Determination of the positioning uncertainties for a traceable measurement of the Modulation Transfer Function MTF

Abstract

In recent years, PTB has established a measuring setup for determining the Modulation Transfer Function (MTF) conforming to a setup described in ISO 9335. It is designed to measure the MTF of lenses with focal lengths between 25 and 150 mm on the optical axis and in the image field of the tested lens within an angular range of up to ±30° to the optical axis. To be able to perform traceable calibrations, thorough investigations and determination of several influencing variables was necessary. The experimental determination of the uncertainties of the angular and lateral positioning system is described in this contribution.