Magnetic Ink Character Recognition (MICR) was developed to take advantage of computer technology in the banking industry. Prior to using the MICR line, sorting checks by account number was a manual process. Two systems have historically been used to process the large number of checks processed in the banking industry:
Sort-A-Matic and the Top Tab Key Sort. It contained 100 metal or leather dividers numbered from 00. up to 99. Each check was placed in the appropriate compartment by the first two digits of the account. The sorting process was then repeated for the next two digits of the account number. After the process was complete, the checks were grouped by account number. In the
top tab key sorting system, a small hole punched above the check indicated the number. For example, the first hole showed the value of the first digit (0, 1, 2, 3...). A metal "key" was inserted into the hole to separate all checks with the same first digit value, and this procedure was repeated for each digit until all checks were classified.
Both systems worked, but took a long time. With the advent of computers and the shift from the laboratory to the world of business, the task of sorting and matching seemed ideal. Stanford University and Bank of America have successfully used computers to sort and reconcile checks for the first time. They developed what is now known as MICR. Evolution of the
MICR Font The
MICR font was developed by Stanford University in collaboration with the Bank of America and is endorsed by the American Banking Association. This font is known as his E-13B font. The E-13B has a total of 14 characters:
specially designed 10 numbers (0 to 9) and 4 special symbols (Transit, Amount, On-Us, Dash).
The letter E indicates the fifth version considered. The letter B marks his second revision of this version. The number 13 comes from the 0.013 inch modular construction used for the width of the bars and letters. This means that all character widths, both horizontal and vertical, are multiples of 0.013 inches in the range 0.052 to 0.091. I'll explain more about what this means later in this article.
MICR Readers Three different machines are used to read
MICR characters. Two that read characters magnetically are called MICR readers. The third machine is an OCR (optical character recognition) reader. The
E-13B characters are printed with a magnetizable iron oxide toner. The MICR reader passes a check containing the E-13B magnetic letter through a magnet, thereby magnetizing the iron oxide particles. Magnetized characters pass through a magnetic read head. The magnetic field (flux pattern) produced by the magnetized characters induces a current in the read head. The strength and timing of this stream allows the reader to decipher the characters. The
magnetic reader comes in two varieties: the
single-track (single-slit or split scan) reader and he multi-track (matrix or pattern) reader. How the
Single Track Reader Works The
single track reader uses a gapped read head to detect the magnetic flux patterns created by the MICR characters. As the magnetized E-13B printed character moves across the narrow gap of the read head, the voltage generated by the character's magnetic flux creates a unique waveform for each character. How the
Multitrack Reader Works The
multitrack reader uses an array of small vertically aligned read heads to detect the presence of magnetic flux patterns. Small individual read heads slice across the characters and detect the presence of magnetic flux. By sensing the magnetic flux over time, the unique.
