What is Barcode Verification?
Barcode Verification measures the printed quality of the bar code to international (ISO) standards. This is the GS1 standard used by retailers worldwide. All barcodes printed should be verified using an ISO approved verifier to prevent costly rejects, product recalls, and scanning failures. Verification also ensures compliance with industry standards for proper data encoding to maintain supply chain efficiency.
Barcode inspection evaluates and measures the ISO defined quality parameters for linear (UPC) and 2D (QR code, Datamatrix) barcode Symbology’s. The verifier analyzes the barcode and assigns a grade (A-F) based on the elements of a barcode that affect successful scanning.
A linear barcode verifier (ISO 15416) measures several different parameters of a barcode:
- How black and white it appears to a scanner (Symbol contrast)
- Whether the dark bars have enough difference from the white spaces (Minimum reflectance)
- The least distinct difference between a bar and a space (Edge contrast minimum)
- How much the contrast between black and white varies across the barcode (Modulation)
- The presence of white marks in the bars or dark marks in the spaces (Defects)
- How accurate the different widths of the bars and spaces of the barcode are (Decodability)
- Determines whether a reference decode algorithm is detected for a specific data structure (Ex. UPC) or Symbology (Ex. Code 128) (Decode)
A 2D barcode verifier (ISO 15415) measures these same parameters AND additional ones correlating to 2D barcodes:
- Unused Error Correction (UEC). Determines how much margin exists before the code becomes unreadable.
- Axial and Grid Nonuniformity Fixed pattern damage – evaluates the quality and integrity of the fixed elements.
- Quiet zones – Detects Damage in quiet zones of symbol
- Print Growth – module increases due to ink gain or spread
A linear barcode verifier will measure seven different parameters of the barcode:
- How black and white it appears to a scanner (Symbol contrast)
- Whether the dark bars have enough difference from the white spaces (Minimum reflectance)
- The least distinct difference between a bar and a space (Edge contrast minimum)
- How much the contrast between black and white varies across the barcode (Modulation)
- The presence of white marks in the bars or dark marks in the spaces (Defects)
- How accurate the different widths of the bars and spaces of the barcode are (Decodability)
- Whether the light margins on each side, the encodation of data, and the check digit are all correct (Decode)
