MULTIPLE-SPOT LASER REFRACTIVE OPHTHALMIC SURGERY

• US 20100137849A1
• Filed: 04/22/2008
• Published: 06/03/2010
• Est. Priority Date: 04/26/2007
• Status: Active Grant

• Current Assignee: Carl Zeiss Meditec AG (Carl-Zeiss-Stiftung)
• Original Assignee: Carl Zeiss Meditec AG (Carl-Zeiss-Stiftung)
• Inventors: Wittig, Lars Christian, Stobrawa, Gregor, Bischoff, Mark, Wiechmann, Martin, Hanft, Marco
• Granted Patent: US 8,388,607 B2
• Time in Patent Office: Days
• US Class Current: 606/5
• CPC Class Codes: A61F 2009/00872 Cornea
• CPC Class Codes: A61F 9/008 using laser
• CPC Class Codes: A61F 9/00827 Refractive correction, e.g. lenticle
• CPC Class Codes: A61F 9/0084 Laser features or special beam parameters therefor
• CPC Class Codes: B23K 26/0604 by a combination of beams
• CPC Class Codes: B23K 26/0608 in the same heat affected zone [HAZ] B23K26/0613, B23K26/0619 take precedence
• CPC Class Codes: B23K 26/067 Dividing the beam into multiple beams, e.g. multifocusing
• CPC Class Codes: B23K 26/0676 into dependently operating sub-beams, e.g. an array of spots with fixed spatial relationship or for performing simultaneously identical operations
• CPC Class Codes: G02B 26/101 with both horizontal and vertical deflecting means, e.g. raster or XY scanners colour television using laser beams scanning a display screen H04N9/3129
• CPC Class Codes: G02B 27/0905 Dividing and/or superposing multiple light beams
• CPC Class Codes: G02B 27/0944 Diffractive optical elements, e.g. gratings, holograms gratings per se G02B5/18; holograms used as optical elements per se G02B5/32
• CPC Class Codes: G02B 27/0977 Reflective elements

Abstract

An apparatus for material processing by laser radiation, including a laser source which emits a processing beam, and a beam path for focusing and scanning, the beam path focusing the processing beam into a processing volume and shifting the position of the focus therein. A beam splitting device generates several foci in the processing volume and the beam splitting device splits the processing beam up into a primary beam and at least one secondary beam and leaves the cross section of the beam in a pupil plane of the beam path unchanged during said division and introduces an angle of separation between the primary and secondary beams, so that these beams expand in the beam path in directions which differ by the angle of separation.

Claims

1-11. -11. (canceled)

12. An apparatus for refractive ophthalmic surgery by laser radiation, said apparatus comprising:

a source of radiation which emits a processing beam;

a beam path for focusing and scanning, said beam path focusing the processing beam into a cornea of an eye and shifting a position of a focus therein;

a beam splitting device that generates several foci in the cornea, wherein the beam splitting device divides the processing beam into a primary beam and at least one secondary beam and leaves a cross section of the beam unchanged during said division, so that the primary and secondary beams have the same cross section as the processing beam which is incident on the beam splitting device;

wherein the beam-splitting device introduces an angle of separation between the primary and secondary beams, so that the primary and secondary beams expand in the beam path in directions which differ by the angle of separation; and

further comprising a contact glass which induces a pre-defined geometric boundary surface at the cornea.

13. The apparatus as claimed in claim 12, wherein the beam splitting device does not have a focusing effect.

14. The apparatus as claimed in claim 12, wherein the beam splitting device is arranged close to a pupil in the beam path.

15. The apparatus as claimed in claim 12, wherein the beam splitting device is arranged anterior to scanning elements.

16. The apparatus as claimed in claim 12, wherein the beam splitting device can be activated and de-activated.

17. The apparatus as claimed in claim 12, wherein the beam splitting device comprises a diffractively working element.

18. The apparatus as claimed in claim 17, wherein said element is a phase grating.

19. The apparatus as claimed in claim 12, wherein the beam splitting device comprises an element which comprises wedges and planar plates.

20. The apparatus as claimed in claim 12, wherein the beam splitting device rotates the at least one secondary beam around the primary beam.

21. The apparatus as claimed in claim 20, further comprising a control unit, which controls the rotation synchronously with the focus position adjustment.

22. The apparatus as claimed in claim 20, wherein the beam splitting device comprises a rotating grating or a rotating segmented plate.

23. The apparatus as claimed in claim 21, wherein the beam splitting device comprises a rotating grating or a rotating segmented plate.

24. The apparatus as claimed in claim 20, wherein the beam splitting device separately directs the at least one secondary beam to a scanning device which deflects the at least one secondary beam in a controlled manner before the beam splitting device superimposes the primary beam again on the thus-deflected at least one secondary beam.

25. The apparatus as claimed in claim 21, wherein the beam splitting device separately directs the at least one secondary beam to a scanning device which deflects the at least one secondary beam in a controlled manner before the beam splitting device superimposes the primary beam again on the thus-deflected at least one secondary beam.