52 results about "Laser pulse duration" patented technology

In one aspect the invention provides a method for laser induced breakdown of a material with a pulsed laser beam where the material is characterized by a relationship of fluence breakdown threshold (Fth) versus laser beam pulse width (T) that exhibits an abrupt, rapid, and distinct change or at least a clearly detectable and distinct change in slope at a predetermined laser pulse width value. The method comprises generating a beam of laser pulses in which each pulse has a pulse width equal to or less than the predetermined laser pulse width value. The beam is focused above the surface of a material where laser induced breakdown is desired. The region of least confusion (minimum beam waist or average spot size) is above the surface of the material in which laser induced breakdown is desired since the intensity of the beam falls off in the forward direction, preferably the region of the beam at or within the surface is between the region of least confusion and sufficient to remove material and the minimum intensity necessary for laser induced breakdown of the material to be removed, most preferably the region of minimum intensity is disposed at the surface of the material to be removed. The beam may be used in combination with a mask in the beam path. The beam or mask may be moved in the x, y, and Z directions to produce desired features. The technique can produce features smaller than the spot size and Rayleigh range due to enhanced damage threshold accuracy in the short pulse regime.

A method of making an at least one hole in an optically transparent body comprises the following steps: (i) providing an ultrashort pulse laser for producing a laser output with a wavelength λ, the laser output having a subpicosecond laser pulse duration; (ii) providing a laser output focusing lens for focusing the laser output, the focusing lens having a numerical aperture NA; (iii) providing an optically transparent body, the optically transparent body having a transparency at λ of at least 90% / cm; (iv) providing a liquid filled container situated proximate to the optically transparent body, such that the optically transparent body is in direct contact with the liquid; and (v) directing the laser output through the focusing lens to produce a focused laser output with a subpicosecond laser pulse duration proximate the optically transparent body, wherein the focused laser output traces at least one hole track pattern through the transparent glass body while the optically transparent body and said focused laser output move relative to one another in X-Y-Z directions. The at least one hole track pattern is in contact with the liquid and the focused laser output, in conjunction with the liquid, creates at least one hole in the optically transparent body.

There is described a method for producing a hole using e.g. a lasers, wherein short laser pulse durations are used. The laser pulse durations are varied, short laser pulse durations being utilized only in the area to be removed in which an influence on the penetration behavior and discharge behavior is noticeable while longer pulse durations of >0.4 ms are used. This is the case for the inner surface of a diffuser of a hole, for example, which can be produced very accurately by means of short laser pulse durations.