New 2-D Bar Code
DotCode-128 accepts a wide variety of printer options and printing media.
By Anastasia Thrift
DotCode can be represented as dark on light background or light on dark background.
A new method of serializing pharmaceuticals has been accepted by an automatic identification and tracking trade group. The Association for Automatic Identification and Mobility (AIM Global; Warrendale, PA) announced that it will accept DotCode-128, a new 2-D bar code symbology that offers machine readability with ink-jet technology.
DotCode-128, also called DotCode, is made up of an optically read grid that, unlike other bar codes, does not need a line of connected dots to constitute a full code. This allows for greater growth and shrinkage of encoded dots. As opposed to its predecessor, Code 128, DotCode can carry supply-chain messages of up to 400 characters.
“The real advantage of DotCode128 is that it’s easy to print,” says Bert Moore, director of communications and media relations, AIM Global. He adds that along with its “ease of printing and large dimensional tolerances,” DotCode requires no royalty fees for use.
Printing 2-D codes in commonly used Data Matrix format necessitates contiguous areas of light or dark patterns. Without a need to touch, the small dots of DotCode can be reproduced by a greater number of printers than Data Matrix can encode, according to Moore.
Global supply-chain standards organization GS1 has yet to adopt this technology. Therefore, Moore says, DotCode remains best suited to internal tracking or trading-partner agreements.
“It could be used to encode batch or lot, best-by [expiration date], etc., where it’s currently not possible to do so,” Moore says. “DotCode-128 doesn’t currently fit into GS1 standards since the symbology is still developing additional features and benefits.”
DotCode continues to evolve. “It has a lot of shape and strong technology, as well as working demonstrations, already behind it,” developer Andy Longacre, PhD, W.F. Allyn Research Fellow with Hand Held Products (Skaneateles Falls, NY), says. “It’s like soft clay.”
“Early EPC work promoted the concept that every retail item could be individually serialized, but surely RFID tags—even a ‘penny’ tag—cannot economically mark a can of corn,” Longacre says. “One of my colleagues noted that only high-speed inkjets or laser markers can presently serve this sort of use, like those expiration dates printed on soda cans.”
Longacre tried to adapt image-reading technologies to process ink-jet printing, by using optical code recognition on such printed characters. Because ink-jet printing can cause potentially significant geometric distortion, gaps occur. The company began investigating whether a new symbology could “remain robust and, especially, misread-free,” while potentially displaying such distortions, Longacre says.
“Through late 2006 I experimented with a few ideas, and in early 2007 I was encouraged to push through with what has become DotCode,” Longacre says. “We openly announced DotCode in June 2007 to establish its critical underlying technologies in the public domain.”
“Originally conceived as just a small-capacity low-height [ribbon] symbology, indeed we’re now finding it performs well for larger messages and sizes, too,” he adds.
To accommodate the new printing method, packagers would need 2-D image-based reading equipment and ink-jet printers. DotCode also requires a 20% printing-area increase over 2-D symbologies such as Data Matrix, but about half the area of stacked symbologies, and even a smaller fraction of linear symbologies like Code 128. Supporters of DotCode insist that any additional package space or new equipment needed is justified by DotCode’s increased efficiency.
“None of those others are easily well printed with varying data at full production line speeds,” Longacre says. “High-speed inkjets currently print human-readable characters using internal pattern-generating routines. They could surely also integrate a DotCode encoder for producing machine-readable marks.”
Benefits include offering a wide range of rectangular to nearly square symbol sizes, and quick printing of real-time data, such as expiration date, lot number, or serial number. Optical readers can read DotCode omnidirectionally. Because it is a nonproprietary technology, no royalties are owed to the creator.