Passing the Bar
Take steps to ensure your bar code products make the grade
By Stacey Wenzel
Bar code products continue to be a profitable niche. As a result, customers are becoming more demanding of the quality of the bar codes. According to Don Pistilli, OEM and national accounts sales manager for BST PROMARK, located in Elmhurst, Ill., research shows that this approach is a more effective means of evaluating the true quality of bar codes than hand, pen or laser scanners.
"Verifying the readability and quality of a bar code as it is printed is crucial," said Pistilli. He explained that one of the many standards for bar codes is set by the American National Standards Institute (ANSI). ANSI standards ensure the codes meet quality levels by assigning them grade levels.
Each code is evaluated for minimum reflectance, symbol contrast, edge determination, modulation, decodeability, defects and quiet zones. Each code is assigned an overall ANSI grade, per the ANSI specification. The grade levels follow the academic grading scale of A through F, with A meaning the code is superior and F meaning the code has failed. "ANSI sets stringent standards," Pistilli said. "The minimum level accepted by most customers is a C."
BST PROMARK manufactures bar code inspection programs as an option for their Pro Scan® Eagle video web inspection system. This option compares real-time printed codes against an acceptable (user-defined) quality standard.
Each code sampled is scanned, and as many as 400,000 pixels of data are evaluated against the established bar code standard. The program scans as many as 300 lines of each bar code sampled--analyzing up to 100 percent of the bar code.
The system, which is capable of monitoring UPC-A, UPC-E, EAN and Interleaved 2 of 5 codes printed either horizontally or vertically, provides immediate feedback to press operators on the percent of the bar code that is scannable, the grade level of the code (if ANSI standards are used), quiet zone readings, bar growth indicators and contrast percentage readings.