Light pick-up device

Claim 1

In a scanning device for point-by-point and line-by-line opto-electronic scanning of an information bearing master mounted on a flat bed carrier for supporting said master, said device including means for projecting a scanning light beam along a line on the master, which light beam is modulated by the information of the master to form mudulated light, a light pickup device for collecting the modulated light from the scanned master and opto-electronic transducer means for converting said collected modulated light into image signals, said light pickup device consisting of an elongated hollow body having an inside reflective surface, a slot-shaped light entrance opening extending parallel and at least the length of the line and facing the master for receiving the modulated light, and said pickup device having a light pickup area for receiving the modulated light collected by said hollow body, the improvement comprising: (a) the light pickup area including at least one light pickup opening having a slot shape of substantially the length of the entrance opening and extending parallel thereto, a slot-shaped light entrance face of an optical-shaped converter having a light exit face being coupled to said opto-electronic transducer, said light entrance face having an aperture angle β and filling the light pickup opening; (b) the reflective surface of the hollow body lying opposite the light entrance face at least in the area covered by the aperture angle β of the light entrance face being a diffused reflector and the reflective surface of the hollow body lying adjacent the light entrance face being a second reflector; (c) said diffused reflector being shaped in such a manner and being aligned to the light entrance face so that a large portion of the modulated light is converted by said diffused reflector into diffused light and reflected onto the light entrance face; (d) said diffused reflector and said second reflector being disposed to one another in such a manner that the portion of diffused light not reflected onto the light entrance face and the portion of modulated light striking the second reflector are reflected by said second reflector to the diffused reflector and converted into diffused light; and (e) the light pickup opening being positioned in the hollow body relative to the light entrance opening so that the modulated light does not directly strike on the light entrance face but rather is converted into diffused light by said diffused reflector before being received by the light entrance face.