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equivalent focal length

noun

optics the ratio of the size of an image of a small distant object near the optical axis to the angular distance of the object in radians

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Nearby words

  1. equivalence relation,
  2. equivalency,
  3. equivalent,
  4. equivalent air speed,
  5. equivalent circuit,
  6. equivalent weight,
  7. equivalve,
  8. equivocal,
  9. equivocally,
  10. equivocate
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012