Refraction and Image Size
Date: Spring 2014
How does refraction make objects appear larger than they are?
Consider two objects at the same distance from you. The larger object appears larger because it takes up more of your view. This is determined by the angle over which the object spans, not by the height of the object. A tree looks much smaller when a kilometer away than when a meter away.
When light from a small object passes through a magnifying lens, the light rays are bent inward toward the central axis of the lens. When your eye receives these rays, they cover a greater angle than what you would see without the lens. This matches the pattern of a larger object, so your brain interprets the image as larger than the original object.
Dr. Ken Mellendorf
Illinois Central College
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Update: November 2011