Patent ID: 6836333
Filing Date: 2004-12-28
Classification: G01J

Abstract:
An interferometric optical block having three planar nominally parallel surfaces with the two outer surfaces adapted to act as beam reflectors for internal light and the third surface in operation acting as a beam splitter and beam combiner, the optical block having an input portion by means of which an input beam of light to be analysed can be input so as partially to pass through said third surface to be internally reflected by one of said outer reflectors, and partially to be reflected by said third surface so as then to be internally reflected by the other of said outer reflectors whereby light internally reflected by said outer reflectors is combined at said third surface to produce an exit beam, and wherein said outer surfaces have an inclination with respect to one another and are asymmetric with respect to said third surface so as to generate in the exit beam a linear fringe field distributed about the zero-order fringe.