A Rofin solid state laser has been used to mark an ID matrix code on a steel fixing pin head. The 16x16 element code can encrypt up to 24 numeric characters, or 16 alphanumeric.
Black laser marks are created on carbon steels by oxidisation of components in the alloy and by bringing carbon to the surface. The mark is permanent and the contrast provides a good degree of readability for automated identification. ID matrix codes are routinely laser marked onto parts in automotive, aerospace, electronics and medical device industries.