초록 ▼

Systems (apparatus and methods) for reading bar code data detect light reflected and/or refracted from a target. The detected light is converted into an electrical signal containing width values that are indicative of widths of light areas and dark areas of the target. Systems for pre-screening data

Systems (apparatus and methods) for reading bar code data detect light reflected and/or refracted from a target. The detected light is converted into an electrical signal containing width values that are indicative of widths of light areas and dark areas of the target. Systems for pre-screening data read by a bar code reader determine whether sequences of width values are consistent with potential bar code data by comparing the relative widths of subsequences of light areas and dark areas. If the relative widths are consistent with bar code data, the width values of the sequence being pre-screened are output to a decoder, which attempts to read the sequence of width values. If the relative width values are inconsistent with bar code data, the sequence of width values is not output to the decoder, thereby decreasing the amount of processing the decoder would otherwise be required to perform.

대표청구항 ▼

1. A method for pre-screening data read by a bar code reader, comprising the steps of:receiving a width signal comprised of width values that are indicative of widths of light areas and dark areas read from a target; selecting a sequence of width values from the width signal, wherein the sequence co

1. A method for pre-screening data read by a bar code reader, comprising the steps of:receiving a width signal comprised of width values that are indicative of widths of light areas and dark areas read from a target; selecting a sequence of width values from the width signal, wherein the sequence contains at least three width values occurring consecutively in the width signal, and wherein the sequence comprises a number of subsequences of width values, each subsequence containing a number of consecutive width values; and determining whether all subsequence ratios contained in said sequence are within a range of acceptable sum ratios, each subsequence ratio being a ratio of a width of a subsequence to a width of another subsequence, and wherein said range is bounded by a maximum sum ratio and a minimum sum ratio.