Editing Field electron emission (section)

== Terminology and conventions ==
Equations in this article are written using the modern [[International System of Quantities]] (ISQ). Older field emission literature (and papers that directly copy equations from old literature) often work with [[Gaussian units]] such that they omit the physical constant [[Vacuum permittivity|''ε''<sub>0</sub>]]. In this article, all such equations have been converted to modern international form. 

Since work function is normally given with the unit electronvolt (eV), and for fields it is often convenient to use the unit volt per nanometer (V/nm); increasingly, this is normal practice in field emission research.  , Numerical values of universal constants given here are written in units derived from eV, V and nm, and calculated to seven significant figures using the 2006 values of the fundamental constants.