Reflective dual field-of-view optical system

A dual-state reflective optical relay system based on the Alvarez system is proposed, which can be used for remote sensing applications. By incorporating a double reflective freeform subsystem into a Three-Mirror Anastigmat telescope (TMA) with an intermediate image plane, two different object fields can be imaged within a single optical system. Using mechanically moved freeform mirror substrates, this subsystem enables a discrete change in focal length. Featuring a compact structure with only two moving parts, freeform optical mirrors and nearly diffraction limited performance at a wavelength of 8 µm, it represents an attractive space application subsystem.