METHOD AND APPARATUS FOR PERFORMING LASER FILAMENTATION WITHIN TRANSPARENT MATERIALS

摘要

Systems and methods are described for forming continuous laser filaments in transparent materials. A burst of ultrafast laser pulses is focused such that a beam waist is formed external to the material being processed without forming an external plasma channel, while a sufficient energy density is formed within an extended region within the material to support the formation of a continuous filament, without causing optical breakdown within the material. Filaments formed according to this method may exhibit lengths exceeding 10 mm. In some embodiments, an aberrated optical focusing element is employed to produce an external beam waist while producing distributed focusing of the incident beam within the material. Various systems are described that facilitate the formation of filament arrays within transparent substrates for cleaving/singulation and/or marking. Optical monitoring of the filaments may be employed to provide feedback to facilitate active control of the process.

主权项

1. A method of laser processing a transparent material, said transparent material being transparent to the wavelength of said laser, comprising the steps of:
providing a laser beam, said laser beam includes a burst of laser pulses, said burst is defined as a single laser pulse or multiple laser pulses; externally focusing said laser beam relative to said transparent material to form a beam waist at a location that is external to said transparent material while avoiding the formation of an external plasma channel; and, said laser pulses are focused such that a sufficient energy density is maintained within said transparent material to form a continuous laser filament therein without causing optical breakdown of said transparent material.