Barcode scanner having a dead zone reducing system and a multifocal length collector

摘要: An optical system for use in a scanning reading symbols. The includes head containing the system. comprises light source generating beam of light. A scanner is provided directing towards symbol and across symbol. Further, accordance with present invention, dead zone-reducing lengthening path length between to reduce zone exterior head. collector collects reflected from directs it detector. at least two sectors each having different focal lengths. detector detects variable intensity returning portion laser over field view, generates an electrical signal indicative detected intensity.