semantic pointers
hyponym
autofocus
biprism
camera lucida
coelostat
collimator
diffraction grating, grating
diffuser, diffusor
finder, viewfinder, view finder
Kerr cell
laser, optical maser
lens, lense, lens system
Nicol prism
planetarium
polarimeter, polariscope
prism, optical prism
projector
Rochon prism, Wollaston prism
stereoscope
viewer
hypernym