Understanding Light
Is light a wave or a particle? We are often asked this question but are seldom given the answers. Light is actually an electromagnetic wave that propagates in the form of two mutually perpendicular vector waves ( an electric wave and a magnetic wave). However, most of the phenomena in our daily life can be described using a scalar wavefunction. This theory is called scalar wave optics or simply wave optics. Applications of wave optics include microscopy, spectroscopy, interferometers, Liquid Crystal Displays(LCDs), optical discs, and many more. Ray optics is a special case of wave optics. This model of light is taken into consideration when dimensions of objects through or around which light waves propagate are much larger than the wavelength of light. Unlike wave optics, ray optics cannot explain phenomena like interference and diffraction. Ray optics is only valuable for explaining reflection, refraction which has applications in light guides, graded-index optical components, and opt
