Optics

Paper Code: 
PHY202
Credits: 
03
Contact Hours: 
45.00
Max. Marks: 
100.00
Objective: 
This course familiarizes the students with the phenomenon of interference, diffraction, polarization, LASER  and holography to enable them to acquire sufficient understanding and knowledge to recognize the usefulness of these phenomena in everyday life and also stimulate their interest in Physics.
 
10.00
Unit I: 
Geometrical Optics
Fermat’s principle extremum path, Laws of reflection and refraction from Fermat’s principle, Refraction at a spherical surfaces (convex surface and concave surface) cardinal points ,construction of a image using cardinal points, Newton’s formula; Relationship between f1 and f2 ;Relationship between f1 , f2 , m1 and m2, Cardinal points of a coaxial system of two thin lens.
 
8.00
Unit II: 
Interference
Young’s double slit experiment, types of interference: division of amplitude, division of wave front, Coherence: temporal and spatial coherence, Interference in thin films, colour in thin films, Newton’s rings, Determination of wavelength and refractive index of liquid by Newton’s rings, Michelson interferometer, Applications of Michelson interferometer: determination of wavelength, difference of wavelength and thickness of thin films. 
 
9.00
Unit III: 
Diffraction
Fresnel diffraction: Fresnel’s assumptions, Half period zones, Distinction between interference and diffraction, Difference between Fresnel and Fraunhoffer diffraction, , diffraction at a  circular aperture, straight edge and thin slit, zone plate, difference between zone plate and a convex lens.
Franunhoffer diffraction: Diffraction at single slit, Diffraction at double slit, Diffraction at N slits( simple derivation), plane diffraction grating, dispersion by a grating, resolving power of a grating.
 
 
9.00
Unit IV: 
Polarization
Plane electromagnetic waves. E and B of linearly, circularly, elliptically polarized electromagnetic waves.
Polarization by reflection, Huygens theory of double refraction, production and Analysis of plane, circularly and elliptically polarized light, Quarter and half wave plate.
Optical activity, specific rotation, Biquartz and half shade polarimeters.
 
9.00
Unit V: 
LASER and holography
Difference between ordinary and LASER source, stimulated and spontaneous emission, Einstein A and B coefficients, Population inversion, Principle of laser action, Metastable states, Pumping, types of LASER, construction, working and energy levels schemes of He-Ne and Ruby laser, Applications of LASER.
Basic  concepts of holography, construction of hologram and reconstruction of image, important features of hologram and uses of holography.
 
Essential Readings: 
1. “A textbook of Optics”, Brijlal and Subramaniam, S.Chand  & Company Ltd.,23rd edition.
2. “Essentials of Lasers and non-linear Optics”,G.D.Baruah, Pragati Prakashan, Meerut.
 
References: 
1. “Text books of Optics and Atomic Physics”, D.P. Khandelwal, Himalaya Publishing House.
2. “Optics”, Ajoy Ghatak ,Tata Mc Graw Hill Pub.Co. Ltd, 2007.
3. “Physics Part II”, D.Halliday and R.Resnick, John Wiley & Sons, Inc., Newyork.
4. “LASERS: Theory and Applications”, K.Thyagrajan, A.K.Ghatak, Macmillan India Ltd.
 
Academic Year: