초록 ▼

A nonvolatile electro-optical read-only memory includes a substrate on which is printed (or otherwise inscribed) a complex symbol or “label”with a high density two-dimensional symbology, a variable number of component symbols or “codewords”per row, and a variable number of rows. Codewords in alterna

A nonvolatile electro-optical read-only memory includes a substrate on which is printed (or otherwise inscribed) a complex symbol or “label”with a high density two-dimensional symbology, a variable number of component symbols or “codewords”per row, and a variable number of rows. Codewords in alternating rows are selected from mutually exclusive subsets of a mark pattern such as a (17,4) mark pattern. The subsets are defined in terms of particular values or a discriminator function, which is illustrated as being a function of the widths of bars and spaces in a given codeword. In the illustrated embodiment, each subset includes 929 available codewords; that, plus a two-step method of decoding scanned data, permitting significant flexibility in defining mappings of human-readable symbol sets into codewords. The memory may be used in conjunction with a scanner and a suitable control system in a number of applications, e.g., robotic operations or automated microfilm searching.

대표청구항 ▼

A machine readable data file structure comprising: (a) at least two rows of codewords, one row being adjacent to and beneath another row; (b) each said codeword representing at least one information-bearing character and being selected from among a set of detectable mark patterns; (c) each of said m

A machine readable data file structure comprising: (a) at least two rows of codewords, one row being adjacent to and beneath another row; (b) each said codeword representing at least one information-bearing character and being selected from among a set of detectable mark patterns; (c) each of said mark patterns comprising a pattern of marks, each of said marks being representative of one of a plurality of different states; (d) the codewords in each said row being selected from a subset of said mark patterns, the subset for said row being defined by a specified rule for each of said rows that differs from the rule specified for said adjacent row; and (e) each said rule being a function of respective widths of said marks.