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The maximum distance the particles of a medium move away from their rest positions as a wave passes through the medium.
The complete range of electromagnetic waves placed in order of increasing frequency.
The bouncing back of an object or wave when it hits a surface through which it cannot pass.
The point at which light rays parallel to the optical axis meet, or appear to meet, after being reflected (or refracted) by a mirror (or a lens).
A curved piece of glass or other transparent material that is used to refract light; the flexible structure that focuses light that has entered the eye.
The circular structure the surrounds the pupil, a ring of muscle tissue, that expands and contracts to change the size of the pupil opening
The layer of light sensitive sensory cells at the back of the eye on which an image is focused.
Receptor cells in the eye that work best in dim light and enable you to see black, white, and gray.
A type of vision that sees nearby things clearly, but objects at a distance are blurred.
An optical instrument that uses lenses to focus light, and film (or light sensitive optics) to record an image of an object
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