Patent ID: 7170610

Claim:
Low-coherence interferometric apparatus for light-optical scanning of an object ( 18 ), by detecting the position of light-remitting sites ( 20 ) which are located along a scan path ( 27 ) running in a scan direction ( 28 ), with a low-coherence interferometer ( 6 ) comprising a low-coherent light source ( 7 ), a reference reflector ( 21 ) and a detector ( 25 ), wherein light emitted from the light source ( 7 ) is split by a beam divider ( 10 ) into two optical paths ( 11 , 12 ), and a first fraction of the light is irradiated as measurement light ( 16 ) onto the object and reflected at a light-remitting site ( 20 ) located at a variable scan position on the scan path ( 27 ), and a second fraction of the light is irradiated as reference light ( 22 ) onto the reference reflector ( 21 ) where it is reflected, the adjustable scan position is varied along the scan path ( 27 ) to perform a scan, and the measurement light ( 16 ) and the reference light ( 22 ) are combined at a beam junction ( 10 ) in such a manner that the resulting detection light ( 24 ), upon striking the detector, generates an interference signal which contains information about the reflection intensity of the measurement light relative to the respective scan position, characterized in that a variable wavelength selection device ( 30 ) is positioned in the light path of the detection light between the beam junction ( 10 ) and the detector ( 25 ), by which a wavelength-dependent separation of the detection light ( 24 ) is performed in such a manner that the detector ( 25 ) selectively receives preferably light with wavelengths which correspond to a predetermined sequence of wavenumbers k, and different sequences of wavenumbers k can be set for varying the scan position along the scan path ( 27 ).