Waves And Optics

 

Linear Harmonic Oscillator (LHO)

LHO. Free and forced vibrations. Damping. Resonance. Sharpness of resonance. Acoustic, optical, and electrical resonances: LCR circuit as an example of the resonance condition. A pair of linearly coupled harmonic oscillators --- eigenfrequencies and normal modes.

Waves:

Plane progressive wave in 1-d and 3-d. Plane wave and spherical wave solutions. Dispersion: phase velocity and group velocity.

Fermat's principle:

Fermat's principle and its application on plane and curved surfaces.

Cardinal points of an optical system:

Two thin lenses separated by a distance, equivalent lens, different types of magnification, Helmholtz and Lagrange's equations, paraxial approximation, introduction to matrix methods in paraxial optics – simple application.

5. Wave theory of light:

Huygen’s principle; deduction of law of reflection and refraction.

Interference of Light:

Condition of sustained interference by analytical treatment, Division amplitude and division of wave front, methods for production of interference fringes by biprism and determination of wavelength, measurement of thickness of thin films, colour of a thin film in reflected and transmitted light, Haidinger’s fringe, Theory of Newton’s rings. Determination of wavelength and refractive index using Newton Ring apparatus .

Interferrometer:

Michelson’s interferometer and its theory relating to the formation of circular fringe’s, Determination of wavelength of a source and small difference of wave lengths in D lines by Michelson’s interferometer, standardization of a meter by Michelson’s interferometer.

Diffraction of light:

Fresnel and Fraunhofer class of diffraction, Fresnel’s half period zones, zone plate its similarity with convex lens. Diffraction at straight edge, circular aperture.

Elements of fiber optics:

Construction of optical fibers, image formation, numerical aperture, structure--step index, graded index, uses.