A scanning microinterferometer with correction of errors caused by overlapping 'ghost' images.

An experimental setup has been built to correct the errors caused by overlapping 'ghost' images when scanning and integrating measurements are carried out with the Jamin-Libedef interference microscope. First a reference field with the object, producing the 'ghost' image, is scanned and the values of the optical path difference (OPD) of each point in the reference field are stored in a computer. Subsequently, the OPD of the object to be measured is calculated for each point by adding the measuring result to the average OPD of five points, located around the corresponding point in the reference field.