100% traceability in production is a requirement, together with quality assurance conforming to ISO 9000. The requisite identification number has to be machine-readable to enable detection in all phases of production and also in the case of returns.
On small products there may be a problem due to lack of space. As a rule this can be solved by using the Data Matrix ECC 200. This 2D-code is used to encode characters in a very small space. The limits are only set by the respective printing technology employed. The label is a tried and trusted means of identification. Modern methods facilitate the manufacture and automatic application of labels in the 5mm x 5mm format. These enable a data matrix code with a module size of 12 x 12 to be positioned in the thermal-transfer printing process. This permits, for example, the representation of a 10-digit number.
In the practical example a printer with 300 dpi has been used. At 4 dots per module this provides a code size of 4mm x 4mm. This also ensures the maintenance of the requisite code rest zone. Such codings can be read with the ODT-MAC310 Data Matrix Reader during motion. Hand-held devices from various manufacturers are available for manual detection.
Alternatively, direct marking methods can be used, such as laser and inkjet lettering. However, in these cases the feasibility must be ascertained in each individual application. In particular, the readability with standard reading devices is not always guaranteed, since generated codes of this type do not satisfy the quality levels of the standard.