The effect of the change of atmospheric pressure

temperature and oblique photographic distance on being out of focus of aerial camera during aerial photograph is analyzed.The simple maths equation is presented in order to calculate out of focus.The configuration and design principle of autofocusing system for data acquisition and processing based on high precision silicon pressure sensor

platinum resistance temperature sensor and GPS for aerial camera are introduced.The hardware circuit and the software process design are done.The optical measurement and practical application show that the design is practical and reliable.It has high speed and high precision focusing.