finesse.gaussian.BeamParam.w0

property BeamParam.w0

The radius of the waist, $w_0$, of the beam, in metres.

Computed as,

$$w_0 = \sqrt{\frac{z_R \lambda}{n_r \pi}},$$

where $z_R$ is the Rayleigh range (given by BeamParam.zr, or BeamParam.imag), $\lambda$ is the beam wavelength (given by BeamParam.wavelength) and $n_r$ is the refractive index of the associated medium (given by BeamParam.nr).

Getter

Returns the beam waist-size.

Setter

Sets the beam waist-size.