Fresnel Assumptions

  1. The entire wavefront can be divided into a large number of elements or zones of small area such that each of these elements acts as a source of secondary waves emitting waves in all directions.
  2. The effect at any point “O” will be the resultant of the secondary wavelets reaching “O” from various elements of the wavefront.
  3. The effect at any point due to a particular zone depends on (a). the distance of point from the zone. (b). the inclination of the point with reference to zone under consideration.(c). area of the zone.