Ukukhanya okusebenzayo kunokukhanya okukhanyayo kwe-1600-2000lm, kukhululekile ngakumbi ukusebenzisa ngamehlo kwaye akuchaphazeli umsebenzi.Uyilo oluphathekayo, lunokuthwalwa lula.Inokubekwa kumhlaba osicaba.Ihuku ityhilwe kwaye ixhonywe emoyeni ukuqinisekisa ukuba indawo osebenzela kuyo ikhanya kakuhle.