1134results about "Refractometers" patented technology

Methods and devices are described that are needed to design and fabricate modified surfaces on contact lenses or on corneal tissue that correct the eye's optical aberrations beyond defocus and astigmatism. The invention provides the means for: 1) measuring the eye's optical aberrations either with or without a contact lens in place on the cornea, 2) performing a mathematical analysis on the eye's optical aberrations in order to design a modified surface shape for the original contact lens or cornea that will correct the optical aberrations, 3) fabricating the aberration-correcting surface on a contact lens by diamond point turning, three dimensional contour cutting, laser ablation, thermal molding, photolithography, thin film deposition, or surface chemistry alteration, and 4) fabricating the aberration-correcting surface on a cornea by laser ablation.

A method for enhancing vision of an eye includes a laser delivery system having a laser beam for ablating corneal material from the cornea of the eye. Measurements are made to determine an optical path difference between a plane wave and a wavefront emanating from the retina of the eye for a location at a surface of the cornea. An optical correction is provided to the laser delivery system for the location based on the optical path difference and refractive indices of media through which the wavefront passes. The optical correction includes dividing the optical path difference by a difference between an index of refraction of corneal material and an index of refraction of air. The laser beam is directed to the location on the surface of the cornea and corneal material ablated at the location in response to the optical correction to cause the wavefront to approximate the shape of the plane wave at that location.

A refraction measuring instrument for measuring the refraction of an eye to be examined while the subject is viewing an external object in a more natural posture. A measuring light beam from a light source 21 is reflected from a mirror 25, shaped into a beam with a ring cross section, directed to a free curved surface prism 31 along an optical axis O2, reflected from a surface 31b and a beam splitting surface 31a, guided to an eye E along an optical axis O1 together with the visible light from outside the instrument, and form a ring pattern on the fundus F. The measurement beam reflected from the fundus F is received by a CCD 23 through the free curved surface prism 31 and a prism 22, and a ring pattern is imaged. A calculation control device 4 analyzes the imaged ring pattern and calculates the sphericity, the degree of astigmatism, and the astigmatic axis angle. For measurement, the subject A wears the refraction measuring instrument 1 on the head H through a wearing section 1a.

A system provides an optical image of an object. A first module tracks a reference feature of the object. A second module includes a source for an imaging beam, a scanning device to move the imaging beam along a portion of the object and a detection device receives a signal associated with an image of the portion of the object. The first module controls the position of the imaging beam relative to the reference feature to correct for the motion of the object. A third module detects a distortion of the object and compensates for the distortion.

Wavefront measuring systems and methods are disclosed which may be employed, for example, in detecting phase aberrations in a spectacle lens and in an eye. Various embodiments include disposing a modulation pattern in the path of a return beam from the spectacle lens or the eye, and imaging a diffraction pattern at a self-imaging plane relative to the modulation pattern with a detector. The diffraction pattern is analyzed and the results are used to produce a representation of the wavefront phase characteristics that describe aberrations in the lens or eye being measured. Illumination and processing techniques for improving the measurement results are dislcosed. Various embodiments comprise systems adaptable to both measure aberrations in lenses in spectacles as well as in a patient's eyes.

Blood glucose concentrations are measured by non-invasive methods and apparatus using visual pigment bleaching in conjunction with psychophysical methodologies. Bleaching light of selected wavelengths is projected through the pupil of the eye of an observer onto the fundus to bleach visual pigments in the eye. The observer's psychophysical response to a visual stimulus is then measured to obtain information regarding the rate of regeneration of the visual pigments. From the rate of pigment regeneration, blood glucose concentrations are measured accurately. The psychophysical methodologies that may be used with the invention include visual acuity tests and color-matching tests.

An improved ophthalmic instrument for in-vivo examination of a human eye including a wavefront sensor that estimates aberrations in reflections of the light formed as an image on the retina of the human eye and a phase compensator that spatially modulates the phase of incident light to compensate for the aberrations estimated by the wavefront sensor Optical elements create an image of a fixation target at the phase compensator, which produces a compensated image of the fixation target that compensates for aberrations estimated by the wavefront sensor. The compensated image of the fixation target produced by the phase compensator is recreated at the human eye to thereby provide the human eye with a view of compensation of the aberrations the human eye as estimated by the wavefront sensor. The phase compensator preferably comprises a variable focus lens that compensates for focusing errors and a deformable mirror that compensates for higher order aberrations. The optical elements preferably comprise a plurality of beam splitters and a plurality of lens groups each functioning as an afocal telescope. In addition, instruments and systems are provided that exploit these capabilities to enable efficient prescription and / or dispensing of corrective optics (e.g., contact lens and glasses).

Devices, systems, and methods measure, diagnose, and / or treat one or both eyes of a patient. Adaptive optics systems (such as those having a deformable mirror) may be configured to an aspherical or multi-spherical presbyopia-mitigating prescriptive shape to allow objective and / or subjective measurements of a candidate prescription. A plurality of viewing distances allow subjective and / or objective evaluations of performance using a light spot or a test viewing image. Measurements of aberrations at selected viewing conditions (including distances and / or brightness) with correlating pupil sizes may also be provided.

A method for the simultaneous measurement of the anterior and posterior corneal surfaces, corneal thickness, and optical aberrations of the eye. The method employs direct measurements and ray tracing to provide a wide range of measurements for use by the ophthalmic community.

A method and instrument to irradiate a light adjustable lens, for example, inside a human eye, with an appropriate amount of radiation in an appropriate intensity pattern by first measuring aberrations in the optical system containing the lens; aligning a source of the modifying radiation so as to impinge the radiation onto the lens in a pattern that will null the aberrations. The quantity of the impinging radiation is controlled by controlling the intensity and duration of the irradiation. The pattern is controlled and monitored while the lens is irradiated.

An improved ophthalmic instrument including an integral wavefront sensor and display device, wherein the wavefront sensor measures phase aberrations in reflections directed thereto to characterize aberrations of the eye and is operably coupled to the display device, which displays a graphical representation of the aberrations of the eye. Such graphical representation may include: two dimensional contour maps that graphically depict contribution of pre-specified terms (such as spherical aberration, astigmatism and coma) for the aberrations of the eye, coefficients corresponding to such pre-specified terms that characterize the aberrations of the eye, or predefined two-dimensional icons that provide a general graphical depiction of such prespecified terms. Such graphical representations provide the practitioner with valuable information characterizing the high order optical errors of the eye (which is far beyond the diopter information typically provided by current ophthalmic instruments) for use in diagnosis and treatment of abnormalities and disease in the eye.

Example embodiments of a large dynamic range sequential wavefront sensor for vision correction or assessment procedures are disclosed. An example embodiment optically relays a wavefront from an eye pupil or corneal plane to a wavefront sampling plane in such a manner that somewhere in the relaying process, the wavefront beam from the eye within a large eye diopter range is made to reside within a desired physical dimension over a certain axial distance range in a wavefront image space and / or a Fourier transform space. As a result, a wavefront beam shifting device can be disposed there to fully intercept and hence shift the whole beam to transversely shift the relayed wavefront.

A system for mapping a three-dimensional structure includes a projecting optical system adapted to project light onto an object, a correction system adapted to compensate the light for at least one aberration in the object, an imaging system adapted to collect light scattered by the object and a wavefront sensor adapted to receive the light collected by the imaging system and to sense a wavefront of the received light. For highly aberrated structures, a number of wavefront measurements are made which are valid over different portions of the structure, and the valid wavefront data is stitched together to yield a characterization of the total structure.

An apparatus for measuring optical aberrations of the human eye wherein the person positions his or her eye on an optical axis of the apparatus and looks at an illuminated target on the optical axis that is visible to the eye for allowing the eye to focus on the target and establish a position of the eye. A collimating lens on the optical axis is movable along the optical axis for adjusting the apparent optical distance between the eye and the target. A light source directs a predetermined light beam along the optical axis into the eye and onto the retina of the eye as a spot of light. A lens reimages the light scattered from the light spot on the eye retina into a wavefront curvature sensor that forms two oppositely defocused images on an image detector, and a computer processes and analyzes the two defocused images for measuring the optical aberrations of the eye.

A method and an instrument is provided for measuring aberration refraction of an eye with a first device for measuring the total aberration refraction of the eye and a second device for measuring the aberration refraction of the cornea of the eye. The component of aberration refraction caused by the lens caused by the lens is calculated using the measured total eye aberration refraction and the measured component of aberration refraction of the cornea mapped over the optical surfaces of the eye. Each component portion of the aberration refraction provides information usable for making appropriate corrective actions at the cornea, at the lens, or both as indicated by the mapped measurements and calculations.

An improved method for treating the eye includes the step of providing an ophthalmic instrument including an integral wavefront sensor. The wavefront sensor measures phase aberrations in reflections directed thereto to characterize aberrations of the eye. The wavefront sensor may be operably coupled to a display device, which displays a graphical representation of the aberrations of the eye. Such graphical representation may include: two dimensional contour maps that graphically depict contribution of pre-specified terms (such as spherical aberration, astigmatism and coma) for the aberrations of the eye, coefficients corresponding to such pre-specified terms that characterize the aberrations of the eye, or predefined two-dimensional icons that provide a general graphical depiction of such pre-specified terms. Such graphical representations provide the practitioner with valuable information characterizing the high order optical errors of the eye (which is far beyond the diopter information typically provided by current ophthalmic instruments) for use in diagnosis and treatment of abnormalities and disease in the eye. In addition, the wavefront sensor may be part of an adaptive optical subsystem that compensates for the phase aberrations measured therein to provide phase-aligned images of the eye for capture by an image capture subsystem. Such images may be used by practitioner in diagnosis and treatment of abnormalities and disease in the eye.

Methods, systems, and media relating the display of scattering and / or absorption characteristics of an optical medium. For scattering measurements, a Hartmann-Shack calibration image of a measurement system is acquired to define a first plurality of point spread functions. A Hartmann-Shack test image of the medium is acquired to define a second plurality of point spread functions. A shift is determined between the test image and the calibration image. A point spread of each of the second plurality of point spread functions is measured, each of the second plurality of point spread functions including a component due to optical aberration of the medium and a component due to scatter. The component due to optical aberration is determined using the shift. The component due to optical aberration is deconvolved to determine the component due to scatter. A display of the local scattering characteristics is generated using the component due to scatter. For absorption measurements, a plurality of spot intensity measurements are acquired of a medium, each spot intensity measurement including a component due to reflectivity and a component due to absorption. The component due to reflectivity is determined, and the component due to absorption is determined.

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.

The present invention provides a method for designing and making a customized ophthalmic lens, such as a contact lens or an intraocular lens, capable of correcting high-order aberrations of an eye. The posterior surface of the customized contact lens is designed to accommodate the corneal topography of an eye. The design of the customized ophthalmic lens is evaluated and optimized in an optimizing routine using a computational model eye that reproduces the aberrations and corneal topography of an eye. The present invention also provides a system and method for characterizing the optical metrology of a customized ophthalmic lens that is designed to correct aberrations of an eye. Furthermore, the present invention provides a business model and method for placing an order for a pair of customized ophthalmic lenses.

Augmented reality systems and methods for user health analysis. Methods for user health analysis may include collecting data for an initial prediction model and continuing to collect additional data based on one or more data criteria. The methods may further include updating the initial prediction model based on the additional data to produce a revised prediction model or causing an intervention to occur based on the additional data. The data may be collected by a display system including one or more sensors configured to collect user-specific data and a display device configured to present virtual content to a user. The display device may be configured to output light with variable wavefront divergence.

An apparatus for determining the refraction of a patient's eye includes a wavefront measurement device that determines aberrations in a return beam from the patient's eye viewing a target through a corrective test lens in the apparatus. The wavefront measurement device preferably outputs an display representative of the quality of vision afforded the patient through the test lens. The display may be, e.g., a representation of a Snellen chart convolved with the optical characteristics of the patient's vision, an overall quality of vision scale, or the optical contrast function, all of which are based on the wavefront measurements of the patient's eye. The examiner may use the display information to conduct a refraction examination or other vision tests without the subjective response from the patient.

Devices, systems, and methods for treating and / or determining appropriate prescriptions for one or both eyes of a patient are particularly well-suited for addressing presbyopia, often in combination with concurrent treatments of other vision defects. High-order spherical aberration may be imposed in one or both of a patient's eyes, often as a controlled amount of negative spherical aberration extending across a pupil. A desired presbyopia-mitigating quantity of high-order spherical aberration may be defined by one or more spherical Zernike coefficients, which may be combined with Zernike coefficients generated from a wavefront aberrometer. The resulting prescription can be imposed using refractive surgical techniques such as laser eye surgery, using intraocular lenses and other implanted structures, using contact lenses, using temporary or permanent corneal reshaping techniques, and / or the like.

A method and instrument to irradiate a light adjustable lens, for example, inside a human eye, with an appropriate amount of radiation in an appropriate intensity pattern by first measuring aberrations in the optical system containing the lens; aligning a source of the modifying radiation so as to impinge the radiation onto the lens in a pattern that will null the aberrations. The quantity of the impinging radiation is controlled by controlling the intensity and duration of the irradiation. The pattern is controlled and monitored while the lens is irradiated.

An ocular system for detecting ocular abnormalities and conditions creates photorefractive digital images of a patient's retinal reflex. The system includes a computer control system, a two-dimensional array of infrared irradiation sources and a digital infrared image sensor. The amount of light provided by the array of irradiation sources is adjusted by the computer so that ocular signals from the image sensor are within a targeted range. Enhanced, adaptive, photorefraction is used to observe and measure the optical effects of Keratoconus. Multiple near-infrared (NIR) sources are preferably used with the photorefractive configuration to quantitatively characterize the aberrations of the eye. The infrared light is invisible to a patient and makes the procedure more comfortable than current ocular examinations.

A modular fundus camera including an adaptive optical module that detachably interfaces to a fundus camera body and image capture subsystem. The fundus camera body directs light produced from a first light source into the human eye and that collects and collimates retinal reflections. The adaptive optical module includes a wavefront sensor, controller and phase-compensating optical element. The wavefront sensor measures phase aberrations in the retinal reflections and operates in a closed-loop fashion with the controller to control the phase-compensating optical element to compensate for such phase aberrations to produce phase-compensated retinal reflections for output to the image capture subsystem.

Systems and methods are provided for improving overall vision in patients suffering from a loss of vision in a portion of the retina (e.g., loss of central vision) by providing symmetric or asymmetric optic with aspheric surface which redirects and / or focuses light incident on the eye at oblique angles onto a peripheral retinal location. The intraocular lens can include a redirection element (e.g., a prism, a diffractive element, or an optical component with a decentered GRIN profile) configured to direct incident light along a deflected optical axis and to focus an image at a location on the peripheral retina. Optical properties of the intraocular lens can be configured to improve or reduce peripheral errors at the location on the peripheral retina. One or more surfaces of the intraocular lens can be a toric surface, a higher order aspheric surface, an aspheric Zernike surface or a Biconic Zernike surface to reduce optical errors in an image produced at a peripheral retinal location by light incident at oblique angles.

There is now provided a method for determining vision defects and for collecting data for correcting vision defects of the eye. The method comprises projecting an image into the eye of the patient with an adaptive optical system having adaptive optical elements. The optical characteristics of the optical elements can be individually changed by an electrical signal. The presence of distortions of the image as perceived by the patient is determined by interaction of the patient with the examiner. By way of an electronic control system the optical characteristics of the adaptive optical elements are changed through outputting of an electrical signal to obtain a modified image with minimized distortions in the eye of the patient. The optical characteristics of the adaptive optical elements, as modified, are determined and vision correcting data for the eye being examined are computed from the optical characteristics of the adaptive optical elements, as modified. The method not only takes into consideration the aberrations of the optical imaging system but also the properties of reception and signal processing in the human brain. The method is further characterized in that the correction data for the aberrations of the human eye that impair the vision can be obtained by a measuring method that is actively physiologically evaluated beforehand. There is also provided an apparatus for determining vision defects and for collecting data for correcting vision defects.

It is possible to estimate optical characteristic according to a pupil diameter in daily life of an examinee, correction data near to the optimal prescription value, eyesight, and sensitivity. A calculation section receives measurement data indicating refractive power distribution of an eye to be examined and pupil data on the eye and calculates lower order and higher order aberrations according to the measurement data and the pupil data (S101 to 105). For example, a pupil edge is detected from the anterior ocular segment image and a pupil diameter is calculated. By using this pupil diameter, lower order and higher order aberrations are calculated. According to the lower order and higher order aberrations obtained, the calculation section performs simulation of a retina image by using high contrast or low contrast target and estimates the eyesight by comparing the result to a template and / or obtains sensitivity (S107). Alternatively, according to the lower order and the higher order aberraations obtained, the calculation section calculates an evaluation parameter indicating the quality of visibility by the eye to be examined such as the Strehl ratio, the phase shift (PTF), and the visibility by comparison of the retina image simulation with the template. According to the evaluation parameter calculated, the calculation section changes the lower order aberration amount so as to calculate appropriate correction data for the eye to be examined (S107). The calculation section outputs data such as the eyesight, sensitivity, correction data, and the simulation result to a memory or a display section (S109).

An improved ophthalmic instrument including an extended source producing light that is formed as an image on the retina of the human eye and reflected there from to produce retinal reflections derived from the extended source, and a wavefront sensor that estimates aberrations in the retinal reflections. The wavefront sensor includes a plurality of subapertures that form a plurality of images of the extended source from the retinal reflections, an imaging device that captures the plurality of images and outputs image data representing the images, and an image processing computer that generates an estimate of the gradient field of the retinal reflections by applying image correlation techniques in the digital domain to the image data. The image processing computer preferably generates an estimate of the local tilt of the retinal reflections incident on a given subaperture by deriving a correlation product for a given image formed by the given subaperture and identifying a peak correlation point of the correlation product. The dimensions of the image of the extended source formed on the retina of the human eye is preferably larger that a diffraction limited spot yet small enough so that different parts of the image do not experience substantially different aberrations while passing through the eye. In addition, the angular size of the image of the extended source is preferably limited so that the plurality of images formed by the subapertures do not overlap.