focusing: Quick Facts

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Facts

Also Known As	ocular accommodation • focussing

Photos

Diagram of a double convex lens bending diverging rays from a star-shaped light source so they converge toward an eye.

The shape of the lens plays an important role in allowing the eye to bring objects into focus. Different types of corrective lenses are used, depending on an individual's ability to change lens curvature for accommodation. Convex lenses produce magnified images of objects, whereas concave lenses produce small images of objects.

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Topics

focal point depth of field focal length lens optical system refraction stereoscopy reflection microscope lens Mirror aberration Binoculars eyeglasses diffraction grating