Eye And Vision Flashcards
Saccade.
Quick simultaneous movement of both eyes between 2 or more phases of fixation in the same direction.
Cones.
Best for central vision.
Intense concentration of rods in middle of eye, good for colour vision.
Rods.
Best for peripheral vision.
Highest concentration around outskirts, best for night vision.
Light And Dark Adaption.
Light - 10 seconds
Dark - cones 7 minutes, rods 30 minutes
What Altitude Above Which Night Vision Is Affected.
5000ft
Colour vision deficiency.
genetic fault later in life.
Some cones don’t work properly (cone defect).
Stays same level.
more common in men, 70:1
Depth Perception.
Non stereoscopic vison brain uses cue to infer depth: Colour, contrast, size, rate of movement.
Astigmatism.
Multiple focal points, where light meets.
Presbyopia.
Long sightedness caused by age.
Cataracts.
Clouding of lens due to age or UV radiation.
Glaucoma.
Pressure rise of the liquid within the eyes.
Insidious onset and concealed progression.
Only detected by eye pressure test.
Flash Blindness.
Blinds, curtains, sunglasses, max cockpit lighting.
Sunglasses.
Thin metal frame, unpolarized, strong, not yellow lenses etc.
Contact Lenses.
Used for long distance in aviation.
Blind Spot.
No Cones or rods.
