Patent ID: 8173038

Claim:
A method of forming microstructures on a glass substrate by laser ablation, the method comprising: directing a beam of a laser source onto a surface of the glass substrate and traversing the beam across the surface of the glass substrate such that a spot area of the beam forms a first pattern on the surface of the glass substrate as the beam is traversed across the glass substrate and glass is ablated from the glass substrate along the first pattern; and directing the beam of the laser source onto the surface of the glass substrate and traversing the beam across the surface of the glass substrate such that the spot area of the beam forms a second or subsequent pattern on the surface of the glass substrate as the beam traverses across the glass substrate wherein the second or subsequent pattern overlaps or intersects with the first pattern and glass is ablated from the glass substrate along the second or subsequent pattern thereby forming at least one microstructure on the glass substrate; and wherein the first pattern comprises a linear pattern of overlapping spot areas and the second or subsequent pattern comprises a linear pattern of overlapping spot areas substantially parallel with and overlapping the first pattern such that the at least one microstructure formed on the glass substrate is a plurality of tapered microstructure cavities wherein each tapered microstructure cavity in the plurality of tapered microstructure cavities has an opening having a diameter less than a diameter of a spot area of a laser pulse in the first pattern, a spot area of a laser pulse in a second pattern or both.