Wavefront healing

Figure 23 (also in FGDP) shows another example of ray bending.

 

heal
Figure 23 The first frame on the left shows a plane wave just after it has been distorted into a wavy shape by the thin-lens term. After this the thin-lens term vanishes. Subsequent frames show the effect of increasing amounts of diffraction. Notice the lengthening of the wave packet and the healing of the first arrival. (FGDP, p. 213, figure 10-22)

The first frame on the left shows a plane wave just after it has been distorted into a wavy shape by the thin-lens term. After this the thin-lens term vanishes. Later frames show the effect of increasing amounts of diffraction.