Otis G, Lit J W
Appl Opt. 1975 May 1;14(5):1156-60. doi: 10.1364/AO.14.001156.
A He-Ne laser beam is used here to illuminate a razor blade at edge-on incidence. The incident light is found to be scattered into a single straight cone of circular cross section. The tip of this cone of diffracted light lies at the point of incidence, its axis coincides with the prolongation of the razor edge, and its halfangle is equal to the angle of incidence. Such cones formed by a family of diffracted rays are basic to the so-called geometrical theory of diffraction. However, the properties and geometrical laws associated with the diffracted rays are derived analytically here by application of the boundary diffraction wave theory. The experimental results are in agreement with theoretical predictions.
