Patent ID: 6538252
Filing Date: 2003-03-25
Classification: D06H,G01B

Abstract:
A method for determining alignment of line formations of a web, said method comprising the steps of:providing a radiation source emitting radiation and a detector with numerous radiation sensors for sensing the radiation; reciprocating the radiation source and the detector together simultaneously transversely across a web; during the step of reciprocating, irradiating at least one measuring location of the web by the radiation source and measuring by short-time measurements within a microsecond range measured values, based on local radiation intensities of the at least one measuring location of the web, by the radiation sensors of the detector; communicating the measured values to a computer; computing from the measured values and from relative transverse positions of the radiation sensors to one another a local structural image of the at least one measuring location of the web, wherein the measured values are transformed into a sensor matrix of pixels based on a matrix arrangement of the sensors and a structural image of line formation is built from the measured values positioned adjacent to one another, and wherein a deviation of an alignment of line formations of the structural image of the web from a nominal structural image is determined.