parabolic mirror

2 definitions found

parabolic mirror - Collaborative International Dictionary of English v.0.48 :

  Parabolic \Par`a*bol"ic\, Parabolical \Par`a*bol"ic*al\, a. [Gr.
     paraboliko`s figurative: cf. F. parabolique. See Parable.]
     [1913 Webster]
     1. Of the nature of a parable; expressed by a parable or
        figure; allegorical; as, parabolical instruction.
        [1913 Webster]
  
     2. [From Parabola.] (Geom.)
        (a) Having the form or nature of a parabola; pertaining
            to, or resembling, a parabola; as, a parabolic curve.
        (b) Having a form like that generated by the revolution of
            a parabola, or by a line that moves on a parabola as a
            directing curve; as, a parabolic conoid; a parabolic
            reflector; a parabolic antenna.
            [1913 Webster +PJC]
  
     Parabolic conoid, a paraboloid; a conoid whose directing
        curve is a parabola. See Conoid.
  
     Parabolic mirror (Opt.), a mirror having a paraboloidal
        surface which gives for parallel rays (as those from very
        distant objects) images free from aberration. It is used
        in reflecting telescopes.
  
     Parabolic spindle, the solid generated by revolving the
        portion of a parabola cut off by a line drawn at right
        angles to the axis of the curve, about that line as an
        axis.
  
     Parabolic spiral, a spiral curve conceived to be formed by
        the periphery of a semiparabola when its axis is wrapped
        about a circle; also, any other spiral curve having an
        analogy to the parabola.
        [1913 Webster]

parabolic mirror - WordNet (r) 2.1 (2005) :

  parabolic mirror
      n 1: a parabolic reflector for light radiation