Parabolic shape eliminates spherical aberration in telescope mirrors<!-- InstanceEndEditable -->
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<!-- InstanceBeginEditable name="left" -->Spherically shaped lenses and mirrors share a problem: their shape. Parallel light rays that bounce off the central region of a
spherical mirror focus farther away than light rays that bounce off the edges. This results in many
focal points, which produce a blurry image. To get a clear image, all rays need to focus at the same point.
Changing the shape of a mirror from spherical to
parabolic solves the problem. All light rays focus at the same point and the resulting image is sharp and clear.
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