Optical character recognition (OCR) is a vision system tool that is widely used in the packaging industry. Like bar code technology, OCR is a data-capture methodology. Its primary advantage is that it encodes information in a format that is both machine- and human-readable, while bar codes and 2-D symbols are only machine-readable.

OCR turns printed text characters from a digital image into a string of characters that can be decoded by the system, and then moved through subsequent steps in the production process as defined by the control software.

The simplest and most reliable method for optical character recognition relies on specific OCR fonts and templates that are designed for these applications (see figure 1). However, machine vision’s powerful functionality incorporates teachable OCR systems that can be “trained” to recognize characters in a user-defined font—a useful feature given the wide array of available printing technologies and the range of printed characters produced by them.

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