An application of PECHAN prism in infrared search and track system

To solve real-time image de-rotation problems in infrared search and track (IRST) system design, the paper by adding a set of PECHAN Prism in infrared search and track system achieves image de-rotation. In order to get the image de-rotation prism corresponding with the actual engineering needs, it analyzes the main influential factor of prism and designs a 3~5μm MWIR image de-rotation prism. In order to ensure the performance of the optical system, it uses a new PECHAN Prism parallelism error detection method, which measured that the incident parallelism error is 1′16″. The parallelism error after alignment meets the system requirement. In this paper, the PECHAN Prism image de-rotation method significantly reduces the system’s optical path length to 170.5mm. This method will play an important role in miniaturization, light weight and engineering of product.