Optical design of common-aperture multispectral and polarization optical imaging system with wide field of view

Multispectral and polarization cameras that can simultaneously acquire the spatial, spectral, and polarization characteristics of an object have considerable potential applications in target detection, biomedical imaging, and remote sensing. In this work, we develop a common-aperture optical system that can capture multispectral and polarization information. An off-axis three-mirror optical system is mounted on the front end of the proposed system and used as a common-aperture telescope in the visible light (400 nm-750 nm) and long-wave infrared (LWIR, 8 μm-12 μm) waveband. The system can maintain a wide field of view (4.5°) and it can demonstrate an enhanced identification ability. The off-axis three-mirror system gets rid of central obscuration while further yielding stable system resolution and energy. Light that has passed through the front-end common-aperture reflection system is divided into the visible light and LWIR waveband by a beamsplitter. The two wavebands then converge on two detectors through two groups of lenses. Our simulation results indicate that the proposed system can obtain clear images in each waveband to meet the diverse imaging requirements.