[W/K] :: Microscope

  Achromatic \Ach`ro*mat"ic\, a. [Gr. 'achrw`matos colorless; 'a
     priv. + chrw^ma, chrw`matos, color: cf. F. achromatique.]
     1. (Opt.) Free from color; transmitting light without
        decomposing it into its primary colors.
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     2. (Biol.) Uncolored; not absorbing color from a fluid; --
        said of tissue.
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     Achromatic lens (Opt.), a lens composed usually of two
        separate lenses, a convex and concave, of substances
        having different refractive and dispersive powers, as
        crown and flint glass, with the curvatures so adjusted
        that the chromatic aberration produced by the one is
        corrected by other, and light emerges from the compound
        lens undecomposed.
  
     Achromatic prism. See Prism.
  
     Achromatic telescope, or microscope, one in which the
        chromatic aberration is corrected, usually by means of a
        compound or achromatic object glass, and which gives
        images free from extraneous color.
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  Microscope \Mi"cro*scope\, n. [Micro- + -scope.]
     An optical instrument, consisting of a lens, or combination
     of lenses, for making an enlarged image of an object which is
     too minute to be viewed by the naked eye.
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     Compound microscope, an instrument consisting of a
        combination of lenses such that the image formed by the
        lens or set of lenses nearest the object (called the
        objective) is magnified by another lens called the ocular
        or eyepiece.
  
     Oxyhydrogen microscope, and Solar microscope. See under
        Oxyhydrogen, and Solar.
  
     Simple microscope, or Single microscope, a single convex
        lens used to magnify objects placed in its focus.
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  microscope
       n : magnifier of the image of small objects; "the invention of
           the microscope led to the discovery of the cell"