Analysis and Design of the Medium Wave Infrared Polarization Co-Aperture Optical System

This paper analyzes the development status of the infrared polarization imaging system. According to the application need of medium wave infrared (MWIR) polarization image, this paper proposes a MWIR polarization co-aperture optical system. The system is composed of the front co-aperture optical system and the rear sub-aperture optical system. The rear separate aperture optical system includes four polarization channels. Each channel adopts a 1/4 wave plate and a linear polarizers to obtain three line Stokes polarization components and one circularly Stokes polarization components Thus the system could achieve full polarization imaging. According to the detector and the corresponding application needs, the calculation and optical system design were completed. After the design, the MTF of the optical system is more than 0.3@171p/mm. The maximum RMS spot diameter is less than the size of detector pixel and a single pixel energy concentration is greater than 80%.