Topology guided ocular lens design

A method for designing and manufacturing a lens including one or more characteristics of a lens optics without applying a trial lens to a patient's eye, comprising:

• a. creating a first computer model containing an optical source, an eye with a three-dimensional model of a corneal front surface of the patient's eye as provided by a topographer, and a Reference Surface placed behind the corneal front surface within the eye, where the Reference Surface may be planar or curved, and further:
• i. when the patient requires corrective lenses, or eyeglasses, to produce a sharp image on their retina:
• inserting a corresponding corrective lens between the optical source and eye in the first computer model;
• tracing rays from the optical source, through air, to a front surface of the corrective lens;
• using the three-dimensional shape of the front surface of the corrective lens, applying Snell's law at a front surface air-lens boundary to determine a path of the optical rays within the corrective lens;
• and
• using the three-dimensional shape of a back surface of the corrective lens, applying Snell's law at a back-surface lens-air boundary to determine a path of the optical rays as they travel from the back surface of the corrective lens to the front surface of the cornea;
• ii. when the patient does not require corrective lenses, or eyeglasses, to produce a sharp image on their retina, then without inserting a corrective lens into the first computer model:
• tracing optical rays directly from the optical source, through air, to the front surface of the cornea;
• iii. determining a path of the optical rays from the front surface of the cornea to a Reference Surface placed within the eye, and using the three-dimensional shape of the front surface of the cornea and the Reference Surface, applying Snell's law at the front surface air-cornea boundary and at any material boundaries within the eye lying between the cornea and the Reference Surface;
• and
• iv. storing the path of the optical rays traveling from the source to the Reference Surface as a Reference Ray Set;
• b. creating a second computer model containing the same optical source, eye, and Reference Surface as in the first computer model, by placing the optical source the same distance from the eye as in the first computer model, and placing the Reference Surface at the same location within the eye as in the first computer model, and within the second computer model further:
• i. placing a scleral lens over the eye in the second computer model, and filling a gap between the cornea and back surface of the scleral lens with a model of a fluid;
• ii. inserting a subset of optical rays from the Reference Ray Set that lie inside the eye between the cornea and Reference Surface in the first computer model into the second computer model, and placing the rays of this subset in the identical location within the eye as in the first computer model.
• iii. assuming the rays in the second computer model now originate at the Reference Surface and travel out of the eye, and using the three-dimensional shape of the front surface of the cornea, the index of refraction of the cornea, and the index of refraction of the fluid, applying Snell's law to the cornea-fluid boundary to determine the path of the optical rays as they travel from the front surface of the cornea through the fluid to the back surface of the scleral lens;
• iv. when the first computer model contains a corrective lens:
• applying Snell's law to the front and back surfaces of the scleral lens optics, adjusting the three-dimensional shape of the front and back surfaces of the lens so that the optical rays in the second computer model approximate, as closely as possible within the limits specified by Snell's Law, the optical rays in the first computer model, over a shared region specified by the Reference Ray Set between the optical source and corrective lens in the first computer model;
• v. when the first computer model does not contain a corrective lens:
• applying Snell's law to the front and back surfaces of the scleral lens optics, adjusting the three-dimensional shape of the front and back surfaces of the lens so that the optical rays in the second computer model approximate, within the limits specified by Snell's Law, the subset of the Reference Rays in the first computer model, over the shared region specified by the distance between the front surface of the scleral lens and optical source in the second computer model;
• and further wherein the lens optics are installed into an optical region of a scleral lens,
• and the method further comprising:
• determining characteristics of the scleral lens, including:
• an optical region, a transition region, and a bearing surface,
• the optical region focusing incoming light into the eye,
• the transition region connecting the optical region to the bearing surface,
• the bearing surface comprising a region of the lens that rests on a surface of an eye,
• the bearing surface further defined as an array of independent data points conforming to the three-dimensional data point positions of the eye extracted from the topographer,
• and with
• each data point used from the topographer representing an independently measured x, y, z location on the surface of the eye,
• a spatial relationship between the data points used from the topographer accurately representing a true topology of the eye, compensated for saccadic or motion blur artifacts that occur during acquisition of the data points,
• a sampling density of the data points used from the topographer and a sampling density of the data points on the bearing surface of the lens being sufficiently high to characterize anomalies anywhere in the eye,
• and such that
• the resulting lens is a scleral lens that conforms to or vaults over said anomalies anywhere on the eye,
• lens optics in the optical region are vaulted over a cornea of the eye to create a fluid reservoir between a back surface of the optics and the cornea,
• the bearing surface either (i) resting solely on a sclera and conforming to a three-dimensional shape of the sclera, or (ii) straddling a limbus, such that the bearing surface rests partially on and conforms to the three-dimensional shape of sclera and rests partially on and conforms to a three-dimensional shape of the cornea, and containing:
• the bearing surface intentionally raised over at least one area in the eye topology under the lens bearing surface, and/or at least one raised gap formed in the bearing surface, allow free flow of tears in and out of a region covered by the lens.

A method to design and manufacture a contact lens from topology data compensated for artifacts resulting from at least one of saccadic and/or random eye motion that occurs during acquisition of the topology data comprising:

• a. operating a topographer to obtain topology data including a three-dimensional (3D) model of an eye in which a two-dimensional (2D) video camera image of the eye, with brightness intensity values representing clinically visual features of the eye transformed into the 3D model, with x, y, z coordinates and brightness intensity values provided for every pixel in the 3D model, and in which the clinically visual spatial features in the 3D model have corresponding clinically visual spatial features on the eye, corrected for any changes in position of the eye relative to the camera during acquisition of the topology data,
• b. the brightness intensity values in the 2D video camera image and the 3D model each being in a visual spectrum of a human eye between 400 nm and 700 nm;
• c. rendering a representation of the 3D model of the eye to enable determination of a lens design for and placement of the contact lens by mapping visual features on the eye to spatial locations on the lens, wherein the visual spatial features on the eye include at least one of a pupil, iris, limbus, blood vessel, or injury;
• d. establishing the design of the contact lens from such visual features;
• and
• c. three-dimensional printing or machining of the contact lens using the design.

A method for obtaining a design for and manufacturing of a contact lens that is not affected by orientation of an eye relative to an axis of a camera and a topographer used for obtaining measurement data of the eye, the method comprising:

• a. operating the topographer to obtain a 3D model of the eye wherein clinically visual features from a two-dimensional (2D) video camera image of the eye are mapped to a same location in the 3D model of the eye independent of a time and an orientation of the eye relative to the axis of the video camera and topographer, with x, y, z coordinates and brightness intensity values provided for every pixel in the 3D model;
• b. brightness intensity values of the visual features on the 3D model being in a visual spectrum of a human eye between 400 nm and 700 nm;
• c. rendering a representation of the 3D model of the eye to enable determination of a lens design for and placement of the contact lens by mapping one or more clinically visual features in the eye, as identified by a human operator, to spatial locations on the lens, independent of orientation of the eye relative to the axis of the camera and topographer;
• d. establishing the design of the contact lens from such visual features, including at least a bearing surface upon which the lens rests;
• and
• e. three-dimensional printing or machining of the contact lens using the design.