572 results about "Wavefront aberration" patented technology

The present invention provides an ophthalmic lens capable of correcting or minimizing presbyopia, or of functioning used as an anti-myopic lens. The ophthalmic lens can be a contact lens, a phakic intraocular lens or an aphakic intraocular lens. The ophthalmic lens comprises an optical zone, the optical zone having a first surface and an opposite second surface and including a coma-like wavefront aberration oriented vertically from the top to the bottom of the ophthalmic lens. In addition, the present invention provides a method for minimizing/correcting presbyopia or for preventing children's eyes from becoming severely myopic.

A combination of a scanning laser ophthalmoscope and external laser sources (52) is used for microphotocoagulation and photodynamic therapy, two examples of selective therapeutic laser. A linkage device incorporating a beamsplitter (56) and collimator-telescope (60) is adjusted to align the pivot point (16) of the scanning lasers (38, 40) and external laser source (52). A similar pivot point minimizes wavefront aberrations, enables precise focusing and registration of the therapeutic laser beam (52) on the retina without the risk of vignetting. One confocal detection pathway of the scanning laser ophthalmoscope images the retina. A second and synchronized detection pathway with a different barrier filter (48) is needed to draw the position and extent of the therapeutic laser spot on the retinal image, as an overlay (64). Advanced spatial modulation increases the selectivity of the therapeutic laser. In microphotocoagulation, an adaptive optics lens (318) is attached to the scanning laser ophthalmoscope, in proximity of the eye. It corrects the higher order optical aberrations of the eye optics, resulting in smaller and better focused applications. In photodynamic therapy, a spatial modulator (420) is placed within the collimator-telescope (60) of the therapeutic laser beam (52), customizing its shape as needed. A similar effect can be obtained by modulating a scanning laser source (38) of appropriate wavelength for photodynamic therapy.

In one embodiment, an apparatus for optimizing vision correction procedures comprising: a narrow beam of light directed to a patient's retina; a dynamic defocus and compensation offsetting device configured to offset the defocus of a wavefront from an eye, a wavefront sensor configured to measure the local tilt of a number of subwavefronts sampled around an annular ring (the diameter of which can be dynamically changed) over the wavefront with the defocus offset; and a display device configured to display a two dimensional (2D) data points pattern in real time with each data point location representing a corresponding local tilt of the sampled subwavefronts. A proper defocus offset, not passive compensation, can reveal the predominant feature(s) of other wavefront aberration component(s), thus enabling a refractive surgeon to fine tune the vision correction procedure and minimize the remaining wavefront aberration(s) in real time. Meanwhile, by sampling the wavefront around annular rings and displaying the local tilt of the sampled subwavefronts on a monitor in the form of a 2D data points pattern, a refractive ophthalmic surgeon can easily correlate the measurement result to the two major refractive errors, namely spherical and cylinder refractive errors, including the axis of astigmatism.

A system and method for specifying a vision correction prescription for a patient's eye, wherein in one embodiment, the method includes obtaining a wavefront aberration measurement of the patient's eye, applying at least one value from the wavefront aberration measurement to a statistical model trained using a plurality of objectively measured aberration values and a plurality subjectively measured visual acuity values as training data; and predicting a vision correction prescription for the patient's eye based on the at least one value and the statistical model.

A combination of a confocal scanning laser ophthalmoscope and external laser sources is used for microphotocoagulation purposes. An opto-mechanical linkage device and beamsplitter is used to align the pivot point of the Maxwellian view of the scanning laser ophthalmoscope with the pivot point of non-scanning external laser beams. The same pivot point is necessary to minimize wavefront aberrations and to enable precise focussing of a therapeutic laser beam on the retina. An AOM and/or two-dimensional AOD can be inserted in the pathway of the Gaussian therapeutic beam to control intensity and spatial pattern of small and short-duration pulses. The location of the external laser beam on the retina is determined with the help of two synchronized detectors and image processing. One detector is used to localize moving fiducial landmarks of the retina. A second detector is used to locate on the retina the external laser aiming beam. Two different confocal apertures are used. Polarizing the aiming beam is necessary to further reduce unwanted reflections from the anterior corneal surface.

A method for at least one of preventing myopia and retarding the progression of myopia is provided. The method includes measuring optical aberrations in a human eye and correcting the optical aberrations. Measuring optical aberrations may include measuring wavefront aberrations of parallel light rays entering the eye.

A method of correcting wavefront aberrations of an eye includes determining a high precision conventional intrastromal corneal ablation profile based on a direct removal of the intrastromal corneal tissue. An expanded ablation volume profile is constructed based on the direct tissue removal profile and the expanded tissue volume is to be ablated instead to correct to the wavefront aberrations. The thickness of the ablated profile of a conventional ablation profile is expanded by an expansion factor (Nc-1)/(Nm-Nc), Nc is the index of refraction of the cornea and Nm the index of fill material. An expanded ablation volume filled with the fill material produces the effect of correcting wavefront aberrations as if a much smaller tissue volume were ablated without the fill material.

A method of measuring eye refraction to achieve desired quality according to a selected vision characteristics comprising the steps of selecting a characteristic of vision to correlate to the desired quality of vision from a group of vision characteristics comprising acuity, Strehl ratio, contrast sensitivity, night vision, day vision, and depth of focus, dynamic refraction over a period of time during focus accommodation, and dynamic refraction over a period of time during pupil constriction and dilation; using wavefront aberration measurements to objectively measure the state of the eye refraction that defines the desired vision characteristic; and expressing the measured state of refraction with a mathematical function to enable correction of the pre-selected vision characteristic to achieve the desired quality of vision. The mathematical function of expression may be a Zernike polynomial having both second order and higher order terms or a function determined by spline mathematical calculations. The pre-selected desired vision characteristics may be determined using ray tracing technology.

Devices and methods for controlling myopia are provided. The devices and methods relate to the inventors discovery of the relationship between near work, the forces applied to the eye by the eyelids and myopia. The devices include a contact lens comprising a region that disperses force applied to the eye by an eyelid. The devices also include a device designed by measuring first wavefront aberrations of an eye before pre-near work and measuring second measured wavefront aberrations of the eye post-near work. The methods include a method for controlling myopia including identifying optical changes associated with near work and correcting the optical changes with an optical device.

A beam control system and method: The inventive system includes, an arrangement for receiving a first beam of electromagnetic energy; measuring wavefront aberrations in the first beam with a wavefront sensor; and removing global tilt from the measured wavefront aberrations to provide higher order aberrations for beam control. In the illustrative embodiment, the invention uses a traditional (quad-cell) Shack-Hartmann wavefront sensor to measure wavefront aberrations. An adaptive optics processor electronically removes the global tilt (angular jitter) from this measurement leaving only the higher-order Zernike components. These higher-order aberrations are then applied to wavefront control elements, such as deformable mirrors or spatial light modulators that correct the tracker image and apply a conjugate distortion to the wavefront of the outgoing HEL beam. A track error (angular jitter) component is supplied by a separate fine track sensor. This jitter error is then applied by the adaptive optics processor to a fast steering mirror, which corrects jitter in the tracker image and applies a compensating distortion to the LOS of the HEL beam.

A vision metric, called the sharpness metric, indicates the subjective sharpness of a patient's vision by taking into account both the wavefront aberration and the retinal response to the image. A retinal image quality function such as the point spread function is convolved by a neural quality function, and the maximum of the convolution over the retinal plane provides the sharpness metric. The sharpness metric can be used to control eye surgery or the fabrication of a lens.

Contact lenses, such as prism ballasted toric lenses, having anterior and posterior surfaces related by way of non-axisymmetric thickness variation can exhibit a third-order aberration, particularly vertical coma. A wavefront modifier, such as an aspheric surface modification, is incorporated into the lenses to at least partially compensate for the wavefront aberration associated with the non-axisymmetric thickness variation. A magnitude of the modifications can be adjusted to set a target value for any remaining wavefront aberration of the lenses based on a population-wide goal.

A second communications server obtains adjustment information of an adjustment unit in an exposure apparatus and information related to image forming quality (such as wavefront aberration) of a projection optical system under an exposure condition that serves as a reference, via a first communications server, and then calculates an optimal adjustment amount of the adjustment unit under a target exposure condition based on the information. In addition, the second communications server obtains adjustment information of the adjustment and actual measurement data of image forming quality of the projection optical system via the first communications server, and then calculates the optimal adjustment amount of the adjustment unit under the target exposure condition based on the information. And, the second communications server controls the adjustment unit in the exposure apparatus via the first communications server, based on the calculations results.

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.

An improved moiré deflectometer device for measuring a wavefront aberration of an optical system includes a light source for illuminating a surface area of the optical system, an optical relay system for directing scattered light to a deflectometer component that converts the wavefront into a moiré fringe pattern, a sensor/camera assembly for imaging and displaying the exit pupil of the optical system and the moire fringe pattern, and a fringe pattern to calculate the wavefront aberration of the optical system, being improved by an illumination source for illuminating the exit pupil of the optical system; and an alignment system cooperating with the illumination source in such a manner to consistently and accurately align a measurement axis of the device to the optical system. An associated method is also disclosed.