finesse.gaussian.BeamParam.psi

property BeamParam.psi

Gouy phase, $\psi$, of the Gaussian beam.

Computed as,

$$\psi = \arctan{\left(\frac{z}{z_R}\right)},$$

where $z$ is the distance to the waist position (given by BeamParam.z, or BeamParam.real) and $z_R$ is the Rayleigh range (given by BeamParam.zr, or BeamParam.imag).

Hint

Use BeamParam.gouy() to compute the Gouy phase as a function of any of the above dependent arguments.

Getter

Returns the Gouy phase (in radians) of the beam parameter. Read-only.