Vision in aviaton Flashcards
3D vision distance
3 dimensional vison up to 10m, then becomes 2 dimensional.
Rods vs Cones
Rods work in much weaker light eneryg, such as night, distributed more diely about the retina. Do not register colour, do not allow sharp vision. Better at detecting movement.
Cones receive bright light energy, found near the centre of the retina, allow sharp vision and fine detail, allow colour.
Arc of accute vision
10 degrees per eye, 20 degrees total
20 degrees 2 second rule
Divide area into 20 degree segments. Scan each segment for 2 seconds.
Luminescence
Amount of light comming from an object. Too much luminescence causes glare decreases vision and vision sharpness.
Effects of hypoxia on vision
Visual sharpess, colour, visual brightness reduction.
Effect of G force
Positive G results in decreased bloow flow results in grewing out, loss of periphral vision (tunnle vision), and blurring. Eventually black out.
Time to become fully adapt to low light levels
30 minutes. 50% after 10 minutes. Sudden exposure to bright light restarts cycle.
What causes central blind spot at night
Sparse density of rods in centre of eye.
Autokinetic effect
The appearence that a stationary light source appears to move around
Empty field blindness, low visual stimulus short sightedness, empty field myopia.
short signtedness can occur in scenarios of low visual stimulus. Eye relaxes to natural focal length of 3 to 4 meters. Resolved by periodically looking at far away object
Break off phenomenon
Feeling of being physiologically detatched from surroundings.
Approach to longer runways
tendancy to get too low
Approach to shorter runways
Tendancy to get too high
Approach to uphill runways
Tendancy to get too low
