OBTAINING OF THE EXTENDED INTERFERENCE PATTERN IN CROSSED LIGHT-BEAMSWITH A BROAD-SPECTRUM

An extended achromatic interference pattern obtained in Mach-Zehnder a nd Michelson interferometers with small-angle refraction prisms placed in their arms is studied theoretically and experimentally. The restri ction imposed on the region of coherent interaction of beams by disper sion of the group velocity of radiation in prisms is studied. The fine ness of interference fringes is determined. The appearance of a dip in the visibility at the center of the interference pattern is found in the case of unequal arms of the interferometer.