Gaussian_spot_size_FWHM

plasmapy.formulary.laser.Gaussian_spot_size_FWHM(

beam_waist_radius: Annotated[Quantity, Unit('m')],

) → Annotated[Quantity, Unit('m')]

Calculate the Full Width at Half Maximum spot size \(FWHM\) at focus given the beam waist radius of a Gaussian beam \(w_0\).

The FWHM spot size of a Gaussian beam is calculated using:

\[FWHM = w_0 \sqrt{2 \ln {2}},\]

where \(w_0\) is the beam waist radius of the beam.

Parameters:

beam_waist_radius (Quantity) – beam waist radius of the Gaussian beam (convertible to nm).

Returns:

FWHM – The FWHM spot size of the Gaussian beam for the given beam waist.

Return type:

Quantity

See also

Gaussian_beam_waist_radius

Notes

For details, see Gaussian beam.

Examples

>>> import astropy.units as u
>>> Gaussian_spot_size_FWHM(7 * u.um)
<Quantity 8.242e-6 m>