INTERFEROMETRIC MEASURING ARRANGEMENT

摘要

The invention relates to a measuring arrangement (10) for interferometrically determining a shape of a surface (12) of a device under test (14). Said measuring arrangement (10) comprises a light source (16) for supplying an input wave (18) as well as a diffractive optical element (24). The diffractive optical element (24) is suitably designed to generate, from the input wave (18) by diffraction, a test wave (26) which is directed to the device under test (14) and which has a wavefront that is at least partially adjusted to an expected shape of the optical surface (12), and a reference wave (28). The measuring arrangement (10) further comprises a reflective optical element (30) for reflecting the reference wave (28) as well as a capturing device (36) for capturing an interferogram generated by superposing the test wave (26), upon its interaction with the device under test (14), and the reflected reference wave (28) following another diffraction of the two waves on the diffractive optical element (24) in a capturing plane (48). The invention further relates to a corresponding method for determining the surface shape of a device under test (14).