Some Investigations in Talbot Interferometry for Collimation Testing

We have proposed new type of self referncing dual field gratings based on ares of cireles and used them in Tathot in interferometer for collimation tesling. The performance of these gratings is compared with dual field linear gratings. The difference in sensitivity of art: gratings is verified by simulatcd moire fringes. The use of a single self referencing grating with a right angle prism retro reflector in a Talbot interferometer is also discussed.