Enter in the following parameters about the Gaussian beam. You can use scientific notation (e.g. 1550 nm = 1550e-9).

Wavelength (λ):

[m]

Beam Radius (at I_{o}e^{-2}):

[m]

Enter the following parameters about your lenses. Enter a negative focal length for convex (beam expanding) lenses. Leave fields blank if a lens is not used.

These equations are used to calculate the initial radius of curvature (R) and the initial beam radius (W).

In the equations above R is the radius of curvature, W is the beam radius, i is the square root of negative 1 and &lambda is the wavelength.
For a Gaussian beam propagating through a lens A=1, B=0, C=-1/f (where f is the focal length) and D=1.
For a Gaussian beam propagating through air A=1, B=d (where d is the distance), C=0 and D=1.