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Sigmund Exner
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Sigmund Exner

Austrian physiologist

Learn about this topic in these articles:

research on superposition eyes

  • details of the mammalian eye
    In photoreception: Image formation

    In the 1890s Austrian physiologist Sigmund Exner was the first to show that lens cylinders can be used to form images in the eye. He discovered this during his studies of the ommatidia of the horseshoe crab Limulus.

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  • details of the mammalian eye
    In photoreception: Refracting, reflecting, and parabolic optical mechanisms

    …was discovered by Austrian physiologist Sigmund Exner in the 1880s. He reasoned that the geometrical requirement for superposition was that each lens element should bend light in such a way that rays entering the element at a given angle to its axis would emerge at a similar angle on the…

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