Abstract: The invention may include a fixed lens (perhaps to simulate a cornea), a pair of Stokes lenses, an iris, deformable lens and an array detector. The implementation or construction of the disclosed embodiments follow and/or simulate the anatomy and geometry of an eye. Several optical and practical constraints were overcome by creating equivalent systems.

Abstract: A subjective optometry apparatus subjectively measures optical characteristics of a subject eye. The subjective optometry apparatus includes a light projecting optical system, an optical path switching portion that switches between a first optical path having a first examination distance and a second optical path having a second examination distance, and an examination distance changing portion that optically changes the first examination distance or the second examination distance. Based on examination distance information, the examination distance changing unit causes the optical path switching portion to set an optical path to either the first optical path or the second optical path, and drives a distance changing optical member in the set optical path to optically change the examination distance to an examination distance different from the first examination distance and the second examination distance.

Abstract: A method for determining personalized near addition value for non-presbyopes, including measuring fusional amplitudes and phoria with at least one addition value, on both eyes of a person at a working distance; finding a mathematical function that predicts the change of a pair of fusional amplitudes and phoria as a function of addition value based on the addition value and the measured fusional amplitudes and phoria; and determining the near addition value according to a suitable relationship between the pair of fusional amplitudes and phoria on the mathematical function.

Abstract: The present invention is a glare tester attachment for use with a phoropter, comprising a pair of eye cups, both eye cups each comprising a wall partially enclosing a hollow interior chamber and having a viewing aperture defining a respective viewing line of sight axis for each eye cup, a portion of each wall being provided with a plurality of lights disposed around said line of sight axis. The invention may be incorporated into a phoropter or a hand-held device.

Abstract: A method and system for simulating/emulating vision using intraocular devices or lenses prior to surgery, preferably using multifocal and monofocal intraocular lenses. The invention allows the patient, prior to surgery, to compare the differences in the perception of an image as seen with the intraocular lens and with normal vision, determining which type of lens the patient prefers, and in turn allows the ophthalmologist to measure which provides the better visual performance. The invention comprises a system containing the intraocular lens, called an artificial eye, a lens for transporting the image from the intraocular lens and eliminating the blur introduced by the artificial eye, and at least one telescope or optometer which transports the intermediate image from the intraocular lens onto the patient's pupil. In this manner, the patient is shown how he/she would see after surgery with each type of lens proposed by the ophthalmologist.

Abstract: The invention relates to systems and methods for testing vestibular and oculomotor function. One aspect of the invention provides a vestibular and oculomotor function testing device including a track supported by a plurality of bearings, an engine configured to selectively displace the track, and a head coupling component coupled to the track. The head coupling component is configured to convey a movement generated by the engine to a subject's head in one or more axes.

Abstract: An optometric apparatus for examining visual functions of an examinee's eye includes: a memory for storing prism powers corresponding to the visual functions of the examinee's eye; an output unit; and a control unit for graphically displaying on the output unit normative areas being areas of normative prism powers in addition to information on prism powers of the examinee's eye based on the prism powers stored in the memory.

Abstract: A phoropter having a line of sight for a viewer to see through comprises a lens system in the line of sight, wherein a shape or focal length of at least one lens in the lens system is controllable by means of an electrical signal, electrical field or current. Wavefront sensors of the phoropter detect local tilts of light wavefronts emerging from the eye and generate output signals that are used for controlling the shape or focal length of the at least one lens. Holographic or diffractive elements are used to collect light scattered from an eye of the viewer and image the scattered light to the wavefront sensors. Preferably one or more of the holographic or diffractive elements are away from the line of sight of the viewer. To use the phoropter, light is passed to the lens system, and light scattered by the eye is collected by the holographic or diffractive elements and imaged onto the wavefront sensors.

Abstract: An optometric apparatus for examining visual functions of an examinee's eye includes: a memory for storing prism powers corresponding to the visual functions of the examinee's eye; an output unit; and a control unit for graphically displaying on the output unit normative areas being areas of normative prism powers in addition to information on prism powers of the examinee's eye based on the prism powers stored in the memory.

Abstract: The present invention is a glare tester attachment for use with a conventional ophthalmic instrument, comprising a pair of eye cups, both eye cups each comprising a wall partially enclosing a hollow interior chamber and having a viewing aperture defining a respective viewing line of sight axis for each eye cup, a portion of each wall being provided with a plurality of lights disposed around said line of sight axis. The invention may be incorporated into a phoropter or a hand-held device.

Abstract: A vision testing device for measuring single or multiple visual functions consisting of an internally illuminated hand-held instrument, vision charts, vision correcting and occluding elements, a testing frame for holding combined vision correcting and blocking elements, and modular accessories.

Abstract: An optometric apparatus for examining refractive power of an examinee's eye subjectively, capable of performing highly-precise examination.

Abstract: An optometric apparatus (2) includes a rotary prism (136a, 136b) disposed in front of the eye (E), for adding a prism degree to the eye (E); a rotation device including a pulse motor (181, 184) and a rotation transmitting mechanism (146, 147, 176, 176a, 177, 177a, 178, 179, 182, 183, 185, 186) for transmitting rotation of the pulse motor to the rotary prism, the rotation device being adapted for rotating the rotary prism to change the prism degree; a command device (43a, 43b) for generating a command signal to start and stop the rotation of the rotary prism; and a control unit (60) for controlling the rotation device to drive the pulse motor to rotate at a speed of 5 pulses/sec. or more when the control unit receives the rotation start command signal until when receives the rotation stop command signal, and, to change the prism degree at a speed of 0.1 to 1.0 prism/sec.

Abstract: A subjective ophthalmic refractor of a type comprising a ring-shaped cylinder power scale having an internal gear actuated by a scale drive gear connected to a cylinder power adjustment knob of the refractor is improved by providing a bearing insert within the cylinder power scale. The bearing insert includes radially and axially facing annular bearing surfaces extending about a substantial portion of the scale, and a cut-out region allowing space necessary for the scale drive gear.

Abstract: A subjective ophthalmic refractor comprises a cylinder power adjustment knob for simultaneously actuating a cylinder power scale and an indexable lens carrier drive assembly. The drive assembly includes a gear phasing hub designed to allow a scale marking to be centered in a display window of the refractor and components of the drive assembly to be set in proper rotational orientation as independent operations.

Abstract: A vision tester comprising a front wall and a back wall. Printed matter comprising words appears on the back wall, which is approximately 14 inches (35.6 cm.) from the front wall. The printed matter is exposed to ambient light from the top and front. The front wall has an opening through which the user of the vision tester looks. A plurality of magnifying lenses, of different diopter ratings, are selectively positionable behind the opening. Indicia appear to indicate the diopter rating of each lens. The user of the vision tester can determine the diopter rating of the appropriate lens needed for reading by determining which lens renders the printed matter clear and readable.

Abstract: A presbyometer for aid in selecting the appropriate strength of over-the-counter (OTC) reading glasses is disclosed. The device comprises a view assembly with a pair of rotational lens wheels. The lens wheels each have a plurality of spaced apart apertures, each having a lens of differing dioptric strength. A user looks through the first lens on each lens wheel toward a back plate having a visual target. The lens wheels are rotated, thereby bringing a lens of increasing Diopter strength into exposure. When the user can adequately read the stimulus, the correct level of Diopter strength correction is identified and corresponding OTC glasses are purchased. A ocular width adjustment means is also disclosed.

Abstract: A phoropter comprises two observation channels, in each of said observation channels a plurality of disk-shaped mounts, rotatably seated about at least one axis, for mounting optically effective members and drive means for rotating said mounts. The drive means are piezoelectric motors, each of which is, on the one hand, connected to a base and, on the other hand, provided with a driving end portion, preferably a driven member which executes a rotating motion. The driven member is, compared to the piezoelectric motor, of small design.

Abstract: Two identical plates somewhat in the shape of very large eyeglass frames sandwiching two rotable discs, one for each eye, form the front section of the device. Each disc has a series of magnifying lenses of increasing power which can be brought into the eye openings in the plate when the discs are rotated and allow the user to focus on a group of alphbetical characters of a predetermined size and at a predetermined distance from the lenses at the end of a view tunnel. The strength of the lenses required for focusing can then be read from the disc where it is clearly indicated next to each lens. These lens strengths correspond to the power of reading glasses sold non-prescription in most drug stores.

Abstract: A device for testing visual contrast sensitivity is disclosed whereby the contrast between a vectographically polarized test symbol and a reference background may be continuously varied by changing the direction of polarization of a polarization analyzer situated along the test axis. The invention is practiced by providing a chart projector or a conventional refractor with a rotatable analyzer.

Abstract: A simple and relatively inexpensive system has been developed for screening people both with normal vision and those with ocular and optic nerve disease using the Pulfrich stereo-illusion phenomenon. The system uses an audio/visual recording showing a ballerina moving in a pendulum fashion in front of a cone. The person to be tested uses a device which sequentially has no filters and filters of varying density whereby the patient with normal vision will see the ballerina moving back and forth in front of the cone and then rotating around the cone clockwise and counter-clockwise. The audio/visual recording may be shown to the person to be tested on a television set or a tv monitor.

Abstract: An illuminator assembly is provided for ophthalmic refractors which is formed as a singular light guide formed in unitary fashion of a transparent polymeric material. The light guide includes a light input portion located adjacent an incandescent light source mounted within the refractor housing. The light guide has transparent output portions which extend uniformly and continuously about the axis scale and further extend to the cylinder power window and the spherical power window. Through the use of a potentiometer/voltage regulator based circuit, the practitioner may alter the intensity of the light propagated to these readout functions by maneuvering a knob mounted upon the battery housing. To improve the characteristics of the illumination, the transparent outputs of the light guide are formed as Fresnel lenses.

Abstract: An ophthalmic dial advancement system for vision testing apparatuses, such as ophthalmic refractors of the type which utilize a single dial sphere control for advancing the lens power of at least one of the lenses positioned within the lens housing. A rotation element is positioned adjacent a portion of the engagement surface of the single dial sphere control so as to facilitate a controlled and sensitive advancement of the single dial sphere control and, in turn, the lenses which are being rotated thereby. A rotation disengagement member is operably attached to a portion of the lens rotation element so as to enable alternatively engaged and disengaged advancement of the single dial sphere control.

Abstract: Apparatus and techniques for measuring and determining the crossed cylinder powers and axes obtained through independent rotation of cylinder lenses are disclosed. Degree scales associated with each lens provide angular measurements for use in connection with a chart or similar apparatus, and in some embodiments determination of the resulting crossed cylinder powers and angles made be made directly from markings included on alternatively designed scales. Unlike many other refractive devices, however, which require use of a digital computer to determine the resulting crossed cylinder power and axis of multiple lenses, the present invention allows such a determination to be made merely by manipulating the positions of the lenses (and viewing entries on the chart as appropriate) and performing simple mathematical operations on the values obtained.

Abstract: A new lens system and method of use for otherwise conventional refractors comprising a five-lens, variable crossed cylinder lens attachment and selectable fixed crossed cylinders which may be placed in the examining optical path. The variable crossed cylinder lens attachment includes two pairs of counter rotating cylinder lenses, each of which may be manipulated independent of the other, and a stationary sphere lens. The assembly also is connected to a computer so that the measurement of astigmatism may be made automatically. In addition, refractive techniques utilizing the disclosed crossed cylinder lens systems are described.

Abstract: An eye examining apparatus has an eye examining lens of an elastic material opposed to an eye to be examined, and control means for causing the marginal portion of the eye examining lens to protrude or sink to thereby change the lens surface of the eye examining lens.

Abstract: A new lens system and method of use for otherwise conventional refractors comprising a synchronized, three-lens, variable crossed cylinder lens attachment and selectable fixed crossed cylinders which may be placed in the examining optical path. The synchronized, variable crossed cylinder lens attachment replaces the Jackson crossed cylinder lens and rotates in step with rotation of the cylinder lens axis. Batteries of strong and weak crossed cylinder lenses replace the strong and weak cylinder lenses of conventional refractors. Refractive techniques utilizing the disclosed crossed cylinder lens systems are also described.

Abstract: A new lens system and method of use for otherwise conventional refractors comprising a synchronized, variable crossed cylinder lens attachment and selectable fixed crossed cylinders which may be placed in the examining optical path. The synchronized, variable crossed cylinder lens attachment replaces the Jackson crossed cylinder lens and rotates in step with rotation of the cylinder lens axis. Batteries of strong and weak crossed cylinder lenses replace the strong and weak cylinder lenses of conventional refractors. Refractive techniques utilizing the disclosed crossed cylinder lens systems are also described.

Abstract: A self-conscious type eye examining apparatus is provided with a Stokes' cross cylinder in a view field window, a spherical lens group having a plurality of spherical lenses selectively disposed in the optical path of the cross cylinder, a first electric rotating device coupled to the cross cylinder to rotate the cross cylinder independently, a second electric rotating device for inserting a predetermined lens of the spherical lens group into the view field window, and a control device for controlling the rotations of the first and second electric rotating devices in a predetermined relation.

Abstract: Disclosed is a refractor of the type having a housing which has patient eye position for viewing along a sight axis extendible therethrough, a pair of superimposed cylinder lens assemblies, means for positioning a particular lens in front of the sight axis, axis control means for controlling the axis of each cylinder lens, a cross-cylinder assembly which is synchronously coupled with said cylinder lens assemblies. The improvement of such type of refractor comprises the positioning means including an internally threaded cylinder axis drive gear having a lock shaft, said gear located outside of the housing and having its lock shaft extending through an opening in the housing coincident with the common axis of both carriers, said shafted cylinder axis drive gear riding upon bearing means disposed between it and the housing. The housing opening for the lock shaft has a sleeve within the housing which circumscribes the opening. There is an annular space formed between the lock shaft and the sleeve.

Abstract: A simulation card for simulating the eye fatigue of a user of a display screen. The simulation card is adapted to mount in front of a lens changing apparatus. An opening in the card permits the eye doctor to examine the patients eyes while the patient focuses on images that surround the opening. A light source behind the card projects through a diffuser screen e.g., frosted "Mylar" plastic film to simulate, on the viewing screen, the images of a display screen.

Abstract: An ophthalmic refractor is provided which is configured for carrying out the Jackson cross-cylinder test. To improve accuracy, an optical encoder is provided in conjunction with each cylinder axis control knob and in conjunction with the lens mount of the cross-cylinder test lens. The cross-cylinder test lens is driven by a d.c. motor and worm gear assembly and a control circuit is provided for selectively energizing the drive motor in correspondence with the settings of the optical encoders. For power mode operation, the control circuit effects motor drive to align the axes of the cross-cylinder lens and pertinent cylinder axis. Correspondingly, for axis mode operation, the control circuit further adjusts the positioning by the motor of the cross-cylinder lens by 45.degree.. Illuminated digital displays are provided on the refractor for direct digital readout of cylinder axis diagnostic data as well as test mode identification.

Abstract: An improved refractor for use in the subjective examination of human eyes. Each half of the refractor includes a plurality of lens supporting disks, a hub assembly for rotatably supporting the disks, and a comb assembly to space the disks along the optical axis. One of the disks supports at least one set of 4 cross cylinder lenses. Each disk is coupled to a stepping motor for selective rotation. Each motor is, in turn, supported by a bracket which permits rotation equivalent to a partial motor step to insure alignment of the optical elements supported on the disks with the optical axis. The cylinder lenses supported on the disks are also rotated by a stepping motor. The Risley prisms of each half of the refractor are always positioned on the optical axis and rotated by stepping motors.

Abstract: An improved refractor for use in the subjective examination of human eyes. Each half of the refractor includes a plurality of lens supporting disks, a hub assembly for rotatably supporting the disks, and a comb assembly to space the disks along the optical axis. One of the disks supports at least one set of 4 cross cylinder lenses. Each disk is coupled to a stepping motor for selective rotation. Each motor is, in turn, supported by a bracket which permits rotation equivalent to a partial motor step to insure alignment of the optical elements supported on the disks with the optical axis. The cylinder lenses supported on the disks are also rotated by a stepping motor. The Risley prisms of each half of the refractor are always positioned on the optical axis and rotated by stepping motors.

Abstract: An improved refractor for use in the subjective examination of human eyes. Each half of the refractor includes a plurality of lens supporting disks, a hub assembly for rotatably supporting the disks, and a comb assembly to space the disks along the optical axis. One of the disks supports at least one set of 4 cross cylinder lenses. Each disk is coupled to a stepping motor for selective rotation. Each motor is, in turn, supported by a bracket which permits rotation equivalent to a partial motor step to insure alignment of the optical elements supported on the disks with the optical axis. The cylinder lenses supported on the disks are also rotated by a stepping motor. The Risley prisms of each half of the refractor are always positioned on the optical axis and rotated by stepping motors.

Abstract: An ophthalmic instrument having a cylindrical test lens and a cross cylinder lens which are adapted to be placed in an examining optical path. The cross cylinder lens is mounted on a lens tube which is rotatably mounted on a swingable lever about a pivot axis. A gear train is provided between the lens tube for the cross cylinder lens and a rotatable part for rotating the cylindrical test lens so that the cylinder axis of the cylindrical lens be rotated about the optical axis of the examining optical path by rotating the lens tube.