NCR 7870 manual Bar Code Quality

6-6 Chapter 6: Operation

Bar Code Quality

Many labels in a typical retail environment are unreadable. The illustration shows some of the common problems. Vendors and printers regularly supply products to the market with bar codes that are overprinted, underprinted, or truncated. Some labels have missing margins. Others may be printed around the corners of packages, or on media not likely to remain flat when picked up.

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R0026

The readability of a label depends on variables such as size, placement, color, paper type, ink viscosity, and package coatings. The middle of a printing run can yield erroneous labels due to the many variants involved. In particular, poor color contrast and marginal print quality can make a label hard to read.

A label should be considered readable if it meets or exceeds the requirements set forth in the UPC Symbol Specification published by the UPC Council, Inc. (March 1982), and the General Specification for Article Symbol Marking, Copyright EAN-1977.