Vision sensor checks codes fast

A new self contained camera sensor is able to check the print quality of data and lot codes on packaging at up to 285 frame per second. The DCI 10, (the letters stand for Date Code Inspection) device from Erwin Sick is able to work so fast because it does not actually read the codes, but instead compares the number of dark pixels in a search field against a taught in example with applied tolerances. It does this by combining a 320 x 320 pixel 2D image recorder with a high speed signal processor. The device comes with an integral ring of 15 focussed illuminating green LEDs around the periphery of the lens, so no external light is required. Target fields are 20 x 20mm at a nominal distance of 70mm, and it has four outputs. These are: detected code within tolerance range, outside tolerance range, near to or below lower tolerance limit, and near to or above upper tolerance limit. It can thus be used to warn of deteriorating print quality, perhaps due to too little or too much ink, before the printed codes deteriorate to such an extent that production has to be stopped. Under new European Union rules coming into force on January 1st 2005, all companies involved in any stage of food production must be able to provide full traceability of products, taken from suppliers and provided to customers. Ensuring that legible lot numbers are correctly printed on products and packaging before they are shipped is thus going to become a mandatory requirement. This requirement is in addition to existing legislation requiring that most food carries a 'best before' or 'use-by' date. Price is £1258. Erwin Sick