beam_ellipticity

laserbeamsize.display.beam_ellipticity(dx, dy)

Calculate the ellipticity of the beam.

The ISO 11146 standard defines ellipticity as the “ratio between the minimum and maximum beam widths”. These widths (diameters) returned by beam_size() can be used to make this calculation.

When ellipticity > 0.87, then the beam profile may be considered to have circular symmetry. The equivalent beam diameter is the root mean square of the beam diameters.

Parameters:

• dx – x diameter of the beam spot

• dy – y diameter of the beam spot

Returns:

ellipticity – varies from 0 (line) to 1 (round) d_circular: equivalent diameter of a circular beam