Dead Zone - Allen-Bradley 2-D User Manual

Dead Zone

When scanning a 1-D bar code, there is only a small specular dead
zone to avoid (+2_ from the direct laser beam). The specular dead
zone is larger when scanning PDF417 (+9_ from the direct laser
beam). At the same time, the scanner is not effective if its beam hits
the bar code's surface at an angle greater than 30_ from normal to
that surface.
1. Successful Scanning
Tilted 0_ – 30_ back from surface
0_ – 30_
You can also scan successfully by tilting the scanner forward from
parallel about 20_ to 50_ toward the scanning surface.
Operating the Scanner
Scan Beam
Normal
Scan Beam
Right Angle
Bar Code
Angles for Good Decodes
2. Successful Scanning
Tilted 20_ – 50_ forward toward surface
20_ – 50_
3–7
Publication 2755-6.4