Gaussian beam (Beam width or spot size)
Description
In optics, a Gaussian beam is a beam of electromagnetic radiation whose transverse electric field and intensity (irradiance) distributions are well approximated by Gaussian functions. For a Gaussian beam propagating in free space, the spot size (radius) will be at a minimum value at one place along the beam axis, known as the beam waist. For a beam of wavelength λ at a distance z along the beam from the beam waist, where the origin of the z-axis is defined, the variation of the spot size can be calculated by the waist size and the Rayleigh range.
Related formulasVariables
wz | The spot size (m) |
w0 | The waist size (m) |
z | The distance along the beam from the beam waist (m) |
zR | The Rayleigh range (m) |