Performance of a speckle interferometer

An interferometer system for use at the 2.34 meter Vainu Bappu Telescope (VBT), situated at Vainu Bappu Observatory (VBO), Kavalur, to obtain speckle-grams of astronomical objects in the visible wavelength, has been developed. Laboratory tests of resultant intensity distributions due to a point source, with phase modulation screens, as well as the images obtained using this interferometer at the cassegrain end of the said telescope are discussed.