Character Recognition and Product Identification

Supplier: Industrial Photonics
29 May, 2008

Smart cameras can be utilised to improve a company’s quality control or achieve cost savings by using common equipment to pack or label the goods on multiple production lines.

Industrial Photonics have developed specific inspection systems for optical character recognition (OCR), based on PPT Vision and VPM softare.

The IP Code Check system utilise smart cameras that can be mounted after an ink jet printer or labeller to determine that the date code or “use by” date is present and legible for that product. It can also verify that every product produced has the right label applied throughout that production run. The system can then automatically reject that individual faulty labelled product or stop the line for consecutive defects. This automatic inspection stops incorrectly labelled product from getting out to the market place and reduces re-work by flagging set up faults before too many incorrectly labelled are produced.

The set up is simplified for the operators, they just scan the barcode of the product and the smart camera automatically sets up all its own parameters. The Q:Check Bar Code will then reject any other product until a new production run is selected.

This same OCR functionality can be used to identify different products coming down a common production line. The smart cameras can identify the labels, ink jet codes, shape or artwork of the products and then communicate directly to a barcode printer, palletiser or PLC. For example, cartons are identified, tracked and directed to a series of conveyors. A single palletiser can then pack multiple lines dropping capital costs and reducing floor space.

The identifier could be for example an inkjet code printed in association with the application of the date code like an A, B, C for lines number one, two and three. The robust software can recognize most fonts with a high degree of accuracy, even on high-speed production and assembly lines with variable quality ink jet codes. Even human applied codes can be recognized by the smart camera. The software is capable to distinguish different hand writing and has an inbuilt teach function to simplify setup .

Whilst these applications refer to rather simple markings on goods, the 2D and data matrix barcodes contains much more information then a standard barcode but they can not be decoded by a normal barcode scanner. The IP Code Check inspection system can scan and read the information of the matrix codes, which feature square or dot-shaped modules arranged on a grid pattern.

The system checks the presence of the code, the size of the dots, the number of dots (vertical and horizontal) and the size and length of the characters. It also picks up splashing of ink around the barcode and ignores it. The smart camera then automatically talks to the common palletiser, barcode printer, robot or a PLC to report what kind of product is being processed on the production line.