Hold At An Angle - Symbol LS 400 series Product Reference Manual

L S 4 0 0 0
Aiming

Hold at an angle

Do not hold the scanner directly over the bar code. Laser light
reflecting directly back into the scanner from the bar code is known
as specular reflection. This strong light can "blind" the scanner and
make decoding difficult. The area where specular reflection occurs
is known as a "dead zone".
You can tilt the scanner up to 65 ° forward or back and achieve a
successful decode. Simple practice quickly shows what tolerances to
work within.
Successful
Successful
Possible Specular
Scanning Scanning
Reflection
65 65
4
4