What is Eye: Definition and 268 Discussions

Eyes are organs of the visual system. They provide animals with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and convert it into electro-chemical impulses in neurons. In higher organisms, the eye is a complex optical system which collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable assembly of lenses to form an image, converts this image into a set of electrical signals, and transmits these signals to the brain through complex neural pathways that connect the eye via the optic nerve to the visual cortex and other areas of the brain. Eyes with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in molluscs, chordates and arthropods.The most simple eyes, pit eyes, are eye-spots which may be set into a pit to reduce the angles of light that enters and affects the eye-spot, to allow the organism to deduce the angle of incoming light. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment and to the pretectal area to control the pupillary light reflex.

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  1. DrClaude

    Stargazing Eye protection while watching a total solar eclipse

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  2. J

    How Does Flickered Light Affect Our Brain's Perceived Contrast and Brightness of Images?

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  3. L

    B How do I calculate the drop force on a cord and eye bolt?

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  4. L

    B Does light ever go from the eye to the image?

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  5. jtbell

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  6. Salmone

    I How does an eye reconstruct an image?

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  7. greg_rack

    Ranking "by eye" bi-material cross sections for strength/stiffness

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  8. kyphysics

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  9. T

    Stargazing How can we see the ISS at 200 miles away with the naked eye?

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  10. PainterGuy

    Medical How does human eye decode different geometric shapes such as circle?

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  11. L

    Does the human eye magnify objects?

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  12. D

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  13. NatanijelVasic

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  14. S

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  15. DarkMattrHole

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  16. George Jones

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  17. Spinnor

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  18. Graeme M

    B The Human Eye as a Detector in Double-Slit Experiment

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  19. Sophrosyne

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  20. S

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  21. F

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  22. S

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  23. Nik_2213

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  24. I

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  25. R

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  26. M

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  27. navneet9431

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  28. T

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  29. Zeynel

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  30. Asmaa Mohammad

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  31. BenAS

    B Is it possible to see sunspots with the unaided eye?

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  32. T

    Differences between hand eye coordination and reflexes

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  33. M

    Light and oxygen acting upon the eye and the lung during the process of Evolution

    Did the evolution of the eye include interaction/reaction with a specific frequency of light? Did the evolution of the lung include interaction/reaction with the air density, humidity, and temperature of its environment?
  34. A

    What Is the Smallest Spot Diameter the Human Eye Can Detect?

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  35. N

    A Basic question about Head-Up Display and Near Eye Display

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  36. G

    I Steam punk, Field of view including the eye

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  37. R

    I If the observable universe was visible to the naked eye....

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  38. T

    Radius of Curvature to Correct Myopia

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  39. Tareq Naushad

    How mirror/camera/tv work without human eye like system?

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  40. B

    How advanced are spy drones used in the military and law enforcement?

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  41. W

    What Is the Correct Name for This Animatronic Eye Mechanism Part?

    Hello All. I'm searching for this part and also have video footage of it in motion. I cannot find it to finish the eye mechanism because I don't know what it's called. Can anyone tell me what it is? I would greatly appreciate it. Even companies dealing in such parts as well as metal...
  42. I

    How many neurons fire in an eye blink?

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  43. Mastico

    Special Ink invisible to the eye

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  44. kolleamm

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  45. S

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  46. J

    Particles with electric charges visible to the human eye?

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  47. A

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  48. B

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  49. A

    Abt seeing the Andromeda Galaxy with the naked eye in future

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  50. wolram

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