Lesevorrichtung fuer optisch erkennbare Zeichen

摘要

A reader mechanism for optically discernible characters, especially characters associated with an article and applied thereat or thereto and which can be located within a predetermined depth of focus region about a reference plane and can be scanned by means of a light spot, wherein there is also present a photoelectrical receiver which takes-up a portion of the light reflected back from the character and delivers an electrical signal corresponding to the incident light current. The invention provides for a collecting lens arranged between the reference plane and the receiver. A diaphragm arranged at the focal plane of the collecting lens confronting the receiver at the region of the light current extending to the receiver. The diaphragm is provided with an opening dimensioned such that a light beam emanating from the forwardmost situated plane of the depth of focus region and directed towards the receiver at least completely fills-out the diaphragm opening in the transverse direction.