Gaussian beams

A Gaussian beam of a given wavelength may be characterised by a beam waist radius, omega_0 at z=0. Given this and the wavelength the beam radius at any distance z, together with the radius of curvature of the beam may be calculated from the two equations below.

gaussianeq1gaussianeq2

 

 

The Gaussian beam solution also requires an anomalous phase term, which describes how the phase differs from that of a plane wave at a given z:

gaussianeq3

 

We make the transition from single mode waveguide modes to free-space gaussian modes by using corrugated feedhorns. These create a high quality 98% pure gaussian beam.