Process Date: February 1999

This 2-D bar code reads "Synrad CO₂ Laser marking!"
Information-dense 2D codes can be quickly and easily marked directly onto the base material of PCBs using a low power sealed CO₂ laser and galvo’ based marking head – an excellent application for the Fenix laser marker or Digital Marking Head. The mark in the photograph was created with a 69mm lens, using only 1 watt of laser power, at a speed of 10"/s (the cycle time was 2.21 seconds). The exact dimensions of this Datamatrix 22-cell bar code are 0.115 x 0.115", with each cell only 0.00522" square.

2-D bar codes need only a 20% contrast to be readable, and so are much easier to mark and read than 1-D codes, which require up to 80% contrast. In addition, the 2-D code area is significantly smaller than equivalent single bar codes.

Other great materials for 2-D bar coding are FR4, Bakelite (inverted barcode), and selected metals.