Material processing by turbo burst ultrafast laser pulse
A method for scribing transparent material with a laser is provided. The method includes providing relative movement between the laser and the transparent material, pulsing the laser at a first pulse repetition rate in a kHz range to establish a speed of scribing of the transparent material, and forming each of said first laser pulses with a series of second laser pulses having a second pulse repetition rate in a MHz range, wherein each of said second lasers pulses is formed from a series of third laser pulses having a third pulse repetition rate in a GHz range.
1 . A method for scribing transparent material with a laser, comprising:
providing relative movement between the laser and the transparent material, the transparent material having a top surface and a bottom surface;
pulsing the laser at a first pulse repetition rate in a kHz range from 1 KHz to less than 1000 kHz to form a plurality of first laser pulses and to establish a speed of scribing of the transparent material, wherein each of the first laser pulses is comprised of a series of second laser pulses having a second pulse repetition rate in a MHz range from 1 MHz to less than 1000 M MHz, and wherein each of the second lasers pulses is comprised of a series of third laser pulses having a third pulse repetition rate in a GHz range from 1 GHz to less than 1000 GHZ;
directing the first laser pulses into the top surface of the transparent material; and
focusing the first laser pulses to induce optical breakdown of the transparent material in a region within the transparent material that overlaps the bottom surface.
2 . The method of claim 1 , wherein pulsing the laser further comprises pulsing the laser through a lens combination to cause optical breakdown in air, in the absence of the transparent material.
3 . The method of claim 1 , wherein pulsing the laser further comprises pulsing the laser through a lens combination to induce spherical aberration in a laser beam resulting in an elongated depth of focus within the transparent material.
4 . The method of claim 1 , wherein pulsing the laser further comprises pulsing the laser through a diffractive optical combination to produce an elongated depth of focus within the transparent material.
5 . The method of claim 1 , wherein pulsing the laser further comprises pulsing the laser through an axicon optical element to produce an elongated depth of focus within the transparent material.
6 . The method of claim 1 , wherein the first pulse repetition rate is in a range of from 1 kHz to 100 kHz.
7 . The method of claim 1 , wherein the second pulse repetition rate is in a range of from 30 MHz to 80 MHz.
8 . The method of claim 1 , wherein pulsing the laser further comprises;
applying a first pulse spacing between each of the second lasers pulses, and
applying a second pulse spacing between each of the third laser pulses, wherein the second pulse spacing is less than the first pulse spacing.
9 . The method of claim 8 , wherein the second pulse spacing is in a range of from 250 femtoseconds to about 10 picoseconds.
10 . The method of claim 1 , wherein the third pulse repetition rate is in a range of from 1 GHz-to 10 GHz.
11 . The method of claim 1 , further comprising pulsing the series of third laser pulses at a pulse rate that is in a range of from about 250 femtoseconds to about 10 picoseconds.
12 . A method for scribing a transparent material with a laser, the method comprising:
providing relative movement between a laser and the transparent material, wherein the transparent material has a top surface and a bottom surface;
pulsing the laser to form a plurality of pulse bursts, wherein each pulse burst comprises a plurality of laser pulses having a pulse repetition rate in a range of from 1 GHz to less than 1000 GHz with a pulse spacing therebetween that is less than 1 nanosecond;
directing the laser into the top surface of the transparent material; and
focusing the laser pulses to induce optical breakdown of the transparent material in a region within the transparent material that overlaps the bottom surface, wherein each pulse burst is configured to annihilate a prior pulse burst in the transparent material and create free electrons through ionization.
13 . The method of claim 12 , wherein pulsing the laser further comprises pulsing the laser through a lens combination to cause optical breakdown in air, in the absence of the transparent material.
14 . The method of claim 13 , wherein focusing the laser further comprises pulsing the laser through a lens combination to induce spherical aberration in a laser beam resulting in an elongated depth of focus within the transparent material.
15 . The method of claim 13 , wherein pulsing the laser further comprises pulsing the laser through a diffractive optical combination to produce an elongated depth of focus within the transparent material.
16 . The method of claim 13 , wherein pulsing the laser further comprises pulsing the laser through an axicon optical element to produce an elongated depth of focus within the transparent material.
17 . The method of claim 13 , wherein the pulse spacing is in a range of from 250 femtoseconds to about 10 picoseconds.
18 . The method of claim 13 , wherein the pulse repetition rate is in a range of from 1 GHz to 10 GHz.