#lens_system__lens  a transparent optical device used to converge or diverge transmitted light and to form images
  supertype:  #optical_device__opticaldevice  a device for producing or controlling light
  part of:  #optical_instrument
  subtype:  #anastigmat  compound lens or lens system designed to be free of astigmatism and able to form approximately point images
  subtype:  #anastigmatic_lens  a lens designed to correct astigmatism
  subtype:  #camera_lens__optical_lens  a lens that focuses the image in a camera
     subtype:  #closeup_lens  a photographic lens with a short focal length used to take pictures at short ranges
     subtype:  #portrait_lens  a compound camera lens with a relatively high aperture
     subtype:  #telephoto_lens__zoom_lens  a camera lens that magnifies the image
     subtype:  #wide-angle_lens__fisheye_lens  a camera lens having a wider than normal angle of view (and usually a short focal length); produces an image that is foreshortened in the center and increasingly distorted in the periphery
  subtype:  #compound_lens  a lens system consisting of two or more lenses on the same axis
     subtype:  #achromatic_lens__achromaticlen  a compound lens system that forms an image free from chromatic aberration
  subtype:  #optical_condenser__opticalcondenser__condenser  lens used to concentrate light on an object
     subtype:  #Abbe_condenser  a condenser having 2 or 3 lenses with wide aperture for use in microscopes
  subtype:  #contact_lens  a thin curved glass or plastic lens designed to fit over the cornea in order to correct vision or to deliver medication
  subtype:  #converging_lens__convex_lens  lens such that a beam of light passing through it is brought to a point or focus
  subtype:  #crown_lens  a lens made of optical crown glass
  subtype:  #diverging_lens__concave_lens  a lens such that a parallel beam of light passing through it is caused to diverge or spread out
  subtype:  #eyepiece__ocular  combination of lenses at the viewing end of optical instruments
  subtype:  #Fresnel_lens  lens composed of a number of small lenses arranged to make a lightweight lens of large diameter and short focal length
  subtype:  #intraocular_lens  an artificial lens that is implanted into the eye of someone to replace a damaged natural lens or someone who has had a cataract removed
  subtype:  #monocle__eyeglass  lens for correcting defective vision in one eye; held in place by facial muscles
  subtype:  #object_glass__objective  the lens or system of lenses nearest the object being viewed

No statement uses or specializes #lens_system; click here to add one.