65 results about "Fixation (visual)" patented technology

Alteration of a fixation or peripheral stimulus displayed on a computer-driven display allows a human subject to maintain extended visual fixation upon the resulting dynamic stimulus. The fixation is presented upon the display and the stimulus is altered to allow resensitization of the subject's retina, thereby allowing prolonged visual fixation upon the resulting dynamic target. A dynamic stimulus may utilize a frequency doubling illusion.

A subject (12) observes an image on a display (10). A control (18) produces a fixation image at a selected position in the display, followed by a stimulus spaced from the fixation image. An eye position sensor (14) detects a saccade movement towards the stimulus. The stimulus is then replaced with a fixation image and the cycle repeated. The time taken to saccade plus the intensity of the stimulus are used to produce a retinal map of field of vision, or to assess other characteristics of the subject.

A system or method for measuring human ocular performance can be implemented using an eye sensor, a head orientation sensor, and an electronic circuit. The device is configured for measuring vestibulo-ocular reflex, pupillometry, saccades, visual pursuit tracking, vergence, eyelid closure, dynamic visual acuity, retinal image stability, foveal fixation stability, focused position of the eyes or visual fixation of the eyes at any given moment and nystagmus. The eye sensor comprises a video camera that senses vertical movement and horizontal movement of at least one eye. The head orientation sensor senses pitch and yaw in the range of frequencies between 0.01 Hertz and 15 Hertz. The system is implemented as part of an impact reduction helmet that comprises an inner frame having interior pads configured to rest against a person's head and one or more shock absorption elements attached between the inner frame and the spherical shell that couple the spherical shell to the inner frame. The spherical shell has a circular geometry, that when viewed horizontally at its horizontal midplane, includes a center point that is the rotational center of the spherical shell. The one or more shock absorption elements are sized to provide greater spacing between the inner frame and the spherical shell at the sides and rear of the spherical shell than at the front of the spherical shell. The one or more shock absorption elements are sized to configure the alignment of the rotational center of the spherical shell with the proximate rotational center of the wearer's head.

Systems, devices, and methods are described for assessing the risk of developmental, cognitive, social, or mental abilities or disabilities in very young patients (e.g., in the first 2-6 months of life). Generally, the decline in visual fixation of a subject over time with respect to certain dynamic stimuli provides a marker of possible abilities or disabilities (such as ASD). The visual fixation of the subject is identified, monitored, and tracked over time through repeated eye tracking sessions, and data relating to the visual fixation is then analyzed to determine a possible increased risk certain conditions in the subject. A change in visual fixation as compared to similar visual fixation data of typically-developing subjects or to a subject's own, prior visual fixation data provides an indication of a developmental, cognitive, or mental ability or disability.

A retinal imaging system includes an eyepiece lens assembly, an image sensor, a dynamic fixation target viewable through the eyepiece lens assembly, and a controller coupled to the image sensor and the dynamic fixation target. The controller includes logic that causes the retinal imaging system to perform operations including: acquiring a first image of the eye, analyzing the first image to determine whether a lateral misalignment between the eye and the eyepiece lens assembly is greater than a threshold misalignment, in response to determining the lateral misalignment is greater than the threshold misalignment, adjusting a visual position of the dynamic fixation target to encourage the eye to rotate in a direction that compensates for the lateral misalignment, and acquiring the retinal image of the eye while the eye is encouraged to rotate towards the direction that compensates for the lateral misalignment.

The field of the invention relates to systems and methods for ophthalmic laser procedure and, more particularly, to systems and methods for dynamic fixation used in the fixation of the eye(s) of a patient during laser-assisted ophthalmic surgery and / or ophthalmic diagnostic and measurement systems where visualization and concentration on a target are desired. The invention generally enhances the alignment between the eye and a laser beam of a laser eye surgery system using visual fixation system and laser delivery optics. The visual fixation system allows a patient's eye(s) to be accurately focused at one or more fixation targets.

A prism prescription value acquisition system that includes a calculation part for numerically transforming a fixation disparity amount (unit: angle), which indicates a degree at which the visual axis is shifted from the central fovea of the retina when a subject conducts visual fixation of a target, into a prism prescription value by multiplying the fixation disparity amount by a coefficient when the fixation disparity amount is within ±4 minutes. Herein, the prism prescription value is calculated according to the following equation: APver=kver*FDver, APhor=khor*FDhor providing that each of coefficients khor and kver satisfies the following conditions: 0.3≦kver≦0.7, 1.4≦khor≦2.0.