SubscribeFor a packaging line to be efficient it needs to be producing for as much of the time as possible.
Any deviation from the required standard needs to be quickly identified and rectified to keep re-work costs to a minimum and to maximise line efficiency.
The key to this is successful monitoring of the line and there are a number of points at which this may take place from the primary filling operation all the way to a completed pallet.
Most products carry some form of human readable code: at the very least a code to trace the product and often information for customer use such as an expiry date. This may be applied in a number of ways, but checking will be carried out be either an Optical Character Validation (OCV) system which checks the code against a given "mask" or an Optical Character Recognition (OCR) system which compares the characters to a known character set.
Whichever system is employed, it relies on there being no ambiguity as regards the form and shape of each character. When it comes to the numerals, certain measures can be taken to improve the distinction between characters, namely
A "1" with a seraph (tick) at the top distinguishes it from an upper case "I" or lower case "L"
A "3" with a flat top is less likely to look like an "8" or a "B"
An open "4" is less likely to be confused with a "9"
Giving a "6" and a "9" a straight tail prevents them from migrating towards an "8"
Similarly for the alpha characters, a "J" needs to have a pronounced tail to prevent confusion with an "I" and "Q" also needs to be distinguished from an "O".
Such precautions usually ensure that a code is perfectly readable to the human eye, but may not go far enough to fully satisfy the requirements of an OCV or OCR system. For this reason, fonts specifically designed to be machine readable were designed.
OCR-A is the font that appears at the bottom of all cheques while OCR-B a less more generally used font that removes any confusion between characters when presented to the OCV or OCR system and for this reason is the font of favour for code reading applications.
Having identified that using the OCR-B font would improve code readability, the font needs to be produced by the coder. Here two technologies score particularly highly because of their quality of print: Hot Foil and Thermal Transfer. The engraved type used in a hot foil coder can be easily engraved with the OCR-B font and the quality of print is second to none.
A Thermal Transfer printer typically has a resolution of 305 dpi (12 dots per mm) and can equipped with the algorithm to product OCR-B characters, so permitting real time information to be produced in the same font.
In both cases attention needs to be paid to both the set up of the coder and to the selection of the appropriate grade of hot foil tape or thermal transfer ribbon to ensure that a clear crisp code is made.
Guaranteeing a perfect code and perfect code-read time after time makes this more that just a font more an essential tool in maximising line efficiency.
Example of a OCR-B font:
