Long Wave Infrared Fast Objective with Wide Field of View
大视场大相对孔径长波红外物镜

A fast wide angle objective suitable for uncooled focal plane array(FPA) detectors is discussed. Its optical system composes of three aspheric germanium lenses that form imagery telecentric structure and have negative, positive, and positive power in sequence. Its full field of view and relative aperture are up to 135 degrees and F/0.8, respectively. Its imaging performance approaches diffraction limit. And it has advantages of compactness, lightweight, and uniform illumination in the field. The manufacture and the test of the objective are described. Also, the measured modulation transfer function (MTF) and the thermal image taken with the objective are given in this paper.