What is Light?
Light is a type of energy in the form of electromagnetic radiation of a wavelength which can be detected by the human eye.

Photometry is the science of the measurement of light, in terms of its perceived brightness to the human eye.

As the sensation of vision is stimulated through optic nerve, the study of vision is called as Ophthalmology.
Based on emission of the light from body:
  1. Self Luminous - Emits light from itself (E.g. Sun)
  2. Non Luminous - Depends on Self Luminous (E.g. Planets)
Theories of Light
  1. Newtons Corpuscular Theory
  2. Huygens Wave Theory
  3. Quantum theory of radiation
  4. Electromagnetic waves
Properties of Light
  • Effects of Materials on Light
  • Reflection
  • Refraction
  • Dispersion
  • Total Internal Reflection
  • Interference
  • Diffraction
  • Scattering of Light
  • Polarization