Assertion: telescope's mirror | /r/HasProperty | hyperbolic
Facets:
Source sentences:
text: The Ritchey–Chrétien telescope, invented by George Willis Ritchey and Henri Chrétien in the early 1910s, is a specialized Cassegrain reflector which has two hyperbolic mirrors (instead of a parabolic primary).
text: After that, telescopes used mostly the Ritchey–Chrétien design, using two hyperbolic mirrors to remove both spherical aberration and coma, leaving only astigmatism, giving a wider useful field of view.
text: The classic Cassegrain configuration uses a parabolic reflector as the primary while the secondary mirror is hyperbolic.