dioptric

Etymology
From Greek διοπτρικός. Compare diopter.

Adjective

 * 1) Acting as a medium for sight; making use of refraction (of lenses, etc.).
 * 2)  Pertaining to a diopter.
 * 3)  Capable of being seen through.
 * 1)  Capable of being seen through.

Noun

 * 1)  The branch of optics concerned with refraction.
 * 2) A dioptric telescope.

Etymology
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