Analysis of the effect of lens shutter on image motion in aerial camera

In order to improve the photographic resolution of aerial remote sensing cameras and obtain high-resolution aerial images, besides optical system with high modulation transfer function and high-quality imaging medium, the exposure time of shutter should be controlled correctly to ensure that the detector can obtain an appropriate image motion value. Based on the structure and working principle of the lens shutter of an aerial mapping camera, we establish the matrix relationship between the ground object and the image through coordinate transformation method, that is, the relationship between the exposure time of the shutter and the image motion value is determined. The image motion value and residual error of the image motion are analyzed by combining the parameters of the camera speed-height ratio and the pixel size. According to the different installation modes of the aerial camera, when the residual error of the image motion value is more than 1/3 of a pixel in size, the Image Motion Compensation (IMC) mechanism is necessary to the imaging system. Thus a theoretical basis for the design of the IMC mechanism in an aerial camera is provided. The analysis is validated by a static test and flight test. The test results show that the aerial camera clearly captures images and the spatial resolution of its images reaches 36.8 lp/mm, which meets the requirements of our technical index.