Device for determining the surface shape of a shaft, which of a substantially flat article is reflected

摘要

The shape of a testpiece (P) including minute irregularities may be determined by mounting it on a movable support (S) and projecting a beam from an interferometer on to it. The reflected beam passes through a transparent slide with further reflection and the fringes enable the surface shape to be determined over a series of overlapping zones. It is essential that the incident light (FM) is orthogonal to the test piece (P) surface and this may be ensured by interposing an orientatable mirror (M1). The mirror is automatically guided to the correct position by an optical sensor (CO) which brings a luminous point (PO) representing the measuring beam (FM) to a reference location.