Rockwell Automation 2755 High Performance VLD Scanner - Manual (Page 52)

Glossary G–4
Mis-encodation
When the characters which were to be represented in symbol form
are not correctly encoded. Example: desired number is 1, 2, 3, 4; the
encoded number is 1, 2, 5, 4.
Misread
A condition which occurs when the data output of a decoder does not
agree with the encoded data presented. See substitution error.
Moving Beam Scanner
A device which dynamically searches for a bar code pattern by
sweeping a moving optical beam through a field of view.
Nanometer
Unit of measure used to define the wavelength of light. 10
-9 meters.
No-read
The absence of data at the scanner output after an attempted scan due
to no code, defective code, scanner failure or operator error.
Nominal Size
The standard size for a bar code symbol. Most codes can be used
over a range of magnifications from 0.80 to 1.20, nominal.
Numeric
A machine vocabulary that includes only the numbers as contrasted
to alphanumeric which includes both letters and numerals.
Opacity
1) The property of paper that minimizes the show through of printing
from the back side or the next sheet. 2) The ratio of the paper
reflectance with a black backing to the paper reflectance with a white
backing.
Optical Throw
The distance from the face of the scanner to the beginning of the
depth of field.
Orientation
The alignment of bars and spaces to the scanner. Often referred to as
vertical (ladder) or horizontal (picket fence).
Paper Noise
A term used to describe the reflective effect of the laser beam on
paper (or any other surface) where microstructure causes variability
not attributed to the bars and spaces. This effect can result in
reduced readability of labels and decreased read ranges.
Permanent Code
A code which is indefinitely reused in a bar code application.