Binocularity - Muscle function of both eyes working together
Vision Acuity - Measure sharpness of vision (i.e. 20-20 vision, 20-40 vision, etc.)
Stereo Depth Perception - Relative distance measurement
Color Perception - Color Blindness screening
Vertical Phoria - Muscle posture on a vertical plane
Lateral Phoria - Muscle posture a lateral plane
Horizontal Visual Fields - Measures peripheral vision
An additional Intermediate Screening:
The need for testing of Intermediate Vision, the distances
between 20 and 40 inches has been done rather randomly in the past.
The assumption was good vision at far (20 feet) and near (14 inches)
also meant good vision at intermediate distances. However, machine
operators who operate machinery at arm's length or shortly beyond,
engineers who read dials at these distances and those in occupations
requiring similar vision seemingly were handicapped and often suffered
eye problems because they did not have corrective lenses for this work
distance. The tremendous increase in the use of computers and visual
display terminals, most of which are set beyond the normal reading distance,
has resulted in focusing attention to the eye fatigue problems of the operators
and has emphasized the need for screening at the intermediate distances.
The intermediate screening is conducted using
a lens unit distance of 31.5 inches and is most commonly used as a representation
of work at arm's length.