4 Optics (17 hours)

4.1 Geometrical optics

4.1.1 Lens separation

4.1.2 Chromatism in lens combination

4.2 Interference

4.2.1 Interference in thin films (reflected and transmitted light)

4.2.2 Fringes produced by a wedge-shaped thin film

4.2.3 Newton’s rings (both reflected and transmitted case)

4.2.4 Determination of wavelength of light and refractive index of liquid by using Newton’s rings

4.3 Diffraction

4.3.1 Introduction: Fresnel and Fraunhoffer’s diffraction

4.3.2 Fraunhoffer’s diffraction at single slit

4.3.3 Intensity distribution in the diffraction pattern due to a single slit

4.3.4 Multiple slits, diffraction grating

4.3.5 X-ray diffraction, X-rays in material testing

4.4 Polarization

4.4.1 Introduction: double refraction, Nichol prism (construction and uses)

4.4.2 Retardation plate (quarter and half wave plates), plane, elliptical and circular polarized light

4.4.3 Optical activity, specific rotation

4.5 Laser

4.5.1 Introduction: Laser and ordinary light, properties of laser

4.5.2 Induced absorption, spontaneous and Stimulated emission, active medium, population inversion, metastable state

4.5.3 Pumping (types: optical, electrical, chemical and heating)

4.5.4 He-Ne laser, semiconductor Laser

4.5.5 Uses of laser

4.6 Fiber Optics

4.6.1 Introduction: Propagation of light wave

4.6.2 Types of optical fiber: step index and graded index

4.6.3 Fiber transmission – single and multimode, self focusing, acceptance angle and numerical aperture

4.6.4 Applications