SYSTEM AND METHOD FOR SCANNING A PULSED LASER BEAM
System and method of photoaltering a region of a material using a pulsed laser beam. The method includes randomly scanning the pulsed laser beam in the region, and creating a separation between a first layer of the material and a second layer of the material at the region. The system includes a laser producing a pulsed laser beam, a controller transmitting a signal, and a scanner coupled to the controller. The scanner randomly scans the pulsed laser beam in the region in response to the signal.
1 . A method of photoaltering a region of a material using a pulsed laser beam, the method comprising the steps of:
randomly scanning the pulsed laser beam in the region; and
creating a separation between a first layer of the material and a second layer of the material at the region.
2 . The method of claim 1 , wherein the step of randomly scanning comprises:
actuating a mirror in at least one of a first direction and a second direction orthogonal to the first direction; and
directing the pulsed laser beam from the mirror to the region.
3 . The method of claim 2 , wherein the step of actuating a mirror comprises actuating the mirror via a piezo element.
4 . The method of claim 1 , wherein the step of randomly scanning comprises producing a plurality of scan spots in the region with the pulsed laser beam.
5 . The method of claim 1 , wherein the material has a surface, and wherein the step of randomly scanning comprises producing a plurality of sub-surface scan spots in the region with the pulsed laser beam.
6 . The method of claim 1 , further comprising aiming the pulsed laser beam at a predetermined location within the region prior to the step of randomly scanning, and wherein the step of randomly scanning comprises producing a spray of scan spots within the region and localized with respect to the predetermined location.
7 . The method of claim 1 , wherein the step of randomly scanning the pulsed laser beam comprises scanning the pulsed laser beam at a rate between about 30 MHz and about 1 GHz.
8 . The method of claim 1 , wherein the step of randomly scanning the pulsed laser beam comprises scanning the pulsed laser beam with a pulse energy of about 800 nJ/pulse.
9 . The method of claim 1 , wherein the step of randomly scanning the pulsed laser beam comprises scanning the pulsed laser beam with a pulse width of between about 300 picoseconds and about 10 femtoseconds.
10 . The method of claim 1 , wherein the step of randomly scanning the pulsed laser beam comprises scanning the pulsed laser beam at a wavelength between about 400 nm to about 3000 nm.
11 . The method of claim 1 , wherein the region has a periphery, and wherein the method further comprises, prior to the step of separating, scanning the pulsed laser beam along the periphery.
12 . A system for photoaltering a region of a material, the system comprising:
a laser configured to produce a pulsed laser beam;
a controller configured to transmit a signal; and
a scanner coupled to the controller, the scanner operable to randomly scan the pulsed laser beam in the region in response to the signal.
13 . The system of claim 12 , wherein the scanner is further operable to direct the pulsed laser beam to a focal plane, the focal plane having a first dimension and a second dimension orthogonal to the first dimension, and wherein the scanner comprises:
a mirror configured to receive the pulsed laser beam; and
a means for randomly displacing the mirror in at least one of the first dimension and the second dimension.
14 . The system of claim 12 , wherein the scanner comprises:
a mirror; and
a piezo element coupled to the mirror, the piezo element configured to displace the mirror in at least one of a first direction and a second direction orthogonal to the first direction.
15 . The system of claim 12 , wherein the pulsed laser beam has a pulse frequency selected from a range of about 30 MHz to about 1 GHz.
16 . The system of claim 12 , wherein the pulsed laser beam has a pulse energy less than or equal to about 800 nanojoules/pulse.
17 . The system of claim 12 , wherein the pulsed laser beam has a pulse width between about 300 picoseconds and about 10 femtoseconds.
18 . The system of claim 12 , wherein the pulsed laser beam has a wavelength between about 400 nm to about 3000 nm.
19 . The system of claim 12 , wherein the scanner is further configured to selectively single-point scan the pulsed laser beam in an absence of the signal.
20 . A method of forming a corneal flap of an eye, the method comprising the steps of:
randomly scanning a corneal region of the eye with a pulsed laser beam, the corneal region having a periphery; and
incising at least a portion of the periphery with the pulsed laser beam.
21 . The method of claim 19 , further comprising aiming the pulsed laser beam at a predetermined location within the corneal region prior to the step of randomly scanning, and wherein the step of randomly scanning comprises producing a plurality of scan spots at a predetermined depth in the corneal region with the pulsed laser beam, the plurality of scan spots being localized with respect to the predetermined location.