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  2. Parabolic reflector - Wikipedia

    en.wikipedia.org/wiki/Parabolic_reflector

    Parabolic reflectors are popular for use in creating optical illusions. These consist of two opposing parabolic mirrors, with an opening in the center of the top mirror. When an object is placed on the bottom mirror, the mirrors create a real image, which is a virtually identical copy of the original that appears in the opening. The quality of ...

  3. Reflecting telescope - Wikipedia

    en.wikipedia.org/wiki/Reflecting_telescope

    It has a parabolic primary mirror, and a hyperbolic secondary mirror that reflects the light back down through a hole in the primary. The folding and diverging effect of the secondary mirror creates a telescope with a long focal length while having a short tube length.

  4. Newtonian telescope - Wikipedia

    en.wikipedia.org/wiki/Newtonian_telescope

    Newtonian telescope design. A Newtonian telescope is composed of a primary mirror or objective, usually parabolic in shape, and a smaller flat secondary mirror.The primary mirror makes it possible to collect light from the pointed region of the sky, while the secondary mirror redirects the light out of the optical axis at a right angle so it can be viewed with an eyepiece.

  5. Parabola - Wikipedia

    en.wikipedia.org/wiki/Parabola

    A concave mirror that is a small segment of a sphere behaves approximately like a parabolic mirror, focusing parallel light to a point midway between the centre and the surface of the sphere. As the affine image of the unit parabola

  6. Coma (optics) - Wikipedia

    en.wikipedia.org/wiki/Coma_(optics)

    Coma is an inherent property of telescopes using parabolic mirrors. Unlike a spherical mirror, a bundle of parallel rays parallel to the optical axis will be perfectly focused to a point (the mirror is free of spherical aberration), no matter where they strike the mirror. However, this is only true if the rays are parallel to the axis of the ...

  7. Illusion transmitter - Wikipedia

    en.wikipedia.org/wiki/Illusion_transmitter

    An illusion transmitter uses two parabolic mirrors to transmit 3-D illusions of an object by use of a camera trained on the first mirror, which then sends video signals to a projector aimed at the second mirror.

  8. Paraboloid - Wikipedia

    en.wikipedia.org/wiki/Paraboloid

    For a proof, see Parabola § Proof of the reflective property. Therefore, the shape of a circular paraboloid is widely used in astronomy for parabolic reflectors and parabolic antennas. The surface of a rotating liquid is also a circular paraboloid. This is used in liquid-mirror telescopes and in making solid telescope mirrors (see rotating ...

  9. Telescope - Wikipedia

    en.wikipedia.org/wiki/Telescope

    The mirrors are usually a section of a rotated parabola and a hyperbola, or ellipse. In 1952, Hans Wolter outlined 3 ways a telescope could be built using only this kind of mirror. [36] [37] Examples of space observatories using this type of telescope are the Einstein Observatory, [38] ROSAT, [39] and the Chandra X-ray Observatory.