spectacles

(spek’tak-lz) [L. spectacw/la; specta’re to sec]. A pair of lenses in a frame to a ist vision. bifocal s., Franklin s., pantoscopic 8., spectacles with two half-lenses of different foci for each of the eyes: the upper half for distant, and the lower for near, vision. compound 8., spectacles fitted with extra colored gla es, or extra lenses, to be used as occasion requires. decentered 8., spectacles with lenses formed from eccentric portions of two convex lenses. divided s., bifocal spectacles. Ma elon’s s., spectacles with an attachment for keeping the upper lid raised in cases of paralytic ptosis. mica- 8., spectacles of sheet mica: used to protect the eye from foreign bodies. periscopic 8., spectacles with either menisci or concavoconvex surfaces toward the eyes: these allow the eyes considerable latitude of motion. prismatic 8., spectacles for correcting muscular defects. pulpit s., spectacles containing the lower segments of the lenses only. stenopeic s8., spectacles fitted with metal plates, having each a small central aperture. tinted s8., spectacles of a gla so colored as to protect the eyes from the effects of too bright light. wire-frame s., a kind of spectacles of wire gauze worn to protect the eye from the entrance of foreign bodies.