An optical device for sensing a surface profile of an object surface of an object by means of interferometric distance measurement, including a beam splitter for splitting a light beam of a light source into first and second sub-beams, a beam divider for dividing each sub-beam into a reference and a measuring beam, a mirror for reflecting the two reference beams, wherein each measuring beam is directed onto a measuring area on the object surface for reflection and after reflection is directed as object beam to the beam divider, each reference beam reflected by the mirror and directed as mirror beam to the beam divider, the object and mirror beams each interfere and are each fed as an evaluation beam to a detector unit for evaluation. Further include a light source for generating a monochromatic light beam, a detector unit, a signal evaluation unit and for determining the surface profile.