Key Takeaways
Here’s what you’ll uncover about speckle-free lasers:
- Speckle-free lasers reduce random height errors for precise 3D measurements
- The In-Sight L38 delivers crisp, high-resolution 3D and 2D imaging
- Faster inspections cut costs and boost production
The International Organization for Standardization (ISO) is an independent, non-governmental global organization that develops and publishes international standards across various industries. ISO standards for manufacturing set clear, recognized guidelines that help ensure products are safe, high-quality, and made efficiently. By adhering to these standards, manufacturers can reduce errors, ensure regulatory compliance, and drive continuous improvement. This not only boosts customer satisfaction and trust but also helps manufacturers stay competitive, demonstrate reliability, and achieve long-term success.
The impact of barcode standards
Following barcode quality standards improves accuracy and enhances overall operations. Here’s why they make a difference:
- Consistent quality reduces scanning errors and enhances data reliability.
- Clear standards streamline barcode scanning, speeding up processes.
- Uniformity ensures barcodes are easily read across different systems.
- Meeting standards helps businesses stay compliant with regulations.
There are hundreds of ISO standards, many of which relate to barcodes, covering aspects like data encoding, decoding, sizing, and more. Only three ISO standards pertain to barcode quality:
- ISO 15416 for 1D barcodes
- ISO 15415 for 2D label-based barcodes
- ISO/IEC TR 29158 for 2D DPM Direct Part Marking (DPM) codes (or AIM DPM)
Understanding ISO verification standards
ISO 15416: This 1D barcode ISO standard requires scanning across 10 individual lines throughout the height of the code, with each scan line receiving a grade determined by many different parameters. If a scan line fails to meet minimum reflectance, decode, or edge contrast, it automatically gets an “F” grade. If all three conditions are met, the software grades symbol contrast, modulation, defects, and decodability parameters on a scale of A to F. Once all 10 scan lines are graded, the average score is calculated to determine the barcode’s overall grade.
Minimum Reflectance checks whether the bars are dark enough to meet the required ratio of light that is reflected off of the spaces.
Edge Contrast measures the difference between adjacent bars and spaces.
Modulation refers to local variations in contrast.
Decode checks to see whether the code can be read using the standard reference decode algorithm.
Defects include printing errors, dirt, or markings that affect one single bar or space.
Decodability grades the accuracy of bar and space widths compared to their ideal size. A barcode with bar width growth or distortion will score a low decodability grade.
ISO 15415: This standard evaluates 2D barcodes against eight different parameters, with the lowest individual grade determining the overall grade. The grading process starts with a pass/fail test – if the barcode can be decoded, it passes; if not, it automatically receives an “F” grade. To identify reasons for a failed decode, consider the following questions:
- Are you using the right aperture, ISO standard, and lighting angle?
- Is the symbology enabled? Is the camera in focus?
- Is the code in the center of the field of view?
- Do the cell sizes look proportionate to one another?
- Are all the components of the finder pattern present?
After a code is decoded, the following parameters are then graded.
Symbol Contrast refers to the difference between the darkest and the lightest modules.
Modulation measures local variations in contrast.
Fixed Pattern Damage includes errors with the L sides or clock pattern or quiet zone.
Axial Non-uniformity refers to the uneven scaling of the code.
Grid Non-uniformity measures the biggest deviation from the grid.
ISO/IEC TR 29158 (AIM DPM)
The quality parameters and grading process for DPM codes are similar to ISO 15415, with a few key differences. One major difference is how the global threshold is determined. The global threshold, which separates light and dark cells, defines the color of a cell. To accommodate various background surfaces, AIM DPM uses a more advanced algorithm than ISO 15415 to calculate this threshold, often resulting in improved modulation. AIM DPM also allows the use of 30-, 45-, 90-degree, and dome lighting. This makes verification on parts that are curved, reflective, or marked using dot peen possible.
Some industry committees have developed application standards that specify which ISO standards should be used for grading, covering sectors such as medical devices, retail, transportation, food service, and the U.S. Department of Defense.
Ensuring barcode quality, every time
Cognex is a leading provider of advanced solutions that enhance industrial connectivity, helping businesses achieve greater efficiency, accuracy, and performance. Our durable and reliable DataMan barcode readers deliver industry-leading read rates, decoding all types of 1D and 2D codes, including printed labels and the hardest to read DPM codes. The DataMan series offers both handheld and fixed-mount options, providing high-performance scanning and no moving parts that can wear out or fail, making them ideal for industrial settings.