Automatic concentric shaft reflectometer for use in the vacuum uv

Abstract
A vacuum uv reflectometer is described which makes use of a highly reproducible stepping motor drive system. The concentric shaft design eliminates many alignment problems common to other systems and makes possible a single flange mounting. The pulsed drive system is particularly well suited to automation, both from the standpoint of sample position control and the application of signal averaging techniques to improve the precision of reflectance measurements. Examples of both manual and automatic control systems are presented.