Double far-side laser ablation

The present application describes a method for laser scribing first and second transparent electrically conductive layers (14, 14′) deposited on respective opposing first and second surfaces (12, 13) of a transparent substrate (11), the method comprising: directing a first laser beam (21) through one or more lenses (22) to a focal spot on or closely adjacent to the first surface (12) of the substrate (11), such that the focusing laser beam (21) passes through the second electrically conductive layer (14′) and the second surface (13) of the substrate (11); initiating relative movement between the first laser beam (21) and the substrate (11) in two axes in a plane orthogonal to the axis of the first laser beam (21) to scribe a first pattern in the first electrically conductive layer (14); directing a second laser beam (21′) through one or more lenses (22′) to a focal spot on or closely adjacent to the second surface (13) of the substrate (11), such that the focusing laser beam (21′) passes through the first electrically conductive layer (14) and the first surface (12) of the substrate (11), initiating relative movement between the second laser beam (21′) and the substrate (11) in two axes in a plane orthogonal to the axis of the second laser beam (21′) to scribe a second pattern in the second electrically conductive layer (14′).