optical instrument(n = noun.artifact) - an instrument designed to aid vision;
is a kind of instrument
has parts: lens, lens system, lense
has particulars: binoculars, field glasses, opera glasses, esophagoscope, oesophagoscope, jeweler's glass, periscope, projector, sights, eyeglasses, glasses, specs, spectacles, prism spectroscope, spectroscope

beating-reed instrument, bowed stringed instrument, brass instrument, commercial instrument, debt instrument, derivative instrument, double-reed instrument, drafting instrument, electronic instrument, execution of instrument, free-reed instrument, instrument, instrument flying, instrument landing, instrument of execution, instrument of punishment, instrument of torture, instrument panel, legal instrument, measuring instrument, medical instrument, musical instrument, musical instrument digital interface, navigational instrument, negotiable instrument, optical, optical aberration, optical activity, optical bench, optical cable, optical condenser, optical crown, optical crown glass, optical device, optical disc, optical disk, optical fiber, optical fibre, optical flint, optical fusion, optical glass, optical illusion, optical lens, optical maser, optical opacity, optical phenomenon, optical prism, optical pyrometer, optical telescope, percussion instrument, percussive instrument, recording instrument, reed instrument, scientific instrument, sealed instrument, single-reed instrument, stringed instrument, surgical instrument, surveying instrument, surveyor's instrument, test instrument vehicle, time-delay measuring instrument, transit instrument, wind instrument, woodwind instrument