title: Diffraction gratings: a sign convention on order numbers for use in a computer program.
abstract: In ray tracing an optical system containing diffraction gratings on a computer, a sign convention on order numbers is necessary. The purpose of this paper is to present a method for easily determining the sign of an order number and to compare the results of this method with those of several commercially available computer programs.
authors.forename: M E
authors.initials: ME
authors.lastname: Wilson