Device For Treating Eye Tissue Using Laser Pulses

Abstract

An ophthalmic device for treating eye tissue using laser pulses comprises a projection optical unit for focused projection of the laser pulses and a scanning device, with a movable mirror, arranged downstream from the projection optical unit, for deflecting the laser pulses projected by the projection optical unit in at least one deflection direction. The ophthalmic device moreover comprises an optical correction element arranged downstream of the scanning device, which correction element is configured to image, in a focused manner, the laser pulses deflected by the scanning device on an intended treatment area in the eye tissue. The optical correction element renders it possible to therefore correct image field curvatures caused by the scanning device arranged downstream from the projection optical unit and, for example, image the deflected laser pulses in focus onto a plane.

What is claimed is: 
     
         1 . An ophthalmic device for treating eye tissue using laser pulses, comprising:
 a laser source configured to produce the laser pulses;   an optical focusing unit configured to focus the laser pulses;   a scanning device, with a movable mirror, arranged downstream from the optical focusing unit, and configured to deflect the laser pulses from the optical focusing unit in at least one deflection direction, whereby moving the movable mirror causes an image field curvature; and   an optical correction element arranged downstream of the scanning device and configured to correct the image field curvature, by imaging, in a focused manner, the laser pulses deflected by the scanning device on an intended treatment plane in the eye tissue,   wherein the optical correction element is configured to image the laser pulses deflected by the scanning device in a focused manner on the intended treatment plane for producing a planar cut in the eye tissue.   
     
     
         2 . The ophthalmic device of  claim 1 , wherein the optical correction element comprises a lens element, the movable mirror has a pivot point, and the lens element has a lens surface equidistant to the pivot point of the movable mirror. 
     
     
         3 . The ophthalmic device of  claim 1 , wherein the optical correction element comprises a lens configured to image, in the focused manner, the laser pulses deflected by the scanning device onto a focus with defined spot quality, the defined spot quality comprising at least one of: size of a spot, shape of the spot, diameter of the spot across a projection direction, or length of the spot in the projection direction. 
     
     
         4 . The ophthalmic device of  claim 1 , wherein the optical correction element is configured as a contact body, wherein the contact body has a flat contact surface or a curved contact surface. 
     
     
         5 . The ophthalmic device of  claim 1 , wherein the ophthalmic device comprises a patient interface device configured to be fastened to the eye of a patient, and the optical correction element is securely or detachably connected to the patient interface device. 
     
     
         6 . The ophthalmic device of  claim 1 , wherein the scanning device is configured to move the moveable mirror about a pivot point lying on an optical axis of the optical focusing unit and on a surface of the movable mirror. 
     
     
         7 . The ophthalmic device of  claim 1 , wherein the scanning device comprises a plurality of linear drives coupled to the movable mirror, and the ophthalmic device comprises a control module configured to control the plurality of linear drives to rotate the movable mirror about a pivot point lying on an optical axis of the optical focusing unit and on a surface of the movable mirror. 
     
     
         8 . An ophthalmic device for treating eye tissue using laser pulses, comprising:
 a laser source configured to output a laser beam with the laser pulses;   an optical focusing unit having a focal length for focusing the laser pulses;
 a scanning device, with a movable mirror, arranged downstream from the optical focusing unit, the movable mirror having a mirror surface configured to deflect the laser pulses from the optical focusing unit in at least one deflection direction; 
 a drive system comprising a plurality of linear drives coupled to the movable mirror and configured to rotate the movable mirror around a pivot point, the pivot point lying on the mirror surface and on an optical axis of the optical focusing unit, and the pivot point being displaceable on the optical axis; and 
 a circuit configured to control the plurality of linear drives to perform translational movements for directing each of the laser pulses onto a respective target point in the eye tissue, by:
 displacing, using the translational movements of the plurality of linear drives, the pivot point to a particular point on the optical axis, the particular point on the optical axis having a distance, with respect to the focal length of the optical focusing unit, equal to the distance between the particular point and the respective target point in the eye tissue; and 
 rotating, using the translational movements of the plurality of linear drives, the movable mirror around the pivot point such that the mirror deflects the laser pulses focused by the optical focusing unit in the at least one deflection direction of the respective target point in the eye tissue. 
 
   
     
     
         9 . The ophthalmic device of  claim 8 , wherein the circuit is configured to control the plurality of linear drives to perform the translational movements to direct the laser pulses onto target points of a treatment line in the eye tissue. 
     
     
         10 . The ophthalmic device of  claim 8 , wherein the circuit is configured to control the plurality of linear drives to perform the translational movements to direct the laser pulses onto target points of a treatment surface in the eye tissue. 
     
     
         11 . The ophthalmic device of  claim 8 , wherein the circuit is configured to control the plurality of linear drives to perform the translational movements to direct the laser pulses onto target points of a three-dimensional treatment surface in the eye tissue. 
     
     
         12 . The ophthalmic device of  claim 8 , wherein the ophthalmic device comprises a patient interface device configured to be fastened to an eye of a patient; and the scanning device is configured to be moved out of a beam path to the eye in a state where the patient interface device is fastened to the eye. 
     
     
         13 . The ophthalmic device of  claim 8 , wherein the ophthalmic device further comprises a correction system configured to change the focal length, depending on the deflection direction of the laser pulses, using an optical element arranged upstream from the optical focusing unit. 
     
     
         14 . The ophthalmic device of  claim 13 , wherein the correction system comprises a divergence modulator arranged upstream from the optical focusing unit, the divergence modulator being configured to modify divergence of the laser beam depending on the deflection direction of the laser pulses. 
     
     
         15 . The ophthalmic device of  claim 14 , wherein the divergence modulator comprises at least one item from the following list: two optical lenses arranged in series, wherein at least one of the optical lenses is coupled to a movement driver in a manner displaceable on an optical axis for modulating the divergence of the laser beam; a deformable lens; a deformable mirror element; a spatial light modulator for modulating the wavefront of the laser beam; an area light modulator for modulating reflection angles at a plurality of points of a reflection surface; a refraction modulator for modulating the refractive index of an optical element at a plurality of points in the cross section of the beam path; or an amplitude modulator for modulating the amplitude at a plurality of points in the cross section of the beam path of the laser beam. 
     
     
         16 . The ophthalmic device of  claim 8 , wherein the ophthalmic device further comprises a zoom system arranged upstream from the optical focusing unit or integrated into the optical focusing unit, the zoom system being configured to change the focal length depending on the deflection direction of the laser pulses. 
     
     
         17 . A method of treating eye tissue using laser pulses, comprising:
 outputting, by a laser source, a pulsed laser beam with laser pulses;   focusing the laser pulses, by an optical focusing unit having a focal length;
 deflecting, by a scanning device comprising a movable mirror having a mirror surface, the focused laser pulses in at least one deflection direction; 
 controlling, by a circuit, a plurality of linear drives, coupled to the movable mirror, to perform translational movements for directing each of the laser pulses onto a respective target point in the eye tissue, by:
 displacing, by the translational movements of the plurality of linear drives, a pivot point, lying on the mirror surface, to a particular point on an optical axis of the optical focusing unit, the particular point on the optical axis having a distance, with respect to the focal length of the optical focusing unit, equal to the distance between the particular point and the respective target point in the eye tissue; and 
 rotating, by the translational movements of the plurality of linear drives, the movable mirror around the pivot point such that the movable mirror deflects the focused laser pulses in the at least one deflection direction of the respective target point. 
 
   
     
     
         18 . The method of  claim 17 , comprising the circuit controlling the plurality of linear drives to perform the translational movements to direct the laser pulses onto target points of at least one of: a treatment line in the eye tissue, a treatment surface in the eye tissue, or a three-dimensional treatment surface in the eye tissue. 
     
     
         19 . A computer program product comprising a non-transient computer-readable medium having stored thereon computer program code for controlling at least one processor of an ophthalmological device which comprises a laser source configured to output a laser beam with laser pulses, an optical focusing unit having a focal length configured to focus each of the laser pulses, a scanning device with a movable mirror having a mirror surface configured to deflect the laser pulses focused by the optical focusing unit in at least one deflection direction, whereby the computer program code is configured to control the at least one processor such that the at least one processor controls a plurality of linear drives, coupled to the movable mirror, to perform translational movements for directing each of the laser pulses onto a respective target point in eye tissue, by:
 displacing, by the translational movements of the plurality of linear drives, a pivot point, lying on the mirror surface, to a particular point on an optical axis of the optical focusing unit, the particular point on the optical axis having a distance, with respect to the focal length of the optical focusing unit, equal to the distance between the particular point and the respective target point in the eye tissue, and   rotating, by the translational movements of the plurality of linear drives, the movable mirror around the pivot point such that the movable mirror deflects the focused laser pulses in the at least one deflection direction of the respective target point in the eye tissue.   
     
     
         20 . The computer program product of  claim 19 , wherein the computer program code is configured to control the at least one processor such that the at least one processor controls the plurality of linear drives to perform the translational movements to direct the laser pulses onto target points of at least one of: a treatment line in the eye tissue, a treatment surface in the eye tissue, or a three-dimensional treatment surface in the eye tissue.