Code 49

Code 49 is a stacked, variable-length symbology developed by Intermec to pack a large amount of alphanumeric data into a very small label area.

Introduction

Code 49 was developed by David Allais in 1987 at the Intermec Corporation to fill a need to pack a lot of information into a very small symbol. Code 49 accomplishes this by using a series of bar code symbols stacked one on top of another. Each symbol can have between two and eight rows. Each row consists of a leading quiet zone; a starting pattern; four data words encoding eight characters, with the last character a row check character; a stop pattern; and a trailing quiet zone. Every row encodes the data in exactly 18 bars and 17 spaces, and each row is separated by a one-module high separator bar.

The code is a continuous, variable-length symbology that can encode the complete ASCII 128-character set. Its structure is actually a cross between UPC and Code 39. Intermec has put the code in the public domain.

Density and Applications

The minimum value of the x-dimension is 7.5 mils for a symbol to be read by an unknown reader. Assuming an x-dimension of 7.5 mils, and a minimum 8-row symbol height of .5475 inches, the maximum theoretical density is 170 alphanumeric characters per square inch. For a health industry symbol with a flag character, a 10-digit NDC number, a 5-digit expiration date, and a 10-character alphanumeric lot code, the symbol would be .3 inches by .53 inches. A 15-digit printed circuit board serial number Code 49 symbol would be only .1 inches by .3 inches.

Scanning and Printing

Code 49 can be scanned with modified moving-beam laser scanners or a CCD scanner. Intermec makes a CCD scanner that decodes Code 49 symbols along with standard bar code symbologies. Labels can be printed using standard printing technologies.

For more information visit Intermec's website.