Cochin University of Science and Techology (CUST) 2007 B.Tech Electronics and Communications Engineering opto electronics - Question Paper

opto electronics (November 2007)

1a. write Newton's lens formula and discuss the symbols used.
b. discuss the propagation of light through step index fibre and find the expression for acceptance angle of the fibre.
c. determine the numerical aperture of an optical fibre which has a core refractive index of 1.5 and cladding refractive index 1.47
2a. write notes on :
i. diffraction
ii. polarisation
b. explain how dispersion effect affects signal transmission through optical fibre.
c. determine Brewster angle for a light reflecting surface with refractive index 1.5
3 . write short notes on:
i. step index fibre
ii. graded index fibre
iii.single mode fibre
iv. multimode fibre
4 . define the structure of modes in slab wave guide
5 . define the structure and pumping of semiconductor laser diode.
6 . discuss the construction and working of
i. avalanche photo diode
ii. PN photo diode
7 . discuss in detail time division and wavelength division multiplexing techniques
8 . write notes on
i. optical receivers
ii. optical modulation
9a. discuss the construction of optical ICs
b. explain industrial application of lasers and optical fibre
10a.describe the military applications of optical fibres
b. explain the structure of Public Net Work with reference to optical fibre

Earning:   Approval pending.