title: Design of all-reflective dual-channel foveated imaging systems based on freeform optics.
abstract: This paper presents a practical method to design all-reflective dual-channel foveated imaging systems. Such a system statically has two optical channels, one with a wider field-of-view for searching and another with a long focal length for fine reconnaissance. The two channels have a common center field angle. These systems may be useful for remote sensing where coarse searching and fine observation are simultaneously needed. To demonstrate the method, two corresponding systems are designed. The results reveal an angular resolution of finer than 4 arcsec for fine observation and a zoom ratio of 2.9× or 2.5× between the two channels. The modulation transfer function curves of both channels are above 0.3 at 100 line pairs per millimeter (lp/mm). Freeform surfaces are adopted to improve imaging quality and obtain a proper structure for fabrication.
authors.forename: Chen
authors.initials: C
authors.lastname: Xu
authors.forename: Dewen
authors.initials: D
authors.lastname: Cheng
authors.forename: Jinjin
authors.initials: J
authors.lastname: Chen
authors.forename: Yongtian
authors.initials: Y
authors.lastname: Wang