Is your bar code reader illiterate? It might seem that way to some control and automation engineers, not to mention supermarket shoppers. However, many readers simply bog down when struggling to read labels that aren't lined up straight.

To lessen this traditional problem, Rockwell Automation recently introduced its Allen-Bradley StrataScan Bar Code Reader, which uses holographic technology to produce an omnidirectional scan pattern to interpret random-label applications.

"In traditional line scanning applications, bar code labels must be aligned in a consistent orientation to ensure good reads by the bar code scanner," says Patty Roberts, Allen-Bradley Automatic Identification Products' marketing programs manager. "With Strata-Scan, labels can be read in virtually any orientation, and at varying depths of field—dramatically increasing application throughput and productivity."

StrataScan uses holographic lens technology to create multiple scan lines at different layers for a depth of field of up to 42 inches. Combined with a high-speed processor, StrataScan has read at speeds up to 300 ft/min.

"Traditional scanners have defined depths, so the significant innovation here is that holography allows this new bar code scanner to read at multiple depths. This method may also be less expensive than trying to solve depth of field problems using a camera-based system," says Dan Mullen, vice president of technology for AIM USA, the Automatic Data Collection and Identification Manufacturers Association (Pittsburgh, Pa.). "For industrial users of many conveyor belt-based applications, this new scanner could mean they'll be able to maintain efficiency without having to be quite as precise when lining up items in their systems." Mr. Mullen adds that StrataScan could likely be used in shipping, receiving, warehouse, and other distribution and tracking applications.

StrataScan's only moving part is a single holographic disk that replaces the focusing lens, light collection lens, and the rotating or oscillating mirror used in standard laser scanners. As StrataScan's holographic disk rotates, the lenses on both the outbound and return paths focus up to five visible laser diodes to generate up to 105 scan lines per rotation. At 4,200 rpm, up to 7,300 scans lines are generated, which enhances scanning performance.

Unlike other omnidirectional readers, which usually have a cone shaped read area, StrataScan repeats the same scan pattern over multiple focal lengths. This produces a consistent read width from the top to the bottom of the read area. When a wider read area is necessary, users can connect other readers in a master/slave configuration to achieve greater read widths.

StrataScan can also decode the following symbologies: UPC-A, UPC-E, EAN 8, EAN 13, Code 39, Interleaved 2 of 5, Code 128, Code 93, Jan 8, Jan 13, and Codabar. With a starting price below $8,000, StrataScan has a port for an optional integral handheld scanner and connector for an I/O interface box with one input, one output, and a trigger port for a package detector.

For more information, visit www.controleng.com/info.