Bessel beams: diffraction in a new light

Fourier transform of a ring – and this was how Durnin et al. [3] (see also the tutorial account in [14]) initially observed a Bessel beam. A ring (an annular slit) was placed in the back focal plane of a lens to form the beam, using a setup similar to that shown in figure 4. The opening angle of this cone is given by: tan y ¼ d 2f ð7Þ

  Light, Beam, Fourier, Bessel, Bessel beams, Diffraction in a new light, Diffraction