Catadioptric telescopes

Catadioptric Telescope Optical telescope that makes use of both reflective and refractive properties. 

Optical Telescopes. Optical telescopes are designed to gather and focus light that radiates from distant objects. The two main types of optical telescopes are reflectors and refractors. Each type is based on a different principle derived from the physics of light. A third type, a catadioptric telescope, is a hybrid of reflectors and refractors. 

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