Stacked symbologies evolved as 1D codes -- Code 39 and Code 128 -- were stacked
in horizontal layers to create the multi-row symbologies, Code
49 and Code 16K, respectively.
followed in 1990 with added features that increased data capacity, improved data
density, and strengthened reading reliability by a scanner. These features
enabled decoding from scan paths that span multiple adjacent rows while
incorporating error detection and correcting techniques.
SuperCode, a stacked code that can break data into small
packets and create various shaped symbols, is also a member of this group of 2D
2D Stacked Symbologies examples
Code 49 was developed by David Allais in 1987 at the Intermec Corporation to
fill a need to pack a lot of information into a very small symbol. Labels can be
printed by standard printing technologies.
Code 16K, developed by Ted Williams in 1989 to provide a simple to print and
decode multiple row symbology, is mainly used in the health care industry.. (The
structure of 16K is based on Code 128). The code is a continuous,
variable-length symbology that can encode complete ASCII 128-character set.
PDF417 is a two-dimensional, multi-row symbology designed to be scanned by laser
scanners and linear CCD scanners and used to encode data files with hundreds or
thousands of characters in a laser scannable symbol. PDF417 is used in a
variety of applications, primarily transport, identification cards, and
SuperCode is a packet bar code symbology, a variant of a multi-row symbology.
There are precise rules for the horizontal placement of symbol characters in a
packet, but greater freedom in placing packets vertically and horizontally than
offered by a matrix of columns and rows in a multi-row symbology.