Disclosed is an apparatus for measuring subjective ocular refraction including a display device configured to display a least one optotype and a refractive optical system arranged between an eye of a viewer and the display device, the refractive optical system having an optical power that can be varied according to a determined minimum step. The display device further includes a unit for varying optical power designed to generate a variation in the spherical and/or cylindrical optical power, such that the display device and the refractive optical system form a first image of the optotype with a first total optical power and, respectively, a second image of the optotype with a second total optical power, the variation in optical power between the first total optical power and the second total optical power being less than the determined minimum step.

A method is disclosed for testing hearing in infants based on pupil dilation response. It does not require sedation or depend on subjective judgments of human testers. Pupil dilation response to sound is measured by presenting on a display a visually engaging video containing periodic changes; presenting sounds synchronized with the periodic changes of the video; recording images from a camera directed in front of the display, where the camera is sensitive to infrared wavelengths; processing the images to measure pupil sizes; and processing the measured pupil sizes to determine, statistically, the presence of a pupil dilation response to the sounds.

A processing subsystem generates perceived images from information bearing nerve impulses that are transmitted from a subject's eye(s) to a visual processing region of the subject's brain along one or more nerves in response to the subject viewing a real-world scene. The processing subsystem generates display images based on the perceived images, and controls a display device to display the display images to the subject. In certain embodiments, the processing subsystem generates the display images by manipulating or modifying the perceived images to include virtual images, and provides a type of virtual pointing on the display images that is used to invoke one or more actions.

A computer implemented method and corresponding computer program product and device determine an indication of a user's acuity level. The methods and devices facilitate performance of acuity tests in a decentralized manner while establishing a desired test accuracy irrespective of a particular type of device or display, to determine the indication in a reliable manner. A computer implemented method includes the steps of: performing an optical acuity test using a control unit in communication with a device display having a predefined resolution; and displaying the optical acuity test on the display. The displayed optical acuity test includes a graphical representation with a discontinuity and prompts the user to identify the discontinuity by providing a response. The control unit and display provide that the optical acuity test is adjusted by generating and displaying the discontinuity based on the response and based on anti-aliasing using one or more display pixels.

A computer implemented method and corresponding computer program product and device determine an indication of a user's acuity level. The methods and devices facilitate performance of acuity tests in a decentralized manner while establishing a desired test accuracy irrespective of a particular type of device or display, to determine the indication in a reliable manner. A computer implemented method includes the steps of: performing an optical acuity test using a control unit in communication with a device display having a predefined resolution; and displaying the optical acuity test on the display. The displayed optical acuity test includes a graphical representation with a discontinuity and prompts the user to identify the discontinuity by providing a response. The control unit and display provide that the optical acuity test is adjusted by generating and displaying the discontinuity based on the response and based on anti-aliasing using one or more display pixels.

A base acoustic emission is directed at an eye, and a return acoustic emission is detected from the eye. Base and return acoustic emissions are compared and differences evaluated to determine a descriptor of intraocular pressure. Also, stereo content is provided to a viewer with vergence depth and/or other features selected to bias the eyes towards therapeutically useful positions, movements, focuses, etc. and/or away from harmful positions, movements, focuses, etc. Therapy may facilitate improvements in eye health through reduction of intraocular pressure, reducing mechanical insult to the optic nerve and/or other structures, reducing muscle strain in eye orientation muscles, reducing forces applied to the eye lens and/or within the associated muscles and ligaments, etc., to benefit glaucoma, myopia, etc. Stereo targets may be presented to align the eyes for other testing. Eye alignment, testing, and/or motion treatment may be combined as an “end-to-end” process.

A base acoustic emission is directed at an eye, and a return acoustic emission is detected from the eye. Base and return acoustic emissions are compared and differences evaluated to determine a descriptor of intraocular pressure. Also, stereo content is provided to a viewer with vergence depth and/or other features selected to bias the eyes towards therapeutically useful positions, movements, focuses, etc. and/or away from harmful positions, movements, focuses, etc. Therapy may facilitate improvements in eye health through reduction of intraocular pressure, reducing mechanical insult to the optic nerve and/or other structures, reducing muscle strain in eye orientation muscles, reducing forces applied to the eye lens and/or within the associated muscles and ligaments, etc., to benefit glaucoma, myopia, etc. Stereo targets may be presented to align the eyes for other testing. Eye alignment, testing, and/or motion treatment may be combined as an “end-to-end” process.

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.

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.

A method for generating an indicator or biomarker of colour perception in a mammalian subject, where the method may include submitting the mammalian subject to a multicoloured dynamic stimulus comprising displaying, on a display device. The method may include controlling a change over time of at least one of the two colours of the multicolour pattern when displaying the dynamic multicolour stimulus, to vary the displayed luminance of this colour (usually several times). The method may include acquiring, by using an image acquisition device, an oscillatory response of a pupil of the mammalian subject. The method may include generating, from the acquired response, a signal representative of the power of the pupil's oscillatory response as a function of the change over time of at least one of the two colours when displaying the dynamic multicoloured stimulus.