Abstract: The present disclosure relates generally to systems and method for testing and determining corrective lens prescription for a patient. In an example embodiment, a method includes using a hand-portable first electronic device, a second electronic device with a computerized screen, and a server to conduct a vision test for a person. The vision test includes determining, an axis prescription, a cylinder prescription, and a sphere prescription for each eye of the person. A corrective lens prescription is provided for the person based, at least in part, on the determined axis, cylinder, and sphere prescription for each eye of the person.

Abstract: Configurations are disclosed for a health system to be used in various healthcare applications, e.g., for patient diagnostics, monitoring, and/or therapy. The health system may comprise a light generation module to transmit light or an image to a user, one or more sensors to detect a physiological parameter of the user's body, including their eyes, and processing circuitry to analyze an input received in response to the presented images to determine one or more health conditions or defects.

Abstract: A method of determining a geometrical measurement of a retina of an eye, comprising obtaining a two dimensional representation of at least a portion of the retina of the eye (34), deriving a geometrical remapping which converts the two dimensional representation of the retinal portion to a three dimensional representation of the retinal portion (36), using one or more coordinates of the two dimensional representation of the retinal portion to define the geometrical measurement to be taken of the retina on the two dimensional representation (38), using the geometrical remapping to convert the or each coordinate of the two dimensional representation of the retinal portion to an equivalent coordinate of the three dimensional representation of the retinal portion (40), and using the or each equivalent coordinate of the three dimensional representation of the retinal portion to determine the geometrical measurement of the retina of the eye (42).

Abstract: An imaging device for imaging an eye includes an eyepiece, an illumination system, an imaging system, and a controller. The illumination system includes a light source that emits illumination light along an illumination path through the eyepiece to the eye to produce a retinal diffuse reflection and a corneal specular reflection. The imaging system includes a first camera that captures a retinal image based on the retinal diffuse reflection and a first set of optical elements, a second camera that captures a corneal specular reflection image based on the corneal specular reflection and a second set of optical elements. The first camera captures at least some residual corneal specular reflection in the retinal image. The controller subtracts the residual corneal specular reflection from the retinal image based on the corneal specular reflection image.

Abstract: Disclosed herein are methods and apparatus for making a determination about an eye in ambient lighting conditions comprising detecting ambient light reflected out of an eye of a subject from a retina of the eye of the subject and making a determination about the eye of the subject based upon the reflected ambient light.

Abstract: Embodiments of the present invention provide methods and systems for determining an ablation treatment for an eye of a patient. The systems and method may involve determining an ellipsoid shape corresponding to an anterior corneal surface of the patient's eye. The ellipsoid shape may include an anterior portion, a major axis, and an apex, where the major axis intersects the anterior portion at the apex. The systems and method may also involve determining a tilted orientation of the eye, such as when the patient fixates on a target during a laser ablation procedure. The systems and method may further involve determining the ablation treatment based on the ellipsoid shape and/or the tilted orientation.

Abstract: This specification describes technologies relating to biometric authentication based on images of the eye. In general, one aspect of the subject matter described in this specification can be embodied in methods that include obtaining a first image of an eye including a view of the white of the eye. The method may further include determining metrics for the first image, including a first metric for reflecting an extent of one or more connected structures in the first image that represents a morphology of eye vasculature and a second metric for comparing the extent of eye vasculature detected across different color components in the first image. A quality score may be determined based on the metrics for the first image. The first image may be rejected or accepted based on the quality score.

Abstract: A parallel detecting optical coherence tomography (OCT) setup and method, in which the light paths of the illumination of the sample and of the detection of the backscattered light do not use the same apertures. The separation of illumination and detection apertures filters these disturbing reflexes from the backscattered light of the sample and significantly increases image quality.

Abstract: This application discloses a content projection system and a content projection method. The system comprises: a gaze point detection apparatus, configured to detect a gaze point location of an eye; an image generating apparatus, configured to generate a virtual image according to visual information and the gaze point location; and a virtual image projection apparatus, configured to project the virtual image to the fundus according to the gaze point location. According to the system and method in the embodiments of the present application, the gaze point location of a user is detected in real time, an imaging parameter corresponding to the visual information is obtained with respect to the gaze point location, and therefore, the virtual image is generated and projected to the fundus, so that virtual graphic information is better fused with reality information, and the user obtains a better sense of immersion.

Abstract: An ophthalmic treatment system of an embodiment is used for performing therapy on target tissue in a patient's eye. The ophthalmic treatment system comprises, a light source, a delivery system, an obtaining means, a setting means and control electronics. The light source is configured to produce treatment light. The delivery system is configured to deliver the treatment light to the patient's eye. The obtaining means is configured to obtain information acquired by capturing the patient's eye. The setting means is used for setting a position in the patient's eye by using the information obtained by the obtaining means. The control electronics is configured to control the delivery system based on the position set by the setting means.

Abstract: Described herein is a light directing assembly for use in an object analysis system. The light directing assembly includes a plurality of optical relay assemblies. Each optical relay assembly includes at least one optical element configured to relay an interrogation beam from a light transmission system to an object and relay a return beam from the object to the light transmission system, the return beam being generated by reflection or back scattering of the interrogation beam by the object. Each optical relay assembly defines an interrogation angle at which the interrogation beam relayed by the optical relay assembly reaches the object, and an optical path length being the distance from the light transmission system to the object traveled by an interrogation beam via the optical relay assembly.

Abstract: This invention solves the problem that objects in the field of view of reading glasses using multifocal lenses for correcting ocular refractive errors such as presbyopia appear distorted. This image display device is provided with the following: a distance computation unit that computes the distance to a subject in a field-of-view image; a visual-acuity-information acquisition unit that stores visual-acuity information for the user in advance; a corrected-image generation unit that generates and outputs a corrected image on the basis of the field-of-view image and an eye image generated from the field-of-view image, the distance information, and the visual-acuity information; and a display unit that displays the corrected image by superimposing same onto the user's field of view. Since the corrected image is superimposed without the use of lenses, lenses being the cause of the abovementioned distortion, the user can see close objects clearly.

Abstract: A display system has a control apparatus and a display unit that can be worn on the head of a vehicle user. The control apparatus has an input interface for accepting a piece of traffic-relevant information, a transducer for producing an image signal for the display unit taking account of the piece of traffic-relevant information and an output interface for outputting an image signal. The display system is prepared to display the piece of traffic-relevant information by the display unit in a marginal region of a field of vision of the vehicle user. A vehicle has the display system.

Abstract: A method for customizing an electronic image display device having at least one display parameter of variable value includes: a) linking the electronic image display device to a user database, determining and recording at least one value of an evaluation parameter for the visual and oculomotor profile of a user; b) linking the electronic image display device to a display database and making a digital record including a plurality of values for the display parameter which are associated with an electronic image display device; c) selecting an optimum value for the display parameter from among the plurality of display parameters values in the digital record that are associated with the electronic image display device in the display database according to the visual acuity measurement associated with this user in the user database; d) automatically applying the optimum value for this image display parameter to the electronic image display device.

Abstract: An eye examination template for measuring an optic disc can include an x-axis measurement line, a y-axis measurement line, and an optic disc oval. In one aspect, the x-axis measurement line can include a plurality of x-axis measurement marks. In another aspect, the y-axis measurement line can include a plurality of y-axis measurement marks. In yet another aspect, the y-axis measurement line can intersect the x-axis measurement line at a square angle intersection. In a further aspect, the optic disc oval can be centered on the intersection of the y-axis measurement line with the x-axis measurement line. In one aspect, the optic disc oval can correspond with an average optic disc size of a first demographic of a population.

Abstract: An ophthalmological device emits light from a measurement optical system to an eye to be examined and calculates a dimension along the eye axis of a target portion of the eye from interfering light composed of reflected light from the eye and reference light. The measurement optical system includes incidence position changing member that changes the incidence position of light emitted to the eye, and driving unit that drives the incidence position changing member so as to scan at the incidence position of emitted light in a predetermined region of the eye. The predetermined region is a region where a straight line passes through when the straight line radially extended from the cornea apex of the eye is circumferentially moved over a predetermined angle range in the case of the eye is viewed from the front.

Abstract: A system (10) for measuring a physical characteristic of an object (11) using dual path, two-dimensional Optical Coherence Tomography (OCT) includes an extended broadband light source (13) producing an incident light beam (14) and an interferometer (15) having a beam splitter (16) that splits the incident beam into first and second component (17, 18) beams and directs the second component beam (18) on to a moveable mirror (19) for creating an optical path difference between the first component beam (17) and a reflection (20) of the second component beam. A focusing lens (21) having a focal plane (22) focuses the first component beam and the reflection of the second component beam to form a fringe pattern (23) on the focal plane, and a configurable imaging system (25) images the fringe pattern on to a plane (12) of the object to allow two-dimensional measurement of the object without spatial scanning.

Abstract: The present invention refers in general to the measurement of aberrations of the optical system (E) of a living being, in particular human. More specifically, the invention refers to methods and systems for reconstructing a wavefront (W(z,p)) and/or for constructing a refracting error map.

Abstract: A corneal topographer includes: a flat panel display configured to display a light pattern and to project the light pattern onto a cornea of an eye disposed on a first side of the flat panel display; an optical system disposed on a second side of the flat panel display, the optical system being configured to receive and process reflected light from the cornea that passes through the flat panel display from the cornea to the optical system; a camera configured to receive the processed reflected light from the optical system and to capture therefrom a reflected light pattern from the cornea produced in response to the projected light pattern; and one or more processors configured to execute an algorithm to compare the projected light pattern to the reflected light pattern from the cornea, and to produce a topographic map of the cornea based on a result of the comparison.

Abstract: A system and method for determining an objective quality metric for image data collected by a wavefront aberrometer. The method may include quantifying a plurality of characteristics of the image data and calculating the objective quality metric based on the quantified characteristics of the image data. The objective quality metric can be a weighted sum of the quantified characteristics of the image data. The weightings for the weighted sum can be determined based on subjective quality metrics assigned to a set of training image data by a human expert.

Abstract: A method for the treatment of amblyopia comprising the steps of diagnosis and approval of a patient by a medical practitioner, providing access to an eye-training platform for the approved patient and instructions to the approved patient on using the eye-training platform, preparation of a therapy protocol by the medical practitioner, use of the eye-training platform according to the therapy protocol, recordal of patient results, intermediate examination of the patient and review of patient results, further use of the eye-training platform according to a modified therapy protocol, recordal of further user results, and examination of visual acuity and review of user results by the medical practitioner.

Abstract: Device and method for determining an objective eye refraction parameter of a subject depending on a plurality of gaze directions, the device includes elements for ophthalmologically measuring an objective eye refraction parameter of a subject, and elements of visual stimulation of variable proximity and intended to stimulate the visual accommodation of the subject for first and second proximity values. The device includes opto-mechanical alignment elements for carrying out a first optical alignment of the optical axis of measurement on an eye axis in a first measuring position corresponding to a first angle of lowered viewing associated with a first proximity value to take a first measurement of an objective eye refraction parameter of the subject, and a second alignment of the optical axis of measurement on the eye axis in another measuring position corresponding to another angle of lowered viewing associated with another proximity value to take a second measurement.

Abstract: Embodiments of this invention relate to the generation of wavefronts for measurements, diagnostics, and treatment planning for ophthalmic applications. In some embodiments, a wavefront generator generates light having a uniform wavefront, which is focusable on the retina of an emmetropic eye by the normal function of the emmetropic eye. In some embodiments, the wavefront generator can generate light having a custom wavefront which is not focusable on the retina of the emmetropic eye. In some embodiments, the wavefront generator can receive information relating to an optical aberration of the eye, generate a custom wavefront, and project light having this custom wavefront, which in combination with the optical aberration of the eye is focusable on the retina.

Abstract: The present disclosure relates generally to a system and method for determining the refractive error of a person, more particularly determining the person's refractive error by using a computerized screen, and providing the person with a prescription for the person's preferred type of corrective lenses. The system and method do not require the trip or expense of a doctor visit, and are optimized for convenience and cost effectiveness. In a general embodiment, the present disclosure provides a method for determining a corrective lenses prescription for a person. The method includes, separately, for each eye of the person, determining the sphere prescription for the person via a computerized screen and without the use of a refractor lens assembly. Determining the sphere prescription is done, in part, by displaying a sphere figure to the person via the computerized screen and enabling the person to select at least one input, where the input corresponds to a sphere measurement.

Abstract: An ophthalmologic apparatus of an embodiment includes an optical system, a rotational movement amount calculator, a registration unit, a parallel movement amount calculator, a driver, and a controller. The optical system is used to capture a moving image of a subject's eye. The rotational movement amount calculator calculates a rotational movement amount between a first image and a second image included in the moving image. The registration unit performs registration between the first image and the second image in the rotation direction based on the rotational movement amount. The parallel movement amount calculator performs a phase only correlation process on the first image and the second image registered by the registration unit to calculate a parallel movement amount between the first image and the second image. The driver moves the optical system. The controller controls the driver based on the parallel movement amount.

Abstract: The present invention relates to an apparatus for inspecting the fundus of the eye, comprising: —lighting means configured to project a light beam for illuminating the retina of one eye; and —an optical path comprising one or more lenses configured to optically conjugate the retina with a receiving surface of acquisition means configured to acquire one or more images of the retina; and —a beam splitter device configured to divert a part of the light, which is reflected by the retina and directed towards said acquisition means, towards first photosensitive elements; and —a control unit operatively associated with said first photosensitive elements, said acquisition means and said lighting means, said control unit deactivating said lighting means when the light energy received from said first photosensitive elements overcomes a predefined threshold value; and —first LED devices configured to project light targets onto the retina, which the patient must stare to keep the eye still during the examination.

Abstract: Disclosed are a target object information acquisition method and an electronic device. The target object information acquisition method comprises a first infrared transmitter transmitting scattered light to a target area comprising at least one object; a photoreceptor receiving first reflected light output after at least one object reflects the scattered light in a first time period, and generating a depth image corresponding to the target area, acquiring the target image information about a target object; a second infrared transmitter transmitting scattered light to the target area; the photoreceptor receiving second reflected light output after at least one object reflects the scattered light in a second time period, and generating a feature image corresponding to the target area; and acquiring feature information. By means of the time division, the present invention solves the technical problem of a low acquisition rate for target object information in the prior art.

Abstract: A hand-held ophthalmological device includes: a main unit having an ophthalmoscopic optical system configured to project ophthalmoscopic light to an examinee's eye and receive reflection light therefrom to examine or measure an examinee's eye; a detector placed in the main unit and configured to detect a relative deviation between an optical axis of the ophthalmoscopic optical system and the examinee's eye; a deviation compensating optical system placed as a part of the ophthalmoscopic optical system and configured to compensate the deviation; and a drive part configured to drive the deviation compensating optical system based on output from the detector.

Abstract: A tomographic image capturing apparatus includes a fixation lamp configured to guide a line of sight of a subject's eye, and a control unit configured to control a projection position of measuring light according to a predetermined position on a fundus of the subject's eye and a projection position of the fixation lamp.

Abstract: A binocular multiplexing device for a single-channel ophthalmological instrument for objective measurement of at least one vision parameter of a subject, the ophthalmological instrument including elements for generating a single light beam, elements for collecting a measurement beam by reflecting and/or refracting the light beam against the subject's eye and a sensor associated with the single measurement channel.

Abstract: A system includes a first element configured to receive a plurality of color components that are spatially separated, wherein each of the plurality of color components comprises light of a respective wavelength, and to focus the plurality of spatially separated color components onto a first surface of a second element. The system also includes a second element having a first surface and a second surface, wherein the second element is configured to receive the plurality of color components via the first surface, to transmit to the second surface uniform light comprising the plurality of color components in a blended state, and to emit the uniform light via the second surface. The system also includes a slit lamp configured to receive the uniform light.

Abstract: An ophthalmoscope device includes a support structure, an image capture device, and a display device. The support structure is configured to be worn by a subject. The image capture device is configured to capture images of the eye fundus of the subject. The display device is configured to overlay images in the field of view of the subject. The overlaid images are used to align the pupil/fovea orientation axis with the optical axis of the image capture device.

Abstract: A photorefraction ocular screening device for assessing vision and corresponding disorders associated with the human ocular system is provided. More specifically, the present invention provides for a photorefraction ocular screening device employing advanced methods of pupil detection and refractive error analysis. The photorefraction ocular screening device is comprised of an LED arrangement configured with a plurality of irradiation sources serving as visual stimuli, wherein the visual stimuli may be presented in varying illumination patterns to the pupils of an examinee for expanding the range of ocular responses that can be used to determine refractive error.

Abstract: The determination of objective refraction data for an eye of a spectacle wearer, wherein based on measured data for the eye of the spectacle wearer, which determine at least one first set of Zernike coefficients of a wave front aberration for a long accommodation and a second set of Zernike coefficients of a wave front aberration for a short accommodation of the eye, objective refraction data for sphere (SphNcorr), cylinder (CylNcorr) and axis position (AxisNcorr) of the eye for close viewing is determined such that the objective refraction data satisfies equations Sph N corr = M N corr + ( J N , 0 corr ) 2 + ( J N , 45 corr ) 2 , ? Cyl N corr = - 2 ? ( J N , 0 corr ) 2 + ( J N , 45 corr ) 2 ? ? and Axis N corr = 1 2 ? arctan ? ( - J N , 0 corr , - J N , 45 corr ) + ? 2 for a corrected power vector PNcorr for near viewing, wherein said corrected power vector PNcorr corresponds, based on a difference

Abstract: A method and apparatus for modeling a lens of an eye, comprising: measuring the anterior shape of the eye's cornea; determining direct optical measurements of at least one parameter of the cornea and at least one parameter of the lens; determining the refractive index of the cornea; correcting the optical measurements to account for the effect of the refractive index of the cornea on the direct optical measurements; measuring the aberration of the eye; calculating the refractive index of the lens by combining the corrected measurements and the measured aberration; and further correcting the optical measurements of the lens to account the effect of the refractive index of the lens on the direct optical measurements.

Abstract: A tomographic imaging apparatus includes: a light source; an optical splitter unit for splitting light from the light source into reference light and measuring light; a reference optical system including an adjustment unit for adjusting an optical path length of the reference light; a spectral unit for spectrally splitting combined light of the reference light and the return light obtained by irradiating an object to be inspected with the measuring light so as to acquire an interfering signal; a detection unit for detecting an optical path length when a tomographic image of the object is photographed; a storage unit for recording data about a refractive index of a refracting element of the object; and a calculation unit for calculating image data from the interfering signal acquired by the spectral unit based on an actual size using data about the optical path length and the refractive index.

Abstract: An adaptive optical apparatus comprising: a shielding unit configured to shield diffracted light that is generated at an aberration correction unit that is irradiated with returning light, wherein the returning light returns from an object to be examined that is irradiated with light; a detection unit configured to detect an aberration of the returning light through an aperture of the shielding unit; and a control unit configured to control the aberration correction unit based on a detection result of the detection unit.

Abstract: A visual function testing device includes: a visual target image presentation unit that presents a visual target image; a visual target image rendering unit that renders the visual target image to be presented on the visual target image presentation unit; a visual function test item selection unit that selects a visual function test item; a visual target image generation unit that generates a visual target image corresponding to the test item selected by the visual function test item selection unit; a viewpoint distance input unit that inputs a distance between the visual target image presentation unit and a viewpoint of an observer; and a visual angle input unit that inputs an angle to be made by the visual target image and the viewpoint of the observer. Based on the viewpoint distance and the visual angle, a display size and display position of a visual target image are calculated.

Abstract: An eye refractive power measuring apparatus includes a light projecting optical system, a light receiving optical system, a focusing unit, a calibration optical system, a focus control unit, and an arithmetic unit. The arithmetic unit, based on a relation of a control signal obtained when a calibration beam is projected and a calibration value that is an output of a light receiving unit, and a correlation of a calibration value obtained in advance and eye refractive power, calculates a correlation of the control signal and the eye refractive power, and, based on a control signal obtained when measuring beam is projected, a measured value that is an output of the light receiving unit, and the correlation, calculates the eye refractive power.

Abstract: Methods and system for determining a physiological parameter of a subject through interrogation of an eye of the subject with an optical signal are described. Interrogation is performed unobtrusively. The gaze direction of the eye of the subject is determined and an interrogation signal source and/or response signal sensor are moved into alignment with the eye using an actuator to facilitate detection of the signal from the eye of the subject.

Abstract: Methods and systems for determining a physiological parameter of a subject through interrogation of an eye of the subject with an optical signal are described. Interrogation is performed unobtrusively. The physiological parameter is determined from a signal sensed from the eye of a subject when the eye of the subject is properly aligned with regard to an interrogation signal source and/or response signal sensor.

Abstract: A method of tracking a position of an eye is provided. The method of tracking a position of an eye includes converting an obtained image into a binary number image, classifying the corner of the eye, maximum and minimum values of a pupil of the eye, and extracting a feature point from the binary number image on which the binarization step is completed, calculating a distance and inclination between the corner and the pupil of the eye using the feature point extracted through the feature point extraction step, and determining a gaze direction of the eye based on the distance and inclination calculated through the distance and inclination calculation step.

Abstract: A process and an apparatus are proposed for determining optical aberrations of an eye with its optical system including the cornea and the lens. The process includes the reconstructing of wavefront aberrations of the eye as a deviation of the wavefront, determined by the optical system of the eye with a process of aberrometry, with respect to an ideal planar wavefront generated by an aberration-free eye model. A measured ocular length is employed for the aberration-free eye model.

Abstract: A method for noninvasive analysis of a retina includes exposing the retina to one or more first sets of at least three illumination light signals. The at least three illumination light signals each have a different wavelength. The method also includes optically collecting a reflected light signal for each of the at least three illumination light signals of the one or more first sets. Each of the reflected light signals is a portion of the respective illumination light signal reflected by the retina. The method further includes detecting the reflected light signals of the one or more first sets as a function of intensity. The method still further includes determining a first opsin density using the detected intensity of each of the reflected light signals of the one or more first sets.

Abstract: A method of determining a corneal thickness and an apparatus for determining said is provided. The method comprises the following the steps: —illuminating a cornea by a plurality of stimulator point light sources, capturing an image of the cornea comprising reflected images of the stimulator point light sources, obtaining a model representing an anterior surface of the cornea, —constructing a second model representing a posterior surface of the cornea from the image by ray-tracing the reflected images of the stimulator point light sources towards the model representing the anterior surface of the cornea, determining the corneal thickness from the model representing the anterior surface and the second model representing the posterior surface.

Abstract: An imaging apparatus includes a measuring light focusing unit configured to focus measuring light for measuring aberration of an object on the object, an aberration correction unit configured to change a state based on the aberration measured with the measuring light, an imaging light focusing unit configured to focus imaging light for capturing an image of the object on the object, an imaging unit configured to capture an image of the object with the imaging light having passed through the aberration correction unit and the imaging light focusing unit, and a control unit configured to interlockingly control states of the measuring light focusing unit and the imaging light focusing unit.

Abstract: A fundus camera includes a focus target projection unit including a focus target located at a position conjugate with a fundus of a subject's eye, a split optical element configured to split a light flux passing through the focus target, and a focus target illumination light source configured to illuminate the focus target, a fundus photographing optical system including a focusing lens, a focus link mechanism configured to interlockingly move the focus target projection unit and the focusing lens in a direction of an optical axis, at least two lenses located behind a plane optically conjugate with the imaging plane of the fundus photographing optical system and outside an optical axis of the fundus photographing optical system, image sensors respectively located behind the two lenses, and a phase difference detection unit configured to detect a phase difference between the focus target images based on signals output from the image sensors.

Abstract: Methods and apparatuses for a micro-display based slit lamp illumination system are provided. A first optical element is configured to generate a micro-display image including an illuminated area. A second optical element is configured to receive the micro-display image, and focus the micro-display image upon an eye to be examined, wherein light is reflected from the eye as a result of the illuminated area.

Abstract: An ophthalmologic photographing apparatus includes: an optical coherence system for obtaining a tomographic image of an examinee's eye, having an optical scanner for scanning the eye with measurement light and a detector for detecting an interference signal of the light and reference light; an observing optical system for acquiring a front image of the eye; a scan controller for controlling the optical scanner to scan with the light different transverse positions set on the image, and acquire first interference signals at the positions; a display controller for displaying on a monitor an image created in response to the first interference signal; and an image recapture setting unit for setting a rephotographing transverse position in response to an operation signal from an operating unit for the image on the monitor. The scan controller scans the eye with the light at the rephotographing transverse position, and acquires a second interference signal.

Abstract: This invention describes a corneal topographer with a light source to project a pattern light on the cornea, imaging optics for collecting the reflection from the cornea and projecting it on to a photo-sensor, an optical mask to modulate the light beam such that focusing error of the corneal image results in displacement of its spatial spectrum relative to a reference spectrum. Defocus maps, depth-maps and a corneal topogram can be constructed by measuring and processing the spectral displacement corresponding different sub-regions of the cornea. The cornea topographer is compact and inexpensive. The corneal topograph can be used in refractive eye surgery and in contact lens fitting.