Huygens-Fresnel principle پروز ِ هویگنس-فرنل parvaz-e Huygens-Fresnel
*Fr.: principe Huygens-Fresnel*
A development of → *Huygens' principle*
stating that every point on a → *wavefront* acts, at a given
instant, as a source of outgoing secondary spherical waves.
The secondary wavelets mutually interfere and the
resulting net light amplitude at any position in the outgoing wavefront
is the vector sum of the amplitudes of all the individual wavelets.
Using this principle, Fresnel calculated with a high accuracy the
distribution of light in → *diffraction pattern*s.
The Huygens-Fresnel principle was put on a firm theoretical basis by Kirchhoff and
expressed as an integral derived from the → *wave equation*. → *Huygens*;
→ *Fresnel diffraction*; → *principle*. |