21PHY216 OPTICS PHYSICS PAPER – IV-

Unit I-

Wave Nature of Light and Interference: Light-electromagnetic spectrum, Rotating mirror method of determination of speed of light, Huygen’s principle, explanation of reflection and refraction, Fermat’s Principle, Phase change on reflection, total internal reflection, Young’s experiment-coherence, intensity distribution and visibility of fringes, Newton’s rings, Fresnel’s Biprism, interference in thin films, colours of thin films, interference at an air wedge, Michelson’s interferometer.

Unit II-

Diffraction: Fraunhoffer and Fresnel: Diffraction, Diffraction at a single slit, double slit, Diffraction by multiple slits, Diffraction grating, Resolving power, Rayleigh’s criterion, Resolving power of a grating and telescope, Fresnel diffraction, half period zone, zone plate, diffraction at a circular aperture and at a straight edge (qualitative treatment only).

Unit III-

Polarization: Polarization by reflection, Brewster’s law, Mauls law, Double refraction, Production and detection of linearly, circularly and elliptically polarized light, Quarter and half wave plates, Polaroid’s, Discussion on use of Polaroid sheets in preparing tinted sunglasses, Optical activity.

Unit IV-

Scattering of Light: A brief discussion on Tyndall effect, Rayleigh scattering and Raman effect, Blue of the sky and ocean, A qualitative account of fluorescence and phosphorescence, Raman effect: Classical and quantum theory of Raman effect, experimental method for studying Raman spectra, Raman spectrum, study of Raman effect using Lasers, intensity of Raman lines, Polarization of Raman lines, characteristic properties of Raman lines, applications of Raman effect.

Unit V-

Introduction to Lasers: Spontaneous and stimulated emission, density of states, Einstein’s A and B coefficients, Ratio of stimulated to spontaneous transitions in a system in thermal equilibrium, condition for amplification, population inversion, methods of optical pumping, energy level schemes of He-Ne and Ruby Laser, Properties and uses of Lasers, Basic concepts of holography, construction of hologram, Discussion on the use of holograms in daily life, Recording and reproduction of holograms.