ILLUMINATION VARIABILITY REDUCTION IN LASER TREATMENT SYSTEMS
Technologies are provided for laser treatment with reduced illumination variability. In some examples, a laser beam that creates a first illumination variation at a target site may be adjusted such that the laser beam orientation changes slightly while the laser beam is still being generated. The adjusted laser beam may create a second illumination variation at the target site, and because the laser beam orientation is different the first and second illumination variations may combine to form a combined illumination variation at the target site whose variability is less than the variability of the first or second illumination variations. The more-uniform combined illumination variation may then be used to treat the target site, for example via heat generation.
1 . A method for laser treatment with increased illumination uniformity, the method comprising:
generating a laser beam to create a first illuminated region at a first location of a target site;
adjusting the laser beam by oscillating the laser beam through an opto-electric interference to create a second illuminated region at a second location of the target site, such that:
the first and second regions at least partially overlap to form a combined illuminated region at the target site;
a uniformity of illumination of the combined illuminated region at the target site is greater than a uniformity of illumination of the first illuminated region at the target site; and
performing treatment at the target site using the combined illuminated region of the laser beam.
2 . The method of claim 1 , wherein adjusting the laser beam to create the second illuminated region at the second location of the target site further comprises:
oscillating the laser beam through one or more of an opto-acoustic interference or a mechanical interference.
3 . The method of claim 2 , wherein oscillating the laser beam comprises:
deflecting the laser beam to point from the first location to the second location.
4 . The method of claim 1 , wherein oscillating the laser beam through the opto-electric interference comprises:
oscillating the laser beam through an electro-optic device having an adjustable refractive index medium or generating a sinusoidal variation in the laser beam through a Pockels cell device.
5 . (canceled)
6 . The method of claim 1 , wherein generating the laser beam to create the first illuminated region at the first location of the target site comprises:
creating the first illuminated region at a portion of a retinal pigment epithelium (RPE) layer.
7 . (canceled)
8 . (canceled)
9 . The method of claim 1 , wherein generating the laser beam to create the first illuminated region at the first location of the target site comprises:
generating the laser beam for a duration of less than two microseconds.
10 . (canceled)
11 . The method of claim 1 , further comprising:
sweeping the adjusted laser beam in two orthogonal directions.
12 . (canceled)
13 . (canceled)
14 . A laser treatment system comprising:
a laser configured to generate a laser beam to create a first illuminated region at a first location of a target site;
an adjustment device coupled to the laser and configured to adjust the laser beam to create a second illuminated region at a second location of the target site by oscillating the laser beam through an opto-acoustic interference; and
a controller coupled to the laser and the adjustment device, the controller configured to control an operation of the adjustment device such that the first and second regions at least partially overlap to form a combined illuminated region at the target site and a uniformity of illumination of the combined illuminated region at the target site is greater than a uniformity of illumination of the first illuminated region at the target site.
15 .- 17 . (canceled)
18 . The system of claim 14 , wherein the adjustment device is configured to oscillate the laser beam with a sinusoidal variation in a first direction or by deflecting the laser beam to point from the first location to the second location.
19 . (canceled)
20 . The system of claim 18 , further comprising another adjustment device configured to oscillate the laser beam with a sinusoidal variation in a second direction that is orthogonal to the first direction.
21 . The system of claim 14 , further comprising a focus device configured to focus the adjusted laser beam.
22 . The system of claim 14 , wherein the target site is a portion of a retinal pigment epithelium (RPE) layer.
23 . The system of claim 22 , wherein, to create the second illuminated region at the second location of the target site, the adjustment device is configured to oscillate the laser beam to achieve a total deflection angle of less than 0.1 mrad for a deflector—RPE layer distance of greater than 10 centimeters.
24 . The system of claim 14 , wherein, to create the second illuminated region at the second location of the target site, the adjustment device is configured to oscillate the laser beam at a frequency of 0.6 MHz or greater.
25 . The system of claim 14 , wherein the laser is configured to generate the laser beam for a duration of less than two microseconds.
26 . (canceled)
27 . (canceled)
28 . A laser treatment system comprising:
a laser configured to generate a laser beam to create a first illuminated region at a first location of a target site and generate heat at the target site through the laser beam;
an electro-optic device comprising an adjustable refractive index medium, the electro-optic device coupled to the laser and configured to oscillate the laser beam in a first direction to create a second illuminated region at a second location of the target site; and
a controller coupled to the laser and the electro-optic device, the controller configured to control an operation of the electro-optic device such that the first and second regions at least partially overlap to form a combined illuminated region at the target site and a uniformity of illumination of the combined illuminated region at the target site is greater than a uniformity of illumination of the first illuminated region at the target site.
29 . (canceled)
30 . The system of claim 28 , wherein the electro-optic device is a Pockels cell device.
31 . The system of claim 30 , wherein the Pockels cell device comprises a crystal mixture of potassium tantalate and potassium niobate (KTN).
32 . The system of claim 31 , further comprising another electro-optic device configured to oscillate the laser beam with a sinusoidal variation in a second direction that is orthogonal to the first direction.
33 .- 35 . (canceled)
36 . The system of claim 28 , wherein, to create the second illuminated region at the second location of the target site, the electro-optic device is configured to oscillate the laser beam at a frequency of 0.6 MHz or greater.
37 .- 42 . (canceled)