The principles of ergonomics design in fundus cameras should be extending the agreeableness by
automatic control. Firstly, a 3D positional numerical control system is designed for positioning the
eye pupils of the patients who are doing fundus examinations. This system consists of a
electronically controlled chin bracket for moving up and down, a lateral movement of binocular
with the detector and the automatic refocusing of the edges of the eye pupils. Secondly, an
auto-focusing device for the object plane of patient’s fundus is designed, which collects the
patient’s fundus images automatically whether their eyes is ametropic or not. Finally, a moving
visual target is developed for expanding the fields of the fundus images.