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Landolt rings
References
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Landolt rings

medical instrument
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The Information Architects of Encyclopaedia Britannica

The Information Architects maintain a master list of the topics included in the corpus of  Encyclopædia Britannica, and create and manage the relationships between them.

The Information Architects of Encyclopaedia Britannica

Learn about this topic in these articles:

  • cross section of the human eye
    human eye
    / Measurement

    …acuity is measured by the Landolt C, which is a circle with a break in it. The subject is asked to state where the break is when the figure is rotated to successive random positions. The size of the C, and thus of its break, is reduced until the subject…

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    …acuity is measured by the Landolt C, which is a circle with a break in it. The subject is asked to state where the break is when the figure is rotated to successive random positions. The size of the C, and thus of its break, is reduced until the subject…

    Read More