An autorefractor, which is used to automatically measure the refractive errors in a person's eye, makes use of the Scheiner principle explained below. Parallel rays of light from a distant object are limited to two parallel bundles of light using a disc with two pinholes. For an eye with no refractive error, the rays would be focused on the retina, where only one spot can be observed. (a) For a myopic eye, how many spots will be observed on the retina? (b) Draw a diagram showing how the light rays fall on the retina of a myopic eye? (c) What could be the reason for the observation?

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Structure of Human Eye, Myopia or Near-sightedness | PadhAiPro

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TextStructure of Human EyeMyopia or Near-sightedness

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