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PARTS OF A SIMPLE CAMERA

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Parts Functions

Aperture Allows the light to enter thecamera

Convex

lens

Refracts light ray

Shutter Opens or closes like the eyelid

Diaphragm Changes the size of the apertureFilm Screen where the image is

formed

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Common Eye

Defects

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Myopia (Nearsightedness)

• Inability to see distant objects

clearly

• Image is focused in front of the

retina

• Eyeball is too long

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Hyperopia (Farsightedness)

• Inability to see nearby objects

clearly

• Image is focused in behind the

retina

• Eyeball is too short

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Astigmatism

• An optical defect wherein the

vision is blurred

• Inability to focus causes by the

irregular curve in the lens

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SYMMETRICAL LIGHT REFLEXION

UNEQUAL CRESCENT FORMATION

ASTIGMATISM

NORMAL EYE

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Presbyopia