M.Sc. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2017.
Third Semester
Physics
Paper III LASERS AND NON LINEAR OPTICS
2 20733-A
Time 3 Hours Max. Marks 70
SECTION — A
Answer any FIVE questions. 6 30 Marks)
All questions carry equal marks.
1. Explain the spatial and temporal coherence in lasers.
2. Explain the role of feedback in a laser cavity.
3. Explain the phase matching condition in non linear optics.
4. Explain the parametric generation of light.
5. Write a note on Fourier transform holography.
6. Explain the optical data processing in holography.
7. Write a note on fibre optic rays and modes.
8. Give the applications of fibre optics.
SECTION — B
Answer ALL questions. 10 40 Marks)
All questions carry equal marks.
9. Obtain the relation between Einstein coefficients and explain the significance
of Einstein coefficients.
Or
Explain the instrumentation and working of He-Ne laser.

10. Explain the basic principle of non linear optics and discuss the second and
third harmonic generations.
Or
Explain optical mixing and discuss the frequency conversion in non linear
optics.
11. Give the basic theory of Holography and explain the pattern recognition in
holography.
Or
Describe the principle and working of Fourier transformation spectroscopy.
12. Distinguish between step index fibre and graded index fibres and explain ray
optic representation.
Or
Explain the attenuation and material dispersion in optical fibres.
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