Optical test device

An optical test device for testing flat test objects, comprising:

• a holder for the test object and
• at least two optical sensors for detecting the three-dimensional surface topography of the test object, wherein:
• the holder is formed at least in sections as test standard and is disposed relative to the sensors in such a way that the sensors scan the test object from opposite sides and, during the detecting of the test object, also detect the holder as test standard at least in sections,
• the holder comprises two plate-shaped individual parts, each with a window-shaped recess for the receiving of the test object in a reference plane, which are formed as test standard surfaces at their mutually facing surfaces, and
• the individual parts are connected to each other in the reference plane offset relative to each other in such a way that test normal surfaces of the one individual part can be or are scanned by one of the sensors through the recess in the other individual part.