公开(公告)号：EP0690404A3

公开(公告)日：1998-05-27

申请号：EP95110309

申请日：1995-06-30

Applicant: SYMBOL TECHNOLOGIES INC

Inventor： LI YAJUN ,  DORAN ROBERT ,  BARILE JOHN

IPC: G06K7/015 ,  G06K7/10

CPC classification number: G06K7/10574

Abstract: An electro-optical scanning device reads indicia having parts of different light reflectivity, including bar codes and matrix arrays such as UPSCODES. The scanning device includes laser or light emitting diodes for emitting at least two light beams of the same or different wavelengths. The light beams may be visible to the human eye, and the beams are optically directed to form one or two scan lines to scan portions of a symbol. Dual photosensor(s) or a charge coupled device detects light reflected from the different portions of the symbol. The charge coupled device can be used to detect either reflected ambient light or the reflected visible light from the beams emitted by the diodes. The photosensors generate signals corresponding to the detected light which can be processed simultaneously. The device is particularly useful in reading two dimensional or more complex symbols. Methods for reading indicia are also described.