Optimizing Processes with RFID and Auto ID, 2009

3 Optical codes
Kirsten Drews
For some 40 years, there has been a constantly increasing requirement
to label items in industry and trade with automatically readable
markings and, therefore, to enable identification during the course of
the entire production process and the supply chain up to the end customer.
3.1 Success and limits of barcodes
The greatest success so far was the linear codes (also: 1D codes, Barcodes),
for example, the EAN codes on sales packaging. However, barcodes
display some very distinct restrictions, maintaining the need
for further developed technology:
• Analog data encoding (measurement of the bar widths and
spacing)
• High space requirements, above all for the width for larger data
quantities
• Use of labels that are necessary or a restriction on printing on
paper or plastic
• Poor data security
• Reading that is only possible from one direction or omni-directional
scanning that is only possible with expensive additional
measures.
In addition to the developments in the field of radio technology
(RFID), optical encoding technologies were also researched further.
Piled linear codes, such as PDF417 or Codablock, or the even more
effective two-dimensional digital codes (also the so-called Matrix
codes, 2D codes), can achieve the following objectives:
• Reduction of required space
• Simplification of omni-directional reading
38