72 results about "Corneal topography" patented technology

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.

A system measures a corneal topography of an eye. The system includes a group of first light sources arranged around a central axis, the group being separated from the axis by a radial distance defining an aperture in the group; a plurality of second light sources; a detector array; and an optical system adapted to provide light from the second light sources through the aperture to a cornea of an eye, and to provide images of the first light sources and images of the second light sources from the cornea, through the aperture, to the detector array. The optical system includes an optical element having a focal length, f. The second light sources are disposed to be in an optical path approximately one focal length, f, away from the optical element.

Lenses are designed using the corneal topography or wavefront measurements of the eye derived by subtracting the optical power of the eye after orthokeratology treatment from the optical power before orthokeratology treatment.

A method of obtaining a retro-illumination image using the beacon from an ocular wavefront path and the camera for the corneal topography path of the combined system. A digital image of the retro-illuminated view of the IOL, iris pattern and sclera is obtained. An interactive display of the retro-illuminated image is presented to the user to allow them to identify the orientation marks on the IOL. These marks identify the orientation of the IOL and an overlay line can be used to display this orientation. In addition, a 360 degree overlay can be used to enhance the display of this orientation line.

The invention relates to a design method of free-form surface glasses based on a wave-front technology, which has the technical characteristics that length data of each part of an eye axis is substituted into an eye optical model; a cornea surface curvature and a corneal topography data replace the eye model; wave-front aberration data of actual human eyes is converted into a corresponding value under photopic vision; an individualized eye model which accords with an actual human eye visual property is established; a lens is arranged in front of the individualized eye model; the lens and the individualized eye model are considered as a uniform lens-eye optical system and a certain visual field angle is arranged for the system; a plurality of structures with different angles are arranged for the lens-eye optical system; and the free-form surface glasses according with an individual eye visual property, and the diopter and the structural parameters thereof are calculated. The free-form surface lens obtained by the design method disclosed by the invention, low-order aberration of the eyes can be corrected and high-order aberration can be better corrected; and the design method has the advantages of simplicity and convenience for designing, objectiveness and accuracy, and high precision.

The invention discloses a corneal topographic map discrimination method and a corneal topographic map discrimination system based on deep learning. A corneal topographic map obtained in the prior artis preprocessed to obtain corneal topographic feature data capable of being processed by a corneal topographic map discrimination model. The corneal topographic feature data is input into the cornealtopographic map discrimination model, and a corneal morphology result is obtained through the corneal topographic map discrimination model. The corneal topographic map is analyzed through the cornealtopographic map discrimination model to determine the morphological result of the corneal topographic map, a doctor can directly determine the corneal morphology according to the result output by thecorneal topographic map discrimination model, and the prediction accuracy is high. According to the corneal topographic map discrimination method and system based on deep learning provided by the invention, the trained convolutional neural network model is used for carrying out morphological discrimination on the corneal topographic map, and the problem that a corneal morphological discriminationtechnology for carrying out deep learning processing analysis on the corneal topographic map does not exist in the prior art is solved.

Systems and methods for treating a tissue of an eye with a laser beam include at least one processor that determines angles between a curved surface and a laser beam, controlling an ablative treatment in response to the angles. Angles between a surface of a cornea and a laser beam may be mapped over a treatment area. A mapped area may include an apex of a cornea displaced from a center of a pupil of an eye. Ablation properties may be determined locally in response to the incident angle of a laser beam with respect to a local slope of a tissue surface. The treatment area may be ablated using local ablation properties to form a desired surface shape.

A system includes a model eye and an optical measurement instrument, which includes: a corneal topography subsystem; a wavefront sensor subsystem; and an eye structure imaging subsystem. The subsystems may have a common fixation axis, and be operatively coupled to each other via a controller. The optical measurement instrument may perform measurements of the model eye to verify correct operation of the optical measurement instrument for measuring one or more characteristics of a subject's eye. The model eye may include an optically transmissive structure having a front curved surface and an opposite rear planar surface, and a material structure provided at the rear planar surface of the optically transmissive structure and having a characteristic to cause a speckle pattern of a portion of a coherent light beam that is directed back out the front curved surface of the optically transmissive structure to have a bright-to-dark ratio of less than 2:1.

The invention provides a method for measuring diopter and drawing a corneal topography diagram based on a Placido plate. The method comprises the steps of: (1) calculating data of the diopter of every ring based on the Placido plate; (2) respectively smoothing all data points xk of every ring to obtain smoothed data points; and (3) performing reverse distance interpolation on all the smoothed data points to obtain the diopter. Finally, the corneal topography diagram is drawn according to the diopter. The refraction index of a corneal front surface can be continuously and truly reflected, and the problems of large diopter fluctuations and non-continuous corneal topography diagram of the prior art can be solved.

A method of blink detection in a laser eye surgical system includes providing a topography measurement structure having a geometric marker. The method includes bringing the topography measurement structure into a position proximal to an eye such that light traveling from the geometric marker is capable of reflecting off a refractive structure of the eye of the patient, and also detecting the light reflected from the structure of the eye for a predetermined time period while the topography measurement structure is at the proximal position. The method further includes converting the light reflected from the surface of the eye into image data and analyzing the image data to determine whether light reflected from the geometric marker is present is in the reflected light, wherein if the geometric marker is determined not to be present, the patient is identified as having blinked during the predetermined time.

Methods and apparatus are configures to measure an eye without contacting the eye with a patient interface, and these measurements are used to determine alignment and placement of the incisions when the patient interface contacts the eye. The pre-contact locations of one or more structures of the eye can be used to determine corresponding post-contact locations of the one or more optical structures of the eye when the patient interface has contacted the eye, such that the laser incisions are placed at locations that promote normal vision of the eye. The incisions are positioned in relation to the pre-contact optical structures of the eye, such as an astigmatic treatment axis, nodal points of the eye, and visual axis of the eye.

The embodiment of the invention provides a method and a device for checking and fitting an orthokeratology lens. The method comprises the following steps: obtaining corneal topography data, wherein the corneal topography data comprise corneal eccentricity ratio and flat meridian refractive power; computing the diopter of a location arc of a cornea according to the corneal topography data and a preset correction value; computing the target diopter of a try-on orthokeratology lens according to the computed diopter of the location arc of the cornea and the corneal eccentricity ratio; outputting the target diopter, and reminding to select and try on a corresponding orthokeratology lens according to the target diopter. In such a way, the diopter suitable for the try-on orthokeratology lens canbe computed according to the corneal topography data, so that the checking and fitting accuracy of theorthokeratology lens is increased, and theoretical support is provided for checking and fitting oftheorthokeratology lens.

Selecting an optimal intraocular lens (IOL) from a plurality of IOLs for implanting in a subject eye, including measuring anterior corneal topography (ACT), axial length (AXL), and anterior chamber depth (ACD) of a subject eye; selecting a default equivalent refractive index depending on preoperative patient's stage or calculating a personalized value or introducing a complete topographic representation if posterior corneal data are available; creating a customized model of the subject eye with each of a plurality of identified intraocular lenses (IOL) implanted, performing a ray tracing through that model eye; calculating from the ray tracing a RpMTF or RMTF value; and selecting the IOL corresponding to the highest RpMTF or RMTF value for implanting in the subject eye.

An improved sequential scanning method and apparatus for measuring wavefront aberration involves angularly displacing a measurement beam from a parallel beam striking the corneal surface at a desired location and using the displacement of an image on a detector between the angularly displaced beam and a reference beam to obtain a more accurate wavefront measurement than provided by the displacement between the parallel beam and a reference beam conventionally used for such wavefront aberration measurement. A method and related apparatus for determining a retinal topography relics on using the improved measurement method and apparatus in conjunction with other ocular data to determine changes in the bulbous length of the eye based upon retinal image displacement.

In one aspect, the present invention provides a method of designing an ocular implant (e.g., an IOL), which comprises establishing corneal topography of a patient's eye, e.g., by performing one or more wavefront aberration measurements of the eye, prior to an ocular surgery. The method further includes ascertaining an astigmatic aberration of the cornea that is expected to be induced by the surgery and determining a toricity of a surface of an ocular implant, which is intended for implantation in the patient's eye, so as to enable the implant to compensate for the surgically-induced aberration.

A two-dimensional reflection pattern suitable for corneal topography that uses sinusoidal profiles of both intensity and color values. The technique provides a more robust image processing due to the ability to apply digital band pass filters, continuous data for improved surface reconstruction, and the ability to directly measure the meridian of the reflection pattern source point when the corneal surface normal does not lie in the meridian of the measurement instrument.