WO1997043078A1 - Process and device for removal of material with a laser beam - Google Patents

Process and device for removal of material with a laser beam Download PDF

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Publication number
WO1997043078A1
WO1997043078A1 PCT/EP1997/002331 EP9702331W WO9743078A1 WO 1997043078 A1 WO1997043078 A1 WO 1997043078A1 EP 9702331 W EP9702331 W EP 9702331W WO 9743078 A1 WO9743078 A1 WO 9743078A1
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WO
WIPO (PCT)
Prior art keywords
laser beam
axis
cross
intensity profile
short
Prior art date
Application number
PCT/EP1997/002331
Other languages
German (de)
French (fr)
Inventor
Fredy Strohm
Peter Oesterlin
Berthold Burghardt
Henning Schmidt
Hans-Jürgen Kahlert
Original Assignee
Aesculap-Meditec Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Aesculap-Meditec Gmbh filed Critical Aesculap-Meditec Gmbh
Priority to AU28934/97A priority Critical patent/AU2893497A/en
Publication of WO1997043078A1 publication Critical patent/WO1997043078A1/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/064—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
    • B23K26/0648—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms comprising lenses
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F9/00—Methods or devices for treatment of the eyes; Devices for putting-in contact lenses; Devices to correct squinting; Apparatus to guide the blind; Protective devices for the eyes, carried on the body or in the hand
    • A61F9/007—Methods or devices for eye surgery
    • A61F9/008—Methods or devices for eye surgery using laser
    • A61F9/00802—Methods or devices for eye surgery using laser for photoablation
    • A61F9/00814—Laser features or special beam parameters therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/064—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F9/00—Methods or devices for treatment of the eyes; Devices for putting-in contact lenses; Devices to correct squinting; Apparatus to guide the blind; Protective devices for the eyes, carried on the body or in the hand
    • A61F9/007—Methods or devices for eye surgery
    • A61F9/008—Methods or devices for eye surgery using laser
    • A61F2009/00861—Methods or devices for eye surgery using laser adapted for treatment at a particular location
    • A61F2009/00872—Cornea

Definitions

  • the invention relates to a method and a device for removing material from the surface of an object, in particular for ophthalmological shaping of lenses, by means of a pulsed laser beam directed at the object and having a cross section with a longer axis and a shorter axis, and the like
  • Intensity profile in the direction of the long axis is different from its at least approximately Gaussian intensity profile in the direction of the short axis, and its cross-section is significantly smaller than the surface to be removed, the laser beam in the direction of the short cross-sectional axis while maintaining the Gaussian intensity profile in the direction the short cross-sectional axis is so successively guided over the surface to be removed that successive laser pulses are overlapping and offset from one another.
  • Such a method and such a device are known from DE 41 41 890 AI.
  • Excimer lasers emit coherent UV radiation of high intensity and are used in particular in industrial production, medicine and in research.
  • a particular application of the present invention is the ophthalmological shape correction of lenses by means of ablation by excimer laser radiation.
  • the laser beam has no uniform intensity distribution over its cross section.
  • the laser beam emitted by the excimer laser typically has dimensions of approximately 10 x 30 mm. According to this rectangular cross section of the laser beam, one speaks of a long and a short axis. In the direction of the long axis, the intensity profile of the laser beam is approximately trapezoidal with fluctuations in intensity (so-called "flat top”). In the direction of the short axis, the excimer laser beam has an intensity profile that corresponds approximately to a Gaussian curve.
  • the prior art knows a number of optical devices for the homogenization of, in particular, excimer laser beams, such as DE-A-42 20 705 (corresponding to US Pat. No. 5,414,559).
  • Homogenizing optics serve to distribute the intensity of a laser beam over its cross-section as uniformly as possible, that is, to compensate for differences in intensity.
  • JP 07027993 A, EP 0 232 037 and EP 0 100 242 A2 also show homogenizing optics, some with anamorphic arrangements.
  • An anamorphic image is an optical image in which the image scale or the image size is different in two sections (directions) perpendicular to each other. In the case of the excimer laser beams explained above, the cuts which are perpendicular to one another are generally in the direction of the long and short axes.
  • DE 42 32 690 C1 also describes an apparatus and a method for ophthalmological shape correction of a lens using excimer laser beams, in which the radiation is concentrated in a beam whose cross section is smaller than that of one when it hits the lens surface Aperture released lens surface.
  • the bundle of rays is moved in such a way that the entire lens surface released by the diaphragm is irradiated by successive radiation pulses striking the lens surface.
  • the beam of rays is moved between successive radiation pulses only to such an extent that the areas of the lens surface that are hit by successive radiation pulses on the lens surface partially overlap.
  • the invention is based on the object of providing a method and a device of the type mentioned at the outset which deliver improved results with as little effort as possible with regard to ablation and which permit the most versatile use possible.
  • the intensity profile of the laser beam is in Direction of the long cross-sectional axis is homogenized by means of homogenizing optics.
  • the imaging optics effective in the direction of the short axis and the imaging and homogenization optics effective in the direction of the long axis are anamorphic, so that the desired parameters of the laser beam can be set independently of one another in both axis directions.
  • a further preferred embodiment of the invention provides that the laser beam is imaged by means of an imaging optics in a plane in which the beam properties (parameters) of the imaged laser beam are set, and that the beam from this plane is projected onto the one to be ablated by means of further imaging optics Surface is mapped.
  • this plane which can also be referred to as a "fictitious mask plane"
  • the parameters of the laser beam namely in particular its dimensions in the direction of the long and short axes and its homogeneity, can be set independently of one another for both axis directions and the beam is then included mapped these set parameters on the working level (i.e. the surface to be removed). There is no need to arrange a mask in the "fictitious mask plane".
  • a mask is placed directly in front of the eye and the radiation spot is guided over the mask by means of a scanner, as described in DE 42 32 690 C1.
  • the dimensions of the mask can be changed in order to effect a certain ablation on the cornea of the eye.
  • the scanner moves the radiation spot in the direction of the short cross-sectional axis over the opening of the mask arranged in front of the eye.
  • a mask can be arranged in the "fictitious mask plane" instead of in front of the eye.
  • the opening of this mask will then homogeneously illuminated with the laser beam, ie the mask is placed in the beam path in such a way that a particularly homogeneous area of the laser beam is let through.
  • the scanner arranged between mask and eye in this exemplary embodiment then moves the radiation spot over the cornea to be removed.
  • the radiation spot on the cornea is preferably reduced to dimensions of 1 to 2 mm (by interaction of the mask and the optical imaging means).
  • the beam always has the same beam parameters (in particular its dimensions and its homogeneity) in the plane of the surface to be removed.
  • the homogenizing optics make the parameters of the laser beam in the plane of the surface to be removed largely independent of the quality of the beam emitted by the laser.
  • the entire energy emitted by the laser can also be concentrated on the surface to be processed.
  • the radiation intensity received by the object per unit area is homogeneous apart from fluctuations of at most 10% (in both directions).
  • the invention also allows the energy of the laser pulses to be set in the desired manner in a simple manner by means of attenuators, without the dimensions of the beam being influenced.
  • FIG. 1 schematically shows an imaging optical system which is effective in the direction of the short cross-sectional axis of an excimer laser beam and
  • Fig. 2 shows an imaging and homogenizing optics, which is effective in the direction of the long axis of the same excimer laser beam.
  • Figures 1 and 2 show the same imaging and homogenizing optics in two views that are at right angles to each other.
  • the optics do not bring about homogenization in the direction of the short axis, rather the intensity profile as it is emitted by the laser (not shown) is retained, for example a Gaussian profile. In contrast, homogenization takes place in the direction of the long axis.
  • the laser beam 10 emitted by the excimer laser first enters a homogenizing optics from elements 12 and 14.
  • the homogenizing optics also consist of two rows of cylindrical lenses (see FIG. 2) and are known as such (US Pat. No. 5,414,559).
  • other homogenizing optics known as such can also be used, cf. for example DE-OS 42 20 705, DE 38 29 728 and DE 38 41 045.
  • the two parallel rows 12, 14 of cylindrical lenses are oriented such that they bring about homogenization only in the direction of the long axis, while the beam in the direction of the short axis (FIG. 1) undergoes no homogenization.
  • a collecting lens 16 is arranged in the beam path behind the homogenizing optics 12, 14, which has a collecting effect only in the direction of the long axis.
  • Another converging lens 18 in the beam path only has a collective effect with regard to the short axis.
  • a converging lens 20 arranged behind it in the beam path only acts in the direction of the long axis.
  • optical elements with the reference numerals 12, 14 and 16 form an overall homogenizing optical system with respect to the long axis of the laser beam profile.
  • the converging lens 18 acts only with respect to the short axis, that is to say it is designed as a cylindrical lens (cylinder shape perpendicular to the plane of the drawing) and is used to adjust the beam dimension in the direction of the short axis, the Gaussian-like beam profile being retained.
  • the converging lens 20 focusing with respect to the long axis is also designed as a cylindrical lens.
  • the scanner 26 can be moved in particular in the direction of the short axis, so that no further homogenizing optics which would be effective in the direction of this axis are required.
  • the beam is successively moved overlapping over the surface 30 to be machined, the overlap being selected such that there is also extensive homogenization of the intensity in this direction with intensity fluctuations of less than 10%.
  • the reference numeral 22 in FIGS. 1 and 2 denotes a plane in which the parameters of the laser beam, namely in particular its dimensions in both axial directions and its homogeneity, are set by means of the optical elements arranged in front of it in the beam path.
  • this setting is possible in both axial directions independently of one another, i.e. for a given system, the optical elements can be selected so that the desired beam parameters are present in the plane 22 for both axial directions.
  • This level 22 is referred to above as the "fictitious mask level".
  • Imaging optics images the beam with the parameters set from the plane 22 into the plane of the surface 30 to be processed. There is no need for a mask.
  • the scanning head 26 moves the beam on the surface 30 to be removed in the desired manner (see above).
  • a mask can also be arranged in the plane 22, the opening of which is schematically identified by the reference numeral 28.
  • This mask can let through a certain section of the laser beam, which is selected, for example, from the point of view of optimal homogeneity. Then the opening area of the mask is imaged on the surface 30 to be processed with the described optics.

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  • Optics & Photonics (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Plasma & Fusion (AREA)
  • Mechanical Engineering (AREA)
  • Ophthalmology & Optometry (AREA)
  • Surgery (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Vascular Medicine (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Laser Beam Processing (AREA)
  • Laser Surgery Devices (AREA)

Abstract

The invention relates to a process and a device for the removal of material from the surface (30) of an object. Said process and device are used, in particular, for ophthalmological shaping of lenses using a laser beam having a cross-section with a long axis and a short axis. The intensity profile in the direction of the short axis is substantially gaussian-shaped. The laser beam is gradually directed in the direction of the short cross-sectional axis maintaining the gaussian-shaped intensity profile across the surface (30) to be removed, and successive laser pulses overlap each other. The intensity profile of the laser beam in the direction of the long cross-sectional axis is homogenised.

Description

Verfahren und Vorrichtung zum Abtragen von Material mit einem Laserstrahl Method and device for removing material with a laser beam
Die Erfindung betrifft ein Verfahren und eine Vorrichtung zum Abtragen von Material von der Oberfläche eines Objektes, ins¬ besondere zum ophthalmologischen Formen von Linsen, mittels eines auf das Objekt gerichteten gepulsten Laserstrahles, der einen Querschnitt mit einer längeren Achse und einer kürzeren Achse hat und dessen Intensitätsprofil in Richtung der langen Achse verschieden ist von seinem zumindest annähernd gaußför- migen Intensitätsprofil in Richtung der kurzen Achse, und dessen Querschnitt deutlich kleiner ist als die abzutragende Oberfläche, wobei der Laserstrahl in Richtung der kurzen Querschnittsachse unter Beibehaltung des gaußförmigen Inten¬ sitätsprofils in Richtung der kurzen Querschnittsachse so sukzessive über die abzutragende Oberfläche geführt wird, daß aufeinanderfolgende Laserpulse einander überlappend und zuein¬ ander versetzt sind. Ein solches Verfahren und eine solche Vorrichtung sind aus der DE 41 41 890 AI bekannt.The invention relates to a method and a device for removing material from the surface of an object, in particular for ophthalmological shaping of lenses, by means of a pulsed laser beam directed at the object and having a cross section with a longer axis and a shorter axis, and the like Intensity profile in the direction of the long axis is different from its at least approximately Gaussian intensity profile in the direction of the short axis, and its cross-section is significantly smaller than the surface to be removed, the laser beam in the direction of the short cross-sectional axis while maintaining the Gaussian intensity profile in the direction the short cross-sectional axis is so successively guided over the surface to be removed that successive laser pulses are overlapping and offset from one another. Such a method and such a device are known from DE 41 41 890 AI.
Excimerlaser emittieren kohärente UV-Strahlung hoher Intensi¬ tät und werden insbesondere in der industriellen Fertigung, der Medizin und in der Forschung eingesetzt. Eine besondere An¬ wendung der vorliegenden Erfindung ist die ophthalmologische Formkorrektur von Linsen mittels Ablation durch Excimer-Laser- strahlung.Excimer lasers emit coherent UV radiation of high intensity and are used in particular in industrial production, medicine and in research. A particular application of the present invention is the ophthalmological shape correction of lenses by means of ablation by excimer laser radiation.
Der vom Excimerlaser (im wesentlichen unverarbeitet) emittierte Laserstrahl hat in der Regel keine gleichförmige Intensitäts¬ verteilung über seinen Querschnitt. Der vom Excimerlaser abgegebene Laserstrahl hat typischerweise Abmessungen von etwa 10 x 30 mm. Entsprechend diesem rechteckförmigen Querschnitt des Laserstrahls spricht man von einer langen und einer kurzen Achse. In Richtung der langen Achse ist das Intensitätsprofil des Laserstrahls etwa trapezförmig mit Intensitätsschwankungen (sogenanntes "flat top") . In Richtung der kurzen Achse hat der Excimer-Laserstrahl ein Intensitätsprofil, das etwa einer Gauß-Kurve entspricht.The one emitted by the excimer laser (essentially unprocessed) As a rule, the laser beam has no uniform intensity distribution over its cross section. The laser beam emitted by the excimer laser typically has dimensions of approximately 10 x 30 mm. According to this rectangular cross section of the laser beam, one speaks of a long and a short axis. In the direction of the long axis, the intensity profile of the laser beam is approximately trapezoidal with fluctuations in intensity (so-called "flat top"). In the direction of the short axis, the excimer laser beam has an intensity profile that corresponds approximately to a Gaussian curve.
Der Stand der Technik kennt eine Reihe von optischen Vorrich¬ tungen zum Homogenisieren von insbesondere Excimer-Laserstrah- len, so die DE-A-42 20 705 (entsprechend US-Patent 5,414,559). Homogenisieroptiken dienen dazu, die Intensität eines Laser¬ strahls über seinen Querschnitt möglichst gleichförmig zu verteilen, also Intensitätsunterschiede auszugleichen. Auch die JP 07027993 A, die EP 0 232 037 und die EP 0 100 242 A2 zeigen Homogenisieroptiken, teilweise mit anamorphotischen Anordnungen. Eine anamorphotische Abbildung ist eine optische Abbildung, bei der der Abbildungsmaßstab bzw. die Bildgröße in zwei senkrecht zueinander stehenden Schnitten (Richtungen) unterschiedlich ist. Bei den vorstehend erläuterten Excimer- laserstrahlen sind die genannten senkrecht zueinander stehen¬ den Schnitte in der Regel in Richtung der langen und kurzen Achsen.The prior art knows a number of optical devices for the homogenization of, in particular, excimer laser beams, such as DE-A-42 20 705 (corresponding to US Pat. No. 5,414,559). Homogenizing optics serve to distribute the intensity of a laser beam over its cross-section as uniformly as possible, that is, to compensate for differences in intensity. JP 07027993 A, EP 0 232 037 and EP 0 100 242 A2 also show homogenizing optics, some with anamorphic arrangements. An anamorphic image is an optical image in which the image scale or the image size is different in two sections (directions) perpendicular to each other. In the case of the excimer laser beams explained above, the cuts which are perpendicular to one another are generally in the direction of the long and short axes.
Bei der eingangs genannten DE 41 41 890 AI, von der die vor¬ liegende Erfindung ausgeht, sollen Homogenisieroptiken ver¬ mieden werden. Um auch in Richtung der kurzen Querschnittsach¬ se des Excimerlaserstrahls eine weitgehende Homogenisierung der auf die abzutragende Oberfläche aufgebrachten Strahlungs¬ energie zu erreichen, wird bei diesem Stand der Technik der Laserstrahl sukzessive mittels eines Abtasters so in Richtung der kurzen Querschnittsachse über die abzutragende Oberfläche bewegt, daß aufeinanderfolgende Laserpulse einander überlap¬ pend zueinander versetzt sind. Die Überlappung zweier benach- barter versetzter Laserpulse ist so, daß die Überlagerung der gaußförmigen Intensitätsprofile in der Summe eine gleichmäßi¬ gere Intensitätsverteilung ergibt.In the aforementioned DE 41 41 890 AI, from which the present invention is based, homogenizing optics are to be avoided. In order to achieve extensive homogenization of the radiation energy applied to the surface to be removed, also in the direction of the short cross-sectional axis of the excimer laser beam, in this prior art the laser beam is successively moved by means of a scanner in the direction of the short cross-sectional axis over the surface to be removed, that successive laser pulses are offset from one another in an overlapping manner. The overlap of two neighboring The laser pulse is offset in such a way that the superimposition of the Gaussian intensity profiles results in a uniform intensity distribution overall.
Die DE 42 32 690 Cl beschreibt ebenfalls eine Vorrichtung und ein Verfahren zur ophthalmologischen Formkorrektur einer Linse unter Verwendung von Excimerlaserstrahlen, bei denen die Strah¬ lung in einem Strahlenbündel konzentriert wird, dessen Quer¬ schnitt bei Auftreffen auf die Linsenoberfläche kleiner ist als die von einer Blende freigegebene Linsenoberfläche. Dabei wird das Strahlenbündel so bewegt, daß durch nacheinander auf die Linsenoberfläche auftreffende Strahlungspulse die gesamte von der Blende freigegebene Linsenoberfläche bestrahlt wird. Das Strahlenbündel wird zwischen aufeinanderfolgenden Strah¬ lungspulsen nur so weit bewegt, daß sich die von nacheinander auf der Linsenoberfläche auftreffenden Strahlungspulsen ge¬ troffenen Bereiche der Linsenoberfläche teilweise überlappen.DE 42 32 690 C1 also describes an apparatus and a method for ophthalmological shape correction of a lens using excimer laser beams, in which the radiation is concentrated in a beam whose cross section is smaller than that of one when it hits the lens surface Aperture released lens surface. The bundle of rays is moved in such a way that the entire lens surface released by the diaphragm is irradiated by successive radiation pulses striking the lens surface. The beam of rays is moved between successive radiation pulses only to such an extent that the areas of the lens surface that are hit by successive radiation pulses on the lens surface partially overlap.
Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren und eine Vorrichtung der eingangs genannten Art bereitzustellen, die mit möglichst geringem Aufwand bezüglich der Ablation verbesserte Ergebnisse liefern und eine möglichst vielsei¬ tige Anwendung ermöglichen.The invention is based on the object of providing a method and a device of the type mentioned at the outset which deliver improved results with as little effort as possible with regard to ablation and which permit the most versatile use possible.
Die Erfindung sieht bei einem System, bei dem der Laserstrahl in Richtung der kurzen Querschnittsachse unter Beibehaltung des zumindest annähernd gaußförmigen Intensitätsprofils so nacheinander über die abzutragende Oberfläche geführt wird, daß aufeinanderfolgende Laserpulse einander überlappend und zueinander versetzt sind, vor, daß das Intensitätsprofil des Laserstrahls in Richtung der langen Querschnittsachse mittels einer Homogenisieroptik homogenisiert wird.In a system in which the laser beam is guided in succession over the surface to be removed in the direction of the short cross-sectional axis while maintaining the at least approximately Gaussian intensity profile in such a way that successive laser pulses are overlapping and offset from one another, the intensity profile of the laser beam is in Direction of the long cross-sectional axis is homogenized by means of homogenizing optics.
Es hat sich gezeigt, daß beste ophthalmologische Ablationser- gebnisse besonders dann erreicht werden, wenn die genannte Homogenisierung so eingestellt wird, daß das Intensitätsprofil des Laserstrahls in Richtung der langen Querschnittsachse möglichst annähernd Rechteckform hat mit Intensitätsschwankun¬ gen, die nicht größer sind als 10%.It has been shown that the best ophthalmic ablation results are achieved in particular if the homogenization mentioned is set in such a way that the intensity profile of the laser beam in the direction of the long cross-sectional axis is approximately as rectangular as possible with intensity fluctuations that are not greater than 10%.
Gemäß einer bevorzugten Ausgestaltung der Erfindung sind die in Richtung der kurzen Achse wirksamen Abbildungsoptiken und die in Richtung der langen Achse wirksamen Abbildungs- und Homogenisieroptiken anamorphotisch, so daß die gewünschten Parameter des Laserstrahls in beiden Achsrichtungen unabhän¬ gig voneinander einstellbar sind.According to a preferred embodiment of the invention, the imaging optics effective in the direction of the short axis and the imaging and homogenization optics effective in the direction of the long axis are anamorphic, so that the desired parameters of the laser beam can be set independently of one another in both axis directions.
Eine weitere bevorzugte Ausgestaltung der Erfindung sieht vor, daß der Laserstrahl mittels einer Abbildungsoptik in eine Ebe¬ ne abgebildet wird, in der die Strahleigenschaften (Parameter) des abgebildeten Laserstrahls eingestellt werden, und daß der Strahl aus dieser Ebene mittels einer weiteren Abbildungsoptik auf die abzutragende Oberfläche abgebildet wird. In dieser genannten Ebene, die auch als "fiktive Maskenebene" bezeichnet werden kann, können die Parameter des Laserstrahls, nämlich insbesondere seine Abmessungen in Richtung der langen und kurzen Achsen und seine Homogenität, für beide Achsrichtungen unabhängig voneinander eingestellt werden und der Strahl wird dann mit diesen eingestellten Parametern auf die Arbeitsebene (also die abzutragende Oberfläche) abgebildet. Dabei braucht in der "fiktiven Maskenebene" keine Maske angeordnet zu wer¬ den. Eine Maske wird unmittelbar vor dem Auge angeordnet und mittels eines Abtasters (Scanners) wird der Strahlungsfleck über die Maske geführt, wie es in DE 42 32 690 Cl beschrieben ist. Die Maske kann in ihren Abmessungen verändert werden, um an der Hornhaut des Auges eine bestimmte Ablation zu bewirken. Der Abtaster (Scanner) bewegt den Strahlungsfleck in Richtung der kurzen Querschnittsachse über die Öffnung der vor dem Auge angeordneten Maske.A further preferred embodiment of the invention provides that the laser beam is imaged by means of an imaging optics in a plane in which the beam properties (parameters) of the imaged laser beam are set, and that the beam from this plane is projected onto the one to be ablated by means of further imaging optics Surface is mapped. In this plane, which can also be referred to as a "fictitious mask plane", the parameters of the laser beam, namely in particular its dimensions in the direction of the long and short axes and its homogeneity, can be set independently of one another for both axis directions and the beam is then included mapped these set parameters on the working level (i.e. the surface to be removed). There is no need to arrange a mask in the "fictitious mask plane". A mask is placed directly in front of the eye and the radiation spot is guided over the mask by means of a scanner, as described in DE 42 32 690 C1. The dimensions of the mask can be changed in order to effect a certain ablation on the cornea of the eye. The scanner moves the radiation spot in the direction of the short cross-sectional axis over the opening of the mask arranged in front of the eye.
In Abwandlung des vorstehend beschriebenen Ausführungsbei- spiels kann eine Maske, statt vor dem Auge, in der "fiktiven Maskenebene" angeordnet werden. Die Öffnung dieser Maske wird dann mit dem Laserstrahl homogen ausgeleuchtet, d.h. die Maske wird so in den Strahlengang gestellt, daß ein besonders homo¬ gener Bereich des Laserstrahls durchgelassen wird. Der bei diesem Ausführungsbeispiel zwischen Maske und Auge angeordnete Scanner bewegt dann den Strahlungsfleck über die abzutragende Hornhaut.In a modification of the exemplary embodiment described above, a mask can be arranged in the "fictitious mask plane" instead of in front of the eye. The opening of this mask will then homogeneously illuminated with the laser beam, ie the mask is placed in the beam path in such a way that a particularly homogeneous area of the laser beam is let through. The scanner arranged between mask and eye in this exemplary embodiment then moves the radiation spot over the cornea to be removed.
Bevorzugt wird der Strahlungsfleck auf der Hornhaut auf Ab¬ messungen von 1 bis 2 mm reduziert (durch Zusammenwirken der Maske und der optischen Abbildungsmittel) .The radiation spot on the cornea is preferably reduced to dimensions of 1 to 2 mm (by interaction of the mask and the optical imaging means).
Unabhängig von der Justierung des Laserresonators kann mit der Erfindung erreicht werden, daß der Strahl in der Ebene der abzutragenden Oberfläche immer die gleichen Strahlparameter (insbesondere seine Abmessungen und seine Homogenität) auf¬ weist.Regardless of the adjustment of the laser resonator, it can be achieved with the invention that the beam always has the same beam parameters (in particular its dimensions and its homogeneity) in the plane of the surface to be removed.
Mit einer erfindungsgemäßen Vorrichtung bzw. dem Verfahren wird erreicht, daß die Homogenisieroptik die Parameter des Laserstrahls in der Ebene der abzutragenden Oberfläche weit¬ gehend unabhängig macht von der Qualität des vom Laser emit¬ tierten Strahls. Auch kann die gesamte vom Laser abgestrahlte Energie auf der zu bearbeitenden Oberfläche gebündelt werden.With a device or the method according to the invention it is achieved that the homogenizing optics make the parameters of the laser beam in the plane of the surface to be removed largely independent of the quality of the beam emitted by the laser. The entire energy emitted by the laser can also be concentrated on the surface to be processed.
Mit der Vorrichtung und dem Verfahren wird erreicht, daß ins¬ gesamt die vom Objekt pro Flächeneinheit empfangene Strahlen¬ intensität bis auf Schwankungen von höchstens 10% (in beiden Richtungen) homogen ist.It is achieved with the device and the method that the radiation intensity received by the object per unit area is homogeneous apart from fluctuations of at most 10% (in both directions).
Die Erfindung erlaubt es auch, in einfacher Weise mittels Abschwächern die Energie der Laserpulse in der gewünschten Weise einzustellen, ohne daß dabei die Abmessungen des Strahls beeinflußt werden.The invention also allows the energy of the laser pulses to be set in the desired manner in a simple manner by means of attenuators, without the dimensions of the beam being influenced.
Nachfolgend wird ein Ausführungsbeispiel der Erfindung anhand der Zeichnung näher erläutert. Fig. 1 zeigt schematisch eine Abbildungsoptik, die in Richtung der kurzen Querschnittsachse eines Excimerlaserstrahls wirksam ist undAn exemplary embodiment of the invention is explained in more detail below with reference to the drawing. 1 schematically shows an imaging optical system which is effective in the direction of the short cross-sectional axis of an excimer laser beam and
Fig. 2 zeigt eine Abbildungs- und Homogenisieroptik, die in Richtung der langen Achse desselben Excimerlaserstrahls wirksam ist.Fig. 2 shows an imaging and homogenizing optics, which is effective in the direction of the long axis of the same excimer laser beam.
Die Figuren 1 und 2 zeigen dieselbe Abbildungs- und Homogeni¬ sieroptik in zwei Ansichten, die zueinander im rechten Winkel stehen.Figures 1 and 2 show the same imaging and homogenizing optics in two views that are at right angles to each other.
Wie oben bereits ausgeführt ist, bewirkt die Optik in Richtung der kurzen Achse keine Homogenisierung, vielmehr wird das Intensitätsprofil, wie es vom Laser (nicht gezeigt) abgegeben wird, beibehalten, also zum Beispiel ein Gaußprofil. In Rich¬ tung der langen Achse erfolgt hingegen eine Homogenisierung.As already explained above, the optics do not bring about homogenization in the direction of the short axis, rather the intensity profile as it is emitted by the laser (not shown) is retained, for example a Gaussian profile. In contrast, homogenization takes place in the direction of the long axis.
Der vom Excimerlaser emittierte Laserstrahl 10 tritt gemäß den Figuren 1 und 2 zunächst in eine Homogenisieroptik aus den Ele¬ menten 12 und 14 ein. Die Homogenisieroptik besteht auch zwei Reihen von Zylinderlinsen (vgl. Fig. 2) und ist als solche be¬ kannt (US-PS 5,414,559). Grundsätzlich können auch andere als solche bekannte Homogenisieroptiken verwendet werden, vgl. zum Beispiel DE-OS 42 20 705, DE 38 29 728 und DE 38 41 045.According to FIGS. 1 and 2, the laser beam 10 emitted by the excimer laser first enters a homogenizing optics from elements 12 and 14. The homogenizing optics also consist of two rows of cylindrical lenses (see FIG. 2) and are known as such (US Pat. No. 5,414,559). In principle, other homogenizing optics known as such can also be used, cf. for example DE-OS 42 20 705, DE 38 29 728 and DE 38 41 045.
Wie die schematische Darstellung in den Figuren 1 und 2 zeigt, sind die zwei parallelen Reihen 12, 14 von Zylinderlinsen so ausgerichtet, daß sie nur in Richtung der langen Achse eine Homogenisierung bewirken, während der Strahl in Richtung der kurzen Achse (Fig. l) keine Homogenisierung erfährt.As the schematic representation in FIGS. 1 and 2 shows, the two parallel rows 12, 14 of cylindrical lenses are oriented such that they bring about homogenization only in the direction of the long axis, while the beam in the direction of the short axis (FIG. 1) undergoes no homogenization.
Wie ein Vergleich der Figuren 1 und 2 ebenfalls ergibt, ist im Strahlengang hinter der Homogenisieroptik 12, 14 eine Sammel¬ linse 16 angeordnet, die nur in Richtung der langen Achse eine Sammelwirkung hat. Eine weitere Sammellinse 18 im Strahlengang hat nur in Bezug auf die kurze Achse eine Sammelwirkung. Eine im Strahlengang dahinter angeordnete Sammellinse 20 hingegen wirkt wiederum nur in Richtung der langen Achse.As a comparison of FIGS. 1 and 2 also shows, a collecting lens 16 is arranged in the beam path behind the homogenizing optics 12, 14, which has a collecting effect only in the direction of the long axis. Another converging lens 18 in the beam path only has a collective effect with regard to the short axis. A converging lens 20 arranged behind it in the beam path, on the other hand, only acts in the direction of the long axis.
Die genannten optischen Elemente mit den Bezugszeichen 12, 14 und 16 bilden insgesamt eine Homogenisieroptik bezüglich der langen Achse des Laserstrahlprofils.The above-mentioned optical elements with the reference numerals 12, 14 and 16 form an overall homogenizing optical system with respect to the long axis of the laser beam profile.
Die Sammellinse 18 wirkt nur in Bezug auf die kurze Achse, ist also als Zylinderlinse (Zylinderform senkrecht zur Zeichnungs¬ ebene) ausgebildet und dient zur Einstellung der Strahlabmes¬ sung in Richtung der kurzen Achse, wobei das gaußähnliche Strahlprofil erhalten bleibt.The converging lens 18 acts only with respect to the short axis, that is to say it is designed as a cylindrical lens (cylinder shape perpendicular to the plane of the drawing) and is used to adjust the beam dimension in the direction of the short axis, the Gaussian-like beam profile being retained.
Die bezüglich der langen Achse bündelnde Sammellinse 20 ist ebenfalls als Zylinderlinse ausgebildet. Der Abtaster 26 ist insbesondere in Richtung der kurzen Achse bewegbar, so daß keine weitere Homogenisieroptik, die in Richtung dieser Achse wirksam wäre, erforderlich ist. Der Strahl wird überlappend sukzessive über die zu bearbeitende Oberfläche 30 bewegt, wobei die Überlappung so gewählt wird, daß auch in dieser Richtung eine weitgehende Homogenisierung der Intensität mit Intensi¬ tätsschwankungen kleiner als 10% gegeben ist.The converging lens 20 focusing with respect to the long axis is also designed as a cylindrical lens. The scanner 26 can be moved in particular in the direction of the short axis, so that no further homogenizing optics which would be effective in the direction of this axis are required. The beam is successively moved overlapping over the surface 30 to be machined, the overlap being selected such that there is also extensive homogenization of the intensity in this direction with intensity fluctuations of less than 10%.
Mit dem Bezugszeichen 22 ist in den Figuren 1 und 2 eine Ebene gekennzeichnet, in der mittels der im Strahlengang davor ange¬ ordneten optischen Elemente die Parameter des Laserstrahls, nämlich insbesondere seine Abmessungen in beiden Achsrichtungen und seine Homogenität, eingestellt werden. Diese Einstellung ist mit den beschriebenen optischen Elementen in beiden Achs¬ richtungen unabhängig voneinander möglich, d.h. für ein gege¬ benes System können die optischen Elemente so ausgewählt werden, daß für beide Achsrichtungen gewünschte Strahlparameter in der Ebene 22 vorliegen. Diese Ebene 22 ist oben als "fiktive Maskenebene" bezeichnet.The reference numeral 22 in FIGS. 1 and 2 denotes a plane in which the parameters of the laser beam, namely in particular its dimensions in both axial directions and its homogeneity, are set by means of the optical elements arranged in front of it in the beam path. With the optical elements described, this setting is possible in both axial directions independently of one another, i.e. for a given system, the optical elements can be selected so that the desired beam parameters are present in the plane 22 for both axial directions. This level 22 is referred to above as the "fictitious mask level".
Die mit dem Bauelement 24 schematisch angedeutete sphärische Abbildungsoptik bildet den Strahl mit den genannten einge¬ stellten Parametern aus der Ebene 22 in die Ebene der zu bearbeitenden Oberfläche 30 ab. Dabei kann auf eine Maske verzichtet werden.The spherical schematically indicated with the component 24 Imaging optics images the beam with the parameters set from the plane 22 into the plane of the surface 30 to be processed. There is no need for a mask.
Mit dem Abtastkopf 26 (Scanner) wird der Strahl auf der abzu¬ tragenden Oberfläche 30 in der gewünschten Weise (siehe oben) bewegt.The scanning head 26 (scanner) moves the beam on the surface 30 to be removed in the desired manner (see above).
In Abwandlung des vorstehend beschriebenen Ausführungsbei¬ spiels kann in der Ebene 22 auch eine Maske angeordnet werden, deren Öffnung schematisch durch das Bezugszeichen 28 gekenn¬ zeichnet ist. Diese Maske kann einen bestimmten Abschnitt des Laserstrahls durchlassen, der zum Beispiel unter dem Gesichts¬ punkt optimaler Homogenität ausgewählt wird. Dann wird mit der beschriebenen Optik der Öffnungsbereich der Maske auf die zu bearbeitende Oberfläche 30 abgebildet. In a modification of the exemplary embodiment described above, a mask can also be arranged in the plane 22, the opening of which is schematically identified by the reference numeral 28. This mask can let through a certain section of the laser beam, which is selected, for example, from the point of view of optimal homogeneity. Then the opening area of the mask is imaged on the surface 30 to be processed with the described optics.

Claims

Patentansprüche claims
1. Verfahren zum Abtragen von Material von der Oberfläche (30) eines Objektes, insbesondere zum ophthalmologischen For¬ men von Linsen, mittels eines auf das Objekt gerichteten gepulsten Laserstrahles (10), der einen Querschnitt mit einer längeren Achse und einer kürzeren Achse hat und dessen Inten¬ sitätsprofil in Richtung der langen Achse verschieden ist von seinem zumindest annähernd gaußförmigen Intensitätsprofil in Richtung der kurzen Achse, und dessen Querschnitt deutlich kleiner ist als die abzutragende Oberfläche, wobei der Laserstrahl in Richtung der kurzen Querschnittsachse unter Beibehaltung des gaußförmigen Intensitätsprofils so sukzessive über die abzutragende Oberfläche (30) geführt wird, daß auf¬ einanderfolgende Laserpulse einander überlappen und zueinander versetzt sind, dadurch gekennzeichnet, daß das Intensitätsprofil des Laserstrahls in Richtung der langen Querschnittsachse so homogenisiert wird, daß es möglichst annä¬ hernd Rechteckform mit Intensitätsschwankungen kleiner als ±5% hat.1. A method for removing material from the surface (30) of an object, in particular for ophthalmological shaping of lenses, by means of a pulsed laser beam (10) directed onto the object, which has a cross section with a longer axis and a shorter axis, and whose intensity profile in the direction of the long axis is different from its at least approximately Gaussian intensity profile in the direction of the short axis, and whose cross-section is significantly smaller than the surface to be removed, the laser beam gradually moving in the direction of the short cross-sectional axis while maintaining the Gaussian intensity profile the surface (30) to be removed is guided such that successive laser pulses overlap and are offset from one another, characterized in that the intensity profile of the laser beam is homogenized in the direction of the long cross-sectional axis in such a way that it is approximately rectangular in shape t has fluctuations in intensity of less than ± 5%.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Abbildungsoptik und gegebenenfalls die Homogenisieroptik für die langen und kurzen Achsen des Laserstrahls anamorpho- tisch sind. 2. The method according to claim 1, characterized in that the imaging optics and optionally the homogenizing optics for the long and short axes of the laser beam are anamorphic.
3. Verfahren nach einem der Ansprüche 1 oder 2, dadurch gekennzeichnet, daß der Laserstrahl (10) mittels einer Abbildungsoptik (12, 14, 16, 18, 20) in eine Ebene (22) abgebildet wird, in der die Strahleigenschaften des abgebildeten Laserstrahls eingestellt werden, und daß der Strahl aus dieser Ebene (22) mittels einer weiteren Abbildungsoptik (24) auf die abzutragende Oberfläche (30) abgebildet wird.3. The method according to any one of claims 1 or 2, characterized in that the laser beam (10) by means of imaging optics (12, 14, 16, 18, 20) is imaged in a plane (22) in which the beam properties of the imaged laser beam can be set and that the beam from this plane (22) is imaged on the surface (30) to be ablated by means of a further imaging optics (24).
4. Verfahren nach einem der vorherigen Ansprüche, dadurch gekennzeichnet, daß der Laserstrahl mittels eines Abtasters (26) , der zwischen den Abbildungsoptiken (12 - 24) und der abzutragenden Oberfläche - (30) angeordnet ist, über die Oberfläche (30) geführt wird.4. The method according to any one of the preceding claims, characterized in that the laser beam is guided over the surface (30) by means of a scanner (26) which is arranged between the imaging optics (12 - 24) and the surface to be removed - (30) .
5. Vorrichtung zum Abtragen von Material von der Oberfläche (30) eines Objektes, insbesondere zum ophthalmologischen For¬ men von Linsen, mittels eines auf das Objekt gerichteten gepulsten Laserstrahles (10) , der einen Querschnitt mit einer längeren Achse und einer kürzeren Achse hat und dessen Inten¬ sitätsprofil in Richtung der langen Achse verschieden ist von seinem zumindest annähernd gaußförmigen Intensitätsprofil in Richtung der kurzen Achse, und dessen Querschnitt deutlich kleiner ist als die abzutragende Oberfläche, wobei der Laserstrahl in Richtung der kurzen Querschnittsachse unter Beibehaltung des gaußförmigen Intensitätsprofils so sukzessive über die abzutragende Oberfläche (30) geführt wird, daß auf¬ einanderfolgende Laserpulse einander überlappen und zueinander versetzt sind, dadurch gekennzeichnet, daß eine Homogenisieroptik (12, 14) das Intensitätsprofil des Laserstrahls in Richtung der langen Querschnittsachse so homogenisiert, daß es möglichst annähernd Rechteckform mit Intensitätsschwankungen kleiner als ±5% hat. 5. Device for removing material from the surface (30) of an object, in particular for ophthalmological shaping of lenses, by means of a pulsed laser beam (10) directed onto the object, which has a cross section with a longer axis and a shorter axis, and whose intensity profile in the direction of the long axis is different from its at least approximately Gaussian intensity profile in the direction of the short axis, and whose cross-section is significantly smaller than the surface to be removed, the laser beam gradually moving in the direction of the short cross-sectional axis while maintaining the Gaussian intensity profile the surface (30) to be removed is guided such that successive laser pulses overlap and are offset from one another, characterized in that homogenizing optics (12, 14) homogenize the intensity profile of the laser beam in the direction of the long cross-sectional axis so that it is as possible has an approximately rectangular shape with intensity fluctuations of less than ± 5%.
6. Vorrichtung nach Anspruch 5, dadurch gekennzeichnet, daß die Abbildungsoptiken (18 - 20) für die kurze Achse einerseits und die Homogenisieroptik (12, 14, 16) sowie die Abbildungs¬ optik (20) für die lange Achse des Laserstrahls andererseits anamorphotisch sind.6. The device according to claim 5, characterized in that the imaging optics (18 - 20) for the short axis on the one hand and the homogenizing optics (12, 14, 16) and the imaging optics (20) for the long axis of the laser beam are anamorphic on the other hand .
7. Vorrichtung nach einem der Ansprüche 5 oder 6, dadurch gekennzeichnet, daß ein den Laserstrahl in zumindest der Richtung der kurzen Quer¬ schnittsachse des Laserstrahls bewegender Abtaster (26) zwi¬ schen den Abbildungsoptiken (12 - 24) und der abzutragenden Oberfläche (30) angeordnet ist.7. Device according to one of claims 5 or 6, characterized in that a scanner (26) moving the laser beam in at least the direction of the short cross-sectional axis of the laser beam between the imaging optics (12 - 24) and the surface to be removed (30 ) is arranged.
8. Vorrichtung nach einem der Ansprüche 5 bis 7, dadurch gekennzeichnet, daß der Laserstrahl in eine Ebene (22) abgebildet wird und daß in dieser Ebene eine Öffnung (28) in einer Maske homogen ausge¬ leuchtet wird und daß die Öffnung (28) auf die zu bearbeitende Oberfläche (30) abgebildet und der abgebildete Strahlungsfleck mittels eines Abtasters (26) in Richtungen parallel zur Ober¬ fläche (30) bewegt wird. 8. Device according to one of claims 5 to 7, characterized in that the laser beam is imaged in a plane (22) and that in this plane an opening (28) is homogeneously illuminated in a mask and that the opening (28) mapped onto the surface to be processed (30) and the depicted radiation spot is moved in a direction parallel to the surface (30) by means of a scanner (26).
PCT/EP1997/002331 1996-05-14 1997-05-07 Process and device for removal of material with a laser beam WO1997043078A1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999020429A1 (en) * 1997-10-22 1999-04-29 Aesculap-Meditec Gmbh Object figuring device
US20170266946A1 (en) * 2009-12-07 2017-09-21 Ipg Photonics Corporation Laser lift off systems and methods that overlap irradiation zones to provide multiple pulses of laser irradiation per location at an interface between layers to be separated

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999039410A1 (en) * 1998-01-29 1999-08-05 Visx, Incorporated Laser delivery system and method with diffractive optic beam integration
DE19915000C2 (en) * 1999-04-01 2002-05-08 Microlas Lasersystem Gmbh Device and method for controlling the intensity distribution of a laser beam
US6497701B2 (en) * 1999-04-30 2002-12-24 Visx, Incorporated Method and system for ablating surfaces with partially overlapping craters having consistent curvature
TW482705B (en) * 1999-05-28 2002-04-11 Electro Scient Ind Inc Beam shaping and projection imaging with solid state UV Gaussian beam to form blind vias
US6791060B2 (en) 1999-05-28 2004-09-14 Electro Scientific Industries, Inc. Beam shaping and projection imaging with solid state UV gaussian beam to form vias
DE10327733C5 (en) * 2003-06-18 2012-04-19 Limo Patentverwaltung Gmbh & Co. Kg Device for shaping a light beam
DE102005013949A1 (en) 2005-03-26 2006-09-28 Carl Zeiss Meditec Ag scanning device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4911711A (en) * 1986-12-05 1990-03-27 Taunton Technologies, Inc. Sculpture apparatus for correcting curvature of the cornea
DE4141890A1 (en) * 1990-12-28 1992-07-02 Nidek Kk Eye cornea laser beam treating appts. - corrects for non-uniform gauss distribution of beam in Y-axis using microprocessor control
DE4232690C1 (en) * 1992-09-30 1994-04-07 Aesculap Ag Method and device for correcting the shape of a lens

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1208466A (en) * 1982-07-28 1986-07-29 Donald R. Scifres Beam collimation and focusing of multi-emitter or broad emitter lasers
US4733944A (en) * 1986-01-24 1988-03-29 Xmr, Inc. Optical beam integration system
DE4220705C2 (en) * 1992-06-24 2003-03-13 Lambda Physik Ag Device for splitting a light beam into homogeneous partial beams
JPH0727993A (en) * 1993-07-07 1995-01-31 Matsushita Electric Ind Co Ltd Optical system with uniformalized light beam

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4911711A (en) * 1986-12-05 1990-03-27 Taunton Technologies, Inc. Sculpture apparatus for correcting curvature of the cornea
DE4141890A1 (en) * 1990-12-28 1992-07-02 Nidek Kk Eye cornea laser beam treating appts. - corrects for non-uniform gauss distribution of beam in Y-axis using microprocessor control
DE4232690C1 (en) * 1992-09-30 1994-04-07 Aesculap Ag Method and device for correcting the shape of a lens

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999020429A1 (en) * 1997-10-22 1999-04-29 Aesculap-Meditec Gmbh Object figuring device
US7128737B1 (en) * 1997-10-22 2006-10-31 Carl Zeiss Meditec Ag Object figuring device
US7545515B2 (en) 1997-10-22 2009-06-09 Carl Zeiss Meditec Ag Object shaping device
US7859684B2 (en) 1997-10-22 2010-12-28 Carl Zeiss Meditec Ag Object figuring device
US20170266946A1 (en) * 2009-12-07 2017-09-21 Ipg Photonics Corporation Laser lift off systems and methods that overlap irradiation zones to provide multiple pulses of laser irradiation per location at an interface between layers to be separated
US10974494B2 (en) * 2009-12-07 2021-04-13 Ipg Photonics Corporation Laser lift off systems and methods that overlap irradiation zones to provide multiple pulses of laser irradiation per location at an interface between layers to be separated

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