Abstract: The concept of wavefront function and its application in Young’s double-slit interference and thin-film interference using the wavefront function method are introduced. In comparison with the traditional light path method discussing the light interference, the wavefront function method fully reflects the physical thought of wave, portrays the physical image of the propagation and superposition of electromagnetic waves, which helps students understand the concept of wave deeply.

Key words: wavefront function method, optical path, interference, diffraction