Reader unit for scanning a document, such as a barcode, coded in binary format, with the lens arrangement such that the optical resolution is the same over the whole width of the scanning unit

摘要

A scanning opening (3) contains a contact surface (2), while a lens (7) is contained within a lens carrier (6) with an associated light source. The lens is in the form of a multi-element lens and can be moved along the scanning opening at a constant distance adapted to the focal length of the lens.