INFLUENCE OF ABERRATIONS ON THE PRECISION OF SHAPE MEASUREMENTS BY FIZEAU INTERFEROMETRY

The realisation of high resolution X-UV optics will be possible when o ne will be able to manufacture and control substrates which have shape errors notably reduced as compared to the state of the art. To make h igh precision shape controls by means of interferometry, the influence of each element of the device must be studied. Several articles which deal with the influence of the aberration on the measurement precisio n have been already published. However, a global investigation had nev er been done. Using a geometrical approach, the work exposed here disc usses the entire problem of phase errors and distortion due to the geo metric aberrations of the Fizeau interferometer. An analysis of the re sults concludes the investigation.