Patent ID: 6111644
Filing Date: 2000-08-29
Classification: G01J

Abstract:
A Michelson type optical interferometer having an optical axis for receiving incoming radiation and analyzing and determining the direction with respect to said optical axis of coherent radiation from a source located effectively at infinity without requiring movement of the interferometer comprising:means including a beam splitter for dividing said incoming radiation into not more than two beams,means for introducing a phase delay between said beams large enough to discriminate between temporally coherent and incoherent sources,means for introducing a shift between said beams large enough to distinguish between spatially coherent and incoherent sources,means for introducing a lead between said beams sufficient to produce a distinguishable interference pattern for a coherent source only,said interferometer having no shear or tilt;means for defining a plane of observation positioned on said optical axis, andmeans for recombining said beams to create a fringe ring interference pattern from said source of coherent radiation in said plane of observation, whereby the position of said fringe pattern in said plane of observation with respect to said optical axis is a function of the direction of said coherent source with respect to the said optical axis.