초록 ▼

A method and apparatus for reading optical symbols is disclosed, which employs defined erasure zones for grading symbols, and for permitting soft decisions to be made with respect to further processing of the symbols. The erasure zones are defined between nominal values within the range of nominal v

A method and apparatus for reading optical symbols is disclosed, which employs defined erasure zones for grading symbols, and for permitting soft decisions to be made with respect to further processing of the symbols. The erasure zones are defined between nominal values within the range of nominal values for the measurable characteristics of the symbol elements which comprise the symbol. The measured actual values of the measurable characteristic are compared to the erasure zones. The number of symbol elements having measured actual values within any one of the erasure zones is used to determine the appropriate steps for further processing of the optical symbol. Measurable characteristics can include dimensions such as width, length, area, volume, as well as other optical characteristics such as color or hue, and shade or depth.

대표청구항 ▼

[ What is claimed is:] [1.] A method of operating a bar code reader to decode a bar code symbol, the bar code symbol composed of a plurality of bar and space elements, each of the bar elements associated with a nominal value selected from a range of nominal values including narrow and wide, the meth

[ What is claimed is:] [1.] A method of operating a bar code reader to decode a bar code symbol, the bar code symbol composed of a plurality of bar and space elements, each of the bar elements associated with a nominal value selected from a range of nominal values including narrow and wide, the method comprising the steps of:scanning the bar code symbol to produce a set of dimensional data points corresponding to a measured actual dimension of each of the bar elements;defining at least one erasure zone between a pair of nominal values in the range of nominal values such that a lower threshold of the erasure zone is greater than a first one of the pair of nominal values and an upper threshold of the erasure zone is less than a second one of the pair of nominal values;comparing each of the dimensional data points in the set of dimensional data points with the erasure zone.