IMAGING OPTICAL SYSTEMS, AND IMAGING DEVICE PROVIDED WITH SAME

WIPO Patent Application WO/2016/113921

A1

These imaging optical systems include two imaging optical systems having different focal distances. Each of the imaging optical systems is provided with the same diaphragm member, and has, provided in order from the object side, a front-side lens group (GF) having positive refractive power, a focus lens group (Fo) having negative refractive power, and a rear-side lens group (GR) having positive refractive power. The diaphragm member is disposed in the vicinity of the focus lens group (Fo). Only the focus lens group (Fo) moves along the optical axis. Each of the imaging optical systems satisfies conditional expression (1), namely 0.5