Abstract: A method for separating and releasing a closed-form piece from a workpiece made of a brittle material is disclosed. A first pulsed laser-beam creates defects along the outline of the closed-form piece. A second laser-beam selectively heats the closed-form piece for a first time that is sufficient to initiate cracking between the defects. The heating is stopped for a period sufficiently long for the cracks to propagate completely between the defects. The second laser-beam is applied for a second time that causes melting and deformation of the closed-form piece. The deformation opens a gap between the closed-form piece and the rest of the workpiece, thereby allowing release of the closed-form piece.

Abstract: Methods and apparatuses are disclosed for laser processing. A method includes providing a laser beam transparent to a workpiece. A cover, having a surface quality better than the workpiece's surface, is provided and spaced apart from the workpiece's surface. A fluid is provided between and in contact with the cover and the workpiece's surface. A laser beam is directed through the cover and fluid to the workpiece. An apparatus includes a cover spaced apart from a workpiece's surface and including a surface quality better than the workpiece's surface, a fluid dispenser for introducing fluid between and in contact with the cover and the workpiece's surface, and a laser system that directs a laser beam through the cover and fluid to the workpiece.

Abstract: A method for separating and releasing a closed-form piece from a workpiece made of a brittle material is disclosed. A first pulsed laser-beam creates defects along the outline of the closed-form piece. A second laser-beam selectively heats the closed-form piece for a first time that is sufficient to initiate cracking between the defects. The heating is stopped for a period sufficiently long for the cracks to propagate completely between the defects. The second laser-beam is applied for a second time that causes melting and deformation of the closed-form piece. The deformation opens a gap between the closed-form piece and the rest of the workpiece, thereby allowing release of the closed-form piece.