Figure 2
Illustration: Alan Stonebraker

Figure 2: Numerical simulations of an image of the letters “EIT” (left) after traversing the distance of two typical Rayleigh lengths in free space (middle) and in a diffusive atomic vapor with diffraction compensation (from [7]). (A Rayleigh length is the distance from the focus plane the beam travels before its diameter expands to twice its minimum size.)