Optec 5000PG, Reference And Instruction Manual

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Divergence:
The process of directing two eyes from a near point to a far point.
Esophoria:
The tendency of the eye to pull inward on the horizontal plane.
Exophoria:
The tendency of the eye to pull outward on the horizontal plane.
Far Point:
Twenty feet to infinity.
Fixation:
Directing the eye so the image centers on the fovea.
Focus:
The point at which light rays will come together after passing through a lens.
Fusion:
Powere of coordination by which images received by two eyes become a single image.
Hyperopia:
Farsightedness, the images focus behind the retina.
Hyperphoria:
When either eye has a tendency to pull up on the vertical plane.
Intermediate Vision:
Vision which focuses at some point beyond 18 inches or 45 centimeters (Near Point) and less than 20 feet or 6
meters (Far Point).
LUX:
The unit for measuring of glare.
Malingerer:
A person who pretends to have a vision problem.
Mesopic:
Pertaining to illumination between the photopic and scotopic ranges.
Monocular:
Seeing with only one eye.
Muscle Balance:
The coordination of muscles allowing two eyes to work together on the vertical and lateral planes.
Myopia:
Nearsightedness; has problem seeing at a distance; images focus in front of the retina.