title: Measurement of two-dimensional small angle deviation with a prism interferometer.
abstract: A new technique for the measurement of two-dimensional small angular deviation is presented. A compound prism, which effectively produces a combination of two right-angled prisms in orthogonal directions, and plane reference surfaces have been utilized for the measurement of the orthogonal components of the angular tilt of an incident plane wavefront. Each orthogonal component of the angular tilt is separately measured from the angular rotation of the resultant wedge fringes between two plane wavefronts generated due to splitting of the incident plane wavefront by the corresponding set of right-angled prism and plane reference surface. The technique is shown to have high sensitivity for the measurement of small angle deviation. A monolithic prism interferometer, which is practically insensitive to vibration, is also proposed. Results obtained for the measurement of a known tilt angle are presented.
authors.affiliation: Raja Ramanna Centre for Advanced Technology, Department of Atomic Energy, Government of India, Indore-452013, India. schat@cat.ernet.in
authors.forename: Sanjib
authors.initials: S
authors.lastname: Chatterjee
authors.forename: Y Pavan
authors.initials: YP
authors.lastname: Kumar