Double-beam-expanding cascade polarization testing system for large-aperture optical remote sensor

According to the double-beam-expanding cascaded polarization testing system for a large-aperture optical remote sensor; the incident plane angle of a polarization assembly is strictly controlled through a first-stage beam expanding system, high-precision polarization modulation is achieved, and the problem that traditional polarization testing is limited by the technological level of the polarization assembly is solved; and then large-aperture polarized light beam output is realized through a secondary off-axis reflection type beam expanding system, full-aperture and full-optical-path polarization testing is realized, and the polarization testing requirement of the large-aperture optical remote sensor is met. A double-beam-expanding cascade mode is adopted, polarization modulation errors are reduced, the extinction ratio of emergent beams is increased, and then the polarization test precision is improved; and the cascaded secondary beam expanding system can further realize full-aperture and full-optical-path