Correlation model of space camera

For many years, the film series aerial photogrammetry cameras used in China's aerial photography production are mainly imported from abroad. The main product types are model airplane camera, RMK model airplane camera and A φ A mapping model airplane camera. It is characterized by meeting the accuracy requirements, strict meteorological guarantee conditions and long surveying and mapping collection period.

At the ISPRS Amsterdam conference in 2000, aerial digital cameras began to appear; By the ISPRS Istanbul Conference in 2004, aerial digital cameras have become a hot area of concern. The representative three-line array camera in aerial digital camera is Leica ADS40. It arranges three CCD linear arrays of forward view, down view and back view on the imaging plane to form three navigation bands, so as to realize photogrammetry during photography. Due to technical reasons, it is still difficult to produce a large array CCD camera with an image width of 23 cm ×23 cm. Foreign countries are vigorously developing splicing technology, splicing medium-sized CCD into large-size area array CCD to meet the application. In recent years, a large area CCD aerial camera has been developed by combining software and hardware internationally. Representative cameras include DMC jointly developed by Germany and the United States and UltraCamD, a large-scale area camera system introduced by Austrian company Vexcel. The DMC panchromatic band consists of four CCD cameras with a resolution of 4K×4K and a pixel size of12um. . UltraCamD consists of 8 lenses, of which 4 lenses are linearly arranged along the route direction, which is a full-color channel; The four lenses are distributed in four corners and are multi-spectral channels.

China attaches great importance to the research and development of aerial digital cameras, and has made great breakthroughs, and developed some products with international advanced level, which are even better than similar products abroad in some aspects.

Developing large-area aerial digital cameras is an important direction in the future. It has many advantages. First, it has strong adaptability to the environment. Digital camera has high sensitivity and strong adaptability of light source, which can realize aerial photography under different meteorological conditions and even clouds, reducing the requirements of meteorological conditions for photography and greatly shortening the photography cycle. Second, efficient and real-time. To digitize the image taken by a film camera, it must go through three steps: photographing, developing and scanning, and the acquisition period is relatively long. While taking photos with digital camera does not need film, darkroom and scanner, the captured images can be transmitted in real time and directly input into the computer for processing, which greatly improves the work efficiency. Third, the application of surveying and mapping is simple and fast. Area array camera is compatible with the current surveying and mapping production system in data application and processing, and the existing equipment can fully meet the requirements of area array camera data processing. Fourth, the cost performance is high. Using digital area camera can save 50% to 75% of the cost compared with using film camera, and the radiation accuracy and geometric accuracy of the obtained digital image will be greatly improved.