Marking Tabs With A Two Dimensional Code

摘要

A method for forming a Data Matrix Code or like two dimensional code on a beverage can tab uses a laser having a focal ratio of between 40 and 70 to produce spots having an average diameter of between 200 and 400 microns. The code is smaller than 6 mm by 6 mm, at least 12 modules by 12 modules, and smaller than 21 modules by 21 modules, thereby providing sufficient quantity of unique codes for use with commercial beverage can quantities. Preferably each module is formed by one laser spot. Alternatively, nine spots may be used to form a module.

主权项

1. A method for marking a code on a beverage can tab structure, comprising the steps of:
on a surface on a body portion of the beverage can tab structure having a coating that is dark, (i) applying an approximately round laser light onto a first location on the surface at tab making production speed to achieve a light spot; and after the applying step (i), (ii) repeatedly applying the approximately round laser light onto other locations on the surface on the body portion of the beverage can tab structure to achieve other light spots, wherein the laser light in the applying steps (i) and (ii) disturbs the coating, thereby forming light-colored elements having a minimum dimension of at least 200 microns, the elements forming a two dimensional code that is readable by a wireless communication device.