The invention discloses an 
exposure time adjusting method for 
earth observation frame transfer area array CCD 
image motion matching and relates to a frame transfer area array CCD 
exposure time adjusting method for solving the problem that when the 
exposure time is too short, the 
signal to 
noise ratio is too low, and when the exposure time exceeds one equivalent line period, obvious image blurringoccurs, so that the dynamic 
transfer function declines along the 
orbit direction in the existing 
earth observation imaging application. The method comprises the steps of (1) light-sensitive area useless charge frame transfer phase; (2) controllable-time 
image motion matching exposure phase; (3) light-sensitive area useful charge frame transfer and original 
storage area same-line useless charge dumping phase; (4) 
storage area residual useless charge and light-sensitive area transition-line charge dumping phase; and (5) 
storage area useful charge frame reading phase. According to the method, theinterval of two times of frame transfer in the light-sensitive area is changed to control the exposure time, a mechanical 
shutter is not needed, and the original hardware circuit is not modified; andin addition, the image blurring problem under long exposure time is effectively solved.