Using the liquid crystal spatial light modulator as the wavefront compensator, an open-loop adaptive optics system for retinal imaging is developed. Compared with the closed-loop liquid crystal adaptive optics system, the energy efficiency is doubled. The fundus is illuminated twice by two laser pulses throughout a single correction loop, which will be much safer for the human eye. A modified mechanical shutter is incorporated in the illumination channel to change the imaging field, and the field of view is thus increased from 0.8° to 1.7°. The timing sequence is optimized, and the continuous correction is performed. Meanwhile, the imaging camera is adjusted to achieve the best image plane. The residual wavefront error after open-loop correction is approximately equal to 0.09λ, and the Strehl ratio is bigger than 0.70. It is a nearly diffraction limited system. The clear photoreceptor images are obtained through open-loop correction.