01
Geometrical Optics
Geometrical optics approximates light as rays and is especially useful when wavelengths are small compared with relevant geometric dimensions.
n₁ sin θ₁ = n₂ sin θ₂
02
Interference
Interference results from superposition of coherent waves. Constructive interference increases amplitude while destructive interference reduces it.
03
Diffraction
Diffraction describes the spreading and interference of waves around apertures and obstacles. It establishes fundamental limits on optical resolution.