Smaller World (Bar Code Inspection)
The 2-D Reduced Space Symbology (RSS) bar code is beginning to crack mainstream applications. See below for a UPC update.
by Susan Friedman, Editor
A FRESH down-sizing initiative in the bar code arena may require converters to broaden approaches to bar code printing and inspection. New Reduced Space Symbology (RSS) bar codes, developed to address space-constrained applications, are smaller than Universal Product Codes (UPC), yet allow deeper levels of product identification.
On meat packages and loose produce, RSS facilitates enhanced food safety and faster, more accurate checkouts. RSS codes on meat, for instance, can carry brand, cut, sell-by dates, or case information. On produce, RSS can eliminate the need to manually key a price look-up number, better ensuring the consumer is charged the right price. Initial trials in pharmaceutical applications show RSS's potential to reduce medication errors in unit-of-use and unit dose items.
According to Steve Arens, director, food and beverage, at the Uniform Code Council, preliminary application guidelines for labels, symbol size, and data content for both meat and produce will be available soon, so retailers/wholesalers can begin working with equipment suppliers on implementation, and with product suppliers on label requirements. The majority of initial RSS applications may be produced with stand-alone bar code printers, but if you're thinking you won't encounter this symbology on-press anytime soon, think again (see sidebar below).
Vision quest
Once RSS does begin popping up on-press more frequently, how should converters approach quality control? Frank Sharkey, senior project manager at the Uniform Code Council, explains all linear symbology print quality guidelines, including those for RSS, are defined in ISO/IEC 16416. Verification requirements are outlined in ISO/IEC15426-1.
Before converters can verify, however, they've got to get these little codes down on the substrate first. "The biggest pitfall with most of these new codes is that they are smaller and denser, and therefore leave less room for error," points out Elizabeth Urvan, senior sales consultant, Stratix. "Some printing challenges will include ink gain/loss, missing sections of the bar code, and overall uniformity in the image of the bar code. In some cases converters may have to print more slowly then they could to produce standard linear bar codes."
Sharkey notes normal quality practices should ensure accurate reproduction of RSS, though its smallest X dimension—6.7 mil—is a departure from the 10.4 mil X dimension typical for UPC.
When it comes to inspection and verification, converters may have to adapt current systems or invest in a new approach altogether. "Unlike standard linear bar codes, new codes such as RSS require equipment that can evaluate the entire code from top to bottom," notes Urvan. "In most cases, that means new verifiers with rastoring laser scanners or imagers that can evaluate the entire bar code."
At Webscan, President Glenn Spitz says the laser-based TruCheck verification system is already able to handle RSS codes by providing automatic scanning across and down, eliminating inaccuracies caused by sweeping hand motions.
PC Industries, reports Sales Manager Doug Radant, can accomplish RSS verification by integrating elements of its camera-based VIPER inspection system and its laser-based CODE-TRACKER CT400 bar code verifier, gleaning the VIPER's camera capability to read the 2-D code, and the CT400's ANSI grading software.
A CCD camera-based system can indeed inspect RSS codes, says Iggy Manning, president of Geiger Vision Systems, as long as the resolution meets inspection criteria, which can be achieved with a higher pixel density per square inch. Geiger's higher resolution camera has a 1,300 x 1,000 pixel array.
Advanced Vision Technologies (AVT)'s PRINT VISION web inspection systems offer bar code add-on modules such as AVT ABCv, which provides ANSI verification, and checks modulation, quality, contrast, and decodeability. "It is essential for an automatic print defect detection system to be a scalable, open platform system allowing various application modules to be added according to the printing application at hand," says AVT Marketing Manager Orit Eyal. "If smaller bar codes are becoming of popular use, smart/open architecture inspection systems will be able to implement new algorithms which will support the verification of such."
What's up with UPC?
More than ever, the rules of the Universal Product Code (UPC) bar code quality game must be followed, and that means keeping up with a shifting game board.
"Because every major retailer today has a system of fines in place for non-conforming or non-scanning bar codes, the potential risk—and cost—to the converter can be quite large," states John Thome, vice president, marketing, BST PRO MARK.
"Pressure from retail chains means bar code verification systems must be able to guarantee B grade or better bar codes," seconds Doug Radant, sales manager at PC Industries. "Many bar code verifiers simply verify that a bar code is readable, but that could be D-grade readability," he explains. Heightened concern about compliance to this level of quality has both rekindled interest in established verification equipment and spurred the development of new technologies.
PC Industries' laser-based CODE-TRACKER CT400 online ANSI bar code verifier has been available for nearly five years, but according to Radant, "is now coming into its own because of demands of retailers." The CODE-TRACKER provides 100 percent verification at top press speeds, and full ANSI/ISO inspection and documentation.
At PRINT 01, BST PRO MARK introduced the LS300 laser bar code verification system, which uses a laser scanning head to perform 100-percent ISO/ANSI inspection on static or sequential bar codes, at normal press speeds. The LS300 provides a real-time graphic display of bar code quality, and allows continuous quality monitoring. When bar code quality degrades, the system helps identify the corrective action required, and provides complete written documentation on each roll or job.
So not only are the bar code stakes now higher, but rules of verification have changed, albeit ever-so-slightly. The ISO 15416 Bar Code Print Quality Test Specification for Linear Symbols, published to replace ANSI X3.182 last summer, could make a converters' current bar code inspection approach obsolete.
"Under ISO 15416, camera-based bar code verification systems no longer meet the ISO/ANSI requirement," contends Thome. "That does not mean camera- based systems won't work, but it does mean that converters who are required to provide ISO/ANSI-compliant bar codes must use a laser-based system."
"While we speak of the ANSI spec since that is the terminology most converters are familiar with, we still comply with ISO 15416, which is an international version of the ANSI spec," explains Glenn Spitz, president of Webscan.
Spitz adds CCD camera-based inspection systems may have a hard time complying with ISO because of its requirements for measuring a specific wavelength of light at a specific spot size, to ensure the measurement medium correlates closely to scanning equipment at the point of sale or end use.
Webscan's TruCheck system complies with a fixed-wavelength laser and a 6-mil spot size. Other devices which require contact to the sample, such as wands, achieve ISO compliance with LED light sources and filters.
A certain degree of automation is integral to ensuring bar code parameters are met, and different approaches to this capability are evident in current online and off-line verification offerings.
According to Spitz, Webscan's off-line TruCheck unit was developed in response to the company's online customers, who saw the reliability of online measurements, but wanted to eliminate wands and guns in applications that did not warrant online equipment. Its laser automatically moves from top to bottom through a bar code, collecting the 10 ANSI-recommended scans. Operators place the sample under the laser and touch a button, allowing automatic control for consistent results.
"Changes in bar code quality can and are caused by plate wear, impression change, viscosity change, and even register shift," states Thome, making a case for managing the verification process online versus "checking a bar code off-line now and then during the run." He maintains converters who want to minimize risk of retailer fines must implement a process control system on the press.
