The the Chart purojekiti ndeyekubatsira-pur-yakadzvanywa mudziyo wakagadzirirwa chirongwa chemufananidzo pachiratidziri chekuongororwa kwekuona. Chati yakatakura disc, iyo mask ndiro uye iyo ashmmatic index tube inogona kudzorwa nemapanga ese akapihwa pane yepamberi pane purojekiti.