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{%type%} Definitions

WordNet 3.0Copyright Princeton University
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Short "hint"

A compound lens made by combining lenses of different glasses (as flint glass and crown glass) with different focal powers so that the light emerging from the lens forms an image almost free from unwanted colors

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Usage examples (7)
  • PS: Vision in a complete achromat: a personal account is a very interesting feature on achromatopsia by vision scientist Knut Nordby.
  • The magician's tale / David Hunt —An achromat suffering from total color blindness, Kay possesses a vision that informs her world and sharpens her skills as talented...
  • You can, for example, buy semi-plan apochromatic objectives and plan achromat objectives.
  • An achromat brings those two wavelengths to the same focus, with other wavelengths very slightly out of focus.
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