title: Investigation of the wavelength accuracy of brewer spectrophotometers.
abstract: The wavelength accuracy of the Brewer spectrophotometer in the 280-360-nm spectral range is improved by a new grating-drive mechanism and a new dispersion function derived from the Brewer geometry. With the new mechanism, the reproducibility of wavelength settings for spectral emission lines is better than 0.3 pm (0.0003 nm) and, with a thermally compensated version, the effect of temperature is less than 0.4 pm K(-1). The new dispersion function fits spectral line positions better than the standard function and is less prone to extrapolation error. Applying the new function to data from four new and ten standard drives shows that the new drives perform as well as the best of the standard ones and much better than the majority.
authors.forename: J
authors.initials: J
authors.lastname: Gröbner
authors.forename: D I
authors.initials: DI
authors.lastname: Wardle
authors.forename: C T
authors.initials: CT
authors.lastname: McElroy
authors.forename: J B
authors.initials: JB
authors.lastname: Kerr