Conformance Calibration Standard Test Cards for Barcode Verifiers

INTRODUCTION:

Barcode symbols have become ubiquitous machine-readable data carriers throughout the world.  In order to ensure they can be reliably produced and then decoded at their point of use, barcode verifiers have become the standard method of measuring and assessing the quality of the symbol, both during production and afterwards.  Early on in the development of barcode technologies, it became apparent that a consistent method for ensuring the accuracy and consistency of barcode verifiers from all manufactures was required.

The family of APPLIED IMAGE Conformance Calibration Standard Test Cards have become the industry gold standard by which barcode symbol verifiers can be calibrated, and operators trained, to ensure they are providing accurate and repeatable results in accordance with ISO/IEC 15426-1 for 1D symbols and ISO/IEC 15426-2 for 2D symbols.

The primary reference test symbols contained on the test card, are symbols intended for testing the accuracy of the barcode verifier being used.  They are barcode symbols with known defects engineered in to them, manufactured to very precise tolerances, and then measured so that the measured parameter values of the test card can be compared to the verifier being calibrated.

The symbols have each been measured in an ISO/IEC 17025:2017 accredited calibration laboratory on a device nicknamed “THE JUDGE.”  This calibration instrument has been specifically designed, built, and calibrated to provide ten times the precision of the verifier to be tested with performance traceable to national standards for reflectance and linear distance.  THE JUDGE uses ISO/IEC 15416 grading methodology for Linear Symbols (1D) and ISO/IEC 15415 grading methodology for Two Dimensional Symbols (2D).

PROCEDURE FOR TESTING A BARCODE VERIFIER:

A barcode verifier becomes a measurement device within your quality system and should be monitored on some regular frequency to be sure it is operating within the manufacturer’s operating window.  The following validation procedure should be used based on the frequency determined by your own quality system and/or the manufacturer’s recommendations.

  1. Follow the manufacturer’s recommended procedure for set up of the equipment to obtain a proper functioning verifier.
  2. Practice using the manufacturer’s procedure to obtain just the right touch of verifier/operator technique. The idea is to obtain a certain sense of uniform consistency when verifying a symbol.
  3. ISO/IEC standards state that the number of scans should normally be 10, which are taken across the symbol to obtain an average value. The average reading should match the published value on the test card to within the verifier manufacturer’s specifications.
  4. If the verifier agrees with the value on the card, within the tolerance range of the manufacturer, then the verifier/user combination is considered to be acceptable and operating properly. If, after repeated attempts, the verifier does not provide the correct value within the manufacturer’s published range, then the verifier or operator must be suspect. Please note that verification procedures can be quite sensitive to operational technique. Therefore, the operator should practice sufficiently to develop the proper technique with guidance provided by the manufacturer of the equipment. If the operational technique is in control and the calibration procedure is still not providing accurate or consistent results, then the operator manual should be consulted to find a proper resolution for this issue, or contact the manufacturer of the equipment.

TEST CARD CALIBRATION STATUS:

The APPLIED IMAGE Conformance Calibration Standard Test Card serves as a primary reference standard, with a traceability chain to national standards, for all barcode verifiers calibrated using it and is sold with supporting calibration data and certificate.

  1. The Conformance Calibration Standard Test Card is certified to be in conformance with applicable standards (ISO/IEC 15416 and ISO/IEC 15426-1 or ISO/IEC 15415 and ISO/IEC 15426-2), and traceable to NIST (National Institute of Standards and Technology) or another NMI (National Metrology Institute).
  2. This Conformance Calibration Standard Test Card is certified for a period of 24 months from first use (in-service date) but no more than 48 months from the calibration date. Replacement or recalibration is recommended after 24 months of use.
  3. When not in use, store the test card in a clean, dry environment protected from UV light. Care should be taken not to touch the barcodes on the test card.  Any visual scratches, smudges, fingerprints or other marks may compromise the integrity of the test symbol.  A clean, defect free scan path or image area MUST be available in order to obtain a proper measurement. If sufficient defects develop affecting the measured parameter values from the test card, the Calibrated Conformance Standard is NO LONGER VALID and SHOULD BE REPLACED.

It is recommended that the test card be handled only with clean, lint-free gloves. Any attempt to clean the test card (other than with a soft, clean optics brush) may change the calibrated value and should not be used.