Stunning Fish Optics: How Fish See Above the Water

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Fish possess a unique optical ability that allows them to see above the water with a nearly 180-degree field of view due to the refraction of light at the water's surface. This phenomenon occurs because light bends as it moves from air to water, enabling fish to perceive objects above them. Diagrams illustrating light rays can help clarify how these angles of incidence are refracted. However, not all angles are refracted effectively, which limits the fish's view in certain directions. Overall, the discussion highlights the complexities of fish optics and their limitations in terms of vision.
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fish optics*urgent*

i dun get it, someone told me that a fish can see everything above it.how can a fish achieve a 180 degree full view of everything above the water?
 
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Kaluence said:
i dun get it, someone told me that a fish can see everything above it.how can a fish achieve a 180 degree full view of everything above the water?
Draw a diagram showing light rays from air being refracted by the water. Do any angles of incidence not get refracted?

Or try this trick: Imagine the fish has a light bulb on its head! Draw a diagram of the those light rays as they leave the water and refract into the air. Does the light reach every angle of refraction? (Then realize that the answer to this is the answer to your question, since light rays are reversible.)
 
All that I know for sure about the optics of fish is that they make lousy glasses. The scales can scratch your cornea. They most particularly make lousy sunglasses, because they start to stink after they dry out.
 
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