Laser processing a multi-device panel

A system for processing a multi-device panel, comprising a substrate having a front surface and a rear surface, a first array of device regions on the front surface and a second array of device regions on the rear surface, by vector direct-write laser ablation, the system comprising:

• a first processing station that includes a pair of opposedly-mounted processing heads, each processing head including a laser beam delivery apparatus having a laser beam scanner and a lens unit, and a distance measurement means;
• mounting means for mounting the panel between the processing heads of the first processing station such that a relative position of the panel and the first processing station can be adjusted so that the processing heads are brought into alignment with selected front-surface and rear-surface device regions to be processed;
• wherein each processing head is operable to make an estimate of a distance between the lens unit and the surface of the device region to be processed using the distance measurement means,
• wherein each processing head is operable to control a focus by moving the lens unit dependent on said estimate of the distance;
• and
• wherein each processing head is operable to vector direct-write the device region.