A method for testing visual characteristics includes a providing step of providing a subject with a test image and a changing step of changing an optical element to be placed between the subject and the test image. The test image includes a first image area containing a color to which rod cells are sensitive, and the first image area is placed in such a manner that light coming from the first image area forms an image on a region outside a central fovea of a retina when the subject is looking at a center of the test image. The optical element set includes a plurality of first optical elements configured to transmit light of a first wavelength band to which the rod cells are sensitive within a visible light band. An optical element that the subject does not feel dazzled by the test image is specified.

Embodiments of the present invention analyze readable text in digital content displayed in a user interface for color deficiencies based on a user profile and determine a first color deficiency is present based on the user profile associated with a user viewing the readable text in the digital content. Embodiments of the present invention identify a first color substitution for the first color deficiency based on the user profile, where the user profile includes a color palette with a plurality of variations of a plurality of recognizable colors by the user and the first color substitution is from the plurality of variations of recognizable colors by the user. Embodiments of the present invention display the first color substitution for the first color deficiency as an overlay on the digital content, where the overlay covers at least the first color deficiency.

An apparatus and method for determining at least one visual refraction feature of a subject by showing a visual stimulus to the subject. The apparatus includes an optical system arranged on an optical path between an eye of the subject and the visual stimulus, the optical system being adapted to provide an optical power that is continuously variable as a function of time (t), a control unit for driving the optical power of the optical system and an input device adapted for recording a response of the subject relative to a sharpness of the visual stimulus seen through the optical system, the control unit being adapted to adjust a speed of variation of the optical power (S) as a function of the response recorded.

An apparatus and method for determining at least one visual refraction feature of a subject by showing a visual stimulus to the subject. The apparatus includes an optical system arranged on an optical path between an eye of the subject and the visual stimulus, the optical system being adapted to provide an optical power that is continuously variable as a function of time (t), a control unit for driving the optical power of the optical system and an input device adapted for recording a response of the subject relative to a sharpness of the visual stimulus seen through the optical system, the control unit being adapted to adjust a speed of variation of the optical power (S) as a function of the response recorded.

An optotype calibration method is disclosed. The optotype calibration method includes steps of: (a) when a first optotype and a second optotype located outside an observable area, moving the observable area from an original position until the first optotype or the second optotype appears in the observable area; (b) adjusting a focus mechanism to make the first optotype and the second optotype close to each other; (c) moving the observable area back to the original position; and (d) repeating the steps (a)-(c) until the first optotype and the second optotype align with each other.

An optotype calibration method is disclosed. The optotype calibration method includes steps of: (a) when a first optotype and a second optotype located outside an observable area, moving the observable area from an original position until the first optotype or the second optotype appears in the observable area; (b) adjusting a focus mechanism to make the first optotype and the second optotype close to each other; (c) moving the observable area back to the original position; and (d) repeating the steps (a)-(c) until the first optotype and the second optotype align with each other.

A method for performing digital measurements by obtaining a first video stream of a user at a first distance to a camera; using an element appearing in the first video stream to generate a transformation factor to convert pixel distance in the first video stream to actual physical distance in the real world; using the transformation factor to obtain a first digital measurement in the first video stream; obtaining a second video stream at a second distance, larger than the first distance; using the first digital measurement and an angular measurement to an item appearing in the second video stream to determine a measurement of the second distance.

A vision testing device includes a light-occluding casing for administering vision tests. A viewing station is coupled to the light-occluding casing so a test subject can see a first digital display housed within the light-occluding casing. A second digital display is external to the light-occluding casing and is configured to receive touch-based input. One or more predetermined vision tests are displayed via the first digital display. The second digital display receives input corresponding to the vision test displayed via the first digital display. The second digital display includes response indicators that can be activated via a swiping motion on the second digital display, and a response is recorded as a result of the swiping motion. Each answer corresponding to a swiping motion is stored and output as a result of the vision test.

A vision testing device includes a light-occluding casing for administering vision tests. A viewing station is coupled to the light-occluding casing so a test subject can see a first digital display housed within the light-occluding casing. A second digital display is external to the light-occluding casing and is configured to receive touch-based input. One or more predetermined vision tests are displayed via the first digital display. The second digital display receives input corresponding to the vision test displayed via the first digital display. The second digital display includes response indicators that can be activated via a swiping motion on the second digital display, and a response is recorded as a result of the swiping motion. Each answer corresponding to a swiping motion is stored and output as a result of the vision test.

An ophthalmologic apparatus includes a visual target projection system that is configured to present a visual target to a subject eye at a predetermined examination distance under a presentation condition according to the examination distance, and a controller that is configured to control the visual target projection system. The controller is configured to control the visual target projection system to present the visual target at a first examination distance for a far-point examination of the subject eye, a second examination distance for a near-point examination of the subject eye, and at least one third examination distance different from the first examination distance and the second examination distance.