Iilensi zelanga eziqhelekileyo, zilingana nokungabikho kweqondo leeglasi ezigqityiweyo.I-lens efakwe umbala inokudityaniswa ngemibala eyahlukeneyo ngokomyalelo wabathengi kunye nokukhetha.Umzekelo, ilensi enye inokufakwa tint ngemibala emininzi, okanye ilensi enye inokuthatywa ngokutshintsha ngokuthe ngcembe imibala (idla ngokuba yimibala ethambekileyo okanye eqhubelekayo).Idityaniswe nesakhelo sezibuko zelanga okanye isakhelo se-optical, iilensi ezinemibala, ezaziwa ngokuba ziiglasi zelanga ezinedigri, azisombululi kuphela ingxaki yokunxiba iiglasi zelanga kubantu abaneempazamo zokukhanyela, kodwa zidlala indima yokuhombisa.
iithegi:I-1.56 index resin lens, i-1.56 lens yelanga