Optical Character Recognition (Unicode block)

Optical Character Recognition is a Unicode block containing signal characters for OCR and MICR standards.

Block

Subheadings

The Optical Character Recognition block has three informal subheadings (groupings) within its character collection: OCR-A, MICR, and OCR.

OCR-A

The OCR-A subheading contains six characters taken from the OCR-A font described in the ISO 1073-1:1976 standard: U+2440⑀ OCR HOOK, U+2441⑁ OCR CHAIR, U+2442⑂ OCR FORK, U+2443⑃ OCR INVERTED FORK, U+2444⑄ OCR BELT BUCKLE, and U+2445⑅ OCR BOW TIE. The OCR bow tie is given the informative alias "unique asterisk".

The hook, chair and fork, in addition to a long vertical bar, are included in the most basic "numeric" implementation level of OCR-A, which includes digits but excludes letters and conventional punctuation. By contrast, the most basic implementation level of OCR-B instead includes the digits, plus sign, less-than sign, greater-than sign, long vertical bar and seven of the capital letters; as such, there are no characters specific to OCR-B in the Optical Character Recognition block.

MICR

The MICR subheading contains four punctuation characters for bank cheque identifiers, taken from the magnetic ink character recognition E-13B font (codified in the ISO 1004:1995 standard): U+2446⑆ OCR BRANCH BANK IDENTIFICATION, U+2447⑇ OCR AMOUNT OF CHECK, U+2448⑈ OCR DASH, and U+2449⑉ OCR CUSTOMER ACCOUNT NUMBER.

The latter two characters are misnamed: their names were inadvertently switched when they were named in the 1993 (first) edition of ISO/IEC 10646, a mistake which had been present since Unicode 1.0.0. Although their formal names remain unchanged due to the Unicode stability policy, they both have corrected normative aliases: U+2448 ⑈ is MICR ON US SYMBOL, and U+2449 ⑉ is MICR DASH SYMBOL (the standard notes that "the Unicode character names include several misnomers").

These symbols had previously been encoded by the ISO-IR-98 encoding defined by ISO 2033:1983, in which they were simply named SYMBOL ONE through SYMBOL FOUR. All four characters have informative aliases in the Unicode charts: "transit", "amount", "on us", and "dash" respectively.

OCR

The OCR subheading consists of a single character: U+244A⑊ OCR DOUBLE BACKSLASH.

History

The following Unicode-related documents record the purpose and process of defining specific characters in the Optical Character Recognition block: