پروز ِ هویگنس parvaz-e Huygens
*Fr.: principe de Huygens*
Every point of a → *wavefront* may be considered as a center of a
secondary disturbance which gives rise to spherical wavelets, and the
wavefront at any later instant may be regarded as the envelope of
these wavelets. This statement suffices to account for the laws of
→ *reflection* and → *refraction*,
and the approximately straight line propagation of light through large apertures, but
it fails to account for → *diffraction*,
the deviations from exact straight line propagation of light. Huygens' principle was later
extended by Fresnel and led to the formulation of
→ *Huygens-Fresnel principle*, which is of great importance
in the theory of diffraction. → *Huygens*; → *principle*. |