Based on an automatic and fast variable field solar photometer (VFOVSP) developed, the fast measurement of solar radiation in different fields of view is realized, which provides a new technical means for distinguishing aerosol particles from cloud particles for ground measurement. The novel photometer adopts the sun tracking technology based on CCD image sensor and a programmable variable fields aperture, which can realize the rapid measurement of different fields of view in a short time interval. Through preliminary analysis of the measurement data of different fields of view under different weather conditions, it is shown that the way of comparing the changes in atmospheric optical thickness measured in different fields of view can provides a new technology of distinguishing thin cloud and aerosol. This method can quickly identify whether cirrus cloud exist in current atmospheric environment, which provides a foundation for studying the characteristics of cirrus cloud.