Jawaharlal Nehru Technological University Hyderabad 2005-2nd Sem B.Tech Applied Electronics and Instrumentation III Supplementary s, ember/ember OPTO ELECTRONIC & LASER INSTRUMENTATION - Ques

Code No: RR321002 Set No. 4
III B.Tech II Semester Supplementary Examinations,
November/December 2005
OPTO ELECTRONIC & LASER INSTRUMENTATION
(Electronics & Instrumentation Engineering)
Time: three hours Max Marks: 80
ans any 5 ques.
All ques. carry equal marks
? ? ? ? ?
1. (a) Briefly discuss about the optical fibre construction details and show a figure for
transmission of light rays and explain about the refractive index distribution
with a graph.
(b) Write the equations for the total internal reflection of the light rays in a optical
fibre cable and derive the expression for the Numerical Aperture of the fibre.
[8+8]
2. (a) provide a point - to - point fiber optic communication link block diagram and
discuss the use of every block in detail.
(b) provide any 3 applications of optical fibers for instrumentation and discuss
them with the necessary figures. [8+8]
3. (a) Bring out the importance of Q Switching. Compare mechanical switching with
Electronic switching.
(b) CO2 laser is more efficient as compared to other gas lasers - Say “True” or
“False”. Justify your ans comparing the performances. [8+8]
4. (a) With a neat diagram discuss the interferometric method of measurement of
length.
(b) Write in detail about IR sources. [8+8]
5. (a) What is an Evanescent sensor? discuss.
(b) discuss the principle and working of a fiber Gyroscope. [8+8]
6. With neat diagrams discuss the subsequent applications of lasers in detail :
(a) Lasers in material processing.
(b) Laser fusion in power plants. [8+8]
7. (a) With the help of neat sketches discuss holographic character recognition?
(b) With the help of neat. sketches discuss recording and reconstruction of Fourier
Transform hologram? [8+8]
8. (a) What is a Bragg modulator?
(b) find expression for the bandwidth of a Bragg acousto - optic modulator.

Earning:   Approval pending.