H. Miyazaki et al., AUTOFOCUSSING TYPE BARCODE READER OBR-70-7AF WITH ADVANCED BEAM FORMING AND DECODING TECHNIQUES - OMNIDIRECTIONAL READING IN GREAT DEPTH OFFIELD, NEC research & development, 34(2), 1993, pp. 239-247
Until now, low aspect ratio barcode symbols with high barcode density
have been used in application of hand held type scanners. The NEC LASE
R SCANNER OBR-70-7AF - the autofocussing type barcode reader - has bee
n developed for applications of fixed type scanners aiming for manpowe
r saving by allowing them to be read omnidirectionally and in great de
pth of field. Reconstruction of fragmentary data obtained in some part
ial scannings, instead of only validation of all bars and spaces data
in one scanning, is carried out with a new decoding technique. Great d
epth of field is obtained with a new autofocussing technique which pos
itions the beam waist along the laser beam optical axis with keeping i
ts diameter unchanged.