Abstract: A method for correcting aberrations of the eye applied to an ophthalmic instrument operating with an analysis light beam, including: measurement of aberrations of the eye capable of interfering with the analysis beam, correction of the phase of the wave front of the analysis beam as a function of the measured values of the aberrations, measurement of eye movements carried out independently of the measurement of aberrations, and modification of the correction of the phase of the wave front of the analysis beam as a function of the measurement of eye movements.

Abstract: Detecting position information related to a face, and more particularly to an eyeball in a face, using a detection and ranging system, such as a Radio Detection And Ranging (“RADAR”) system, or a Light Detection And Ranging (“LIDAR”) system. The position information may include a location of the eyeball, translational motion information related to the eyeball (e.g., displacement, velocity, acceleration, jerk, etc.), rotational motion information related to the eyeball (e.g., rotational displacement, rotational velocity, rotational acceleration, etc.) as the eyeball rotates within its socket.

Abstract: Methods and systems for unlocking a screen using eye tracking information are described. A computing system may include a display screen. The computing system may be in a locked mode of operation after a period of inactivity by a user. Locked mode of operation may include a locked screen and reduced functionality of the computing system. The user may attempt to unlock the screen. The computing system may generate a display of a moving object on the display screen of the computing system. An eye tracking system may be coupled to the computing system. The eye tracking system may track eye movement of the user. The computing system may determine that a path associated with the eye movement of the user substantially matches a path associated with the moving object on the display and switch to be in an unlocked mode of operation including unlocking the screen.

Abstract: A system and method are provided for managing data being displayed on at least one monitor screen based on monitoring user's attention in relation to the monitor screen. In one embodiment, upon detecting that the user's attention is leaving at least a portion of a screen, the system may alert the user of such an event. Alternatively, the system could alert the user upon detecting a triggering condition while the user's attention is away from the at least a portion of the screen. The step of alerting the user may include modifying at least a portion of a display on a monitor not being viewed by the user. Additionally, the system may initiate preparation of a report including any data not being viewed by a user during the time period when the user is not viewing a portion of the monitor.

Abstract: A display apparatus includes a light source which emits a beam including visible light forming an image and infrared rays, and a transmissive deflection unit including a first surface facing the eyes of a user and a second surface which is a rear surface of the first surface. The transmissive deflection unit has transmissive characteristics for transmitting the visible light from the second surface side to the first surface side, deflection characteristics for deflecting, toward the eyes of the user, the visible light projected from the light source to the first surface side, and infrared absorption characteristics for absorbing the infrared rays projected from the light source to the first surface side.

Abstract: A visual display characterized by hidden reference illuminators is adapted to emit invisible light for generating corneo-scleral reflections on an eye watching a screen surface of the display. The tracking of such reflections and the pupil center provides input for gaze tracking. A method for equipping and an LCD with a reference illuminator are also provided. A system and method for determining a gaze point of an eye watching a visual display comprising reference illuminators are further provided. The determination of the gaze point may be based on an ellipsoidal cornea model.

Abstract: The invention relates to a system and method for activating a visual control interface, and in particular, for activating a visual control interface using an eye tracking system in a vehicle. A switch is used to activate and deactivate a control section of an eye tracking system in a human-machine interaction control system. The system allows a driver (or operator) of a vehicle to signal the system with selection of the switch to activate or deactivate the control section, thereby providing functional support to the driver when desired, but remaining inconspicuous otherwise.

Abstract: The invention relates to a method for assessing the field of vision, wherein FDF stimuli are produced and detected by a person using the at least one eye to be examined. The invention is based on the object of providing a novel method and a device in order to efficiently assess the field of vision of a person and/or in order to recognize early signs of disease processes, which can lead to limitations in the field of vision. For this purpose, the invention provides that the production of the FDF stimuli is carried out by utilizing a computer-controlled system for the efficient determination of the vision and that the respective FDF stimulus is generated by utilizing an imaging device.

Abstract: A display unit 11 has a display area of a predetermined shape and displays an image on the display area. An image capturing unit 12 generates data of a captured image by capturing an image of an eye 2 of a user in which the display area is reflected. A reference detection unit 21 detects a moving reference point that moves along with the movement of user's eye-gaze and an unmoving reference point that can be assumed as approximately stationary regardless of the user's eye-gaze movement, and generates a vector drawn from the unmoving reference point to the moving reference point as a shift amount V(x,y). An eye-gaze detection unit 22 detects a movement vector ?V(?x,?y) as the user's eye-gaze movement amount based on a reference shift amount Vo(xo,yo) generated in the past and the shift amount V(x,y) currently generated.

Abstract: The method and the apparatus object of present invention refers to a system and A method that create, save and format text documents using a device with gaze control and a system of quick positioning of the cursor. The present invention provides a faster interaction and requires a minimum effort with respect to the state of the art interfaces.

Abstract: A device (1) for determining the visual field comprises a screen (11) for displaying test patterns, an eye monitoring module (13) for capturing eye movements of a patient (20), and a processing module (10) for determining the visual field of the patient on the basis of the eye movements when the test patterns are displayed. The device (1) moreover comprises a mirror (12), which is aligned parallel to the bipupillary line of the patient (20) for determining the visual field, for deflecting the test patterns from the screen (11) to the eyes. The use of the mirror (12) aligned parallel to the bipupillary line of the patient results in a particularly compact design of the device (1) for determining the visual field, which device makes the same geometric and optical measurement conditions possible for both eyes.

Abstract: With some ophthalmological instruments, the patient to be examined or treated needs to gaze in a defined direction. Accordingly, the operator needs the most objective possible information as to whether the patient actually fixates the fixating target or when this may no longer be the case. The invention makes it possible to monitor fixation economically with a short reaction time and with high accuracy. Monitoring of the fixation of an eye is accomplished in an economical manner with a short reaction time and high accuracy through spectroscopic detection of fixation, particularly by identifying a reflection at the fovea or foveola based on different reflectance factors compared to the rest of the retina.

Abstract: The present invention relates to a system, device and a method for objective visual field testing and in particular, to such a system and method in which provides objective chromatic perimetry test or color vision test using a pupillometer.

Abstract: A computer based eye-tracking solution is disclosed. A computer apparatus is associated with one or more graphical displays (GUI components) that may be manipulated based on user-generated commands. An event engine is adapted to receive an eye-tracking data signal that describes a user's point of regard on the display. Based on the signal, the event engine is adapted to produce a set of non-cursor controlling event output signals, which influence the GUI-components. Each non-cursor controlling event output signal describes a particular aspect of the user's ocular activity in respect of the display. Initially, the proposed event engine receives a control signal request from each of the GUI-components. The control signal request defines a sub-set of the set of non-cursor controlling event output signals which is required by the particular GUI-component. The event engine delivers non-cursor controlling event output signals to the GUI-components in accordance with each respective control signal request.

Abstract: Detecting position information related to a face, and more particularly to an eyeball in a face, using a detection and ranging system, such as a Radio Detection And Ranging (“RADAR”) system, or a Light Detection And Ranging (“LIDAR”) system. The position information may include a location of the eyeball, translational motion information related to the eyeball (e.g., displacement, velocity, acceleration, jerk, etc.), rotational motion information related to the eyeball (e.g., rotational displacement, rotational velocity, rotational acceleration, etc.) as the eyeball rotates within its socket.

Abstract: A saccadic motion detection system comprised of an optical system that focuses light reflected or emitted from the subject's eye onto an optical navigation chip, which connects to circuitry configured to convert analog light from the eye to digital representations motion of the eye, including saccadic eye movement and processes the information received thereby.

Abstract: The eye movement, body movement, and/or physiological performance of a subject may tracked while the subject performs a task, such as participating in an activity or sport. The collected data may then be used to identify correlations between the subject's eyesight and the subject's body movement exists and/or physiology. Such a correlation may be analyzed (e.g., over time) to determine any delays or gaps in the subject's ability to track an object, such as a ball, while participating in a sport or other activity. Further, a subject's performance may be compared to data collected from other individuals. The eye movement, body movement, and/or physiological performance data may be used to test and/or train the visual and cognitive abilities of an individual.

Abstract: A sleepiness sign detection apparatus, includes: a head movement detection unit configured to detect a head movement to generate a head movement data; an eye movement detection unit configured to detect an eye movement to generate an eye movement data; an ideal eye movement angular velocity calculation unit configured to calculate an ideal eye movement angular velocity based on the head movement data generated by the head movement detection unit; an eye-rotation angular velocity calculation unit configured to calculate an eye-rotation angular velocity based on the eye movement data generated by the eye movement detection unit; and a sleepiness sign detection unit configured to detect vestibule-ocular reflex (VOR) from the ideal eye movement angular velocity and the eye-rotation angular velocity, and determine a sign of sleepiness based on the vestibule-ocular reflex.

Abstract: A reading meter system and method is provided for identifying the existence and position of text in visual media content and determining if a subject has interacted with the text and/or the level of the subject's interaction with the text. The determination may, for example, be based on data generated from an eye tracking device. The reading meter system may be used alone and/or in connection with an emotional response tool (e.g., a software-based tool for determining the subject's emotional response to the text and/or other elements of the visual media content on which the text appears). If used together, the reading meter system and emotional response tool may both receive, and perform processing on, eye date generated from a common eye tracking device.

Abstract: The present invention relates to an instrument for eye (E) examination, the system including an imaging system (2) to produce images of a portion of the eye to be examined; a projection system (3) to project a stimulus of visible light on a location in the portion of the eye to be examined and a background light on the portion of the eye to be examined; in which the projection system (3) has a telecentric design to uniformly project the stimulus and the background and includes a light source (114) and a movable mirror (112) which is moved according to the location of stimulus projection.

Abstract: An eye-tracking method includes: acquiring an image of an eye of a user captured by an image-capturing module while the user is gazing at a gazing location on a screen module and a pair of light sources emit light toward the eye of the user; determining an angle and an area based on positions of a pupil and two reflected light spots on the eye of the user, wherein the angle and the area correspond to the gazing location; determining coordinates on the screen module based on the angle and the area, wherein the coordinates correspond to the gazing location; and performing an operation associated with the coordinates. An eye-tracking system for implementing the eye-tracking method is also disclosed. A correcting method and a correcting module for the eye-tracking system are further disclosed.

Abstract: An imaging control apparatus which controls an imaging unit configured to capture a tomogram of the fundus of a target eye includes an acquisition unit configured to acquire information representing the direction of a fundus movement of the target eye, an analysis unit configured to analyze the direction of the fundus movement based on the information acquired by the acquisition unit, and a control unit configured to control the imaging unit so as to align the direction of imaging of the imaging unit with the direction of the fundus movement based on the analysis result of the analysis unit.

Abstract: A rapid iris acquisition, tracking, and imaging system can be used at longer standoff distances and over larger capture volumes, without the active cooperation of subjects. Eye reflections from the subjects' eyes are used to steer a high resolution camera to the eyes in order to capture images of the irises. A circular deformable minor driven by one or more annular forces can be used to focus the camera. A circular mirror substrate is mounted by its circumference onto a minor mount and driven by an annular drive element that contacts the minor substrate along a ring. If the annular drive element has a certain diameter relative to the circumference of the mirror substrate, the mirror substrate will be deformed in the shape of a sphere.

Abstract: A system and operational method that supplies visual stimuli to each subject in the form of a virtual environment in which at least the objects of interest have a three dimensional wire frame or mesh frame of a number of polygons that is surrounded with at least one skin or surface; wherein the visual stimuli is presented in a test session to the subject on a display device including an eye tracking sub-system that can effectively track the subject's gaze direction and focus on the display device throughout the test session; wherein unique colors are assigned to the mesh frame and/or an eye tracking skin of each object of interest whereby the system can evaluate the obtained eye tracking data and assign attention data to specific objects of interest resulting in object specific attention data.

Abstract: Axial distances between ocular structures can be measured by focusing an optical unit on focus planes corresponding to the ocular structures and using the distance between focus planes to determine the distance between the ocular structures. The method is particularly useful during eye surgery, e.g., cataract surgery, where the distance between ocular structures, particularly an aphakic pupil, can be used to more accurately predict the effective lens position for an intraocular lens.

Abstract: A method of measuring retinal or visual pathway function comprises stimulating optokinetic nystagmus by presenting a visual stimulus to a patient; modifying a first parameter of the visual stimulus; modifying a second parameter of the visual stimulus; and using the modified visual stimulus to determine a threshold stimulus for optokinetic nystagmus; wherein the first and second parameters are selected from a group of parameters comprising a pattern for the visual stimulus, a width of the visual stimulus, a distance between the visual stimulus and the patient, a spatial frequency of the visual stimulus, a rate of change or temporal frequency of the test face of the visual stimulus, and a contrast between elements of the visual stimulus.

Abstract: The eye movement, body movement, and/or physiological performance of a subject may tracked while the subject performs a task, such as participating in an activity or sport. The collected data may then be used to identify correlations between the subject's eyesight and the subject's body movement exists and/or physiology. Such a correlation may be analyzed (e.g., over time) to determine any delays or gaps in the subject's ability to track an object, such as a ball, while participating in a sport or other activity. Further, a subject's performance may be compared to data collected from other individuals. The eye movement, body movement, and/or physiological performance data may be used to test and/or train the visual and cognitive abilities of an individual.

Abstract: A system and a suitable method for distribution of picture objects which are stored with assigned picture object information in a picture object database. In a media center of the system, user identification data are received which are transmitted to the media center by communications terminals via a communications network. In the media center user interests profiles are defined which, assigned to the received user identification data, are stored in a user interests database. On the basis of the correlation of particular user interests profiles with picture object information, picture objects are selected and transmitted via the communications network to the respective communications terminal from which the received user identification data were transmitted. The current direction of view of a user of the communications terminal is determined and transmitted to the media center, where picture objects which are viewed by the user are identified based thereon.

Abstract: A fundus oculi observation device 1 can form a near-infrared motion image and a color image (still image) of a fundus oculi Ef. The device 1 specifies an image region within the near-infrared motion image corresponding to a region of interest within the color image while the near-infrared motion image is being formed. The device 1 scans with a signal light LS based on the specified image region, thereby forming a tomographic image along the scanning line. According to the device 1, it is possible to determine a region of interest within a still image having a comparatively high image quality, specify the image region within the motion image corresponding to this region of interest, set a measurement site for the tomographic image.

Abstract: This invention relates to methods and apparatus for improving communications between humans and devices. The invention provides a method of modulating operation of a device, comprising: providing an attentive user interface for obtaining information about an attentive state of a user; and modulating operation of a device on the basis of the obtained information, wherein the operation that is modulated is initiated by the device. Preferably, the information about the user's attentive state is eye contact of the user with the device that is sensed by the attentive user interface.

Abstract: This invention discloses an optical object tracking method and system with to up to six degrees of freedom: three translational and three angular coordinates. In the preferred embodiment, the system includes two near-infra-red light sources (e.g., light emitting diode), two cameras, and a digital signal processor. The system performs to tasks: object locking and tracking. For object locking and tracking, a single camera and two off-axis light sources are engaged. For more precise object tracking, two spatially-separate cameras and a single diode are used. In another embodiment, a third camera may be used to separate the locking and tracking tasks. The light sources may have different light wavelengths and may operate in a sequential mode. The cameras may be sensitive over different spectral ranges and may also differ in terms of field-of-view and resolution.

Abstract: A system and method for assessing the function of parts of the nervous system of a subject by measuring the pupillary responses to at least one stimulus ensemble comprising a plurality of individual stimuli; the method comprising: presenting a sequence of selected individual stimuli from the at least one stimulus ensemble to the nervous system of a subject thereby evoking pupillary responses in at least one pupil of the subject, selected individual stimuli being concurrently presented in the sequence, wherein the individual stimuli are each individually balanced such that the pupillary responses evoked by individual stimuli in the ensemble are balanced according to the strength of the neural responses evoked by the individual stimuli; detecting responses of the pupil or pupils evoked by the stimuli using a sensor; and processing the detected responses to relate them to the function of the subject's neural responses to some or all of the individual stimuli of the ensemble.

Abstract: The present invention relates to automatic registration and tracking of the eyes of at least one subject. An optical system, including a lens structure, a mask and an image sensor, receives incoming light from a scene containing the subject and directs at least a portion of this light towards the image sensor, which registers spatially distributed light and thus produces primary data. The mask is to alter a basic optical transfer function of the lens structure and the image sensor into an enhanced optical transfer function, which is substantially less sensitive to variations of an unknown distance between the optical system and the subject than the basic optical transfer function. The processing unit is to receive the primary data and process this data to produce resulting eye-tracking data representing a position estimate of the at least one eye and/or a gaze direction for the at least one eye.

Abstract: The invention refers to A system (10) for registering and tracking the position of a person's eye, in particular for refractive ophthalmic surgery. According to the invention, the system is designed such that eye images containing at least the iris and the pupil of the eye are made at a first wavelength of light and that eye images containing scleral blood vessels are made at a different second wavelength of light. The invention furthermore refers to a corresponding method for registering and tracking the position of a person's eye.

Abstract: An autism diagnosis support apparatus 1 according to the present invention is an autism diagnosis support apparatus that detects a symptom of autism based on a state of a subject looking at a target, including: an eye-gaze point detection unit 2 that detects a line-of-sight direction of the subject looking at the target; a color camera 3 that takes an image of the target; a pupil position detection unit 4 that measures a pupil coordinate of the target; and a data analysis unit 7 that calculates a relationship between the line-of-sight direction of the subject and a pupil position of the target using the line-of-sight direction and the pupil coordinate and outputs the relationship along with the image of the target.

Abstract: A gaze-based three-dimensional (3D) interaction system and method, as well as a 3D gaze tracking system and method, are disclosed. The gaze direction is determined by using the image of one eye of the operator who gazes at a 3D image, while the gaze depth is determined by the distance between pupil centers from both eyes of the operator shown in an image of both eyes of the operator.

Abstract: An apparatus consistent with the present invention comprises a sensor for receiving a signal representing eye tremor and a processor for monitoring eye tremor while receiving the signal. A method consistent with the present invention includes receiving a signal representing eye tremor, comparing the received signal representing eye tremor to at least one reference value, and classifying a patient's brain stem function using the comparison of the received signal representing eye tremor to at least one reference value. An embodiment consistent with the present invention includes an ocular micro tremor (OMT) sensor and associated signal processing hardware and software for clinical analyses.

Abstract: A cognitive function training unit including an eye-target showing unit for showing a movable eye-target on a display disposed in front of the subject's eye, an eye movement measuring unit for measuring a position and/or movement of the subject's eye, and a judgment unit for judging whether or not the subject can fixedly look at or follow the eye-target based on the position and/or the movement of the eye-target shown on the display and the position and/or the movement of the subject's eye measured by the eye movement measuring unit, and the eye-target showing unit shows the eye-target repeatedly while changing the position and/or the movement of the eye-target according to a judgment result of the judgment unit. Therefore, it is possible to show a suitable eye-target according to a symptom of a patient, whereby it is possible to conduct training efficiently.

Abstract: A binocular pupillometer apparatus is provided with processing means to calculate the relative afferent pupillary defect (RAPD) in a subject. The RAPD is calculated as the shift required to bring the two pupillary responses of the left and right eyes into coincidence. Where the responses are not parallel, modified pupillary responses are determined having the same area difference between the responses and an average rate of change with respect to stimulation intensity. The RAPD is calculated from the modified pupillary responses rather than the observed responses. Improvements to the pupillometer include a divider positioned between the left and right stimulating channels.

Abstract: An eye-gaze tracking device, which detects a gaze direction of a user based on an electro-oculogram, includes: a drift estimating unit which estimates drift noise included in a set of observation voltages among observation voltages that are electro-oculograms generated in a living body and observed at the plurality of electrodes, based on a component outside an electro-oculography subspace that is an assembly of sets of electro-oculograms theoretically observed at a plurality of electrodes; and an eye-gaze tracking unit which detects la the gaze direction of the user, based on a signal generated by removing, from the observation voltages, the drift noise estimated by the drift estimating unit.

Abstract: A noise reduction device includes: a saccade information obtaining unit that obtains saccade information from an electro-oculography original signal that indicates an electro-oculogram resulting from an eye movement of a user, the saccade information relating to a saccadic movement which is a rapid eyeball movement; a control unit that determines a filter property for reducing noise included in the electro-oculography original signal, on the basis of the saccade information obtained by the saccade information obtaining unit; and a filtering unit that reduces the noise included in the electro-oculography original signal using the filter property determined by the control unit, to output an electro-oculography signal.

Abstract: An electro-oculography measuring device includes: an electro-oculography measuring unit configured to measure an electro-oculography original signal; a view capturing unit configured to capture a view picture; a drift estimation processing unit configured to estimate a drift signal; and a subtractor which subtracts the drift signal from the electro-oculography original signal to output an electro-oculography signal, and the drift estimation processing unit includes: an electro-oculography change amount calculating unit configured to calculate an electro-oculography change amount; a motion vector estimating unit configured to estimate a motion vector of a moving object included in the view picture; a drift change amount estimating unit configured to estimate a drift change amount assuming that a change in a gaze direction follows a motion of the moving object; and a drift estimating unit configured to estimate the drift signal by adding the drift change amount to a past drift signal.

Abstract: The present invention is directed to a system and method of using a hand held occluder, which is visually opaque but transmits infrared light, in combination with an infrared imaging device for measuring deviations of an eye using cornea reflex measurement of a fixation target.

Abstract: The invention relates to a method and an appliance for examination of the retina, with two-dimensional images of the retina being produced. The invention is based on the object of designing the method and the apparatus so as to allow comprehensive examination and diagnosis of the eye retina in a simple manner. The invention proposes that second data items and two-dimensional depth slice images be produced from the retina, and that the position of these second data items be known in the recorded two-dimensional image of the retina, and/or be predetermined on the basis of the two-dimensional image.

Abstract: An SS OCT interferometry device for measuring a sample, in particular from an eye. The device interferometrically generates a measuring signal and from the signal a depth-resolved contrast signal of the sample by spectral tuning of the central wavelength of the measurement radiation of a measuring signal, and has a control unit for this purpose. The device includes a sample motion detector, which provides a motion signal indicating movement of or in the sample, the control unit uses the motion signal to correct the measuring signal with respect to measuring errors that are caused by a movement of or in the sample before or during the generation of the depth-resolved contrast signal.

Abstract: A surgical microscopy system comprises microscopy optics for generating an image of an eye under surgery. A pattern generator generates a pattern to be superimposed with the image. An eye-tracker is provided for tracking a position of the superimposed pattern with respect to the image in case of a movement of the eye. The superimposed pattern comprises pattern elements that are equally distributed on first and second circles of different sizes, in order to give assistance when placing a suture during a corneal transplant. The superimposed pattern may also provide an assistance for orientating a toric intra-ocular lens.

Abstract: The present invention is related to a system for obtaining a fundus image, constituted by optical means implemented in an equipment to observe and photograph the image of the wall fundus (16), comprising a capturing optical means composed by high sensibility digital camera, constituted by an image sensor (2) and focal optical system (3), said digital camera being used to register a captured image by an afocal optical system, composed by a capturing lens (13) and its afocal complement (6); a lighting optical means provided from a arrangement conformed with optical fiber bundle (7), (8), (9) and (10), halogen light source (23) or light emitting diode source (LED); wherein said light beam from the halogen light (23) or light emitting diodes has an annular form when it pass in the anterior part of eyeball (14) and focus in the pupil plan (15); both the means having the optical path partially common over the optical axle (1) from the optical fibers arrangement (7), (8), (9) and (10) to the fundus (16), region in t

Abstract: Featured is a wireless scleral search coil that includes one or more passive, resonant coils and in a particular embodiment two orthogonal, passive, resonant coils, where each coil resonates at a different frequency. Each resonant coil includes a coil-capacitor circuit, each circuit being configured to resonant at a different frequency. Such a wireless scleral search coil is disposed within a biocompatible material that is shaped to conform and rest upon the eye of a subject. Also featured are system including such a wireless scleral search coil, one or more transmitter coils, an assembly of one or more receiver coils and a calculating sub-system for processing signal data to obtain eye measurement information.

Abstract: A retinal scanning image display apparatus includes a light source, a scanning unit that scans a light flux from the light source, a reflective surface that reflects the light flux from the scanning unit, and an ocular unit that guides the light flux from the reflective surface to an eye of an observer. Optical paths of the light flux scanned by the scanning unit intersect at an exit pupil position of the ocular unit, and the image display apparatus causes the scanning unit and the reflective surface to shift so that the optical paths of the scanned light flux toward the same image position are respectively moved in parallel to move the intersecting position of those optical paths. This realizes a small retinal scanning image display apparatus capable of keeping the image position substantially constant even when an observer moves their pupil.

Abstract: The present invention relates to improved ophthalmic diagnostic measurement or treatment methods or devices, that make use of a combination of a high speed eye tracking device, measuring fast translation or saccadic motion of the eye, and an eye position measurement device, determining multiple dimensions of eye position or other components of eye, relative to an ophthalmic diagnostic or treatment instrument.