Modified interferometer Fizeau for diagnostics of wide aperture optical elements

In the present paper modified Fizeau interferometer is discussed. The interferometer allows to diagnose plane and spherical optical elements with diameter of 10-300 mm. Accuracy of the measurements is lambda/10 (lambda=0.63 m). A new method of interference patterns reconstruction based on reference lines is proposed. This method allows to increase the reliability of interferometric pattern reconstruction and suppress the influence of incoming noise.