Rockwell Automation 2755 High Performance VLD Scanner - Manual (Page 54)

Glossary G–6
Resolution
1) The measure of the ability of a lens, a photographic material or a
photographic system to distinguish detail under certain specific
conditions. 2) The dimension of the smallest element which can be
printed employing a particular technique. 3) The narrowest element
dimension which can be distinguished by a particular reading device.
Retroflective
Characteristics of material causing it to reflect light back to its
source regardless of angle of incidence.
Retroflector
A reflector, specially constructed, which reflects energy back to the
source from which it came.
Reverse Image
A symbol in which the normal dark areas are represented in the light
areas.
Scan
The search for a symbol or marks which are to be optically
recognized.
Scan Area
The area intended to contain a bar code symbol.
Scanner
A device that optically scans bar code symbols and converts the
optical information into digital or analog form and sends it to a
decoder.
Self-checking
A bar code or symbol using a checking algorithm which can be
applied to each character to guard against undetected errors. Codes
that are not self-checking may employ a check digit or other
redundancy in addition to the data message.
Skew
Rotation about the X axis. Rotational deviation from correct
horizontal and vertical orientation may apply to a single character,
line or encoded item.
Space
The lighter element of a bar code formed by the background between
bars.
Special Symbol/Character
In a character set, a character that is neither a numeral, letter, or a
blank: for example, @ $ % & *.