This functionality extends to serialised labels as any faulty labels detected are re-printed ensuring serial number sequences are maintained. For more information on barcode standards, follow this link to the GS1 Website. When a faulty label is detected, the printer rewinds and overprints that label before re-printing it, ensuring no loss of sequential data.
Blemish detection with variable tolerances and zoned areas allows the detection of print defects such as ribbon crease and printhead wear. Flexo Tools resolve flexo specific printing issues. Novice flexo operators will develop images ready for flexo, while experienced retouchers will appreciate how the flexo tools improve the quality and productivity of work. For preparing images with spot color separations. See how spot colors and CMYK colors look in overprint, without having to make intermediate hardcopy proofs.
The Inkswitch filter can automatically calculate special ink separations to match the appearance of a CMYK target. The Newsletter keeps you updated on our products, applications and technologies. Language: English. Sign in My Account Forgot your password? Contact us Sales contacts Main offices. Try now for free. This inconsistency of X- and Y-dimensions typically indicates unexpected movement of the substrate as the barcode is applied by a printer or direct part marking device.
Contrast — The difference between the light and dark elements of a barcode, or between the code and its quiet zone and other perimeter elements. In this example, the dark elements etch marks and the light elements the substrate are too close in value due to low pressure in the marking process, undermining readability. Modulation — The uniformity of light and dark elements of a barcode.
In these examples, the dark elements of the symbol do not have a consistent value. This issue, like low contrast, is often due to inconsistent distribution of ink for printed codes or uneven abrasion for direct part marks. If there is not enough ink or pressure applied by printing or marking equipment, the result may be an underprint. Quiet Zone — The area surrounding a barcode that must be kept free of text, marks, or other obstacles.
In this example, a barcode has been printed outside of the designated quiet zone area and is overlapping with other elements on the substrate. This could be due to misalignment or movement of the substrate in relation to the printing equipment.
Low reflectance, as illustrated by this example, may increase the probability that a symbol element may be incorrectly identified as light or dark, causing a no-read result as the barcode reader attempts to interpret incorrect element patterns. Low reflectance may be caused by inconsistent print distribution or marking pressure by equipment. Possible Solutions It is important to inspect and maintain printing and marking equipment regularly to ensure that high-quality, consistent barcodes are produced and applied to parts to avoid no-reads.
If barcodes are produced by laser coding, correct focal distance and a continuous power supply to the equipment ensures high-contrast printing without losses in print distribution or speed. Thermal Transfer TTO and Direct Thermal DTO methods use wax or resin ribbon or other thermal media to apply barcodes to the substrate, so it is important to avoid ribbon wrinkles, to verify correct insertion of the ribbon into equipment, to use high-quality ribbon or other thermal material, and to use quality printheads and platen rollers for evenly-applied barcodes without missing elements.
Figure Ink-based case coding equipment prints linear barcodes directly onto cardboard packaging. Movement of products during printing and variations in product speed can greatly impact the quality of these barcodes at the time they are applied.
The key to producing high-quality marks by direct abrasion is consistent pressure of the abrading component against the substrate. It is important to verify the quality of the material used to create the abrasion laser, chemical, or metal stylus and the amount of power supplied to the marking equipment to ensure that barcodes are applied uniformly and with consistent pressure.
Figure A dot peen direct part marking system uses a metal stylus to pound elements into a metal surface. It is important to ensure mark pressure is consistent when marking to avoid uneven or low-contrast symbols. In addition to — and sometimes in lieu of — devoting excessive time and effort to maintaining perfectly-functioning printing and marking equipment, operators may choose to safeguard their operations against print or mark inconsistency by using more powerful barcode readers.
Of course, even with high-performance readers, regular maintenance of equipment should not be avoided. Damage or Distortion While printing and marking inconsistencies pose their own decoding challenges, the risk of no-reads can persist even with high-quality barcodes.
Barcode quality may degrade as parts move through operations and are exposed to various environmental factors. Harsh conditions may cause enough damage or distortion to the barcode or substrate to render even the best-quality barcodes unreadable. Damage can range from minor scratches, partial obstruction of the code by blotches, stains, or even debris causing torn or entirely missing barcodes. Distortion — Several environmental factors can contribute to barcode distortion in terms of shape, contrast, element uniformity, and substrate integrity.
Figure Environmental conditions have damaged this linear code to the point where significant portions of the bars have been blotched out, rendering it unreadable by standard equipment. Fixed Pattern Damage — Damage to patterns of barcode elements, which the reader interprets as data, can significantly undermine readability. These patterns allow the barcode reader to interpret the barcode orientation and number of rows and columns appropriately for decoding.
Obstruction of these symbol patterns by scratches, stains, debris, or other material can render the barcode unreadable. Figure The critical elements of a Data Matrix symbol, including the L-pattern, clock pattern, and data storage area.
Readability of the symbol is dependent capturing all critical elements clearly enough for the barcode reader to interpret data. Other Damage — The environmental conditions to which a barcode may be exposed are limitless, and so are the ways in which a barcode can incur damage. Any kind of damage that obstructs barcode elements from the view of the reader — unintended material abrasions, marks, surface stains, or excess material debris or even mounting fixtures — can cause no-read results.
The images below are just a few examples of barcode damage. Possible Solutions Once a barcode is released into a production environment, consistent barcode quality can be difficult to maintain.
In operations that use barcodes to track and identify items even after they have been transported between facilities or sold to customers to be read by new barcode reading equipment, the means for preventing or resolving barcode damage and distortion is very limited.
Some preparation can be done at the outset of code production to limit future damage — such as choosing a substrate resistant to harsh environmental conditions, printing or marking barcodes so they can withstand any anticipated environmental factors, and maintaining a production environment as free from potential sources of damage as possible. Figure Barcodes are read in a dusty food packaging facility, where extra care must be taken to ensure both barcodes and barcode readers withstand environmental conditions.
Certain code types provide the option of encoding special data to assist in the decode process even when the code is damaged. Error correction is encoded as elements in the data storage area of the code, increasing data recoverability by presenting symbol data to the reader in multiple ways. Almost all applications have accepted ECC Reed-Solomon error correction as the standard, as it is the best error correction methodology available for the Data Matrix code type.
Here, ECC symbol is reliably decoded despite partial obstruction. Although as much care as possible should be taken to prevent no-reads due to barcode damage, it is often preferable to focus on the capabilities of the barcode reader rather than on the barcode itself. For the most challenging applications, in which barcode damage or distortion is unpredictable, high-performance readers are usually installed from the outset.
Barcode readers engineered with the most powerful decoding algorithms feature advanced symbol location, gradient or reflectivity analysis, and the ability to grid-map the symbol image to produce an ideal, reliably-decodable symbol during processing. Barcode readers like these may also offer symbol reconstruction technology — a method by which the reader uses an algorithm to piece together discontinuous symbol data from multiple scan lines.
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