Implementations
In 1968, American Type Founders produced OCR-A, one of the first optical character recognition typefaces to meet the criteria set by the U.S. Bureau of Standards. The design is simple so that it can be easily read by a machine, but it is more difficult for the human eye to read.
As metal type gave way to computer-based typesetting, Tor Lillqvist used MetaFont to describe the OCR-A font. That definition was subsequently improved by Richard B. Wales. Their work is available from CTAN.
To make the free version of the font more accessible to users of Microsoft Windows, John Sauter converted the MetaFont definitions to TrueType using potrace and FontForge in 2004. In 2007, Gürkan Sengün created a Debian package from this implementation.
In 2008. Luc Devroye corrected the vertical positioning in John Sauter's implementation, and fixed the name of lower case z.
Independently, Matthew Skala used mftrace to convert the Metafont definitions to TrueType format in 2006. In 2011 he released a new version created by rewriting the Metafont definitions to work with METATYPE1, generating outlines directly without an intermediate tracing step.
In addition to these free implementations of OCR-A, there are also implementations sold by several vendors.
Read more about this topic: OCR-A Font