Abstract: The method include: (a) displaying at least one dynamic target image of at least one sign over a display area; (b) receiving subjective feedback from the subject indicating that the subject is positioned at a maximum distance of best acuity (MDBA) from the target image, wherein the MDBA is the maximum distance in which the subject recognizes the sign; (c) measuring one or more parameter associated with distance, during the time the subject has reached the MDBA distance, using at least one sensor; (d) estimating the MDBA by estimating the distance between the eye of the subject and the display area in which the target image is displayed by using the sensor data and (e) calculating the refractive error of the eye according to the estimated MDBA and characteristics of the target image.

Abstract: An information processing apparatus includes: a light emitting unit configured to emit light; an optical unit configured to induce an optical influence to the light from the light emitting unit, the optical unit having an astigmatic lens configured to generate astigmatism with a plurality of focal lengths; a detecting unit configured to detect the light emitted in the light emitting unit, radiated outside through the optical unit, and reflected by an object; and a measuring unit configured to measure a distance to the object based on astigmatism generated in the reflection light detected in the detecting unit.

Abstract: A new vision test, incorporating textual and non-textual elements in an image, is configured to demonstrate the effects of low cylinder astigmatism and other sources of blur on visual quality. The elements are designed to be noticeable, relevant, important and engaging. The new vision test may be utilized to supplement conventional vision testing.

Abstract: A system having one or more lenticular units and more supplementary parts without lenticular properties. The lenticular units consist of lenticular plates that are capable of visualizing various clinically relevant examination objects. In all the examination positions, the system may visualize a fixation area that is shown alone or together with clinically relevant examination objects targeted at the examination of clinically relevant visual functions. Supplementary parts with various optical properties may be fixed or be moved relative to the lenticular units. Various clinically relevant examination objects may be visualized for the right eye and the left eye in that the examination objects of the system are provided with different colors or light polarizations and using eyeglasses with a differently colored glass for the right eye and the left eye or with polarization filters with a different direction for the right eye and the left eye.

Abstract: Aspects are disclosed for determining refractive error. In an aspect, a line pattern is displayed to a user, and a distance between the line pattern and the user is ascertained. The line pattern includes a first and second line in which an aspect of the line pattern is varied, and where refractive error is quantified based on the distance and a selected variance of the line pattern. In another aspect, the varied aspect of the line is at least one of a width between the first and second line, a thickness of the first or second line, a darkness of the first line or the second line, or a color of the first line or the second line. An input corresponding to a focused line pattern variance selected by the user is then received, and a refractive error is quantified based on the input and an approximate distance between the line pattern and the user.

Abstract: The present disclosure relates generally to a system and method for determining the refractive error of a patient, more particularly determining the patient's refractive error by using a computerized screen, and providing the patient with a prescription for the patient'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 of a patient. The method includes, separately, for each eye of the patient, determining the astigmatism prescription of the patient via a computerized screen, and determining the power of the corrective lenses prescription of the patient via the computerized screen.

Abstract: A method for generating a visual acuity metric, based on wavefront aberrations (WFAs), associated with a test subject and representing classes of imperfections, such as defocus, astigmatism, coma and spherical aberrations, of the subject's visual system. The metric allows choices of different image template, can predict acuity for different target probabilities, can incorporate different and possibly subject-specific neural transfer functions, can predict acuity for different subject templates, and incorporates a model of the optotype identification task.

Abstract: A wavefront device produces adjustable amplitudes in optical path differences and adjustable axis orientation angles. two substantially identical wave plates have a wavefront profile of at least the third order Zernike polynomial function which are not circularly symmetric, as denoted by Z(i,j) where i?3 and j?0. The wave plates are mounted in rotatable mounts with their optical centers substantially aligned with each other. An subjective wavefront refraction instrument and method are provided to correct low and high order aberrations of the eye, using the adjustable wave plates that have astigmatism and higher order Zernike function optical path difference wavefront profiles.

Abstract: An apparatus for determining spherical and cylinder components of subjective refraction of a patient's vision includes a wavefront measurement device that can produce a measure of quality of vision in a return beam from the patient's eye viewing a target through a corrective test lens in the apparatus. The corrective lenses may be varied and a plurality of measurements of quality of vision may be obtained and analyzed to determine the spherical and cylinder components. Accordingly, the eye examiner may conduct a refraction examination without a subjective response from the patient.

Abstract: In order to examine a degree of monocular diplopia is easily examined in a quantitative manner, a plurality of circular eye marks are seen from a predetermined examination distance with a single eye of a patient to find a particular eye mark whose double vision images are observed to be circumscribed each other, and a degree of monocular diplopia is determined by a view angle of the relevant circular eye mark. Since the eye mark is formed as a circular pattern, a degree of monocular diplopia can be examined irrespective of an axial direction along which double vision images appear.

Abstract: An ophthalmic apparatus for inspecting visual functions of eyes to be examined, providing an optical unit having ophthalmic windows, for respectively placing optical elements in the ophthalmic windows by switching, an object indicating unit for presenting an object to each eye to be examined, a display device having an operation screen for operating the object indicating unit and the optical unit, a program storing device for storing therein programs for controlling the display device, the programs having a common numeric value switching area for effecting the switching between numeric values for respective inspecting items such as a spherical degree, an astigmatic degree and an astigmatic axis, and displaying an operation screen displaying an object presented by the object indicating unit and an input screen inputting reference data for inspecting the eyes to be examined within the numeric value switching area, an input device for inputting an operation command through the use of the operation screen of the

Abstract: The inventive method and apparatus are based on the display of a striped target with constantly accurate contrast to the patient for finding a visual function disturbance associated with such eye diseases as glaucoma or diabetic repinopathy at their earlier stage. A sight target of striped pattern is formed on the screen having a uniform brightness, the striped target is oscillated in the direction orthogonal to the striped pattern while varying the contrast of striped target and showing it to the patient, and the threshold of the pattern contrast which can be recognized visually by the patient is measured.

Abstract: An eye-examining apparatus comprises a first positive lens unit, a negative lens unit, a second positive lens unit, a third positive lens unit and a target mark arranged in the named order from the side of the examined eye. The third positive lens unit is mounted movably along the optical axis. Between the first and second positive lens units there is interposed on astigmatic system rotatable about the optical axis. The negative lens unit, the second positive lens unit and the third positive lens unit are so arranged as to form an image of the mark at a position near the focal point on the target mark side of the first lens unit. The focal point on the examined eye of the composite system composed of the negative lens unit, the second positive lens unit and the third positive lens unit is approximately coincident with the position conjugate with the pupil of the examined eye relative to the first positive lens unit.

Abstract: An inversion spring unit for a thermal overload relay and method for making the same, comprising a support member, a spring plate having a first end, a second end, an elongated central axis, and first and second side portions disposed on opposite sides of the central axis, the side portions being bent towards each other at the first end and attached at the first end to the support member for causing the second end of the spring plate to curve in a first direction away from the central axis, and a lug disposed intermediate the first and second ends for selective engagement with a drive portion to cause the second end of the spring plate to curve in a second direction opposite the first direction.