Steinheil Cemented
Achromatic Triplets

Barta xudunta ah ee fallaadhaha iftiinka ee dhex mara badhtamaha lensku way ka duwan yihiin barta ay fallaadha iftiinka ee ka gudbaya cidhifyada muraayadda, tan waxa loo yaqaannaa aberration spherical; marka falaadhaha ilayska ay maraan lens-ka convex-ka ah, barta xudunta u ah iftiinka cas ee leh mawjadda dheer ayaa ka fog barta isha ee iftiinka buluuga ah kaas oo leh hirar gaaban, taas oo keentay in midabada ay u muuqdaan inay dhiig baxayaan, tan waxaa loo yaqaannaa aberration chromatic. Maaddaama jihada uu ku dhaco aberration spherical lens convex ka soo horjeeda lens concave, iyada oo la isku daraa laba ama in ka badan lenses fallaadhaha iftiinka la samayn karaa si ay isugu ururaan hal dhibic, tan waxaa loo yaqaan aberration sixitaanka. Muraayadaha achromatic waxay ku saxan yihiin cilladaha chromatic iyo spherical labadaba. Halbeegyadayada achromat-ka caadiga ah waxaa loo qaabeeyey oo loo soo saaray si loo qanciyo dulqaadka ugu adag ee looga baahan yahay laser-ga wax qabad sarreeya ee maanta, elektro-optical iyo nidaamyada sawirka.