Fundamentals of Medical Imaging

What is an image? An optical appearance; a mental representation an idea or conception. The term image may be applied to a picture such as a photograph a painting or a sketch which has a real physical existence. May also be applied to an idea or concept which has a mental rather than physical existence.
Visual images are of two types; Real Images- those having a real physical existence such as a photographic image. Mental Images; Those generated as a mental picture within our own minds and which are accessible only to subjective study.
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