Introduction
Code
1 was invented by Ted Williams in 1992 and is the earliest
public domain matrix symbology. It uses a finder pattern of
horizontal and vertical bars crossing the middle of the symbol.
Code 1 is the code announced in 1991 by Laser Light Systems.
Code 1 is a two-dimensional matrix symbology containing dark and light square data modules and a finder pattern of parallel lines in the symbol's interior. A two-dimensional imaging device such as a CCD camera is necessary to scan the symbology.
Code 1 is designed with a fixed level of error correction capability. It supports industry standard escape sequences to define international code pages and special encodation schemes. Code 1 is used both for large data file encoding and small item marking applications. This document includes descriptions of the character encodation, symbol structure, reference decode algorithm, and symbol quality measurements for Code 1.
The symbol can encode ASCII data, error correction data, function characters, and binary encoded data. There are 8 sizes ranging from code 1A to code 1H. Code 1A can hold 13 alphanumeric characters or 22 digits while code 1H can hold 2218 alphanumeric characters or 3550 digits. The largest symbol version measures 134x wide by 148x high. The code itself can be made into many shapes such as an L, U, or T form.
Code 1 is currently used in the health care industry for medicine labels and the recycling industry to encode container content for sorting.