Cushman, Darby & Cushman
Retrofocus type super wide angle lens system
 Retro-focus type super wide angle lens system comprising a first positive meniscus lens component having the convex surface on the object side, a second negative meniscus lens component having the convex surface on the object side, a third negative meniscus lens component having the convex surface on the object side, a fourth positive lens component, a fifth negative meniscus lens component, a sixth positive cemented lens component, a seventh negative cemented lens component, an eighth positive meniscus lens component having the convex surface on the object side, a ninth positive lens component, and a filter disposed between the fifth and sixth lens components. In this lens system, aberrations are well corrected. 
Olympus Optical Co., Ltd.
G G
G02B G02B
inventional inventional
Kazuo Toru
Ikari Fujii