PostBar and Royal Mail
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the error and one to correct for it, a given security level can support half the
number of misdecodes that it can of undecoded words.
Print Data Field is not offered due to the large amount of data that can be
encoded.
PostBar and RoyalMailPostBar and Royal Mail bar codes, like POSTNET, are used for mai ling
applications. However, these bar codes can encode full addresse so n labels.
These bar codes are similar to POSTNET in terms of bar space and width, but
have four different types of bars (Full Height, Ascender, Descender, and
Tracker), whereas POSTNET only has two bar types (Tall and Short).
The Royal Mail symbology converts alphanumeric characters into patterns of
four bars, using combinations of Full Height, Ascender, Descender, and
Trackers. It also adds start and stop bar codes as well as a check digit.
PostBar allows you complete flexibility to specify the individual bar types that
comprise the signal. For PostBar, you are responsible for encoding the
address, adding the start and stop codes, and supplying the appropriate
check digit.
Quiet Zone
Thebar code structure requires a completely blank quiet zone which is a 2mm
border on each side of the bar code.
Start/Stop Code
The start and stop bars identify the orientation of the bar code.
Data Field
For PostBar, a variable length data field of digits “0” through “3” are allowed to
represent the bars: Full Height (0), Ascender (1), Descen der (2), and Tracker
(3). For Royal Mail, the data is restricted to alphanumeric characters “A”
through “Z” and “0” through “9”.
Each bar
width
is equal, and must be .020-inch ±.005-inch. Horizontal
spacing between bars (pitch) must be 22 bars ±2 bars per inch over any
0.50-inch portion of the bar code. The height of the bars (Full Height) has a
maximum of 0.230 inches and a minimum of 0.165 inches,
Check Digit
For PostBar, you are responsible for encoding and check digit. For Royal
Mail, a modulo-6 check digit is inserted at the end of the data fiel d.