Calculating the beam waist of a Guassian laser beam as a function of propagation distance

The geometry and behaviour of a Guassian laser beam can be governed by a set of beam parameters

beamWidth <- function(w0, wavelength, z) w0*sqrt(1+(z*(wavelength/1e6)/(pi*w0^2))^2)

w0 = 0.1
wavelength = 532
z = 10
beamWidth(w0, wavelength, z)

## [1] 0.1014237

The shiny application can be used to easily find the beam width of a Guassian laser beam, common in laboratory experiments. Consequently other useful parameters can be calculated from the beam width, such as the beam intensity, divergence and radius of curvature.

Equation for source Anupam Garg, Classical Electrodynamics in a Nutshell