Caution
Fill in all input cells.
Choose all parameters unit.
n can be either a numeric value or the reference of a glass from the catalog. If a reference of a glass is selected, the calculation considers the refraction index of this glass at the generic wavelength lam defined in the page accessible by the general parameters/wavelength link.
e is positive.
Raddii are algebraic or infinite. Enter "infinite" for a plane surface.
Positive direction is according to the sense of the horizontal arrow provided for this purpose.