principal axis

Definitions

Electronics

  • A line passing through both centers of curvature of a lens. light travels along this axis with no deviation. Also called optical axis (1).
  • A line passing through the centers of curvature of a lens or other optical system. Light travels along this axis with no deviation. Also called optical axis (2).
  • The axis along which light is transmitted through a doubly-refracting crystal or medium without double refraction. Also called optical axis (3).
  • A reference axis chosen in a manner which provides for maximum symmetry, greatest response, or the like.
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