Patent ID: 6040901
Filing Date: 2000-03-21
Classification: G07D

Abstract:
An apparatus for optical detection of sheet material, for example bank notes, havinga detection device (40, 41) for detecting the light of an area (B) of the sheet material (10) incident from the direction of an optical detector axis (A.sub.1) and emitted by the sheet material (10) in the direction of an optical sheet material axis (A.sub.2, A'.sub.2),an illumination device (30, 31) for illuminating at least the area (B) of the sheet material (10),characterized in thata reflection device (50) with reflectors (51, 52) is provided for deflecting the light emitted by the area (B) of the sheet material (10) in the direction of the sheet material axis in the direction of the detector axis,an adjusting device is provided for changing the position of at least two reflectors (51, 52) for fixing the position of the area (B) on the sheet material (10) relative to the detection device (40, 41), andthe reflectors (51, 52) are disposed so that the length (L) of the optical path of the emitted light from the sheet material (10) to the detector device (40, 41) is independent of the position of the area (B) on the sheet material.