A hand-held bar code reader includes one or more photosensor arrays which provide a plurality of image sensor portions arranged for receiving images of a bar code through a plurality of selectively usable paths of 5 different focal lengths which are defined by a passive optical system. A distance measuring...http://www.google.co.uk/patents/US5640001?utm_source=gb-gplus-sharePatent US5640001 - Hand-held instant bar code reader having automatic focus control for operation over a range of distances
