摘要:
An apparatus and a method for refractive surgery, in particular LASIK, make provision whereby the apex of the cornea is taken as a basis, as the ablation center, for the refractive procedure. For this purpose, the dependence of the position of the apex on properties of the pupil is determined in the case of the eye to be treated and, from this dependence, measured properties of the pupil are used to calculate the position of the ablation center during the refractive surgery.
摘要:
In certain embodiments, a device comprises a laser device and a control computer. The laser device directs a laser beam with laser energy through an outer portion of an eye to a target portion of the eye. The control computer receives an optical density measurement of the outer portion, determines the laser energy according to the optical density measurement, and instructs the laser device to direct the laser beam with the laser energy through the outer portion of the eye to the target portion of the eye.
摘要:
Embodiments of the invention provide a method and apparatus for laser-processing a material. In the embodiments, a diffraction-limited beam of pulsed laser radiation is diffracted by a diffraction device to generate a diffracted beam. The diffracted beam is subsequently focused onto the material and is controlled in time and space to irradiate the material at a target position with radiation from a set of radiation pulses of the diffracted beam so that each radiation pulse from the set of radiation pulses is incident at the target position with a cross-sectional portion of the diffracted beam, the cross-sectional portion including a local intensity maximum of the diffracted beam. The beam cross-sectional portions of at least a subset of the pulses of the set include each a different local intensity maxi-mum. In this way, a multi-pulse application for generating a photo-disruption at a target location of the material can be implemented.
摘要:
In certain embodiments, a system (10) comprises a laser source (20), one or more optical elements (24), a monitoring device (28), and a control computer (30). The laser source (20) emits one or more laser pulses. The optical elements (24) change a pulse length of the laser pulses, and the monitoring device (28) measures the pulse length of the laser pulses to detect the change in the pulse length. The control computer (30) receives the measured pulse length from the monitoring device (28), determines one or more laser parameters that compensate for the change in the pulse length, and controls the laser source (20) according to the laser parameters.
摘要:
The present invention relates to a laser apparatus, system, and method for determining a depth of a focus point of a laser beam. An interface device is coupleable to the laser apparatus and has an applanation element comprising a front surface and a back surface. A laser beam having a predefined shape is focussed through the applanation element at a focus point. A superimposed image of a spurious reflection, which is reflected from the front surface of the applanation element, with a standard reflection, which is reflected from the back surface of the applanation element, is detected. The spurious reflection is then filtered out of the superimposed image. Based on the remaining standard reflection, the depth of the focus point of the laser beam can be determined.
摘要:
A system for refractive ophthalmological surgery, in particular LASIK, has—in addition to the ablation laser and, where appropriate, further optical guidance means (18, 30)—a device (34) for optical coherence tomography as an integrated component, in order to make available results of measurement acquired with this device either for the purpose of representation on a display device and/or for the purpose of control of the ablation.
摘要:
The present invention relates to a method for generating a control program for ophthalmologic LASIK surgery, with which a pulsed laser system can be controlled for the photodisruptive cutting of a flap, having the following steps: obtaining empirical data, which relate to the effect in particular of flap shapes and ablation profiles on postoperative refractive results, obtaining measurement data relating to the eye to be treated, calculating an optimal cutting shape for the photodisruptive cutting of the flap by taking into account the said empirical data and the said measurement data, and generating the control program on the basis of the calculated cutting shape.
摘要:
A technique for optical coherence tomography is provided. As to a device aspect of the technique, an imaging device comprises a base defining a rotation axis, a scanning and focusing assembly mounted to the base for rotation about the rotation axis, and a drive unit for rotationally driving the scanning and focusing assembly about the rotation axis. The scanning and focusing assembly includes a focusing device for focusing a beam of imaging radiation to produce a focused beam of imaging radiation having a focus, a scanning member for scanning the beam of imaging radiation, and a controller coupled to the drive unit and the scanning member and configured to control the scanning member to cause movement of the focus along a predetermined trajectory with respect to the scanning and focusing assembly.
摘要:
In a process for optical coherence tomography a plurality of first OCT slice images, in each first slice image representing a different slice of an object, are recorded. Subsequently a reference figure that is representative of the three-dimensional contour of at least one structural feature of the object in a given three-dimensional coordinate system is ascertained by feature recognition of the at least one structural feature in the first slice images. Then a plurality of second OCT slice images, each second slice image representing a different slice of the object, are recorded. At least a fraction of the second slice images are displaced in the coordinate system until each second slice image is in feature overlap with the reference figure. Lastly, a set of three-dimensional OCT image data is generated at least from the feature-overlapped second slice images.
摘要:
A laser apparatus is controlled by a control program that operates to use laser radiation to generate an incision figure in the cornea of an eye, the incision figure including a an incision that bounds a corneal tissue volume. The control program operates to move the radiation focus in a radiation propogation direction successively in a plurality of superposed planes such that the radiation focus is moved without motion control in the propogation direction. The control program provides, for each plane, for a meandering scan path of the radiation focus that extends outside the tissue volume. The control program operates to allow through to the eye, in each plane, at least such radiation pulses that generate the first incision and to blank, in at least a fraction of the planes, at least a fraction of radiation pulses assigned to regions of the path that are at a distance from the incision.