C)900-1300 degree celsius
D)1500-1800 degree celsius

Question 12

Fiber drawing using preform was useful for the production of graded index fibers.

Question 13

The minute perturbations and impurities in the fiber drawing process using preform technique can result in very high losses of

A)between 500 and 1000 db/km
B)between 100 and 300 db/km
C)between 1200 and 1600 db/km
D)more than 2000 db/km

Question 14

The liquid-phase melting technique is used for the production of fibers

A)with a core diameter of 50?m.
B)with a core diameter less than 100?m.
C)with a core diameter more than 200?m.
D)with a core diameter of 100?m.

Question 15

Graded index fibers produced by liquid-phase melting technique are less dispersive than step-index fibers.

Question 16

Which of the following is not a technique for fabrication of glass fibers?

A)vapor phase oxidation method
B)direct melt method
C)lave ring method
D)chemical vapor deposition technique

Question 17

_____________ technique is method of preparing extremely pure optical glasses.

A)liquid phase (melting)
B)radio frequency induction
C)optical attenuation
D)vapor phase deposition (vpd)

Question 18

Which of the following materials is not used as a starting material in vapor-phase deposition technique?

A)sicl4
B)gecl4
C)o2
D)b2o3

Question 19

P2O5 is used as a _____________

A)dopant
B)starting material
C)cladding glass
D)core glass

Question 20

How many types of vapor-phase deposition techniques are present?

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

Question 21

___________ uses flame hydrolysis stems from work on soot processes which were used to prepare the fiber with losses below 20 dB/km.

A)outside vapor phase oxidation
B)chemical vapor deposition
C)liquid phase melting
D)crystallization

Question 22

Complete the given reaction

A)2hcl
B)4hcl
C)2cl2
D)4cl2

Question 23

In modified chemical vapor deposition, vapor phase reactant such as _________ pass through a hot zone.

A)halide and oxygen
B)halide and hydrogen
C)halide and silica
D)hydroxides and oxygen

Question 24

_________ is the stimulation of oxide formation by means of non-isothermal plasma maintained at low pressure in a microwave cavity surrounding the tube.

A)outside vapor phase oxidation (ovpo)
B)vapor axial deposition (vad)
C)modified chemical vapor deposition (mcvd)
D)plasma-activated chemical vapor deposition (pcvd)

Question 25

Only graded index fibers are made with the help of vapor-phase deposition techniques. State whether true or false.