Huygens principle (HP) is a notion that goes back to the classical Traité de la Lumière (Treatise on Light) by Christiaan Huygens, which was published in 1690. In its original meaning, HP gives the following geometric description of the wave...

The Huygens–Fresnel principle (named for Dutch physicist Christiaan Huygens, and French physicist Augustin-Jean Fresnel) is a method of analysis applied to problems of wave propagation (both in the far field limit and in near field diffraction). It...