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A refractor is the name for a telescope that uses a lens as its main optical component.

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The earliest telescopes were refractors.

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They were made of glass lenses, and refractors were how telescopes were made until they became so big that it was impossible to support such a large weight of glass as the primary lens aperture of the telescope, at which point the design moved towards the reflecting telescope because it was easier to engineer.

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So, refractors are telescopes that use lenses and not mirrors.