Patents by Inventor Gerhard Youssefi

Gerhard Youssefi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8186830
    Abstract: An improved aberrometer is disclosed having a variable visible illumination fixation target for controlling pupil size for the diagnostic images.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: May 29, 2012
    Assignee: Bausch & Lomb Incorporated
    Inventors: Ulf Grotehusmann, Gerhard Youssefi
  • Publication number: 20110276043
    Abstract: The invention relates to an apparatus, an algorithm and a method for providing a laser shot file for use in a laser. The laser may be an excimer laser. The shot file may be applied for performing a refractive laser treatment of an eye or for producing a customized contact lens or an intraocular lens. According to the invention information with respect to a desired ablation profile is provided and a first series of laser shot positions is calculated based on the desired ablation profile. A simulated ablation profile is generated using said first series of laser shot positions and using information about pulse characteristics of a single laser shot. The simulated ablation profile is compared with the desired ablation profile and residual structures are determined.
    Type: Application
    Filed: April 29, 2011
    Publication date: November 10, 2011
    Inventors: Gerhard Youssefi, Ernst Hegels
  • Publication number: 20110208172
    Abstract: A refractive surgical system, comprising a refractive treatment apparatus adapted to alter multiple localized regions of a cornea and an ophthalmic measurement device adapted to measure a corneal shape parameter at at least two locations on the cornea. A corneal modeling apparatus and method to calculate anticipated corneal shape parameters at two or more locations based on parameters of a refractive treatment, and compare shape parameters measured at two or more locations on the cornea corresponding to the two or more locations of the anticipated corneal shape parameters.
    Type: Application
    Filed: February 25, 2011
    Publication date: August 25, 2011
    Inventors: Gerhard Youssefi, Julia Hoff, Birgit Lutzenberger, Anton Hilger
  • Publication number: 20110202045
    Abstract: The invention relates to an apparatus and a method for providing data for vision correction utilizing a volumetric ablation and an intrastromal manipulation. The provided data may be used by a laser ablating the surface of the cornea in combination with a laser which operates intrastromal to optimize a corneal re-shaping procedure. One aspects of the invention relates to the minimization of the amount of corneal tissue to be removed.
    Type: Application
    Filed: January 28, 2011
    Publication date: August 18, 2011
    Inventor: Gerhard Youssefi
  • Publication number: 20110137300
    Abstract: The invention relates to an apparatus and a method for determining the applicability of a treatment pattern for manipulation of a cornea of an eye using a laser. The concept of the present invention is based on the determination of an actual volumetric profile based on a set of input data and a theoretical volumetric profile which is created independently based on only the basic optical parameters. On the basis of a comparison of the determined volumetric profiles it is determined whether the actual volumetric profile is within predetermined tolerances.
    Type: Application
    Filed: December 7, 2010
    Publication date: June 9, 2011
    Inventors: Gerhard Youssefi, Anton Hilger
  • Patent number: 7895011
    Abstract: A method and apparatus for remotely verifying the calibration status of a diagnostic instrument, for example, following remote installation of a software upgrade on the instrument. In one example, a method of verifying the calibration status of the instrument, includes retrieving stored raw calibration test data generated during a previously-performed calibration of the instrument, processing the raw calibration test data to generate a diagnostic reading, comparing the diagnostic reading to a known nominal reading, and based on the comparison, generating an output indicative of the calibration status of the instrument. In one example, the method is performed without contemporaneously measuring a calibration object with the instrument and therefore, without activating the measurement head or measurement optics of the instrument.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: February 22, 2011
    Assignee: Bausch & Lomb Incorporated
    Inventors: Gerhard Youssefi, Julia Hoff, Anton Hilger, Michael L. Kliewer
  • Publication number: 20110007945
    Abstract: The invention is generally directed to the field of image processing, and more particularly to a method and an apparatus for determining a wavefront of an object, in particular a human eye. The invention discloses a method and an apparatus for real-time wavefront sensing of an optical system utilizing two different algorithms for detecting centroids of a centroid image as provided by a Hartmann-Shack wavefront sensor. A first algorithm detects an initial position of all centroids and a second algorithm detects incremental changes of all centroids detected by said first algorithm.
    Type: Application
    Filed: March 13, 2009
    Publication date: January 13, 2011
    Inventors: Gerhard Youssefi, Hans-Joachim Polland
  • Publication number: 20110002514
    Abstract: The invention relates to an apparatus and a method for determining the energy of a laser. In particular, the invention relates to an initial determination of a laser energy and the monitoring of the laser energy preferably of an excimer laser for use in a refractive laser system for treatment of any eye. An apparatus for determining an energy of an excimer laser comprises a tool comprising an area being ablated with a plurality of laser pulses of said excimer laser using at least one predetermined multi spot ablation pattern, said ablation area comprising a specific ablation area being as large as the ablation area or smaller, an image capturing means for capturing at least one image comprising at least said specific ablation area of the tool; an analyzing means for analyzing said at least one image, wherein the size of the specific ablation area provides a measure of the energy of the excimer laser.
    Type: Application
    Filed: December 12, 2008
    Publication date: January 6, 2011
    Applicant: TECHNOLAS PERFECT VISION GMBH
    Inventors: Gerhard Youssefi, Birgit Lutzenberger, Julia Hoff, Ernst Hegels
  • Patent number: 7771053
    Abstract: A selectively marked contact lens having, in one aspect, marks in an optical zone region on a surface thereof and, in another aspect, different marks outside an optical zone region of the lens, for an in-vivo lens. With the lens in-vivo, the subject's eye is illuminated and the lens is imaged. A fast algorithm is used to determine the mark coordinates in relation to a measured pupil coordinate to determine position and/or orientation of the contact lens. A wavefront aberration measurement can also be obtained simultaneously with the contact lens position measurement, as well as pupil size. A fast algorithm provides for online measurements; i.e., at a repetition rate of 10 Hz or greater, over a selected time interval. Blinking periods are determined and anomalous lens position and/or wavefront information is discarded. A most frequently occurring wavefront and/or contact lens position/orientation is determined over the selected time interval.
    Type: Grant
    Filed: July 22, 2004
    Date of Patent: August 10, 2010
    Assignee: Bausch & Lomb Incorporated
    Inventors: Hans-Joachim Polland, Stefan Seitz, Kristian Hohla, Gerhard Youssefi, Ernst Hegels, Birte Jansen, Christoph Sappel
  • Publication number: 20100153047
    Abstract: A method and apparatus for remotely verifying the calibration status of a diagnostic instrument, for example, following remote installation of a software upgrade on the instrument. In one example, a method of verifying the calibration status of the instrument, includes retrieving stored raw calibration test data generated during a previously-performed calibration of the instrument, processing the raw calibration test data to generate a diagnostic reading, comparing the diagnostic reading to a known nominal reading, and based on the comparison, generating an output indicative of the calibration status of the instrument. In one example, the method is performed without contemporaneously measuring a calibration object with the instrument and therefore, without activating the measurement head or measurement optics of the instrument.
    Type: Application
    Filed: December 17, 2008
    Publication date: June 17, 2010
    Inventors: Gerhard Youssefi, Julia Hoff, Anton Hilger, Michael L. Kliewer
  • Patent number: 7708411
    Abstract: A fast algorithm is presented which allows for substantially simultaneous acquisition, analysis, and display of a wavefront centroid image, referred to as online aberrometry. A method embodiment involves determination of an average, or most frequently occurring, wavefront aberration over a selected time interval, e.g., 20 sec. Online pupil diameter measurement allows analysis of wavefront aberration as a function of changing pupil size. A wavefront measuring apparatus is disclosed that supports online aberrometry.
    Type: Grant
    Filed: July 22, 2004
    Date of Patent: May 4, 2010
    Assignee: Bausch & Lomb Incorporated
    Inventors: Hans-Joachim Polland, Gerhard Youssefi, Stefan Seitz
  • Patent number: 7699837
    Abstract: Methods and apparatus for improving vision incorporate the effects of biodynamical and biomechanical (biological) responses of the eye. The eye produces a biological response to trauma, such as a LASIK keratectomy or other necessary traumatic procedure in preparation for refractive surgery. By observing the biological response, a prospective treatment to correct higher order aberrations is adjusted to compensate for the biological effects. An improved photorefractive surgery system incorporates one or more suitable diagnostic devices that provide biological response information in such a manner that the patient need not change position from that assumed for the surgical procedure.
    Type: Grant
    Filed: June 22, 2005
    Date of Patent: April 20, 2010
    Assignee: Technolas GmbH Ophthalmologishe Systeme
    Inventors: Ian G. Cox, Timothy N. Turner, Gerhard Youssefi
  • Patent number: 7654674
    Abstract: The invention relates to a method for determining the visual acuity of an eye and a respective apparatus. The method comprises the steps of: providing the wavefront information of the eye, generating a point spread function based on the wavefront information of the eye, said point spread function representing a specific intensity distribution for a corresponding pupil size. After comparing the intensities of the point spread function with a selectable intensity level of intensity, those parts of the point spread function having an intensity being larger than the selectable intensity level are determined as a relevant part of the point spread function.
    Type: Grant
    Filed: November 8, 2006
    Date of Patent: February 2, 2010
    Assignee: Bausch & Lomb Incorporated
    Inventors: Ernst Hegels, Gerhard Youssefi
  • Patent number: 7625089
    Abstract: An improved wavefront sensor is provided that enhances the initial focus and precision of imaged spots used to determine the monochromatic wave aberrations of the eye. The wavefront sensor includes an adjustment camera that is independent of a lenslet camera. A laser in a lower power mode is projected onto the retina of the eye and is brought into more precise or sharp focus by a control system employing data from the adjustment camera, which aids in focusing the imaged spots. “Trombone”-type optics are used to adjust the focus of the light projected onto the retina and the imaged spots onto a sensor. The laser has a higher power mode used when acquiring data of the imaged spots from the sensor.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: December 1, 2009
    Assignee: Bausch & Lomb Incorporated
    Inventors: Gerhard Youssefi, Hans-Joachim Polland, Christoph Sappel
  • Publication number: 20090161067
    Abstract: An ophthalmic instrument for use with a subject's eye, comprising an interferometer having a test arm in which the subject's eye is to be positioned and a reference arm, the reference arm including a mirror adapted to be positioned such that the reference arm has a predetermined length, and an ophthalmic apparatus coupled to the interferometer such that, by altering a test arm length, a length between the ophthalmic apparatus and the eye is also altered. The mirror is positioned to achieve the predetermined length and a length of the test arm is adjusted such that interference between the light reflected from the eye and the light reflected from the mirror is achieved, the ophthalmic apparatus is optically aligned with the eye.
    Type: Application
    Filed: December 15, 2008
    Publication date: June 25, 2009
    Inventors: Gerhard Youssefi, Rupert Veith
  • Publication number: 20090006508
    Abstract: A method and an apparatus for extrapolating diagnostic data relating to one pupil diameter to another pupil diameter. Embodiments according to the invention are more particularly directed to extrapolating wavefront aberration data, for example, in the form of Zernike polynomial data, obtained from a smaller pupil diameter, d1, to a larger pupil diameter, d2. Data relating to the first pupil diameter d1 may be obtained in a diagnostic procedure. In the extrapolation, a conversion matrix M is utilized. The conversion matrix M can be generated from a static matrix and a dynamic matrix, the latter taking the pupil diameter d1 into consideration. Data relating the first pupil diameter d1 and wavefront aberration data can be ordered via a permutation matrix P. If necessary, Extrapolated data can be re-ordered via a transposed permutation matrix PT.
    Type: Application
    Filed: June 27, 2007
    Publication date: January 1, 2009
    Inventors: Gerhard Youssefi, Anton Hilger, Julia Hoff
  • Publication number: 20080249514
    Abstract: A technique of refractive eye correction employs multiple steps to correct refractive errors in the eye. In the first step, gross decentrations of the refractive error are corrected, allowing the subsequent steps to be relatively symmetric in their treatment profile. Then, the eye's refractive error is again measured, and a subsequent treatment is applied for the remaining error. The overall treatment is thus completed in two or more steps.
    Type: Application
    Filed: April 25, 2008
    Publication date: October 9, 2008
    Inventors: Kristian Hohla, Gerhard Youssefi
  • Publication number: 20080246916
    Abstract: The invention relates to a method for determining the visual acuity of an eye and a respective apparatus. The method comprises the steps of: providing the wavefront information of the eye, generating a point spread function based on the wavefront information of the eye, said point spread function representing a specific intensity distribution for a corresponding pupil size. After comparing the intensities of the point spread function with a selectable intensity level of intensity, those parts of the point spread function having an intensity being larger than the selectable intensity level are determined as a relevant part of the point spread function.
    Type: Application
    Filed: November 8, 2006
    Publication date: October 9, 2008
    Inventors: Ernst Hegels, Gerhard Youssefi
  • Publication number: 20080228177
    Abstract: The present invention relates to a system and a method for calculating a course of refractive treatment for correcting a refractive error of a patient's eye. It is based on the concept to combine at least a first treatment which provides an overcorrection of the intended correction with at least a second treatment which corrects said overcorrection.
    Type: Application
    Filed: October 12, 2006
    Publication date: September 18, 2008
    Inventors: Friedrich Moritz, Gerhard Youssefi
  • Patent number: 7331667
    Abstract: Apparatus and methods are described for aligning diagnostic and therapeutic iris images, via iris pattern recognition, for effecting more accurate laser treatment of the eye. A method for aligning a dilated pupil diagnostic iris image associated with a diagnostic measurement for calculating a laser treatment, with a constricted pupil diagnostic iris image, by identifying an iris landmark that is not identifiable solely between the two images, includes a sequential plurality of diagnostic iris images of varying pupil size such that the iris landmark can be tracked between the two images. The aligned, constricted pupil diagnostic image can then be aligned with a constricted pupil treatment image and the ablation pattern rotated accordingly. Limbal edge detection is used in the diagnostic images to provide pupil center translation information for translational alignment of the laser treatment.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: February 19, 2008
    Assignee: Bausch Lomb Incorporated
    Inventors: Ulf Grotehusmann, Gerhard Youssefi