Patent ID: 6931149

Claim:
An optical inspection apparatus ( 1 ) for internal surveying of a pipeline ( 2 ) for transporting fluid ( 3 ), said apparatus comprising; an energy supply unit ( 18 ); a light source means ( 4 ) adapted to form one or more fan shaped beams of light ( 5 ) illuminating a line (L) of an interior surface part ( 9 ) of said pipeline ( 2 ); optical receiving means ( 6 ) positioned outside a plane formed by said fan shaped beams ( 5 ) and arranged to have in its field of view ( 7 ) the line (L) formed on the internal wall of the pipeline ( 2 ) by said fan shaped beam ( 5 ); said optical receiving means ( 6 ) adapted to form a plurality of two-dimensional indexed images ( 20 k ), said index k representing a running image number, each of said images ( 20 ) comprising intensity data for a predetermined number of pixels in each of a predetermined number of lines (M) of said image ( 20 ); a data processing unit ( 100 ) including an image analyzer module ( 110 ) with a surface depth profile analyzer module ( 120 ), said depth profile analyzer module ( 120 ) adapted for extracting a depth profile of said surface ( 9 ) from said recorded images ( 20 ) by analysing maxima (m) along said lines (M) for obtaining curves (N) representing said line (L) by positions p(x) of said maxima (m) for each image ( 20 ) whereby the positions p(x) of said maxima (m) in the image represents a surface profile (N); a first storage means ( 160 ) for storing of said curves/surface profiles (N).