Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for identifying, by a computer system, at least one line of a plurality of lines that are disposed at a first layer of a card; providing, by the computer system and based on the identified at least one line, control signals to a laser device of the computer system, the control signals indicating coordinates for the identified at least one line; generating, by the laser device and based on the control signals, one or more line patterns that are embedded at a particular layer of the card.