High-accuracy absolute distance metrology

Abstract not available

Measurements from a novel interferometer for EUVL mirror substrates

A previously reported interferometer without intermediate optics is used to perform measurements on an aspherical extreme ultraviolet lithography mirror substrate. Acousto-optic modulation based phase shifting is used together with a novel phase retrieval algorithm to retrieve the phase distribution from our interferograms. The phase...

Michelson wide-field stellar interferometry: Principles and experimental verification

A new interferometric technique for Michelson wide-field interferometry is presented that consists of a Michelson pupil-plane combination scheme in which a wide field of view can be achieved in one shot. This technique uses a stair-shaped mirror in the intermediate image plane of each telescope in the array, allowing for simultaneous correction...

Absolute Heterodyne Interferometer for Strongly Aspherical Mirrors

For the past thirty years, microchips have doubled in complexity every two years. This increasing complexity required that the size of the structures written on silicon halve at the same rate. A fundamentally limiting factor to the size of microchip structures is the wavelength of the lithographic projection processes used in their manufacture....